Patent ID: 12222683

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments will be described in detail with reference to the drawings. Note that the present invention is not limited to the following description. It will be readily appreciated by those skilled in the art that modes and details of the present invention can be modified in various ways without departing from the spirit and scope of the present invention. Thus, the present invention should not be construed as being limited to the description in the following embodiments.

Note that in structures of the present invention described below, the same portions or portions having similar functions are denoted by the same reference numerals in different drawings, and a description thereof is not repeated. Furthermore, the same hatching pattern is applied to portions having similar functions, and the portions are not especially denoted by reference numerals in some cases.

Note that in each drawing described in this specification, the size, the layer thickness, or the region of each component is exaggerated for clarity in some cases. Therefore, the size, the layer thickness, or the region is not limited to the illustrated scale.

Note that in this specification and the like, ordinal numbers such as “first,” “second,” and the like are used in order to avoid confusion among components and do not limit the number.

Embodiment 1

One embodiment of the present invention is a connecting member including a pipe, a spring, and a pair of pivots. The connecting member, in a watch-type device for example, can be used as a spring bar for attaching a band (also referred to as a strap, a belt, or the like) to a housing (also referred to as a body, a case, or the like). Note that, hereinafter, the connecting member of one embodiment of the present invention is referred to as a spring bar in some cases.

The pivots of the connecting member of one embodiment of the present invention each include a tip portion, a collar portion, an axis portion, and an end portion. The pair of pivots are electrically insulated from each other. The tip portion and axis portion of the pivot are electrically connected to each other and the surfaces thereof have conductivity.

The axis portion of the pivot can be electrically connected to one of a pair of electrodes (tabs, wirings, or the like) of a battery. The pair of pivots included in the connecting member are insulated from each other in this structure; therefore, the pair of electrodes of the battery can be prevented from being electrically connected to each other. Accordingly, the two tip portions positioned at the both ends of the connecting member are each electrically connected to either of the pair of electrodes of the battery. That is, the two tip portions can function as a pair of terminals of the battery.

The connecting member to which the battery is connected in such a manner is attached to an electronic device, which enables the battery to be used as an auxiliary power supply of the electronic device. Specifically, the electronic device is provided with a pair of bearings to which the connecting member can be attached, and power from the battery is supplied to the electronic device via the bearings and the connecting member.

When a secondary battery is used as the battery, the battery can be charged via the bearings of the electronic device and the connecting member. The electronic device itself may have a battery serving as a main power supply. In that case, it is preferable to set in advance or to be selectable by the user which battery is preferentially charged, the battery attached to the electronic device via the connecting member or the battery included in the electronic device itself.

A battery that includes a flexible film for its exterior body and that can be bent and straightened repeatedly can be favorably used as the battery. This allows the battery and part of the connecting member to be placed in the band-like exterior body. Therefore, the band-like exterior body can have an external appearance or fittability similar to those of conventional bands (straps, belts, or the like) that do not include batteries.

Note that in the case where a non-bendable battery is used as the battery, the battery can be placed in a portion which is not bent in the band-like exterior body. As the battery here, any of various batteries such as coin-type (or button-type) batteries, cylindrical batteries, or prismatic batteries can be used.

Such a band-like power supply device can be attached to the electronic device using the above connecting member, and thus can be easily replaced by the user. For example, the battery can be easily replaced in the cases where the charging amount of the battery is reduced, the battery deteriorates, and a primary battery is used as the battery. In the case where the auxiliary power supply is not required, the user can replace the power supply device with a conventional band (without a battery) using a conventional spring bar. The user has a free choice between the band-like power supply device and the conventional band according to the usage or his/her preference and can attach either of them to the electronic device.

The electronic device to which the connecting member or power supply device of one embodiment of the present invention is attachable preferably has a function of sensing a potential difference between the pair of bearings or a function of sensing a conductive or insulated state between the pair of bearings.

For example, when the connecting member of one embodiment of the present invention, a conventional spring bar, or the like is not attached to the electronic device, the pair of bearings are insulated from each other and each of the bearings is in an electrically floating state. In addition, in the case where the connecting member of one embodiment of the present invention to which the battery is not connected is attached to the electronic device, the pair of bearings are electrically insulated from each other. In the case where the conventional spring bar is attached to the electronic device, the pair of bearings are in an insulated or conductive (shorted) state depending on the materials of the spring bar. When a state in which the pair of bearings are electrically connected to or insulated from each other is sensed as described above, it can be determined that the connecting member to which the battery is connected is not attached to the electronic device, so that the electronic device can operate using power of another battery included in the electronic device itself.

In contrast, in the case where the connecting member of one embodiment of the present invention to which the battery is connected is attached to the electronic device, a potential difference corresponding to an output voltage of the battery is generated between the pair of bearings. Sensing this potential difference makes it possible to determine the attachment of the connecting member to which the battery is connected, and the electronic device can operate using power supplied from the battery.

Specific structure examples of the connecting member, power supply device, and electronic device of one embodiment of the present invention and examples of a system of one embodiment of the present invention will be described below with reference to drawings.

Application Example

First, an example of an electronic device to which a connecting member and power supply device that will be described below are attached will be described. As an example of the electronic device, a watch-type information terminal device is described here.

FIGS.1A and1Bshow an example of an electronic device30to which connecting members10, a power supply device20a, and a power supply device20bare connected.FIG.1Ais a front view andFIG.1Bis a side view.

The electronic device30includes a housing31and a switch35. The switch35is provided on a side surface of the housing31. The housing31includes a display portion32, lugs33, and bearings34.

A variety of image information can be displayed on the display portion32. A display device in which a display element such as a liquid crystal element or an organic EL element is used can be used for the display portion32. In addition, a touch panel functioning as a touch sensor is preferably used for the display portion32.

Note that in order to use the electronic device30as an analog watch, not as an information terminal device, the display portion32can be replaced with a watch dial including at least one of an hour hand, a minute hand, and a second hand. In order to use the electronic device30as a digital watch, the display portion32can be replaced with a watch dial including a segment type liquid crystal element or the like.

The switch35serves as one of user interfaces. The user can make operations for the switch35such as pushing, pulling, winding, or sliding up and down or back and forth, for example. The electronic device30can start or switch applications or execute other processings in response to these operations. Note that although an example in which the housing31includes one switch35is described here, the housing31may include another switch or the like.

The lug33provided on the housing31is a portion to which a spring bar or the like, in addition to the connecting member10, is attached. Alternatively, part of the housing31may serve as the lug33. There are a pair of the lugs33provided symmetrically in the housing31. The pair of lugs33face each other. Each of the lugs33includes the bearing34on its inward-facing surface. Therefore, the connecting member10can be attached to the pair of bearings34facing each other.

Each of the bearings34includes a depressed portion into which a later-described tip portion12aof a pivot12included in the connecting member10is inserted. The bearing34includes a conductive portion to which a potential of the tip portion12ais applied.

The power supply device20aand the power supply device20beach serve as a wearing tool (a band, a strap, a belt, or the like) used when the electronic device30is worn on an arm or the like.

The power supply device20aand the power supply device20beach include a band-like exterior body21. A battery22is provided inside the exterior body21. The connecting member10is provided so as to be partly projected from the exterior body21. The battery22includes a pair of tabs23, each of which is joined with a conductive member25. The conductive member25fits a later-described axis portion12cof the pivot12included in the connecting member10, so that the conductive member25and the pivot12are electrically connected to each other.

Each of the pair of tabs23of the battery22is electrically connected to the bearing34via the connecting member10. This makes it possible to supply power to the electronic device30from the battery22and to charge the battery22by the electronic device30.

Note that although an example in which two power supply devices, the power supply device20aand the power supply device20b, are attached to the electronic device30is described here, either may be replaced with a normal wearing tool (band, belt, strap, or the like).

Structure Example of Connecting Member

FIG.1Cis a schematic cross-sectional view in a direction parallel to an axis direction of the connecting member10.

The connecting member10includes a pipe11, a pair of the pivots12, and a spring13.

The pivot12includes the tip portion12a, a collar portion12b, the axis portion12c, and an end portion12din this order from the outer side.

The pipe11is hollow and its ends are narrowed. Inside the pipe11, the spring13and the end portions12dof the pair of pivots12are provided. The spring13is provided so as to be shorter than its natural length in a natural state. Owing to the restoring force of the spring13, an outward force is applied to the pair of pivots12.

The tip portion12aand the collar portion12bare portions that are projected from the pipe11in a natural state. The axis portion12cincludes a portion that is projected from the pipe11in a natural state. The axis portion12calso includes a portion in which part of the axis portion12cis inserted in the pipe11when an external force is applied in a direction in which the spring13is compressed. The end portion12dis a portion that is placed in the pipe11in a natural state. A natural state here is a state where no external force is applied in the axis direction (a longitudinal direction) of the connecting member10.

A diameter of the end portion12dis greater than a diameter of a hole of the end of the pipe11. A diameter of the axis portion12cis the same as or smaller than the diameter of the hole of the end of the pipe11. This can prevent the pivot12from coming out from the pipe11even if a force is applied to the pivot12from the spring13.

The tip portion12ais a portion that is inserted into a hole of the bearing34of the electronic device30. The collar portion12bis a portion that is engaged with a depressed portion of the bearing34. When the connecting member10is attached to the electronic device30by not only inserting the tip portion12ainto the bearing34but also engaging the collar portion12bwith part of the bearing34, a more stable attachment can be achieved.

The collar portion12bcan also be used as a portion that is engaged with a detachment jig that can be used for attaching and detaching the connecting member10. This makes it easy that the connecting member10is attached to or detached from the electronic device30. The collar portion12bhas one or more portions whose diameters are greater than those of the tip portion12aand the axis portion12c. As illustrated inFIG.1C, the collar portion12bpreferably has two or more portions whose diameters are greater than those of the other portions because the convenience is improved. For example, a detachment jig can be positioned between the two portions having greater diameters.

FIG.1Cillustrates the conductive member25which is attached to the connecting member10. The conductive member25includes a portion into which the axis portion12cfits. The conductive member25can be attached to the axis portion12cin such a manner that the axis portion12cfits into the conductive member25. Here, the conductive member25is preferably attached to the axis portion12cso as to be slidable in an axis direction.

FIG.1Dis a schematic cross-sectional view of a state which is changed from the state ofFIG.1Cand in which the spring13is compressed by an external force applied to the pair of pivots12. As illustrated inFIG.1D, an external force is applied and then the spring13is compressed, so that part of the axis portion12cis inserted in the pipe11.

FIG.1Dillustrates a state in which the width of the conductive member25in the axis direction is equal to the width, in the axis direction, of the portion of the axis portion12cwhich is projected from the pipe11. One end of the conductive member25is in contact with the end of the pipe11and the other end of the conductive member25is in contact with the collar portion12b. That is, it can also be said that the pivot12cannot slide inside anymore and the connecting member10is most compressed inFIG.1D.

When an external force is relaxed, the state illustrated inFIG.1Dbecomes the state illustrated inFIG.1Cagain. At this time, the conductive member25attached to the axis portion12cis slidable; therefore, the position of the conductive member25remains as it is inFIG.1C.

Here, the tip portion12a, the collar portion12b, and part of the axis portion12chave conductive surfaces inFIGS.1C and1D. In contrast, the other part of the axis portion12cand the end portion12dhave insulating surfaces. Different hatching patterns are used for the conductive surfaces and the insulating surfaces inFIGS.1C and1D.

Even when the spring13is conductive, the pair of pivots12can be electrically insulated from each other owing to the insulating surface of the end portion12d.

Even when the pipe11is conductive, the pair of the pivots12can be electrically insulated from each other owing to the insulating properties of the end portion12dand part of the axis portion12c. When the pivots12are innermostly positioned as illustrated inFIG.1D, a portion of the axis portion12cwhich are in contact with the end of the pipe11preferably has an insulating property. In addition, it is important that the conductive portion of the axis portion12cis in contact with the conductive member25when the pivot12is outermostly positioned as illustrated inFIG.1C.

In the case where a surface of the end of the pipe11and a surface of the end of the conductive member25are each conductive, the pair of conductive members25are electrically shorted in some cases when the conductive members25and the pipe11are in contact with each other as illustrated inFIG.1C. To prevent this, an insulating cushioning material14is preferably provided between the conductive member25and the pipe11as illustrated inFIG.1E. As the cushioning material14, a ring-shaped component of rubber, plastic, or the like can be used.

For the pipe11, the pivot12, and the spring13, metals typified by stainless can be used here. When such a metal is used, in order to make their surfaces to be insulated partly or entirely, a method for oxidizing the surfaces, a method for forming an insulating coating film by a plating method or the like, or a method for coating the surfaces with an insulating resin or the like can be used, for example. Insulating materials such as a resin can also be used for the pipe11, the pivot12, and the spring13. When a resin is used, conductivity may be added to part or a whole of the surfaces. For example, a method for forming a conductive coating film by a plating method can be used.

