CN219959187U

CN219959187U - Cover plate assembly for secondary battery and secondary battery

Info

Publication number: CN219959187U
Application number: CN202321473250.8U
Authority: CN
Inventors: 王举; 冯树南
Original assignee: Lanjing New Energy Jiaxing Co ltd
Current assignee: Lanjing New Energy Jiaxing Co ltd
Priority date: 2023-06-09
Filing date: 2023-06-09
Publication date: 2023-11-03
Anticipated expiration: 2033-06-09

Abstract

The utility model provides a cover plate assembly for a secondary battery and the secondary battery, comprising: the side wall of the current collector extends outwards to form a welding lug, and the welding lug can be bent; the welding lug is connected with the cover plate; the insulating piece is arranged between the current collector and the cover plate; when the welding lugs are in a bending state, the current collector corresponds to the cover plate in position. The utility model has the beneficial effects that: welding an explosion-proof piece with a cover plate, placing an insulating piece, finally welding a welding lug and the cover plate, welding a current collector with a battery cell, bending the welding lug to enable the current collector to enter a positioning groove, putting the battery cell and a positioning boss into a battery shell, and finally welding the cover plate and the battery shell, wherein the concentricity of the battery cell and the cover plate is convenient to adjust in a mode of bending the welding lug.

Description

Cover plate assembly for secondary battery and secondary battery

Technical Field

The utility model belongs to the technical field of lithium ion batteries, and particularly relates to a cover plate assembly for a secondary battery and the secondary battery.

Background

The installation forms of the cover plates at the two ends of the traditional cylindrical aluminum shell battery are as follows: firstly, the positive and negative current collectors are connected with each other by a welding method, and in the welding process, the positive and negative current collectors are respectively and electrically connected with the positive and negative plates of the battery cell by a welding method, so that the concentricity of the battery cell and the cover plate can not be ensured due to the mounting structure, and the subsequent shell-entering operation is difficult; secondly, the cover plates on two sides are in a pole riveting mode, and the cost of pole riveting cover plates is high; thirdly, a cylindrical aluminum shell battery negative electrode side adopts a pole riveting cover plate mode, a positive electrode adopts a U-shaped single-pass aluminum shell, the connection of the positive electrode side is used for electrically connecting a shell and a current collector through penetration welding, the welding yield is low, and the welding quality cannot be guaranteed.

Disclosure of Invention

In view of the foregoing, the present utility model is directed to a cap assembly for a secondary battery and a secondary battery, which are intended to solve at least one of the above-mentioned problems.

In order to achieve the above purpose, the technical scheme of the utility model is realized as follows:

in one aspect, the present utility model provides a cap assembly for a secondary battery, comprising:

the side wall of the current collector extends outwards to form a welding lug, and the welding lug can be bent;

the welding lug is connected with the cover plate;

the insulating piece is arranged between the current collector and the cover plate;

when the welding lugs are in a bending state, the current collector corresponds to the cover plate in position.

Further, a plurality of supporting bosses are fixedly arranged on the end face, close to the current collector, of the insulating piece, positioning grooves are formed between the adjacent supporting bosses, and the width of each positioning groove is matched with the width of each welding lug;

the support boss is provided with a first liquid penetrating hole penetrating through the insulating piece;

the support boss is fixedly provided with a limit boss corresponding to the current collector, a plurality of limit grooves are formed between the limit bosses, and when the welding lugs are in a bending state, the current collector is arranged on the inner side of the limit grooves.

Further, a first positioning boss is fixedly arranged on the end face, close to the battery shell, of the cover plate, and the outer diameter of the first positioning boss is matched with the inner diameter of the battery shell;

a second positioning boss is fixedly arranged on the end face, close to the battery shell, of the first positioning boss, and the outer side edge, close to one end of the welding lug, of the second positioning boss adopts a chamfering structure;

the insulating piece is provided with a first positioning hole matched with the positioning boss, and the second positioning boss is arranged on the inner side of the first positioning hole.

Further, the end face of the welding lug far away from the cover plate is provided with a welding groove corresponding to the positioning boss in a two-phase mode, and the welding lug is welded with the cover plate at the position of the welding groove.

Further, a first liquid injection hole penetrating through the cover plate is formed in the first positioning boss, and the first liquid injection hole and the cover plate are coaxially arranged;

the end face of the cover plate, which is far away from the current collector, is provided with a liquid injection counter bore corresponding to the liquid injection hole I;

and a second liquid injection hole corresponding to the first liquid injection hole is formed in the welding lug.

