CN221201342U

CN221201342U - Battery cell shell

Info

Publication number: CN221201342U
Application number: CN202323012992.3U
Authority: CN
Inventors: 刘彬华; 李名英; 朱伯礼; 高云雷; 于子龙; 陈杰; 郑明清
Original assignee: Zhejiang Liwei Energy Technology Co ltd
Current assignee: Zhejiang Liwei Energy Technology Co ltd
Priority date: 2023-11-08
Filing date: 2023-11-08
Publication date: 2024-06-21
Anticipated expiration: 2033-11-08

Abstract

The utility model belongs to the technical field of lithium ion battery preparation, and particularly relates to a battery cell shell, wherein the battery cell shell is divided into a battery cell main body area and an edge sealing area, an accommodating groove is punched in the battery cell shell main body area and is used for accommodating a bare battery cell, in the edge sealing area, the battery cell shell does not need to punch pits, an aluminum plastic film in the edge sealing area cannot be stretched, so that the thickness of the edge sealing area can be reduced, the thickness of the edge sealing area cannot influence the integral safety of the battery cell shell, and the thickness of the edge sealing area is smaller than that of the main body area.

Description

Battery cell shell

Technical Field

The utility model belongs to the technical field of lithium ion battery preparation, and particularly relates to a battery cell shell.

Background

The lithium ion battery has the advantages of high energy density, no memory effect, long cycle life, environmental friendliness and the like, is remarkable in a chemical energy storage device, and is widely paid attention to industries such as electric automobiles, 3C and the like. Generally, lithium batteries are used in series and parallel in groups, and the consistency of the lithium batteries has an important influence on the performance of the series-parallel battery pack.

In the main body area and the non-main body area of the battery cell, the aluminum plastic films have different functions, so that the requirements on the aluminum plastic films are different. In the non-main body area of the cell, only enough melt adhesive effect and the minimum aluminum layer thickness are required to be ensured to prevent external moisture from entering the cell, and simultaneously prevent HF (electrolyte) inside the cell from corroding outwards. At present, the thickness of all parts of the aluminum plastic film which is conventionally used is kept consistent, so that the thickness of the aluminum plastic film in a non-main body area of the battery cell is far beyond the use requirement of the aluminum plastic film, the width of the folded battery cell is increased, and the energy density of the battery cell is reduced.

Disclosure of utility model

The utility model aims at: aiming at the defects of the prior art, the battery cell shell is provided to solve the technical problems that the thickness of a non-main body area of the traditional battery cell shell is too thick, the width of the folded battery cell shell is increased, and the energy density of the battery cell is reduced.

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

the utility model provides a battery cell shell, includes the casing, the casing includes main part district and banding district, the banding district sets up around the main part district, just the thickness of banding district is less than the thickness of main part district.

Further, the main body area is provided with an accommodating groove, and the accommodating groove is used for installing the battery cell.

Further, the depth of the accommodating groove is 0.5-10mm.

Further, the shell is an aluminum plastic film, and the aluminum plastic film is formed by stacking a matte layer, a protective layer, a bonding layer, an aluminum layer and a PP layer.

Further, the aluminum layer thickness and the PP layer thickness of the edge seal region are smaller than the aluminum layer thickness and the PP layer thickness of the body region.

Further, the thickness of the aluminum layer of the edge sealing area is D3, the thickness of the aluminum layer of the main body area is D1, and the aluminum layer of the edge sealing area satisfies the relation: d3 =d1×a (30% +.a < 100%).

Further, the PP layer thickness of the edge sealing area is D4, the PP layer thickness of the main body area is D2, and the PP layer of the edge sealing area satisfies the relationship: d4 =d2×b (30% +.b < 100%).

Further, the main body region further comprises a top sealing part arranged on one side of the accommodating groove, the top sealing part is provided with a cavity for accommodating the tab, and the cavity is communicated with the accommodating groove and the outside of the shell.

Further, the edge sealing area comprises a first side sealing part and a second side sealing part, the first side sealing part and the second side sealing part are respectively arranged at two sides of the main body area, and the area of the second side sealing part is larger than that of the first side sealing part.

Further, the second side seal part is provided with an air bag, and the air bag is communicated with the accommodating groove.

