Pouch-type battery cell and secondary battery

Abstract

The utility model belongs to battery technical field, concretely relates to a kind of soft package electric core and secondary battery, wherein;The soft package electric core, including bare electric core, cladding body and side folding body;The installation cavity is equipped in the cladding body;The bare electric core is set in the inside of the installation cavity;The outer side surface of the cladding body away from the installation cavity is equipped with installation groove;One side end of the side folding body is connected to the outer side surface of the cladding body;The other side end of the side folding body is bent towards the installation groove and is arranged;And the other side end of the side folding body is connected to the inside of the installation groove.The utility model can reduce the thickness of the side folding body after bending, to reduce the width of the soft package electric core as a whole;Then volume energy density can be improved and redundant space occupation is reduced;And the safety and stability of use are ensured.

Description

Technical Field

[0001] This utility model belongs to the field of battery technology, and in particular relates to a soft-pack battery cell and a secondary battery. Background Technology

[0002] With the development of the lithium-ion battery market, the requirements for cell energy density are becoming increasingly stringent, as energy density represents a product's market competitiveness. Currently, the mainstream lithium-ion batteries on the market are mainly square aluminum-cased lithium-ion batteries, cylindrical lithium-ion batteries, and pouch lithium-ion batteries. Among them, pouch lithium-ion batteries have the highest energy density due to their use of a thin aluminum-plastic film wrapping.

[0003] However, most existing pouch cells have outward-protruding folded edges, which increases the overall width of the cell and makes it difficult to meet the requirements of high volumetric energy density. In addition, the uniform thickness of the folded edges of pouch cells leads to the accumulation of material at the edge of the electrode, increasing the weight and making it impossible to effectively utilize the internal space. Therefore, it affects the stability and safety of its use and its energy density (ED). Utility Model Content

[0004] The purpose of this utility model is to provide a soft-pack battery cell that addresses the shortcomings of existing technologies by solving the technical problem that excessive overall thickness reduces volumetric energy density.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A pouch battery cell includes a bare battery cell, a casing, and a side-folding body; the casing has a mounting cavity; the bare battery cell is disposed inside the mounting cavity; the outer surface of the casing away from the mounting cavity has a mounting groove; one end of the side-folding body is connected to the outer surface of the casing; the other end of the side-folding body is bent toward the mounting groove; and the other end of the side-folding body is connected to the interior of the mounting groove.

[0007] Preferably, the cover includes a first covering surface, a second covering surface, and at least one side cover; the side cover is disposed between the first covering surface and the second covering surface; and the mounting cavity is formed between the first covering surface, the second covering surface, and the side cover; and one end of the side fold is connected to the first covering surface and / or the side cover; the mounting groove is disposed on the outer surface of the side cover away from the mounting cavity.

[0008] Preferably, the side sealing cover comprises a first vertical sealing section, a first horizontal sealing section and a second vertical sealing section connected in sequence; the first vertical sealing section is connected to the first wrapping surface; one side end of the first horizontal sealing section extends toward the mounting cavity and is connected to one side end of the second vertical sealing section; the second vertical sealing section is connected to the second wrapping surface; and the mounting groove is formed between the surface of the first horizontal sealing section facing away from the mounting cavity and the surface of the second vertical sealing section facing away from the mounting cavity.

[0009] Preferably, the side folded body comprises a first vertical folded section, a first horizontal folded section and a second vertical folded section connected in sequence; the first horizontal folded section is bent and arranged on the first vertical folded section toward the direction of the mounting groove; the surface of the second vertical folded section facing the mounting groove is connected to the second vertical sealing section; and one side end of the second vertical folded section is bent and arranged in the mounting groove toward the direction of the first wrapping surface;

[0010] Wherein, the relationship between the height h2 of the second vertical sealing section and the height X of the second vertical folded section satisfies: 0.8mm≤X≤1.1mm; and X<h2.

[0011] Preferably, the side folded body comprises a third vertical folded section, an inclined folded section and a fourth vertical folded section connected in sequence; the inclined folded section is obliquely connected to the third vertical folded section toward the direction of the mounting groove; the surface of the fourth vertical folded section facing the mounting groove is connected to the second vertical sealing section; and one side end of the fourth vertical folded section extends toward the horizontal plane where the second wrapping surface is located.

