CN212725431U

CN212725431U - Soft-packaged cylindrical battery cell

Info

Publication number: CN212725431U
Application number: CN202021406275.2U
Authority: CN
Inventors: 周玲; 曹礼; 李雄成
Original assignee: Hunan Lifang New Energy Science and Technology Co Ltd
Current assignee: Hunan Lifang New Energy Science and Technology Co Ltd
Priority date: 2020-07-16
Filing date: 2020-07-16
Publication date: 2021-03-16
Anticipated expiration: 2030-07-16

Abstract

The utility model provides a soft-packaged cylindrical battery cell, which comprises a battery cell main body and a shell, wherein the battery cell main body is packaged in the shell, and the two ends of the battery cell main body are respectively and electrically connected with a first tab and a second tab; one end of the first tab is exposed out of the shell, and the other end of the first tab is connected with the shell in a sealing manner; one end of the second tab is exposed out of the shell, and the other end of the second tab is not connected with the shell in a sealing manner; an air bag edge area is reserved on at least one side of the shell, a first sealing strip is sealed on one side, close to the second tab, of the air bag edge area, and the distance between the first sealing strip and the battery cell main body is 1-10 mm. Compared with the prior art, the soft-package cylindrical battery core has the advantages that the electrolyte can be quickly infiltrated into the battery core main body, the infiltration effect of the pole piece is accelerated, the standing time is shortened, and the production efficiency is improved.

Description

Soft-packaged cylindrical battery cell

Technical Field

The utility model relates to a lithium cell field, concretely relates to soft-packaged cylinder electricity core.

Background

After present cylinder electricity core coiling is accomplished, usually package together with the plastic-aluminum membrane with both ends positive and negative pole ear earlier, reserve air pocket limit breach and be used for annotating the liquid, then arrange electric core in the oven and toast, the breach of reserving by the air pocket limit after toasting is annotated liquid, electrolyte infiltration principle is mainly through the diaphragm and the pole piece at electric core upper and lower both ends gradually to middle diffusion in order to accomplish and soaks, can refer to the schematic structure of figure 1, and also annotate liquid by the air pocket limit in the industry at present basically, electrolyte flows into electric core main part along the not district's passageway of both ends utmost point ear encapsulation position, again permeate into electric core main part in by the both ends of electric core gradually, but adopt this kind of liquid mode of annotating to have following several problems:

1) the design of the channels of the unsealed areas in the electric core is small; the method is mainly influenced by the design limitation of the battery cell, because if the unsealed area is increased, the battery cell is easy to be overlong and ugly in appearance, but the difficulty of electrolyte entering the battery cell is increased due to the smaller unsealed area, so that the electrolyte infiltration effect is poor, the standing time is usually required to be prolonged to increase the absorption of the electrolyte, and the production efficiency is greatly influenced;

2) the gas bag can not ensure that the battery cell can fully absorb the electrolyte when injecting the liquid, and serious quality accidents such as poor electrical property of the battery cell, lithium precipitation of a pole piece and the like caused by insufficient infiltration of the electrolyte often exist.

In view of the above, it is necessary to provide a technical solution to the above problems.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a: the utility model provides a soft-packaged cylindrical battery cell, the electrolyte infiltration of this electric core is effectual, shortens the time of stewing when guaranteeing that electrolyte is fully absorbed, promotes production efficiency.

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

a soft-packaged cylindrical battery cell comprises a battery cell main body and a shell, wherein the battery cell main body is packaged in the shell, and two ends of the battery cell main body are respectively and electrically connected with a first lug and a second lug; one end of the first tab is exposed out of the shell, and the other end of the first tab is connected with the shell in a sealing manner; one end of the second tab is exposed out of the shell, and the other end of the second tab is not connected with the shell in a sealing manner; an air bag edge area is reserved on at least one side of the shell, a first sealing strip is sealed on one side, close to the second tab, of the air bag edge area, and the distance between the first sealing strip and the battery cell main body is 1-10 mm.

