BATTERY MODULE AND CAPSULE ENDOSCOPE INCLUDING THE SAME

A battery module including: a first battery; a second battery; a connection plate wholly disposed between the first and second batteries. Where the connection plate has: a first portion electrically connected to a first metal electrode of the first battery, the first metal electrode having a first polarity; a second portion electrically connected to a second metal electrode of the second battery, the second metal electrode having an opposite polarity than the first polarity; and a connecting portion connecting the first and second portions through one or more folded portions.

BACKGROUND OF INVENTION

1. Field of the Invention

The present invention relates to a battery module including a plurality of batteries and a connection body which connects in series the plurality of batteries and a capsule endoscope including the battery module.

2. Description of the Related Art

A battery module having a plurality of cells connected directly is well-known and is disclosed in, for example, Japanese Patent Application Laid-Open Publication No. 10-106533.

Japanese Patent Application Laid-Open Publication No. 10-106533 discloses a configuration which uses a connection body to connect two cells for forming a battery module which obtains a required outputted voltage by directly connecting the individual cells.

FIG. 7shows a partial cross-sectional view showing a configuration of a conventional battery module. More specifically, as shown inFIG. 7, Japanese Patent Application Laid-Open Publication No. 10-106533 discloses a configuration of a battery module in which respective outer surfaces of batteries A and B of a same type and a same standard and in the form of a circular column are covered with a metal sheath102doubling as a negative electrode, except for respective one end faces (the one end face of the battery B is not shown). In the configuration, a metal electrode103which is insulated from the metal sheath102is provided as a positive electrode at each one end face of the batteries A and B (the metal electrode103of the battery B is not shown), and the metal electrode103of the battery A and the metal sheath102of the battery B are electrically connected by a connection body101to bring the batteries A and B connected in series.

Note that a connection portion101bof the connection body101for the battery B is shaped to fit with the battery B and that the connection portion101bis welded to an outer circumferential side of the metal sheath102of the battery B after the battery B is fitted with the connection portion101b.

A connection portion101aof the connection body101for the battery A is welded to the metal electrode103of the battery A. With the configuration, the connection body101electrically connects the batteries A and B.

SUMMARY OF THE INVENTION

In order to attain the above-described object, a battery module according to one aspect of the present invention is a battery module including a plurality of batteries formed to have a same diameter and a connection body between the plurality of batteries which electrically connects in series a metal electrode of one polarity of one of the batteries with a metal electrode of the other polarity of another battery, wherein the connection body includes a first connection portion which is electrically connected to the metal electrode of the one battery and a second connection portion which is electrically connected to the metal electrode of the other battery and is arranged in a region which overlaps with the individual batteries when the individual batteries connected by the connection body are viewed in a plan view from one of two sides in a direction of series connection of the individual batteries.

A capsule endoscope including a battery module according to one aspect of the present invention includes the battery module according to claim1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the drawings are schematic and that a relationship between thickness and width of each member, a ratio among respective thicknesses of members, and the like are different from actual ones. The drawings, of course, include portions having different dimensional relationships and ratios.

First Embodiment

FIG. 1is a view schematically showing a configuration of a battery module illustrating the present embodiment, andFIG. 2is a top view of the battery module inFIG. 1as viewed from direction II inFIG. 1.

As shown inFIG. 1, a main portion of a battery module100is composed of a button battery1as one battery, a button battery2as the other battery, a connection body3, and a reinforcing agent4.

The button battery1has a metal electrode1a of positive electrode as the other polarity formed at one surface and a metal electrode1bof negative electrode as one polarity formed at the other surface, in a direction S of series connection to the button battery2.

The button battery2is of a same standard and a same type as the button battery1, i.e., is formed to have a same diameter in a radial direction R. The button battery2has a metal electrode2aof positive electrode as the other polarity formed at one surface in the direction S of series connection and a metal electrode2bof negative electrode as one polarity formed at the other surface. That is, the metal electrode2ais located so as to face the metal electrode1b.

The connection body3is composed of a plate-like member which has a thickness v and is made of, e.g., aluminum and electrically connects in series the metal electrode1bof the button battery1with the metal electrode2aof the button battery2.

That is, the button battery1and button battery2are formed integrally with each other by the connection body3. In other words, the button batteries1and2are integrated together by the connection body3. Note that the button batteries1and2do not separate after the integration by the connection body3.

The connection body3causes positions in the radial direction R of the button batteries1and2formed to have the same diameter to coincide with each other to thereby integrate the button batteries1and2together.

More specifically, the button batteries1and2are integrated together such that the button battery1overlaps completely with the button battery2when the battery module100is viewed in a plan view from either the metal electrode1aof the button battery1or the metal electrode2bof the button battery2in the direction S of series connection.

