CN218919053U

CN218919053U - Battery cell and power equipment

Info

Publication number: CN218919053U
Application number: CN202223599772.0U
Authority: CN
Inventors: 辛雪倩
Original assignee: Svolt Energy Technology Co Ltd
Current assignee: Svolt Energy Technology Co Ltd
Priority date: 2022-12-29
Filing date: 2022-12-29
Publication date: 2023-04-25
Anticipated expiration: 2032-12-29

Abstract

The utility model provides a battery cell and power equipment, wherein the battery cell comprises a shell with at least one end arranged in an open mode, a pole group body accommodated in the shell, and a cover plate for blocking the open mode, wherein an explosion-proof device is arranged on the cover plate, an insulating heat conducting layer is filled between the pole group body and the shell, and an exhaust channel penetrating through the pole group body in the length direction is arranged on the insulating heat conducting layer. According to the battery cell, the insulating heat conducting layer is filled between the periphery of the electrode group body and the shell, so that the heat radiating effect of the electrode group body is improved, the temperature of the electrode group body is reduced, the probability of thermal runaway of the battery cell is reduced, and the safety performance of the battery cell is improved; and through the exhaust passage on the insulating heat conduction layer, the gas in the battery cell is discharged through the explosion-proof device, so that the safety of the battery cell is improved.

Description

Battery cell and power equipment

Technical Field

The utility model relates to the technical field of power batteries, in particular to an electric core. Meanwhile, the utility model also relates to power equipment with the battery cell.

Background

Lithium ion batteries have become representative of modern high-performance batteries because of their high operating voltage, high specific energy, large capacity, small self-discharge, good cycling performance, long service life, light weight, small volume, and the like. The high energy density and the high safety performance are the most important indexes of the lithium ion battery and are also key to restrict the development of lithium ions.

The most widely used electrolyte system in lithium ion batteries is a mixed carbonate solution of LiPF6, which is highly volatile, has a low flash point, and burns very easily. When internal short circuit is caused by impact or deformation, a large amount of heat is generated by high-rate charge and discharge and overcharge, resulting in an increase in the temperature of the battery. When a certain temperature is reached, a series of chemical reactions are initiated, so that the heat balance of the battery is destroyed, if the heat cannot be timely evacuated, the reaction is accelerated, a series of self-heating side reactions are initiated, the temperature of the battery is rapidly increased, thermal runaway occurs, the battery is finally burnt, and even explosion occurs in severe cases. In the prior art, the problem of the temperature rise of the battery is generally solved by adopting methods of adding a flame retardant additive, overcharging the additive, using a fluorine-containing solvent, arranging an explosion-proof valve and the like.

In addition, the basic structure of the lithium ion monomer battery cell at present is as follows: the battery cell comprises a shell, a pole group (electrode assembly), a bare battery cell insulating sheet, a cover plate (usually provided with a pole column and a liquid injection hole), an explosion-proof mechanism and the like, wherein the shell and the cover plate form a closed space for accommodating the electrode assembly, a large number of gaps exist between the pole group and the shell, and heat dissipation of the battery cell is affected.

Disclosure of Invention

In view of the above, the present utility model is directed to a battery cell to improve the heat dissipation and the air exhaust effects of the battery cell, thereby improving the safety of the battery cell.

In order to achieve the above purpose, the technical scheme of the utility model is realized as follows:

the battery cell comprises a shell with at least one end arranged in an open way, a pole group body accommodated in the shell, and a cover plate for blocking the open way, wherein an explosion-proof device is arranged on the cover plate;

an insulating heat conducting layer is filled between the pole group body and the shell, and an exhaust channel which is communicated with the pole group body along the length direction is arranged on the insulating heat conducting layer.

Further, the exhaust passage is a plurality of arranged at intervals along the circumferential direction of the pole group body.

Further, the areas of the plurality of exhaust channels positioned on the same side are 60-70% of the corresponding side area of the pole group body.

Further, a plurality of through holes penetrating through the insulating heat conducting layer in the thickness direction are formed in the insulating heat conducting layer, and the through holes are communicated with the exhaust channel.

Further, the through holes are arranged on the insulating heat conducting layer at intervals along the length direction of the pole group body.

Further, the exhaust channel is a groove arranged on one side of the insulating heat conducting layer, which faces the shell;

the height of the groove is 1/3-1/2 of the thickness of the insulating heat conducting layer.

Further, the insulating heat conducting layer is in interference fit with the pole group body and the shell;

and/or the thickness range of the insulating heat conducting layer is 0.4-0.5 mm.

Further, the insulating heat conducting layer is fixedly connected to the pole group body and/or the shell in a hot melting mode.

Further, the insulating heat-conducting layer is made of heat-conducting silica gel or heat-conducting silicone grease.

