CN212783704U

CN212783704U - Multi-tab structure of cylindrical battery

Info

Publication number: CN212783704U
Application number: CN202021471574.4U
Authority: CN
Inventors: 侯要; 路高磊; 徐柏兴; 左威威
Original assignee: Zhengzhou Bak New Energy Automobile Co ltd
Current assignee: Zhengzhou Bak New Energy Automobile Co ltd
Priority date: 2020-07-23
Filing date: 2020-07-23
Publication date: 2021-03-23
Anticipated expiration: 2030-07-23

Abstract

The utility model belongs to the technical field of lithium battery structures, in particular to a cylindrical battery multi-tab structure, which comprises a pole piece and tabs, wherein the tabs comprise a plurality of tabs I and a tab II; the plurality of the first tabs and the second tabs are arranged on one side of the pole piece, the distance between the plurality of the first tabs and the second tabs is gradually increased, and the plurality of the first tabs and the second tabs are annularly arranged after the pole piece is wound into a winding core; the first tab comprises a vertical surface and an inclined surface, and the inclined surface and the vertical surface form a certain included angle. The utility model discloses not only can reduce the battery internal resistance, can realize moreover that utmost point ear overlap joint is double-deck material, avoided utmost point ear too thick and the rosin joint that produces, welding reliability is high, has improved battery manufacturing process.

Description

Multi-tab structure of cylindrical battery

Technical Field

The utility model belongs to the technical field of the lithium cell structure, concretely relates to many utmost point ear structures of cylinder type battery.

Background

In recent years, with the consumption of fossil fuels and the development of society, energy and environmental issues have attracted increasing attention. Compared with the traditional lead-acid battery, the lithium ion battery has the advantages of high energy density, long cycle life, low self-discharge, wide working temperature and the like, and is widely applied to the fields of electric tools, electric automobiles, energy storage and the like. When the lithium ion battery is applied, a plurality of lithium ion batteries are connected in series and in parallel to form a group to achieve required voltage and electric quantity, the traditional single-lug battery has large polarization during discharge at multiplying power, high internal resistance, high temperature rise during discharge, easy thermal runaway and incapability of meeting the discharge requirement of large multiplying power, so that the multi-lug battery is more and more widely applied.

In the production process of the multi-tab battery, after the positive pole piece, the diaphragm and the negative pole piece are wound to form a roll core, a plurality of positive pole tabs on the positive pole piece are required to be welded together firstly to form a total positive pole tab, then the total positive pole tab is welded together with the cap, a plurality of negative pole tabs on the negative pole piece are welded together to form a total negative pole tab, then the total negative pole tab is welded together with the steel shell, and the multi-tab roll core is connected with the cap and the steel shell. However, because the number of the tabs is large, and the tabs are overlapped, the thickness of the total positive electrode tab or the total negative electrode tab is large, and the cold joint is easily generated during the welding with the cap or the steel shell, so that the poor conduction of the lithium battery is caused.

Disclosure of Invention

In order to overcome the defect that exists among the prior art, the utility model provides a many utmost point ear structures of cylinder type battery not only can reduce the battery internal resistance, can realize moreover that utmost point ear overlap joint is double-deck material, has avoided utmost point ear too thick and the rosin joint that produces, and welding reliability is high, has improved battery manufacturing process.

In order to achieve the above object, the utility model adopts the following technical scheme:

the utility model discloses a cylindrical battery multi-tab structure, which comprises a pole piece and tabs, wherein each tab comprises a plurality of tabs I and a tab II; the plurality of the first tabs and the second tabs are arranged on one side of the pole piece, the distance between the plurality of the first tabs and the second tabs is gradually increased, and the plurality of the first tabs and the second tabs are annularly arranged after the pole piece is wound into a winding core; the first tab comprises a vertical surface and an inclined surface, and the inclined surface and the vertical surface form a certain included angle.

Further, the pole piece is a positive pole piece or a negative pole piece.

Further, the vertical surface and the inclined surface of the first electrode lug are of an integrally formed structure or a split welding structure.

Furthermore, the longitudinal section of the vertical surface of the first electrode lug is rectangular, and the longitudinal section of the inclined surface of the first electrode lug is trapezoidal.

Further, the number of the first tabs is at least three.

Furthermore, the lower part of the longitudinal section of the second electrode lug is rectangular, and the upper part of the longitudinal section of the second electrode lug is arc-shaped.

Furthermore, the inclined planes of the first bent lugs and the second bent lugs are in a lap joint state in sequence.

Furthermore, the lap joint of the tabs is made of double-layer materials.