The connection body3includes a first connection portion3bwhich is electrically connected to the metal electrode1band a second connection portion3awhich is electrically connected to the metal electrode2a. The connection body3also has two folded portions3cfolded between the first connection portion3band the second connection portion3a, i.e., is formed by folding the plate-like member twice and has a Z-folded shape in cross section between the button batteries1and2.

As shown inFIGS. 1 and 2, the connection body3is arranged between the metal electrode1bof the button battery1and the metal electrode2aof the button battery2and is arranged in a region Q which overlaps with the individual batteries1and2when the battery module100is viewed in a plan view from, e.g., the metal electrode2bof the button battery2in the direction S of series connection. That is, the connection body3is not arranged such that a portion of the connection body3protrudes in the radial direction R from outer circumferences of the button batteries1and2.

The reinforcing agent4is composed of, e.g., epoxy resin, and the region Q is filled with the reinforcing agent4. The reinforcing agent4has a function of reinforcing connection of the first connection portion3bto the metal electrode1band connection of the second connection portion3ato the metal electrode2a.

Note that only the region Q is filled with the reinforcing agent4and that the reinforcing agent4does not protrude in the radial direction R from the outer circumferences of the button batteries1and2. The reinforcing agent is not limited to epoxy resin and may be composed of acrylic resin, phenol resin, polyurethane resin, or the like.

A method for manufacturing the above-described battery module100will be described with reference toFIGS. 3A to 3D.FIG. 3Ais a view schematically showing a state in which a plate-like member is set in a die in a process showing the method for manufacturing the battery module inFIG. 1.FIG. 3Bis a view schematically showing a state in which a second connection portion of the plate-like member inFIG. 3Adeformed by the die is electrically connected to a metal electrode of the other button battery in the process showing the method for manufacturing the battery module inFIG. 1.

FIG. 3Cis a view schematically showing a state in which a first connection portion of the plate-like member inFIG. 3Bdeformed by the die is electrically connected to a metal electrode of one button battery in the process showing the method for manufacturing the battery module inFIG. 1.FIG. 3Dis a view schematically showing a state in which the other button battery inFIG. 3Cis moved until the other button battery faces the one button battery in the process showing the method for manufacturing the battery module inFIG. 1.

To manufacture the battery module100, a plate-like member6made of, e.g., aluminum is first set in a die5, as shown inFIG. 3A. After the setting, the plate-like member6is cranked using the die5so as to have two 90° folded portions. As a result, the plate-like member6forms the connection body3.

As shown inFIG. 3B, the second connection portion3aof the connection body3is joined to the metal electrode2aof the button battery2by, e.g., a known ultrasound joining method. As a result, the second connection portion3ais electrically connected to the metal electrode2a.

Note that ultrasound joining is used to join the electrode and connection portion because ultrasound joining does not use heat and does not apply heat to the button battery2at the time of the joining. For the reason, if exposure of a battery or the like to high temperatures does not matter, spot welding may be used. Alternatively, a method using a conductive adhesive, a conductive adhesive tape, or the like may be utilized.

As shown inFIG. 3C, after the connection body3electrically connected to the button battery2and metal electrode2ais inverted 180° in the direction S of series connection, the first connection portion3bof the connection body3is joined to the metal electrode1bof the button battery1by, e.g., ultrasound joining.

Note that the joining of the first connection portion3bto the metal electrode1bmay be performed without inverting the connection body3electrically connected to the button battery2and metal electrode2a180° in the direction S of series connection. A reason for the use of ultrasound joining for the joining is as described above. Thus, spot welding, a method using a conductive adhesive or a conductive adhesive tape, or the like may also be utilized to join the electrode and connection portion. As a result, the first connection portion3bis electrically connected to the metal electrode1b, and the button batteries1and2are integrated together by the connection body3.

As shown inFIG. 3D, the button battery2is moved in the radial direction R to a position where the button battery2faces the button battery1in the direction S of series connection while the button battery1is fixed, and the connection body3is folded in a Z-shape.

When the button battery2is pressed against the button battery1after the folding, the connection body3is compressively deformed in the direction S of series connection while remaining Z-shaped to have a shape shown inFIG. 1. Finally, the region Q is filled with the reinforcing agent4. The battery module100is manufactured in the above-described manner.

As described above, the present embodiment has described that the connection body3is arranged between the metal electrode1bof the button battery1and the metal electrode2aof the button battery2and that the connection body3is arranged in the region Q overlapping with the button batteries1and2when the battery module100is viewed in a plan view from, e.g., the metal electrode2bof the button battery2in the direction S of series connection.

With the above-described configuration, a portion of the connection body is prevented from protruding outward in the radial direction R from the outer circumferences of the button batteries1and2as in a conventional battery module. An outer diameter of the battery module100is equal to outer diameters of the button batteries1and2.

