METAL-SHELL BATTERY AND ELECTRONIC DEVICE

A metal-shell battery includes: a cell including a metal housing and an electrode assembly sealed in the metal housing; a first conductive sheet; and a second conductive sheet. The metal housing includes a first surface. An electrode post is disposed protrusively on the first surface and is insulated from the metal housing. Two electrodes of the electrode assembly are electrically connected to the electrode post and the metal housing respectively. One end of the first conductive sheet is connected to the first surface. One end of the second conductive sheet is connected to the electrode post. A circuit board is connected to the other end of the first conductive sheet and the other end of the second conductive sheet respectively. |S1-S2|≤1 mm, S1 and S2 are distances between the first surface, and the one end and the other end of the circuit board respectively.

CROSS REFERENCE TO THE RELATED APPLICATION

The present application claims the priority of Chinese Patent Application No. 202120535992.3, filed on Mar. 15, 2021, the entire content of which is incorporated herein by reference.

TECHNICAL FIELD

This application relates to the technical field of batteries, and in particular, to a metal-shell battery and an electronic device.

BACKGROUND

With the rapid development of science and technology, more and more electronic products are emerging. To meet mobility requirements of users in diverse scenarios, the electronic products are increasingly smaller in size and weight but are increasingly powerful in functionality. Therefore, harsher requirements are posed on a battery that serves as a power source of the electronic products. Currently, a battery that uses a nickel-plated steel shell as an outer shell is applied more widely by good features such as high rigidity, resistance to pressure, and resistance to deformation.

It is found that, in the metal-shell battery, a circuit board is usually fitted snugly to the two electrodes of the metal-shell battery to minimize a distance between the circuit board and the two electrodes of the metal-shell battery. However, a distance between one electrode of the metal-shell battery and the circuit board is different from a distance between the other electrode and the circuit board. Consequently, the circuit board is disposed obliquely against the metal housing and therefore occupies more installation space, thereby being detrimental to miniaturization and lightweight design of the metal-shell battery.

SUMMARY

Embodiments of this application provide a metal-shell battery and an electronic device to reduce installation space occupied by a circuit board, and in turn, reduce space occupied by the metal-shell battery, so as to meet miniaturization and lightweight requirements of the metal-shell battery.

To solve the foregoing technical problem, a technical solution adopted by the embodiments of this application is: a metal-shell battery is provided, where the metal-shell battery includes a cell. The cell includes a metal housing and an electrode assembly sealed in the metal housing. The metal housing includes a first surface. An electrode post is disposed protrusively on the first surface. The electrode post is insulated from the metal housing. Two electrodes of the electrode assembly are electrically connected to the electrode post and the metal housing respectively. The metal-shell battery further includes: a first conductive sheet, where one end of the first conductive sheet is connected to the first surface; a second conductive sheet, where one end of the second conductive sheet is connected to the electrode post; and a circuit board, connected to the other end of the first conductive sheet and the other end of the second conductive sheet respectively. A distance between one end of the circuit board along a length direction of the circuit board and the first surface is a first spacing S1, a distance between the other end of the circuit board along the length direction of the circuit board and the first surface is a second spacing S2, and S1 and S2 satisfy: |S1-S2|≤1 mm.

Optionally, the circuit board includes a first plane. The other end of the first conductive sheet and the other end of the second conductive sheet are both connected to the first plane.

Optionally, the first plane is disposed at an angle to the first surface, and the angle α1 between the first plane and the first surface satisfies 0°≤α1≤30°.

Optionally, the first plane is disposed at an angle to the first surface, and the angle α2 between the first plane and the first surface satisfies 80°≤α2≤100°.

Optionally, the metal-shell battery further includes an insulation filler. The insulation filler is disposed between the first surface and the circuit board.

Optionally, the metal-shell battery further includes a pantograph strip. The pantograph strip is disposed on the first surface. One end of the first conductive sheet is connected to the first surface by the pantograph strip.

Optionally, the metal-shell battery further includes a protection piece. The protection piece is disposed on the first surface. The protection piece at least partly overlays the circuit board.

Optionally, the protection piece is formed by a potting process, an adhesive dispensing process, or a low-pressure injection molding process.