Here, the structure of the connecting member10is not limited to the structures illustrated inFIG.1Cand other drawings, and any structure is acceptable as long as the structure includes the pair of pivots12that are electrically insulated from each other. Another example of the connecting member10will be described below.

In each of the pivots12included in the connecting member10inFIG.2A, a surface of the axis portion12cand a surface of the end portion12dare each conductive. At least an inner surface of the pipe11and surfaces of the openings of the pipe11have insulating properties. The pipe11contains two springs (a spring13aand a spring13b) and a cushioning material15therebetween. The cushioning material15has an insulating surface.

InFIG.2A, the spring13aand the spring13bare separated from each other by the cushioning material15. The spring13aand the spring13bare each in contact with the pipe11, and the contact surfaces have insulating properties. Therefore, the spring13aand the spring13bare electrically insulated from each other. Even in the case where the pair of pivots12are each conductive, the above structure prevents electrical shorting via the spring13aand the spring13b, and the pair of pivots12are electrically insulated from each other.

In addition, this structure enables the whole surfaces of the axis portions12cof the pivots12to be made conductive. This makes it possible to increase areas where the axis portions12care in contact with the conductive members25and to reduce the contact resistances therebetween.

FIG.2Billustrates an example in which the pipe11does not contain the cushioning material15as illustrated inFIG.2A, but includes a partition wall11a. The partition wall11ais positioned almost at the center of the pipe11and has a function of separating the spring13aand the spring13bfrom each other.

FIG.2Cillustrates an example in which a surface of the pipe11and a surface of the spring13each have an insulating property.

In the above structure, the conductive member25and the pivot12are electrically connected to each other because the conductive member25is in contact with the axis portion12cof the pivot12. However, the structure is not limited thereto, and any structure is acceptable as long as the conductive member25and the tip portion12aof the pivot12are electrically connected to each other.

FIG.2Dillustrates an example in which the pipe11includes a pair of conductive portions11band an insulating portion11cpositioned between the portions11b. The pair of portions11bare electrically insulated from each other. The portions11bfit into the conductive members25. Therefore, the pivots12and the conductive members25are electrically connected to each other via the portions11b.

It is preferable that the portions11band the portion11chave screw structures by which they are fastened, as illustrated inFIG.2D. Note that the portions11band the portion11cmay be joined to each other with an adhesive or the like.

FIG.2Dillustrates an example in which the spring13aand the spring13bare separated from each other by the cushioning material15; however, the spring13aand the spring13bmay be separated from each other by the partition wall11aof the pipe11like the structure illustrated inFIG.2B. In addition, a structure which does not include the cushioning material15but includes the spring13having an insulating surface as illustrated inFIG.2Emay be used.

The above is the description of the connecting member.

Structure Example of Battery

Structure examples of the battery22that can be used for a power supply device20will be described below.

FIG.3Ais a schematic top view of the battery22to which the conductive members25are connected. The battery22includes the pair of tabs23, an exterior body26, and a content27. The battery22is preferably a secondary battery.

A flexible and highly moisture-resistant film can be used for the exterior body26. For example, a stacked film of a metal film and a plastic film is preferably used. This makes it possible to achieve the bendable battery22.

The content27is sealed by the exterior body26. The exterior body26is thermocompression-bonded and joined outside the content27. The content27contains at least a positive electrode, a negative electrode, and an electrolyte. The details will be described later.

Each of the pair of tabs23is electrically connected to either the positive electrode or the negative electrode. The tabs23are partly projected from the exterior body26and not covered.

Each of the pair of tabs23is joined to the conductive member25by a joining method such as an ultra welding method.

The battery22may include a protective circuit.FIG.3Billustrates an example in which a substrate29including a protective circuit28is provided.

For example, a printed circuit board (PCB) or a flexible printed circuit (FPC) can be used as the substrate29. In the example illustrated inFIG.3B, the protective circuit28is an IC chip mounted on the substrate29.

As the protective circuit28, a circuit having a function of stopping charging in the case where the battery22is over charged, a function of stopping discharging in the case where the battery22is over discharged, or the like can be used, for example. In addition, the protective circuit28preferably has a function of preventing a high current flow in the case where the positive electrode and the negative electrode are electrically shorted.

The substrate29includes a pair of electrodes that are connected to the tabs23. The substrate29also includes a pair of electrodes that are connected to wirings24. The tabs23and the wirings24are joined to their respective electrodes of the substrate29by a joining method such as an ultra welding method.

The wirings24electrically connect the conductive members25to the substrate29. As the wirings24, cable wirings or FPCs may be used.

Note that a method for connecting via a connector may be used in order to connect the tabs23and the substrate29, the wirings24and the substrate29, and the wirings24and the conductive members25.

Note that althoughFIGS.3A and3Billustrate structure examples of the battery22in which a film is used as the exterior body26, the structure is not limited thereto and a coin-type (button-type) battery may be used.

FIG.3Cillustrates an example in which a coin-type battery41is used.FIG.3Dillustrates an example in which the substrate29including the protective circuit28is connected to the battery41.

Portions of an exterior body of the battery41(on its top side and rear side) serve as a positive electrode and a negative electrode. As illustrated inFIG.3C, an electrode42ais electrically connected to an electrode on the rear side of the battery41, and an electrode42bis electrically connected to an electrode on the top side of the battery41. Each of the electrode42aand the electrode42bis electrically connected to the conductive member25.

In order to use the coin-type battery41for the power supply device20which is attached to the watch-type electronic device30illustrated inFIG.1Aand other drawings, the battery41is preferably positioned at a portion which is not bent when the exterior body21of the power supply device20is worn on a wrist or the like. For example, it is preferable to position the battery41in the power supply device20near to or far from the electronic device30and not to position the battery41near the center.

The above is the description of the battery.

[Conductive Member]

Examples of the conductive member25that electrically connects an electrode (tab) of a battery and the connecting member10will be described below.

FIG.4Ais a schematic perspective view illustrating the conductive member25and part of the axis portion12cof the pivot12. Note that although the conductive member25is connected to the axis portion12chere as an example, the conductive member25may be connected to part of the pipe11as illustrated inFIG.2Dand other drawings by increasing the diameter of the conductive member25.

The conductive member25illustrated inFIG.4Aincludes a tubular portion including a hole which fits the axis portion12cand a leg portion which is joined to the tab of the battery or the like. In the example ofFIG.4A, a cross section of the tubular portion of the conductive member25is a ring shape and a cross section of the axis portion12cis a circle. Therefore, the conductive member25and the axis portion12ccan have a structure in which the conductive member25is rotatable around the axis portion12cin rotating directions indicated by the arrows inFIG.4A, and slidable in an extending direction of the axis portion12c.

FIG.4Billustrates an example in which the cross section of the axis portion12chas a partly cut-out shape. The shape of the hole of the conductive member25is similar to the shape of the cross section of the axis portion12cin order to fit the axis portion12c. Such a structure enables the conductive member25and the axis portion12cto be connected in a state where they are fixed in the rotating directions and slidable in the extending direction of the axis portion12c.

As illustrated inFIG.4C, the cross section of the axis portion12cmay be a substantially polygonal shape.FIG.4Cillustrates an example in which the cross section of the axis portion12cis a square shape having round corners. Such a structure also enables the conductive member25and the axis portion12cto be connected in a state where they are fixed in the rotating directions and slidable in the extending direction of the axis portion12c.

It is preferable that part of the conductive member25have a tubular shape as illustrated inFIGS.4A,4B, and4Cbecause an area where the conductive member25is in contact with the axis portion12ccan be increased. The tubular-shaped conductive member25may be formed in such a manner that a material that is compressed by heat or the like is used as the conductive member25, the conductive member25having a diameter larger than that of the collar portion12bis inserted from the tip portion12aside, and then, its diameter is compressed by heat or the like. Alternatively, a tubular-shaped portion of the conductive member25may be formed in such a manner that a band-like member is wounded around the axis portion12c.

FIG.4Dillustrates an example in which the conductive member25has a tubular shape which is partly cut out (also referred to as a shape having a circularly arced cross section). InFIG.4D, part on the side opposite to the leg portion is cut out. Such a structure makes it easy to attach and detach the axis portion12cto and from the conductive member25.

InFIG.4D, the conductive member25is connected to the axis portion12cso as to be rotatable around the axis portion12cin the rotating directions and slidable in the extending direction of the axis portion12c.

FIG.4Eillustrates an example in which the position of a cut-out portion of the conductive member25is different from that of the cut-out portion of the conductive member25inFIG.4D.

FIGS.4F and4Geach illustrate an example in which the cross section of the axis portion12cis not a round shape. Such a structure enables the conductive member25and the axis portion12cto be connected in a state where they are fixed in the rotating directions and slidable in the extending direction of the axis portion12c. In addition, the conductive member25and the axis portion12ccan be easily attached to and detached from each other.

The above is the description of the conductive member.

Structure Example of Power Supply Device

An example of a power supply device that can be attached to an electronic device will be described below. In particular, a power supply device that can be used for the watch-type electronic device30will be described here.

FIG.5Ais a schematic perspective view of the power supply device20aandFIG.5Bis a schematic perspective view illustrating the inside structure of the power supply device20a.

The power supply device20aincludes the connecting member10, the battery22, an exterior body21a, an exterior body21b, a buckle51, and the like. The connecting member10is partly projected from the power supply device20a.

As illustrated inFIG.5B, the battery22is positioned between the exterior body21aand the exterior body21b. Depressed portions for a space in which the battery22is provided are formed on the inner sides of the exterior body21aand the exterior body21b. This structure makes it possible to equal the thicknesses of a portion which includes the battery22and a portion which does not include the battery22, and to improve its fittability.

For the exterior body21aand the exterior body21b, a material used for a normal band (without a battery) or the like can be used. For example, any of various materials such as rubber, leather, cloth, a metal, and a resin can be used. Rubber or a resin is particularly preferable because it is easy to shape.

FIGS.6A and6Bare schematic perspective views of the power supply device20b, which is a counterpart to the power supply device20a. The power supply device20bincludes the connecting member10, the battery22, an exterior body21c, an exterior body21d, and the like.

The exterior bodies21cand21dare different from the exterior bodies21aand21bin that a plurality of holes52are provided instead of the buckle51.

In such a manner, the power supply device20aand the power supply device20bcan have external forms almost the same as that of a combined component of the conventional spring bar and the conventional wearing tool (without a battery or the like) such as a band, a belt, or a strap.

The power supply devices20aand20battached to the electronic device30function not only as wearing tools, but also as auxiliary power supplies or main power supplies of the electronic device30.

With the use of the power supply device20aor the power supply device20bof one embodiment of the present invention, it is not necessary to carry an auxiliary power supply separately; thus, the convenience is improved. In addition, the electronic device30to which the power supply device20aor20bis attached has no need to additionally connect an auxiliary power supply to itself unlike the conventional electronic device30provided with wearing tools. Therefore, although connected to the auxiliary power supply, the electronic device30to which the power supply device20aor20bis attached is compact and does not prevent movements of the user. In addition, there is no need to connect an auxiliary power supply to the electronic device30using a connector or the like; therefore, there is no danger that the auxiliary power supply comes out and drops. There is no need to provide the electronic device30with a terminal for the connector; therefore, a highly water resistant and highly designed electronic device can be achieved.

When the exterior body26of the battery22included in the power supply device20aand the power supply device20bhas an uneven surface, the reliability of the battery22which is subjected to repeated bending can be improved.

FIG.7Aillustrates an example in which the exterior body26has a mesh embossed surface.FIG.7Billustrates an example in which the exterior body26has a stripe embossed surface.

The exterior body26having an uneven surface is changed in shape so that the projected portions and the depressed portions on the outer side of a bent part are straightened and the projected portions and the depressed portions on the inner side of a bent part are compressed, when the battery22is bent. This can relieve stress applied to the exterior body26.

The above is the description of the power supply device.

Structure Example of Electronic Device

Specific structure examples of an electronic device that can receive power from the above power supply device will be described below.

FIG.8Ais a schematic view illustrating a main part of the electronic device30. The electronic device30includes a control portion61, a power supply control portion62, a functional circuit63, and the like in the housing31, and further includes the bearings34in the lugs33.

The bearings34are provided so as to face each other in one pair of the lugs33facing each other. The bearings34each have a function of fixing the connecting member10and function as a terminal to which a potential of the tip portion12aof the connecting member10is applied.

