CN215578946U

CN215578946U - Connecting device for battery and battery pack

Info

Publication number: CN215578946U
Application number: CN202121238743.4U
Authority: CN
Inventors: 蒋世用; 詹世英; 徐德雷; 李海军; 程阿鸿; 邓赛君
Original assignee: Yinlong New Energy Co Ltd
Current assignee: Yinlong New Energy Co Ltd
Priority date: 2021-06-03
Filing date: 2021-06-03
Publication date: 2022-01-18
Anticipated expiration: 2031-06-03

Abstract

The utility model provides a connecting device for a battery and a battery pack assembly. The battery connecting device includes: the connecting structure comprises a first connecting piece and a second connecting piece which are connected, an included angle is formed between the first connecting piece and the second connecting piece, the battery comprises a battery cover plate and a battery core, the first connecting piece is used for being electrically connected with the battery cover plate of the battery, and the second connecting piece is used for being electrically connected with a lug of the battery core; and the locking structure comprises a locking member fixedly connected with the second connecting member so as to lock the lug on the second connecting member. The technical scheme of the utility model solves the problems that the second connecting piece of the connecting device for the battery in the prior art is easy to generate explosion points, leakage welding or insufficient welding and the like when being welded with the lug in the subsequent process.

Description

Connecting device for battery and battery pack

Technical Field

The utility model relates to the technical field of lithium ion batteries, in particular to a connecting device for a battery and a battery core assembly.

Background

With the continuous development of new energy industry, the application of lithium ion batteries is also more and more extensive, for example, lithium ion batteries are generally used in digital products, electric vehicles and energy storage and charging systems. The lithium ion battery consists of a shell, a battery cell, electrolyte and other auxiliary connecting pieces. The connecting piece for the battery is a connecting part for connecting the battery core and the battery cover plate, and plays a role in conductive connection in the whole battery.

In the prior art, the battery core and the battery cover plate are generally connected by a flexible connection structure, and the flexible connection structure generally consists of one or more layers of thin conductive thin plates with different shapes. The one end of the flexible connection is directly welded with the tab of the battery core, the other end of the flexible connection is directly welded with the pole of the battery cover plate, although a closed conductive path can be formed inside the battery, the flexible connection structure is directly welded with the tab of the battery core, and the problems of spot explosion, welding leakage, cold welding and the like easily occur.

SUMMERY OF THE UTILITY MODEL

The utility model mainly aims to provide a connecting device for a battery and a battery core assembly, which solve the problems that a second connecting piece of the connecting device for the battery in the prior art is easy to generate explosion points, missing welding or insufficient welding and the like during subsequent welding with a lug.

In order to achieve the above object, according to an aspect of the present invention, there is provided a connection device for a battery, including: the connecting structure comprises a first connecting piece and a second connecting piece which are connected, an included angle is formed between the first connecting piece and the second connecting piece, the battery comprises a battery cover plate and a battery core, the first connecting piece is used for being electrically connected with the battery cover plate of the battery, and the second connecting piece is used for being electrically connected with a lug of the battery core; and the locking structure comprises a locking member fixedly connected with the second connecting member so as to lock the lug on the second connecting member.

Furthermore, at least one side of the second connecting piece is provided with a groove for mounting a lug; or, the first connecting piece and the second connecting piece both comprise conductive pieces with preset thicknesses.

Furthermore, a mounting hole is formed in the second connecting piece, a first assembling through hole corresponding to the mounting hole is formed in the tab, and the locking piece penetrates through the first assembling through hole and then is connected with the mounting hole.

Furthermore, the locking structure further comprises a clamping plate, a second assembling through hole corresponding to the mounting hole is formed in the clamping plate, and part of the locking part penetrates through the second assembling through hole and the first assembling through hole and then is riveted or connected with the mounting hole in a threaded mode.

Further, the connection structure further comprises a connection groove arranged in the first connection member, and the connection groove is located on one side of the first connection member, which faces the battery cell.