Optionally, the circuit board further includes a circuit board body and an output terminal, one end of the output terminal is connected to the circuit board body, and the other end of the output terminal protrudes from the protection piece.

To solve the foregoing technical problem, another technical solution adopted by the embodiments of this application is: an electronic device is provided, where the electronic device includes the metal-shell battery described above.

Beneficial effects of the embodiments of this application are: The metal-shell battery and the electronic device according to the embodiments of this application controls the spacing between the circuit board and the first surface of the metal housing, so that the circuit board is approximately parallel to the first surface, thereby making it convenient to affix insulation tape outside a protection circuit module or perform low-pressure injection molding on the protection circuit module to form a protective body. In addition, the installation space occupied by the circuit board is reduced, and in turn, the space occupied by the metal-shell battery is reduced, thereby meeting miniaturization and lightweight requirements of the metal-shell battery.

DETAILED DESCRIPTION

For ease of understanding this application, the following describes this application in more detail with reference to drawings and specific embodiments. It needs to be noted that an element referred to herein as being “fixed to” or “fastened to” another element may directly exist on the other element, or may be fixed or fastened to the other element through one or more intermediate elements. An element referred to herein as “connected to” another element may be connected to the other element directly or through one or more intermediate elements. The terms “vertical”, “horizontal”, “left”, “right”, “in”, “out” and other similar expressions used herein are merely for ease of description.

Unless otherwise defined, all technical and scientific terms used herein have the same meanings as what is generally understood by a person skilled in the technical field of this application. The terms used in the specification of this application are merely intended to describe specific embodiments but not to limit this application. The term “and/or” used herein is intended to include any and all combinations of one or more related items preceding and following the term.

In addition, the technical features described below and mentioned in different embodiments of this application may be combined with each other so long as they do not conflict with each other.

Refer toFIG. 1andFIG. 2together, which show a metal-shell battery according to a first embodiment of this application. The metal-shell battery includes a cell10, a first conductive sheet20, a second conductive sheet30, and a circuit board40. The cell10includes a metal housing110and an electrode assembly120sealed in the metal housing110. One electrode of the electrode assembly120is connected to the metal housing110. The other electrode of the electrode assembly120protrudes from a surface of the metal housing110. In addition, the other electrode of the electrode assembly120is insulated from one electrode of the electrode assembly120. One end of the first conductive sheet20is connected to the surface of the metal housing110. The other end of the first conductive sheet20is connected to the circuit board40. One end of the second conductive sheet30is connected to the other electrode of the cell20. The other end of the second conductive sheet30is connected to the circuit board40.

For ease of description, in this embodiment of this application, one electrode of the cell20is defined as a positive electrode of the cell20, and the other electrode of the cell20is defined as a negative electrode of the cell20. In addition, the circuit board is approximately a cuboid structure. Therefore, a length of the circuit board is defined as a maximum spacing between a pair of two opposite ends of the circuit board, a height of the circuit board is defined as a minimum spacing between the other pair of two opposite ends of the circuit board, and a width of the circuit board is defined as a spacing between the remaining pair of two opposite ends of the circuit board.

It is hereby noted that a distance between one end of the circuit board40along the length direction of the circuit board and a first surface111ais a first spacing S1, and a distance between the other end of the circuit board40along the length direction of the circuit board and the first surface111ais a second spacing S2. Preferably, S1 and S2 satisfy: |S1-S2|=0 mm. That is, in the length direction of the circuit board, the circuit board40is disposed parallel to the first surface111a. However, during assembling, the step of fixing both the first conductive sheet20and the second conductive sheet30to the circuit board40inevitably causes a problem of an assembly tolerance. Therefore, the circuit board40is deemed parallel to the first surface111ain the length direction of the circuit board even if |S1-S2| is less than or equal to 1 mm.

In this embodiment of this application, the spacing between the circuit board40and the surface of the metal housing110is controlled, so that the circuit board40is approximately parallel to the surface of the metal housing110, thereby making it convenient to affix insulation tape outside the circuit board40or perform low-pressure injection molding on the circuit board40to form a protective body. In addition, the installation space occupied by the circuit board40is reduced, and in turn, the space occupied by the metal-shell battery is reduced, thereby meeting miniaturization and lightweight requirements of the metal-shell battery.

