Battery and electric device

Abstract

The invention relates to the technical field of batteries, and discloses a battery and a power utilization device, and the battery comprises a battery cell which comprises a battery cell body and a tab part; a first surface is formed on one surface, far away from the battery cell body, of the switching piece, at least part of the tab part is folded to the first surface from the first edge of the switching piece and is welded with the first surface to form a first welding area, and the end part of the tab part completely exceeds the first welding area in the x direction; the pole column is welded on the first surface and forms a second welding area; and along the x direction, the minimum distance between the edge of the first welding area and the outer wall of the pole is d, the maximum distance between the end part of the tab part and the first edge is b, the minimum distance between the end part of the tab part and the first edge is a, and d-(b-a) is more than or equal to-10mm and less than or equal to 30mm. According to the invention, while the welding quality of the pole and the adapter plate and the overcurrent capability between the pole and the adapter plate are ensured, the thermal runaway risk of the battery is reduced, and the safety performance of the battery is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to batteries and electrical devices. Background Art

[0002] Batteries are typically electrically connected to cells via poles, which also enable charging and discharging. Specifically, the tabs of a cell are electrically connected to the poles via adapters. When welding the tabs to the adapters, the tabs are typically welded to the bottom surface of the adapters, requiring a large amount of space between the adapters and the cell. This results in low battery space utilization and affects the battery's energy density.

[0003] In order to further improve the space utilization in the height direction of the battery, the tabs can be welded to the upper surface of the adapter. However, the above arrangement causes the tabs to affect the overall assembly of the pole assembly and affect the welding yield of the pole assembly. Summary of the Invention

[0004] In view of this, the present invention provides a battery and an electrical device to solve the problem in the prior art that the tab affects the overall assembly of the electrode assembly and affects the welding yield of the electrode assembly.

[0005] In a first aspect, the present invention provides a battery, comprising: a battery cell, comprising a battery cell body and a pole ear portion, the pole ear portion extending from at least one end of the battery cell body, and the pole ear portion being electrically connected to the battery cell body; a transition piece, spaced apart from the battery cell body along the z direction, the side of the transition piece away from the battery cell body forming a first surface, at least a portion of the pole ear portion folded from the first edge of the transition piece to the first surface, and welded to the first surface to form a first welding area, along the x direction, the end of the pole ear portion completely exceeds the first welding area; a pole post, welded to the first surface of the transition piece and forming a second welding area, the end of the pole ear portion being spaced apart from the pole post; wherein, along the x direction, the minimum distance between the edge of the first welding area and the outer wall of the pole post is d, the maximum distance between the end of the pole ear portion and the first edge is b, and the minimum distance between the end of the pole ear portion and the first edge is a, satisfying -10mm≤d-(ba)≤30mm.

[0006] Beneficial effect: While ensuring the welding quality of the pole and the adapter, as well as the overcurrent capacity between the pole and the adapter, the risk of thermal runaway of the battery is reduced, and the safety performance of the battery is guaranteed. Specifically, if d-(ba) is less than -10mm, the risk of overlap between the end of the pole ear and the pole is greater, and the end of the pole ear is easily inserted between the pole and the adapter. There is still a problem of poor welding quality between the pole and the adapter due to the occurrence of cold welding between the pole and the adapter, which in turn affects the overcurrent capacity between the pole and the adapter. In addition, it also causes the area used for welding the pole ear and the adapter to be too small, which affects the overcurrent capacity between the pole ear and the adapter. If d-(ba) is greater than 30mm, the overcurrent transmission path from the pole ear through the adapter to the pole is too long, resulting in an excessively large internal resistance of the transmission path, causing the connection between the adapter and the pole ear to generate too much heat when transmitting current, which can easily cause thermal runaway of the battery and affect the safety performance of the battery.