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

according to the battery cell, the insulating heat conducting layer is filled between the electrode group body and the shell, so that the heat radiating effect of the electrode group body is improved, the temperature of the electrode group body is reduced, the probability of thermal runaway of the battery cell is reduced, and the safety performance of the battery cell is improved; and through the exhaust passage on the insulating heat conduction layer, the gas in the battery cell is discharged through the explosion-proof device, so that the safety of the battery cell is improved.

In addition, the exhaust efficiency inside the battery cell is improved through a plurality of exhaust channels. The arrangement of the occupied area of the exhaust channel is beneficial to improving the exhaust efficiency and is convenient for arrangement and implementation. The arrangement of the through holes is beneficial to further improving the exhaust efficiency. Through the through hole along the length direction interval arrangement of utmost point group body, do benefit to the arrangement implementation, and exhaust effect is good. The groove has a simple structure and is convenient for processing and forming.

In addition, the insulating heat conduction layer is in interference fit, so that the heat conduction efficiency between the pole group body and the shell is improved. The insulating heat conduction layer is fixedly connected in a hot melting mode, so that arrangement and implementation are facilitated, and the connecting effect is good. The heat-conducting silica gel or heat-conducting silicone grease is mature in product and has good insulating heat-conducting property.

In addition, another object of the present utility model is to propose a power plant in which the battery cell as described above is provided.

The power equipment provided by the utility model is beneficial to improving the cooling performance and the safety performance of the power equipment by arranging the battery cell, and has better practicability.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description serve to explain the utility model. In the drawings:

fig. 1 is a schematic structural diagram of an insulating and heat conducting layer according to an embodiment of the present utility model;

reference numerals illustrate:

1. an insulating heat conducting layer; 101. an exhaust passage; 102. and a through hole.

Detailed Description

It should be noted that, without conflict, the embodiments of the present utility model and features of the embodiments may be combined with each other.

In the description of the present utility model, it should be noted that, if terms indicating an azimuth or a positional relationship such as "upper", "lower", "inner", "back", and the like are presented, they are based on the azimuth or the positional relationship shown in the drawings, only for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or element to be referred to must have a specific azimuth, be constructed and operated in a specific azimuth, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, if any, are also used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The utility model will be described in detail below with reference to the drawings in connection with embodiments.

The embodiment relates to an integral battery cell, which comprises a shell with at least one end arranged in an open manner, a pole group body contained in the shell, and a cover plate for blocking the open, wherein an explosion-proof device is arranged on the cover plate. An insulating heat conducting layer 1 is filled between the pole group body and the shell, and an exhaust channel 101 which is arranged in a penetrating manner along the length direction of the pole group body is arranged on the insulating heat conducting layer 1.

Based on the above general description, an exemplary structure of the insulating and heat conducting layer 1 in the present embodiment is shown in fig. 1. The battery cell in this embodiment is a blade battery cell in the prior art, both ends of the housing are provided with cover plates, and an explosion-proof device is arranged on one cover plate, and of course, the battery cell in this embodiment may also be a square battery cell in the prior art, and at this time, one end of the housing is provided with the cover plate and the explosion-proof device. The explosion-proof device in this embodiment may adopt a mature product in the prior art, for example, the explosion-proof device adopts an explosion-proof valve, and the product is mature, which is beneficial to improving the safety of the battery cell. In this embodiment, the gas exhausted from the exhaust channel 101 is specifically exhausted outside the battery cell through the explosion-proof valve.

The whole cuboid that is of utmost point group body in this embodiment, insulating heat conduction layer 1 parcel is outside the utmost point group body, and specifically, insulating heat conduction layer 1 winds around establishing in the circumference of utmost point group body, and insulating heat conduction layer 1's both ends overlap joint sets up to have better parcel effect. In particular, the insulating and heat-conducting layer 1 is preferably fastened to the pole group body and/or the housing by means of hot-melt. In addition, the insulating heat conduction layer 1 is in interference fit with the pole group body and the shell, so that the heat conduction effect between the pole group body and the shell is improved, heat generated by the pole group body is transferred to the shell, the heat dissipation effect of the pole group body is improved, and the safety of the battery cell in use is improved.

The thickness of the insulating and heat conducting layer 1 in this embodiment ranges from 0.4 to 0.5mm, for example, 0.4mm, 0.45mm or 0.5mm. In specific implementation, the thickness of the insulating and heat conducting layer 1 can be selected according to the distance between the pole group body and the shell.

