CN219017865U

CN219017865U - Battery and electronic equipment

Info

Publication number: CN219017865U
Application number: CN202223019764.4U
Authority: CN
Inventors: 朱明富; 林冬梅; 胡庆波
Original assignee: Linkdata New Energy Co Ltd
Current assignee: Linkdata New Energy Co Ltd
Priority date: 2022-11-14
Filing date: 2022-11-14
Publication date: 2023-05-12
Anticipated expiration: 2032-11-14

Abstract

The application provides a battery and electronic equipment. The battery comprises a shell and an electrode assembly accommodated in the shell, wherein the electrode assembly comprises a positive electrode plate, a negative electrode plate and a separation film arranged between the positive electrode plate and the negative electrode plate; the positive pole piece, the isolating film and the negative pole piece are laminated and wound into a winding structure, and an electrode assembly of the winding structure is provided with a central hole; the positive electrode tab is bent towards the connecting sheet and welded with the connecting sheet, the orthographic projection of the central hole falls into the orthographic projection of the connecting sheet along the extending direction of the shell, and the connecting sheet is welded with the first end of the shell in the orthographic projection of the central hole. According to the battery welding structure, the battery impedance can be reduced to improve the charging and discharging power, the space occupied by the tab welding structure in the height direction of the battery is reduced, so that the energy density can be increased, and in addition, the welding process can be simplified to be beneficial to improving the production efficiency.

Description

Battery and electronic equipment

Technical Field

The application relates to the technical field of batteries, in particular to a battery and electronic equipment.

Background

Currently, with the widespread use of lithium ion batteries in electric vehicles and other fields, a user group requires higher energy density and power output for the battery. The multipolar ear battery is applied, and the multipolar ear battery is understood to be a battery provided with a plurality of positive electrode tabs and a plurality of negative electrode tabs, wherein the plurality of positive electrode tabs are welded with a positive electrode connecting piece and are electrically connected with a positive electrode post of the battery, and the plurality of negative electrode tabs are welded with a negative electrode connecting piece and are electrically connected with a negative electrode post of the battery, so that the multipolar ear battery has lower battery impedance due to larger current sectional area and further has higher output power, and therefore, the multipolar ear battery has been widely developed and applied in industry. At present most multipolar ear battery is the aluminum part, when the apron welding of a plurality of anodal utmost point ears and casing bottom, the weldability effect of aluminum part is relatively poor, can lead to the welding needle to be corroded fast, need frequent loading and unloading in order to polish cleanly to the adhesion (sticking needle phenomenon promptly) of welding needle and a plurality of anodal utmost point ears in the welding process frequently causes welding stability relatively poor, for example appears rosin joint, welding slag splash and the risk that the welding penetration leads to the weeping is higher.

Disclosure of Invention

In view of this, this application provides a battery and electronic equipment, can improve the battery multipolar ear poor stability and lead to the problem of weeping such as cold joint, welding slag splash and welding through, also can improve the operation complicacy that frequently changes the welding needle and be unfavorable for automated production's problem.

The battery comprises a shell and an electrode assembly accommodated in the shell, wherein the electrode assembly comprises a positive electrode plate, a negative electrode plate and a separation film arranged between the positive electrode plate and the negative electrode plate; the positive pole piece, the isolating film and the negative pole piece are laminated and wound into a winding structure, and an electrode assembly of the winding structure is provided with a central hole; the positive electrode tab is bent towards the connecting sheet and welded with the connecting sheet, the orthographic projection of the central hole falls into the orthographic projection of the connecting sheet along the extending direction of the shell, and the connecting sheet is welded with the first end of the shell in the orthographic projection of the central hole.

Optionally, the positive pole piece is provided with a plurality of positive pole tabs arranged at intervals along the winding direction, the bent positive pole tabs are sequentially overlapped, and at least a part of the positive pole tabs are welded with the connecting sheet.

Optionally, along the extending direction of the housing, the orthographic projection of the central hole and the orthographic projection of the positive electrode tab do not overlap.

Optionally, the positive electrode tab of the positive electrode plate is of an integral structure.

Optionally, the positive electrode tab is an aluminum piece, and the positive electrode tab and the first end of the shell are welded in an ultrasonic welding mode.

An electronic device provided by the application comprises a load and a battery as claimed in any one of the above, wherein the battery is used for supplying power to the load.