[0012] Preferably, the side folded body comprises a fifth vertical folded section and a second horizontal folded section connected in sequence; the second horizontal folded section is bent and arranged on the fifth vertical folded section toward the direction of the mounting groove; and the second horizontal folded section is connected to the first horizontal folded section.

[0013] Preferably, the side sealing cover further comprises a third vertical sealing section and a second horizontal sealing section connected to each other; the third vertical sealing section and the second horizontal sealing section are arranged perpendicular to each other; and a fitting groove is provided between the third vertical sealing section and the second horizontal sealing section; the fitting groove and the mounting groove are respectively arranged opposite to each other on two sides in the width direction of the wrapping body; and the side folded body comprises a sixth vertical folded section and a third horizontal folded section connected to each other; the sixth vertical folded section and the third horizontal folded section are arranged perpendicular to each other and are disposed on the inner wall of the fitting groove.

[0014] Preferably: the side cover includes an inclined encapsulation section; the two ends of the inclined encapsulation section are respectively connected to the first covering surface and the second covering surface; the mounting groove is disposed between the inclined encapsulation section and the side folding body; and the angle between the inclined encapsulation section and its horizontal plane is α, wherein α satisfies: 5°≤α<90°;

[0015] The side-folding body includes a first inclined bending section; one end of the first inclined bending section is connected to the covering body; the other end of the first inclined bending section extends toward the mounting groove.

[0016] Furthermore, the side-folding body also includes a third inclined bending segment and a second inclined bending segment connected in sequence; the third inclined bending segment is bent and disposed in the direction of the mounting groove from the first inclined bending segment; one side surface of the second inclined bending segment facing the mounting groove is connected to the third inclined bending segment; and one side end of the second vertical bending segment is bent and disposed in the mounting groove in the direction of the thickness of the first covering surface.

[0017] This utility model also discloses a battery cell, including a bare battery cell and the aforementioned pouch battery cell; the bare battery cell is disposed inside the mounting cavity.

[0018] This utility model also discloses a battery, including the aforementioned battery cell.

[0019] The beneficial effects of this utility model are that, by adding an installation groove to facilitate the bending and embedding of the side folding body, the thickness of the protruding side folding body after bending is effectively reduced, thereby reducing the overall width of the soft-pack battery cell and optimizing the material distribution in the area where the side folding body is located; thus, the volumetric energy density can be increased, and redundant space occupancy can be reduced; and edge material accumulation can be avoided, ensuring the safety and stability of use; and it can better adapt to the corresponding assembly space of the terminal, improving space utilization. Attached Figure Description

[0020] The following will refer to the appendix. Figures 1-9 This section describes the features, advantages, and technical effects of exemplary embodiments of the present invention.

[0021] Figure 1 This is a schematic diagram of the structure of a soft-pack battery cell according to an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the soft-pack battery cell according to the first embodiment of this utility model;

[0023] Figure 3 This is a schematic diagram of the structure of the soft-pack battery cell according to the second embodiment of this utility model;

[0024] Figure 4This is a schematic diagram of the structure of the soft-pack battery cell according to the third embodiment of this utility model;

[0025] Figure 5 This is a schematic diagram of the structure of the soft-pack battery cell according to the fourth embodiment of this utility model;

[0026] Figure 6 This is a schematic diagram of the structure of the soft-pack battery cell according to the fifth embodiment of this utility model;

[0027] Figure 7 This is a schematic diagram of the structure of the soft-pack battery cell according to the sixth embodiment of this utility model;

[0028] Figure 8 This is a schematic diagram of the structure of the soft-pack battery cell according to the seventh embodiment of this utility model;

[0029] Figure 9 This is a schematic diagram of the structure of a battery cell according to an embodiment of the present invention.