Further, a strip-shaped bending hole is formed in the bending part of the welding lug, and a semicircular bending hole corresponding to the strip-shaped bending hole is formed in the side wall of the welding lug;

the insulating part is fixedly provided with a positioning column, the welding lug is provided with a positioning hole II matched with the positioning column, and the positioning column is arranged on the inner side of the positioning hole II.

Further, the number of the strip-shaped bending holes is two, reinforcing ribs I arranged along the length direction of the welding lug are arranged between the two strip-shaped bending holes, and the reinforcing ribs I are formed by stamping.

Further, a second reinforcing rib in a shape of a Chinese character 'mi' is arranged on the current collector, the second reinforcing rib is formed by stamping, a second liquid-permeable hole is formed in the current collector, and a third liquid injection hole corresponding to the liquid injection Kong Erxiang is formed in the current collector.

Further, a first explosion-proof hole is formed in the cover plate, an explosion-proof counter bore corresponding to the first explosion-proof hole is formed in the end face, close to the current collector, of the cover plate, an explosion-proof sheet is arranged in the explosion-proof counter bore, the explosion-proof sheet seals the first explosion-proof hole, and the explosion-proof sheet is welded with the bottom end of the explosion-proof counter bore;

and the insulating piece is provided with a second explosion-proof hole corresponding to the first explosion-proof hole.

Another aspect of the present utility model provides a secondary battery characterized in that: the battery comprises a battery shell, an electric core and a cover plate assembly, wherein the cover plate assembly is used for the secondary battery according to one aspect.

Compared with the prior art, the cover plate assembly for the secondary battery and the secondary battery have the following beneficial effects:

(1) The cover plate assembly for the secondary battery comprises a cover plate, a battery shell, a battery core, a positioning lug, a cover plate, an insulating piece, a welding lug, a battery core, a positioning groove, a battery core, a positioning boss, a battery cover plate, a welding lug and a welding lug.

(2) According to the cover plate assembly for the secondary battery, the insulating piece is designed to facilitate bending of the welding lug and radial positioning of the current collector, the current collector battery core can be elastically pressed after assembly, the absorption of the height tolerance of the winding core is good, and the self-adaption is high.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description serve to explain the utility model. In the drawings:

fig. 1 is a schematic perspective view of a cover plate assembly in an unbent state of a welding lug according to an embodiment of the present utility model;

fig. 2 is a schematic diagram of an explosion structure of a cover plate assembly in an unbent state of a welding lug according to an embodiment of the utility model;

fig. 3 is a schematic perspective view of a cover assembly in a bent state of a welding lug according to an embodiment of the present utility model;

fig. 4 is a schematic view of a three-dimensional structure of a current collector according to an embodiment of the present utility model;

FIG. 5 is a schematic perspective view of an insulating member according to an embodiment of the present utility model;

FIG. 6 is a schematic diagram of a cover plate according to an embodiment of the utility model;

FIG. 7 is a schematic cross-sectional view of a cover assembly in an unbent state of a welding lug according to an embodiment of the present utility model;

fig. 8 is a schematic cross-sectional view of a cover assembly in a bent state of a welding lug according to an embodiment of the utility model.

Reference numerals illustrate:

1. a current collector; 2. an insulating member; 3. a cover plate; 4. explosion-proof sheet; 101. welding lugs; 102. a semicircular bending hole; 103. a bar-shaped bending hole; 104. a first reinforcing rib; 105. a third liquid injection hole; 106. a second reinforcing rib; 107. a second liquid permeation hole; 108. positioning holes II; 109. a second liquid injection hole; 201. positioning holes I; 202. a support boss; 203. a liquid permeation hole I; 204. a limit boss; 205. positioning columns; 206; explosion protection hole II; 301. positioning a first boss; 302. positioning a second boss; 303. explosion protection hole I; 304. a first liquid injection hole; 305. and (5) filling the liquid counter bore.

Detailed Description

It should be noted that, without conflict, the embodiments of the present utility model and features of the embodiments may be combined with each other.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first", "a second", etc. may explicitly or implicitly include one or more such feature. In the description of the present utility model, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art in a specific case.

The utility model will be described in detail below with reference to the drawings in connection with embodiments.

