CN111430653B

CN111430653B - Battery module, battery package and vehicle

Info

Publication number: CN111430653B
Application number: CN202010064748.3A
Authority: CN
Inventors: 李树人; 李佳佳; 史童男; 陈华贤
Original assignee: Svolt Energy Technology Co Ltd
Current assignee: Svolt Energy Technology Co Ltd
Priority date: 2020-01-20
Filing date: 2020-01-20
Publication date: 2022-05-27
Anticipated expiration: 2040-01-20
Also published as: CN111430653A

Abstract

The application discloses battery module, battery package and vehicle, battery module include: the battery pack comprises a plurality of battery cores, each battery core group comprises a plurality of battery cores provided with pole pieces, and the pole pieces in each battery core group are superposed to form a pole piece group; and the lug is fixedly connected with the plurality of pole piece groups. According to the battery module, all pole pieces in the battery module are divided into the plurality of pole piece groups, the pole lugs respectively weld the plurality of pole piece groups, and the condition of insufficient welding is avoided by increasing the welding area at the pole lugs; meanwhile, the overcurrent capacity of the lug can be increased, and the phenomenon that the internal resistance of the alternating current part of the battery cell is too large to influence the performance of the battery module is avoided.

Description

Battery module, battery package and vehicle

Technical Field

The application relates to the technical field of batteries, in particular to a battery module, a battery pack and a vehicle.

Background

Soft-packaged battery cell has become the key of electric automobile development on the existing market, along with the utmost point piece is more and more in the electric core group, needs very accurate welding technique just can guarantee the performance of electric core. The welding technology of the soft-package battery cell tab in the prior art is single, mainly ultrasonic welding is used as a main part, the phenomenon of welding penetration and the like can be caused by overlarge power of ultrasonic welding equipment, and the phenomenon of cold joint and the like can be caused by undersize power.

Content of application

The present application is directed to solving at least one of the problems in the prior art.

Therefore, a first objective of the present application is to provide a battery module, which can ensure that the problem of poor welding of the snack can not occur, and ensure good performance of the battery core;

a second objective of the present application is to provide a battery pack, which includes the above battery module;

a third object of the present application is to provide a vehicle including the battery pack described above.

In order to achieve the above object, a first aspect of the present application provides a battery module including: the battery pack comprises a plurality of battery cores, each battery core group comprises a plurality of battery cores provided with pole pieces, and the pole pieces in each battery core group are superposed to form a pole piece group; and the lug is fixedly connected with the plurality of pole piece groups.

According to the battery module, all pole pieces in the battery module are divided into the plurality of pole piece groups, the pole lugs respectively weld the plurality of pole piece groups, and the condition of insufficient welding is avoided by increasing the welding area at the pole lugs; meanwhile, the overcurrent capacity of the lug can be increased, and the phenomenon that the internal resistance of the alternating current part of the battery cell is too large to influence the performance of the battery module is avoided.

Further, the pole piece is a positive pole piece and the tab is a positive pole tab; or the pole piece is a negative pole piece and the pole ear is a negative pole ear.

Further, a plurality of the electric core groups are stacked, and a plurality of the pole piece groups are arranged in a staggered manner in the transverse direction of the electric core groups.

Further, the tab includes: the tab body and a plurality of connecting parts arranged on the tab body, wherein each connecting part is fixedly connected with the corresponding tab group.

Further, adjacent two of the connecting portions are spaced apart to form an open groove.

Further, the cross-sectional area of each connecting portion is smaller than the cross-sectional area of the tab body.

Further, a plurality of the electric core groups include: the first electric core group and the second electric core group; the first battery core group comprises a plurality of first battery cores, each first battery core is provided with a first pole piece, the first pole pieces are superposed to form a first pole piece group, the second battery core group comprises a plurality of second battery cores, each second battery core is provided with a second pole piece, and the second pole pieces are superposed to form a second pole piece group.

Further, the first pole piece group and the second pole piece group are respectively welded and fixed with the pole lugs.

The second aspect of the present application provides a battery pack, including the battery module.

The third aspect of the application provides a vehicle, which comprises the battery pack.

Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

Drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic view of a tab structure according to an embodiment of the present application;

FIG. 2 is a top view of a first electric core assembly according to an embodiment of the present application;

FIG. 3 is a plan view of a second electric core assembly according to the embodiment of the present application;

fig. 4 is a plan view of the first cell set stacked with the second cell set according to the embodiment of the present application.