[0030] In the diagram: 1-Encapsulation body; 101-Mounting groove; 102-Mounting cavity; 103-First sub-cavity; 104-Second sub-cavity; 105-Assembly groove; 11-First encapsulation surface; 12-Second encapsulation surface; 13-Side cover; 131-First vertical encapsulation section; 132-First horizontal encapsulation section; 133-Second vertical encapsulation section; 134-Inclined encapsulation section; 135-Second horizontal encapsulation section; 136-Third vertical encapsulation section; 2-Bare cell; 21-Separator; 22-First electrode; 23-Second electrode; 3-Side fold body; 31-Outer fold segment; 32-Inner fold segment; 301-First vertical bend segment; 302-First horizontal bend segment; 303-Second vertical bend segment; 304-Third vertical bend segment; 305-Fourth inclined bend segment; 306-Fourth vertical bend segment; 307-Fifth vertical bend segment; 308-Second horizontal bend segment; 3091-Third horizontal bend segment; 3092-Sixth vertical bend segment; 3093-First inclined bend segment; 3094-Second inclined bend segment; 3095-Third inclined bend segment; 4-Adhesive component. Detailed Implementation

[0031] Unless otherwise defined, 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 pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0032] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0033] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0034] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or multiple situations existing alone. In addition, the character " / " in this document generally indicates that the related objects before and after are in an "or" relationship.

[0035] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0036] The following is in conjunction with the appendix Figures 1-9 The present invention will be described in further detail, but this is not intended to limit the scope of the present invention.

[0037] like Figure 1 As shown, in one embodiment of this utility model, the soft-pack battery cell includes a bare battery cell 2, a casing 1, and a side-folding body 3; the casing 1 has an installation cavity 102; the bare battery cell 2 is disposed inside the installation cavity 102; the outer surface of the casing 1 away from the installation cavity 102 has an installation groove 101; one end of the side-folding body 3 is connected to the outer surface of the casing 1; the other end of the side-folding body 3 is bent toward the installation groove 101; and the other end of the side-folding body 3 is connected to the interior of the installation groove 101.

[0038] The technical solution of this utility model adds an installation groove to facilitate the bending and embedding of the side fold body, thereby effectively reducing the thickness of the protruding side fold body after bending. This reduces the overall width of the soft-pack battery cell and optimizes the material distribution in the area where the side fold body is located. Consequently, it can improve the volumetric energy density, reduce redundant space occupation, avoid edge material accumulation, ensure safety and stability in use, and better adapt to the corresponding assembly space of the terminal, thus improving space utilization.

[0039] Specifically, in some implementations, such as Figure 1 and 2 As shown, the depth of the mounting groove 101 is d, where d satisfies: 0.1mm < d < 0.5mm. That is, d can be 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.49mm, etc.; preferably 0.3mm. This structure, by forming a mounting groove 101 with a suitable indentation, can ensure the assembly stability of the battery cells in the mounting cavity 102, and also ensure the stability of the bending assembly of the side fold 3. The depth is the dimension of the side fold 3 in the direction towards the covering body 1.

[0040] Specifically, in some implementations, such as Figure 1 and 2 As shown in Figures 4, 5, 6, 7, and 8, the side-folding body 3 includes an outer folding segment 31 and an inner folding segment 32 that are stacked and connected to each other. The bending state of the outer folding segment 31 is the same as that of the inner folding segment 32. One end of the outer folding segment 31 is connected to one end of the first covering surface 11, and one end of the inner folding segment 32 is connected to one end of the side cover 13. In other words, this structure ensures the structural sealing performance of the side-folding body 3 by assembling the outer folding segment 31 and the inner folding segment 32, which are stacked and assembled as a whole, thereby ensuring the heat sealing quality. Furthermore, the assembly of the outer folding segment 31 and the inner folding segment 32 with the first covering surface 11 and the side cover 13, respectively, improves the stability of the overall structure and ensures the safety and stability of use.

