Battery

Abstract

The utility model discloses a battery which is applied to the technical field of lithium ion batteries. According to the utility model, the stress release port is arranged on the bottom corner coating area of the insulating film, and the stress release port is arranged in the range that the two adjacent second side surface coating areas are folded to coincide with the two overlapping areas, so that bubbles generated by extrusion are effectively discharged from the stress release port in the process that the compression roller is attached to the insulating film; and therefore, the probability of wrinkles and bubbles of side base angles is reduced, and the film coating yield is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of lithium ion battery, especially a battery. BACKGROUND

[0002] Lithium ion battery has high energy density, long cycle and other advantages and is widely used in energy storage cabinet and as clean energy to provide power for automobile etc.

[0003] The common film coating process at present has a return type film coating and U-shaped film coating. The return type film coating process is: coating one side, coating large surface, coating the other side, cutting bottom film and top film, coating bottom film, folding top film and coating bottom long film, hot pressing, and pasting insulating sheet. The U-shaped film coating process is: coating bottom surface first, coating large surface second, cutting two side films (or canceling cutting), coating two side films, coating bottom side short film, hot pressing top, and pasting insulating sheet.

[0004] The existing process has an overlapping area, which is easy to wrinkle and bubble, reduces the bonding strength, damages the waterproof and insulating performance of the insulating film, and brings safety risks. At the same time, in order to wrap the entire cell with the insulating film, the existing film coating process generally coats the large surface first, and the insulating film of a certain length is extended on both sides of the large surface for wrapping the side surface. SUMMARY

[0005] Therefore, the utility model aims to provide a battery to solve the problem that the bottom corner overlapping area of the insulating film is easy to wrinkle and bubble.

[0006] To solve the above technical problems, the utility model provides a battery, which comprises an insulating film and a shell.

[0007] The bottom surface coating area wraps the bottom surface.

[0008] The first side surface coating area wraps the first side surface.

[0009] The second side covering region wraps the second side; the second side covering region comprises a non-overlapping region and an overlapping region, and the overlapping regions of the second side covering regions adjacent to each other overlap on the second side;

[0010] The bottom corner covering region wraps the second side covering region; the bottom corner covering region comprises a stress release port, and the stress release port is arranged in the overlapping region.

[0011] Optionally, the overlapping region and the non-overlapping region extend along a first direction and are arranged in sequence along a second direction.

[0012] The stress release port extends from one side of the bottom corner covering region away from the bottom surface covering region to the bottom surface covering region along the first direction.

[0013] Optionally, the bottom corner covering region further comprises two bottom corner diagonal crease lines and two cuts.

[0014] The cuts extend from one side of the bottom corner covering region away from the bottom surface covering region to the bottom surface covering region along the first direction, and are arranged on both sides of the stress release port along the second direction, respectively.

[0015] The bottom corner diagonal crease lines extend from the vertex connecting the bottom corner covering region and the bottom surface covering region to the end of the cut adjacent to the bottom surface covering region.

[0016] The bottom corner covering region is divided into a bottom corner covering overlapping region and four side covering overlapping regions by the stress release port, the cuts and the bottom corner diagonal crease lines.

[0017] The two side covering overlapping regions adjacent to the second side covering region both extend along the second direction, wrap the second side covering region, and partially overlap.

[0018] The bottom corner covering overlapping region wraps the two side covering overlapping regions adjacent to the second side covering region.

[0019] The two side covering overlapping regions not adjacent to the second side covering region both extend along the first direction and wrap the second side covering region.

[0020] Optionally, the battery satisfies a first relationship:

[0021] ;

[0022] In the formula, W represents the length of the cut, T represents the thickness of the shell, and L represents the width of the non-overlapping region.

[0023] Optionally, the battery satisfies a second relationship:

[0024] ;

[0025] wherein W1 represents the distance from the end of the stress release port close to the bottom surface cladding region to the bottom surface cladding region, and W represents the length of the cutout.

[0026] Optionally, the battery satisfies a third relationship:

[0027] ;

[0028] wherein W2 represents the distance from the end of the cutout close to the bottom surface cladding region to the bottom surface cladding region, and W represents the length of the cutout.

