CN219959342U

CN219959342U - Battery cell

Info

Publication number: CN219959342U
Application number: CN202320183051.7U
Authority: CN
Inventors: 周勇; 赵幸一
Original assignee: China Lithium Battery Technology Co Ltd
Current assignee: China Lithium Battery Technology Co Ltd
Priority date: 2023-02-10
Filing date: 2023-02-10
Publication date: 2023-11-03
Anticipated expiration: 2033-02-10

Abstract

The utility model relates to the technical field of batteries, and provides a battery, which comprises: a battery case; the battery cell is arranged in the battery shell and comprises a battery cell main body and a tab, and the tab is led out from the battery cell main body; the pole is arranged on the battery shell, the pole is welded with the pole lug, a connecting welding mark is formed on the pole lug, the area of the connecting welding mark is a, the area of the periphery of one side of the pole lug welded with the pole lug is b, and the area of the periphery is 0.01-0.98, so that the reliable welding area is formed between the pole lug and the pole lug, the connection strength between the pole lug and the pole lug is ensured, the overcurrent capacity between the pole lug and the pole lug is further ensured, the excessive increase of welding energy and welding time due to the excessive increase of the area of the connecting welding mark is avoided, and the excessive increase of cost due to the excessive pole column area is also avoided, thereby improving the service performance of the battery.

Description

Battery cell

Technical Field

The utility model relates to the technical field of batteries, in particular to a battery.

Background

In the related art, the battery comprises a battery core and a pole, and a pole lug of the battery core is electrically connected with the pole, so that the overcurrent capacity between the pole lug and the pole is difficult to ensure due to the connection limitation of the pole lug and the pole.

Disclosure of Invention

The utility model provides a battery, which is used for improving the service performance of the battery.

The present utility model provides a battery comprising:

a battery case;

the battery cell is arranged in the battery shell and comprises a battery cell main body and a tab, and the tab is led out from the battery cell main body;

the pole is arranged on the battery shell, the pole is welded with the pole lug to form a connecting welding mark on the pole lug, the area of the connecting welding mark is a, and the area surrounded by the circumferential outer edge of one side of the pole lug welded with the pole lug is b, and a/b is more than or equal to 0.01 and less than or equal to 0.98.

The battery provided by the embodiment of the utility model comprises a battery shell, a battery core and a pole, wherein the battery core is arranged in the battery shell, the pole is arranged on the battery shell, and the pole is welded with the pole lug. The area of the connection welding mark formed by the pole and the pole lug is a, the area formed by the circumferential outer edge of one side of the welding of the pole and the pole lug is b, and 0.01 is less than or equal to a/b is less than or equal to 0.98, so that the reliable welding area is formed between the pole and the pole lug, the connection strength between the pole and the pole lug is ensured, the overcurrent capacity between the pole and the pole lug is further ensured, the increase of welding energy and welding time due to the overlarge area of the connection welding mark can be avoided, the increase of cost due to the overlarge area of the pole lug can be avoided, and the service performance of the battery is improved.

Drawings

For a better understanding of the present disclosure, reference may be made to the embodiments illustrated in the following drawings. The components in the drawings are not necessarily to scale and related elements may be omitted in order to emphasize and clearly illustrate the technical features of the present disclosure. In addition, the relevant elements or components may have different arrangements as known in the art. Furthermore, in the drawings, like reference numerals designate identical or similar parts throughout the several views.

Wherein:

fig. 1 is a schematic view showing a structure of a battery according to an exemplary embodiment;

fig. 2 is a partial schematic structure of a battery according to an exemplary embodiment;

fig. 3 is an assembled state structure diagram of a battery according to an exemplary embodiment.

The reference numerals are explained as follows:

1. sub-welding; 10. a battery case; 11. a housing member; 12. a cover plate; 20. a battery cell; 21. a cell body; 22. a tab; 30. a pole; 40. connecting and welding; 50. and (5) pre-welding and printing.

Detailed Description

The technical solutions in the exemplary embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings in the exemplary embodiments of the present disclosure. The example embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the present disclosure, and it is therefore to be understood that various modifications and changes may be made to the example embodiments without departing from the scope of the present disclosure.