Thus, the battery module100including a configuration which allows achievement of reduction in diameter in the radial direction R of the battery module100to achieve size reduction can be provided.

Second Embodiment

FIG. 4is a view schematically showing a configuration of a battery module illustrating the present embodiment.

The configuration of the battery module according to the second embodiment is different from the above-described battery module100according to the first embodiment shown inFIGS. 1 and 2in that the number of folded portions3cwhich are formed in a connection body3is larger than the number of folded portions3cin the first embodiment. Accordingly, only the difference will be described, same components as in the first embodiment are denoted by same reference numerals, and a description of the components will be omitted.

As shown inFIG. 4, the connection body3′ in a battery module100′ according to the present embodiment has a plurality of (e.g., five inFIG. 4) folded portions3calong a direction S of series connection between a first connection portion3band a second connection portion3a. The connection body3′ is formed by being mountain-folded a plurality of times and being valley-folded a plurality of times between a button battery1and a button battery2. Note that the number of folded portions3cis not limited to five.

A distance between the button batteries1and2in the direction S of series connection increases each time the number of folded portions3cincreases by one and decreases each time the number of folded portions3cdecreases by one. The distance between the button batteries1and2in the direction S of series connection increases with increase in an angle constituting an acute angle of each folded portion3cin a cross section inFIG. 4, i.e., a folded angle and decreases with decrease in the folded angle.

That is, a distance L between the button batteries1and2in the direction S of series connection can be freely set according to the number of folded portions3cof the connection body3and/or folded angles.

As shown inFIG. 4, the connection body3′ is arranged between a metal electrode1bof the button battery1and a metal electrode2aof the button battery2and is arranged in a region which overlaps with the individual batteries1and2when the battery module100′ is viewed in a plan view from, e.g., a metal electrode2bof the button battery2in the direction S of series connection, like the above-described first embodiment.

Note that remaining components of the battery module100′ are same as the corresponding components of the battery module100according to the above-described first embodiment and that a description of the components will be omitted.

A method for manufacturing the above-described battery module100′ will be described with reference toFIGS. 5A to 5C.FIG. 5Ais a view schematically showing a state in which a plate-like member is set in a die in a process showing the method for manufacturing the battery module inFIG. 4.FIG. 5Bis a view schematically showing a state in which a first connection portion of the plate-like member inFIG. 5Adeformed by the die is electrically connected to a metal electrode of one button battery and a second connection portion is electrically connected to a metal electrode of the other button battery in the process showing the method for manufacturing the battery module inFIG. 4.FIG. 5Cis a view schematically showing a state in which the other button battery inFIG. 5Bis moved until the other button battery faces the one button battery in the process showing the method for manufacturing the battery module inFIG. 4.

To manufacture the battery module100, a plate-like member6made of, e.g., aluminum is first set in a die5, as shown inFIG. 5A. After the setting, the plate-like member6is mountain-folded and valley-folded using the die5to have a plurality of (e.g., five) folded portions3c. As a result, the plate-like member6forms the connection body3.

As shown inFIG. 5B, in a state in which the button battery1and button battery2are placed so as to be coplanar with each other, the second connection portion3aof the connection body3′ is joined to the metal electrode2aof the button battery2by, e.g., ultrasound joining, and the first connection portion3bof the connection body3′ is joined to the metal electrode1bof the button battery1by, e.g., ultrasound joining.

Note that the button batteries1and2are placed so as to be coplanar with each other because the joining of the second connection portion3ato the metal electrode2aand the joining of the first connection portion3bto the metal electrode1bthat are performed together facilitate joining work to allow improvement in workability.

The joining of the electrodes and connection portions inFIG. 5Bmay be performed by utilizing spot welding, a method using a conductive adhesive or a conductive adhesive tape, or the like, as in the above-described first embodiment.

As a result of the joining inFIG. 5B, the second connection portion3ais electrically connected to the metal electrode2a, and the first connection portion3bis electrically connected to the metal electrode1b. That is, the button battery1is integrated with the button battery2by the connection body3.

As shown inFIG. 5C, the button battery2is rotationally moved 180° to a position where the button battery2faces the button battery1in the direction S of series connection while the button battery1is fixed. More specifically, the button battery2is rotationally moved to a position where the metal electrode2afaces the metal electrode1b.

After the rotational movement, the button battery2is pressed against the button battery1, and the connection body3is compressively deformed in the direction S of series connection. Finally, a region Q is filled with a reinforcing agent4. The battery module100′ shown inFIG. 4is manufactured in the above-described manner

As described above, in the present embodiment, the number of folded portions3cof the connection body3′ is larger than the number of folded portions3cof the connection body3according to the first embodiment.

With the above-described configuration, the distance L in the direction S of series connection of the button battery2from the button battery1can be freely set according to the number of folded portions3cof the connection body3′ and/or folded angles.

