Single battery and battery pack

Abstract

The utility model provides a single battery and a battery pack, and the single battery comprises a shell which is provided with a large surface wall, a side surface wall, a top surface wall and a bottom surface wall; the coating film comprises a large surface part, a top surface part, a side surface part and a bottom surface part, the large surface part is used for covering the large surface wall, the top surface part is used for covering the top surface wall, the bottom surface part is used for covering the bottom surface wall, and the side surface part is used for covering the side surface wall; the side face part is at least partially folded at the side face wall, a notch is formed in the area, adjacent to the bottom face part, of the side face part, and an opening of the notch is arranged back to the bottom face part, so that the number of folded layers of the side face part at the side face wall does not exceed three. According to the utility model, the number of overlapped layers of the coating film on the side wall of the shell is at most three, so that the layer difference is reduced, and the assembly of the single battery in a battery pack or a battery pack is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a single cell and a battery pack. Background Art

[0002] The single cell includes a shell and a coating film wrapped around the shell. The coating film is used to insulate the shell and protect the shell. The existing U-shaped coating film overlaps at most five layers on the same side wall of the shell, and at least two layers, which makes the layer difference of the coating film on the same side wall of the shell too large, affecting the assembly of the single cell in the battery pack or battery pack. Utility Model Content

[0003] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a single cell with a small coating layer difference, which is convenient for assembly in a battery pack or battery package.

[0004] Another object of the present invention is to provide a battery pack with high safety and small assembly tolerance of single cells.

[0005] The embodiments of the present invention are implemented by the following technical solutions:

[0006] A single battery comprises: a shell having a large surface wall, a side surface wall, a top surface wall and a bottom surface wall; a covering film comprising a large surface portion, a side surface portion and a bottom surface portion, wherein the large surface portion is used to cover the large surface wall, the bottom surface portion is used to cover the bottom surface wall, and the side surface portion is used to cover the side wall; the side surface portion is at least partially folded at the side surface wall, and a notch is provided in the area of ​​the side surface portion adjacent to the bottom surface portion, and the opening of the notch is arranged away from the bottom surface portion, so that the number of folding layers of the side surface portion at the side surface wall does not exceed three; the side surface portion comprises a first transverse folding portion and a first longitudinal folding portion connected to each other, wherein the first transverse folding portion is connected to the large surface portion and extends from the large surface wall to the side surface wall, and the first longitudinal folding portion is connected to the bottom surface portion and extends from the bottom surface wall to the side surface wall; the two notches are arranged relative to each other with respect to the first longitudinal folding portion along the thickness direction of the shell; the thickness direction is the relative direction of the two large surface walls on the shell.

[0007] On the one hand, the notch here facilitates the smooth bending of the side portion to fit to the side wall, and on the other hand, it can reduce the number of layers of the side portion folded at the side wall to a maximum of three layers, which reduces the layer difference of the coating film at the side wall, which is beneficial to improving the flatness of the side wall of the shell of the single cell after the coating film is attached, thereby facilitating the assembly of the single cell in the battery pack or battery pack; the notch is arranged in the area of ​​the side portion adjacent to the bottom portion, which can prevent the coating film on the side wall from tearing when the single cell expands in the thickness direction of the shell, thereby improving the safety of the single cell; in addition, the structural design of the side portion at least partially folded at the side wall can increase the thickness of the coating film at the side wall, thereby ensuring the structural strength of the coating film at the side wall.

[0008] A battery pack includes the above-mentioned single cell, wherein a plurality of the single cells are stacked. Based on the safety of the single cell, the safety of the battery pack is improved, and the single cell is easy to assemble in the battery pack with a small assembly tolerance. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0010] Figure 1 A schematic diagram of the structure of the coating film provided in an embodiment of the utility model in a flat state;

[0011] Figure 2 A schematic diagram of a first three-dimensional structure of a housing provided in an embodiment of the utility model;

[0012] Figure 3 A second three-dimensional structural schematic diagram of a housing provided in an embodiment of the utility model;

[0013] Figure 4 A schematic diagram of a three-dimensional structure of a single cell provided by an embodiment of the utility model, in which a covering film is in a semi-covering state;

[0014] Figure 5 A schematic diagram of a three-dimensional structure of a single cell in a covered state provided by an embodiment of the utility model;

[0015] Figure 6 A schematic diagram of a three-dimensional structure of another single cell provided by an embodiment of the utility model, in which the covering film is in a semi-covering state;

[0016] Figure 7A schematic diagram of the three-dimensional structure of another single cell provided by an embodiment of the utility model, in which the covering film is in a covering state.