The battery cell shell has the beneficial effects that the battery cell shell is divided into the battery cell main body area and the edge sealing area, the accommodating groove is punched in the battery cell shell main body area and is used for accommodating the bare battery cell, the battery cell shell does not need to be punched in the edge sealing area, the side sealing area cannot be stretched, so that the thickness of the side sealing area can be reduced, the integral safety of the battery cell shell cannot be influenced by the reduction of the thickness of the side sealing area, the thickness of the edge sealing area is smaller than that of the main body area, the aluminum plastic film is stretched when the main body area is punched, the thickness of the aluminum plastic film is reduced by stretching, and if the thickness of the aluminum plastic film is too small, the aluminum plastic film of the edge sealing area is broken when the hole is punched, therefore, the thickness of the folded edge of the battery cell is reduced, and the energy density of the battery cell is improved.

Drawings

Features, advantages, and technical effects of exemplary embodiments of the present utility model will be described below with reference to fig. 1 to 4.

FIG. 1 is a schematic view of the overall structure of a housing according to the present utility model;

FIG. 2 is a schematic view of the bottom of the shell after being covered in the present utility model;

FIG. 3 is a schematic view of the overall thickness of the aluminum plastic film according to the present utility model;

FIG. 4 is a schematic view of the overall thickness of an aluminum plastic film according to the prior art.

In the figure: 1. a housing; 2. an aluminum plastic film;

11. a body region; 12. edge sealing areas;

111. A receiving groove; 112. a top seal;

121. a first side seal; 122. a second side seal;

21. A matte layer; 22. a protective layer; 23. a bonding layer; 24. an aluminum layer; 25. PP layer.

Detailed Description

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description of the application and the claims and the description of the drawings above are intended to cover a non-exclusive inclusion.

In the description of embodiments of the present application, the technical terms "first," "second," and the like are used merely to distinguish between different objects and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, a particular order or a primary or secondary relationship. In the description of the embodiments of the present application, the meaning of "plurality" is two or more unless explicitly defined otherwise.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of the present application, the term "and/or" is merely an association relationship describing an association object, and indicates that three relationships may exist, for example, a and/or B may indicate: a alone, both a and B, and a plurality of cases alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

In the description of the embodiments of the present application, the term "plurality" means two or more (including two), and similarly, "plural sets" means two or more (including two), and "plural sheets" means two or more (including two).

In the description of the embodiments of the present application, the orientation or positional relationship indicated by the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationship shown in the drawings, and are merely for convenience of description and simplification of the description, and do not indicate or imply that the apparatus or element referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of the present application.

In the description of the embodiments of the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured" and the like should be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally formed; or may be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the embodiments of the present application will be understood by those of ordinary skill in the art according to specific circumstances.

The present utility model will be described in further detail with reference to fig. 1 to 4, but the present utility model is not limited thereto.

The battery cell casing comprises a casing 1, wherein the casing 1 comprises a main body area 11 and a sealing edge area 12, the sealing edge area 12 is arranged around the main body area 11, and the thickness of the sealing edge area 12 is smaller than that of the main body area 11. The battery cell casing is divided into a battery cell main body area 11 and an edge sealing area 12, the accommodating groove 111 is punched in the battery cell main body area 11 of the battery cell casing 1, the accommodating groove 111 is used for accommodating a bare battery cell, the battery cell casing in the edge sealing area 12 does not need to be punched with pits, the side sealing area cannot be stretched, the thickness of the side sealing area can be reduced, the thickness of the side sealing area cannot influence the overall safety of the battery cell casing, the thickness of the edge sealing area 12 is smaller than that of the main body area 11 because the aluminum plastic film 2 is punched and stretched when the main body area 11 is punched, the thickness of the aluminum plastic film 2 can be reduced by stretching, if the thickness of the aluminum plastic film 2 is too small, the aluminum plastic film 2 can be punched when punching the pits, so the layer thickness of the edge sealing area 12 is reduced, the folded thickness of the battery cell is reduced, and the energy density of the battery cell is improved.

In some embodiments, the body region 11 is provided with a receiving groove 111, the receiving groove 111 being used for mounting the battery cells. The main effect of electric core shell is with thereby electric core cladding and shell in the protection electric core, and set up the mounting electric core that is used for holding the holding tank 111 of electric core in electric core shell can be better, holding tank 111 can also play fixed spacing's effect to electric core simultaneously, prevents that the electric core from taking place the skew.