In order to improve the exhaust efficiency, the exhaust channels 101 in this embodiment are a plurality of exhaust channels 101 arranged at intervals along the circumferential direction of the pole group body, and the areas of the exhaust channels 101 on the same side are 60-70% of the corresponding side areas of the pole group body. In specific implementation, the exhaust channel 101 is a groove arranged on one side of the insulating and heat conducting layer 1 facing the shell, and the height of the groove is 1/3-1/2 of the thickness of the insulating and heat conducting layer 1. For example, the height of the grooves is 1/3 or 1/2 of the thickness of the insulating and heat conducting layer 1. By the arrangement, the exhaust channel 101 is convenient to process, shape and arrange on the insulating heat conducting layer 1, and the exhaust efficiency of the insulating heat conducting layer 1 in use is improved.

In order to further improve the exhaust efficiency of the insulating and heat conducting layer 1 in use, in this embodiment, as shown in fig. 1, a plurality of through holes 102 are provided on the insulating and heat conducting layer 1, which are disposed through the thickness direction thereof, and the through holes 102 are in communication with the exhaust passage 101. As a preferred embodiment, a plurality of through holes 102 are provided on the insulating and heat conducting layer 1 at intervals along the length direction of the pole set body.

The insulating heat conduction layer 1 in the embodiment is made of heat conduction silica gel or heat conduction silicone grease, and the insulating heat conduction layer and the heat conduction silicone grease have good insulating and heat conduction effects, so that the safety and the heat dissipation effect of the battery cell are improved.

When the battery cell is assembled, the negative electrode lug and the negative electrode pole on the pole group body are welded, the insulating heat conducting layer 1 is wrapped on the outer side of the pole group body, then the positive electrode cover plate is installed, the insulating heat conducting layer 1 is respectively bonded and fixed with the positive electrode cover plate and the negative electrode cover plate in a plastic cement manner, and finally the pole group body is put into the shell.

In addition, the insulating and heat conducting layer 1 of the embodiment can be formed by knotting a fluid material, the electrode group body welded with the cathode electrode post is firstly assembled into the shell, the fluid insulating and heat conducting material is filled into the gap between the shell and the electrode group body under pressure before the cathode electrode tab and the electrode post are welded, and then the insulating and heat conducting material is solidified and molded, well filled between the shell and the electrode group body, so that good contact between the electrode group body and the shell is realized, and the heat conducting efficiency is greatly improved.

According to the battery cell, the insulating heat conducting layer 1 is filled between the electrode group body and the shell, so that the heat radiating effect of the electrode group body is improved, the temperature of the electrode group body is reduced, the probability of thermal runaway of the battery cell is reduced, and the safety performance of the battery cell is improved; and through the exhaust channel 101 on the insulating heat conducting layer 1, the gas inside the battery cell is discharged through the explosion-proof device, so that the safety of the battery cell is improved. In addition, the insulating heat conducting layer 1 can also play a good insulating effect, reduce the occurrence of short circuit problem between the pole group body and the shell, and further facilitate improving the safety performance of the battery cell. In addition, the insulating heat conducting layer 1 in this embodiment can improve the laminating effect of utmost point group body and casing greatly, makes the utmost point group body in time guide in the casing through the heat conduction because of the heat that electrochemical reaction produced, later through thermal diffusion, goes out heat diffusion, greatly reduced explosion-proof valve opening rate, the security of the electric core of effective assurance.

In addition, the embodiment also relates to a power equipment, wherein the battery cell is arranged in the power equipment. The power equipment of this embodiment can be battery module or battery package etc. through setting up electric core as described above, do benefit to improvement power equipment's cooling performance and security performance, and have better practicality.

The foregoing description of the preferred embodiments of the utility model is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the utility model.

Claims

1. The utility model provides an electric core which characterized in that: the battery cell comprises a shell with at least one end arranged in an open way, a pole group body accommodated in the shell, and a cover plate for blocking the open way, wherein an explosion-proof device is arranged on the cover plate;

2. The cell of claim 1, wherein:

the exhaust passage is a plurality of arranged at intervals along the circumferential direction of the pole group body.

3. A cell according to claim 2, characterized in that:

the areas of the exhaust channels on the same side are 60-70% of the corresponding side areas of the pole group body.

4. The cell of claim 1, wherein:

the insulating heat conduction layer is provided with a plurality of through holes which are communicated with the exhaust channel.

5. The cell of claim 4, wherein:

the through holes are arranged on the insulating heat conducting layer at intervals along the length direction of the pole group body.

6. The cell of claim 1, wherein:

the exhaust channel is a groove arranged on one side of the insulating heat conducting layer, which faces the shell;

7. The cell of claim 1, wherein:

the insulating heat conducting layer is in interference fit with the pole group body and the shell;

8. The cell of claim 1, wherein:

the insulating heat conducting layer is fixedly connected to the pole group body and/or the shell in a hot melting mode.

9. The cell of any one of claims 1 to 8, wherein:

the insulating heat conduction layer is made of heat conduction silica gel or heat conduction silicone grease.

10. A power plant, characterized by: the power equipment is provided with the battery cell as claimed in any one of claims 1 to 9.