For the metal housing110above, still referring toFIG. 1, the metal housing110includes a first sidewall111, a second sidewall112, a third sidewall113, a fourth sidewall114, a fifth sidewall115, and a sixth sidewall116. The first sidewall111, the second sidewall112, the third sidewall113, and the fourth sidewall114are connected in sequence, and are connected to the oppositely disposed fifth sidewall115and sixth sidewall116separately to circumferentially form a closed space that is used to accommodate the cell20. For ease of description, in this embodiment of this application, a surface of the first sidewall111, a surface of the second sidewall112, a surface of the third sidewall113, a surface of the fourth sidewall114, a surface of the fifth sidewall115, and a surface of the sixth sidewall are defined as a first lateral surface, a second lateral surface (not shown), a third lateral surface (not shown), a fourth lateral surface (not shown), a fifth lateral surface, and a sixth lateral surface (not shown) of the metal housing110. The first surface111ais the first lateral surface that is of the metal housing110and that is close to the circuit board40. The second surface115ais the fifth lateral surface that is disposed adjacent to the first surface111aand that is of the metal housing110.

Understandably, the material and shape of the metal housing110are adaptively adjustable according to actual needs. For example, in this embodiment of this application, the metal-shell battery is installed inside a frame of a smart wearable device as a power supply of the smart wearable device. Therefore, in order to achieve high mechanical performance of the metal-shell battery, the material of the metal housing110may be steel alloy, and the shape of the metal housing110is approximately a cuboid. Definitely, in other embodiments of this application, the material of the metal housing110may be aluminum alloy, iron alloy, copper alloy, nickel alloy, stainless steel, or the like instead, and the shape of the metal housing110may be a regular structure such as a columnar structure instead.

Further, still referring toFIG. 2, a first opening110aand a second opening110bare made on the metal housing110. The first opening110aand the second opening110bcommunicate with each other in a closed space. The first opening110ais configured to replenish or replace an electrolytic solution of the cell20. The second opening110bis configured to allow passage of a positive electrode of the cell20. It is hereby noted that, in order to prevent the injected electrolytic solution140from leaking out or to prevent external impurities from entering the closed space, a plug117is further disposed at the first opening110ain this embodiment of this application. The plug117is configured to hermetically seal the first opening110a. In addition, in order to avoid a short circuit between the positive electrode and a negative electrode of the cell20, an insulation spacer118is further disposed at the second opening110bin this embodiment of this application. The insulation spacer118is configured to insulate the positive electrode from the negative electrode of the cell20and also prevent the electrolytic solution140from leaking out of the second opening110b.

Understandably, positions of the first opening110aand the second opening110bare adaptively adjustable according to actual needs. For example, in this embodiment of the application, in order to reduce processing steps of the metal housing110, the first opening110aand the second opening110bcan be drilled on the same surface of the metal housing110by using processing equipment without a need to adjust a posture of fixing the metal housing110. For example, the surface is the first surface111a. Further, the first opening110ais located at an end that is of the first surface111aand that is close to the second lateral surface120a. The second opening110bis located at an end that is of the first surface111aand that is close to the fourth lateral surface140a. Definitely, in other embodiments of this application, the first opening110aand the second opening110bmay be located on different surfaces of the metal housing110instead.

For the cell20, referring toFIG. 3, the cell20further includes a positive tab131, a negative tab132, and an electrolytic solution140. The electrolytic solution140is accommodated in a closed space inside the metal housing110. The electrode assembly120is infiltrated in the electrolytic solution140. One end of the positive tab131and one end of the negative tab132are electrically connected to the electrode assembly120separately. The other end of the positive tab131protrudes from the first opening110bin the form of an electrode post. Preferably, a cross section of the electrode post is a circular or rectangular shape, and a gap exists between an end surface of an end that is of the electrode post and that is away from the positive tab131and the first surface111a. The other end of the negative tab132is electrically connected to any sidewall of the metal housing110.