[0029] Optionally, the battery satisfies a fourth relationship:

[0030] ;

[0031] wherein W1 represents the distance from the end of the stress release port close to the bottom surface cladding region to the bottom surface cladding region, and W2 represents the distance from the end of the cutout close to the bottom surface cladding region to the bottom surface cladding region.

[0032] Optionally, the battery satisfies a fifth relationship:

[0033] ;

[0034] wherein L1 represents the distance from the cutout to the side of the bottom corner cladding region close to the second side surface cladding region, and L represents the width of the non-overlapping region.

[0035] Optionally, the battery satisfies a sixth relationship:

[0036] ;

[0037] wherein L1 represents the distance from the cutout to the side of the bottom corner cladding region close to the second side surface cladding region.

[0038] Optionally, the insulating film further comprises two top surface first cladding regions and four top surface second cladding regions;

[0039] The top surface first cladding region wraps the edge of the top surface close to the first side surface; the top surface first cladding region is connected to the side of the first side surface cladding region away from the bottom surface cladding region;

[0040] The top surface second cladding region wraps the edge of the top surface close to the second side surface; the top surface second cladding region is connected to both the top surface first cladding region and the second side surface cladding region.

[0041] As can be seen, the battery provided by this utility model provides a stress relief port on the bottom corner covering area of ​​the insulating film, and the stress relief port is located within the range where the two adjacent second side covering areas are folded to overlap. In this way, during the process of the pressure roller bonding the insulating film, the air bubbles generated by the extrusion are effectively discharged from the stress relief port, thereby reducing the probability of side corner wrinkles and air bubbles and improving the coating yield. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0043] Figure 1 A schematic diagram showing the unfolded state of an insulating film provided in an embodiment of this utility model;

[0044] Figure 2 This is a partial schematic diagram of region A in an insulating film provided by an embodiment of the present invention;

[0045] Figure 3 and Figure 4 A schematic flowchart of a coating process provided for an embodiment of this utility model;

[0046] Figure 5 A schematic diagram of the structure of a battery provided in an embodiment of this utility model;

[0047] Figure 6 A partial schematic diagram of a battery provided for an embodiment of this utility model;

[0048] Figures 7 to 9 A schematic diagram of the housing dimensions provided for an embodiment of this utility model;

[0049] Figure 10 A schematic diagram of the cut position provided for an embodiment of this utility model;

[0050] Figure 11 This is a schematic diagram of a cut size provided for an embodiment of the present utility model.

[0051] The annotations in the attached figures are explained as follows:

[0052] 1-insulation film; 2-housing; 11-bottom crease line; 12-side crease line; 13-top crease line; 14-bottom corner diagonal crease line; 15-stress release port; 16-cutout; 21-bottom covering area; 22-first side covering area; 23-second side covering area; 24-bottom corner covering area; 241-bottom corner covering overlapping area; 242-side covering overlapping area; 251-top first covering area; 252-top second covering area; 31-five-layer overlapping area; 32-first three-layer overlapping area; 41-second three-layer overlapping area; 42-two-layer overlapping area;

[0053] M-width of the housing; T-thickness of the housing; H-height of the housing;

[0054] L-width of the non-overlapping area / distance from the overlapping area to the side edge of the housing;

[0055] L1-distance from the cutout to the side of the bottom corner covering area close to the second side covering area / distance from the cutout to the side edge of the housing;

[0056] L2-distance from the stress release port to the side of the bottom corner covering area close to the second side covering area / distance from the stress release port to the bottom side edge of the housing;

[0057] W-length of the cutout / length of the area in the bottom corner covering area that is not covered by the side covering overlapping area;

[0058] W1-distance from the end of the stress release port close to the bottom covering area to the bottom covering area / distance from the end of the stress release port close to the bottom covering area to the bottom side edge of the housing;

[0059] W2-distance from the end of the cutout close to the bottom covering area to the bottom covering area / distance from the end of the cutout close to the bottom covering area to the bottom side edge of the housing. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme of the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0061] Please refer to Figures 1 to 11The utility model discloses a kind of batteries, can include: insulating film 1 and shell 2;Shell 2 includes a bottom surface, oppositely arranged two first side surfaces, oppositely arranged two second side surfaces and a top surface;Insulating film 1 includes a bottom surface coating area 21, two first side surface coating area 22, four second side surface coating area 23 and two bottom corner coating area 24;

[0062] Bottom surface coating area 21 wraps bottom surface;

[0063] First side surface coating area 22 wraps first side surface;

[0064] Second side surface coating area 23 wraps second side surface;Second side surface coating area 23 includes non-overlapping area and overlapping area, and the overlapping area of adjacent second side surface coating area 23 overlaps on second side surface;

[0065] Bottom corner coating area 24 wraps second side surface coating area 23;Bottom corner coating area 24 includes stress release port 15, and stress release port 15 is arranged in overlapping area.