FIG.8Aillustrates an example in which the bearings34are provided for an upper pair of the lugs33and a lower pair of the lugs33in the housing31. The four bearings34are electrically connected to the power supply control portion62.

The power supply control portion62has a function of controlling charge and discharge of the power supply device20attached to the electronic device30, and further has a function of outputting power obtained from the power supply device20to the control portion61and the functional circuit63. The power supply control portion62may have a function of converting power supply voltage of the power supply device20into voltage suitable for being applied to the control portion61and the functional circuit63.

The control portion61has a function of controlling operations of the power supply control portion62and the functional circuit63.

As the functional circuit63, an input device or an output device can be used, for example. Examples of the input device include a variety of switches, a sensor (including a touch sensor or a biological sensor), an audio input device, and the like. Examples of the output device include a display device, an audio output device, a vibration device, a light-emitting device, and the like.

FIG.8Billustrates a more specific structure example of the electronic device30.FIG.8Bis a schematic view illustrating the inner structure of the electronic device30in a region R indicated by a dashed-dotted line inFIG.8A.

FIG.8Billustrates the electronic device30to which the connecting member10is connected.FIG.8Billustrates the conductive member25which is attached to the axis portion12cof the connecting member10and a tab42which is joined with the conductive member25. The exterior body21which covers the connecting member10, the conductive member25, and the tab42is illustrated by a broken line.

The bearing34provided in the lug33includes a terminal71into which the tip portion12aof the connecting member10fits. The terminal71is electrically connected to a wiring72.

It is preferable that a depressed portion into which the collar portion12bof the connecting member10fits be formed in part of the lug33as illustrated inFIG.8B. This can enhance the stability when the connecting member10is connected to the electronic device30.

FIG.8Billustrates an example in which the power supply control portion62has an IC chip form and is mounted on a substrate75. For example, a PCB or the like can be used as the substrate75. The bearing34and the substrate75are electrically connected to each other by the wiring72.

In addition, an FPC76aand an FPC76bare connected to the substrate75as an example here.

The FPC76ais electrically connected to a substrate on which the control portion61is mounted. The FPC76aincludes a wiring for applying a signal to the power supply control portion62from the control portion61, and a wiring for supplying power to the substrate on which the control portion61is mounted from the power supply control portion62, for example.

The FPC76bis electrically connected to the functional circuit63or a substrate on which the functional circuit63is mounted, for example. Note that the number of the FPC76bmay be two or more. Alternatively, the FPC76bmay be divided and connected to a plurality of the functional circuits63. When the same power supply voltages are applied to the control portion61and the functional circuit63, the FPC76bmay be divided and the divided part may be partly connected to the substrate on which the control portion61is mounted.

This structure makes it possible to control charge and discharge of the battery22(not illustrated) included in the power supply device20via the connecting member10and the bearing34when the power supply device20is connected to the electronic device30.

Here, the bearing34preferably includes a gasket for preventing water or dusts from entering the housing31. The provision of the gasket is particularly effective because there is a danger that the battery22is electrically shorted and high current flows if water touches the terminal71of the bearing34.

FIGS.8C and8Deach are an enlarged view of the bearing34.FIG.8Cillustrates an example in which a cushioning portion73ais provided at a portion of the lug33into which the collar portion12bfits.FIG.8Dillustrates an example in which a ring-shaped cushioning material73bis provided between the lug33and the collar portion12b. An elastic body such as rubber, for example, is suitably used for the cushioning portion73aand the cushioning material73b. Grease or the like may be applied to a surface of the cushioning portion73aor73b.

[Regarding System]

A configuration example of a system including the electronic device30, the power supply device20, and the connecting member10and an example of a method for controlling charge and discharge of batteries included in the electronic device30and the power supply device20will be described below.

(Configuration Example of System)

FIG.9Ais a block diagram of a system50described as an example below. The system50includes the electronic device30and the power supply device20.

Although the block diagram attached to this specification shows components classified by their functions in independent blocks, it is difficult to classify actual components according to their functions completely and it is possible for one component to have a plurality of functions.

The configuration of the system50illustrated inFIG.9Ais a mere example, and does not need to include all the components. The system50includes necessary components among the components illustrated inFIG.9Aand may include a component other than the components inFIG.9A.

The electronic device30includes the control portion61, the power supply control portion62, the functional circuit63, a sensor64, a battery65, a power receiving portion66, the bearing34, and the like. The power supply device20includes the connecting member10, the battery22, and the like.

Description on the power supply device20and the connecting member10is omitted because the above description can be referred to.

The control portion61can function as, for example, a central processing unit (CPU). The control portion61has a function of controlling components such as the power supply control portion62, the sensor64, and the functional circuit63.

The power receiving portion66has a function of receiving power supplied from the outside and supplying the power to the power supply control portion62.

At the time of charging, a battery charger capable of supplying power to the power receiving portion66can be used. At this time, the power receiving portion66may receive power through wires using a USB connector, an AC adaptor, or the like; alternatively, the power receiving portion66may receive power by a wireless power feeding method such as an electric field coupling method, an electromagnetic induction method, or an electromagnetic resonance (electromagnetic resonant coupling) method.

A power generating device may be provided for the electronic device30and used as one of the power receiving portions66. A solar cell can be typically used as the power generating device, and the power generating device can be provided to overlap with part of the display portion32or part of the housing31(including the lug33). Alternatively, a device which generates power when the electronic device30is shaken for example, a device which generates power when the power supply device20is bent and straightened for example, may be used as the power generating device.

The battery65serves as a main power supply of the electronic device30. Charge and discharge of the battery65is controlled by the power supply control portion62.

The power supply control portion62has a function of controlling charge and discharge of the battery65and the battery22. The power supply control portion62preferably has a function of transmitting information of, for example, remaining battery power levels of the battery65and the battery22to the control portion61.

The sensor64has a function of obtaining a potential difference between the pair of bearings34and of outputting the information to the control portion61. A digital signal corresponding to the potential difference between the bearings34may be output to the control portion61using a comparison circuit or the like, for example. Alternatively, an analog signal corresponding to the potential difference between the bearings34may be output to the control portion61. At this time, an analog-digital converter circuit is preferably used between the sensor64and the control portion61.

In addition, the sensor64may have a function of outputting a signal to the control portion61in the case where the potential difference between the pair of bearings34is outside a predetermined range. For example, when the potential difference is over a voltage of the fully-charged state of the battery22specified according to a rated voltage range or the like or when the potential difference is under a voltage in the discharged state, a signal is output to the control portion61.

The sensor64may have a function of sensing insertion of the connecting member10, the normal spring bar, or the like into the pair of bearings34and outputting the sensed information. A sensor in which a light-receiving element and a light source are combined, a physical switch, or the like can be used, for example. When it is determined that nothing is inserted into the pair of bearings34, the electronic device30can use the battery65as the power supply.

FIG.9Billustrates examples of components which can be used for the functional circuit63. As the functional circuit63, a display device, a memory device, a sound controller, a communication module, a posture detection module, an external interface, a camera module, a vibration module, or a variety of sensor modules can be given. Note that all of these components are not necessarily used as the functional circuit63. In addition, a component other than these components may be used as the functional circuit63. As the functional circuit63, a variety of components can be used in combination depending on the structure, function, usage, or the like of the electronic device30.

Each component which can be used as the functional circuit63is connected to the control portion61via a bus line69. In addition, power is supplied to each of the components from the power supply control portion62via a power supply line68.

The above is the description of the configuration example of the system.

Components included in the system50will be described below.

(Control Portion)

The control portion61interprets and executes instructions from various programs with a processor to process various kinds of data and control programs. The programs that can be executed by the processor may be stored in a memory region of the processor or in the memory device.

A CPU and another microprocessor such as a digital signal processor (DSP) or a graphics processing unit (GPU) can be used alone or in combination as the control portion61. Furthermore, such a microprocessor may be obtained with a programmable logic device (PLD) such as a field programmable gate array (FPGA) or a field programmable analog array (FPAA).

Note that a transistor that includes an oxide semiconductor in a channel formation region and that has an extremely low off-state current can be used in an IC or the like included in the control portion61or another component. With the use of the transistor having an extremely low off-state current as a switch for holding electric charge (data) which flows into a capacitor serving as a memory element, a long data retention period can be ensured. By utilizing this characteristic for a register or a cache memory of the control portion61, normally-off computing is achieved where the control portion61operates only when needed and data on the previous processing is stored in the memory element in the rest of time; thus, power consumption of the electronic device30can be reduced.

The control portion61may include a main memory. The main memory can include a volatile memory, such as a random access memory (RAM), and a nonvolatile memory, such as a read only memory (ROM).

For example, a dynamic random access memory (DRAM) is used for the RAM included in the main memory, in which case a memory space as a workspace for the control portion61is virtually allocated and used. An operating system, an application program, a program module, program data, and the like which are stored in the memory device are loaded into the RAM and executed. The data, program, and program module which are loaded into the RAM are directly accessed and operated by the control portion61.

In the ROM, a basic input/output system (BIOS), firmware, and the like for which rewriting is not needed can be stored. As the ROM, a mask ROM, a one-time programmable read only memory (OTPROM), an erasable programmable read only memory (EPROM), or the like can be used. As an EPROM, an ultra-violet erasable programmable read only memory (UV-EPROM) which can erase stored data by irradiation with ultraviolet rays, an electrically erasable programmable read only memory (EEPROM), a flash memory, and the like can be given.

(Power Control Portion)

The power supply control portion62may include a battery management unit (BMU), for example. The BMU collects data on cell voltage or cell temperatures of the battery, monitors overcharge and overdischarge, controls a cell balancer, handles a deterioration state of the battery, calculates the remaining battery power level (state of charge: SOC), and controls detection of a failure, for example.

The power supply control portion62controls power transmission to the components through the bus line69or a power supply line. The power supply control portion62can include a power converter with a plurality of channels, an inverter, a protection circuit, and the like.

The power supply control portion62preferably has a function of reducing power consumption. As the function of reducing power consumption, for example, after detection of no input to the electronic device30for a given period, the power supply control portion62lowers clock frequency or stops input of clocks of the control portion61, stops operation of the control portion61itself, stops operation of the auxiliary memory, and reduces power consumption by reducing power supply to the components. Such a function can be performed by the power supply control portion62alone or the power supply control portion62interlocking with the control portion61.

(Battery)

Each of the battery65and the battery22includes one or more primary batteries or secondary batteries, for example. Examples of the secondary battery which can be used as the battery65include a lithium-ion secondary battery, or a lithium-ion polymer secondary battery. In addition to such a battery, the battery65may be provided with a protection circuit for preventing overcharge and overdischarge or the like.

In the case of indoor use or the like, power supplied by the battery65and the battery22is not used and an external power supply such as an alternating-current (AC) power supply may be used. Power supplied by a wireless power feeding may be used.

As the battery65and the battery22, batteries including a coin-type (or button-type) exterior body, a cylindrical exterior body, or a prismatic exterior body can be used. In particular, the coin-type battery, which is light and thin, is preferably used as the battery65in a wearable device.

Flexible batteries are preferably used as the battery65and the battery22. Especially for the battery22, such a battery is preferably used.

Examples of the secondary battery which can be used for the flexible battery include a lithium-ion secondary battery, or a lithium-ion polymer secondary battery. It is preferable that a laminate pouch be used as an exterior package of the battery so that the battery has flexibility.

A film used for the laminate pouch is a single-layer film selected from a metal film (e.g., an aluminum film, a stainless steel film, or a nickel steel film), a plastic film made of an organic material, a hybrid material film containing an organic material (e.g., an organic resin or fiber) and an inorganic material (e.g., ceramic), and a carbon-containing inorganic film (e.g., a carbon film or a graphite film), or a stacked-layer film including two or more of the above films. A metal film can be easily embossed. Forming depressions or projections on a surface of a metal film by embossing increases the surface area of the film exposed to outside air, achieving efficient heat dissipation.

It is particularly preferable that a laminate pouch including a metal film having depressions and projections by embossing be used, in which case a strain caused by stress applied to the laminate pouch can be relieved, leading to an effective decrease of defects such as a break of the laminate pouch due to bending of the secondary battery.

(Functional Circuit)

An example of a component that can be used for the functional circuit63will be described below.

<Display Device>

As the display device, a segment-type display device, a passive-matrix-type display device, an active-matrix-type display device, or the like can be used. In addition, a touch panel functioning as a touch sensor is preferably used for the display portion.

The display device includes a display panel and a display controller. When a touch panel is used in the display device, the display panel can include a touch panel, a display controller, and a touch sensor controller. Note that the display controller serves also as a touch panel controller in some cases in an in-cell-type touch panel or the like. The details especially of the case where the touch panel is used will be described below.