[0007] In a second aspect, the present invention provides an electrical device comprising the above-mentioned battery, wherein at least two batteries are provided, and poles of at least two adjacent batteries are electrically connected via a conductive bus. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0009] Figure 1 This is a schematic diagram of the overall structure of a battery according to an embodiment of the present invention;

[0010] Figure 2 for Figure 1 a top view of the battery shown;

[0011] Figure 3 for Figure 2 Cross-sectional view in the AA direction;

[0012] Figure 4 for Figure 3 A partial enlarged schematic diagram of B in the middle;

[0013] Figure 5 Schematic diagram of the structure of the pole ear when the size of e is too small;

[0014] Figure 6 Schematic diagram of the structure of the pole ear when the size of e is too large;

[0015] Figure 7Schematic diagram of the structure of the pole ear, adapter and pole in the x-direction according to an embodiment of the present invention;

[0016] Figure 8 Schematic diagram of the structure of the battery cell and adapter sheet according to an embodiment of the present invention;

[0017] Figure 9 This is a schematic structural diagram of an adapter sheet according to an embodiment of the present invention;

[0018] Figure 10 for Figure 9 A top view of the adapter shown;

[0019] Figure 11 This is a schematic structural diagram of another adapter sheet according to an embodiment of the present invention;

[0020] Figure 12 This is a schematic structural diagram of another adapter sheet according to an embodiment of the present invention;

[0021] Figure 13 for Figure 7 a partial dimensioned schematic diagram of the structure shown;

[0022] Figure 14 for Figure 7 A further dimensioned schematic diagram of a portion of the structure shown;

[0023] Figure 15 A schematic diagram of another matching structure of the pole and the first protruding structure according to an embodiment of the present invention;

[0024] Figure 16 A schematic diagram of the cooperation between the second sub-surface and the first end face according to an embodiment of the present invention;

[0025] Figure 17 Schematic diagram of another matching between the second sub-surface and the first end face according to an embodiment of the present invention.

[0026] Description of reference numerals:

[0027] 1. Battery cell; 11. Battery cell body; 12. Ear portion; 2. Adapter; 21. First surface; 211. First sub-surface; 212. Second sub-surface; 22. First edge; 23. Weak area; 24. Fuse structure; 25. Hollowing; 26. First protruding structure; 27. Sheet; 3. First welding area; 4. Pole; 41. First column segment; 42. Second column segment; 43. First end face; 5. Second welding area; 6. Lower insulator; 61. Second protruding structure; 7. Cover plate; 71. Third protruding structure; 8. Shell; 9. Outer shell. DETAILED DESCRIPTION

[0028] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, 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. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0029] The following combination Figures 1 to 17 , describing embodiments of the present invention.

[0030] According to an embodiment of the present invention, in a first aspect, a battery is provided, comprising: a battery cell 1, comprising a battery cell body 11 and a pole ear portion 12, the pole ear portion 12 extending from at least one end of the battery cell body 11, the pole ear portion 12 being electrically connected to the battery cell body 11; a transfer plate 2, spaced apart from the battery cell body 11 along the z-direction, the side of the transfer plate 2 away from the battery cell body 11 forming a first surface 21, at least a portion of the pole ear portion 12 being folded from a first edge 22 of the transfer plate 2 to the first surface 21, and being welded to the first surface 21 to form a first welding area Domain 3, along the x-direction, the end of the pole ear portion 12 completely exceeds the first welding area 3; the pole 4 is welded to the first surface 21 of the adapter and forms a second welding area 5, and the end of the pole ear portion 12 is spaced apart from the pole 4; wherein, along the x-direction, the minimum distance between the edge of the first welding area 3 and the outer wall of the pole 4 is d, the maximum distance between the end of the pole ear portion 12 and the first edge 22 is b, and the minimum distance between the end of the pole ear portion 12 and the first edge 22 is a, satisfying -10mm≤d-(ba)≤30mm.

[0031] The battery of this embodiment reduces the risk of thermal runaway of the battery while ensuring the welding quality between the pole 4 and the adapter 2 and the flow capacity between the pole 4 and the adapter 2, thereby ensuring the safety performance of the battery.