[0041] Specifically, in some implementations, such as Figure 1 and 2As shown in 4, 5, and 6, the covering body 1 includes a first covering surface 11, a second covering surface 12, and at least one side cover 13; the first covering surface 11 and the second covering surface 12 are arranged side by side; (wherein, the first covering surface 11 is located above the second covering surface 12; or the first covering surface 11 is located below the second covering surface 12);) the two ends of the side cover 13 are respectively connected to the first covering surface 11 and the second covering surface 12; and the mounting cavity 102 is formed between the first covering surface 11, the second covering surface 12, and the side cover 13; and one end of the side folding body 3 is connected to the first covering surface 11 and / or the side cover 13; the mounting groove 101 is provided on the outer surface of the side cover 13 away from the mounting cavity 102. In some embodiments, such as... Figure 2 As shown, there are at least two side covers 13, which are disposed opposite to each other at the two ends between the first covering surface 11 and the second covering surface 12. That is, when the pouch cell is in a heat-sealed state, the side fold 3 is connected to the outer surface of the first covering surface 11 and / or the side cover 13 facing the mounting cavity 102. That is, by bending the side fold 3 towards the side cover 13 for storage, the thickness of the side fold after bending is reduced, thereby reducing the overall width of the pouch cell; thereby increasing the volumetric energy density (ED), reducing redundant space occupation; and ensuring the safety and stability of use.

[0042] Specifically, in some of these implementations, such as Figure 2 As shown, the side cover 13 includes a first vertical encapsulation segment 131, a first horizontal encapsulation segment 132, and a second vertical encapsulation segment 133 connected in sequence; the first vertical encapsulation segment 131 is connected to the first covering surface 11; the first horizontal encapsulation segment 132 is vertically disposed between the first vertical encapsulation segment 131; one side end of the first horizontal encapsulation segment 132 extends toward the mounting cavity 102 and is connected to one side end of the second vertical encapsulation segment 133; the second vertical encapsulation segment 133 is connected to the second covering surface 12; and a mounting groove 101 is formed between the side surface of the first horizontal encapsulation segment 132 away from the mounting cavity 102 and the side surface of the second vertical encapsulation segment 133 away from the mounting cavity 102. In other words, by forming a stepped irregular perforation on the outer surface of the side cover 13, it is easier for the side fold 3 to be bent and stored in the mounting groove 101, thereby reducing the thickness of the side fold after bending, which can reduce the overall width of the soft-pack battery cell; thereby increasing the volumetric energy density (ED), reducing redundant space occupation; and ensuring the safety and stability of use.

[0043] In some implementation methods, such as Figure 2As shown, a first cavity 103 is provided between the first vertical encapsulation section 131, the first horizontal encapsulation section 132, and the first covering surface 11; a second cavity 104 is provided between the second vertical encapsulation section 133 and the second covering surface 12; and the first cavity 103 and the second cavity 104 are interconnected; and a stepped mounting cavity 102 is formed between the first cavity 103 and the second cavity 104. This structure forms a stepped mounting cavity 102 between the first cavity 103 and the second cavity 104 to create an internal stacked irregular-shaped pit configuration; thereby improving the volumetric energy density (ED) of the cell, reducing the internal redundant space occupation; and ensuring the safety and stability of use. In this structure, the length L1 of the first cavity 103 is greater than the length L2 of the second cavity 104; the width W1 of the first cavity 103 is equal to the width W2 of the second cavity 104; and the height h1 of the first cavity 103 is greater than or equal to the height h2 of the second cavity 104 (i.e., the height of the first vertical encapsulation section 131 is greater than or equal to the height of the second vertical encapsulation section 133). This structure can form a stepped vertical nested structure to improve the support stability of the internal battery cells, thereby improving the safety and stability of use.

[0044] Specifically, in the first batch of implementation methods, such as Figure 1 and 2As shown, the side-folding body 3 includes a first vertical bending segment 301, a first horizontal bending segment 302, and a second vertical bending segment 303 connected in sequence. The first horizontal bending segment 302 is bent towards the mounting groove 101 and disposed on the first vertical bending segment 301. One side surface of the second vertical bending segment 303 facing the mounting groove 101 is connected to the second vertical encapsulation segment 133. One side end of the second vertical bending segment 303 is bent towards the first covering surface 11 and disposed on the mounting groove 101. The height h2 of the second vertical encapsulation segment 133 or the second cavity 104 and the height X of the second vertical bending segment 303 satisfy: 0.8mm ≤ X ≤ 1.1mm; and X < h2. That is, X can be 0.81mm, 0.83mm, 0.86mm, 0.89mm, 0.90mm, 0.83mm, 0.95mm, 1.0mm, 1.1mm, etc.; preferably 0.9mm. In other words, the structure achieves a first fold towards the cell body through the first vertical bending section 301 and the first horizontal bending section 302; then, it is embedded into the upper mounting groove 101 through the second vertical bending section 303 to form a second fold. The overlapping area of ​​the first and second fold structures is completely embedded in the stepped platform, i.e., the area of ​​depth d; thus reducing the thickness of the protruding side fold after bending, which can reduce the overall width of the soft-pack cell; thereby increasing the volumetric energy density (ED), reducing redundant space occupation; and ensuring safety and stability in use. Furthermore, an adhesive component 4 is provided between the second vertical bending section 303 and the second vertical encapsulation section 133. Further, the adhesive component 4 is an adhesive (e.g., UV-curable adhesive).