[0017] Icons: 100, shell; 101, large wall; 102, side wall; 103, top wall; 104, bottom wall; 105, pole; 200, coating; 21, bottom portion; 211, notch; 22, large portion; 23, top portion; 24, side portion; 241, first horizontal fold portion; 242, first longitudinal fold portion; 2421, overlapping portion; a, first fold; b, second fold; c, third fold; d, fourth fold; e, fifth fold; f, sixth fold. DETAILED DESCRIPTION

[0018] For better understanding and implementation, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0019] In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc. indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0021] Please refer to Figures 1 to 7 A single cell battery includes a housing 100 and a coating film 200, specifically Figure 2 and Figure 3 As shown, the shell 100 is in the shape of a rectangular parallelepiped, and the shell 100 has a large wall 101, a side wall 102, a top wall 103 and a bottom wall 104; the X direction is the height direction of the single battery, that is, the shell 100, the top wall 103 is on the upper side of the shell 100 in the height direction, and the bottom wall 104 is on the lower side in the height direction. The large wall 101 and the side wall 102 on the circumferential side of the shell 100 in the height direction are adjacent to each other, the area of ​​the large wall 101 is larger than the area of ​​the side wall 102, and the pole 105 is arranged on the top wall 103.

[0022] The covering film 200 here is used to cover the outer wall of the shell 100 to insulate and protect the shell 100. Therefore, accordingly, the covering film 200 includes a large surface portion 22, a top surface portion 23, a side surface portion 24 and a bottom surface portion 21, wherein the large surface portion 22 is used to cover the large surface wall 101, the top surface portion 23 is used to cover the top surface wall 103, the bottom surface portion 21 is used to cover the bottom surface wall 104, and the side surface portion 24 is used to cover the side wall 102; the side surface portion 24 is at least partially folded at the side wall 102, and a notch 211 is opened in the area of ​​the side surface portion 24 adjacent to the bottom surface portion 21, and the opening of the notch 211 is set back to the bottom surface portion 21, so that the number of folded layers of the side surface portion 24 at the side wall 102 does not exceed three layers.

[0023] The notch 211 here, on the one hand, facilitates the side portion 24 to be bent smoothly to fit to the side wall 102, and on the other hand, it can reduce the number of layers of the side portion 24 folded at the side wall 102 to a maximum of three layers, which reduces the layer difference of the coating film 200 at the side wall 102, which is beneficial to improve the flatness of the side wall 102 of the shell 100 of the single battery after the coating film 200 is attached, thereby facilitating the assembly of the single battery in the battery pack or battery pack; in addition, as Figures 4 to 7 As shown, the side wall 102 is mainly covered by the area of ​​the side part 24 adjacent to the large surface 22. The notch 211 is set in the area of ​​the side part 24 adjacent to the bottom surface 21 instead of in the area of ​​the side part 24 adjacent to the large surface 22. This ensures that when the single battery expands in the thickness direction of the shell 100, the area of ​​the side part 24 adjacent to the large surface 22 has a larger contact area with the battery side wall 102, so that it can better resist the pulling force applied to the covering film 200 by the expansion of the single battery. The structural strength is high, and the covering film on the side wall 102 can be effectively prevented. The film 200 is torn, which improves the safety of the single cell; and, when the single cell is assembled and used in a battery pack or a battery package, the bottom wall 104 is matched with a structural adhesive or a cold plate, the top wall 103 is mostly matched with a CCS assembly, and the large walls 101 of adjacent single cells are fitted to each other. Therefore, the side walls 102 are more susceptible to wear and tear from other components in the battery pack or the battery package. In this embodiment, the structural design of the side portion 24 at least partially folded at the side wall 102 can increase the thickness of the coating film 200 at the side wall 102, thereby ensuring the structural strength of the coating film 200 at the side wall 102.

[0024] In this embodiment, the thickness direction of the shell 100 is the relative direction of the two large walls 101 on the shell 100 .