The utility model discloses a cylinder electricity core, its second utmost point ear do not with casing sealing connection, reserve out a tip of casing and do not seal the region for electrolyte can directly pour into electric core main part into from this end, and the setting of first seal strip not only can avoid electric core at the removal skew of turnover in-process, has guaranteed simultaneously to have sufficient notes liquid space, makes electrolyte flow in electric core main part fast. Compare in traditional air pocket limit and annotate liquid, the open area of this end is big, and in electrolyte can soak electric core main part internal fast for the infiltration effect of pole piece, not only can shorten the time of stewing and promoted production efficiency, and guaranteed that electric core main part can fully absorb electrolyte, avoided because of the pole piece soaks badly and reduce electric core performance, promoted the quality and the goodness rate of product.

Preferably, the distance between the first seal strip and the battery cell main body is 3-8 mm.

Preferably, the height of the first seal strip is 3.5-12 mm. More preferably, the height of the first seal strip is 5-10 mm. Wherein, the height direction and the direction of the pole lug are the same.

Preferably, the height of the first seal strip is greater than the length of the first seal strip. The first seal strip is arranged to be vertical, so that the seal strip can be conveniently welded and formed.

Preferably, a second seal strip is sealed on one side of the air pocket edge area, which is far away from the battery cell main body.

Preferably, one end of the second seal strip extends to one end of the air bag edge region on the same side as the first tab.

Preferably, the other end of the second seal strip extends to one end of the air bag edge region on the same side as the second tab.

Preferably, the first tab is a negative tab, and the second tab is a positive tab.

Preferably, the negative electrode lug is electrically connected to the bottom end of the battery cell main body, and the positive electrode lug is electrically connected to the top end of the battery cell main body.

Compared with the prior art, the beneficial effects of the utility model reside in that: the utility model provides a soft-packaged cylindrical battery, its second utmost point ear do not with casing sealing connection, reserve out a tip of casing and do not seal the region for electrolyte can directly pour into electric core main part into from this end into, and the setting of first seal strip not only can avoid electric core at the removal skew of turnover in-process, has guaranteed simultaneously that there is sufficient notes liquid space, makes electrolyte can flow in electric core main part fast. Compare in traditional air pocket limit and annotate liquid, the open area of this end is big, and in electrolyte can soak electric core main part internal fast for the infiltration effect of pole piece, not only can shorten the time of stewing and promoted production efficiency, and guaranteed that electric core main part can fully absorb electrolyte, avoided because of the pole piece soaks badly and reduce electric core performance, promoted the quality and the goodness rate of product.

Drawings

Fig. 1 is a schematic structural diagram of a conventional pouch cylindrical battery.

Fig. 2 is the utility model discloses soft packet of cylindrical battery's structural schematic.

In the figure: 1-a cell body; 11-a first tab; 12-a second tab; 13-sealing the joint; 2-a shell; 3-air pocket edge area; 31-a first seal strip; 32-second seal strip.

The area a in fig. 1-2 is an unsealed area channel at a tab packaging position, wherein electrolyte in the existing soft-package cylindrical battery flows into the battery cell main body through the channel; the direction of the arrow near the second tab in fig. 2 is the electrolyte injection position.

Detailed Description

In order to make the technical solutions and advantages of the present invention clearer, the present invention and its advantageous effects will be described in further detail below with reference to the accompanying drawings of the detailed description and the specification, but the present invention is not limited thereto.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "fixed" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The utility model discloses the standard part that uses all can purchase from the market, and dysmorphism piece all can be customized according to the description with the record of drawing of description, and the concrete connection mode of each part all adopts conventional means such as ripe bolt, rivet, welding among the prior art, and machinery, part and equipment all adopt prior art, and conventional model, including circuit connection adopts conventional connection mode among the prior art, does not detailed here again.

As shown in fig. 1-2, a soft-packaged cylindrical battery cell includes a battery cell main body 1 and a casing 2, wherein the battery cell main body 1 is packaged in the casing 2, and a first tab 11 and a second tab 12 are electrically connected to two ends of the battery cell main body 1 respectively; one end of the first tab 11 is exposed out of the shell 2, and the other end of the first tab 11 is connected with the shell 2 in a sealing way; one end of the second tab 12 is exposed outside the shell 2, and the other end of the second tab 12 is not hermetically connected with the shell 2; an air bag edge area 3 is reserved on at least one side of the shell 2, a first seal strip 31 is sealed on one side, close to the second tab 12, of the air bag edge area 3, and the distance between the first seal strip 31 and the cell main body 1 is 1-10 mm.