In the description of the present disclosure, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance unless explicitly specified or limited otherwise; the term "plurality" refers to two or more than two; the term "and/or" includes any and all combinations of one or more of the associated listed items. In particular, references to "the/the" object or "an" object are likewise intended to mean one of a possible plurality of such objects.

Unless specified or indicated otherwise, the terms "connected," "fixed," and the like are to be construed broadly and are, for example, capable of being fixedly connected, detachably connected, or integrally connected, electrically connected, or signally connected; "coupled" may be directly coupled or indirectly coupled through intermediaries. The specific meaning of the terms in the present disclosure may be understood by those skilled in the art according to the specific circumstances.

Further, in the description of the present disclosure, it should be understood that the terms "upper", "lower", "inner", "outer", and the like, as described in the example embodiments of the present disclosure, are described with the angles shown in the drawings, and should not be construed as limiting the example embodiments of the present disclosure. It will also be understood that in the context of an element or feature being connected to another element(s) "upper," "lower," or "inner," "outer," it can be directly connected to the other element(s) "upper," "lower," or "inner," "outer," or indirectly connected to the other element(s) "upper," "lower," or "inner," "outer" via intervening elements.

An embodiment of the present utility model provides a battery, please refer to fig. 1 to 3, including: a battery case 10; the battery cell 20, the battery cell 20 is set up in battery case 10, the battery cell 20 includes the body 21 of the battery cell and electrode lug 22, the electrode lug 22 is drawn out by body 21 of the battery cell; the pole 30, the pole 30 is set on the battery shell 10, the pole 30 is welded with the pole lug 22 to form a connection welding mark 40 on the pole lug 22, the area of the connection welding mark 40 is a, and the area of the periphery of the side, where the pole 30 is welded with the pole lug 22, is b, and a/b is more than or equal to 0.01 and less than or equal to 0.98.

The battery according to one embodiment of the utility model comprises a battery shell 10, a battery core 20 and a pole post 30, wherein the battery core 20 is arranged in the battery shell 10, the pole post 30 is arranged on the battery shell 10, and the pole post 30 is welded with the pole lug 22. The area of the connection welding mark 40 formed by the pole 30 and the pole lug 22 is a, the area formed by the circumferential periphery of one side of the pole 30 welded with the pole lug 22 is b, and 0.01-0.98 is less than or equal to a/b, so that the reliable welding area is formed between the pole 30 and the pole lug 22, the connection strength between the pole 30 and the pole lug 22 is ensured, the overcurrent capacity between the pole 30 and the pole lug 22 is further ensured, the increase of welding energy and welding time caused by the overlarge area of the connection welding mark 40 is avoided, and the increase of cost caused by the overlarge area of the pole 30 is also avoided, thereby improving the service performance of the battery.

It should be noted that, the electrode post 30 is welded with the tab 22, so that the electrical connection between the battery core 20 and the electrode post 30 is realized, and the electrode post 30 is used as an electrode lead-out terminal of the battery. In the welding process of the pole 30 and the tab 22, the connection welding mark 40 is formed on the tab 22, at this time, the pole 30 and the tab 22 form a reliable fixed connection, and the welding area between the pole 30 and the tab 22 can control the overcurrent capability between the pole 30 and the tab 22, so that it is necessary to ensure a relatively reliable welding area between the pole 30 and the tab 22. When the connection pad 40 on the tab 22 is too large, for example, the area of the connection pad 40 on the tab 22 is larger than the area surrounded by the circumferential outer edge of the side where the tab 30 and the tab 22 are welded, at this time, only a part of the connection pad 40 is formed on the tab 22 in the welding process, and the part of the connection pad 40 cannot connect the tab 22 and the tab 30, at this time, not only the welding energy is wasted, the welding time is increased, but also other structures may be damaged, for example, the insulation structure around the tab 30 may be damaged, so that the connection pad 40 on the tab 22 cannot be too large.