[0025] like Figure 1 , Figure 4 and Figure 6As shown, the side surface portion 24 includes a first transverse folding portion 241 and a first longitudinal folding portion 242 connected to each other, wherein the first transverse folding portion 241 is connected to the large surface portion 22 and extends from the large surface wall 101 to the side surface wall 102, and the first longitudinal folding portion 242 is connected to the bottom surface portion 21 and extends from the bottom surface wall 104 to the side surface wall 102; the two notches 211 are arranged relative to the first longitudinal folding portion 242 along the thickness direction of the shell 100. Preferably, the two notches 211 are arranged symmetrically about the first longitudinal folding portion 242 along the thickness direction of the shell 100. Specifically, as Figure 1 As shown, when the covering film 200 is in a flat state, the covering film 200 is in a rectangular shape. In the length direction of the covering film 200, the two large face portions 22 are symmetrically arranged about a bottom face portion 21; in the width direction of the covering film 200, the two first transverse folding portions 241 are symmetrically arranged about a corresponding large face portion 22, and the two first longitudinal folding portions 242 are symmetrically arranged about a bottom face portion 21. In this embodiment, as Figure 1 As shown, the Y direction is the length direction of the covering film 200, and the Z direction is the width direction of the covering film 200. On the same side of the width direction of the covering film 200, the two first transverse folding portions 241 are symmetrically arranged about the first longitudinal folding portion 242. The symmetrical arrangement of the structures of each region of the covering film 200 facilitates the covering operation of the covering film 200 on the housing 100. In this embodiment, the first transverse folding portion 241 and the first longitudinal folding portion 242 are integrally connected. In another embodiment, the first transverse folding portion 241 and the first longitudinal folding portion 242 may also be bonded.

[0026] like Figure 1 , Figure 4 and Figure 6 As shown, further, the bottom portion 21 is connected to the large portion 22, with a first fold a therebetween, and a second fold b is therebetween the first transverse fold 241 and the first longitudinal fold 242; when the bottom portion 21, the large portion 22 and the side portion 24 are coplanar, the first fold a and the corresponding second fold b are collinear; the edge of the notch 211 close to the first transverse fold 241 is collinear with the second fold b. Figure 4 and Figure 6 As shown, the edge of the notch 211 close to the first transverse fold portion 241 is colinear with the second fold b. After the first transverse fold portion 241 is folded and attached to the side wall 102, the edge of the first transverse fold portion 241 on the side facing the bottom surface portion 21 is flush. When the first longitudinal fold portion 242 is folded and attached to the side, no overlapping occurs in the area of ​​the first transverse fold portion 241, thereby ensuring that the number of overlapping layers of the coating film 200 at the side wall 102 does not exceed three.

[0027] The first longitudinal fold portion 242 here is a region of the side surface portion 24 adjacent to the bottom surface portion 21 .

[0028] When using, Figure 4 and Figure 6As shown, first, the housing 100 is placed on the covering film 200, and the bottom wall 104 is attached to the bottom surface 21; then, the two large surface parts 22 symmetrically arranged about the bottom surface 21 are folded upward to attach to the corresponding large surface walls 101; then, the first transverse folding part 241 is horizontally folded to attach to the corresponding side wall 102. During this process, the area on the first longitudinal folding part 242 that is adjacent to the first transverse folding part 241 and the notch 211 is folded and attached to the area on the first longitudinal folding part 242 that is adjacent to the bottom surface 21 and the notch 211 to form the overlapping part 2421; finally, the first longitudinal folding part 242 is folded upward to attach to the side wall 102. In this embodiment, the overlapping part 2421 is a two-layer covering film 200, which overlaps with the corresponding first transverse folding part 241 after being attached to the side surface 24, so that the covering film 200 in this area is three-layer.

[0029] like Figure 4 As shown, it should be noted that, on the side wall 102, among the two first transverse folds 241, the overlapping portion 2421 of one transverse fold and the other transverse fold does not overlap, thereby ensuring that the number of layers of the coating film 200 at the side wall 102 does not exceed three.

[0030] Optionally, the notch 211 is in any of a square, a triangle, a trapezoid or a U-shape. In this embodiment, preferably, the notch 211 is in a square shape to facilitate cutting and processing of the coating film 200.