A touch panel is connected to a display controller and a touch sensor controller. The display controller and the touch sensor controller are connected to the control portion61via the bus line69.

The display controller controls the touch panel in response to drawing instructions input from the control portion61via the bus line69so that a predetermined image is displayed on the display surface of the touch panel.

The touch sensor controller controls a touch sensor of the touch panel in response to requests input from the control portion61via the bus line69. In addition, the touch sensor controller outputs a signal received by the touch sensor to the control portion61via the bus line69. Note that the function of calculating touch position information from a signal received by the touch sensor may be given to the touch sensor controller or the control portion61.

The touch panel can display an image on the basis of a signal supplied from the display controller. In addition, the touch panel is capable of sensing the proximity or touch of an object such as a finger or a stylus on the basis of a signal supplied from the touch sensor controller and of outputting the positional information of the object to the touch sensor controller.

The touch sensor and the touch sensor controller preferably have a function of obtaining the distance between a sensing surface and the object in the height direction, a function of obtaining the level of pressure applied to the sensing surface by the object, and a function of obtaining the size of the surface of the sensing surface that is in contact with the object.

In the touch panel, a module including the touch sensor can be provided on the display surface side of the display panel so as to overlap with the display panel. In that case, at least a portion of the module including the touch sensor is preferably flexible to follow the bending of the display panel. The module including the touch sensor can be bonded to the display panel with an adhesive or the like. A polarizing plate or a cushioning material (e.g., a separator) may be provided between the module and the display panel. The thickness of the module including the touch sensor is preferably less than or equal to that of the display panel.

A touch panel in which a display panel and a touch sensor are combined may be used as the touch panel. For example, the touch panel is preferably an on-cell touch panel or an in-cell touch panel. The on-cell or in-cell touch panel has a small thickness and therefore can be lightweight. In addition, the number of components of the on-cell or in-cell touch panel can be reduced, so that cost can be reduced.

A variety of sensors capable of sensing the proximity or touch of an object such as a finger can be used as the touch sensor included in the touch panel. For example, a sensor of a capacitive type, a resistive type, a surface acoustic wave type, an infrared type, or an optical type can be used. In addition, an optical sensor using a photoelectric conversion element, a pressure-sensitive sensor using a pressure-sensitive element, or the like may be used. Two or more sensors of different types may be used, or two or more sensors of the same type may be used.

Examples of the capacitive touch sensor are a surface capacitive touch sensor and a projected capacitive touch sensor. Examples of the projected capacitive touch sensor include a self-capacitive touch sensor and a mutual capacitive touch sensor. The use of the mutual capacitive touch sensor is preferable because simultaneous detection of multiple points can be performed easily.

A flexible touch panel, display panel, touch sensor, and the like can be used. This can be achievable, for example, when a flexible substrate is used as a substrate supporting a display element, a circuit for driving the display element, a circuit included in a touch sensor, and the like.

A typical example of a material of a flexible substrate is an organic resin. In addition, glass, metal, alloy, a semiconductor, or the like that is thin enough to have flexibility, or a composite material or a stacked material containing two or more of an organic resin, glass, metal, alloy, a semiconductor, and the like can be used.

As the display element included in the touch panel, a self-luminous light-emitting element such as an organic light-emitting diode (OLED), a light-emitting diode (LED), or a quantum-dot light-emitting diode (QLED) can be used. Alternatively, a transmissive, reflective, or semi-transmissive liquid crystal element may be used. Besides, for example, a display element such as a micro electro mechanical systems (MEMS) element or an electron emitter can be used. Examples of MEMS display elements include a MEMS shutter display element, an optical interference type MEMS display element, and the like. A carbon nanotube may be used for the electron emitter. Alternatively, electronic paper may be used. As the electronic paper, an element using a microcapsule method, an electrophoretic method, an electrowetting method, an Electronic Liquid Powder (registered trademark) method, or the like can be used.

<Memory Device>

Examples of the memory device are a memory device including a nonvolatile memory element, such as a flash memory, a magnetoresistive random access memory (MRAM), a phase change RAM (PRAM), a resistance RANI (ReRAM), or a ferroelectric RAM (FeRAM), and a memory device including a volatile memory element, such as a dynamic RAM (DRAM) or a static RAM (SRAM). Alternatively, a storage media drive such as a hard disk drive (HDD) or a solid state drive (SSD) may be used, for example.

As the memory device, a memory device which can be connected to and disconnected from an external interface with a connector, such as an HDD or an SSD, or a storage media drive, such as a flash memory, a Blu-ray disc, or a DVD can also be used. Note that the memory device is not necessarily incorporated in the electronic device30, and a memory device outside the electronic device30may be used. In this case, the memory device may be connected through the external interface, or data transmission and reception may be wirelessly performed using a communication module.

<Sound Controller>

A sound controller has a function of controlling an audio input portion and an audio output portion. The audio input portion includes a microphone, an audio input connector, or the like, for example. The audio output portion includes a speaker, an audio output connector, or the like, for example. The audio input portion and the audio output portion are connected to the sound controller, and are connected to the control portion61via the bus line69. Audio data input to the audio input portion is converted into a digital signal in the sound controller and then processed in the sound controller and the control portion61. In contrast, the sound controller generates an analog audio signal audible to a user in response to instructions from the control portion61and outputs the analog audio signal to the audio output portion. To the audio output connector of the audio output portion, an audio output device such as earphones, headphones, or a headset can be connected and a sound generated in the sound controller is output to the device.

<Communication Module>

The communication module can communicate via an antenna. For example, the communication module controls a control signal for connecting the electronic device30to a computer network in response to instructions from the control portion61and transmits the signal to the computer network. Accordingly, communication can be performed by connecting the electronic device30to a computer network such as the Internet, which is an infrastructure of the World Wide Web (WWW), an intranet, an extranet, a personal area network (PAN), a local area network (LAN), a campus area network (CAN), a metropolitan area network (MAN), a wide area network (WAN), or a global area network (GAN). When a plurality of communication methods are used, the electronic device30may have a plurality of antennas for the communication methods.

For example, a high frequency circuit (RF circuit) is included in the communication module for transmitting and receiving an RF signal. The high frequency circuit performs conversion between an electromagnetic signal and an electric signal in a frequency band which is set by respective national laws and performs communication with another communication device wirelessly with the use of the electromagnetic signal. Several tens of kilohertz to several tens of gigahertz is a practical frequency band which is generally used. The high frequency circuit connected to an antenna includes a high frequency circuit portion compatible with a plurality of frequency bands; the high frequency circuit portion can include an amplifier, a mixer, a filter, a DSP, an RF transceiver, or the like. The following communication protocol or communication technology for wireless communication can be used: a communications standard such as Long Term Evolution (LTE), Global System for Mobile Communication (GSM) (registered trademark), Enhanced Data Rates for GSM Evolution (EDGE), Code Division Multiple Access 2000 (CDMA2000), or Wideband Code Division Multiple Access (W-CDMA) (registered trademark), or a communications standard developed by IEEE such as Wi-Fi (registered trademark), Bluetooth (registered trademark), or ZigBee (registered trademark).

The communication module may have a function of connecting the electronic device30to a telephone line. In the case of a telephone call through the telephone line, the communication module controls a connection signal for connecting the electronic device30to the telephone line in response to instructions from the control portion61and transmits the signal to the telephone line.

The communication module may include a tuner generating an image signal from airwaves received by the antenna. The image signal is output to the touch panel or the like. For example, the tuner can include a demodulation circuit, an analog-digital (AD) converter circuit, a decoder circuit, and the like. The demodulation circuit has a function of demodulating a signal input from the antenna. The AD converter circuit has a function of converting the demodulated analog signal into a digital signal. The decoder circuit has a function of decoding image data contained in the digital signal and generating a signal to be transmitted to a display controller.

Alternatively, a decoder may include a dividing circuit and a plurality of processors. The dividing circuit has a function of dividing the input image data spatiotemporally and outputting it to the processors. The plurality of processors decode the input image data and generate signals to be transmitted to the display controller. Since the decoder includes the plurality of processors which perform parallel data processing, image data containing enormous amounts of information can be decoded. Particularly in the case of displaying an image with a resolution higher than the full high definition, a decoder circuit for decoding compressed data preferably includes a processor having extremely high-speed processing capability. The decoder circuit preferably includes a plurality of processors capable of performing 4 or more, preferably 8 or more, further preferably 16 or more parallel operations. The decoder may include a circuit for classifying an image signal contained in the input signal from other signals (e.g., text information, broadcast program information, and certification information).

The antenna can receive airwaves such as a ground wave and a satellite wave. The antenna can receive airwaves for analog broadcasting, digital broadcasting, and the like, and image-sound-only broadcasting, sound-only broadcasting, and the like. For example, the antenna can receive airwaves transmitted in a certain frequency band, such as a UHF band (about 300 MHz to 3 GHz) or a VHF band (30 MHz to 300 MHz). When a plurality of pieces of data received in a plurality of frequency bands is used, the transfer rate can be increased and more information can thus be obtained. Accordingly, an image with resolution higher than the full high definition, such as 4K-2K, 8K-4K, 16K-8K, or higher, can be displayed on a touch panel or the like.

Alternatively, the tuner may be configured to generate a signal using the broadcasting data transmitted with data transmission technology through a computer network. The signal is transmitted to the display controller. In the case where the tuner receives a digital signal, the tuner does not necessarily include the demodulation circuit and the AD converter circuit.

<Posture Measurement Module>

The posture measurement module has a function of measuring a tilt, a posture, and the like of the electronic device30. For example, an acceleration sensor, an angular velocity sensor, a vibration sensor, a pressure sensor, a gyroscope sensor, or the like can be used for the posture measurement module. Alternatively, these sensors may be combined.

<External Interface>

Examples of the external interface include one or more buttons or switches (also referred to as housing switches) and an external port to which another input component can be connected which are provided on the housing31. The external interface is connected to the control portion61via the bus line69. Examples of the housing switch include a switch which links with powering on/off, a button for adjusting volume, and a camera button.

The external port of the external interface can be connected to an external device such as a computer, a printer, a video reproducing device, for example, through a cable. An universal serial bus (USB) terminal is a typical example. As the external port, a local area network (LAN) connection terminal, a digital broadcasting reception terminal, an AC adaptor connection terminal, or the like may be provided. A transceiver for optical communication, without limitation to wire communication, using infrared rays, visible light, ultraviolet rays, or the like, may be provided.

<Camera Module>

A camera module has a function of taking still images and moving images. The camera module is connected to the control portion61via the bus line69, for example. The camera module can take a still image or a moving image in synchronization with pushing a switch provided on the housing or touching the touch panel, for example. The camera module may include a light source for taking images. For example, a lamp such as a xenon lamp, a light-emitting element such as an LED or an organic EL element, or the like can be used. Alternatively, the touch panel may be used as the light source for taking images, in which case light with a variety of colors in addition to white may be used for taking images.

<Vibration Module>

The vibration module includes a vibrating element for vibrating the electronic device30and a vibration controller for controlling the vibrating element. As the vibrating element, an element capable of converting an electric signal or a magnetic signal into vibration, such as a vibration motor (eccentric motor), a resonant actuator, a magnetostrictive element, or a piezoelectric element can be used.

The vibration module can vibrate the electronic device30in accordance with a variety of vibration patterns by controlling the number of vibrations, the amplitude, vibration time, and the like of the vibrating element according to instructions from the control portion61. The vibration module can generate vibration with a variety of vibration patterns based on operation executed by a variety of applications. Examples of such vibration include vibration linked with operation of the housing switch or the like, vibration linked with startup of the electronic device30, vibration linked with a moving image or audio reproduced by an application for reproducing a moving image, vibration linked with reception of an e-mail, and vibration linked with input operation to the touch panel.

<Sensor Module>

The sensor module includes a sensor unit and a sensor controller. The sensor controller supplies power from the battery module or the like to the sensor unit. Moreover, the sensor controller converts the input from the sensor unit into a control signal and outputs it to the control portion61via the bus line69. The sensor controller may handle errors made by the sensor unit or may calibrate the sensor unit. Note that the sensor controller may include a plurality of controllers for controlling the sensor unit.

The sensor module may include any of a variety of sensors which measure force, displacement, position, speed, acceleration, angular velocity, rotational frequency, distance, light, liquid, magnetism, temperature, a chemical substance, a sound, time, hardness, electric field, current, voltage, electric power, radiation, flow rate, humidity, gradient, vibration, smell, and infrared rays.

In addition, as a sensor included in the sensor module, a sensor which obtains biological information can be used. Examples of biological information include body temperature, blood pressure, pulse rate, the amount of sweat, lung capacity, blood sugar level, blood alcohol concentration, SpO2(blood oxygen saturation), and the like. Obtaining such biological information enables the electronic device30to be used as a healthcare system.