Embodiment one:

as shown in fig. 1 to 8, a cap assembly for a secondary battery includes:

the current collector 1, the side wall of the current collector 1 extends outwards to form a welding lug 101, and the welding lug 101 can be bent;

the cover plate 3, the welding lug 101 is connected with the cover plate 3;

an insulator 2, the insulator 2 being installed between the current collector 1 and the cap plate 3;

when the welding lug 101 is in a bent state, the current collector 1 corresponds to the position of the cover plate 3.

The cover plate 3, the current collector 1 and the insulating piece 2 are disc-shaped structural members, and the cover plate 3 and the current collector 1 are aluminum structural members; the insulating member 2 is a structural member made of plastic.

Four supporting bosses 202 are fixedly arranged on the end face, close to the current collector 1, of the insulating piece 2, positioning grooves are formed between the adjacent supporting bosses 202, the positioning grooves are convenient for installing the welding lugs 101 of the current collector 1 and storing the bent volumes, and meanwhile, under the combined action of the positioning grooves and the positioning columns 205, the positioning and installation of the conductive handles of the current collector disc are convenient, the positioning and welding of the central liquid injection holes are convenient, and the width of the positioning grooves is matched with that of the welding lugs 101; the supporting boss 202 is used for pressing the current collecting disc and the battery cell after the welding lug 101 of the current collector 1 is bent, so that the height tolerance of the battery cell can be absorbed.

The supporting boss 202 is provided with a plurality of first liquid penetrating holes 203 penetrating through the insulating piece 2; the first liquid-permeable hole 203 is used for circulation and infiltration of electrolyte.

The support boss 202 is fixedly provided with a limit boss 204 corresponding to the current collector 1, the limit boss 204 is of an arc-shaped structure, the inner diameter of the limit boss 204 of the arc-shaped structure is the same as the diameter of the current collector 1, limit grooves are formed among the limit bosses 204, and when the welding lugs 101 are in a bending state, the current collector 1 is arranged on the inner side of the limit grooves. The limiting boss 204 with the arc-shaped structure mainly plays a role in preventing the radial movement dislocation of the current collector 1 after the welding lug 101 of the current collector 1 is bent, and just clamps and positions the current collector 1.

The end face, close to the battery shell, of the cover plate 3 is fixedly provided with a first positioning boss 301, and the outer diameter of the first positioning boss 301 is matched with the inner diameter of the battery shell; the first positioning boss 301 facilitates the installation of the cover plate 3 into the battery case.

A second positioning boss 302 is fixedly arranged on the end face, close to the battery shell, of the first positioning boss 301, and the outer side edge, close to one end of the welding lug 101, of the second positioning boss 302 adopts a chamfer structure;

the insulator 2 is provided with a first positioning hole 201 matched with a second positioning boss 302, and the second positioning boss 302 is arranged on the inner side of the first positioning hole 201. The positioning lug plays a role in positioning the insulating piece 2.

The end face of the welding lug 101 far away from the cover plate 3 is provided with a welding groove corresponding to the second positioning boss 302, and the welding lug 101 is welded with the second positioning boss 302 of the cover plate 3 at the position of the welding groove. The upper end face of the positioning boss II 302 is in the same plane with the upper end face of the insulating member 2.

The first positioning boss 301 is provided with a first liquid injection hole 304 penetrating through the cover plate 3, and the first liquid injection hole 304 and the cover plate 3 are coaxially arranged;

the end face of the cover plate 3, which is far away from the current collector 1, is provided with a liquid injection counter bore 305 corresponding to the liquid injection hole one 304;

the welding lug 101 is provided with a second liquid injection hole 109 corresponding to the first liquid injection hole 304.

The welding lug 101 is provided with a strip-shaped bending hole 103 at the bending position, and the side wall of the welding lug 101 is provided with a semicircular bending hole 102 corresponding to the strip-shaped bending hole 103;

a positioning column 205 is fixedly arranged on the insulating piece 2, a positioning hole II 108 matched with the positioning column 205 is formed in the welding lug 101, and the positioning column 205 is arranged on the inner side of the positioning hole II 108.

The number of the strip-shaped bending holes 103 is two, two reinforcing ribs I104 which are arranged along the length direction of the welding lug 101 are arranged between the two strip-shaped bending holes 103, and the reinforcing ribs I104 are formed by stamping. The combined action of the strip-shaped bending holes 103, the first reinforcing ribs 104 and the semicircular bending holes 102 is convenient for the welding lug 101 to bend according to the expected positions, and in addition, when the current is overlarge, the welding lug 101 is convenient for fusing from the narrower connecting positions corresponding to the strip-shaped bending holes 103, so that the battery protection function is achieved.

