A battery

Abstract

The embodiment of the present application provides a battery, including a shell, an explosion-proof valve, and a battery cell located in the shell, the shell including two relatively large faces, a first large face and a second large face, each of the first large face and the second large face including two relatively long sides and two relatively short sides, four small faces are arranged between the first large face and the second large face, two relatively first side faces and two relatively second side faces, the first side face is connected to the short side, the second side face is connected to the long side, the connection between the first large face and the first side face is recessed toward the second large face to form a concave portion, the lead-out end of the pole ear is arranged opposite to the concave portion, the concave portion and the first side face and part of the second large face form a convex portion, the pole ear is at least partially accommodated in the convex portion, a transition surface is formed between the second side face and the concave portion, the explosion-proof valve is arranged on the second side face, and the maximum distance between the explosion-proof valve and the transition surface is in the range of 0.1mm-10mm. The explosion position of the battery is more concentrated when thermal runaway occurs, which is more conducive to directional exhaust.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery. Background Art

[0002] Some batteries with irregularly shaped casings may explode at a point other than the explosion-proof valve during thermal runaway, preventing directional venting. Therefore, ensuring that batteries with irregularly shaped casings can explode at the explosion-proof valve location for directional venting during thermal runaway poses a technical challenge for those skilled in the art. Summary of the Invention

[0003] In order to solve the above technical problems, the present application provides a battery, the battery comprising a shell, an explosion-proof valve, and a battery cell located in the shell, the battery cell comprising a battery cell body and a tab, the tab being led out from opposite ends of the battery cell body, the shell comprising two relatively large surfaces, namely a first large surface and a second large surface, the first large surface and the second large surface each comprising two relatively long sides and two relatively short sides, four small surfaces being arranged between the first large surface and the second large surface, namely two relatively first side surfaces and two relatively second side surfaces, the first side surface being connected to the short side The second side surface is connected to the long side, and the connection between the first large surface and the first side surface is recessed toward the second large surface to form a recess, and the recess passes through the entire first large surface along the extension direction of the short side. The tab lead-out end of the battery cell body is arranged opposite to the recess, and the recess forms a convex portion with the first side surface and part of the second large surface. The tab is at least partially accommodated in the convex portion, and a transition surface is formed between the second side surface and the recess. The explosion-proof valve is provided on the second side surface, and the maximum distance between the explosion-proof valve and the transition surface is a, 0.1mm≤a≤10mm.

[0004] In the battery provided herein, the explosion-proof valve is positioned near the transition surface of the housing. This transition surface represents a weak area of ​​the housing. In the event of thermal runaway, the explosion is concentrated near the explosion-proof valve and the transition surface, achieving directional venting. Because the recessed portion is recessed toward the second major surface, the transition surface between the recessed portion and the second side surface represents a weak area of ​​the housing. To position the explosion-proof valve close to the weak transition surface, the valve can be positioned within the recessed portion or the second side surface. Since the tab leads of the battery cell body are positioned relative to the recessed portion, the tabs are at least partially accommodated within the raised portion formed by the recessed portion, the first side surface, and the second major surface. Therefore, if the tabs deform (they are thin and easily deformed), they are likely to interfere with the recessed portion. Therefore, if the explosion-proof valve is positioned within the recessed portion, the tabs are likely to interfere with the valve, preventing it from detonating. Therefore, the present application arranges the explosion-proof valve on the second side surface, and controls the maximum distance between the explosion-proof valve and the transition surface to be less than or equal to 10 mm, so that the explosion-proof valve is close to the transition surface, and controls the maximum distance between the explosion-proof valve and the transition surface to be greater than or equal to 0.1 mm, so that there is a certain distance between the explosion-proof valve and the transition surface, and the explosion-proof valve is not on the transition surface. If the explosion-proof valve is on the transition surface, the strength of the transition surface will be further weakened, causing the shell to be easily deformed, affecting the normal use of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 A perspective view of an embodiment of a battery provided by the present application, wherein components within the housing are indicated by dotted lines;

[0006] Figure 2 for Figure 1 A three-dimensional view of the middle battery cell and the second largest surface;

[0007] Figure 3 for Figure 1 Bottom view of

[0008] Figure 4 for Figure 1 A top view of

[0009] Figure 5 for Figure 1 A partial enlarged view of

[0010] Figure 6 for Figure 5 Side view of

[0011] Figure 7 for Figure 5 A top sectional view of

[0012] Figure 8 for Figure 5 Side sectional view of .

