CN212517391U

CN212517391U - Buffer structure and battery module

Info

Publication number: CN212517391U
Application number: CN202021564166.3U
Authority: CN
Inventors: 程克强; 杜肖源; 谷亮杰
Original assignee: China Aviation Lithium Battery Co Ltd; China Aviation Lithium Battery Research Institute Co Ltd
Current assignee: Avic Innovation Technology Research Institute Jiangsu Co ltd; China Aviation Lithium Battery Co Ltd; China Lithium Battery Technology Co Ltd; CALB Technology Co Ltd
Priority date: 2020-07-31
Filing date: 2020-07-31
Publication date: 2021-02-09
Anticipated expiration: 2030-07-31

Abstract

The utility model relates to the technical field of batteries, a buffer structure and battery module are disclosed, this buffer structure includes buffer unit and spacing unit, and wherein, buffer unit includes two contact surfaces that set up relatively and connects global of two contact surfaces, and spacing unit encloses the global of locating buffer unit, cooperates with buffer unit to it is spacing to buffer unit. The battery module comprises at least two batteries and a buffer structure positioned between the two batteries. The buffer structure and the battery module improve the problem that the bottom end of the buffer cushion is easy to deform and is extruded out of the large surfaces of the adjacent battery monomers.

Description

Buffer structure and battery module

Technical Field

The disclosure relates to the technical field of batteries, in particular to a buffer structure and a battery module.

Background

In the battery module, generally, a cushion pad is arranged between adjacent battery monomers, so that the purpose of providing initial pretightening force for the battery monomers is achieved.

The casing of the battery cell is usually cuboid, the bottom end of the large surface is a round angle, when the cushion pad is clamped by the large surfaces of the adjacent battery cells, a gap is reserved between the round angle part of the large surface and the cushion pad, so that the cushion pad cannot be clamped, and the clamping force on the bottom end of the cushion pad is small. Meanwhile, in the process of the battery monomer cyclic bulging, due to internal gas generation and other reasons, the shell can expand, the closer to the edge of the shell, the larger the constraint effect of the shell is, the farther away from the edge, the smaller the constraint effect of the shell is, and the larger the bulging in the middle area of the shell is, so that the trend of extruding the cushion pad outwards can be generated. Due to the two factors and the gravity action of the buffer cushion, the bottom end of the buffer cushion is easy to deform and expand outwards to be extruded between the large surfaces of the adjacent battery cells, and the part of the buffer cushion extruded between the large surfaces of the adjacent battery cells loses the buffer effect.

SUMMERY OF THE UTILITY MODEL

The utility model provides a buffer structure and battery module for improve the bottom of blotter and be out of shape easily and be extruded the problem between the adjacent battery monomer broadside.

In order to achieve the above purpose, the present disclosure provides the following technical solutions:

a cushioning structure, comprising: the buffer unit comprises two contact surfaces which are oppositely arranged and a peripheral surface which is connected with the two contact surfaces;

and the limiting unit is arranged around the peripheral surface of the buffer unit and matched with the buffer unit so as to limit the buffer unit.

The utility model provides a buffer structure encloses in the global outside of buffer unit and is equipped with spacing unit, and spacing unit can play the restriction effect to buffer unit, reduces buffer unit deformation, the possibility of outside expansion, avoids buffer unit deformation, outside expansion even to can reduce buffer unit's bottom and be extruded the possibility between the adjacent battery monomer big face, can make the better performance cushioning effect of buffer structure.

The present disclosure further provides a battery module, which includes at least two battery cells and any one of the buffer structures provided in the above technical solutions between the two battery cells.

This battery module that openly provides includes two at least battery monomers and is located two battery monomers between arbitrary buffer structure as provided in above-mentioned technical scheme, therefore can reach the beneficial effect that above-mentioned buffer structure can reach at least: the possibility that the bottom end of the buffer unit is extruded out of the large faces of the adjacent battery monomers is reduced, and the buffer structure can better play a buffer role.

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 be arranged differently as is known in the art. Further, in the drawings, like reference characters designate the same or similar parts throughout the several views.

Fig. 1 is a schematic structural diagram of a buffer unit in a buffer structure provided in an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of a limiting unit in a buffer structure provided in the embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of a battery module according to an embodiment of the present disclosure;

fig. 4 is a schematic diagram of a buffer structure provided in an embodiment of the disclosure;

FIG. 5 is an exploded view of the cushioning structure shown in FIG. 4;

fig. 6 is a schematic structural diagram of another buffer unit in the buffer structure provided in the embodiment of the present disclosure;

FIG. 7 is an exploded view of a cushioning layer of the cushioning unit shown in FIG. 6;

fig. 8 is a schematic structural diagram of another buffer unit in the buffer structure provided in the embodiment of the present disclosure.