The current collector 1 is provided with a second reinforcing rib 106 in a shape of a Chinese character 'mi', the second reinforcing rib 106 is formed by stamping, the current collector 1 is provided with a second liquid-permeable hole 107, and the current collector 1 is provided with a third liquid injection hole 105 corresponding to the second liquid injection hole 109. The second reinforcing rib 106 in the shape of a Chinese character 'mi' is mainly used for enhancing the structural strength of the current collector 1, the punched grooves are convenient to be completely attached to the battery cells, the welding overcurrent area is increased, and meanwhile, the third liquid injection holes 105 in the shape of a fan are formed in the disc, so that electrolyte can be conveniently and rapidly infiltrated into the battery cells.

In some embodiments, the cover plate 3 is provided with a first explosion-proof hole 303, the end surface of the cover plate 3 adjacent to the current collector 1 is provided with an explosion-proof counter bore corresponding to the first explosion-proof hole 303, an explosion-proof sheet 4 is arranged in the explosion-proof counter bore, the explosion-proof sheet 4 seals the first explosion-proof hole 303, and the explosion-proof sheet 4 is welded with the bottom end of the explosion-proof counter bore;

the insulator 2 is provided with explosion-proof holes two 206 corresponding to the explosion-proof holes one 303, the number of the explosion-proof holes two 206 is multiple, and the diameter of the explosion-proof holes two 206 is smaller than that of the explosion-proof holes one 303. The explosion-proof sheet 4 is prevented from being damaged when the welding lug 101 is bent, and the explosion-proof sheet 4 is protected.

In some embodiments, the explosion-proof sheet 4 and the cover plate 3 are integrally stamped, so that the gas generated by the battery can be conveniently and rapidly decompressed, and the safety effect is achieved.

The working process comprises the following steps:

when this scheme is implemented, first with explosion-proof piece 4 and apron 3 welding, then place insulating part 2, last with welding lug 101 and apron 3 welding, then with electric core welding of electric current collector 1, buckle welding lug 101 makes electric current collector 1 get into in the positioning groove, then put into battery case with electric core and positioning boss one 301, last welding apron 3 and battery case.

The concentricity of the electric core and the cover plate 3 is conveniently adjusted by bending the welding lug 101;

the first liquid injection hole 304 of the cover plate 3 is centered, so that the equipment investment cost of mechanisms such as CCD detection, rotary positioning and the like of manufacturing equipment is reduced, and the device has an explosion-proof valve function, can perform quick pressure relief, and ensures safety;

the current collector 1 of the cover plate component is welded with the positive electrode of the battery core and assembled into the battery, so that the polarity of the battery core can be led to the same side, the design and welding of a busbar of the battery are facilitated when the battery forms a module or a system, as the side of the positive electrode cover plate 3 is provided with the liquid injection hole and the explosion-proof piece 4, the cover plate 3 does not need to be provided with the liquid injection hole and the explosion-proof structure, and the battery does not need to be rotationally aligned when the battery forms the module or the system, so that the battery can be directly connected, and the equipment investment is saved;

the current collector 1 is provided with the welding lug 101, so that the welding yield of the battery cell and the current collector 1 is ensured, and meanwhile, the welding quality can be better detected;

the mode that the welding lug 101 is directly welded on the cover plate 3 does not need to rivet the pole of the cover plate 3, so that the cost of structural members such as rivet parts is reduced;

the insulating piece 2 is designed to facilitate bending of the welding lug 101 and radial positioning of the current collector 1, and can elastically compress the battery core of the current collector 1 after assembly, so that the absorption of the height tolerance of the winding core is good, and the self-adaption is high.

Embodiment two:

another aspect of the present utility model provides a secondary battery characterized in that: the battery comprises a battery shell, an electric core and a cover plate assembly, wherein the cover plate assembly is used for the secondary battery in the first embodiment.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present utility model, and not for limiting the same; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the utility model, and are intended to be included within the scope of the claims and description.

The foregoing description of the preferred embodiments of the utility model is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the utility model.