Thus, size of the battery module100′ can be adjusted to a length suited to a storage space for a power supply portion of electronic equipment in which the battery module100′ is to be installed. Note that other effects are same as in the above-described first embodiment.

Note that the battery module100in the first embodiment and the battery module100′ in the second embodiment described above are each provided in electronic equipment such as a capsule endoscope.

A configuration of a capsule endoscope in which the battery module inFIG. 1 or 4is provided will be briefly described below with reference toFIG. 6.FIG. 6is a cross-sectional view showing an outline of the configuration of the capsule endoscope in which the battery module inFIG. 1 or 4is provided.

As shown inFIG. 6, a capsule endoscope50is in the form of a capsule type tablet in appearance. The capsule endoscope50has a housing50kwhich is in the form of a capsule substantially elliptical in vertical cross section and is made of, e.g., resin. A front portion of the housing50kis formed of a transparent member.

Inside the housing50k, lenses51for observing an interior of a body cavity, a light source52which illuminates the interior of the body cavity and is made up of, e.g., an LED, a solid image pickup device53which subjects light incidence to a light-receiving surface via the lenses51to predetermined photoelectric conversion processing and outputs an image signal and is made up of, e.g., a CCD or CMOS sensor, a peripheral circuit board54which has peripheral circuits such as a driver circuit which controls driving of the image pickup device53, a communication circuit which transfers and outputs a picked-up image signal to outside the body cavity, and a control circuit which controls driving of the entire capsule endoscope50and is made up of, e.g., a rigid board, and the above-described battery module100(100′) are provided.

Note that the capsule endoscope50is configured such that electrical power is supplied from the battery module100(100′) to the light source52, solid image pickup device53, and peripheral circuit board54via a flexible board (not shown) which is provided in the capsule endoscope50when the flexible board or the like is electrically connected to the metal electrode1aof the button battery1and the metal electrode2bof the button battery2.

The battery module100(100′) is provided in the capsule endoscope50such that a radial direction R coincides with a short axis direction of the capsule endoscope50.

As described above, since the connection body3(3′) is arranged between the button batteries1and2so as not to protrude from the outer circumferences of the individual button batteries1and2, the battery module100(100′) has a diameter reduced in the radial direction R.

An inner diameter in the short axis direction of the capsule endoscope50can thus be made to coincide with the diameters in the radial direction R of the individual button batteries1and2, which can achieve reduction in size of the capsule endoscope50.

Since the connection body3(3′) does not protrude from the outer circumferences of the individual button batteries1and2, the battery module100(100′) can be easily incorporated into the capsule endoscope50.

A reason for the easy incorporation is that a portion of the connection body3(3′) does not protrude to come into contact with a different part in the capsule endoscope50. The configuration not only improves workability but also eliminates a need to take into account insulation of the protruding connection body3.

A configuration in which a plurality of batteries are electrically connected to one another by pressing the batteries against one another using a strong spring or the like is generally used to incorporate a battery module into electronic equipment such as a capsule endoscope. According to the configurations of the battery modules100and100of the first and second embodiments described above, electrical connection between batteries can be ensured even with a small force against the batteries. In addition, a plurality of batteries need not be incorporated one by one when the batteries are incorporated into electronic equipment such as a capsule endoscope, and the batteries can be easily incorporated, which improves workability.

Thus, the battery module100(100′) including a configuration which allows achievement of reduction in diameter to achieve size reduction and the capsule endoscope50including the battery module100(100′) can be provided.

Note that modifications will be described below. The above-described first and second embodiments have illustrated cases where the connection body3is composed of a plate-like member. The connection body3may, of course, be composed of a linear member.

Although use of aluminum (Al) as a material for the plate-like member has been illustrated, it will be appreciated that the material for the plate-like member may be a metal having high electric conductivity, such as copper (Cu) or gold (Au), or a clad material using a metal having high electric conductivity.

Use of button batteries as the one button battery1and the other button battery2has been illustrated. The batteries are not limited to primary batteries such as an alkaline dry battery and a manganese dry battery and may, of course, be secondary batteries such as a lithium ion battery, a nickel-cadmium battery, and a nickel hydrogen battery.

It will be appreciated that the number of batteries is not limited to two. The number may, of course, be three or more.

Although cases where the battery module100or100is provided in the capsule endoscope50have been illustrated, the present invention is not limited thereto. The present invention may, of course, be applied to a case where the battery module100or100′ is provided in different electronic equipment.

The above-described embodiments include inventions in various stages, and various inventions can be extracted by appropriately combining the plurality of constituent features disclosed. For example, even in a case where some constituent features are removed from all the constituent features described in the above-described one embodiment, if the problems described in Problems to be Solved by the Invention can be solved, and effects described as effects of the invention can be obtained, a configuration from which the constituent features have been removed can be extracted as an invention.