[0013] The following are the descriptions of the reference numerals:

[0014] 1 housing, 11 first large surface, 12 second large surface, 13 first side surface, 14 second side surface, 15 recess, 16 liquid injection hole, 17 plane, 18 curved surface, 19 transition surface;

[0015] 2 battery cells, 21 battery cell bodies, 22 tabs;

[0016] 3. Insulation support frame;

[0017] 4 poles;

[0018] 5. Explosion-proof valve. DETAILED DESCRIPTION

[0019] The present application provides a battery. In order to enable those skilled in the art to better understand the technical solution of the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0020] like Figure 1 and Figure 2 As shown, the battery provided in this application includes a shell 1, a battery cell 2 and an explosion-proof valve 5.

[0021] The housing 1 includes two opposing large surfaces, namely a first large surface 11 and a second large surface 12. Each of the first and second large surfaces 11 and 12 includes two opposing long sides and two opposing short sides. Four small surfaces are disposed between the first and second large surfaces 11 and 12, namely two opposing first side surfaces 13 and two opposing second side surfaces 14. The first side surfaces 13 are connected to the short sides, and the second side surfaces 14 are connected to the long sides.

[0022] The junction between the first large surface 11 and the first side surface 13 is recessed toward the second large surface 12 to form a recess 15. The recess 15 extends through the entire first large surface 11 along the direction of the short side. The recess 15 is used to accommodate an insulating member when the batteries are assembled.

[0023] The recess 15 forms a raised portion with the first side surface 13 and part of the second large surface 12. In the illustrated embodiment, a pole 4 is provided on the second large surface 12, and the tab 22 is electrically connected to the pole 4. In the illustrated embodiment, the recess 15 has a flat surface 17 and an arc surface 18. The flat surface 17 is connected to the first side surface 13. One side of the arc surface 18 is connected to the flat surface 17 and the other side is connected to the first large surface 11. The flat surface 17 is parallel to the first large surface 11 or has a very small angle with the first large surface 11. The flat surface 17 forms a first branch of the raised portion with the first side surface 13 and part of the second side surface 14. The arc surface 18 forms a second branch of the raised portion with part of the second side surface 14. The height of the first branch in the direction in which the first large surface 11 and the second large surface 12 are arranged is less than the height of the second branch in the direction in which the first large surface 11 and the second large surface 12 are arranged.

[0024] The battery cell 2 is located in the shell 1. The battery cell 2 includes a battery cell body 21 and a tab 22. The tab 22 is led out from the opposite ends of the battery cell body 21. Specifically, the battery cell body 21 includes a positive electrode sheet and a negative electrode sheet. The positive electrode sheets and the negative electrode sheets are arranged alternately one by one, and a separator is provided between adjacent positive electrode sheets and negative electrode sheets. The structures of the positive electrode sheets and the negative electrode sheets are similar, both including a conductive layer and an active material layer coated on the conductive layer. The portion of the conductive layer of the positive electrode sheet that is not coated with the active material protrudes from the portion that is coated with the active material to form a positive electrode tab single piece, and multiple layers of positive electrode tab single pieces are stacked to form a positive electrode tab. The portion of the conductive layer of the negative electrode sheet that is not coated with the active material protrudes from the portion that is coated with the active material to form a negative electrode tab single piece, and multiple layers of negative electrode tab single pieces are stacked to form a negative electrode tab.

[0025] The tab lead end of the cell body 21 is disposed opposite the recess 15, and the tab 22 is at least partially accommodated in the raised portion of the housing 1. In the illustrated embodiment, a portion of the tab 22 is accommodated in the first subsection of the raised portion, and a portion of the tab 22 is accommodated in the second subsection of the raised portion.