[0066] It needs to be explained that insulating film 1 in the embodiment will be disconnected at stress release port 15, and the bubble generated by extrusion can be effectively discharged from the disconnected position in the process that pressure roller is attached insulating film 1.

[0067] The embodiment does not limit the specific arrangement mode of stress release port 15, as long as stress release port 15 is arranged in overlapping area, for example, overlapping area and non-overlapping area can extend along first direction, and sequentially arranged along second direction;

[0068] Stress release port 15 can extend from the side of bottom corner coating area 24, which is away from bottom surface coating area 21, to bottom surface coating area 21 along first direction.

[0069] It needs to be explained that first direction indicates the height direction of shell 2 in the embodiment;Second direction indicates the thickness direction of shell 2.

[0070] Further, in order to realize complete coating to the corner position of shell 2, bottom corner coating area 24 can also include two bottom corner diagonal crease lines 14 and two cutouts 16 in the embodiment;

[0071] Cutout 16 extends from the side of bottom corner coating area 24, which is away from bottom surface coating area 21, to bottom surface coating area 21 along first direction, and is respectively arranged at the two sides of stress release port 15 along second direction;

[0072] Bottom corner diagonal crease line 14 extends from the vertex of bottom corner coating area 24 and bottom surface coating area 21 to the end of adjacent cutout 16, which is close to bottom surface coating area 21;

[0073] The bottom corner covering area 24 is divided into a bottom corner covering overlap area 241 and four side surface covering overlap areas 242 by the stress release port 15, the cutout 16 and the bottom corner oblique crease line 14;

[0074] The two side surface covering overlap areas 242 adjacent to the second side surface covering area 23 extend along the second direction and wrap the second side surface covering area 23, and partially overlap;

[0075] The bottom corner covering overlap area 241 wraps the two side surface covering overlap areas 242 adjacent to the second side surface covering area 23.

[0076] The two side surface covering overlap areas 242 not adjacent to the second side surface covering area 23 extend along the first direction and wrap the second side surface covering area 23.

[0077] Further, in order to realize complete covering of the top surface edge of the shell 2, the insulating film 1 in the embodiment can further include two top surface first covering areas and four top surface second covering areas.

[0078] The top surface first covering area wraps the edge of the top surface close to the first side surface; the top surface first covering area is connected with the side of the first side surface covering area away from the bottom surface covering area.

[0079] The top surface second covering area wraps the edge of the top surface close to the second side surface; the top surface second covering area is connected with the top surface first covering area and the second side surface covering area.

[0080] In order to make the utility model more convenient to understand, the utility model embodiment provides an insulating film in an unfolded state, as shown in the figure. Figure 1 The insulating film 1 can include two bottom surface crease lines 11, two side surface crease lines 12 and two top surface crease lines 13; the bottom surface crease lines 11 extend through the insulating film 1 along a third direction and are sequentially arranged along a fourth direction; the side surface crease lines 12 extend through the insulating film 1 along the fourth direction and are sequentially arranged along the third direction; the second direction is perpendicular to the first direction; the top surface crease lines 13 extend through the insulating film 1 along the third direction and are sequentially arranged along the fourth direction; the bottom surface crease lines 11 are located between the two top surface crease lines 13;

[0081] The insulating film 1 is divided into a bottom surface covering area 21, two first side surface covering areas 22, four second side surface covering areas 23 and two bottom corner covering areas 24 by the bottom surface crease lines 11 and the side surface crease lines 12; the two bottom corner covering areas 24 are respectively located on both sides of the bottom surface covering area 21 along the third direction; the two first side surface covering areas 22 are respectively located on both sides of the bottom surface covering area 21 along the fourth direction; the second side surface covering area 23 is located in the region adjacent to the bottom corner covering area 24 and the first side surface covering area 22.