[0032] Specifically, if d-(ba) is less than -10mm, there will be a greater risk of overlap between the end of the pole ear 12 and the pole 4, and the end of the pole ear 12 will be easily inserted between the pole 4 and the adapter plate 2. There is still a problem of poor welding between the pole 4 and the adapter plate 2, which will lead to poor welding quality between the pole 4 and the adapter plate 2, and thus affect the overcurrent capacity between the pole 4 and the adapter plate 2. In addition, it will also cause the area used for welding the pole ear 12 and the adapter plate 2 to be too small, which will affect the overcurrent capacity between the pole ear 12 and the adapter plate 2; if d-(ba) is greater than 30mm, the overcurrent transmission path from the pole ear 12 through the adapter plate 2 to the pole 4 will be too long, resulting in an excessively large internal resistance of the transmission path, causing the connection between the adapter plate 2 and the pole ear 12 to generate too much heat when transmitting current, which can easily cause thermal runaway of the battery and affect the safety performance of the battery.

[0033] Optionally, the value of d-(ba) is any value among -10mm, -9mm, -8mm, -7mm, -6mm, -5mm, -4mm, -3mm, -2mm, -1mm, 0, 2mm, 5mm, 8mm, 10mm, 12mm, 15mm, 18mm, 20mm, 22mm, 24mm, 25mm, 26mm, 28mm, 30mm, or a value between any two values.

[0034] It is worth noting that along the z-direction, the side of the adapter plate 2 opposite the first surface 21 is the second surface (i.e., the side of the adapter plate 2 closest to the cell body 11). In the related art, the pole ear 12 is welded to the second surface, and the pole 4 is welded to the first surface 21. In this case, although the end of the pole ear 12 is prevented from affecting the welding of the pole 4 and the adapter plate 2, the pole ear 12 is located between the adapter plate 2 and the cell body 11, requiring a larger height clearance.

[0035] In the present embodiment, the pole ear portion 12 is folded from the side close to the battery cell body 11 to the side away from the battery cell body 11 so that the pole ear portion 12 is welded to the first surface 21. However, since the pole 4 is also connected to the upper surface of the adapter 2 (i.e., the first surface 21), when the pole ear portion 12 is arranged on the upper surface of the adapter 2, the distance between the end of the pole ear portion 12 and the pole 4 will be too close, and the end of the pole ear portion 12 will easily be inserted between the pole 4 and the adapter 2. When the adapter 2 and the pole 4 are welded, the gap caused by the insertion of the pole ear portion 12 will cause the pole 4 and the adapter 2 to form a cold weld, resulting in poor welding quality between the pole 4 and the adapter 2, and affecting the flow capacity between the pole 4 and the adapter 2. Therefore, in this embodiment, by limiting the relationship between the minimum distance d between the edge of the first welding area 3 and the outer wall of the pole 4, the maximum distance b between the end of the pole ear 12 and the first edge 22, and the minimum distance a between the end of the pole ear 12 and the first edge 22, it is possible to improve the space utilization of the battery to improve the energy density of the battery, while ensuring the welding quality of the pole 4 and the adapter plate 2 to ensure the current flow capacity of the pole 4 and the adapter plate 2, and also ensuring the safety performance of the battery.

[0036] It should be noted that the tab 12 is the current output terminal of the battery cell 1. The tab 12 can be integrally connected to the battery cell body 11, or the independent tab 12 can be connected to the battery cell body 11 by welding, riveting, or the like.