In addition, as the sensor included in the sensor module, a sensor which obtains biological information of fingerprints, veins, iris, voice prints, or the like can also be used. The use of such a sensor enables biometric identification function to be performed and can prevent unauthorized use of the electronic device30by others, so that the security level can be increased.

The above is the description of examples of components that can be used as the functional circuit63.

Example of Operation Method of System

Next, operation of the system50illustrated inFIG.9Awill be described.

Operation Method Example 1

FIG.10is a flow chart of an operation of the system50.FIG.10is an example in which the operation is performed so that power of either the battery22or the battery65is used. The following operations are mainly performed by the control portion61.

First, the operation starts in Step S00. The operation is started when the electronic device30is turned on or the system50is set to be effective by the user, for example. Alternatively, the operation may be started when the connecting member10or a component such as the conventional spring bar is attached to or detached from the bearings34, for example.

Next, information of a potential of the pair of bearings34(hereinafter, also referred to as potential information) is obtained in Step S01. Specifically, the control portion61controls the sensor64to obtain information of a potential between the pair of bearings34. The sensor64outputs the obtained potential information to the control portion61.

Next, whether the pair of bearings34are electrically shorted or insulated from each other or not is determined in Step S02. When it is determined that the pair of bearings34are electrically shorted or insulated from each other, Step S02is shifted to Step S05, and when it is determined that the pair of bearings34are not electrically shorted and insulated from each other, Step S02is shifted to Step S03.

Step S02corresponds to a step for determining whether the power supply device20is connected to the electronic device30or not.

Specifically, when a potential difference between the pair of bearings34is 0 V or in the neighborhood thereof, it is determined that the pair of bearings34are electrically shorted or insulated from each other. At this time, it can be determined that the power supply device20provided with the battery22is not connected to at least the pair of bearings34.

In contrast, when a potential difference between the pair of bearings34is higher than or equal to 0.5 V, higher than or equal to 1 V, or the like, it is determined that the pair of bearings34are not electrically shorted and insulated from each other. At this time, it can be determined that the power supply device20is connected to the pair of bearings34.

Next, whether a potential difference of the pair of bearings34is in a range of a given potential difference or not is determined in Step S03. When it is in the range of the given potential difference, Step S03is shifted to Step S04; in contrast, when it is not in the range of the given potential difference, Step S03is shifted to Step S05.

Step S03corresponds to a step for checking the remaining power level of the battery22in the power supply device20. The remaining power level of the battery22can be measured here using a value of output voltage in a range specified according to a rated voltage range or the like. For example, in the rated voltage range, it can be assumed that fully-charged voltage is 100% and discharged voltage is 0%. At this time, in Step S03, it can be determined that the remaining power level of the battery22is not enough when a potential difference between the pair of bearings34is higher than or equal to 0% and lower than 5% or higher than or equal to 0% and lower than 3% of the potential difference in the rated voltage range.

Step S03also corresponds to a step for excluding output voltage of the battery22when the voltage is beyond an expected voltage range. In the case where the output voltage of the battery22is beyond the expected voltage, components in the electronic device30might be broken. For example, when the potential difference of the pair of bearings34is beyond the maximum value, set in advance, of voltage that can be input to the electronic device30, it is determined that the potential difference is not in the range of the given potential difference.

Note that the remaining power level of the battery22is measured using, but not limited to, the potential difference between the pair of bearings34. The remaining power level may be measured using the current amount, the power amount, or the like.

Next, whether power supplied from the bearings34is used or not is determined in Step S04. When the power is used, Step S04is shifted to Step S06; when it is not used, Step S04is shifted to Step S05.

In Step S04, the operation of the control portion61can be specified in accordance with setting information that is set in advance. The setting information may be set in advance before shipment. In addition, the setting information may be changeable by the user. In addition, a condition that power supplied from the bearings34is used when the remaining power level of the battery65becomes lower than 10%, or the like may be added to the setting information.

In Step S05, the electronic device30is driven using power by the battery65included in the electronic device30. Specifically, the control portion61controls the power supply control portion62so that power supplied from the battery65is output to the components. After that, Step S05is shifted to Step S07.

In Step S06, the electronic device30is driven using power supplied from the pair of bearings34. Specifically, the control portion61controls the power supply control portion62so that power input from the battery22included in the power supply device20via the connecting member10and the bearings34is output to the components. After that, Step S06is shifted to Step S07.

In Step S07, the operation is completed.

The above is the description of the flow shown inFIG.10.

The use of the method illustrated here makes it possible to easily determine which is connected to the pair of bearings34, the power supply device20including the battery22and the connecting member10or a normal wearing tool not including them. When the normal wearing tool is connected to the pair of bearings34, the electronic device30can be driven using the battery65included in the electronic device30itself as the power supply.

Operation Method Example 2

FIG.11is a flow chart of an operation of the system50.FIG.11is a flow chart of an operation for charging the battery22and the battery65. In particular,FIG.11is an example of a case where the battery22is preferentially charged. The following operations are mainly performed by the control portion61.

First, the operation starts in Step S10.

Next, it is determined whether power is being received or not in Step S11Specifically, it is determined whether the power receiving portion66is receiving power or not. When power is being received, Step S11is shifted to Step S12; when power is not received, Step S11is shifted to Step S18.

In Step S12, positional information is obtained.

In Step S13, whether the pair of bearings34are electrically shorted or insulated from each other or not is determined. When it is determined that the pair of bearings34are electrically shorted or insulated from each other, Step S13is shifted to Step S17, and when it is determined that the pair of bearings34are not electrically shorted and insulated from each other, Step S13is shifted to Step S14.

In Step S14, it is determined whether a potential difference of the pair of bearings34is lower than a given potential difference or not. When it is lower than the given potential difference, Step S14is shifted to Step S15; in contrast, when it is higher than or equal to the given potential difference, Step S14is shifted to Step S17.

Step S14corresponds to a step for checking whether the battery22in the power supply device20is fully charged or not. For example, the given potential difference in Step S14can be set as a potential difference corresponding to that of a fully-charged state of the battery22(a state in which the output voltage is 100% in the rated voltage range).

In Step S15, power is output to the pair of bearings34, so that the battery22is charged. Specifically, the control portion61controls the power supply control portion62so that power supplied from the power receiving portion66is output to the pair of bearings34. The power supply control portion62gives a potential difference for charging the battery22to the pair of bearings34. This makes it possible to charge the battery22via the connecting member10. After that, Step S15is shifted to Step S16.

Step S15is continued until the battery22becomes fully-charged or in the neighborhood state. Specifically, charge is completed when the potential difference between the pair of bearings34is equal to the potential difference corresponding to that of the fully-charged battery22or higher than or equal to 95% of the potential difference. In contrast, charge is continued when the potential difference corresponds to a potential difference of a state where the charged state of the battery is lower than 100% or lower than 95%.

In Step S16, it is determined whether the battery65has been completely charged or not. When the battery65has been completely charged, Step S16is shifted to Step S18. In contrast, when the battery65has not been completely charged, Step S16is shifted to Step S17.

Specifically, it is determined that the battery65has been completely charged when its charged state is a fully-charged state or higher than or equal to 95%. In contrast, it is determined that the battery65has not been completely charged when the charged state is lower than 100% or 95%.

In Step S17, power is output to the battery65, so that the battery65is charged. Specifically, the control portion61controls the power supply control portion62so that power supplied from the power receiving portion66is output to the battery65. After that, Step S17is shifted to Step S18.

Step S17is continued until the battery65becomes fully-charged or in the neighborhood state, as in Step S15.

In Step S18, the operation is completed. At this point, the battery22and the battery65have been completely charged.

The above is the description of the operation method example 2.

Operation Method Example 3

FIG.12is a flow chart of an operation of the system50.FIG.12is a flow chart of an operation for charging the battery22and the battery65. In particular,FIG.12is an example of a case where the battery65is preferentially charged. The following operations are mainly performed by the control portion61.

First, the operation starts in Step S20.

Next, it is determined whether power is being received or not in Step S21. When power is being received, Step S21is shifted to Step S22; when power is not received, Step S21is shifted to Step S27.

In Step S22, power is output to the battery65, so that the battery65is charged. Specifically, the control portion61controls the power supply control portion62so that power supplied from the power receiving portion66is output to the battery65. After the battery65is completely charged, Step S22is shifted to Step S23.

In Step S23, positional information is obtained.

In Step S24, whether the pair of bearings34are electrically shorted or insulated from each other or not is determined. When it is determined that the pair of bearings34are electrically shorted or insulated from each other, Step S24is shifted to Step S27, and when it is determined that the pair of bearings34are not electrically shorted and insulated from each other, Step S24is shifted to Step S25.

In Step S25, it is determined whether the potential difference of the pair of bearings34is lower than a given potential difference or not. When it is lower than the given potential difference, Step S25is shifted to Step S26; in contrast, when it is higher than or equal to the given potential difference, Step S25is shifted to Step S27.

The above description can be referred to for the standards for determination of Step S25.

In Step S26, power is output to the pair of bearings34, so that the battery22is charged. After the battery22is completely charged, Step S26is shifted to Step S27.

In Step S27, the operation is completed. At this point, the battery22and the battery65have been completely charged.

The above is the description of the operation method example 3.

Two methods for charging the battery22and the battery65are described here. Either method may be selected in accordance with which battery is preferentially charged. In addition, which method is used may be set in advance as the setting information or may be changeable by the user.

Note that one embodiment of the present invention may be achieved in such a manner that a program is stored in a memory portion included in the electronic device30and read out and executed by the control portion61. That is, another embodiment of the present invention is a program which makes the control portion61to perform the operations of the above flow.

The above is the description of the operation method examples of the system.

Application

Although a watch-type information terminal is described above as an example of an electronic device in which the connecting member, power supply device, and the like of one embodiment of the present invention can be used, the electronic device is not limited thereto. The connecting member, the power supply device, and the like can be used in various electronic devices. Examples of an electronic device which is different from the above will be described below.

The power supply device of one embodiment of the present invention can be used for various usages because of its characteristics of the band shape, the flexibility, or the like. For example, the power supply device can be used as a wearing tool for wearing the device on the arm, foot, west, or the like. In addition, the power supply device can be used for parts of the device serving as its handle or a strap for being suspended from the shoulder or neck, or can be used as an accessary, like a cell phone charm, which is also used to prevent slipping down.

Examples of a device in which the power supply device of one embodiment of the present invention can be used include wearable devices such as a watch-type electronic device, a glasses-type electronic device, a head mounted display (HMD), and the like. In addition, the power supply device can be favorably used for a biological information device such as blood pressure meter, an electrocardiograph, and a pedometer. In addition, the following various electronic devices can be given: a mobile information terminal such as a mobile phone, a smart phone, and a tablet device; a digital camera; an audio reproducing device; a moving image reproducing device; a communication device such as a mobile router; wireless earphones; wireless headphones; a speaker; and the like.

The power supply device can be used not only for electronic devices, but also for bags, clothes (including hats), and the like. The power supply device of one embodiment of the present invention can be used for bags or clothes without injuring its lightweight or fittability because of its thinness, lightweight, and flexibility.

For example, a bag whose handle or strap includes the power supply device of one embodiment of the present invention serves as a charger for charging electronic devices which are carried in the bag. In addition, various functions using power such as a communication function, a function of transmitting a sound or vibration, or the like can be added to the bag itself, for example.

The power supply device included in clothes can add a function of obtaining biological information by an electrode or sensor provided in the clothes, can change its design by emitting light from part of the clothes or displaying an image on part of the clothes, and can extend the clothes.

The power supply device of one embodiment of the present invention can be easily attached and detached and can be easily detached when the clothes are washed, for example; therefore, risks of shorting the battery or the like can be prevented.

FIGS.13A and13Bare external views of a head-mounted display300.

The head-mounted display300includes a housing301, a display portion302, and an operation button303. The strap-like power supply device20is attached to the housing301. The power supply device20includes the battery22.

The head-mounted display300can use a battery provided in the housing301and the battery22provided in the power supply device20as its power supply.

The head-mounted display300may include a power generating device such as a solar cell in the housing301. A device which generates power when the head-mounted display300is shaken for example, a device which generates power when the power supply device20is bent and straightened for example, may be used as the power generating device.

The housing301includes a wireless receiver, a connector, or the like to receive video data, such as image data, and display it on the display portion302. The head-mounted display preferably has a function of sensing the movement of the user's head or the like with an acceleration sensor or the like included in the housing301to move an image displayed on the display portion302in synchronization with the movement of the user's head or the like.