Icon: 1-a buffer unit; 101-a contact surface; 102-a peripheral surface; 11-a buffer layer; 12-a thermally insulating layer; 111-a buffer; 112-a heat absorber; 113-a buffer; 114-insulation; 115 — a first encapsulation layer; 116-a second encapsulation layer; 117-supporting feet; 2-a limiting unit; 21-a limiting membrane; 22-first coating film; 23-a second coating film; 3-third coating film; 4-a fourth cover film; 100-a buffer structure; 200-battery cell.

Detailed Description

The technical solutions in the exemplary embodiments of the present disclosure will be clearly and completely described below with reference to the 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, unless otherwise explicitly specified or limited, the terms "first", "second", and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; the term "plurality" means two or more; the term "and/or" includes any and all combinations of one or more of the associated listed items. In particular, reference to "the" object or "an" object is also intended to mean one of many such objects possible.

The terms "connected," "secured," and the like are to be construed broadly and unless otherwise stated or indicated, and for example, "connected" may be a fixed connection, a removable connection, an integral connection, an electrical connection, or a signal connection; "connected" may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present disclosure can be understood by those skilled in the art as the case may be.

Further, in the description of the present disclosure, it is to be understood that the directional words "upper", "lower", "inner", "outer", etc., which are described in the exemplary embodiments of the present disclosure, are described at the angles shown in the drawings, and should not be construed as limiting the exemplary embodiments of the present disclosure. It will also be understood that, in this context, when an element or feature is referred to as being "on", "under", or "inner", "outer" with respect to another element(s), it can be directly on "," under ", or" inner "," outer "with respect to the other element(s), or indirectly on", "under", or "inner", "outer" with respect to the other element(s) via intervening elements.

The buffering structure 100 provided by the present embodiment includes a buffering unit 1 as shown in fig. 1 and a limiting unit 2 as shown in fig. 2, wherein the buffering unit 1 includes two contact surfaces 101 disposed opposite to each other and a circumferential surface 102 connecting the two contact surfaces 101, and the limiting unit 2 is disposed around the outer side of the circumferential surface 102 of the buffering unit 1 and is matched with the buffering unit 1 to limit the buffering unit 1.

Above-mentioned buffer structure 100 encloses in the global 102 outside of buffer unit 1 and is equipped with spacing unit 2, and spacing unit 2 can play the restriction effect to buffer unit 1, reduces buffer unit 1 and warp, the possibility of outside expansion, avoids buffer unit 1 to warp even, outside expansion to can reduce the bottom of buffer unit 1 and be extruded the possibility between the adjacent battery monomer 200 big face, can make the better cushioning effect of performance of buffer structure 100.

The contact surface 101, i.e., the surface of the cushion unit 1 facing the large surface of the battery cell 200, is the largest surface of the battery cell 200, i.e., the surface having the largest area among the battery cells 200.

Specifically, when the buffer unit 1 is arranged, the buffer unit 1 may be a complete sheet, or may be a frame-shaped structure, that is, the coverage area of the buffer structure 100 may be the entire large surface of the battery cell 200, or may be only the area near four edges of the battery cell 200 (as shown in fig. 3); the buffer unit 1 is an elastic body with compression resilience, and the material thereof can be silicone rubber, foamed silica gel, foamed polypropylene (i.e. foamed PP) and the like.

When the limiting unit 2 is specifically arranged, the material of the limiting unit 2 may be a non-metal material with excellent tensile strength and low elongation, for example: PET (Polyethylene terephthalate) or a flexible material.

In order to simplify the structure of the limiting unit 2 and save the cost, in one implementation, the limiting unit 2 includes a limiting film 21, and the limiting film 21 is enclosed outside the peripheral surface 102 of the buffer unit 1 and attached to the peripheral surface 102.

At this time, in order to facilitate the positioning of the buffering structure 100, in one implementation, at least two supporting legs 117 may be disposed at intervals at the bottom of the buffering structure 100. In order to avoid the need to distinguish the upper and lower ends during assembly, at least two support legs 117 may be disposed at intervals at both the upper and lower ends of the cushioning structure 100. In another implementation, at least two ribs are integrally formed at the bottom end of the limiting unit 2 and are positioned by the ribs.

Further, with continued reference to fig. 2, in order to strengthen the constraint effect on the buffer unit 1, the buffer structure 100 includes a first coating film 22 and a second coating film 23, the first coating film 22 is connected to one side of the limiting film 21 and at least coats the edge of the corresponding contact surface 101; the second coating film 23 is connected to the other side of the stopper film 21, and coats at least the edge of the corresponding contact surface 101.

In one implementation, the first coating film 22, the limiting film 21, and the second coating film 23 may be integrally formed.