Further, the locking member comprises a locking body and an end cap connected with the locking body, the diameter of the locking body is smaller than that of the end cap, a first step surface is arranged between the locking body and the end cap, and the locking body is connected with the mounting hole.

Further, the second assembling through hole comprises a first hole section and a second hole section which are communicated, the diameter of the first hole section is smaller than that of the second hole section, a second step surface is arranged between the first hole section and the second hole section, and the first step surface is abutted to the second step surface.

According to another aspect of the utility model, the utility model provides a battery core assembly, which comprises a battery core and the connecting device for the battery.

Furthermore, the battery core comprises a core and two tabs connected with the core, the battery core assembly comprises two battery connecting devices correspondingly arranged with the two tabs, and each tab is connected with a corresponding second connecting piece through a locking structure.

Furthermore, the electric core assembly comprises two electric cores, two opposite sides of the second connecting piece are provided with grooves, the two grooves correspond to the two electric cores, and the electrode lugs of the electric cores are connected with the second connecting piece through a locking structure.

By applying the technical scheme of the utility model, the connecting structure and the locking structure are arranged, the first connecting piece of the connecting structure is connected with the battery cover plate, the second connecting piece of the connecting structure is connected with the pole ear of the battery core through the locking structure, so that the pole ear of the battery core can be connected with the pole column of the battery cover plate through the connecting device for the battery, and the locking structure can enable the second connecting piece to be tightly matched with the pole ear, so that a gap between the second connecting piece and the pole ear is avoided, and the problems that the second connecting piece is easy to have explosion points, welding leakage or insufficient welding and the like when being welded with the pole ear in the subsequent process are avoided.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the utility model and, together with the description, serve to explain the utility model and not to limit the utility model. In the drawings:

FIG. 1 shows a schematic structural diagram of an electrical core assembly of an embodiment of the present invention;

fig. 2 is an exploded view schematically showing a battery connecting device of the cell assembly of fig. 1; and

fig. 3 is a schematic view showing a connection structure of the battery connection device of fig. 2.

Wherein the figures include the following reference numerals:

10. a connecting structure; 11. a first connecting member; 12. a second connecting member; 13. a groove; 14. mounting holes; 15. connecting grooves; 20. an electric core; 22. a tab; 23. a winding core; 30. a locking structure; 31. a locking member; 311. a locking body; 312. an end cap; 32. a splint; 33. a second fitting through hole; 331. a first bore section; 332. a second bore section.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

The battery connecting device according to the embodiment of the present invention can improve the current load capacity of the battery and also improve the heat dissipation capacity of the battery.

It should be noted that the connection structure of the connection device for a battery according to the embodiment of the present invention and the tab are connected by riveting and laser welding, so that the problems of low efficiency and easy damage to the tab 22 of the battery cell 20 in the conventional ultrasonic welding can be avoided, and further, the production efficiency of the battery can be improved, thereby laying a foundation for mass production.

It should be noted that the battery core 20 and the battery cover plate of the embodiment of the utility model may adopt a battery core and a battery cover plate of a lithium titanate prismatic battery with the size of 30mm × 186mm × 94mm and the stored electric energy of 25 Ah.

The inventor knows a connection structure for adapting to the use condition of high-rate large-current charge and discharge, generally changes a single-layer flexible connection structure into a multi-layer flexible connection structure, reduces the thickness of each layer of flexible connection, increases the number of layers of the flexible connection structure, and thus can increase the over-current bearing capacity to a certain extent, but gaps exist between the layers of the multi-layer flexible connection structure, so that poor welding phenomena such as spot explosion, insufficient welding and the like can occur when the flexible connection structure is welded with a tab of a battery core and a battery cover plate; further, gaps between layers of the multi-layer flexible connection structure slow down the conduction of electrons, thereby affecting the service performance of the battery and further causing safety problems.