[0026] A transition surface 19 is formed between the second side surface 14 and the recess 15. The explosion-proof valve 5 is provided on the second side surface 14. The maximum distance between the explosion-proof valve 5 and the transition surface 19 is a, 0.1mm≤a≤10mm. For example, a can be equal to 0.1mm, 0.2mm, 0.4mm, 1mm, 2mm, 4mm, 6mm, 8mm, 10mm. Specifically, the explosion-proof valve 5 can be an integral structure with the shell 1. For example, a thinning area can be formed by stamping the shell 1, and the thinning area is used as the explosion-proof valve 5, or a notch can be provided on the shell 1, and the notch is used as the explosion-proof valve 5. The explosion-proof valve 5 can also be a non-integrated structure with the shell 1. For example, an explosion-proof opening can be provided on the shell 1, and the explosion-proof valve 5 can be a patch attached to the explosion-proof opening.

[0027] In the above-described battery, the explosion-proof valve 5 is positioned near the transition surface 19 of the casing 1. This transition surface 19 represents a weak area of ​​the casing 1. In the event of thermal runaway, the explosion location is concentrated near the explosion-proof valve 5 and the transition surface 19, achieving directional venting. Because the recess 15 is recessed toward the second major surface 12, the transition surface 19 between the recess 15 and the second side surface 14 represents a weak area of ​​the casing 1. To position the explosion-proof valve 5 close to the weak transition surface 19, the valve 5 can be positioned in the recess 15 or the second side surface 14. Since the tab lead-out terminal of the cell body 21 is positioned opposite the recess 15, the tab 22 is at least partially accommodated within the raised portion formed by the recess 15, the first side surface 13, and the second major surface 12. Therefore, if the tab 22 deforms (the tab 22 is thin and easily deformed), it is likely to interfere with the recess 15. Therefore, if the explosion-proof valve 5 is positioned in the recess 15, the tab 22 will likely interfere with the valve 5, preventing it from opening. Therefore, the present application arranges the explosion-proof valve 5 on the second side surface 14, and controls the maximum distance between the explosion-proof valve 5 and the transition surface 19 to be less than or equal to 10 mm, so that the explosion-proof valve 5 is close to the transition surface 19, and controls the maximum distance between the explosion-proof valve 5 and the transition surface 19 to be greater than or equal to 0.1 mm, so that there is a certain distance between the explosion-proof valve 5 and the transition surface 19, and the explosion-proof valve 5 is not on the transition surface 19. If the explosion-proof valve 5 is on the transition surface 19, the strength of the transition surface 19 will be further weakened, causing the shell 1 to be easily deformed, affecting the normal use of the battery.

[0028] In some embodiments, such as Figure 8 As shown, the battery includes an insulating support frame 3. The insulating support frame 3 is at least partially located in the raised portion. The insulating support frame 3 is used to fix the converged tab 22. At least part of the insulating support frame 3 is located between the recess 15 and the tab 22. When the insulating support frame 3 is set, 0.1mm≤a≤7mm. The insulating support frame 3 causes the force of the thermal runaway airflow to impact the explosion-proof valve 5 to be reduced, which is not conducive to the explosion-proof valve 5 to explode. Therefore, in order to make the explosion-proof valve 5 easy to explode, it is necessary to make the explosion-proof valve 5 closer to the weak transition surface 19. Therefore, the value of a can be slightly smaller. Therefore, this embodiment controls the upper limit value of a to be reduced to 7mm.

[0029] In some embodiments, the length of the explosion-proof valve 5 accounts for 50%-70% of the length of the recess 15. For example, the length can be 50%, 55%, 60%, 65%, or 70%. The length of the explosion-proof valve 5 refers to the length from the end of the explosion-proof valve 5 closest to the first large surface 11 to the end of the explosion-proof valve 5 closest to the first side surface 13. The length of the explosion-proof valve 5 ranges from 10 mm to 30 mm. For example, the length can be 10 mm, 15 mm, 20 mm, 20.4 mm, 25 mm, or 30 mm. The length of the recess 15 refers to the length from the end of the recess 15 connected to the first large surface 11 to the end of the recess 15 connected to the first side surface 13. Specifically, the length of the recess 15 ranges from 20 mm to 40 mm. For example, the length can be 20 mm, 25 mm, 30 mm, 31 mm, 35 mm, or 40 mm. When the length of the explosion-proof valve 5 accounts for 50%-70% of the length of the recess 15, 0.2 mm ≤ a ≤ 8 mm.