[0037] It is worth noting that, in one embodiment, the battery cell 1 is formed or wound by a positive electrode sheet, a negative electrode sheet, and a separator sheet disposed therebetween. Therefore, a stacked battery cell body 11 and a tab portion 12 can be formed simultaneously. That is, the tab portion 12 includes a plurality of stacked tab sheets 27. When the multi-layer tab sheet 27 is folded from the side close to the battery cell body 11 to the side away from the battery cell body 11, the multi-layer tab sheet 27 is staggered at the end of the tab portion 12 so that the end surface of the tab portion 12 forms an inclined surface (see FIG. 1 ). Figure 4 and Figure 7 ), and the multi-layer tab body 27 gradually moves away from the pole 4 from the direction away from the first surface 21 to the direction close to the first surface 21, that is, see Figure 13 The distance between the end of the tab body 27 farthest from the first surface 21 and the first edge 22 is b, and the distance between the end of the tab body 27 closest to the first surface 21 and the first edge 22 is a.

[0038] For further explanation, please refer to Figure 7 The above-mentioned “the end of the pole tab portion 12 completely exceeds the first welding area 3” means that the end of the pole tab sheet 27 closest to the first surface 21 also needs to exceed the first welding area 3, thereby ensuring that the multiple layers of pole tab sheets 27 can completely accommodate the first welding area 3.

[0039] It can be understood that the end of the pole ear 12 connected to the battery cell body 11 is the root of the pole ear 12 , and correspondingly, the end of the pole ear 12 away from the battery cell body 11 is the end of the pole ear 12 .

[0040] It is worth noting that, please refer to Figure 3 The z direction is the height direction of the battery, that is, the direction perpendicular to the end face of the ear portion 12 of the battery cell body 11; the x direction is the width direction of the battery, that is, the thickness direction of the battery cell body 11, and the x direction and the z direction are perpendicular to each other.

[0041] It should be noted that the positive electrode sheet includes a positive electrode current collector and a positive electrode active material. The positive electrode current collector can be made of metal materials such as aluminum foil, nickel foil, stainless steel, or a composite foil formed by combining metal and insulating materials. The positive electrode active material includes a positive electrode active main material, a conductive agent, a binder, etc. The positive electrode active main material can include one or more lithium-containing positive electrode active materials such as lithium iron phosphate, a ternary material containing nickel, cobalt and manganese, and lithium iron manganese phosphate.

[0042] The negative electrode sheet includes a negative electrode current collector and a negative electrode active material. The negative electrode current collector can be made of metal materials such as copper foil, aluminum foil, stainless steel, or a composite foil formed by combining metal and insulating materials. The negative electrode active material includes a negative electrode active main material, a conductive agent, and a binder. The negative electrode active main material can include one or more of artificial graphite, natural graphite, silicon carbon, silicon oxide, lithium titanate, and other negative electrode active main materials.

[0043] In one embodiment, Figure 7 As shown, the minimum distance d between the edge of the first welding area 3 and the outer wall of the terminal 4 satisfies 5mm≤d≤30mm. This configuration ensures the welding quality between the terminal 4 and the adapter 2, as well as the current flow capacity between the terminal 4 and the adapter 2, while reducing the risk of thermal runaway of the battery and ensuring the battery's safety performance.

[0044] Specifically, if d is less than 5mm, there will be a greater risk of overlap between the end of the pole ear 12 and the pole 4, and the end of the pole ear 12 will easily be inserted between the pole 4 and the adapter plate 2. There is still a problem of poor welding between the pole 4 and the adapter plate 2, which will lead to poor welding quality between the pole 4 and the adapter plate 2, and thus affect the overcurrent capacity between the pole 4 and the adapter plate 2; if d is greater than 30mm, the overcurrent transmission path from the pole ear 12 through the adapter plate 2 to the pole 4 will be too long, resulting in excessive internal resistance of the transmission path, causing the connection part between the adapter plate 2 and the pole ear 12 to generate too much heat when transmitting current, which can easily cause thermal runaway of the battery and affect the safety performance of the battery.

[0045] Optionally, the value of d is any value among 5mm, 8mm, 10mm, 12mm, 15mm, 18mm, 20mm, 22mm, 25mm, 28mm, 30mm, or a value between any two values.