Specifically, the electrode assembly120is a stacked structure. The electrode assembly120includes a positive electrode plate121, a negative electrode plate122, and a separator123. The positive electrode plate121and the negative electrode plate122are alternately stacked. A separator123is disposed between any adjacent positive electrode plate121and negative electrode plate122.

Understandably, the number of layers of the positive electrode plate121and the negative electrode plate122is not limited, and is adaptively adjustable according to actual needs. For example, in this embodiment of this application, to minimize the space occupied by the cell20, the number of layers of the positive electrode plate121and the negative electrode plate122is preferably 1 or 2. Definitely, in other embodiments of this application, the number of layers of the positive electrode plate121and the negative electrode plate122may be more than 3 instead. In addition, in order to make the electrolytic solution140infiltrate the electrode assembly120thoroughly and improve an energy density of the metal-shell battery, in other embodiments of this application, the electrode assembly120may be a jelly-roll structure instead. That is, a jelly-roll cell is formed. In sealing the electrode assembly120, due to a gap between the electrode assembly120and the metal housing110, the electrolytic solution140can easily flow through the gaps and enter the stacked layers of the electrode assembly120.

For the first conductive sheet20, referring toFIG. 3andFIG. 4together, the first conductive sheet20includes a first fixing portion210, a first connecting portion220, and a second fixing portion230. The first fixing portion210is disposed at one end of the first connecting portion220. The second fixing portion230is disposed at the other end of the first connecting portion220. The first fixing portion210is disposed at an angle to the second fixing portion230. The first fixing portion210is connected to an end surface that is of the electrode post and that is away from the positive tab131. The second fixing portion230is connected to the circuit board40.

Understandably, the material and structure of the first conductive sheet20are adaptively adjustable according to actual needs. For example, in this embodiment of this application, due to a relatively small gap between the electrode post and the circuit board40, for ease of fixing the first conductive sheet20between the electrode post and the circuit board40, the material of the first conductive sheet20may be nickel alloy, and the shape of the first conductive sheet20is approximately a cuboid. Definitely, in other embodiments of this application, the material of the first conductive sheet20may be copper alloy or aluminum alloy instead, and the shape of the first conductive sheet20may be a regular structure such as a strip shape or a block shape instead.

Understandably, the electrode post may be connected to the circuit board40by a means other than the first conductive sheet20. For example, in other embodiments of this application, the gap between the electrode post and the circuit board40is filled with tin so that the electrode post is directly welded and fixed onto the circuit board40to implement electrical connection between the electrode post and the circuit board40.

For the second conductive sheet30, the second conductive sheet30includes a third fixing portion310, a second connecting portion320, and a fourth fixing portion330. The third fixing portion310is disposed at one end of the second connecting portion320. The fourth fixing portion330is disposed at the other end of the second connecting portion320. The third fixing portion310is disposed at an angle to the fourth fixing portion330. The third fixing portion310is connected to the first surface111a. The fourth fixing portion330is connected to the circuit board40.

Understandably, the material and structure of the second conductive sheet30are adaptively adjustable according to actual needs. For example, in this embodiment of this application, due to a relatively small gap between the first surface111aand the circuit board40, for ease of fixing the second conductive sheet30between the first surface111aand the circuit board40, the material of the second conductive sheet30may be nickel alloy, and the shape of the second conductive sheet30is approximately a cuboid. Definitely, in other embodiments of this application, the material of the second conductive sheet30may be copper alloy or aluminum alloy instead, and the shape of the second conductive sheet30may be a regular structure such as a strip shape or a block shape instead.

Understandably, the first surface111amay be connected to the circuit board40by a means other than the second conductive sheet30. For example, in other embodiments of this application, the gap between the first surface111aand the circuit board40is filled with tin so that the first surface111ais directly welded and fixed onto the circuit board40to implement electrical connection between the first surface111aand the circuit board40.

In addition, in order to ensure that just a small plastic deformation occurs when the circuit board40is disposed at an angle to the first surface111a, in this embodiment of the application, preferably, one of the first conductive sheet20or the second conductive sheet30may be of relatively high strength. Correspondingly, the strength of the other of the first conductive sheet20or the second conductive sheet30may be equal to or slightly lower than the strength of the former conductive sheet.