[0030] When the length of the recess 15 is constant, the greater the ratio of the length of the explosion-proof valve 5 to the length of the recess 15, the greater the length of the explosion-proof valve 5, and the easier it is to burst. In this case, the value of a can be slightly larger to prevent the explosion-proof valve 5 from bursting before reaching the specified pressure. Conversely, when the length of the recess 15 is constant, the smaller the ratio of the length of the explosion-proof valve 5 to the length of the recess 15, the smaller the length of the explosion-proof valve 5, and the harder it is to burst. In this case, the value of a can be slightly smaller to facilitate the bursting of the explosion-proof valve 5. Therefore, the range of a can be adjusted by controlling the ratio of the length of the explosion-proof valve 5 to the length of the recess 15, so that the range of a facilitates the formation of the explosion-proof valve 5 during the manufacturing process. In this embodiment, by controlling the ratio of the length of the explosion-proof valve 5 to the length of the recess 15 to be 50%-70%, the range of a is adjusted to 0.2 mm-8 mm. When a is 0.2 mm-8 mm, it facilitates the formation of the explosion-proof valve 5 during the manufacturing process.

[0031] In some embodiments, the minimum distance between the end of the explosion-proof valve 5 close to the first side surface 13 and the first side surface 13 is b, 5mm≤b≤20mm. For example, b can be equal to 5mm, 6mm, 8mm, 9mm, 9.3mm, 10mm, 15mm, or 20mm.

[0032] If the end of the explosion-proof valve 5 closest to the first side surface 13 is too close to the first side surface 13, that is, if b is too small, the strength of the edge of the housing 1 (especially the intersection of the plane 17, the first side surface 13, and the second side surface 14) will be too low, causing the housing 1 to easily deform and break, affecting the normal use of the battery. If the end of the explosion-proof valve 5 closest to the first side surface 13 is too far from the first side surface 13, that is, if b is too large, the length of the explosion-proof valve 5 will be insufficient, which is not conducive to the explosion-proof valve 5. In this application, b is controlled to be between 5mm and 20mm. This ensures that the strength of the edge of the housing 1 meets the requirements and that the explosion-proof valve 5 can be smoothly opened.

[0033] In some embodiments, the second side surface 14 is secured to the second large surface 12 by welding, and the ratio of the minimum distance between the end of the explosion-proof valve 5 closest to the second large surface 12 and the second large surface 12 (c in the figure) to the distance between the first large surface 11 and the second large surface 12 (d in the figure) ranges from 5% to 35%, and can be, for example, 5%, 10%, 15%, 20%, 25%, 30%, or 35%. Specifically, the minimum distance between the end of the explosion-proof valve 5 closest to the second large surface 12 and the second large surface 12 ranges from 0.5 mm to 10 mm, and can be, for example, 0.5 mm, 1 mm, 2 mm, 2.5 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm. Specifically, the distance between the first large surface 11 and the second large surface 12 ranges from 15 mm to 45 mm, and can be, for example, 15 mm, 16 mm, 18.8 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, or 45 mm.

[0034] If the explosion-proof valve 5 is too close to the weld mark, the weld mark will weaken the strength of the explosion-proof valve 5, causing the explosion-proof valve 5 to deform easily, which is not conducive to the explosion of the explosion-proof valve 5. If the explosion-proof valve 5 is too far from the weld mark, the length of the explosion-proof valve 5 will be too short, which is also not conducive to the explosion of the explosion-proof valve 5. The present application controls the ratio of the minimum distance between the end of the explosion-proof valve 5 closest to the second large surface 12 and the second large surface 12 to the distance between the first large surface 11 and the second large surface 12 to 5%-35%, which can ensure that the explosion-proof valve 5 will explode smoothly when the battery experiences thermal runaway.