In some embodiments, the depth of the receiving groove 111 is 0.5-10mm. The depth of the cavity of the accommodating groove 111 is 0.5mm, 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm and 10mm, wherein the specific depth of the accommodating groove 111 in this embodiment is 5mm, and the accommodating groove 111 with the depth of 5mm can accommodate most small battery cells, so that the accommodating groove has universality. Of course, the depth of the accommodating groove 111 is not fixed in the present embodiment, and the depth of the accommodating groove 111 can be appropriately adjusted according to the thickness of the battery cell.

In some embodiments, the housing 1 comprises an aluminum plastic film 2, the aluminum plastic film 2 being composed of a stack of a matte layer 21, a protective layer 22, an adhesive layer 23, an aluminum layer 24 and a PP layer 25. The matte layer 21 contains a light absorbing substance, and the light absorbing substance can absorb a part of light energy in the incident light and then convert the light energy into heat energy or other forms of energy, the converted heat energy can keep the battery cell at a temperature favorable for improving the energy of the battery cell all the time, and meanwhile, the appearance is improved or an additional chemical corrosion resistance protection function is provided, the protective layer 22 is used for protecting the shell, preventing the shell from being damaged, reducing scratches and dirt infection, ensuring the good appearance of the battery cell, effectively preventing air, especially oxygen, from penetrating so as to maintain the internal environment of the battery cell stable, and also ensuring the good deformability of the packaging aluminum foil; the aluminum layer 24 is used for preventing external water vapor from entering the battery cell, preventing HF inside the battery cell from corroding outwards, providing certain strength, protecting the battery cell in the battery cell shell, preventing potential safety hazards of the battery cell caused by damage to the battery cell, the aluminum layer 24 also has certain electric conduction capacity, improving the output capacity of the battery cell, the PP film has higher melting point and better chemical resistance, electrolyte is injected into the shell after the battery cell is installed, the electrolyte has certain corrosiveness, the PP layer 25 has certain corrosion resistance and cannot be dissolved and swelled by organic solvents in the electrolyte, and the PP layer 25 is used for preventing the aluminum layer 24 from being corroded by the electrolyte; the PP layer 25 also has good thermal stability and can maintain good physical and chemical properties at higher temperatures.

In this embodiment, the stacking sequence of the cell housings from top to bottom is: a matte layer 21, a protective layer 22, an adhesive layer 23, an aluminium layer 24 and a lowermost PP layer 25, wherein the adhesive layer 23 is used to adhere the aluminium layer 24 and the protective layer 22 together.

In some embodiments, the aluminum layer 24 thickness of the border region 12 is less than the aluminum layer 24 thickness of the body region 11, and the PP layer 25 thickness of the border region 12 is less than the PP layer 25 thickness of the body region 11. The thickness of the aluminum layer 24 and the PP layer 25 of the main body area 11 is unchanged, so that the aluminum plastic film 2 is prevented from being broken when a pit is punched, and the aluminum layer 24 and the PP layer 25 of the edge sealing area 12 are not required to be punched or stretched, so that the thickness of the aluminum layer 24 and the PP layer 25 of the edge sealing area 12 is reduced, the structural strength of the battery cell shell is not changed, meanwhile, the thickness of the edge sealing area 12 is reduced, the occupied space of the battery cell shell can be reduced when the edge sealing area 12 is folded, and the energy density is greatly improved.

In some embodiments, the aluminum layer 24 of the edge sealing region 12 has a thickness D3, the aluminum layer 24 of the body region 11 has a thickness D1, and the aluminum layer 24 of the edge sealing region 12 satisfies the relationship: d3 =d1×a (30% +.a < 100%). In this embodiment, a is 30%, 40%, 50%, 60%, 70%, 80%, 90%, specifically 40%, the thickness D1 of the aluminum layer 24 of the main body region 11 is 40 μm, the thickness D3 of the aluminum layer 24 of the edge sealing region 12 is 16 μm according to the above formula, and setting the thickness of the aluminum layer 24 of the edge sealing region 12 to 16 μm can maximally improve the energy density of the battery.