If the ratio of the area of the connection pad 40 to the area surrounded by the circumferential outer edge of the side where the tab 22 is welded to the terminal post 30 is too large, the connection pad 40 is too close to the insulating structure or the like of the circumferential outer edge of the terminal post 30, and the slag is liable to splash, which affects the performance of the insulating structure. If the ratio of the area of the connection solder 40 to the area surrounded by the circumferential outer edge of the side where the tab 30 and the tab 22 are welded is too small, it is difficult to ensure the overcurrent capability between the tab 30 and the tab 22, and the area of the tab 30 is wasted, which increases the battery cost to some extent. In the present embodiment, however, the above-mentioned risk can be effectively reduced by making the ratio of the area of the connection pad 40 to the area surrounded by the circumferential outer edge of the side where the tab 30 and the tab 22 are welded between 0.01 and 0.98.

The area surrounded by the circumferential outer edge of the side where the tab 30 and the tab 22 are welded, that is, the area surrounded by the circumferential edge line of the end face where the tab 30 and the tab 22 are connected, for example, when the tab 30 is a cylinder, the area surrounded by the circumferential outer edge of the side where the tab 30 and the tab 22 are welded can be regarded as the area of the end face of the tab 30; alternatively, the end surface of the pole 30 where the tab 22 is connected is a circular surface, but the circular surface has a groove, and in this case, the area surrounded by the circumferential outer edge of the side where the pole 30 is welded to the tab 22 may be regarded as the area surrounded by the circumferential outer edge of the circular surface.

Referring to fig. 3, the area surrounded by the circumferential outer edge of the side where the tab 30 is welded to the tab 22 may be the area surrounded by the circumferential outer edge of the tab 30 shown in the drawing, and the area of the connection pad 40 may be the sum of the areas of the two sub-pads 1.

In one embodiment, 0.2 is less than or equal to a/b is less than or equal to 0.7, namely, the ratio of the area of the connection welding mark 40 to the area surrounded by the circumferential outer edge of the side where the pole 30 and the pole lug 22 are welded is between 0.2 and 0.7, so that the reliable overcurrent area between the pole 30 and the pole lug 22 can be ensured, the connection strength between the pole 30 and the pole lug 22 can be ensured, and the problem that other structures are influenced by the overlarge area of the connection welding mark 40 or the cost is too high due to the overlarge area of the pole 30 can be avoided.

In one embodiment, the ratio of the area of the connection weld 40 to the area of the circumferential outer edge of the side of the tab 22 to which the tab 30 is welded may be 0.01, 0.02, 0.03, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.4, 0.5, 0.55, 0.6, 0.65, 0.68, 0.7, 0.73, 0.75, 0.8, 0.85, 0.9, 0.95, 0.97, or 0.98, etc.

In one embodiment, 1mm ² ≤a≤300mm ² I.e. the area of the connecting solder 40 may be 1mm ² -300mm ² In between, not only the overcurrent capability between the post 30 and the tab 22 can be ensured, but also the increase in welding time and battery manufacturing cost can be avoided.

The area a of the connection pads 40 may be 1mm ² 、2mm ² 、5mm ² 、10mm ² 、12mm ² 、15mm ² 、20mm ² 、25mm ² 、30mm ² 、40mm ² 、45mm ² 、50mm ² 、55mm ² 、60mm ² 、70mm ² 、75mm ² 、80mm ² 、90mm ² 、95mm ² 、100mm ² 、110mm ² 、120mm ² 、130mm ² 、140mm ² 、150mm ² 、180mm ² 、200mm ² 、210mm ² 、220mm ² 、230mm ² 、240mm ² 、250mm ² 、260mm ² 、270mm ² 、280mm ² 、285mm ² 、290mm ² 、295mm ² Or 300mm ² Etc.

In one embodiment, the post 30 and the tab 22 may be connected by a tab, at which point the post 30 may be welded to the tab and the tab 22 may be welded to the tab, thereby facilitating electrical connection of the post 30 to the tab 22.

In one embodiment, the post 30 and tab 22 may be connected by conductive glue.