Reference numerals:

the first electric core group 1, the first pole piece group 11,

the second electric core group 2, the second pole piece group 21,

a tab 3, a tab body 31, a connecting part 32, a slot 301,

a hot melt adhesive strip 4.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

A battery module according to an embodiment of the present application is described below with reference to fig. 1 to 4, including: a plurality of electric core groups and a tab 3.

Specifically, each electric core group comprises a plurality of electric cores provided with pole pieces, and the pole pieces in each electric core group are superposed to form a pole piece group; the tab 3 is fixedly connected with a plurality of tab groups.

The soft-package battery cell tab welding technology in the prior art is single, and mainly uses ultrasonic welding as a main part. Along with electric automobile to the increase of battery reserves demand, electric core is more and more thick, positive and negative pole piece number of piles constantly increases, and the superpose of pole piece group in the same position becomes more and more thick, makes the welding degree of difficulty of pole piece group and utmost point ear 3 increase, and the concrete expression does: the pole piece can be welded through when the ultrasonic welding equipment is used with overlarge power, and the pole piece can be welded through when the ultrasonic welding equipment is used with the overlarge power.

In this application, divide into a plurality of electric core groups with whole electric core, a plurality of pole pieces superpose in every electric core group forms the utmost point piece group, and the position of the pole piece on every electric core group on electric core is different, is equivalent to several groups of thickness of whole utmost point piece group, and the subdividing is connected with utmost point ear 3 respectively, can solve among the prior art the too thick difficult welded problem of utmost point piece group.

According to the battery module, all pole pieces in the battery module are divided into a plurality of pole piece groups, the pole lugs 3 are used for welding the plurality of pole piece groups respectively, and the false welding condition is avoided by increasing the welding area of the pole lugs 3; meanwhile, the overcurrent capacity of the lug 3 can be increased, and the phenomenon that the internal resistance of the alternating current part of the battery cell is too large to influence the performance of the battery module is avoided.

According to one embodiment of the present application, the pole piece is a positive pole piece and the tab 3 is a positive pole tab; or the pole piece is a negative pole piece and the tab 3 is a negative pole tab. The battery module comprises a plurality of battery core groups, each battery core group comprises a plurality of battery cores, one battery core is provided with a pole piece, and the pole piece can be a positive pole piece or a negative pole piece; the positive pole pieces are superposed to form a positive pole piece group, the positive pole lugs are connected with the positive pole piece group, the negative pole pieces are superposed to form a negative pole piece group, and the negative pole lugs are connected with the negative pole piece group.

According to one embodiment of the application, a plurality of electric core groups are stacked, and a plurality of pole piece groups are staggered in the transverse direction of the electric core groups. As shown in fig. 4, the battery module includes a plurality of electric core groups, each electric core group includes a plurality of electric cores, each electric core has a pole piece, the pole pieces on the same electric core group are cut at the same position, and the pole pieces between different electric core groups are cut at different positions; after a plurality of electric core groups are stacked together, a plurality of electric core groups can be overlapped completely, and a plurality of pole piece groups on the plurality of electric core groups after being overlapped completely are staggered and arranged on the transverse direction of the whole electric core group, so that the pole lugs 3 are connected with the pole piece groups conveniently.

According to an embodiment of the present application, the tab 3 includes: the tab comprises a tab body 31 and a plurality of connecting parts 32 arranged on the tab body 31, wherein each connecting part 32 is fixedly connected with a corresponding pole piece group. Specifically, each connecting portion 32 on the tab body 31 is connected to the corresponding pole piece group on the electric core group.

In one embodiment according to the present application, adjacent two connecting portions 32 are spaced apart to form an open channel 301; each connecting portion 32 has a cross-sectional area smaller than that of the tab body 31. Design like this when utmost point ear 3 department causes the intensification too high through the heavy current, the connecting portion 32 of utmost point ear can be preferentially fused, breaks off the connection between the pole piece, avoids electric core safety problems such as thermal runaway to appear.