[0035] In some embodiments, the ratio of the minimum height of the raised portion in the direction in which the first and second large surfaces 11 and 12 are aligned (e in the figure) to the distance between the first and second large surfaces 11 and 12 (d in the figure) is in the range of 30%-55%, and can be, for example, 30%, 35%, 40%, 45%, 50%, or 55%. Specifically, the minimum height of the raised portion in the direction in which the first and second large surfaces 11 and 12 are aligned is in the range of 7mm-13.8mm, and can be, for example, 7.0mm, 7.8mm, 8.8mm, 9.8mm, 10.8mm, 11.8mm, or 13.8mm. Specifically, the distance between the first and second large surfaces 11 and 12 is in the range of 15mm-45mm, and can be, for example, 15mm, 16mm, 18.8mm, 20mm, 25mm, 30mm, 35mm, 40mm, or 45mm. When the ratio of the minimum height of the protrusion in the arrangement direction of the first large surface 11 and the second large surface 12 to the distance between the first large surface 11 and the second large surface 12 is in the range of 30%-55%, 0.1mm≤a≤6mm.

[0036] The greater the ratio of the minimum height of the raised portion in the direction of alignment of the first and second major surfaces 11, 12 to the distance between the first and second major surfaces 11, 12, the shorter the length of the recess 15, the shorter the length of the transition surface 19, and the greater the strength of the transition surface 19. The smaller the ratio of the minimum height of the raised portion in the direction of alignment of the first and second major surfaces 11, 12 to the distance between the first and second major surfaces 11, 12, the longer the length of the recess 15, the longer the length of the transition surface 19, and the weaker the strength of the transition surface 19. When the strength of the transition surface 19 is greater, the value of a can be slightly smaller to facilitate the opening of the explosion-proof valve 5. When the strength of the transition surface 19 is less, the value of a can be slightly larger to prevent the explosion-proof valve 5 from bursting before the specified pressure is reached. When the ratio of the minimum height of the raised portion in the direction of alignment of the first and second major surfaces 11, 12 to the distance between the first and second major surfaces 11, 12 is within the range of 30%-55%, controlling the value of a between 0.1 mm and 6 mm achieves optimal valve opening stability.

[0037] In some embodiments, the wall thickness of the transition surface 19 ( Figure 7 g) is less than the wall thickness of the second side surface 14 ( Figure 7 i), is also smaller than the concave portion 15 ( Figure 7 The wall thickness of explosion-proof valve 5 ( Figure 7 f) is less than or equal to the wall thickness of the transition surface 19. With this design, when a specific pressure is reached in the shell 1, the explosion-proof valve 5 and the transition surface 19 will explode, allowing the thermal runaway airflow to be quickly discharged.

[0038] In some embodiments, the wall thickness of the explosion-proof valve 5 ( Figure 7 f) accounts for the wall thickness of the second side 14 ( Figure 7The ratio in (i) is in the range of 35%-68%, and can be, for example, 35%, 40%, 45%, 50%, 55%, 60%, 65%, or 68%. When the ratio of the wall thickness of the explosion-proof valve 5 to the wall thickness of the second side surface 14 is in the range of 35%-68%, 0.2 mm ≤ a ≤ 5 mm.

[0039] When the wall thickness of the second side surface 14 is constant, the greater the proportion of the wall thickness of the explosion-proof valve 5 to the wall thickness of the second side surface 14, the thicker the wall thickness of the explosion-proof valve 5 is. In this case, the value of a can be slightly smaller to facilitate the explosion-proof valve 5's opening. Conversely, when the wall thickness of the second side surface 14 is constant, the smaller the proportion of the wall thickness of the explosion-proof valve 5 to the wall thickness of the second side surface 14, the thinner the wall thickness of the explosion-proof valve 5 is. In this case, the value of a can be slightly larger to avoid being too close to the transition surface 19, which may cause the explosion-proof valve 5 to burst before the specified pressure is reached. When the proportion of the wall thickness of the explosion-proof valve 5 to the wall thickness of the second side surface 14 is within the range of 35%-68%, controlling the value of a within 0.2mm-5mm achieves optimal valve opening stability.

[0040] In some embodiments, a concave portion 15 is formed at the connection between the first large surface 11 and the two first side surfaces 13, and the battery includes two explosion-proof valves 5, such as Figure 4 As shown, Figure 4 An explosion-proof valve 5 is provided at each of the two circled locations. One explosion-proof valve 5 is located on one second side surface 14, close to a transition surface 19 connected to one recess 15. The other explosion-proof valve 5 is located on the other second side surface 14, close to a transition surface 19 connected to the other recess 15, so that the two explosion-proof valves 5 are arranged diagonally. This design avoids the problem of two explosion-proof valves 5 being located on the same second side surface 14, where the opening of one explosion-proof valve 5 would cause the other explosion-proof valve 5 to deform and thus prevent it from opening.