The movement of the eyeball and the eyelid of a user is captured by a camera in the housing301and then coordinates of the points the user looks at are calculated using the captured data to utilize the eye of the user as an input means. The housing301may include a plurality of electrodes to be in contact with the user. The housing301may be configured to sense current flowing through the electrodes with the movement of the user's eyeball to recognize the direction of his or her eyes. The housing301may be configured to sense current flowing through the electrodes to monitor the user's pulse. The housing301may include sensors, such as a temperature sensor, a pressure sensor, or an acceleration sensor, so that the user's biological information can be displayed on the display portion302.

The operation button303serves as a power button or the like. A button other than the operation button303may be included.

As illustrated inFIG.13C, lenses305may be provided between the display portion302and the user's eyes. With the lenses305, the user can see magnified images on the display portion302; thus, the realism is further increased. In this case, as illustrated inFIG.13C, a dial306for adjusting the position of the lenses may be included to adjust visibility.

The display portion302can display an image for the right eye and an image for the left eye side by side on a right region and a left region, respectively. Thus, a three-dimensional image using binocular disparity can be displayed.

One binocular visible image may be displayed on the entire region of the display portion302. A panorama image can thus be displayed from end to end of the field of view; therefore, the sense of reality is increased.

With the lenses305provided as illustrated inFIG.13C, two images may be displayed side by side on the display portion302; alternatively, one image may be displayed on the display portion302and seen by both eyes through the lenses305.

FIG.13Dillustrates an example in which a curved display is used as the display portion302. This structure can perform more realistic display than the case where a display having a flat display surface is used.

FIG.13Eillustrates an example in which two displays, a right-eye display and a left-eye display, are provided as the display portions302.

With the two display portions302, the user can see one of the display portions302with one eye. Thus, a high-resolution image can be displayed even when a three-dimensional display using parallax or the like is performed. In addition, the display portions302are each curved around an arc with the user's eye as an approximate center. Owing to this, the distance between the user's eye and the display surface of the display portion302is uniform; thus, the user can see a more natural image. Even when the directivity of light emitted from the display portion302is high and the luminance or chromaticity of the light is changed depending on the angle at which the user see it, the influence of the change can be substantially ignorable and thus a more realistic image can be displayed because the user's eye is positioned in a normal direction of the display surface of the display portion302.

FIG.14Aillustrates an example of a mobile information terminal. A mobile information terminal310illustrated inFIG.14Aincludes a housing311, a display portion312, an operation button313, an external connection port314, a speaker315, a microphone316, a camera317, and the like. The band-like power supply device20is attached to the housing311. The power supply device20includes the battery22.

The mobile information terminal310can use a battery provided in the housing311and the battery22provided in the power supply device20as its power supply.

The mobile information terminal310may include a power generating device such as a solar cell in the housing311. A device which generates power when the mobile information terminal310is shaken for example, a device which generates power when the power supply device20is bent and straightened for example, may be used as the power generating device.

The mobile information terminal310includes a touch sensor in the display portion312. Operations such as making a call and inputting a letter can be performed by touch on the display portion312with a finger, a stylus, or the like.

With the operation button313, the power can be switched on and off. In addition, types of images displayed on the display portion312can be switched; for example, switching images from a mail creation screen to a main menu screen is performed with the operation button313.

When a sensing device such as a gyroscope sensor or an acceleration sensor is provided inside the mobile information terminal310, the direction of display on the screen of the display portion312can be automatically changed by determining the orientation of the mobile information terminal310(whether the mobile information terminal is placed horizontally or vertically). Furthermore, the direction of display on the screen can be changed by touch on the display portion312, operation with the operation button313, sound input using the microphone316, or the like.

The mobile information terminal310has a function as, for example, one or more of a telephone set, a notebook, and an information browsing system. Specifically, the mobile information terminal310can be used as a smartphone. The mobile information terminal310is capable of executing a variety of applications such as mobile phone calls, e-mailing, viewing and editing texts, music reproduction, moving image reproduction, Internet communication, and computer games, for example.

FIG.14Billustrates an example of a camera. A camera320includes a housing321, a display portion322, operation buttons323, a shutter button324, and the like. Furthermore, an attachable lens326is attached to the camera320. The band-like power supply device20is attached to the housing321. The power supply device20includes the battery22.

The camera320can use a battery provided in the housing321and the battery22provided in the power supply device20as its power supply.

The camera320may include a power generating device such as a solar cell in the housing321. A device which generates power when the camera320is shaken for example, a device which generates power when the power supply device20is bent and straightened for example, may be used as the power generating device.

Although the lens326of the camera320here is detachable from the housing321for replacement, the lens326may be included in the housing.

The camera320can shoot still images or moving images when the shutter button324is pressed. In addition, the display portion322functions as a touch panel, and shooting can also be performed when the display portion322is touched.

Note that the camera320can be additionally provided with a stroboscope, a viewfinder, or the like. Alternatively, they may be incorporated in the housing321.

The above is the description of the application examples.

This embodiment can be implemented in combination with any of the other embodiment described in this specification as appropriate.

Embodiment 2

Structure examples and manufacturing method examples of a secondary battery that can be used for the battery22of one embodiment of the present invention, or the like will be described below with reference to drawings. In particular, an example of a bendable secondary battery will be described below.

Structure Example

FIG.15is a perspective view showing an appearance of the secondary battery102.FIG.16Ais a cross-sectional view taken along dashed-dotted line A1-A2inFIG.15.FIG.16Bis a cross-sectional view taken along dashed-dotted line B1-B2inFIG.15.

The secondary battery102of one embodiment of the present invention includes, in an exterior body507, a positive electrode511covered with a separator503, a negative electrode515, and an electrolyte solution504. In the example inFIG.15andFIGS.16A and16B, the secondary battery includes one positive electrode including a positive electrode active material layer502on one side of a positive electrode current collector501, one positive electrode including the positive electrode active material layer502on each side of the positive electrode current collector501, one negative electrode including a negative electrode active material layer506on one side of a negative electrode current collector505, and one negative electrode including the negative electrode active material layer506on each side of the negative electrode current collector505. The positive electrode511is electrically connected to a positive electrode lead521. The negative electrode515is electrically connected to a negative electrode lead525. Each of the positive electrode lead521and the negative electrode lead525is also referred to as a lead electrode or a lead terminal. Parts of the positive electrode lead521and the negative electrode lead525are positioned outside the exterior body. The secondary battery102is charged and discharged through the positive electrode lead521and the negative electrode lead525.

Note that althoughFIGS.16A and16Billustrate the example in which the positive electrode511is covered with the separator503, one embodiment of the present invention is not limited thereto. The positive electrode511is not necessarily covered with the separator503, for example. The negative electrode515, instead of the positive electrode511, may be covered with the separator503, for example.

(Positive Electrode)

The positive electrode511includes, for example, the positive electrode current collector501and the positive electrode active material layer502formed over the positive electrode current collector501. AlthoughFIGS.16A and16Billustrate the example of one positive electrode511including the positive electrode active material layer502on only one side of the positive electrode current collector501with a sheet shape (or a band-like shape) and one positive electrode511including the positive electrode active material layer502on each side of the positive electrode current collector501, one embodiment of the present invention is not limited thereto. Only the positive electrodes511each including the positive electrode active material layer502on only one side of the positive electrode current collector501may be used. Only the positive electrodes511each including the positive electrode active material layer502on each side of the positive electrode current collector501may be used. With the use of the positive electrodes511including the positive electrode active material layer502on each side of the positive electrode current collector501allows the secondary battery102to have high capacity. In addition, the secondary battery102may include three or more positive electrodes511. An increase in the number of the positive electrodes511in the secondary battery102can increase the capacity of the secondary battery102.

The positive electrode current collector501can be formed using a material that has high conductivity and does not dissolve at the potential of the positive electrode, such as a metal typified by stainless steel, gold, platinum, aluminum, or titanium, or an alloy thereof. Alternatively, an aluminum alloy to which an element which improves heat resistance, such as silicon, titanium, neodymium, scandium, or molybdenum, is added can be used. Still alternatively, a metal element which forms silicide by reacting with silicon can be used. Examples of the metal element which forms silicide by reacting with silicon are zirconium, titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, nickel, and the like. The positive electrode current collector501can have a foil-like shape, a plate-like shape (a sheet-like shape), a net-like shape, a punching-metal shape, an expanded-metal shape, or the like as appropriate. The positive electrode current collector501preferably has a thickness of greater than or equal to 5 μm and less than or equal to 30 μm. The surface of the positive electrode current collector501may be provided with an undercoat using graphite or the like.

The positive electrode active material layer502may further include, in addition to a positive electrode active material, a binder for increasing adhesion of the positive electrode active material, a conductive additive for increasing the conductivity of the positive electrode active material layer502, and the like.

Examples of the positive electrode active material that can be used for the positive electrode active material layer502include a composite oxide with an olivine structure, a composite oxide with a layered rock-salt structure, and a composite oxide with a spinel structure. For example, a compound such as LiFeO2, LiCoO2, LiNiO2, LiMn2O4, V2O5, Cr2O5, or MnO2can be used as the positive electrode active material.

In particular, LiCoO2is preferable because it has high capacity and higher stability in the air and higher thermal stability than LiNiO2, for example.

It is preferable to add a small amount of lithium nickel oxide (LiNiO2or LiNi1-xMxO2(0<x<1) (M=Co, Al, or the like)) to a lithium-containing material with a spinel structure which contains manganese such as LiMn2O4because characteristics of the secondary battery using such a material can be improved.

Alternatively, a complex material (LiMPO4(general formula) (M is one or more of Fe(II), Mn(II), Co(II), and Ni(II))) can be used. Typical examples of the general formula LiMPO4which can be used as a material are lithium compounds such as LiFePO4, LiNiPO4, LiCoPO4, LiMnPO4, LiFeaNibPO4, LiFeaCobPO4, LiFeaMnbPO4, LiNiaCobPO4, LiNiaMnbPO4(a+b≤1, 0<a<1, and 0<b<1), LiFecNidCoePO4, LiFecNidMnePO4, LiNicCodMnePO4(c+d+e≤1, 0<c<1, 0<d<1, and 0<e<1), and LiFefNigCohMniPO4(f+g+h+i≤1, 0<f<1, 0<g<1, 0<h<1, and 0<i<1).

LiFePO4is particularly preferable because it meets requirements for the positive electrode active material in a balanced manner, such as safety, stability, high capacity density, and the existence of lithium ions that can be extracted in initial oxidation (charging).

Alternatively, a complex material such as Li(2-j)MSiO4(general formula) (M is one or more of Fe(II), Mn(II), Co(II), and Ni(II); 0≤j≤2) can be used. Typical examples of the general formula Li(2-j)MSiO4which can be used as a material are lithium compounds such as Li(2-j)FeSiO4, Li(2-j)NiSiO4, Li(2-j)CoSiO4, Li(2-j)MnSiO4, Li(2-j)FekNilSiO4, Li(2-j)FekColSiO4, Li(2-j)FekMnlSiO4, Li(2-j)NikColSiO4, Li(2-j)NikMnlSiO4(k+l≤1, 0<k<1, and 0<l<1), Li(2-j)FemNinCoqSiO4, Li(2-j)FemNinMnqSiO4, Li(2-j)NimConMnqSiO4(m+n+q≤1, 0<m<1, 0<n<1, and 0<q<1), and Li(2-j)FerNisCotMnuSiO4(r+s+t+u≤1, 0<r<1, 0<s<1, 0<t<1, and 0<u<1).

Still alternatively, a nasicon compound expressed by AxM2(XO4)3(general formula) (A=Li, Na, or Mg, M=Fe, Mn, Ti, V, or Nb, X=S, P, Mo, W, As, or Si) can be used for the positive electrode active material. Examples of the nasicon compound are Fe2(MnO4)3, Fe2(SO4)3, and Li3Fe2(PO4)3. Further alternatively, a compound expressed by Li2MPO4F, Li2MP2O7, or Li5MO4(general formula) (M=Fe or Mn), a perovskite fluoride such as NaFeF3and FeF3, a metal chalcogenide (a sulfide, a selenide, or a telluride) such as TiS2and MoS2, an oxide with an inverse spinel structure such as LiMVO4, a vanadium oxide (V2O5, V6O13, LiV3O8, or the like), a manganese oxide, an organic sulfur compound, or the like can be used as the positive electrode active material.

In the case where carrier ions are alkali metal ions other than lithium ions, or alkaline-earth metal ions, a material containing an alkali metal (e.g., sodium or potassium) or an alkaline-earth metal (e.g., calcium, strontium, barium, beryllium, or magnesium) instead of lithium may be used as the positive electrode active material. For example, the positive electrode active material may be a layered oxide containing sodium such as NaFeO2or Na2/3[Fe1/2Mn1/2]O2.