As described above, the battery of the application is of a winding structure with a central hole, the positive electrode tab and the shell are welded through the connecting sheet, but the positive electrode tab and the shell are not directly welded, the application allows the electrode assembly of the winding structure to be welded with a plurality of positive electrode tabs and the connecting sheet before being put into the shell, the operation space is large, the welding operation is convenient, after the electrode assembly of the winding structure is put into the shell, the welding needle can penetrate through the central hole and weld the connecting sheet and the shell, compared with the welding of a plurality of positive electrode tabs and the shell, the number of welded elements is small when the connecting sheet and the shell are welded, the welding area can be increased, the welding is simple, the welding stability is good, the risk of liquid leakage caused by the occurrence of false welding, slag splashing and welding penetration can be reduced, the cleaning of the welding needle is also facilitated, the frequency of replacing the welding needle is reduced, the welding operation is simplified, and the automatic production is facilitated.

Drawings

Fig. 1 is a schematic diagram of the overall structure of a battery according to an embodiment of the present application;

fig. 2 is a schematic structural diagram of an electrode assembly provided in an embodiment of the present application without stacking a plurality of positive electrode tabs;

fig. 3 is a schematic structural diagram of an electrode assembly according to an embodiment of the present disclosure stacked with a plurality of positive electrode tabs;

fig. 4 is a schematic structural diagram of a plurality of welded positive electrode tabs and connecting pieces according to an embodiment of the present disclosure;

fig. 5 is an expanded and tiled schematic view of a positive electrode plate and a negative electrode plate according to an embodiment of the present application;

fig. 6 is an expanded and tiled schematic view of another positive and negative electrode sheet according to an embodiment of the present application.

Detailed Description

The application provides a battery is for having the winding structure in centre bore, and anodal utmost point ear passes through the connection piece and welds with the first end of casing, can realize being connected with the electricity between the casing. Compare in direct welding a plurality of anodal lugs and casing, this application can provide great welding operable space to and simplify the welding degree of difficulty, with this welding stability that improves and ensure the welding needle cleanliness, do benefit to automated production.

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be clearly described below with reference to specific embodiments and corresponding drawings. It will be apparent that the embodiments described below are only some, but not all, of the embodiments of the present application. The following embodiments and technical features thereof may be combined with each other without conflict, and also belong to the technical solutions of the present application.

It should be understood that in the description of the embodiments of the present application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the technical solutions and simplifying the description of the corresponding embodiments of the present application, and do not indicate or imply that the device or element must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present application.

Referring to fig. 1 to 4, a battery 1 includes a case 11 and an electrode assembly 12.

The case 11 encloses the entire shape of the battery 1 and also serves to define the external appearance of the battery 1. In some cases, the housing 11 may be an integrally formed structure, for example, an aluminum plate may be manufactured by a stamping process. The housing 11 includes a side wall 11a and a bottom 11b, the bottom 11b being provided at a lower end of the side wall 11a, and the housing 11 having one end opened is formed. For convenience of description, the bottom 11b is considered as the first end of the housing 11 and the open end is considered as the second end of the housing 11 throughout this application, and in the arrangement orientation as shown in the drawings, the first end is the upper end and the second end is the lower end, it should be understood that as the arrangement orientation of the battery 1 changes, the various orientations of this application including the first end and the second end will change.

The side wall 11a and the bottom 11b are assembled to form a housing chamber 11c, and elements such as the electrode assembly 12 and the electrolyte of the battery 1 are housed in the housing chamber 11c, and these elements are protected by the case 11, thereby improving the protection effect and safety. The overall shape of the housing 11, the embodiments of the present application are not limited, and the cylinder is shown for illustrative purposes only. The shapes of the side wall 11a, the bottom 11b, the housing chamber 11c, and the electrode assembly 12 are determined according to the overall shape adaptability of the case 11.

The electrode assembly 12 may be formed by stacking and winding a plurality of positive electrode sheets and a plurality of negative electrode sheets, and the number of each electrode sheet is not limited in this application, and for example, one positive electrode sheet and one negative electrode sheet are formed by adopting other suitable winding manners. Isolation films (not shown) for realizing insulation of the positive pole piece and the negative pole pieces are arranged between the positive pole piece and the negative pole pieces, for example, the isolation films can be arranged on two sides of a single pole piece (which can be the positive pole piece or the negative pole piece). The electrode assembly 12 of the wound structure has a central hole 12a.