[0045] Specifically, in the second batch of implementation methods, such as Figure 3 As shown, the side-folding body 3 includes a third vertical bending segment 304, a fourth inclined bending segment 305, and a fourth vertical bending segment 306 connected in sequence; the fourth inclined bending segment 305 is inclinedly connected to the third vertical bending segment 304 in the direction of the mounting groove 101; the fourth vertical bending segment 306 is connected to the second vertical encapsulation segment 133 on one side surface facing the mounting groove 101; and one end of the fourth vertical bending segment 306 extends towards the horizontal plane where the second covering surface 12 is located. Further, adhesive components 4 are provided between the side surface of the second covering surface 12 facing the mounting groove 101 and the second vertical encapsulation segment 133, and on the outer surface of the second vertical encapsulation segment 133. Further, the adhesive component 4 is an adhesive (e.g., UV-curable adhesive). The third vertical bending section 304, the fourth inclined bending section 305, and the fourth vertical bending section 306 of the single-sided bending structure are assembled using a UV curing adhesive process or a top adhesive encapsulation process, thereby embedding the bending section with the maximum thickness inside the mounting groove 101, thus achieving a reduction in width and reducing redundant space occupation; and ensuring safety and stability in use.

[0046] Specifically, in the third batch of implementation methods, such as Figure 4 As shown, the side-folding body 3 includes a fifth vertical bending segment 307 and a second horizontal bending segment 308 connected in sequence; the second horizontal bending segment 308 is bent towards the mounting groove 101 and disposed on the fifth vertical bending segment 307; and the second horizontal bending segment 308 is connected to the first horizontal bending segment 302. The second horizontal bending segment 308 and the first horizontal bending segment 302 are provided with an adhesive component 4. Further, the adhesive component 4 is an adhesive (e.g., UV-curable adhesive). This structure is formed by combining the single-sided bending of the fifth vertical bending segment 307 with the horizontally bent second horizontal bending segment 308, and the second horizontal bending segment 308 is embedded inside the mounting groove 101, thereby achieving a reduction in width and minimizing redundant space occupation; and ensuring safety and stability in use.

[0047] Specifically, in other implementations, such as Figure 5 and 6 As shown, the side cover 13 includes a third vertical encapsulation section 136, a second horizontal encapsulation section 135, a first vertical encapsulation section 131, a first horizontal encapsulation section 132, and a second vertical encapsulation section 133 connected in sequence; the third vertical encapsulation section 136 is connected to the first covering surface 11; the third vertical encapsulation section 136 and the second horizontal encapsulation section 135 are vertically arranged; and an assembly groove 105 is provided between the third vertical encapsulation section 136 and the second horizontal encapsulation section 135; the assembly groove 105 and the mounting groove 101 are respectively arranged opposite to each other on both sides of the width direction of the covering body 1; (and Furthermore, the mounting groove 105 is disposed on the outer surface of the cover 1 away from the mounting cavity 102; the first horizontal encapsulation section 132 and the first vertical encapsulation section 131 are vertically disposed between them; one end of the first horizontal encapsulation section 132 extends toward the mounting cavity 102 and is connected to one end of the second vertical encapsulation section 133; the second vertical encapsulation section 133 is connected to the second cover surface 12; and a mounting groove 101 is formed between the side surface of the first horizontal encapsulation section 132 away from the mounting cavity 102 and the side surface of the second vertical encapsulation section 133 away from the mounting cavity 102. In other words, by forming a stepped irregular perforated configuration on the outer surface of the side cover 13, it is beneficial for the side fold 3 to be bent and stored toward the mounting groove 101, so as to reduce the thickness of the side fold after bending, thereby reducing the overall width of the soft-pack cell; thereby increasing the volumetric energy density (ED), reducing redundant space occupation; and ensuring the safety and stability of use.