[0082] The insulating film 1 is divided into two top surface first covering areas 251 and four top surface second covering areas 252 by top surface crease lines 13 and side surface crease lines 12; the two top surface first covering areas 251 are respectively located on the side of the two first side covering areas 22 away from the bottom covering area 21; the top surface second covering areas 252 are located in the area adjacent to the top surface first covering areas 251 and the second side covering areas 23;

[0083] The second side covering area 23 includes a non-overlapping area and an overlapping area; the overlapping area and the non-overlapping area extend along the fourth direction and are arranged sequentially in a direction away from the first side covering area 22.

[0084] The bottom corner covering area 24 includes two bottom corner oblique crease lines 14, a stress relief opening 15, and two cuts 16. The stress relief opening 15 and the cuts 16 extend from the side of the bottom corner covering area 24 away from the bottom covering area 21 towards the bottom covering area 21 along a third direction, and the two cuts 16 are respectively located on both sides of the stress relief opening along a fourth direction. The insulating film 1 is broken at the stress relief opening 15 and the cuts 16. The distance of the stress relief opening 15 to the side of the bottom corner covering area 24 near the second side covering area 23 is greater than the width of the non-overlapping area, so as to ensure that when the insulating film 1 is in use, the stress relief opening 15 can be located in the overlapping area of ​​the second side. The bottom corner oblique crease line 14 extends from the vertex connecting the bottom corner covering area 24 and the bottom covering area 21 to the end of the adjacent cut 15 near the bottom covering area 21. Among them, the third direction represents the width direction of the insulating film 1 in the unfolded state; the fourth direction represents the length direction of the insulating film 1 in the unfolded state.

[0085] It should be noted that, as Figure 2 As shown, in this embodiment, the bottom corner covering area 24 is divided into a bottom corner covering overlapping area 241 and four side covering overlapping areas 242 by the cut 16 and the bottom corner diagonal crease line 14. The bottom corner covering overlapping area 241 is located on the side of the bottom corner covering area 24 closest to the bottom covering area 21. The side covering overlapping areas 242 are arranged sequentially along the fourth direction. While folding the second side covering area 23 along the side crease line 12, the side covering overlapping areas 242 adjacent to the second side covering area 23 are folded along the bottom corner diagonal crease line 14. After folding, the overlapping areas of adjacent second side covering areas 23 will overlap, and the two side covering overlapping areas 242 adjacent to the second side covering area 23 will also have partial overlap. After the entire bottom corner covering area 24 is folded, the bottom corner covering area 24 will wrap the two overlapping side covering overlapping areas 242, and the remaining two side covering overlapping areas 242 will wrap the overlapping areas of the two overlapping second side covering areas 23.

[0086] It needs to be explained that the insulating film 1 is in an unfolded state when not in use, and the unfolded state of the insulating film 1 is rectangular; the insulating film 1 will be folded along the bottom crease line 11, the side crease line 12, the top crease line 13 and the bottom corner oblique crease line 14 when in use, so that the insulating film 1 forms a use state for wrapping the shell 2. In order to make the utility model more convenient to understand, the utility model embodiment provides a high-yield lithium ion battery insulating film 1 automatic film wrapping process, as shown in Figures 3 to 5 The specific process flow is as follows:

[0087] Step 1: First, the bottom covering area 21 wraps the bottom surface of the shell 2;

[0088] Step 2: Fold the first side covering area 22 along the bottom crease line 11, so that the first side covering area 22 wraps the first side of the shell 2;

[0089] Step 3: Cut the bottom corner covering area 24 (three-word cutting), to form a stress release opening 15 and two cutouts 16;

[0090] Step 4: Fold the second side covering area 23 along the side crease line 12 and the bottom corner oblique crease line 14, so that the second side covering area 23 wraps the second side of the shell 2;

[0091] Step 5: Block the bottom corner covering area 24 along the side crease line 12, so that the bottom corner covering area 24 wraps the second side covering area 23;

[0092] Step 6: Fold the top first covering area 251 along the top crease line 13, and fold the top second covering area 252 along the second side crease line 12, so that the top first covering area 251 and the top second covering area 252 wrap the edges of the top of the shell 2;

[0093] Step 7: Perform top hot pressing; steps 6 and 7 can be omitted, which is determined by the structure of the insulating film 1;

[0094] Step 8: Paste the insulating sheet.