On a first side of the electrode assembly 12, as shown in fig. 1 to 6, the positive electrode tab 121 extends to form a positive electrode tab 131, such as an aluminum member, and the negative electrode tab 122 extends to form a negative electrode tab 132. The positive electrode tab 131 and the negative electrode tab 132 are respectively formed by extending corresponding current collectors, and are part of the respective corresponding current collectors, and may be formed by a process such as cutting. In the scenario shown in fig. 1-6, the first side of electrode assembly 12 is the underside of electrode assembly 12 and the second side is the underside of electrode assembly 12.

Referring to fig. 5 (a), the positive electrode tab 121 includes a positive electrode current collector 21 and a positive electrode active material layer 31 (shown in a hatched portion) disposed on a surface of the positive electrode current collector 21. The positive electrode current collector 21 includes a first surface and a second surface that are disposed opposite to each other in the own thickness direction, and is provided with a positive electrode active material layer 31. Only one of the surfaces of the positive electrode tab 121 is shown in fig. 5.

The embodiment of the present application does not limit the shape of the positive electrode current collector 21, and a rectangular positive electrode current collector 21 is described herein as an example. The positive electrode current collector 21 includes a first side 211, a second side 212, a third side 213, and a fourth side 214, the first side 211 and the second side 212 are perpendicularly intersected, the third side 213 and the fourth side 214 are perpendicularly intersected, the first side 211 and the third side 213 are oppositely arranged along a second direction y, in the unfolded and tiled state of the positive electrode current collector 21, the extending directions of the first side 211 and the third side 213 are all in a third direction z, and the second side 212 and the fourth side 214 are oppositely arranged along the third direction z. Throughout this application, the two bodies are arranged opposite to each other in a certain direction, and it is understood that: in a certain direction the two bodies are not in contact, i.e. have a distance different from zero.

In some embodiments, the positive electrode tab 131 may be formed by a first side 211 (lower side) of the positive electrode current collector 21 protruding toward the opposite direction of the second direction y, the first side 211 being the side of the positive electrode current collector 21 closest to the first end (i.e., the bottom 11 b) of the case 11. The width of the positive electrode tab 131 is smaller than the length of the first side 211 (for example, the third direction z in the unfolded and flat state of the positive electrode current collector 21 in fig. 5 or 6). For the electrode assembly 12 of the rolled structure, the width of the positive electrode tab 131 is a length in the rolling direction, and the lengths of the first side 211 and the positive electrode current collector 21 are lengths in the rolling direction.

In the battery 1 of the embodiment of the application, the battery 1 is provided with the connecting piece 10, the positive electrode tab 131 is bent towards the connecting piece 10 and welded with the connecting piece 10, the orthographic projection of the central hole 12a of the electrode assembly 12 falls into the orthographic projection of the connecting piece 10 along the extending direction y of the shell 11, and in the orthographic projection of the central hole 12a, the connecting piece 10 is welded with the first end 11b of the shell 11, so that the electrical connection between the positive electrode tab 131 and the shell 11 can be realized. The configuration of the lower end portion of the battery 1 can be expressed as: on the lower side of the electrode assembly 12, the center hole 12a is covered by the connection piece 10, and the orthographic projection of the center hole 12a and the orthographic projection of the positive electrode tab 131 are not overlapped in the extending direction y of the case 11, that is, the positive electrode tab 131 and the center hole 12a are not overlapped or covered at all. The welding includes, but is not limited to, welding by ultrasonic welding.

According to the electrode assembly 12 with the winding structure, the positive electrode tab 131 and the shell 11 are welded through the connecting sheet 10, instead of directly welding the positive electrode tab 131 and the shell 11, the electrode assembly 12 with the winding structure is allowed to weld one or more positive electrode tabs 131 and the connecting sheet 10 before being placed into the shell 11, optionally the welding mark 10a is located in the connecting sheet 10, the operation space is large, welding operation is convenient, after the electrode assembly 13 with the winding structure is placed into the shell 11, a welding needle can penetrate through the central hole 12a and weld the connecting sheet 10 and the shell 11, optionally the welding mark 12c is only located in the orthographic projection area of the central hole 12a, compared with the fact that one or more positive electrode tabs 131 and the shell 11 are directly welded, the number of welded elements is small when the connecting sheet 10 and the shell 11 are welded, the welding area can be increased, even for the positive electrode tab 131 of an aluminum piece, the welding operation is simple, the welding stability is good, the risks of welding needle, such as welding slag splashing and liquid leakage caused by the virtual welding can be reduced, the welding needle can be kept clean, the number of times of automatic replacement of the welding needle is reduced, and the automatic production operation is facilitated.