Claims

1. A cap assembly for a secondary battery, comprising:

the current collector comprises a current collector body (1), wherein the side wall of the current collector body (1) extends outwards to form a welding lug (101), and the welding lug (101) can be bent;

the welding lug (101) is connected with the cover plate (3);

an insulator (2), wherein the insulator (2) is arranged between the current collector (1) and the cover plate (3);

when the welding lug (101) is in a bending state, the current collector (1) corresponds to the cover plate (3).

2. The cap assembly for a secondary battery according to claim 1, wherein: a plurality of supporting bosses (202) are fixedly arranged on the end face, close to the current collector (1), of the insulating piece (2), positioning grooves are formed between the adjacent supporting bosses (202), and the width of each positioning groove is matched with the width of each welding lug (101); the supporting boss (202) is provided with a first liquid-permeable hole (203) penetrating through the insulating piece (2);

and limiting bosses (204) corresponding to the current collector (1) are fixedly arranged on the supporting bosses (202), limiting grooves are formed among the limiting bosses (204), and when the welding lugs (101) are in a bending state, the current collector (1) is arranged on the inner sides of the limiting grooves.

3. The cap assembly for a secondary battery according to claim 1, wherein: a first positioning boss (301) is fixedly arranged on the end face, close to the battery shell, of the cover plate (3), and the outer diameter of the first positioning boss (301) is matched with the inner diameter of the battery shell;

a second positioning boss (302) is fixedly arranged on the end face, close to the battery shell, of the first positioning boss (301), and the outer side edge, close to one end of the welding lug (101), of the second positioning boss (302) adopts a chamfering structure;

the insulating piece (2) is provided with a first positioning hole (201) matched with a second positioning boss (302), and the second positioning boss (302) is arranged on the inner side of the first positioning hole (201).

4. A cap assembly for a secondary battery according to claim 3, wherein: the end face, far away from the cover plate (3), of the welding lug (101) is provided with a welding groove corresponding to the second positioning boss (302), and the welding lug (101) is welded with the cover plate (3) at the position of the welding groove.

5. A cap assembly for a secondary battery according to claim 3, wherein: a first liquid injection hole (304) penetrating through the cover plate (3) is formed in the first positioning boss (301), and the first liquid injection hole (304) and the cover plate (3) are coaxially arranged;

a liquid injection counter bore (305) corresponding to the first liquid injection hole (304) is formed in the end face, far away from the current collector (1), of the cover plate (3);

and a second liquid injection hole (109) corresponding to the first liquid injection hole (304) is formed in the welding lug (101).

6. The cap assembly for a secondary battery according to claim 2, wherein: the welding lug (101) is provided with a strip-shaped bending hole (103) at the bending position, and the side wall of the welding lug (101) is provided with a semicircular bending hole (102) corresponding to the strip-shaped bending hole (103);

the welding device is characterized in that a positioning column (205) is fixedly arranged on the insulating piece (2), a positioning hole II (108) matched with the positioning column (205) is formed in the welding lug (101), and the positioning column (205) is arranged on the inner side of the positioning hole II (108).

7. The cap assembly for a secondary battery according to claim 6, wherein: the number of the strip-shaped bending holes (103) is two, reinforcing ribs I (104) arranged along the length direction of the welding lug (101) are arranged between the two strip-shaped bending holes (103), and the reinforcing ribs I (104) are formed by stamping.

8. The cap assembly for a secondary battery according to claim 6, wherein: the novel solar cell is characterized in that the current collector (1) is provided with a second reinforcing rib (106) in a shape of a Chinese character 'mi', the second reinforcing rib (106) is formed by stamping, the current collector (1) is provided with a second liquid-permeable hole (107), and the current collector (1) is provided with a third liquid-injecting hole (105) corresponding to the second liquid-injecting hole (109).

9. The cap assembly for a secondary battery according to claim 1, wherein: the explosion-proof device comprises a cover plate (3), wherein an explosion-proof hole I (303) is formed in the cover plate (3), an explosion-proof counter bore corresponding to the explosion-proof hole I (303) is formed in the end face, close to a current collector (1), of the cover plate (3), an explosion-proof sheet (4) is arranged in the explosion-proof counter bore, the explosion-proof sheet (4) seals the explosion-proof hole I (303), and the explosion-proof sheet (4) is welded with the bottom end of the explosion-proof counter bore;

and the insulating piece (2) is provided with a second explosion-proof hole (206) corresponding to the first explosion-proof hole (303).

10. A secondary battery characterized in that: comprising a battery case, a battery core, and a cap assembly for the secondary battery according to any one of claims 1 to 9.