Compared with the prior art, the utility model has the advantages of it is following:

the utility model discloses a cylindrical battery multi-tab structure, through setting up a plurality of utmost point ear one and utmost point ear two into the interval and increase gradually, can realize that pole piece twines a plurality of utmost point ear one and utmost point ear two and is the annular arrangement after rolling up the core, utmost point ear one includes vertical face and becomes the inclined plane of certain contained angle with vertical face, bends utmost point ear one, utmost point ear two, and the utmost point ear is overlap joint state in proper order after bending, and this state can realize the electricity between the utmost point ear and connect, can realize again that utmost point ear overlap joint department is double-deck material, has avoided the utmost point ear too thick and the rosin joint that produces, and the welding reliability is high, has; and the internal resistance of the cylindrical battery is reduced, and the overcurrent capacity of the battery is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

Fig. 1 is a schematic diagram of a pole piece expansion according to an embodiment of the present invention;

fig. 2 is an effect diagram of the pole lug after the pole piece is wound according to the embodiment of the present invention;

fig. 3 is the effect diagram of the pole piece after winding and the pole ear after bending and welding.

The reference numbers in the figures denote:

1. the pole piece comprises a pole piece, 2, a first pole lug, 3, a vertical surface, 4, an inclined surface and 5, a second pole lug.

Detailed Description

In order to make the technical solutions in the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, but not all embodiments.

As shown in fig. 1, the cylindrical battery multi-tab structure of the embodiment includes a pole piece 1 and tabs, where the pole piece 1 may be a positive pole piece or a negative pole piece, the tabs include four tabs one 2 and one tab two 5, the four tabs one 2 and the one tab two 5 are disposed on one side of the pole piece 1, and the four tabs one 2 and the tab two 5 are arranged at intervals that gradually increase, as shown in fig. 2, the four tabs one 2 and the tab two 5 are annularly arranged after the pole piece 1 is wound into a roll core, so as to facilitate bending and overlapping of subsequent tabs; the first tab 2 comprises two parts, namely a vertical surface 3 and an inclined surface 4, the inclined surface 4 and the vertical surface 3 form a certain included angle, as shown in fig. 3, the first tab 2 can be bent along the root part of the vertical surface 3 by using the existing manufacturing process, the second tab 5 is bent, the inclined surfaces 4 of the first tab 2 are in a sequentially overlapped state after being bent, and the first tab 2 which is sequentially overlapped is welded on the second tab 5 which is bent, so that the state can realize the electric connection between the tabs, and can also realize that the overlapped parts of the tabs are both double-layer materials, thereby avoiding the insufficient welding caused by the excessive thickness of the tabs, having high welding reliability and improving the battery manufacturing process; the multi-lug cylindrical battery has low internal resistance, improves the overcurrent capacity of the battery and avoids thermal runaway.

Preferably, the vertical surface 3 and the inclined surface 4 of the tab one 2 are of an integrally formed structure or a separately welded structure. The size of the included angle between the vertical surface 3 and the inclined surface 4 of the first electrode lug 2 can be adjusted according to the actual battery model (18650 model, 21700 model or other). The number of the tabs one 2 is not limited to four in the present embodiment, and may be any one of more than three. The utility model discloses the overlap joint of mentioning all adopts welding process.

As shown in fig. 1 and 2, in the present embodiment, the vertical section of the vertical surface 3 of the first tab 2 is rectangular, the longitudinal section of the inclined surface 4 is trapezoidal, the lower portion of the longitudinal section of the second tab 5 is rectangular, and the upper portion is arc-shaped, although the shapes of the first tab 2 and the second tab 5 are not limited to the above shape.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The use of the terms "a" or "an" and the like in the description and in the claims of this application do not necessarily denote a limitation of quantity. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

Finally, it is to be noted that: the above description is only the preferred embodiment of the present invention, which is only used to illustrate the technical solution of the present invention, and is not used to limit the protection scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention is included in the protection scope of the present invention.

Claims

1. A multi-tab structure of a cylindrical battery comprises a pole piece and tabs and is characterized in that the tabs comprise a plurality of tabs I and a tab II; the plurality of the first tabs and the second tabs are arranged on one side of the pole piece, the distance between the plurality of the first tabs and the second tabs is gradually increased, and the plurality of the first tabs and the second tabs are annularly arranged after the pole piece is wound into a winding core; the first tab comprises a vertical surface and an inclined surface, and the inclined surface and the vertical surface form a certain included angle.

2. The cylindrical battery multi-tab structure as claimed in claim 1, wherein the electrode sheet is a positive electrode sheet or a negative electrode sheet.

3. The multi-tab structure of the cylindrical battery as claimed in claim 1, wherein the vertical surface and the inclined surface of the first tab are integrally formed or separately welded.

4. The cylindrical battery multi-tab structure as claimed in claim 3, wherein the vertical section of the vertical surface of the tab I is rectangular, and the vertical section of the inclined surface is trapezoidal.

5. The cylindrical battery multi-tab structure as claimed in claim 1, wherein the number of the tab one is at least three.

6. The cylindrical battery multi-tab structure as claimed in claim 1, wherein the lower portion of the longitudinal section of the tab II is rectangular, and the upper portion is arc-shaped.

7. The multi-tab structure of a cylindrical battery as claimed in claim 1, wherein the inclined planes of the tabs after bending and the tabs after bending are in a sequentially overlapping state.

8. The cylindrical battery multi-tab structure as claimed in claim 7, wherein the tab lap joint is a double-layer material.