Thus, as shown in fig. 1, an embodiment of the present invention provides a connection device for a battery. The battery connecting device includes a connecting structure 10 and a locking structure 30. The connection structure 10 comprises a first connection piece 11 and a second connection piece 12 which are connected, an included angle is formed between the first connection piece 11 and the second connection piece 12, the battery comprises a battery cover plate and a battery cell 20, the first connection piece 11 is used for being electrically connected with the battery cover plate of the battery, and the second connection piece 12 is used for being electrically connected with a tab 22 of the battery cell 20; the locking arrangement 30 includes a locking member 31 fixedly connected to the second connector 12 to lock the tab 22 to the second connector 12.

Among the above-mentioned technical scheme, through setting up connection structure 10 and locking structure 30, and connection structure 10's first connecting piece 11 and battery cover connection, connection structure 10's second connecting piece 12 passes through locking structure 30 and is connected with electric core 20's utmost point ear 22, can make electric core 20's utmost point ear 22 pass through for the battery connecting device and battery cover's utmost point post be connected like this, and locking structure 30 can make second connecting piece 12 and utmost point ear 22 closely cooperate, avoid appearing the clearance between second connecting piece 12 and the utmost point ear 22, thereby avoid second connecting piece 12 to appear exploding some or leak welding or rosin joint scheduling problem easily when follow-up with utmost point ear 22 welding.

Preferably, in the embodiment of the present invention, the included angle between the first connecting member 11 and the second connecting member 12 is 90 °, and the first connecting member 11 and the second connecting member 12 form an L-shaped connecting structure. Of course, in an alternative embodiment not shown in the drawings, the included angle between the first connecting member 11 and the second connecting member 12 may be other angles as long as the pole of the battery cover plate and the pole ear 22 of the battery cell can be connected through the first connecting member 11 and the second connecting member 12.

It should be noted that the battery connection device according to the embodiment of the present invention is applied to a prismatic battery, and the shape of the connection structure 10 is correspondingly set to an L-shape. Of course, in an alternative embodiment not shown in the drawings, the shape of the connection structure 10 may be other shapes as long as the pole of the battery cover plate and the pole ear 22 of the battery cell can be connected.

Preferably, in the embodiment of the present invention, the first connecting member 11 and the second connecting member 12 are both block-shaped connecting members, so that the cross-sectional area of the connecting structure 10 can be increased, and thus the flow capacity of the connecting structure 10 can be increased.

Specifically, in the embodiment of the present invention, after the second connection member 12 is connected to the tab 22 through the locking member 31, the tab 22 may be welded to the second connection member 12, so that at least a portion of the second connection member 12 and the tab 22 are connected through a weld (i.e., at least a portion of the second connection member 12 and the tab 22 may form an integrated structure), thereby conducting current from the weld to the pole of the battery cover plate, and further increasing the current carrying capacity of the battery. Further, the tab 22 and the second connecting member 12 are laser welded, so that the contact area between the tab 22 and the second connecting member 12 can be reduced, and at least part of the second connecting member 12 and the tab 22 are connected by a weld (i.e. at least part of the second connecting member 12 and the tab 22 can form an integrated structure), so that the contact resistance between the second connecting member 12 and the tab 22 can be reduced, thereby reducing heat generation in the conductive process and further improving the heat dissipation capacity of the battery.

Preferably, in the embodiment of the present invention, the connection manner between the second connection member 12 and the tab 22 may be riveting, screwing, welding, or the like. This embodiment is preferably riveted and then welded.

Preferably, in the embodiment of the present invention, the welding is performed by laser welding, that is, the tab 22 of the battery cell 20 and the second connecting member 12 are welded by using a laser with a certain power.

In the embodiment of the present invention, when the length of the riveted tab 22 in the left-right direction in fig. 2 is greater than the width of the second connection member 12, the length of the tab 22 of the battery core needs to be cut to be equal to the width of the second connection member 12, and then laser welding is performed.

As shown in fig. 3, the first connection member 11 and the second connection member 12 each include a conductive member having a predetermined thickness.