For the circuit board40, still referring toFIG. 1andFIG. 2, the circuit board40includes a circuit board body410and a first plane410a. The first plane410ais located on a side that is of the circuit board body410and that faces the first surface111a. Bonding pads are disposed on the first plane410a. The second fixing portion230and the fourth fixing portion330are connected to the bonding pads in one-to-one correspondence respectively. An output terminal420is disposed on the circuit board body410. Preferably, each bonding pad is in a sheet-like shape. The output terminal420is a flexible circuit board40.

Understandably, a trace mode of the output terminal420is adaptively adjustable according to actual needs. Alternatively, the output terminal420may be replaced by other materials, details of which are omitted here.

To facilitate balancing of the circuit board body410relative to the first surface111a, in some embodiments, the metal-shell battery further includes an insulation filler50. One end of the insulation filler50is connected to the first surface111a. The other end of the insulation filler50is connected to the first plane410a. Preferably, the number of insulation fillers50is two, of which one insulation filler50is located between the first conductive sheet20and the second conductive sheet30, and the other insulation filler50is located at a side that is of the second conductive sheet30and that is close to the fourth lateral surface140a. The insulation fillers50may be foam, silicone, or plastic. With the insulation filler50disposed between the circuit board and the first surface, the spacing between the circuit board and the first surface can be controlled more precisely, so that the circuit board is approximately parallel to the first surface.

To seal the circuit board40, the first conductive sheet20, and the second conductive sheet30in such a way that they are located outside the metal housing110, in some embodiments, the metal-shell battery further includes a protection piece70. The protection piece70is adhered onto the first surface111. The protection piece70at least partly overlays the circuit board40. Preferably, the protection piece70completely coats the circuit board40, the first conductive sheet20, and the second conductive sheet30. In some embodiments, the protection piece70is directly formed on the first surface111aby means of low-pressure injection molding, thereby increasing connection strength between the circuit board40and the cell10and improving protection effects on the circuit board40.

For ease of understanding the content of the first embodiment of this application, the following describes the content with reference to a process flow of assembling a pack of a metal-shell battery.

S1: Space the circuit board40apart from the first surface111aby letting the first plane410abe perpendicular to the first surface111a. First, place the first conductive sheet20between the electrode post and the circuit board40, and then weld and fix the first conductive sheet20onto a bonding pad between the electrode post and the circuit board40by welding.

S2: Place the second conductive sheet30between the first surface111aand the circuit board40, and then weld and fix the second conductive sheet30onto a bonding pad between the first surface111aand the circuit board40by welding.

S3: Dispose a filler between the first plane410aand the first surface111a.

S4: Bend the first conductive sheet20and the second conductive sheet30so that the first plane410ais parallel to the first surface111a.

S5: Perform potting, adhesive dispensing, or low-pressure injection molding to form a protection piece70to seal the circuit board40, the first conductive sheet20, and the second conductive sheet30on the first surface111a.

S6: Form the output terminal420by bending a flexible printed circuit (FPC), so that the other end of the output terminal420protrudes from the second lateral surface120a.

Understandably, through step S4, the first plane410aof the circuit board40closely fits the first surface111ato minimize the gap between the first plane410aand the first surface111ain a width direction of the circuit board40. Preferably, an angle α1 between the first plane410aand the first surface111ain the width direction of the circuit board40is 0°. In other words, the first plane410ais disposed parallel to the first surface111aalong the width direction of the circuit board40. However, due to a problem of a packaging tolerance that unavoidably arises from the bending of the first conductive sheet20, the second conductive sheet30, and the circuit board40in step S4, the first plane410aof the circuit board40is disposed at an angle to the first surface111ain the width direction of the circuit board40. To be specific, the angle α1 between the first plane410aand the first surface111asatisfies: 0°≤α1≤30°. The angle falling within such a range can meet requirements in practical applications.