In one embodiment, as shown in fig. 2, the tab 30 is directly welded with the tab 22, so that the number of components of the battery can be reduced, thereby simplifying the structure of the battery, and the weight of the battery can be reduced, and the capacity density of the battery can be improved to some extent.

In one embodiment, the tab 22 includes a plurality of single-piece tabs, the single-piece tabs are welded to form the pre-welding seal 50, the connection welding seal 40 covers the pre-welding seal 50, that is, the pre-welding seal 50 may be formed by directly pre-welding the tab 22, that is, the tab 22 is pre-welded before the tab 22 is welded with the post 30, so that the plurality of single-piece tabs of the tab 22 are combined together, the structural strength of the tab 22 is improved to a certain extent, and the strength of the tab 22 is higher when all single-piece tabs of the tab 22 are combined together, so that when the tab 22 and the post 30 are welded, even if the welding energy is relatively larger, the connection welding seal 40 is performed on the basis of the pre-welding seal 50, the pre-welding seal 50 enhances the strength of the tab 22, thereby greatly reducing the probability of damage to the tab 22 during secondary welding.

As shown in connection with fig. 3, the connection pad 40 is disposed overlying the pre-pad 50.

A portion of the connection pad 40 may be located on the pre-bonding pad 50, or the entirety of the connection pad 40 may be located on the pre-bonding pad 50. The connection pad 40 may cover a portion of the pre-bonding pad 50, or the connection pad 40 may cover all of the pre-bonding pad 50. In one embodiment, the pre-bonding pad 50 and the bonding pad 40 are formed sequentially, i.e., the bonding pad 40 is formed in such a manner that damage to the tab 22 is avoided because the pre-bonding pad 50 enhances the strength of the tab 22 even though the bonding energy is relatively large due to the pre-bonding pad 50.

In one embodiment, the pre-solder 50 and the link 40 are formed by different soldering means, the pre-solder 50 and the link 40 being both laser solder; or, the pre-bonding pad 50 and the connection pad 40 are both ultrasonic pads; or, the pre-bonding pad 50 is an ultrasonic pad, and the connecting pad 40 is a laser pad; alternatively, the pre-bonding pad 50 is a laser pad and the bonding pad 40 is an ultrasonic pad.

Specifically, the first welding forms the pre-welding stamp 50, the second welding forms the connecting stamp 40, and the first welding may be any one of ultrasonic welding and laser welding. Accordingly, any one of ultrasonic welding and laser welding can be adopted for the second welding mode, so long as the stability of connection can be ensured, and the tab 22 cannot be damaged during the first welding.

In one embodiment, the attachment weld 40 is located in the middle of the pre-weld 50 to ensure that the tab 22 is not damaged during the second weld.

It should be noted that the central portion is not specifically defined as the central portion, but is rather located in the central portion of the pre-solder pad 50 with respect to the peripheral outer edge of the pre-solder pad 50, i.e., the connection pad 40 does not intersect the peripheral outer edge of the pre-solder pad 50.

In an embodiment, the orthographic projection of the connection welding mark 40 towards the pole 30 is located in the middle of the pole 30, so that the welding connection position of the pole lug 22 and the pole 30 is located in the middle of the pole 30, the connection strength of the pole lug 22 and the pole 30 can be ensured, the overcurrent capacity between the pole lug 22 and the pole 30 is further ensured, the heat generated in the welding process can be prevented from affecting other structures around the pole 30, and the safety performance of the battery can be improved to a certain extent.

It should be noted that, the central portion is not specifically defined as the central position, but is rather located in the central portion of the pole 30 with respect to the circumferential outer edge of the pole 30, that is, the orthographic projection of the connection pad 40 toward the pole 30 does not intersect the circumferential outer edge of the pole 30.

In some embodiments, it is not excluded that part of the connecting solder 40 may be located outside the pre-soldering solder 50, or that the edges of the connecting solder 40 may coincide with the edges of the pre-soldering solder 50.