Specifically, when the limiting unit 2 is provided, in one implementation, as shown in fig. 4 and 5, the buffer structure 100 may further include a third coating film 3 that covers the surface of one contact surface 101 and extends to the outside of the contact surface 101, and a fourth coating film 4 that covers the surface of the other contact surface 101 and extends to the outside of the contact surface 101, and a portion of the third coating film 3 that extends to the outside of the corresponding contact surface 101 is attached to a portion of the fourth coating film 4 that extends to the outside of the corresponding contact surface 101 to form the limiting unit 2.

When the cushion unit 1 has a frame-shaped structure, the third coating film 3 and the fourth coating film 4 may or may not be connected to each other on the inner hole side of the frame-shaped structure.

The first coating film 22, the second coating film 23, the third coating film 3, and the fourth coating film 4 are all insulating coating films.

In an alternative technical solution, as shown in fig. 6, the buffer unit 1 includes a buffer layer 11 and a heat insulation layer 12 coated on both sides of the buffer layer 11.

The thermal insulation layers 12 are arranged on the two sides of the buffer layer 11, and when the buffer structure 100 is located in the battery module and a certain battery cell 200 is in thermal runaway, the thermal insulation layers 12 can block heat transfer and reduce the possibility of thermal diffusion.

Specifically, when the heat insulating layer 12 is provided, the heat insulating layer 12 may include a mica sheet or a mica cloth; the insulating layer 12 may be bonded to the cushion layer 11.

The mica cloth and the mica sheet have smaller heat conductivity coefficient and better heat insulation performance.

When better heat insulation or fire prevention is required, the heat insulation layer 12 may be made of heat insulation and fire prevention material.

Further, as shown in fig. 7, the buffer layer 11 includes a buffer body 111 and a heat absorbing body 112.

The thermal insulating layer 12 is provided on both sides of the buffer layer 11, and the buffer layer 11 includes the buffer body 111 and the heat absorbing body 112, and the thermal insulating layer 12 and the heat absorbing body 112 have a dual function, thereby further reducing the possibility of thermal diffusion when thermal runaway occurs in a certain battery cell 200.

When the heat absorber 112 is specifically arranged, the heat absorber 112 may include a heat-absorbing phase change layer, for example: heat absorbing phase change paper.

The heat-absorbing phase change paper has small heat conductivity coefficient and good heat absorption and heat insulation performance; the heat is taken away through the gasification of the phase-change material, so that the service life and the safety performance of the battery can be improved.

Specifically, when the buffer body 111 is provided, the buffer body 111 may be in a frame shape, for example: the heat absorber 112 is located in the area surrounded by the buffer 111 and connected to the buffer 111.

Of course, the buffer body 111 may also be a complete piece, and in this case, the heat absorbing body 112 may be one attached to one side of the buffer body 111; two buffer bodies 111 may be provided, one on each side.

The buffer structure 100 provided by the scheme is applied to the battery module as follows: the buffer structure 100 is uniformly arranged between every two adjacent battery cells 200 (or between every string of batteries of a multi-parallel module) according to design requirements when the battery module is assembled;

when thermal runaway occurs in a battery cell 200 during charging and discharging of the battery module, heat transfer is blocked by the heat insulating layer 12 and the heat absorbing body 112; if the thermal runaway generates large heat, the heat absorbing body 112 starts to absorb the heat and gasify and decompose, taking away the heat. Therefore, the buffer structure 100 can achieve good heat insulation and heat absorption effects, and can effectively inhibit heat transfer to the adjacent battery cells 200, thereby ensuring the thermal stability and safety performance of the battery module and reducing the occurrence of safety accidents.

In another implementation, as shown in fig. 8, the buffer layer 11 includes a heat insulation portion 114, a frame-shaped buffer portion 113, a first packaging layer 115, and a second packaging layer 116, wherein the heat insulation portion 114 is located in an area surrounded by the buffer portion 113 and connected to the buffer portion 113; one of the first sealing layer 115 and the second sealing layer 116 is sealed to one side of the buffer portion 113 and the heat insulating portion 114, and the other is sealed to the other side of the buffer portion 113 and the heat insulating portion 114.

When the buffering part 113 is specifically arranged, the buffering part 113 can be made of silicon rubber which is compressible, so that a good buffering effect can be achieved.

Specifically, when the heat insulation portion 114 is provided, the heat insulation portion 114 may include aerogel felt, and the aerogel felt has a small thermal conductivity and a good heat insulation performance.

Specifically, when the first sealing layer 115 and the second sealing layer 116 are provided, both of them may be insulating films such as a PET film or a PI (polyimide film) film, and are sealed outside the heat insulating portion 114 and the buffer portion 113 by a hot press method.