Among the above-mentioned technical scheme, through setting up connection structure 10 and locking structure 30, and connection structure 10's first connecting piece 11 and battery cover connection, connection structure 10's second connecting piece 12 passes through locking structure 30 and is connected with electric core 20's utmost point ear 22, thus, can make electric core 20's utmost point ear 22 pass through the utmost point post that connecting device and battery cover were used to the battery and be connected, and first connecting piece 11 and second connecting piece 12 all including the electrically conductive piece that has preset thickness, can make the utmost point ear 22 of electric core 20 and the utmost point post of battery cover have great overcurrent area between the utmost point post, thereby the current load capacity of battery has been improved, and then the problem that the battery that adopts the flexible coupling structure among the prior art exists the current bearing capacity not enough has been solved.

Preferably, in an embodiment of the present invention, the predetermined thickness of the conductive member ranges from 3mm to 15 mm.

In an embodiment of the utility model, as shown in fig. 3, at least one side of the second connection member 12 is provided with a groove 13 for mounting a tab 22.

Through the above arrangement, the tab 22 can be installed in the groove 13, and the locking member 31 locks the tab 22 in the groove 13, so that one side of the tab 22 is tightly attached to the bottom wall of the groove 13, and thus, the current can be better guided to the second connecting member 12 through the tab 22 and then guided to the pole of the battery cover plate.

As shown in fig. 1 and 2, in the embodiment of the present invention, the second connecting member 12 is provided with a mounting hole 14, the tab 22 is provided with a first through-hole corresponding to the mounting hole 14, and the locking member 31 passes through the first through-hole and then is connected to the mounting hole 14.

With the above arrangement, the locking member 31 can lock the tab 22 to the second connection member 12 so that one side of the tab 22 is closely fitted to the bottom wall of the recess 13, thereby allowing current to flow from the tab 22 to the second connection member.

Preferably, in the embodiment of the present invention, the mounting hole 14 is punched, but of course, in an alternative embodiment not shown in the drawings, the mounting hole 14 may be a threaded hole.

In the embodiment of the present invention, as shown in fig. 2, the locking structure 30 further includes a clamping plate 32, the clamping plate 32 is provided with a second assembling through hole 33 corresponding to the mounting hole 14, and a portion of the locking member 31 passes through the second assembling through hole 33 and the first assembling through hole and is riveted or screwed with the mounting hole 14.

Among the above-mentioned technical scheme, through setting up splint 32, can compress tightly utmost point ear 22 on second connecting piece 12, and splint 32 covers utmost point ear 22, thus, retaining member 31 is used in utmost point ear 22's power more even, thereby make whole utmost point ear 22 all with second connecting piece 12 in close contact with, on the one hand, can avoid producing the clearance between utmost point ear 22 and the second connecting piece 12 like this, thereby avoid the second connecting piece appear exploding the point easily when follow-up with utmost point ear welding or leak welding or rosin joint scheduling problem, on the other hand, can increase the area of contact between utmost point ear 22 and the second connecting piece 12 like this, avoid producing the clearance between utmost point ear 22 and the second connecting piece 12, thereby make the current circulation better, increase the current carrying capacity of battery.

Specifically, in the embodiment of the present invention, at least one side of the second connecting member 12 is provided with a groove 13, and the locking structure 30 includes at least one clamping plate 32, and the clamping plate 32 is disposed corresponding to the groove 13.

Preferably, in the embodiment of the present invention, the second fitting through hole 33 is punched.

Preferably, in the embodiment of the present invention, the second fitting through hole 33, the first fitting through hole, and the mounting hole 14 are coaxially disposed.

As shown in fig. 1 and fig. 3, in the embodiment of the present invention, the connection structure 10 further includes a connection groove 15 disposed on the first connection member 11, and the connection groove 15 is located on a side of the first connection member 11 facing the battery cell 20.

Through the above setting, first connecting piece 11 can weld with the battery apron through spread groove 15, and spread groove 15 is located one side of first connecting piece 11 towards electric core 20 (the one side that deviates from the battery apron of first connecting piece 11 promptly), can guarantee zonulae occludens between first connecting piece 11 and the battery apron like this, in order to avoid first connecting piece 11 and battery apron to produce the clearance and influence welded effect, thereby avoid producing rosin joint or leaking and weld and influence the performance of battery.