[0031] like Figure 1 As shown, there is a third fold c between the first longitudinal fold 242 and the bottom surface 21, and there is a fourth fold d in the first longitudinal fold 242. One end of the fourth fold d is located at the intersection of the second fold b and the third fold c, and the other end extends to the bottom of the notch 211; the fourth fold d is not colinear with the second fold b. In this embodiment, the area defined by the second fold b, the fourth fold d and the bottom edge of the notch 211 is a layer of the overlapping portion 2421. Figure 4As shown, the area defined by the second fold b, the fourth fold d and the bottom edge of the notch 211 determines the area of ​​the overlapping portion 2421. Specifically, the area defined by the second fold b, the fourth fold d and the bottom edge of the notch 211 is equal to the area of ​​the overlapping portion 2421. Therefore, in this embodiment, the area defined by the second fold b, the fourth fold d and the bottom edge of the notch 211 is equal to the aforementioned overlapping portion 2421. Optionally, the angle between the fourth fold d and the third fold c is 10°-80°. Preferably, the angle between the fourth fold d and the third fold c is 45°. The angle between the fourth fold d and the third fold c is 45°. At this time, when the first transverse fold portion 241 is folded and attached to the side wall surface, the second fold b and the edge of the first transverse fold portion 241 facing the bottom surface portion 21 are parallel to the third fold c. Under ideal conditions (the thickness of the coating film 200 is negligible), the second fold b and the edge of the first transverse fold portion 241 facing the bottom surface portion 21 coincide with the third fold c, thereby ensuring that the first transverse fold portion 241 will not be partially overlapped during the folding of the first longitudinal fold portion 242 to the side wall 102.

[0032] like Figure 4 and Figure 5 As shown, in some embodiments, the bottom surface 21 is symmetrically provided with two large surface portions 22 along the thickness direction of the housing 100, and the large surface portions 22 are provided corresponding to the first transverse folding portions 241; in the same side wall 102, the two first transverse folding portions 241 provided opposite to each other at least partially overlap. It should be noted that, among the two first transverse folding portions 241, the overlapping portion 2421 adjacent to the other transverse folding portion does not overlap, and the minimum distance between the two is not less than 2 mm.

[0033] like Figure 6 and Figure 7 As shown, in another embodiment, in the same side wall 102, the two first transverse folding portions 241 arranged opposite to each other do not overlap. In this embodiment, the side portion 24 needs to be provided with a side film for fitting and covering the area between the two first transverse folding portions 241, and the side film is defined as a compensation film (not shown in the figure), which is used to cover the area between the two first transverse folding portions 241 on the side wall 102, and the compensation film at least partially overlaps with the first transverse folding portion 241; in the thickness direction of the housing 100, the compensation film does not overlap with the overlapping portion 2421, and the minimum distance between the two is not less than 2 mm.

[0034] In this embodiment, there is a fifth fold e between the top surface 23 and the large surface 22. After the large surface wall 101 and the side wall 102 are covered, the shape of the single battery is as follows: Figure 4 and Figure 6 As shown, at this time, the top surface portion 23 is folded along the fifth fold e to fit to the top surface wall 103, as shown in FIG. Figure 5 and Figure 7 Specifically, Figure 1 As shown, the overlapping area between the first transverse fold portion 241 and the adjacent top surface portion 23 is stacked when attached to the top surface wall 103, and the number of layers does not exceed three.

[0035] In this embodiment, there is a sixth fold f between the large face portion 22 and the first transverse fold portion 241. When in use, the large face portion 22 is folded along the first fold a relative to the bottom face portion 21 to fit to the large face wall 101; the first transverse fold portion 241 is folded along the sixth fold f relative to the large face portion 22, and the first transverse fold portion 241 is folded along the second fold b relative to the first longitudinal fold portion 242 to fit to the side wall 102; the first longitudinal fold portion 242 is folded along the third fold c relative to the bottom face portion 21 to fit to the side wall 102.

[0036] In this embodiment, the coating film 200 is an insulating film. Optionally, the coating film 200 is a PI film or a PP film.

[0037] This embodiment also provides a battery pack, including the above-mentioned single cell, wherein a plurality of single cells are stacked. Based on the safety of the single cell, the safety of the battery pack is improved, and the single cell is easy to assemble in the battery pack, and the assembly tolerance is small; at the same time, the number of layers of the coating film 200 on the side wall 102 of the single cell is small, which can improve the space utilization rate in the battery pack.

[0038] The technical means disclosed in the solution of the utility model are not limited to the technical means disclosed in the above-mentioned implementation mode, but also include technical solutions composed of any combination of the above technical features. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the utility model, and these improvements and modifications are also regarded as the protection scope of the utility model.