Further, the thickness of the heat insulating portion 114 is smaller than that of the cushioning portion 113, and there is a gap between both side surfaces of the heat insulating portion 114 and the corresponding surfaces of the cushioning portion 113.

In order to reduce cost, etc., the first packaging layer 115 and the second packaging layer 116 may not be provided during the manufacturing process, and the thermal insulation layer 12 is directly bonded and packaged.

The application of this scheme in battery module is as follows: when the battery module is assembled, the buffer structures 100 are uniformly arranged between every two adjacent battery monomers 200 (or between every string of batteries of a multi-parallel module) according to design requirements, and if the supporting legs 18 exist, the supporting legs 117 are used for positioning during assembly to ensure the installation position;

when the battery cell 200 deforms during the charging and discharging processes of the battery module, the buffer part 113 is compressed to absorb the bulging force of the battery cell 200, the gap between the buffer part 113 and the heat insulation part 114 is reduced, and the bulging space of the battery cell 200 can be effectively ensured; meanwhile, after the buffer part 113 is compressed, two heat insulation layers 12, a heat insulation part 114 and two gap air layers which are 5 layers are arranged for heat insulation, so that a good heat insulation effect can be achieved, heat transfer to the adjacent single battery 200 can be effectively inhibited, the thermal stability and the safety performance of the battery module are guaranteed, and safety accidents are reduced.

When the battery cell 200 bulges and deforms greatly, after the gap air layer between the heat insulation part 114 and the corresponding packaging layer is completely occupied, the heat insulation part 114 can be compressed to buffer the bulging force, meanwhile, the compressed heat insulation part 114 also has a good heat insulation effect, three layers of heat insulation are still provided, the heat transfer between the adjacent battery cells 200 is blocked, and therefore the service life and the use safety of the battery module are improved.

In the embodiment, each layer can be directly cut by a coiled material or a sheet material and then connected by hot pressing or bonding, so that the batch automatic production is convenient to realize.

As shown in fig. 3, the battery module provided by this embodiment includes at least two battery cells and any one of the buffer structures provided in the above technical solutions between two battery cells, the buffer structure is provided with a limiting unit around the outer side of the peripheral surface of the buffer unit, the limiting unit can play a role in constraining the buffer unit, reduce the possibility of deformation and outward expansion of the buffer unit, even avoid the deformation and outward expansion of the buffer unit, thereby reducing the possibility that the bottom end of the buffer unit is squeezed out of the large surfaces of the adjacent battery cells, and enabling the buffer structure to better exert a buffering effect.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the invention 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. It is intended that the specification and example embodiments be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

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

Claims

1. A cushioning structure, comprising: the buffer unit comprises two contact surfaces which are oppositely arranged and a peripheral surface which is connected with the two contact surfaces;

2. The cushion structure according to claim 1, wherein the stopper unit includes a stopper film provided on a circumferential surface of the cushion unit.

3. The cushioning structure of claim 2, comprising a first coating film and a second coating film, wherein the first coating film is connected to one side of the limiting film and coats at least the edge of the corresponding contact surface; the second wrapping film is connected to the other side of the limiting film and at least wraps the edge of the corresponding contact surface.

4. The cushioning structure of claim 1, comprising:

the third coating film is coated on the surface of one contact surface and extends to the outer side of the contact surface;

the fourth coating film is coated on the surface of the other contact surface and extends to the outer side of the contact surface;

the part of the third coating film extending to the corresponding outer side of the contact surface is attached to the part of the fourth coating film extending to the corresponding outer side of the contact surface to form the limiting unit.

5. The cushioning structure of claim 1, 2 or 4, wherein the cushioning unit comprises a cushioning layer and a thermal insulating layer coated on both sides of the cushioning layer.

6. The buffer structure of claim 5, wherein the buffer layer comprises a buffer body and a heat absorber, the heat absorber comprising a heat absorbing phase change paper;

and/or the thermal insulation layer comprises a mica sheet.

7. The buffer structure of claim 5, wherein the buffer layer comprises:

a frame-shaped buffer portion;

the heat insulation part is positioned in an area formed by enclosing the buffer part and is connected with the buffer part;

and the first packaging layer and the second packaging layer are packaged on one sides of the buffer part and the heat insulation part, and the other side of the buffer part and the heat insulation part.

8. The cushioning structure according to claim 7, wherein a thickness of the heat insulating portion is smaller than a thickness of the cushioning portion, and a gap is provided between both side surfaces of the heat insulating portion and the corresponding surfaces of the cushioning portion.

9. The cushioning structure of claim 7, wherein the thermal insulation comprises aerogel blanket;

and/or the thermal insulation layer comprises a mica sheet.

10. A battery module, comprising at least two battery cells and the buffer structure of any one of claims 1 to 9 located between the two battery cells.