In one embodiment, the distance between the orthographic projection of the connection weld 40 toward the post 30 and the circumferential outer edge of the post 30 is 1mm-30mm, not only ensuring overcurrent capability between the tab 22 and the post 30, but also avoiding the influence of the welding capability on other parts around the post 30, for example, on the insulating structure, and further, on the lower insulator of the battery.

The distance between the orthographic projection of the connection weld 40 toward the post 30 and the circumferential outer edge of the post 30 may be 1mm, 1.5mm, 2mm, 2.3mm, 2.5mm, 3mm, 5mm, 5.5mm, 6mm, 7mm, 8mm, 9mm, 9.5mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 18mm, 19mm, 20mm, 21mm, 22mm, 23mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, or the like.

As shown in connection with fig. 3, the distance between the orthographic projection of the connection weld 40 toward the pole shank 30 and the circumferential outer edge of the pole shank 30 may be expressed as h, which ranges from 1mm to 30mm.

In one embodiment, as shown in fig. 3, the connection solder marks 40 include at least two sub solder marks 1 arranged at intervals, so that not only can the connection strength between the tab 22 and the pole 30 be ensured, but also the overcurrent capability between the tab 22 and the pole 30 can be ensured, and the tab 22 and the pole 30 can be conveniently welded, and the tab 22 is prevented from being damaged due to overlarge heat generation caused by continuous welding.

It should be noted that in some embodiments, the connection pad 40 may be an integral pad.

In one embodiment, as shown in fig. 1, the battery case 10 includes a case member 11 and a cover plate 12, the case member 11 is formed with an accommodating space, the cover plate 12 is a flat plate, and the post 30 is disposed on the cover plate 12, so that the disposition of the post 30 can be facilitated, the connection of the post 30 with the tab 22 can also be facilitated, and the mounting of the battery cell 20 into the accommodating space of the case member 11 can also be facilitated when the connection of the post 30 and the tab 22 is formed.

The pole 30 is disposed on the cover plate 12, and the cover plate 12 is a flat plate, so that when the pole 30 is welded with the tab 22, the welding of the pole 30 and the tab 22 can be prevented from being affected by other structures, and after the pole 30 is connected with the tab 22, the battery cell 20 can be mounted in the accommodating space of the housing member 11, and the connection between the cover plate 12 and the housing member 11 is completed.

The case member 11 and the cover plate 12 may be provided independently, and the case member 11 and the cover plate 12 may be welded. In some embodiments, it is not excluded that the housing part 11 and the cover plate 12 may be of one unitary structure, the receiving space for the battery cells 20 being formed by stamping, and subsequently being closed by welding.

The casing 11 may have a structure with one closed end, where the cover 12 may be provided with two polar posts 30, and the two polar posts 30 may be respectively connected with two polar ears 22 of the electric core 20, and where the two polar ears 22 of the electric core 20 may be respectively a positive polar ear and a negative polar ear; alternatively, the housing member 11 may include a cover plate and a housing having both ends open, and in this case, the opposite cover plates may be provided with the poles 30, respectively. The specific structure of the housing member 11 is not limited.

The battery includes a cell and an electrolyte, and is a minimum unit capable of performing an electrochemical reaction such as charge/discharge. The battery cell refers to a unit formed by winding or laminating a stacked portion, wherein the stacked portion comprises a first pole piece, a separator and a second pole piece. When the first pole piece is a positive pole piece, the second pole piece is a negative pole piece. Wherein the polarities of the first pole piece and the second pole piece can be interchanged. The first and second pole pieces are coated with an active substance.

In one embodiment, the battery may be a square battery, that is, the battery may be a quadrangular battery, where the quadrangular battery mainly refers to a prismatic shape, but it is not strictly limited whether each side of the prism is necessarily a strictly defined straight line, and corners between sides are not necessarily right angles, and may be arc transitions.

The battery can be a laminated battery, so that the battery is not only convenient to group, but also long in length. Specifically, the battery cell is a laminated battery cell, and the battery cell is provided with a first pole piece, a second pole piece opposite to the first pole piece and a diaphragm sheet arranged between the first pole piece and the second pole piece, which are mutually laminated, so that a plurality of pairs of the first pole piece and the second pole piece are stacked to form the laminated battery cell.