[0041] In the illustrated embodiment, Figure 5 As shown, the explosion-proof valve 5 is an arc-shaped explosion-proof valve 5 extending along the transition surface 19. Specifically, the width of the arc-shaped explosion-proof valve 5 is j, 0.05mm≤j≤0.5mm. For example, j can be equal to 0.1mm, 0.2mm, 0.3mm, 0.4mm, or 0.5mm. Excessively wide or too narrow a width will not facilitate the opening of the explosion-proof valve 5. In other embodiments, the explosion-proof valve 5 can also have other shapes, such as straight, triangular, circular, rectangular, cross-shaped, T-shaped, or X-shaped.

[0042] In the illustrated embodiment, Figure 6As shown, the distance between the two ends of the arc-shaped explosion-proof valve 5 (the end closest to the first large surface 11 and the end closest to the second large surface 12) in the arrangement direction of the first large surface 11 and the second large surface 12 (k in the figure) accounts for 60%-100% of the distance between the first large surface 11 and the second large surface 12 (d in the figure). For example, it can be equal to 60%, 70%, 80%, 90%, or 100%. When the distance between the two ends of the arc-shaped explosion-proof valve 5 in the arrangement direction of the first large surface 11 and the second large surface 12 accounts for 60%-100% of the distance between the first large surface 11 and the second large surface 12, 0.2mm≤a≤8mm.

[0043] When the extension direction of the arc-shaped explosion-proof valve 5 is constant, the greater the ratio of the distance between the two ends of the arc-shaped explosion-proof valve 5 in the arrangement direction of the first large surface 11 and the second large surface 12 to the distance between the first large surface 11 and the second large surface 12, the longer the length of the arc-shaped explosion-proof valve 5 is, and the easier it is for the arc-shaped explosion-proof valve 5 to burst. In this case, the value of a can be slightly larger to prevent the explosion-proof valve 5 from bursting when the specific pressure is not reached. Conversely, when the extension direction of the arc-shaped explosion-proof valve 5 is constant, the smaller the ratio of the distance between the two ends of the arc-shaped explosion-proof valve 5 in the arrangement direction of the first large surface 11 and the second large surface 12 to the distance between the first large surface 11 and the second large surface 12 is, the smaller the length of the arc-shaped explosion-proof valve 5 is, and the more difficult it is for the arc-shaped explosion-proof valve 5 to burst. In this case, the value of a can be slightly smaller to facilitate the bursting of the explosion-proof valve 5. Therefore, the range of a can be adjusted by controlling the ratio of the distance between the two ends of the arc-shaped explosion-proof valve 5 in the arrangement direction of the first large surface 11 and the second large surface 12 to the distance between the first large surface 11 and the second large surface 12, so that the range of a is convenient for the formation of the explosion-proof valve 5 in the process manufacturing. In this embodiment, by controlling the ratio of the distance between the two ends of the arc-shaped explosion-proof valve 5 in the arrangement direction of the first large surface 11 and the second large surface 12 to the distance between the first large surface 11 and the second large surface 12 to be 60%-100%, the range of a is adjusted to 0.2mm-8mm, and when a is 0.2mm-8mm, it is convenient for the formation of the explosion-proof valve 5 in the process manufacturing.

[0044] The housing 1 is provided with a liquid injection hole 16. In the illustrated embodiment, the liquid injection hole 16 is provided on the second large surface 12. The center line of the second large surface 12 parallel to the long side is the first center line ( Figure 3 L1), the center line parallel to the short side is the second center line ( Figure 3 In the diagram (L2), the injection hole 16 is located on one side of the first centerline and on one side of the second centerline. The injection hole 16 and the explosion-proof valve 5 on the same side of the second centerline are located on either side of the first centerline. This design prevents deformation of the explosion-proof valve 5 caused by pressure on the housing 1 during the process of opening the injection hole 16B and the injection process, which could prevent the explosion-proof valve 5 from opening smoothly when the battery experiences thermal runaway.