Claims

1. A single cell battery, characterized in that: include: The housing (100) has a large wall (101), side walls (102), a top wall (103) and a bottom wall (104); A covering film (200) comprising a large surface portion (22), a side surface portion (24) and a bottom surface portion (21), wherein the large surface portion (22) is used to cover the large surface wall (101), the bottom surface portion (21) is used to cover the bottom surface wall (104), and the side surface portion (24) is used to cover the side surface wall (102); The side surface portion (24) is at least partially folded at the side wall (102), a notch (211) is provided in a region of the side surface portion (24) adjacent to the bottom surface portion (21), and the opening of the notch (211) is arranged away from the bottom surface portion (21), so that the number of folded layers of the side surface portion (24) at the side wall (102) does not exceed three; The side surface portion (24) comprises a first transverse folding portion (241) and a first longitudinal folding portion (242) connected to each other, wherein: The first transverse folding portion (241) is connected to the large surface portion (22) and extends from the large surface wall (101) to the side wall (102); the first longitudinal folding portion (242) is connected to the bottom surface portion (21) and extends from the bottom surface wall (104) to the side wall (102); The two notches (211) are arranged opposite to each other along the thickness direction of the shell (100) and relative to the first longitudinal folding portion (242); The thickness direction is the relative direction of the two large surface walls (101) on the shell (100).

2. The single cell according to claim 1, characterized in that: The bottom surface portion (21) is connected to the large surface portion (22), and a first fold (a) is formed between the two, and a second fold (b) is formed between the first transverse fold portion (241) and the first longitudinal fold portion (242); When the bottom surface (21), the large surface (22) and the side surface (24) are coplanar, the first fold (a) and the corresponding second fold (b) are colinear; The edge of the notch (211) close to the first transverse fold (241) is colinear with the second fold (b).

3. The single cell according to claim 1 or 2, characterized in that: The notch (211) is in any of a square, triangle, trapezoid or U shape.

4. The single cell according to claim 2, characterized in that: A third fold (c) is provided between the first longitudinal fold (242) and the bottom surface (21), a fourth fold (d) is provided inside the first longitudinal fold (242), one end of the fourth fold (d) is located at the intersection of the second fold (b) and the third fold (c), and the other end extends to the bottom of the notch (211); The fourth fold (d) is not colinear with the second fold (b).

5. The single cell according to claim 4, characterized in that: The angle between the fourth fold (d) and the third fold (c) is 10°-80°.

6. The single cell according to claim 1, characterized in that: The bottom surface (21) is symmetrically provided with two large surface portions (22) along the thickness direction of the shell (100), and the large surface portions (22) are provided corresponding to the first transverse folding portion (241); In the same side wall (102), two first transverse folding portions (241) arranged opposite to each other at least partially overlap.

7. The single cell according to claim 1, characterized in that: The bottom surface (21) is symmetrically provided with two large surface portions (22) along the thickness direction of the shell (100), and the large surface portions (22) are provided corresponding to the first transverse folding portion (241); In the same side wall (102), two first transverse folding portions (241) arranged opposite to each other do not overlap.

8. The single cell according to claim 5, characterized in that: The area defined between the second fold (b), the fourth fold (d) and the bottom edge of the notch (211) is the overlapping portion (2421); On the same side wall (102), when the first transverse folding portion (241) and the first longitudinal folding portion (242) are both attached to the side wall (102), the overlapping portion (2421) adjacent to one of the first transverse folding portions (241) and the other first transverse folding portion (241) does not overlap.

9. The single cell according to claim 8, characterized in that: The bottom surface (21) is symmetrically provided with two large surface portions (22) along the thickness direction of the shell (100), and the large surface portions (22) are provided corresponding to the first transverse folding portion (241); In the same side wall (102), two first transverse folding portions (241) arranged opposite to each other at least partially overlap; In the thickness direction of the shell (100), the overlapping portion (2421) adjacent to one of the first transverse folding portions (241) and the other first transverse folding portion (241) do not overlap, and the minimum distance between the two is not less than 2 mm.

10. The single cell according to claim 8, characterized in that: The bottom surface (21) is symmetrically provided with two large surface portions (22) along the thickness direction of the shell (100), and the large surface portions (22) are provided corresponding to the first transverse folding portion (241); In the same side wall (102), two first transverse folding portions (241) arranged opposite to each other do not overlap; It also includes a compensation film, the compensation film is used to cover the area between the two first transverse folding portions (241) on the side wall (102), and the compensation film at least partially overlaps with the first transverse folding portion (241); In the thickness direction of the shell (100), the compensation film and the overlapping portion (2421) do not overlap, and the minimum distance between the two is not less than 2 mm.

11. The single cell according to claim 1, characterized in that: The covering film (200) further comprises a top surface portion (23), wherein the top surface portion (23) is used to cover the top surface wall (103).

12. The single cell according to claim 1, characterized in that: The two notches (211) are symmetrically arranged along the thickness direction of the shell (100) and about the first longitudinal folding portion (242).

13. A battery pack, characterized in that: It comprises a single cell as described in any one of claims 1 to 12, wherein a plurality of the single cells are stacked.

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