Alternatively, the battery may be a wound battery in which a first pole piece, a second pole piece opposite in electrical property to the first pole piece, and a separator sheet disposed between the first pole piece and the second pole piece are wound to obtain a wound battery cell.

An embodiment of the present utility model also provides a battery pack including the above battery.

The battery pack according to one embodiment of the present utility model includes a battery, the battery includes a battery case 10, a battery cell 20, and a post 30, the battery cell 20 is disposed in the battery case 10, the post 30 is disposed on the battery case 10, and the post 30 is welded with the tab 22. The area of the connection welding mark 40 formed by the pole 30 and the pole lug 22 is a, the area formed by the circumferential periphery of one side where the pole 30 and the pole lug 22 are welded is b, and 0.01-0.98 is less than or equal to a/b, so that a reliable welding area is formed between the pole 30 and the pole lug 22, the connection strength between the pole 30 and the pole lug 22 is ensured, the overcurrent capacity between the pole 30 and the pole lug 22 is further ensured, the increase of welding energy and welding time caused by the overlarge area of the connection welding mark 40 is avoided, and the increase of cost caused by the overlarge area of the pole 30 is also avoided, thereby improving the service performance of the battery pack.

In one embodiment, the battery pack is a battery module or a battery pack.

The battery module includes a plurality of batteries, and the battery can be square battery, and the battery module can also include end plate and curb plate, and end plate and curb plate are used for fixed a plurality of batteries.

The battery pack comprises a plurality of batteries and a box body, wherein the box body is used for fixing the plurality of batteries.

It should be noted that the battery pack includes a plurality of batteries, and a plurality of batteries are disposed in the case. Wherein, a plurality of batteries can be installed in the box after forming the battery module. Or, a plurality of batteries can be directly arranged in the box body, namely, the plurality of batteries do not need to be grouped, and the plurality of batteries are fixed by the box body.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the utility model disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the utility model following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. The specification and example embodiments are to be considered exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It is to be understood that the present disclosure is not limited to the precise arrangements and instrumentalities shown in the drawings, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A battery, comprising:

a battery case (10);

the battery cell (20), the battery cell (20) is arranged in the battery shell (10), the battery cell (20) comprises a battery cell main body (21) and a tab (22), and the tab (22) is led out from the battery cell main body (21);

the electrode post (30), electrode post (30) set up in on battery case (10), electrode post (30) with utmost point ear (22) welding is in order to form on utmost point ear (22) and connect welded seal (40), the area of connecting welded seal (40) is a, the area that utmost point post (30) with the circumference peripheral edge of utmost point ear (22) welded one side encloses is b, and 0.01 is less than or equal to a/b is less than or equal to 0.98.

2. The battery of claim 1, wherein 0.2 +.a/b +.0.7.

3. The battery of claim 1, wherein 1mm ² ≤a≤300mm ² 。

4. The battery according to claim 1, characterized in that the pole (30) is welded directly to the tab (22).

5. The battery of claim 1, wherein the tab (22) comprises a plurality of individual tabs welded to form a pre-weld (50), the connection weld (40) overlying the pre-weld (50);

wherein the pre-bonding pad (50) and the connection pad (40) are sequentially formed.

6. The battery according to claim 5, characterized in that the connection pad (40) is located in the middle of the pre-pad (50).

7. The battery according to claim 1, characterized in that the orthographic projection of the connection weld (40) towards the post (30) is located in the middle of the post (30).

8. The battery according to claim 7, characterized in that the distance between the orthographic projection of the connection weld (40) towards the pole (30) and the circumferential outer edge of the pole (30) is 1mm-30mm.

9. The battery according to claim 1, characterized in that the connection solder (40) comprises at least two sub-solder (1) arranged at intervals.

10. The battery according to claim 1, wherein the battery case (10) includes a case member (11) and a cover plate (12), the case member (11) is formed with an accommodation space, the cover plate (12) is a flat plate, and the post (30) is provided on the cover plate (12).

11. The battery of claim 1, wherein the battery is a quadrangular type battery.