In some embodiments, the PP layer 25 of the edge seal area 12 has a thickness D4, the PP layer 25 of the body area 11 has a thickness D2, and the PP layer 25 of the edge seal area 12 satisfies the relationship: d4 =d2×b (30% +.b < 100%). In this embodiment, b is 30%, 40%, 50%, 60%, 70%, 80%, 90%, specifically 40%, the thickness D2 of the PP layer 25 of the body region 11 is 45 μm, and it can be obtained according to the above formula that the thickness D4 of the PP layer 25 of the edge sealing region 12 is 18 μm, and setting the thickness of the edge sealing region 12 to 18 μm can maximally increase the energy density of the battery.

In some embodiments, the body region 11 includes a receiving groove in which the receiving groove 111 is provided, and a top seal 112 provided with a cavity for receiving the tab, the cavity communicating the receiving groove with the outside of the case 1. After placing the electric core in the holding tank, fold in half plastic-aluminum membrane 2, encapsulate top seal portion 112 afterwards, encapsulate top seal portion 112 at first and can prevent that the electric core from coming off in holding tank 111, make things convenient for subsequent process, and the tab is placed in the cavity, and the one end and the electric core pole piece of tab carry out fixed connection, and the other end stretches out the cavity and is connected with the consumer.

In some embodiments, the edge sealing region 12 includes a first side sealing portion 121 and a second side sealing portion 122, the first side sealing portion 121 and the second side sealing portion 122 are disposed on two sides of the main body region, and the area of the second side sealing portion 122 is larger than the area of the first side sealing portion 121. After the battery cell is placed in the accommodating groove 111, the aluminum plastic film 2 is folded in half, and then the first side seal 121 and the second side seal 122 are sealed, but an opening is left when the second side seal 122 is sealed, the opening is used for injecting electrolyte, the electrolyte is injected into the battery case through the opening, and then the opening is sealed.

In some embodiments, the second side seal 122 is provided with an air pocket that communicates with the receiving groove 111. After the battery cell and the battery cell shell are assembled, the battery can be subjected to a first formation step, waste gas can be generated during formation, and the gas bag is used for containing the waste gas formed after formation.

Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the embodiments of the disclosure may be suitably combined to form other embodiments as will be understood by those skilled in the art.

Variations and modifications of the above embodiments will occur to those skilled in the art to which the utility model pertains from the foregoing disclosure and teachings. Therefore, the present utility model is not limited to the above-described embodiments, but is intended to be capable of modification, substitution or variation in light thereof, which will be apparent to those skilled in the art in light of the present teachings. In addition, although specific terms are used in the present specification, these terms are for convenience of description only and do not limit the present utility model in any way.

Claims

1. The utility model provides a electricity core shell which characterized in that: the shell comprises a main body area and an edge sealing area, wherein the edge sealing area is arranged around the main body area, and the thickness of the edge sealing area is smaller than that of the main body area.

2. The cell housing of claim 1, wherein: the main body area is provided with an accommodating groove, and the accommodating groove is used for installing the battery cell.

3. The cell housing of claim 2, wherein: the depth of the accommodating groove is 0.5-10mm.

4. A cell housing according to claim 3, wherein: the shell is an aluminum plastic film, and the aluminum plastic film is formed by stacking a matte layer, a protective layer, a bonding layer, an aluminum layer and a PP layer.

5. The cell housing of claim 4, wherein: the aluminum layer thickness and the PP layer thickness of the edge sealing area are smaller than the aluminum layer thickness and the PP layer thickness of the main body area.

6. The cell housing of claim 5, wherein: the aluminum layer thickness of the edge sealing area is D3, the aluminum layer thickness of the main body area is D1, and the aluminum layer of the edge sealing area meets the relation: d3 =d1×a (30% +.a < 100%).

7. The cell housing of claim 6, wherein: the PP layer thickness of the edge sealing area is D4, the PP layer thickness of the main body area is D2, and the PP layer of the edge sealing area meets the relation: d4 =d2×b (30% +.b < 100%).

8. The cell housing of claim 7, wherein: the main body area further comprises a top sealing part arranged on one side of the accommodating groove, a cavity for accommodating the lug is formed in the top sealing part, and the accommodating groove is communicated with the outside of the shell through the cavity.

9. The cell housing of claim 8, wherein: the edge sealing area comprises a first side sealing part and a second side sealing part, the first side sealing part and the second side sealing part are respectively arranged on two sides of the main body area, and the area of the second side sealing part is larger than that of the first side sealing part.

10. The cell housing of claim 9, wherein: the second side seal part is provided with an air bag, and the air bag is communicated with the accommodating groove.