The air bag edge area 3 is arranged at the position of a conventional air bag edge, namely, at the position perpendicular to the direction of the lug.

Further, the distance between the first seal strip 31 and the cell main body 1 is 3-8 mm. The first sealing strip 31 is welded at a position 3-8 mm away from the electric core main body, so that the situation that an opening for liquid injection is too large and difficult to control due to the fact that the second lug 12 is not packaged is avoided, the situation that the liquid injection is difficult due to the fact that the first sealing strip 31 is too close to the second lug 12 is avoided, and the situation that electrolyte flows down from the second lug 12 quickly and soaks the electric core main body 1 more quickly can be well met at the position; and because the soft package casing 2 is soft generally, and the second pole ear 12 is not connected with the casing 2 in a sealing manner (the sealing connection part 13 can be seen in a part a in fig. 1-2), if the opening is too large, the deviation of the battery cell is easily caused, the seal strip can also avoid the movement deviation of the battery cell in the process of procedure turnover, so that a positioning effect is achieved, and the limitation of the numerical value not only ensures that the battery cell has enough liquid injection space, but also can avoid the displacement of the battery cell. The seal strip can be fixed in a sealing mode by welding or heat sealing. The distance is a vertical distance between two nearest edges of the cell main body 1 and the first seal strip 31. The length of the first seal strip 31 can be determined by referring to the height thereof, and the specific value is not limited herein.

Further, the height of the first seal strip 31 is 3.5-12 mm. Preferably, the height of the first seal strip 31 is 5 to 10 mm. Wherein, the height direction and the direction of the tab are the same direction, as shown in the b direction in fig. 2.

Further, the height of the first seal strip 31 is greater than the length of the first seal strip 31. The first seal strip 31 is arranged in a vertical shape, so that the seal strip can be conveniently welded and formed. The length direction of the first seal stripe 31 is shown as the direction c in fig. 2.

Further, a second seal strip 32 is sealed on the side of the gas pocket edge region 3 away from the cell main body 1. One end of the second seal strip 32 extends to one end of the air bag edge region 3 on the same side as the first tab 11; the other end of the second seal strip 32 extends to one end of the air pocket side region 3 on the same side as the second pole ear 12. The second seal strip 32 extends to a position where one end of the first tab 11 contacts with the sealed joint 13 of the first tab 11, where the sealed joint 13 is a sealed joint where the first tab 11 is connected with the casing 2, and even after the first tab 11 is hermetically connected with the casing 2, a part of unsealed area still exists between the first tab 11 and the cell main body 1, as shown in a in fig. 2, extending the second seal strip 32 to contact with the sealed joint 13 can also ensure that the unsealed area is in a sealed state, thereby avoiding a situation that the electrolyte may flow out after the electrolyte is subsequently injected. The other end of the second seal strip 32 extends to the end of the air bag side region 3 on the same side as the second tab 12, which not only ensures the stability of the whole air bag side region 3, but also further enhances the stability of the liquid injection port.

Further, the first tab 11 is a negative tab, and the second tab 12 is a positive tab. Namely, the liquid is injected from the positive tab, the negative tab and the shell 2 are connected in a sealing way, and after the liquid injection is finished, the positive tab and the shell 2 are connected in a sealing way. And compared with the negative electrode tab, the material of the positive electrode tab is more corrosion-resistant, so that the performance of the electrolyte is protected, and the stability of the battery is also ensured.

Further, the negative electrode lug is electrically connected to the bottom end of the battery cell main body 1, and the positive electrode lug is electrically connected to the top end of the battery cell main body 1. The electrolyte gradually infiltrates the middle part and the low end of the battery core from the top under the action of gravity, the infiltration effect is good, and the battery core can be quickly absorbed.