In addition, the positive electrode tab 131 has a sheet-like structure, so that the area of the positive electrode tab 131 is considered to be large, the impedance of the battery 1 can be reduced, and the charge and discharge power can be improved.

In some cases, along the extending direction of the first side 211, for example, referring to fig. 5 (a), in the unfolded and tiled state of the positive current collector 21, along the third direction z or along the winding direction of the positive electrode tab 121, the first side 211 of the positive current collector 21 protrudes to form a plurality of positive electrode tabs 131 disposed at intervals.

The same current collector adopts a plurality of positive electrode lugs 131 which are arranged at intervals, which is beneficial to releasing stress generated by bending of the positive electrode current collector 21 when the positive electrode plate 121 is wound. In addition, the plurality of positive electrode tabs 131 after bending are sequentially overlapped, at least a part of the positive electrode tabs 131 are overlapped with the connecting sheet 10, and even if insufficient welding or welding flaws occur, one or more positive electrode tabs 131 can be welded with the connecting sheet 10, so that electric connection between all the positive electrode tabs 131 and the bottom 11b of the shell 11 is realized, and the accuracy of welding positions and required professional requirements can be reduced.

In some cases, the plurality of positive electrode tabs 131 after winding may be located in different winding circles, where the lengths of the plurality of positive electrode tabs 131 are different along the direction of the first side 211 of the electrode assembly 12 toward the central hole 12a (i.e., the winding radius direction). In other cases, if the plurality of positive electrode tabs 131 after winding are located at the same winding turn in a direction toward the central hole 12a along the first side 211 of the electrode assembly 12, the lengths of the plurality of positive electrode tabs 131 may be the same.

Referring to fig. 5 (b), the positive electrode tab 131 of the positive electrode tab 121 may be an integral structure, that is, only one positive electrode tab 131 may be disposed on the positive electrode tab 121.

With continued reference to fig. 1-4, on a second (e.g., upper) side of the electrode assembly 12, the negative electrode tab 122 is provided with a negative electrode tab 132.

In the case shown in fig. 5 (b), the electrode assembly 12 may be provided with a plurality of negative electrode tabs 132 disposed at intervals. Alternatively, a single negative electrode tab 132 as shown in fig. 5 (b) is provided.

The negative electrode tab 122 includes a negative electrode current collector 22 and a negative electrode active material layer 32 disposed on the negative electrode current collector 22. The present application describes, as an example, a rectangular negative electrode current collector 22 without limiting the shape of the negative electrode current collector 22. The negative current collector 22 includes a fifth side 221, a sixth side 222, a seventh side 223, and an eighth side 224, the fifth side 221 and the sixth side 222 vertically intersect, the seventh side 223 and the eighth side 224 vertically intersect, the fifth side 221 and the seventh side 223 are oppositely disposed along the second direction y, in the unfolded and tiled state of the negative current collector 22, the extending directions of the fifth side 221 and the seventh side 223 are both the third direction z, and the sixth side 222 and the eighth side 224 are oppositely disposed along the third direction z.

In some embodiments, the negative electrode tab 132 may be formed by a fifth side 211 (upper side) of the negative electrode current collector 22 protruding toward the second direction y, the fifth side 211 being a side of the negative electrode current collector 22 closest to the second end (i.e., the top opening) of the case 11. The width of the negative electrode tab 132 is smaller than the length of the fifth side 211 (e.g., along the third direction z in the unfolded and flat state of the negative electrode current collector 22 in fig. 5 or 6). For the electrode assembly 12 of the rolled structure, the width of the negative electrode tab 132 is the length in the rolling direction, and the lengths of the fifth side 211 and the negative electrode current collector 22 are the lengths in the rolling direction.