[0046] In one embodiment, Figure 13 As shown, the minimum distance a between the end of the pole lug 12 and the first edge 22 satisfies 5mm≤a≤20mm. This configuration ensures the welding quality between the pole 4 and the adapter 2, as well as the current flow capacity between the pole 4 and the adapter 2, while reducing the risk of thermal runaway of the battery and ensuring the battery's safety performance.

[0047] Specifically, if a is less than 5 mm, the area used for welding the pole ear portion 12 and the adapter plate 2 will be too small, which will affect the flow capacity between the pole ear portion 12 and the adapter plate 2; if a is greater than 20 mm, there will be a greater risk of overlap between the end of the pole ear portion 12 and the pole 4, and the end of the pole ear portion 12 will easily be inserted between the pole 4 and the adapter plate 2. There is still a problem of poor welding quality between the pole 4 and the adapter plate 2 due to cold welding, which will lead to poor welding quality between the pole 4 and the adapter plate 2, thereby affecting the flow capacity between the pole 4 and the adapter plate 2.

[0048] Optionally, the value of a is any value among 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, or a value between any two values.

[0049] In one embodiment, Figure 13 As shown, the maximum distance b between the end of the pole lug 12 and the first edge 22 satisfies 5mm≤b≤25mm. This ensures the welding quality between the pole 4 and the adapter 2, as well as the current flow capacity between the pole 4 and the adapter 2, while reducing the risk of thermal runaway of the battery and ensuring the safety performance of the battery.

[0050] Specifically, if b is less than 5 mm, the area used for welding the pole ear portion 12 and the adapter plate 2 will be too small, which will affect the flow capacity between the pole ear portion 12 and the adapter plate 2; if b is greater than 25 mm, there will be a greater risk of overlap between the end of the pole ear portion 12 and the pole 4, and the end of the pole ear portion 12 will easily be inserted between the pole 4 and the adapter plate 2. There is still a problem of poor welding quality between the pole 4 and the adapter plate 2 due to cold welding, which will lead to poor welding quality between the pole 4 and the adapter plate 2, thereby affecting the flow capacity between the pole 4 and the adapter plate 2.

[0051] Optionally, the value of b is any value of 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, or a value between any two values.

[0052] In one embodiment, Figure 11 and Figure 12 As shown, the adapter plate 2 has a weak area 23, and a fuse structure 24 is formed in the weak area 23. It should be noted that the fuse structure 24 can melt the adapter plate 2 when the battery generates too much heat, thereby disconnecting the pole ear portion 12 and the pole 4. In this embodiment, by limiting the relationship between the minimum distance d between the edge of the first welding area 3 and the outer wall of the pole 4, the maximum distance b between the end of the pole ear portion 12 and the first edge 22, and the minimum distance a between the end of the pole ear portion 12 and the first edge 22, it is possible to avoid the end of the pole ear portion 12 being too close to the pole 4, thereby avoiding the failure of the fuse structure 24 caused by the overlap of the pole ear portion 12 and the pole 4. When the battery generates a lot of heat, it is ensured that the fuse structure 24 can function, avoid the risk of thermal runaway of the battery, and ensure the safety performance of the battery.

[0053] It is worth noting that if the pole ear 12 overlaps the pole post 4, even if the fuse structure 24 melts and the pole ear 12 will not be electrically connected to the pole post 4 through the adapter 2, it will cause the pole ear 12 and the pole post 4 to be directly electrically connected and the pole ear 12 and the pole post 4 cannot be disconnected, which will cause the fuse structure 24 of the adapter 2 to fail, and the heat generation of the battery will continue to increase, leading to thermal runaway of the battery.

[0054] Please note that Figure 11 and Figure 12 The weak area 23 is usually formed by a hollow 25 (notch, through hole, etc.) or a thinned area provided on the adapter plate 2. Therefore, when an abnormality occurs inside the battery during the charge and discharge process, the fuse structure 24 can be melted by the rapid heat concentration, further disconnecting the current between the battery cell 1 and the terminal 4, that is, disconnecting the current between the output terminal of the battery cell 1 and the output terminal of the battery.