[0095] As shown in Figure 6 After the film wrapping process is completed, the two layers of side covering overlap areas 242 (two side covering overlap areas 242 adjacent to the second side covering area 23 in Figure 2 ) and the one layer of bottom corner covering overlap area 241 overlap the two layers of second side covering areas 23 to form a five-layer overlap area 31, and the one layer of side covering overlap area 242 (one side covering overlap area 242 adjacent to the second side covering area 23 in Figure 2 ) and the one layer of bottom corner covering overlap area 241 overlap the one layer of second side covering area 23 to form a first three-layer overlap area 32; at the same time, the one layer of side covering overlap area 242 (one side covering overlap area 242 adjacent to the second side covering area 23 in Figure 2The two layers of the second side covering area 23 and one of the side covering overlap areas 242 which is not adjacent to the second side covering area 23 form a second three-layer overlap area 41. The two layers of the second side covering area 23 and the non-overlap area of one of the side covering overlap areas 242 form a two-layer overlap area 42. Figure 2 The two layers of the second side covering area 23 and one of the side covering overlap areas 242 which is not adjacent to the second side covering area 23 form a second three-layer overlap area 41. The two layers of the second side covering area 23 and the non-overlap area of one of the side covering overlap areas 242 form a two-layer overlap area 42.

[0096] The length of the bottom covering area 21 and the width of the bottom covering area 21 are not limited in the embodiment and can be determined according to the length of the bottom surface and the width of the bottom surface of the shell 2. The length of the first side covering area 22 and the width of the first side covering area 22 are not limited in the embodiment and can be determined according to the length of the first side surface and the width of the first side surface of the shell 2. The length of the second side covering area 23 and the width of the second side covering area 23 are not limited in the embodiment and can be determined according to the length of the second side surface and the width of the second side surface of the shell 2. The relative size of the size of the first side covering area 22 and the size of the second side covering area 23 is not limited in the embodiment. The size of the first side covering area 22 can be greater than the size of the second side covering area 23. The size of the first side covering area 22 can also be smaller than the size of the second side covering area 23.

[0097] It should be noted that, as shown in Figures 7 to 9 When the size of the first side covering area 22 is greater than the size of the second side covering area 23, the length of the bottom surface and the width of the first side surface of the shell 2 are equal to the width M of the shell 2. The width of the bottom surface and the width of the second side surface of the shell 2 are equal to the thickness T of the shell 2. The length of the first side surface and the length of the second side surface of the shell 2 are equal to the height H of the shell 2.

[0098] It should be noted that, as shown in Figure 10As shown, in the unfolded state of the insulating film 1 in this embodiment, the distance L1 from the one end of the cutout 16 close to the second side covering area 23 to the bottom corner covering area 24 is equivalent to the distance L1 from the cutout 16 to the side edge of the shell 2 in the use state of the insulating film 1; the distance L2 from the stress release port 15 to the one end of the bottom corner covering area 24 close to the second side covering area 23 in the unfolded state of the insulating film 1 is equivalent to the distance L2 from the stress release port 15 to the side edge of the shell 2 in the use state of the insulating film 1; and the width L of the non-overlapping area in the unfolded state of the insulating film 1 is equivalent to the distance L from the overlapping area to the side edge of the shell 2 in the use state of the insulating film 1. In this embodiment, the distance from the overlapping area to the side edge of the shell 2 is greater than 0 and less than 2 times the thickness T of the shell 2.

[0099] It should be noted that, as shown, in the unfolded state of the insulating film 1 in this embodiment, the distance W1 from the one end of the stress release port 15 close to the bottom corner covering area 24 to the bottom corner covering area 24 is equivalent to the distance W1 from the one end of the stress release port 15 close to the bottom corner covering area 24 to the bottom side edge of the shell 2 in the use state of the insulating film 1; the distance W2 from the one end of the cutout 16 close to the bottom corner covering area 24 to the bottom corner covering area 24 in the unfolded state of the insulating film 1 is equivalent to the distance W2 from the one end of the cutout 16 close to the bottom corner covering area 24 to the bottom side edge of the shell 2 in the use state of the insulating film 1; and the length W of the cutout 16 in the unfolded state of the insulating film 1 is equivalent to the length W of the area in the bottom corner covering area 24 that is not covered by the side covering overlapping area 242 in the use state of the insulating film 1. Figure 11