[0048] Specifically, in the fourth batch of implementation methods, such as Figure 5As shown, the side-folding body 3 includes a sixth vertical bending segment 3092, a third horizontal bending segment 3091, a first vertical bending segment 301, a first horizontal bending segment 302, and a second vertical bending segment 303 connected in sequence. The sixth vertical bending segment 3092 is disposed on the third horizontal bending segment 3091 facing the mounting groove 105. The first horizontal bending segment 302 is bent and disposed on the first vertical bending segment 301 in the direction of the mounting groove 101. One side surface of the second vertical bending segment 303 facing the mounting groove 101 is connected to the second vertical encapsulation segment 133. And one side end of the second vertical bending segment 303 is bent and disposed on the mounting groove 101 in the direction of the first covering surface 11. Furthermore, L1 > the width L4 of the mounting groove 101 > the width L3 of the mounting groove 105. In other words, the structure achieves a first fold towards the cell body through the first vertical bending section 301 and the first horizontal bending section 302; then, it is embedded into the upper mounting groove 101 through the second vertical bending section 303 to form a second fold; simultaneously, the overlapping area of ​​the first and second fold structures is completely embedded into the stepped platform, and the sixth vertical bending section 3092 and the third horizontal bending section 3091 form a stepped fold embedded in the assembly groove 105; thereby reducing the thickness of the protruding side fold after bending, which can reduce the overall width of the soft-pack cell; thus increasing the volumetric energy density (ED), reducing redundant space occupation; and ensuring safety and stability in use. Furthermore, an adhesive component 4 is provided between the second vertical bending section 303 and the second vertical encapsulation section 133. Further, the adhesive component 4 is an adhesive (e.g., UV-curable adhesive).

[0049] Specifically, in the fifth batch of implementation methods, such as Figure 6As shown, the side-folding body 3 includes a sixth vertical bending segment 3092, a third horizontal bending segment 3091, a third vertical bending segment 304, a fourth inclined bending segment 305, and a fourth vertical bending segment 306 connected in sequence. The sixth vertical bending segment 3092 is disposed on the third horizontal bending segment 3091 facing the mounting groove 105. The fourth inclined bending segment 305 is inclinedly connected to the third vertical bending segment 304 in the direction of the mounting groove 101. The side surface of the fourth vertical bending segment 306 facing the mounting groove 101 is connected to the second vertical encapsulation segment 133. And one end of the fourth vertical bending segment 306 extends towards the horizontal plane where the second covering surface 12 is located. Further, adhesive components 4 are provided between the side surface of the second covering surface 12 facing the mounting groove 101 and the second vertical encapsulation segment 133, as well as on the outer surface of the second vertical encapsulation segment 133. Further, the adhesive component 4 is an adhesive (e.g., UV-curable adhesive). Furthermore, L1 > the width of the assembly groove 105, L3 > the width of the mounting groove 101, L4. The third vertical bending segment 304, the fourth inclined bending segment 305, and the fourth vertical bending segment 306 of the single-sided bending structure are assembled using a UV curing adhesive process or a top adhesive encapsulation process, thereby embedding the bending section with the maximum thickness inside the mounting groove 101, thus achieving a reduction in width and reducing redundant space occupation; and ensuring safety and stability in use.

[0050] Specifically, in some other implementations, such as Figure 7 As shown, the side cover 13 includes an inclined encapsulation section 134; the two ends of the inclined encapsulation section 134 are respectively connected to the first covering surface 11 and the second covering surface 12; the mounting groove 101 is disposed between the inclined encapsulation section 134 and the side fold body 3; and the angle between the inclined encapsulation section 134 and its horizontal plane is α, wherein α satisfies: 5°≤α<90°; and can be selected as 5°, 7°, 8°, 9°, 9.5°, 10°, 30°, 40°, 45°, 60°, 70°, 89°, etc. This structure, through the design of the inclined encapsulation section 134 with folded edge embedding, effectively reduces the width of the battery cell, allowing the battery to accommodate more battery cells in a limited space, thereby improving the energy density of the battery.