[0055] Furthermore, the minimum distance d between the edge of the first welding region 3 and the outer wall of the electrode 4, the maximum distance b between the end of the pole lug 12 and the first edge 22, and the minimum distance a between the end of the pole lug 12 and the first edge 22 all satisfy -5mm≤d-(ba)≤25mm. Because the adapter 2 has a fuse structure 24 that can fuse when the battery generates excessive heat, thereby ensuring the safety of the battery, the value of d-(ba) can be further limited. While further ensuring the distance between the end of the pole lug 12 and the electrode 4, the risk of overlap between the end of the pole lug 12 and the electrode 4 is further reduced, thereby further ensuring the welding quality between the electrode 4 and the adapter 2, as well as the current flow capacity between the electrode 4 and the adapter 2, while avoiding the problem of slowing the current transmission rate caused by the provision of the fuse structure on the adapter. In other words, by further controlling the value of d-(ba), the current transmission rate of the battery is guaranteed while ensuring the disconnection effect of the fuse structure.

[0056] In one embodiment, Figure 4As shown, along the z-direction, the adapter plate 2 protrudes toward the pole 4 to form a first protruding structure 26, and the orthographic projection of the first protruding structure 26 on the first surface 21 is at least partially overlapped with the orthographic projection of the pole 4 on the first surface 21. By forming the first protruding structure 26 on the adapter plate 2, the distance between the pole ear portion 12 and the pole 4 along the z-direction can be increased, further reducing the risk of overlap between the end of the pole ear portion 12 and the pole 4, thereby further preventing the end of the pole ear portion 12 from being inserted between the pole 4 and the adapter plate 2, thereby avoiding the problems of poor welding quality and poor current capacity caused by the occurrence of cold welding between the pole 4 and the adapter plate 2. In addition, the first protruding structure 26 itself has a small area (because it only occupies a small portion of the adapter plate 2), so the flatness of the first protruding structure 26 is easier to ensure, thereby further ensuring the welding quality and current capacity of the pole 4 and the adapter plate 2 (i.e., the first protruding structure 26).

[0057] It is worth noting that if Figure 9 and Figure 10 As shown, the adapter plate 2 includes a plate body 27 and the aforementioned first protruding structure 26. The first protruding structure 26 protrudes from a side surface of the plate body 27 along the z-direction. The first surface 21 includes a first sub-surface 211 and a second sub-surface 212. The side surface of the plate body 27 along the z-direction close to the first protruding structure 26 forms the first sub-surface 211, and the protruding surface of the first protruding structure 26 forms the second sub-surface 212. Furthermore, the pole lug 12 is welded to the first sub-surface 211, and at least a portion of the pole 4 is welded to at least a portion of the second sub-surface 212.

[0058] Furthermore, the minimum distance d between the edge of the first welding area 3 and the outer wall of the pole 4, the maximum distance b between the end of the pole ear 12 and the first edge 22, and the minimum distance a between the end of the pole ear 12 and the first edge 22 satisfy -10mm≤d-(ba)≤24mm. Because the setting of the first protruding structure 26 can further reduce the risk of the end of the pole ear 12 overlapping the pole 4, so as to further improve the welding quality and overcurrent capacity of the pole 4 and the adapter 2. Therefore, the value of d-(ba) can be further limited. Even if the distance between the edge of the first welding area 3 and the outer wall of the pole 4 is reduced, the end of the pole ear 12 can be avoided from overlapping the pole 4. At the same time, the overcurrent transmission path from the pole ear 12 through the adapter 2 to the pole 4 can be shortened, thereby further reducing the internal resistance of the transmission path, so as to further reduce the heat generated at the connection part between the adapter 2 and the pole ear 12 when transmitting current, further avoid the risk of thermal runaway of the battery, ensure the safety performance of the battery, and improve the current transmission rate of the battery, thereby improving the charge and discharge rate of the battery.