[0045] The principles and implementation methods of the present application have been described above using specific examples. The description of the above embodiments is only intended to help understand the method and core concept of the present application. It should be noted that for those skilled in the art, without departing from the principles of the present application, various improvements and modifications may be made to the present application, and such improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A battery, characterized in that: The battery comprises a shell, an explosion-proof valve, and a cell in the shell, wherein the cell comprises a cell body and a tab, wherein the tab is led out from opposite ends of the cell body, the shell comprises two relatively large surfaces, namely a first large surface and a second large surface, wherein the first large surface and the second large surface each comprise two relatively long sides and two relatively short sides, wherein four small surfaces are arranged between the first large surface and the second large surface, namely two relatively first side surfaces and two relatively second side surfaces, wherein the first side surface is connected to the short side, the second side surface is connected to the long side, and the first large surface is connected to the The connection point of the first side surface is recessed toward the second large surface to form a recess, and the recess passes through the entire first large surface along the extension direction of the short side. The lead-out end of the battery cell body is arranged opposite to the recess, and the recess, the first side surface and part of the second large surface form a protrusion, and the pole ear is at least partially accommodated in the protrusion. A transition surface is formed between the second side surface and the recess, and the transition surface is a weak area of ​​the shell. The explosion-proof valve is arranged on the second side surface, and the explosion-proof valve is arranged close to the transition surface. The maximum distance between the explosion-proof valve and the transition surface is a, 0.1mm≤a≤10mm.

2. The battery according to claim 1, characterized in that The battery comprises an insulating support frame, wherein at least a part of the insulating support frame is located in the protruding portion, and the insulating support frame is used to fix and gather the pole lug, and at least a part of the insulating support frame is located between the recess and the pole lug, and 0.1 mm≤a≤7 mm.

3. The battery according to claim 1, characterized in that The ratio of the length of the explosion-proof valve to the length of the recess is in the range of 50%-70%, and 0.2mm≤a≤8mm.

4. The battery according to claim 1, characterized in that The minimum distance between the end of the explosion-proof valve close to the first side surface and the first side surface is b, and 5mm≤b≤20mm.

5. The battery according to claim 1, characterized in that The second side surface is fixed to the second large surface by welding, and the ratio of the minimum distance between the end of the explosion-proof valve close to the second large surface and the second large surface to the distance between the first large surface and the second large surface is in the range of 5%-35%.

6. The battery according to claim 1, characterized in that The ratio of the minimum height of the protrusion in the arrangement direction of the first large surface and the second large surface to the distance between the first large surface and the second large surface is in the range of 30%-55%, and 0.1mm≤a≤6mm.

7. The battery according to claim 1, characterized in that The wall thickness of the transition surface is smaller than the wall thickness of the second side surface and also smaller than the wall thickness of the recessed portion. The wall thickness of the explosion-proof valve is smaller than or equal to the wall thickness of the transition surface.

8. The battery according to claim 1, characterized in that The ratio of the wall thickness of the explosion-proof valve to the wall thickness of the second side surface is in the range of 35%-68%, and 0.2mm≤a≤5mm.

9. The battery according to claim 1, characterized in that A recess is formed at each connection between the first large surface and the two first side surfaces, and the battery comprises two explosion-proof valves, one explosion-proof valve is arranged on one of the second side surfaces and close to the transition surface connected to one of the recesses, and the other explosion-proof valve is arranged on the other of the second side surfaces and close to the transition surface connected to the other of the recesses.

10. The battery according to claim 1, characterized in that The explosion-proof valve is an arc-shaped explosion-proof valve extending along the transition surface.

11. The battery according to claim 10, characterized in that The distance between the two ends of the arc-shaped explosion-proof valve in the arrangement direction of the first large surface and the second large surface accounts for 60%-100% of the distance between the first large surface and the second large surface, and 0.2mm≤a≤8mm.

12. The battery according to any one of claims 1 to 11, characterized in that: The shell is provided with an injection hole, and the injection hole is provided on the second large surface. The center line of the second large surface parallel to the long side is the first center line, and the center line parallel to the short side is the second center line. The injection hole is located on one side of the first center line and on one side of the second center line. The injection hole and the explosion-proof valve located on the same side of the second center line are respectively located on both sides of the first center line.

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