The battery 1 further comprises a negative electrode connecting piece 14, the negative electrode connecting piece 14 is connected with the negative electrode tab 132, and the connecting part is staggered with the central hole 12a, so that the negative electrode connecting piece 14 or the negative electrode tab 132 cannot interfere with a welding needle in the welding process, and the welding needle is facilitated to be inserted into the central hole 12a.

It should be understood that the battery 1 may also include other structures, not listed here. For example, referring to fig. 1, the battery 1 further includes a cover plate 15, a post (i.e. a negative electrode post) 151 penetrating through the thickness of the cover plate 15 is disposed on the cover plate 15, the negative electrode connecting member 14 is connected to the post 151, and the cover plate 15 covers the opening at the upper end of the housing 11. And electrolyte is injected through the injection hole of the cover plate 15. If the lengths of the negative electrode connection member 14 and the negative electrode tab 132 are large, the negative electrode connection member 14 and the negative electrode tab 132 may be bent or folded, and then the cover plate 15 may cover the opening of the upper end of the case 11; for another example, an insulating spacer may be provided between the upper end of the electrode assembly 12 and the cap plate 15 to electrically insulate the electrode assembly 12 from the cap plate 13 to avoid shorting. The insulating spacer may be provided with a plurality of through holes to facilitate electrolyte infiltration into the region of the case 11 where the electrode assembly 12 is housed.

The embodiment of the application also provides an electronic device, which comprises a load and the battery 1 of any embodiment, wherein the battery 1 is used for supplying power to the load. Since the electronic device has the battery 1 of any of the foregoing embodiments, the electronic device can produce the advantageous effects that the battery 1 of the corresponding embodiment has.

The electronic device may be embodied in various specific forms, for example, an electronic product such as an unmanned aerial vehicle, an electric cleaning tool, an energy storage product, an electric vehicle, an electric bicycle, an electric navigation tool, or the like. In a practical scenario, the electronic device specifically includes, but is not limited to,: standby power, electric motor, automobile, motorcycle, booster bicycle, bicycle electric tool, household large-scale accumulator, lithium ion capacitor, etc.

It will be appreciated by those skilled in the art that the configuration according to the embodiments of the present application can be applied to a stationary type electronic apparatus in addition to an element particularly used for a moving purpose.

The foregoing description is only a partial embodiment of the present application and is not intended to limit the scope of the patent application, and it is intended that all equivalent structural modifications made by those skilled in the art using the present description and accompanying drawings be included in the scope of the patent application.

Although the terms first, second, etc. are used herein to describe various information, these information should not be limited by these terms. These terms are only used to distinguish one type of information from another. In addition, the singular forms "a", "an" and "the" are intended to include the plural forms as well. The terms "or" and/or "are to be construed as inclusive, or mean any one or any combination. An exception to this definition will occur only when a combination of elements, functions, steps or operations are in some way inherently mutually exclusive.

Claims

1. A battery comprises a shell and an electrode assembly accommodated in the shell, wherein the electrode assembly comprises a positive electrode plate, a negative electrode plate and a separation film arranged between the positive electrode plate and the negative electrode plate;

the positive electrode plate, the isolating film and the negative electrode plate are laminated and wound into a winding structure, and an electrode assembly of the winding structure is provided with a central hole;

the positive electrode tab is bent towards the connecting sheet and welded with the connecting sheet, the orthographic projection of the central hole falls into the orthographic projection of the connecting sheet along the extending direction of the shell, and the connecting sheet is welded with the first end of the shell in the orthographic projection of the central hole.

2. The battery according to claim 1, wherein the positive electrode sheet is provided with a plurality of the positive electrode tabs arranged at intervals in a winding direction, the plurality of the positive electrode tabs after bending are sequentially overlapped, and at least a part of the positive electrode tabs are welded with the connecting piece.

3. The battery according to claim 1 or 2, wherein the orthographic projection of the center hole and the orthographic projection of the positive electrode tab do not overlap in the extending direction of the case.

4. The battery of claim 1, wherein the positive tab of the positive electrode tab is of unitary construction.

5. The battery of claim 1, wherein the positive electrode tab is an aluminum piece, and the positive electrode tab and the first end of the housing are welded by ultrasonic welding.

6. An electronic device comprising a load and a battery as claimed in any one of the preceding claims 1 to 5, the battery being arranged to supply power to the load.