Further, understandably, an area of an orthographic projection of the protection piece70obtained in step S5 on the first surface111ais smaller than a surface area of the first surface111a. In other words, when the protection piece70is adhered to the metal housing110, a surface of the protection piece70partly overlays the first surface111a. In this way, when the protection piece70is plugged to an external device equipped with a socket that matches the protection piece70, the metal-shell battery can be fixed onto the external device more firmly.

In this embodiment of this application, the first conductive sheet20and the second conductive sheet30are disposed between the circuit board40and two electrodes of the cell20respectively, so that a plane in which the circuit board40is located is approximately parallel to the first surface111aof the cell20. In contrast to the prior art, this embodiment of this application reduces the installation space occupied by the circuit board40, and in turn, reduces the space occupied by the metal-shell battery, thereby meeting the miniaturization and lightweight requirements of the metal-shell battery.

In addition, the insulation filler50disposed between the circuit board40and the first surface111acan not only support the circuit board40, but also effectively avoid skew of the circuit board in a process of bending the first conductive sheet20and the second conductive sheet30.

Referring toFIG. 4, which shows a metal-shell battery according to a second embodiment of this application. The second embodiment differs from the first embodiment in that the step of bending the first conductive sheet20and the second conductive sheet30and the step of forming the output terminal420by bending an FPC in the process of assembling the pack of the metal-shell battery are omitted.

In the second embodiment, the first plane410ais disposed at an angle to the first surface111a, and the angle α2 between the first plane410aand the first surface111asatisfies: 80°≤α2≤100°. Preferably, the angle α2 between the first plane410aand the first surface111ais 90°, that is, the first plane410ais perpendicular to the first surface111ain the length direction of the circuit board.

Referring toFIG. 5toFIG. 7together, which show a metal-shell battery according to a third embodiment of this application. The third embodiment differs from the first embodiment in a manner of connection between the second conductive sheet30and the first surface111a.

In the third embodiment, the metal-shell battery further includes a pantograph strip60. A flat portion of the pantograph strip60is disposed on the first surface111a. A raised portion of the pantograph strip60is away from the first surface111a. The first fixing portion210is connected to the raised portion. With the pantograph strip60in use, a weld point of the first conductive sheet20and a weld point of the second conductive sheet30are approximately located at the same height. In this way, by means of laser welding, the first conductive sheet20and the second conductive sheet30can be welded in the same process, without producing different welding effects due to different laser effecting distances caused by different welding heights of the two conductive sheets. Preferably, the first fixing portion210snugly fits a surface that is of the raised portion and that is away from the first surface111a. The pantograph strip60may be made of steel alloy or stainless steel. Understandably, the insulation filler50are adaptively adjustable according to actual needs.

Referring toFIG. 8, which shows a metal-shell battery according a fourth embodiment of this application. The fourth embodiment differs from the first embodiment in that the insulation filler50is replaced with insulation tape.

In the fourth embodiment, the insulation filler50between the first surface111aand the first plane410ais replaced with the insulation tape80. Preferably, the insulation tape80is an integrated structure. Two through-holes are made on the insulation tape to facilitate exposure of the first conductive sheet20and the second conductive sheet30. Two opposite sides of the insulation tape are connected to the second lateral surface120aand the fourth lateral surface140arespectively. A side located between the two opposite sides of the insulation tape is connected to the second surface115a, thereby preventing direct electrical contact between the circuit board40and the metal housing110.

Referring toFIG. 9, which shows a metal-shell battery according to a fifth embodiment of this application. The fifth embodiment differs from the fourth embodiment in that the insulation tape located between the first surface111aand the first plane410ais a discrete structure.

This application further provides an electronic device, including the metal-shell battery described above. For a specific structure and functions of the metal-shell battery, refer to the foregoing embodiments, details of which are not repeated herein. The electronic device may be a mobile electronic device, an energy storage device, an electric vehicle, a hybrid electric vehicle, or the like. The mobile device may be a mobile phone, a wearable electronic device, a tablet computer, a notebook computer, or the like.

What is described above is merely embodiments of this application, and is not to hereby limit the patent scope of this application. All equivalent structural variations and equivalent process variations made by using the content of the specification and the drawings hereof, and any direct and indirect use of the content hereof in other related technical fields, fall within the patent protection scope of this application.