[0100] This embodiment can satisfy the first relationship:

[0101] ;

[0102] In the formula, W represents the length of the cutout 16, T represents the thickness of the shell 2, and L represents the width of the non-overlapping area. It should be noted that, in this embodiment, the length W of the cutout 16 satisfies the above range, which can ensure that the bottom corner cutting is effective and prevent the shell 2 from leaking out at the bottom corner.

[0103] This embodiment can satisfy the second relationship:

[0104] ;

[0105] In the formula, W1 represents the distance from the one end of the stress release port 15 close to the bottom corner covering area 24 to the bottom corner covering area 24, and W represents the length of the cutout 16. It should be noted that, in this embodiment, the distance W1 from the one end of the stress release port 15 close to the bottom corner covering area 24 to the bottom corner covering area 24 satisfies the above range, which can ensure that the bottom corner covering area 24 has good adhesion and prevent the bottom corner covering area 24 from being warped.​​

[0106] The embodiment can satisfy the third relationship:

[0107] ;

[0108] In the formula, W2 represents the distance from the end of the cutout 16 close to the bottom surface covering area 21 to the bottom surface covering area 21, and W represents the length of the cutout 16. It should be noted that the distance W2 from the end of the cutout 16 close to the bottom surface covering area 21 to the bottom surface covering area 21 in the embodiment satisfies the above range, which can ensure the bonding effect of the bottom corner covering area 24 and prevent the bottom corner covering area 24 from being raised.

[0109] The embodiment can satisfy the fourth relationship:

[0110] ;

[0111] In the formula, W1 represents the distance from the end of the stress release port 15 close to the bottom surface covering area 21 to the bottom surface covering area 21, and W2 represents the distance from the end of the cutout 16 close to the bottom surface covering area 21 to the bottom surface covering area 21. In addition, the following can also be satisfied: It should be noted that the former has a simpler preparation process.

[0112] The embodiment can satisfy the fifth relationship:

[0113] ;

[0114] In the formula, L1 represents the distance from the cutout 16 to the side of the bottom corner covering area 24 close to the second side surface covering area 23, and L represents the width of the non-overlapping area. In addition, the following can also be satisfied: It should be noted that the distance L1 from the cutout 16 to the side of the bottom corner covering area 24 close to the second side surface covering area 23 affects the width of the two side surface covering overlapping areas 242 that are not adjacent to the second side surface covering area 23, and satisfying the above range can improve the bonding effect of the two side surface covering overlapping areas 242 that are not adjacent to the second side surface covering area 23. The embodiment can satisfy the sixth relationship:

[0115] ;

[0116] In the formula, L1 represents the distance from the cutout 16 to the side of the bottom corner covering area 24 close to the second side surface covering area 23. It should be noted that the distance L1 from the cutout 16 to the side of the bottom corner covering area 24 close to the second side surface covering area 23 in the embodiment satisfies the above range, which can prevent interference between the cutting position and the shell 2 and tearing of the bottom corner covering area 24.

[0117] The embodiment does not limit the specific range of the thickness of the insulating film 1, for example, the thickness of the insulating film 1 can be 20 μm to 200 μm.

[0118] The embodiment is not limited to the specific type of the insulating film 1, for example, the insulating film 1 can be a polyimide film, a polyolefin film or a polyamide film; or an insulating film 1 made of other materials. It should be noted that polyimide, polyolefin and polyamide are all common materials in the prior art, and the embodiment is not limited to the internal components of the insulating film 1, but directly uses a film layer made of existing materials as the insulating film 1.

[0119] Based on the above embodiment, the stress release port is arranged on the bottom corner wrapping area of the insulating film, and the stress release port is arranged in the range where the two adjacent second side wrapping areas are folded to the two overlapping areas, so that the bubbles generated by extrusion are effectively discharged from the stress release port during the process of pressing the roller to adhere the insulating film, thereby reducing the probability of side bottom corner wrinkles and bubbles, and improving the film wrapping yield.