As shown in fig. 2, in the embodiment of the present invention, the locker 31 includes a locker body 311 and an end cap 312 coupled to the locker body 311, the locker body 311 has a diameter smaller than that of the end cap 312, and a first step surface is formed between the locker body 311 and the end cap 312, and the locker body 311 is coupled to the mounting hole 14.

Through the above arrangement, the locking main body 311 can be connected with the mounting hole 14 of the second connecting piece 12, and the end cap 312 abuts against a part of the clamping plate 32, so that the tab 22 can be compressed between the clamping plate 32 and the second connecting piece 12 through the clamping plate 32, so as to increase the contact area between the tab 22 and the second connecting piece 12, and avoid generating a gap between the tab 22 and the second connecting piece 12, thereby avoiding the problems that the second connecting piece is easy to have a spot explosion or leakage welding or false welding and the like during subsequent welding with the tab, further, current can be better circulated, and the current carrying capacity of the battery is increased.

Preferably, in the embodiment of the present invention, the locker 31 is a rivet. Of course, in an alternative embodiment not shown in the drawings, the locking member 31 may be a fixing member such as a screw or a pin, etc. which can conduct electricity, as long as the locking member 31 can be fitted into the mounting hole 14 and lock the tab 22 and the clamping plate 32 to the second connecting member 12.

Preferably, in the embodiment of the present invention, the locking structure includes at least one set of locking members 31, and the number of sets of locking members 31 is provided corresponding to the number of tabs 22. Wherein, a set of locking members 31 may include a plurality of locking members 31, and a plurality of locking members 31 are disposed corresponding to the plurality of mounting holes 14.

As shown in fig. 2, in the embodiment of the present invention, the second through hole 33 includes a first hole section 331 and a second hole section 332 which are communicated with each other, a diameter of the first hole section 331 is smaller than a diameter of the second hole section 332, a second step surface is provided between the first hole section 331 and the second hole section 332, and the first step surface abuts against the second step surface.

With the above arrangement, the locking body 311 is coupled to the mounting hole after passing through the second hole section 332, the first hole section 331 and the first fitting through-hole, at least a portion of the end cap 312 is located in the second hole section 332, and the first step surface abuts against the second step surface, so that the locking member 31 can lock the clamping plate 32 and the tab 22 to the second connecting member 12.

According to another aspect of the present invention, as shown in fig. 1, the present invention provides an electric core assembly. The battery pack assembly comprises the battery cells 20 and the above-mentioned connecting device for the battery. The above-mentioned battery core assembly has all the advantages of the above-mentioned connecting device for battery, and its details are not described herein.

As shown in fig. 1, in the embodiment of the present invention, the battery cell 20 includes a winding core 23 and two tabs 22 connected to the winding core 23, the battery cell assembly includes two battery connection devices corresponding to the two tabs 22, and each tab 22 is connected to the corresponding second connection member 12 through a locking structure 30.

With the above arrangement, the locking structure 30 and the connecting structure 10 of one battery connecting device can connect one tab (e.g., a positive tab) with one terminal (e.g., a positive terminal) of the battery cover plate, and the locking structure 30 and the connecting structure 10 of the other battery connecting device can connect the other tab (e.g., a negative tab) with the other terminal (e.g., a negative terminal) of the battery cover plate, so as to form a conductive path.

Preferably, in the embodiment of the present invention, the tab 22 is located between the clamping plate 32 and the second connecting member 12, and the locking member 31 is connected to the mounting hole 14 of the second connecting member 12 after passing through the second assembling through-hole of the clamping plate 32 and the first assembling through-hole of the tab 22, so that the tab 22 can be locked to the second connecting member 12.

As shown in fig. 1, in the embodiment of the present invention, the cell assembly includes two cells 20, two opposite sides of the second connecting member 12 are respectively provided with a groove 13, the two grooves 13 are disposed corresponding to the two cells 20, and the tabs of the cells are connected to the second connecting member 12 through a locking structure.