The preparation method of the soft-packaged cylindrical battery cell comprises the following steps:

s1, winding and preparing a winding core according to the sequence of the anode, the diaphragm and the cathode, wherein the anode is electrically connected with an anode tab, the cathode is electrically connected with a cathode tab, the shell 2 is punched, the prepared winding core is placed into the shell 2, the shell 2 can be an aluminum-plastic film shell 2, and an air bag edge area 3 is reserved in the shell 2;

s2, sealing the negative tab to the case 2 while maintaining the positive tab in a state of not being sealed to the case 2, and providing a first seal strip 31 in the air pocket edge region 3, the first seal strip 31 being disposed on a side close to the positive tab; the distance between the first seal strip 31 and the battery cell main body 1 is 1-10 mm, the height of the first seal strip 31 is 3.5-12 mm, and the height of the first seal strip 31 is larger than the length of the first seal strip; meanwhile, a second seal strip 32 is sealed on one side of the air bag edge area 3, which is far away from the electric core main body 1, one end of the second seal strip 32 extends to one end of the air bag edge area 3 on the same side with the first tab 11, and the other end extends to one end of the air bag edge area 3 on the same side with the second tab 12;

s3, placing the battery cell in the S2 in an oven for baking, injecting electrolyte from a notch at the top of the battery cell main body 1 in a vacuum state after baking is finished, namely injecting electrolyte from the unsealed position of the positive lug and the shell 2, and based on the arrangement of the position of the seal strip, the electrolyte can be quickly infiltrated into the battery cell from the top of the battery cell, so that the infiltration effect of the battery cell is accelerated;

s4, after the liquid injection is finished, the positive lug is hermetically connected with the shell 2, and the subsequent one-time formation and degassing packaging are carried out; due to the arrangement of the previous cell structure, the cell can absorb electrolyte quickly, the subsequent standing time can be shortened, the production efficiency is improved, the problem of poor performance of the cell caused by poor infiltration of the pole piece is avoided, and the product quality is improved.

Variations and modifications to the above-described embodiments may become apparent to those skilled in the art from the disclosure and teachings of the above description. Therefore, the present invention is not limited to the above-mentioned embodiments, and any obvious modifications, replacements or variations made by those skilled in the art on the basis of the present invention belong to the protection scope of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. The soft-packaged cylindrical battery cell is characterized by comprising a battery cell main body (1) and a shell (2), wherein the battery cell main body (1) is packaged in the shell (2), and two ends of the battery cell main body (1) are respectively and electrically connected with a first tab (11) and a second tab (12); one end of the first tab (11) is exposed out of the shell (2), and the other end of the first tab (11) is connected with the shell (2) in a sealing manner; one end of the second tab (12) is exposed out of the shell (2), and the other end of the second tab (12) is not connected with the shell (2) in a sealing way; an air bag edge area (3) is reserved on at least one side of the shell (2), a first sealing strip (31) is sealed on one side, close to the second tab (12), of the air bag edge area (3), and the distance between the first sealing strip (31) and the battery cell main body (1) is 1-10 mm.

2. The flexible-packaging cylindrical battery cell according to claim 1, wherein the distance between the first seal strip (31) and the battery cell main body (1) is 3-8 mm.

3. The soft-packaged cylindrical battery cell according to claim 1, wherein the height of the first seal strip (31) is 3.5-12 mm.

4. The cylindrical cell according to claim 3, characterized in that the height of the first seal strip (31) is greater than the length of the first seal strip (31).

5. The cylindrical, soft-packed cell as claimed in claim 1, characterized in that a second sealing strip (32) is sealed to the side of the gas pocket edge region (3) remote from the cell body (1).

6. The cylindrical, soft-packed cell as claimed in claim 5, characterized in that one end of the second sealing strip (32) extends to the end of the gas pocket area (3) on the same side as the first tab (11).

7. The cylindrical, soft-packed cell as claimed in claim 6, characterized in that the other end of the second sealing strip (32) extends to the end of the gas pocket area (3) on the same side as the second tab (12).

8. The soft-packaged cylindrical battery cell according to claim 1, wherein the first tab (11) is a negative tab, and the second tab (12) is a positive tab.

9. The flexible-packaging cylindrical battery cell according to claim 8, wherein the negative electrode tab is electrically connected to the bottom end of the battery cell main body (1), and the positive electrode tab is electrically connected to the top end of the battery cell main body (1).