[0120] The battery provided by the utility model is described in detail above, and for the general skilled person in the art, the specific implementation and application range will be changed according to the idea of the embodiment of the utility model, and the content of the specification should not be understood as a limitation of the utility model.

Claims

1. A battery, characterized in that, include: Insulating film (1) and housing (2); the housing (2) includes a bottom surface, two oppositely arranged first side surfaces, two oppositely arranged second side surfaces and a top surface; the insulating film (1) includes a bottom covering area (21), two first side covering areas (22), four second side covering areas (23) and two bottom corner covering areas (24). The bottom covering area (21) covers the bottom surface; The first side covering area (22) covers the first side; The second side covering area (23) covers the second side; the second side covering area (23) includes a non-overlapping area and an overlapping area, and the overlapping areas of adjacent second side covering areas (23) overlap on the second side; The bottom corner covering area (24) covers the second side covering area (23); the bottom corner covering area (24) includes a stress relief port (15), which is located in the overlapping area.

2. The battery according to claim 1, characterized in that, The overlapping area and the non-overlapping area extend along a first direction and are arranged sequentially along a second direction; The stress relief port (15) extends along the first direction from the side of the bottom corner covering area (24) away from the bottom covering area (21) toward the bottom covering area (21).

3. The battery according to claim 1, characterized in that, The bottom corner covering area (24) also includes two bottom corner diagonal crease lines (14) and two cuts (16). The cut (16) extends along the first direction from the side of the bottom corner covering area (24) away from the bottom covering area (21) toward the bottom covering area (21), and is respectively provided on both sides of the stress relief port (15) along the second direction; The bottom corner diagonal crease line (14) extends from the vertex where the bottom corner covering area (24) and the bottom covering area (21) connect to the end of the adjacent cut (16) near the bottom covering area (21); The bottom corner covering area (24) is divided into a bottom corner covering overlapping area (241) and four side covering overlapping areas (242) by the stress relief port (15), the cut (16) and the bottom corner oblique crease line (14). The two side-covering overlapping areas (242) adjacent to the second side-covering area (23) both extend along the second direction and wrap around the second side-covering area (23), and some areas overlap. The bottom corner overlapping area (241) covers the two side overlapping areas (242) adjacent to the second side covering area (23). The two side-covering overlap areas (242) that are not adjacent to the second side-covering area (23) both extend along the first direction and wrap around the second side-covering area (23).

4. The battery according to claim 3, characterized in that, Satisfies the first relation: ； In the formula, W represents the length of the cut (16), T represents the thickness of the shell (2), and L represents the width of the non-overlapping area.

5. The battery according to claim 3, characterized in that, Satisfying the second relation: ； In the formula, W1 represents the distance from the end of the stress relief port (15) near the bottom covering area (21) to the bottom covering area (21), and W represents the length of the cut (16).

6. The battery according to claim 3, characterized in that, Satisfying the third relation: ； In the formula, W2 represents the distance from the end of the cut (16) near the bottom covering area (21) to the bottom covering area (21), and W represents the length of the cut (16).

7. The battery according to claim 3, characterized in that, Satisfying the fourth relation: ； In the formula, W1 represents the distance from the end of the stress relief port (15) near the bottom covering area (21) to the bottom covering area (21), and W2 represents the distance from the end of the cut (16) near the bottom covering area (21) to the bottom covering area (21).

8. The battery according to claim 3, characterized in that, Satisfying the fifth relation: ； In the formula, L1 represents the distance from the cut (16) to the side of the bottom corner covering area (24) near the second side covering area (23), and L represents the width of the non-overlapping area.

9. The battery according to claim 3, characterized in that, Satisfying the sixth relation: ； In the formula, L1 represents the distance from the cut (16) to the side of the bottom corner covering area (24) near the second side covering area (23).

10. The battery according to claim 1, characterized in that, The insulating film (1) also includes two top surface first covering areas (251) and four top surface second covering areas (252). The top surface first covering area (251) covers the edge of the top surface near the first side surface; the top surface first covering area (251) is connected to the side of the first side covering area (22) away from the bottom covering area (21); The second covering area (252) of the top surface covers the edge of the top surface near the second side surface; the second covering area (252) of the top surface is connected to the first covering area (251) of the top surface and the second side covering area (23).

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