[0051] Specifically, in the sixth batch of implementation methods, such as Figure 8 As shown, the side-folding body 3 includes a first inclined bending section 3093; one end of the first inclined bending section 3093 is connected to the covering body 1; the other end of the first inclined bending section 3093 extends toward the mounting groove 101. A double-layer adhesive component 4 is provided between the other end of the first inclined bending section 3093 and the side surface of the second covering surface 12 facing the mounting groove 101. Further, the adhesive component 4 is an adhesive (e.g., a UV-curable adhesive).

[0052] Specifically, in the seventh batch of implementation methods, such as Figure 7As shown, the side-folding body 3 includes a first inclined bending section 3093, a third inclined bending section 3095, and a second inclined bending section 3094 connected in sequence. The third inclined bending section 3095 is bent towards the mounting groove 101 and disposed on the first inclined bending section 3093. The second inclined bending section 3094 is connected to the third inclined bending section 3095 on one side surface facing the mounting groove 101. One end of the second vertical bending section 3093 is bent towards the thickness direction of the first covering surface 11 and disposed on the mounting groove 101. The second covering surface 12 of the second inclined bending section 3094 is provided with a double-layer adhesive component 4 on one side surface facing the mounting groove 101. Further, the adhesive component 4 is an adhesive (e.g., UV-curable adhesive). Further still, the height K of the second inclined bending section 3094 is < (h1+h2) / 2. This structure uses a reasonably sized second inclined bending section 3094 to ensure the stability of the bending assembly and to avoid its excessive length from puncturing the top structure.

[0053] The bare battery cell 2 includes a separator 21, a first electrode 22, and a second electrode 23. The separator 21 is disposed between adjacent first electrodes 22 and second electrodes 23, and the first electrodes 22, separator 21, and second electrodes 23 are stacked sequentially to form a stacked structure. The stacked structure is disposed inside the mounting cavity 102 in the pouch cell. Further, the first electrode 22 is either a positive electrode or a negative electrode; the second electrode 23 is either a positive electrode or a negative electrode. The positive electrode includes a positive current collector and a positive active material layer, the positive active material layer being coated on the surface of the positive current collector. The material of the positive current collector can be aluminum, and the positive active material layer includes a positive active material, which can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode sheet includes a negative current collector and a negative active material layer, the negative active material layer being coated on the surface of the negative current collector; the material of the negative current collector can be copper, and the negative active material layer includes a negative active material, which can be carbon or silicon, etc. The separator 21 can be made of PP (polypropylene) or PE (polyethylene), etc.

[0054] The present invention also proposes a secondary battery, which includes a pouch cell. The specific structure of the pouch cell is as described in the above embodiments. Since the present secondary battery adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0055] A rechargeable battery, also known as a secondary battery or accumulator, is a battery that can be recharged after being discharged, allowing the active materials to be reactivated and reused. Utilizing the reversibility of chemical reactions, a new battery can be constructed; that is, after a chemical reaction converts into electrical energy, the electrical energy can be used to repair the chemical system, and then the chemical reaction can be converted back into electrical energy. Therefore, it is called a secondary battery (rechargeable battery). The main types of rechargeable batteries on the market include nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid (or lead-acid) batteries, lithium-ion batteries, and polymer lithium-ion batteries.

[0056] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0057] Based on the disclosure and teachings of the above specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, this utility model is not limited to the specific embodiments described above, and any obvious improvements, substitutions, or modifications made by those skilled in the art based on this utility model are within the protection scope of this utility model. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on this utility model.

Claims

1. A pouch cell, characterized in that: It includes a bare battery cell, a casing, and a side-folding body; the casing has a mounting cavity; the bare battery cell is disposed inside the mounting cavity; the outer surface of the casing away from the mounting cavity has a mounting groove; one end of the side-folding body is connected to the outer surface of the casing; the other end of the side-folding body is bent toward the mounting groove; and the other end of the side-folding body is connected to the interior of the mounting groove.