It should be noted that still be provided with hot melt adhesive tape 4 on utmost point ear 3, outer plastic-aluminum membrane wraps up the battery module, then heats hot melt adhesive tape 4 and plastic-aluminum membrane, makes hot melt adhesive tape 4 and plastic-aluminum membrane glue together, and hot melt adhesive tape 4 plays the heat-seal effect, and hot melt adhesive tape 4 also is the insulating cement simultaneously, makes plastic-aluminum membrane direct contact utmost point ear 3 not, prevents utmost point ear and plastic-aluminum membrane circular telegram.

According to an embodiment of the present application, the plurality of electric core groups include: a first electric core group 1 and a second electric core group 2; the first cell group 1 includes a plurality of first cells, each first cell is provided with a first pole piece, the plurality of first pole pieces are stacked to form a first pole piece group 11, the second cell group 2 includes a plurality of second cells, each second cell is provided with a second pole piece, and the plurality of second pole pieces are stacked to form a second pole piece group 21.

Specifically, the first pole piece group 11 and the second pole piece group 21 are respectively welded and fixed with the pole ear 3. First pole piece group 11 and second pole piece group 21 can weld on the first face of weld of utmost point ear 3, also can first pole piece group 11 weld on first face of weld or second face of weld, and second pole piece group 2 welds on second face of weld or first face of weld.

It should be noted that first pole piece group 11 and second pole piece group 21 are welded together by positive pole tabs for positive pole piece groups, or welded together by negative pole tabs for negative pole piece groups.

According to one embodiment of the application, an integral battery cell is divided into two battery cell groups, each pole piece on the two battery cell groups is cut respectively, the cutting positions of the pole pieces on the same battery cell group are the same, and a plurality of pole pieces are superposed to form a pole piece group; after the cutting is finished, the two electric core groups are superposed, and at the moment, the two electric core groups can be completely superposed, but the two electrode plate groups are arranged in a staggered manner in the transverse direction of the whole electric core group; and finally, respectively welding the two pole piece groups with the two connecting parts 32 of the pole lugs to obtain the battery cell.

According to an embodiment of the present application, a battery pack includes the battery module. The battery pack has good performance and small internal resistance, and avoids safety problems such as thermal runaway and fire when the current is too large and the temperature is too high.

According to a vehicle in the embodiment of the application, the vehicle comprises the battery pack. The vehicle battery has good performance, the connecting part 32 of the pole lug 3 can be fused preferentially when the battery pack is overheated, and the property and life safety of consumers are not influenced.

In the description of the present application, "the first feature" and "the second feature" may include one or more of the features.

In the description of the present application, "a plurality" means two or more.

In the description herein, reference to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the application, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery module, comprising:

the battery pack comprises a plurality of battery cores, each battery core group comprises a plurality of battery cores provided with pole pieces, and the pole pieces in each battery core group are superposed to form a pole piece group;

the tab (3) is fixedly connected with the plurality of tab groups;

the tab (3) includes: the tab comprises a tab body (31) and a plurality of connecting parts (32) arranged on the tab body (31), wherein each connecting part (32) is fixedly connected with the corresponding tab group;

adjacent two of the connecting portions (32) are spaced apart to form an open channel (301).

2. The battery module according to claim 1, wherein the pole piece is a positive pole piece and the tab (3) is a positive tab; or the pole piece is a negative pole piece and the pole lug (3) is a negative pole lug.

3. The battery module according to claim 1, wherein a plurality of the electrode core groups are stacked, and a plurality of the electrode sheet groups are staggered in a transverse direction of the electrode core groups.

4. The battery module according to claim 1, wherein each of the connecting portions (32) has a cross-sectional area smaller than that of the tab body (31).

5. The battery module according to claim 1, wherein the plurality of the electric core groups comprise: a first electric core group (1) and a second electric core group (2);

the first battery core group (1) comprises a plurality of first battery cores, each first battery core is provided with a first pole piece, the first pole pieces are stacked to form a first pole piece group (11), the second battery core group (2) comprises a plurality of second battery cores, each second battery core is provided with a second pole piece, and the second pole pieces are stacked to form a second pole piece group (21).

6. The battery module as recited in claim 5, wherein the first pole piece group (11) and the second pole piece group (21) are welded and fixed with the pole ear (3), respectively.

7. A battery pack comprising the battery module according to any one of claims 1 to 6.

8. A vehicle characterized by comprising the battery pack according to claim 7.