Through the above arrangement, the connecting device for a battery can connect the tabs 22 of two cells with the same polarity, so that the two cells 20 can be arranged in parallel, and thus, the internal resistance of the cell assembly of the battery can be reduced to 50% of the original internal resistance, so that the cell assembly of the battery has less heat generation under the condition of the same electric quantity, and the improvement of the electrochemical performance of the battery is facilitated.

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects: through setting up connection structure and locking structure to connection structure's first connecting piece and battery cover connection, connection structure's second connecting piece passes through locking structure and is connected with the utmost point ear of electric core, can make the utmost point ear of electric core pass through for the battery connecting device and be connected with the utmost point post of battery cover like this, and locking structure can make second connecting piece and utmost point ear closely cooperate, avoid appearing the clearance between second connecting piece and the utmost point ear, thereby avoid the second connecting piece appear exploding the some easily or leak welding or rosin joint scheduling problem when follow-up with electrode welding.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A connecting device for a battery, comprising:

the connecting structure (10) comprises a first connecting piece (11) and a second connecting piece (12) which are connected, an included angle is formed between the first connecting piece (11) and the second connecting piece (12), the battery comprises a battery cover plate and a battery core (20), the first connecting piece (11) is used for being electrically connected with the battery cover plate of the battery, and the second connecting piece (12) is used for being electrically connected with a lug (22) of the battery core (20);

and the locking structure (30) comprises a locking piece (31) fixedly connected with the second connecting piece (12) so as to lock the lug (22) on the second connecting piece (12).

2. The battery connecting device according to claim 1, wherein at least one side of the second connecting member (12) is provided with a groove (13) for mounting the tab (22); or, the first connecting piece (11) and the second connecting piece (12) both comprise conductive pieces with preset thicknesses.

3. The connecting device for the battery according to claim 1, wherein the second connecting member (12) is provided with a mounting hole (14), the tab (22) is provided with a first assembling through hole corresponding to the mounting hole (14), and the locking member (31) is connected with the mounting hole (14) after passing through the first assembling through hole.

4. The battery connecting device according to claim 3, wherein the locking structure (30) further comprises a clamping plate (32), a second assembling through hole (33) corresponding to the mounting hole (14) is formed in the clamping plate (32), and a part of the locking member (31) is riveted or screwed with the mounting hole (14) after passing through the second assembling through hole (33) and the first assembling through hole.

5. The connection device for batteries according to any of claims 1 to 4, characterized in that the connection structure (10) further comprises a connection slot (15) provided to the first connection member (11), the connection slot (15) being located on a side of the first connection member (11) facing the battery cell (20).

6. The connecting device for battery according to claim 4, wherein the locker (31) comprises a locker body (311) and an end cap (312) connected to the locker body (311), the locker body (311) having a diameter smaller than that of the end cap (312) and having a first step surface between the locker body (311) and the end cap (312), the locker body (311) being connected to the mounting hole (14).

7. The battery connecting device according to claim 6, wherein the second fitting through hole (33) includes a first hole section (331) and a second hole section (332) communicating with each other, the first hole section (331) has a diameter smaller than that of the second hole section (332), and a second step surface is provided between the first hole section (331) and the second hole section (332), the first step surface abutting against the second step surface.

8. An electric core assembly, characterized in that it comprises an electric core (20) and a connection device for batteries according to any one of claims 1 to 7.

9. The battery core assembly according to claim 8, wherein the battery core (20) comprises a winding core (23) and two tabs (22) connected to the winding core (23), the battery core assembly comprises two battery connection devices corresponding to the two tabs (22), and each tab (22) is connected to the corresponding second connection member (12) through the locking structure (30).

10. The battery core assembly according to claim 8, wherein the battery core assembly comprises two battery cores (20), two grooves (13) are formed on two opposite sides of the second connecting member (12), the two grooves (13) are arranged corresponding to the two battery cores (20), and the tabs (22) of the battery cores (20) are connected with the second connecting member (12) through the locking structure (30).