Further alternatively, any of the above materials may be combined to be used as the positive electrode active material. For example, a solid solution obtained by combining two or more of the above materials can be used as the positive electrode active material. For example, a solid solution of LiCo1/3Mn1/3Ni1/3O2and Li2MnO3can be used as the positive electrode active material.

Note that although not illustrated, a conductive material such as a carbon layer may be provided on a surface of the positive electrode active material layer502. With the conductive material such as the carbon layer, conductivity of the electrode can be increased. For example, the positive electrode active material layer502can be coated with the carbon layer by mixing a carbohydrate such as glucose at the time of baking the positive electrode active material.

The average particle diameter of the primary particle of the positive electrode active material layer502is preferably greater than or equal to 50 nm and less than or equal to 100 μm.

Examples of the conductive additive include acetylene black (AB), graphite (black lead) particles, carbon nanotubes, graphene, and fullerene.

A network for electron conduction can be formed in the positive electrode511by the conductive additive. The conductive additive also allows maintaining of a path for electric conduction between the particles of the positive electrode active material layer502. The addition of the conductive additive to the positive electrode active material layer502increases the electron conductivity of the positive electrode active material layer502.

As the binder, instead of polyvinylidene fluoride (PVDF) as a typical one, polyimide, polytetrafluoroethylene, polyvinyl chloride, ethylene-propylene-diene polymer, styrene-butadiene rubber, acrylonitrile-butadiene rubber, fluorine rubber, polyvinyl acetate, polymethyl methacrylate, polyethylene, nitrocellulose or the like can be used.

The content of the binder in the positive electrode active material layer502is preferably greater than or equal to 1 wt % and less than or equal to 10 wt %, further preferably greater than or equal to 2 wt % and less than or equal to 8 wt %, and still further preferably greater than or equal to 3 wt % and less than or equal to 5 wt %. The content of the conductive additive in the positive electrode active material layer502is preferably greater than or equal to 1 wt % and less than or equal to 10 wt %, and further preferably greater than or equal to 1 wt % and less than or equal to 5 wt %.

In the case where the positive electrode active material layer502is formed by a coating method, the positive electrode active material, the binder, and the conductive additive are mixed to form a positive electrode paste (slurry), and the positive electrode paste is applied to the positive electrode current collector501and dried.

(Negative Electrode)

The negative electrode515includes, for example, the negative electrode current collector505and the negative electrode active material layer506formed over the negative electrode current collector505. AlthoughFIGS.16A and16Billustrate the example of one negative electrode515including the negative electrode active material layer506on only one side of the negative electrode current collector505with a sheet shape (or a band-like shape) and one negative electrode515including the negative electrode active material layer506on each side of the negative electrode current collector505, one embodiment of the present invention is not limited thereto. Only the negative electrodes515each including the negative electrode active material layer506on only one side of the negative electrode current collector505may be used. In this case, the sides of the negative electrode current collectors505, each of which is not provided with the negative electrode active material layer506, are preferably placed to be in contact with each other because such arrangement can make friction between the contacting sides low to easily relieve stress generated when the secondary battery102is curved. Only the negative electrodes515each including the negative electrode active material layer506on each side of the negative electrode current collector505may be used. With the use of the negative electrode515including the negative electrode active material layer506on each side of the negative electrode current collector505allows the secondary battery102to have high capacity. In addition, the secondary battery102may include three or more negative electrodes515. An increase in the number of the negative electrodes515in the secondary battery102can increase the capacity of the secondary battery102.

The negative electrode current collector505can be formed using a material that has high conductivity and is not alloyed with a carrier ion of lithium or the like, such as stainless steel, gold, platinum, iron, copper, titanium, or an alloy thereof. Alternatively, an aluminum alloy to which an element which improves heat resistance, such as silicon, titanium, neodymium, scandium, or molybdenum, is added can be used. The negative electrode current collector505can have a foil-like shape, a plate-like shape (a sheet-like shape), a net-like shape, a punching-metal shape, an expanded-metal shape, or the like as appropriate. The negative electrode current collector505preferably has a thickness greater than or equal to 5 μm and less than or equal to 30 μm. The surface of the negative electrode current collector505may be provided with an undercoat using graphite or the like.

The negative electrode active material layer506may further include, in addition to a negative electrode active material, a binder for increasing adhesion of the negative electrode active material, a conductive additive for increasing the conductivity of the negative electrode active material layer506, and the like.

There is no particular limitation on the negative electrode active material as long as it is a material with which lithium can be dissolved and precipitated or a material into/from which lithium ions can be inserted and extracted. Other than a lithium metal or lithium titanate, a carbon-based material generally used in the field of power storage, an alloy-based material, or the like can also be used for the negative electrode active material layer506.

The lithium metal is preferable because of its low redox potential (−3.045 V lower than that of a standard hydrogen electrode) and high specific capacity per unit weight and per unit volume (3860 mAh/g and 2062 mAh/cm3).

Examples of the carbon-based material include graphite, graphitizing carbon (soft carbon), non-graphitizing carbon (hard carbon), a carbon nanotube, graphene, carbon black, and the like.

Examples of the graphite include artificial graphite such as meso-carbon microbeads (MCMB), coke-based artificial graphite, or pitch-based artificial graphite and natural graphite such as spherical natural graphite.

Graphite has a low potential substantially equal to that of a lithium metal (0.1 V to 0.3 V vs. Li/Li+) when lithium ions are inserted into the graphite (when a lithium-graphite intercalation compound is formed). For this reason, a lithium ion battery can have a high operating voltage. In addition, graphite is preferable because of its advantages such as relatively high capacity per unit volume, small volume expansion, low cost, and safety greater than that of a lithium metal.

For the negative electrode active material, an alloy-based material or an oxide which enables charge-discharge reaction by an alloying reaction and a dealloying reaction with lithium can be used. In the case where lithium ions are carrier ions, the alloy-based material is, for example, a material containing at least one of Mg, Ca, Al, Si, Ge, Sn, Pb, Sb, Bi, Ag, Au, Zn, Cd, Hg, In, and the like. Such elements have higher capacity than carbon. In particular, silicon has a significantly high theoretical capacity of 4200 mAh/g. For this reason, silicon is preferably used as the negative electrode active material. Examples of the alloy-based material using such elements include Mg2Si, Mg2Ge, Mg2Sn, SnS2, V2Sn3, FeSn2, CoSn2, Ni3Sn2, Cu6Sn5, Ag3Sn, Ag3Sb, Ni2MnSb, CeSb3, LaSn3, La3Co2Sn7, CoSb3, InSb, SbSn, and the like.

Alternatively, for the negative electrode active material, an oxide such as SiO, SnO, SnO2, titanium oxide (TiO2), lithium titanium oxide (Li4Ti5O12), lithium-graphite intercalation compound (LixC6), niobium oxide (Nb2O5), tungsten oxide (WO2), or molybdenum oxide (MoO2) can be used.

Still alternatively, for the negative electrode active material, Li(3-x)MxN (M is Co, Ni, or Cu) with a Li3N structure, which is a nitride containing lithium and a transition metal, can be used. For example, Li2.6Co0.4N3is preferable because of high charge and discharge capacity (900 mAh/g and 1890 mAh/cm3).

A nitride containing lithium and a transition metal is preferably used, in which case lithium ions are contained in the negative electrode active materials and thus the negative electrode active materials can be used in combination with a material for a positive electrode active material that does not contain lithium ions, such as V2O5or Cr3O8. Note that in the case of using a material containing lithium ions as a positive electrode active material, the nitride containing lithium and a transition metal can be used as the negative electrode active material by extracting the lithium ions contained in the positive electrode active material in advance.

Alternatively, a material which causes a conversion reaction can be used as the negative electrode active material. For example, a transition metal oxide with which an alloying reaction with lithium is not caused, such as cobalt oxide (CoO), nickel oxide (NiO), or iron oxide (FeO), may be used for the negative electrode active material. Other examples of the material which causes a conversion reaction include oxides such as Fe2O3, CuO, Cu2O, RuO2, and Cr2O3, sulfides such as CoS0.89, NiS, or CuS, nitrides such as Zn3N2, Cu3N, and Ge3N4, phosphides such as NiP2, FeP2, and CoP3, and fluorides such as FeF3and BiF3. Note that any of the fluorides can be used as a positive electrode active material because of its high electrode potential.

In the case where the negative electrode active material layer506is formed by a coating method, the negative electrode active material and the binder are mixed to form a negative electrode paste (slurry), and the negative electrode paste is applied to the negative electrode current collector505and dried. Note that a conductive additive may be added to the negative electrode paste.

Graphene may be formed on a surface of the negative electrode active material layer506. In the case of using silicon as the negative electrode active material, the volume of silicon is greatly changed due to occlusion and release of carrier ions in charge-discharge cycles. Therefore, adhesion between the negative electrode current collector505and the negative electrode active material layer506is decreased, resulting in degradation of battery characteristics caused by charge and discharge. Thus, graphene is preferably formed on a surface of the negative electrode active material layer506containing silicon because even when the volume of silicon is changed in charge-discharge cycles, decrease in the adhesion between the negative electrode current collector505and the negative electrode active material layer506can be inhibited, which makes it possible to reduce degradation of battery characteristics.

Alternatively, a coating film of an oxide or the like may be formed on the surface of the negative electrode active material layer506. A coating film formed by decomposition or the like of an electrolyte solution or the like in charging cannot release electric charges used at the formation, and therefore forms irreversible capacity. In contrast, the film of an oxide or the like provided on the surface of the negative electrode active material layer506in advance can reduce or prevent generation of irreversible capacity.

As the coating film coating the negative electrode active material layer506, an oxide film of any one of niobium, titanium, vanadium, tantalum, tungsten, zirconium, molybdenum, hafnium, chromium, aluminum, and silicon or an oxide film containing any one of these elements and lithium can be used. Such a coating film is denser than a conventional coating film formed on a surface of a negative electrode due to a decomposition product of an electrolyte solution.

For example, niobium oxide (Nb2O5) has a low electric conductivity of 10−9S/cm and a high insulating property. For this reason, a niobium oxide film inhibits electrochemical decomposition reaction between the negative electrode active material and the electrolyte solution. On the other hand, niobium oxide has a lithium diffusion coefficient of 10−9cm2/sec and high lithium ion conductivity. Therefore, niobium oxide can transmit lithium ions. Alternatively, silicon oxide or aluminum oxide may be used.

A sol-gel method can be used to coat the negative electrode active material layer506with the coating film, for example. The sol-gel method is a method for forming a thin film in such a manner that a solution of metal alkoxide, a metal salt, or the like is changed into a gel, which has lost its fluidity, by hydrolysis reaction and polycondensation reaction and the gel is baked. Since a thin film is formed from a liquid phase in the sol-gel method, raw materials can be mixed uniformly on the molecular scale. For this reason, by adding a negative electrode active material such as graphite to a raw material of the metal oxide film which is a solvent, the active material can be easily dispersed into the gel. In such a manner, the coating film can be formed on the surface of the negative electrode active material layer506. A decrease in the capacity of the power storage unit can be prevented by using the coating film.

(Separator)

As a material of the separator503, a porous insulator such as cellulose, polypropylene (PP), polyethylene (PE), polybutene, nylon, polyester, polysulfone, polyacrylonitrile, polyvinylidene fluoride, tetrafluoroethylene, or polyphenylene sulfide can be used. Alternatively, nonwoven fabric of a glass fiber or the like, or a diaphragm in which a glass fiber and a polymer fiber are mixed may be used.

(Electrolyte Solution)

As an electrolyte in the electrolyte solution504, a material having carrier ion mobility and containing lithium ions serving as carrier ions is used. Typical examples of the electrolyte are lithium salts such as LiPF6, LiClO4, LiAsF6, LiBF4, LiCF3SO3, Li(CF3SO2)2N, Li(C2F5SO2)2N, and Li(SO2F)2N. One of these electrolytes may be used alone, or two or more of them may be used in an appropriate combination and in an appropriate ratio.