2. The soft-pack battery cell according to claim 1, characterized in that: The cover includes a first covering surface, a second covering surface, and at least one side cover; the side cover is disposed between the first covering surface and the second covering surface; and the mounting cavity is formed between the first covering surface, the second covering surface, and the side cover; and one end of the side cover is connected to the first covering surface and / or the side cover; the mounting groove is disposed on the outer surface of the side cover away from the mounting cavity.

3. The soft-pack battery cell according to claim 2, characterized in that: The side cover includes a first vertical encapsulation segment, a first horizontal encapsulation segment, and a second vertical encapsulation segment connected in sequence; the first vertical encapsulation segment is connected to the first covering surface; one end of the first horizontal encapsulation segment extends toward the mounting cavity and is connected to one end of the second vertical encapsulation segment; the second vertical encapsulation segment is connected to the second covering surface; and the mounting groove is formed between the side surface of the first horizontal encapsulation segment away from the mounting cavity and the side surface of the second vertical encapsulation segment away from the mounting cavity.

4. The soft-pack battery cell according to claim 3, characterized in that: The side-folding body includes a first vertical bending segment, a first horizontal bending segment, and a second vertical bending segment connected in sequence; the first horizontal bending segment is bent towards the mounting groove and disposed in the first vertical bending segment; one side surface of the second vertical bending segment facing the mounting groove is connected to the second vertical encapsulation segment; and one side end of the second vertical bending segment is bent towards the first covering surface and disposed in the mounting groove; The relationship between the height h2 of the second vertical encapsulation section and the height X of the second vertical bending section satisfies: 0.8mm≤X≤1.1mm; and X<h2.

5. The soft-pack battery cell according to claim 3, characterized in that: The side-folding body includes a third vertical bending segment, an inclined bending segment, and a fourth vertical bending segment connected in sequence; the inclined bending segment is inclinedly connected to the third vertical bending segment in the direction of the mounting groove; the fourth vertical bending segment is connected to the second vertical encapsulation segment on one side surface facing the mounting groove; and one side end of the fourth vertical bending segment extends toward the horizontal plane where the second covering surface is located.

6. The soft-pack battery cell according to claim 4, characterized in that: The side-folding body includes a fifth vertical bending segment and a second horizontal bending segment connected in sequence; the second horizontal bending segment is bent towards the mounting groove and disposed on the fifth vertical bending segment; and the second horizontal bending segment is connected to the first horizontal bending segment.

7. The pouch cell according to any one of claims 4 to 6, characterized in that: The side cover also includes a third vertical encapsulation section and a second horizontal encapsulation section that are connected to each other; the third vertical encapsulation section and the second horizontal encapsulation section are arranged perpendicularly to each other; and an assembly groove is provided between the third vertical encapsulation section and the second horizontal encapsulation section; the assembly groove and the mounting groove are respectively arranged opposite to each other on both sides of the width direction of the cover; and the side folding body includes a sixth vertical bending section and a third horizontal bending section that are connected to each other; the sixth vertical bending section and the third horizontal bending section are arranged perpendicularly to each other and are disposed on the inner wall of the assembly groove.

8. The soft-pack battery cell according to claim 4, characterized in that: The side cover includes an inclined encapsulation section; the two ends of the inclined encapsulation section are respectively connected to the first covering surface and the second covering surface; the mounting groove is disposed between the inclined encapsulation section and the side folding body; and the angle between the inclined encapsulation section and its horizontal plane is α, wherein α satisfies: 5°≤α<90°; The side-folding body includes a first inclined bending section; one end of the first inclined bending section is connected to the covering body; the other end of the first inclined bending section extends toward the mounting groove.

9. The soft-pack battery cell according to claim 8, characterized in that: The side-folding body further includes a third inclined bending section and a second inclined bending section connected in sequence; the third inclined bending section is bent and disposed in the direction of the mounting groove from the first inclined bending section; one side surface of the second inclined bending section facing the mounting groove is connected to the third inclined bending section; and one side end of the second vertical bending section is bent and disposed in the mounting groove in the direction of the thickness of the first covering surface.

10. A secondary battery, characterized in that: Includes the pouch cell as described in any one of claims 1 to 8.

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