As a solvent of the electrolyte solution504, a material having carrier ion mobility is used. As the solvent of the electrolyte solution, an aprotic organic solvent is preferably used. Typical examples of aprotic organic solvents include ethylene carbonate (EC), propylene carbonate, dimethyl carbonate, diethyl carbonate (DEC), ethylmethyl carbonate (EMC), γ-butyrolactone, acetonitrile, dimethoxyethane, tetrahydrofuran, and the like, and one or more of these materials can be used. When a gelled high-molecular material is used as the solvent of the electrolytic solution or a high-molecular material for gelling is added to the electrolytic solution, for example, safety against liquid leakage and the like is improved. Furthermore, the storage battery can be thinner and more lightweight. Typical examples of gelled high-molecular materials include a silicone gel, an acrylic gel, an acrylonitrile gel, a polyethylene oxide-based gel, a polypropylene oxide-based gel, a gel of a fluorine-based polymer, and the like. Alternatively, the use of one or more kinds of ionic liquids (room temperature molten salts) which have features of non-flammability and non-volatility as the solvent of the electrolyte solution can prevent the storage battery from exploding or catching fire even when the storage battery internally shorts out or the internal temperature increases owing to overcharging or the like. An ionic liquid is a salt in the fluid state and has high ion mobility (conductivity). An ionic liquid contains a cation and an anion. Examples of ionic liquids include an ionic liquid containing an ethylmethylimidazolium (EMI) cation and an ionic liquid containing an N-methyl-N-propylpiperidinium (PP13) cation.

(Exterior Body)

There are a variety of structures of a secondary battery, and a film is used for formation of the exterior body507in this embodiment. Note that the film used for the exterior body507is a single-layer film selected from a metal film (e.g., an aluminum film, a stainless steel film, and a nickel steel film), a plastic film made of an organic material, a hybrid material film including an organic material (e.g., an organic resin or fiber) and an inorganic material (e.g., ceramic), and a carbon-containing inorganic film (e.g., a carbon film or a graphite film); or a stacked-layer film including two or more of the above films. Forming depressions or projections on a surface of a metal film by embossing increases the surface area of the exterior body507exposed to outside air, achieving efficient heat dissipation.

In the case where the secondary battery102is changed in form by externally applying force, bending stress is externally applied to the exterior body507of the secondary battery102. This might partly deform or damage the exterior body507. Projections or depressions formed on the exterior body507can relieve a strain caused by stress applied to the exterior body507. Therefore, the secondary battery102can be more reliable. Note that a “strain” is the scale of change in form indicating the displacement of a point of an object relative to the reference (initial) length of the object. The exterior body507having depressions or projections can reduce the influence of a strain caused by application of external force to the power storage unit to an acceptable level. Thus, the power storage unit having high reliability can be provided.

The above is the description of the structure example.

Fabricating Method Example

An example of a fabricating method of the secondary battery102will be described below.

(Preparing Positive Electrode and Covering it with Separator)

First, the positive electrode511including the positive electrode active material layer502is placed on the separator503(seeFIG.17A).FIG.17Aillustrates an example where the positive electrode active material layer502is provided on each side of the positive electrode current collector501having a meandering shape in which slits are formed.

The slit formed in the positive electrode current collectors501can suppress the difference between the positions of end portions of the plurality of current collectors when the secondary battery102is curved. The slit can also relieve tension applied to the current collector far from the curvature center.

Furthermore, there is no positive electrode active material layer502in a region511a, which overlaps with a later-described slit of the negative electrode515when the positive electrode511and the negative electrode515are stacked in a later step. If the positive electrode active material layer502is present in the region511a, which overlaps with the slit of the negative electrode515, there is no negative electrode active material layer506over and below the positive electrode active material layer502in the region511a, which might cause a problem in a battery reaction. Specifically, this might concentrate carrier ions released from the positive electrode active material layer502in the negative electrode active material layer506in the region closest to the slit, so that the carrier ions might be deposited on the negative electrode active material layer506. Thus, the deposition of the carrier ions on the negative electrode active material layer506can be suppressed when there is no positive electrode active material layer502in the region511a, which overlaps with the slit of the negative electrode515.

Then, the separator503is folded along the dotted line inFIG.17Aso that the positive electrode511is interposed between facing parts of the separator503. Next, the outer edges of the separator503, which is outside of the positive electrode511, are bonded to form the bag-like separator503(seeFIG.17B). The bonding of the outer edges of the separator503can be performed with the use of an adhesive or the like, by ultrasonic welding, or by thermal fusion bonding.

In this embodiment, polypropylene is used as the separator503, and the outer edges of the separator503are bonded to each other by heating. Bonding portions503aare illustrated inFIG.17B. In such a manner, the positive electrode511can be covered with the separator503. The separator503is formed so as to cover the positive electrode active material layer502and does not necessarily cover the whole positive electrode511.

Note that althoughFIGS.17A and17Billustrate the example in which the separator503is folded, one embodiment of the present invention is not limited thereto. For example, the positive electrode511may be interposed between two separators. In that case, the bonding portion503amay be formed to surround almost all of the four sides of the positive electrode511.

The outer edges of the separator503may be bonded intermittently or may be bonded at dot-like bonding portions provided at regular intervals.

Alternatively, bonding may be performed along only one side of the outer edges. Alternatively, bonding may be performed along only two sides of the outer edges. Alternatively, bonding may be performed along four sides of the outer edges; accordingly, the four sides can be in an even state.

Note that although the case where the positive electrode511is covered with the separator503is shown inFIGS.17A and17Band the like, one embodiment of the present invention is not limited thereto. The positive electrode511is not necessarily covered with the separator503, for example. The negative electrode515, instead of the positive electrode511, may be covered with the separator503, for example.

(Preparing Negative Electrode)

Next, the negative electrode515is prepared (seeFIG.17C).FIG.17Cillustrates an example where the negative electrode active material layer506is provided on each side of the negative electrode current collector505having a meandering shape in which slits are formed.

The slit formed in the negative electrode current collectors505can suppress the difference between the positions of end portions of the plurality of current collectors when the secondary battery102is curved. The slit can also relieve tension applied to the current collector far from the curvature center.

(Making Positive Electrodes and Negative Electrodes Overlap With Each Other and Connecting Leads)

Next, the positive electrodes511and the negative electrodes515are stacked (seeFIG.18A). This embodiment shows an example in which two positive electrodes511and two negative electrodes515are used.

Next, the positive electrode lead521including a sealing layer520is electrically connected to positive electrode tabs of the plurality of positive electrode current collectors501by ultrasonic wave irradiation with pressure applied (ultrasonic welding).

The lead is likely to be cracked or cut by stress due to external force applied after fabrication of the power storage unit.

When subjected to ultrasonic welding, the positive electrode lead521are placed between bonding dies provided with projections, whereby a connection region and a curved portion can be formed in the positive electrode tab (FIG.18B).

This curved portion can relieve stress due to external force applied after fabrication of the secondary battery102. Therefore, the secondary battery102can be more reliable.

The curved portion is not necessarily formed in the positive electrode tab. The positive electrode current collector may be formed using a high-strength material such as stainless steel to a thickness of 10 μm or less, in order to easily relieve stress due to external force applied after fabrication of a secondary battery.

It is needless to say that two or more of the above examples may be combined to relieve concentration of stress in the positive electrode tab.

Then, in a manner similar to that of the positive electrode current collector501, the negative electrode lead525including the sealing layer520is electrically connected to the negative electrode tab of the negative electrode current collector505by ultrasonic welding.

(Preparing Exterior Body and Covering Positive Electrodes and Negative Electrodes)

A film used as an exterior body is folded, and thermocompression bonding is performed along one side of the folded exterior body. A portion where thermocompression bonding is performed along one side of the folded exterior body507is shown as a bonding portion507ainFIG.18B. With the exterior body507thus obtained, the positive electrodes511and the negative electrodes515are covered.

(Injecting Electrolyte Solution)

Next, thermocompression bonding is also performed in a manner similar to the above along one side of the exterior body507, which overlaps with the sealing layer520provided on the positive electrode lead521and the sealing layer520provided on the negative electrode lead525(FIG.19A). After that, the electrolyte solution504is injected from an unsealed side507bof the exterior body507, which is illustrated inFIG.19A, into a region covered with the exterior body507.

Then, the remaining open side of the exterior body507is sealed under vacuum, heating, and pressing, whereby the secondary battery102can be formed (FIG.19B). Injecting the electrolyte solution and sealing are performed in an environment from which oxygen is eliminated, for example, in a glove box. The evacuation to a vacuum is preferably performed with a vacuum sealer, a liquid pouring sealer, or the like. Heating and pressing can be performed for the unsealed side507bplaced between two heatable bars included in the sealer. An example of the conditions is as follows: the degree of vacuum is 60 kPa, the heating temperature is 190° C., the pressure is 0.1 MPa, and the time is 3 seconds. Here, sealing may be performed while the exterior body507is held down on its upper side. Thus, bubbles which enter between the positive electrode and the negative electrode when the electrolyte solution is injected can be removed.

Modification Example

FIG.20Aillustrates a modification example of the secondary battery102. The secondary battery102illustrated inFIG.20Ais different from the secondary battery102shown inFIG.15in the arrangement of the positive electrode lead521and the negative electrode lead525. Specifically, the positive electrode lead521and the negative electrode lead525in the secondary battery102inFIG.15are provided on the same side of the exterior body507, whereas the positive electrode lead521and the negative electrode lead525in the secondary battery102inFIGS.20A and20Bare provided on different sides of the exterior body507. Thus, the leads of the secondary battery of one embodiment of the present invention can be freely positioned, and accordingly the degree of freedom in design is high. Accordingly, a product including the secondary battery of one embodiment of the present invention can have a higher degree of freedom in design. Furthermore, the yield of products each including the secondary battery of one embodiment of the present invention can be increased.

FIG.20Billustrates a fabrication process of the secondary battery102inFIG.20A. The fabricating method of the secondary battery102inFIG.15can be referred to for the details. Note that inFIG.20B, the electrolyte solution504is not illustrated.

Pressing (e.g., embossing) may be performed to form unevenness in advance on a surface of a film used as the exterior body507. The unevenness on the surface of the film increases flexibility of a secondary battery and further relieves stress. The depressions or projections of a surface (or a rear surface) of the film formed by embossing form an obstructed space that is sealed by the film serving as a part of a wall of the sealing structure and whose inner volume is variable. It can be said that the depressions or projections of the film form an accordion structure (bellows structure) in this obstructed space. Note that embossing, which is a kind of pressing, is not necessarily employed and any method that allows formation of a relief on part of the film is employed.

Note that one embodiment of the present invention is not limited thereto. Various embodiments of the invention are described in this embodiment and the other embodiment, and one embodiment of the present invention is not limited to a particular embodiment. For example, although an example of use of one embodiment of the present invention in a lithium-ion secondary battery is described, one embodiment of the present invention is not limited thereto. One embodiment of the present invention can be used for a variety of secondary batteries, a lead storage battery, a lithium-ion polymer secondary battery, a nickel-hydrogen storage battery, a nickel-cadmium storage battery, a nickel-iron storage battery, a nickel-zinc storage battery, a silver oxide-zinc storage battery, a solid-state battery, an air battery, a primary battery, a capacitor or a lithium ion capacitor, and the like. One embodiment of the present invention is not necessarily used for a lithium-ion secondary battery.

The above is the description of the fabricating method example.

At least part of this embodiment can be implemented in combination with any of the other embodiment described in this specification as appropriate.

EXPLANATION OF REFERENCE

10: connecting member,11: pipe,11a: partition wall,11b: portion,11c: portion,12: pivot,12a: tip portion,12b: collar portion,12c: axis portion,12d: end portion,13: spring,13a: spring,13b: spring,14: cushioning material,15: cushioning material,20: power supply device,20a: power supply device,20b: power supply device,21: exterior body,21a: exterior body,21b: exterior body,21c: exterior body,21d: exterior body,22: battery,23: tab,24: wiring,25: conductive member,26: exterior body,27: content,28: protective circuit,29: substrate,30: electronic device,31: housing,32: display portion,33: lug,34: bearing,35: switch,41: battery,42: tab,42a: electrode,42b: electrode,50: system,51: buckle,52: hole,61: control portion,62: power control portion,63: functional circuit,64: sensor,65: battery,66: power receiving portion,68: power supply line,69: bus line,71: terminal,72: wiring,73a: cushioning portion,73b: cushioning material,75: substrate,76a: FPC,76b: FPC,102: secondary battery,300: head-mounted display,301: housing,302: display portion,303: operation button,305: lens,306: dial,310: mobile information terminal,311: housing,312: display portion,313: operation button,314: external connection port,315: speaker,316: microphone,317: camera,320: camera,321: housing,322: display portion,323: operation button,324: shutter button,326: lens,501: positive electrode current collector,502: positive electrode active material layer,503: separator,503a: bonding portion,504: electrolyte solution,505: negative electrode current collector,506: negative electrode active material layer,507: exterior body,507a: bonding portion,507b: side,511: positive electrode,511a: region,515: negative electrode,520: sealing layer,521: positive electrode lead,525: negative electrode lead

This application is based on Japanese Patent Application serial No. 2016-035810 filed with Japan Patent Office on Feb. 26, 2016, the entire contents of which are hereby incorporated by reference.