[0059] Specifically, in one embodiment, Figure 4As shown, on the first surface 21, along the z-direction, the portion corresponding to the first raised structure 26 protrudes by a height h relative to the non-protruding portion, satisfying 0.3mm≤h≤1mm. That is, along the z-direction, the distance between the second sub-surface 212 and the first sub-surface 211 is h. This arrangement further reduces the risk of overlap between the end of the tab 12 and the pole 4 while preventing the current transmission path between the battery cell 1 and the pole 4 from being excessively long, thereby affecting the current transmission rate.

[0060] It is worth noting that if the value of h is too small, the effect of increasing the distance between the end of the pole ear 12 and the pole 4 is not obvious, that is, the effect of reducing the risk of overlap between the end of the pole ear 12 and the pole 4 is not obvious; if the value of h is too large, the overcurrent transmission path from the pole ear 12 to the pole 4 through the adapter 2 is too long, that is, the current transmission path is too long, affecting the current transmission rate.

[0061] Optionally, the value of h is any value among 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, or a value between any two values.

[0062] Specifically, in one embodiment, Figure 15 As shown, the battery also includes a shell 9, which encloses a storage space, and the battery cell 1 is arranged in the storage space. The shell 9 is provided with a through hole, and the pole 4 is arranged corresponding to the through hole. The first protrusion structure 26 at least partially extends into the through hole in the z direction. That is, the pole 4 is not provided through the through hole (not inserted into the through hole at all or only partially inserted into the through hole), and the adapter 2 extends into the through hole through the first protrusion structure 26 to connect with the pole 4. Such an arrangement can further reduce the risk of overlap between the end of the pole ear 12 and the pole 4, thereby further avoiding the end of the pole ear 12 being inserted between the pole 4 and the adapter 2, and thus avoiding the problems of poor welding quality and poor current capacity caused by the occurrence of cold welding between the pole 4 and the adapter 2.

[0063] Furthermore, the minimum distance d between the edge of the first welding region 3 and the outer wall of the pole 4, the maximum distance b between the end of the pole ear 12 and the first edge 22, and the minimum distance a between the end of the pole ear 12 and the first edge 22 all satisfy -10mm≤d-(ba)≤22mm. By further limiting the value of d-(ba), even if the distance between the edge of the first welding region 3 and the outer wall of the pole 4 is reduced, the end of the pole ear 12 can be prevented from overlapping the pole 4. At the same time, the overcurrent transmission path from the pole ear 12 through the adapter 2 to the pole 4 can be shortened, thereby further reducing the internal resistance of the transmission path, further reducing the heat generated at the connection between the adapter 2 and the pole ear 12 during current transmission, further avoiding the risk of thermal runaway of the battery, ensuring the safety performance of the battery, and improving the current transmission rate of the battery, thereby improving the battery's charge and discharge rate.

[0064] Specifically, in one embodiment, Figure 1 and Figure 3 As shown, the housing 9 includes a cover plate 7 and a shell 8. Shell 8 is open at least at one end. The cover plate 7 is connected to the shell 8 and blocks the opening. The shell 8 and the cover plate 7 enclose a receiving space. Furthermore, the pole 4 can be disposed on the cover plate 7 or on the shell 8.

[0065] It is worth noting that the material of the housing 8 can be aluminum, aluminum alloy, copper, nickel, stainless steel, carbon steel, etc. The material of the pole 4 can be aluminum, aluminum alloy, copper-aluminum composite material, etc. The material of the adapter 2 can be aluminum, aluminum alloy, copper-aluminum composite material, etc.

[0066] Regarding the matching relationship between the pole 4 and the first protruding structure 26, in the first embodiment, as shown in FIG. Figure 16 As shown, the first end face 43 of the pole 4 is welded to the first surface 21 of the adapter plate 2 to form a second welding area 5, and the side of the first raised structure 26 near the end of the pole ear portion 12 extends beyond the side of the first end face 43 near the end of the pole ear portion 12. Specifically, the area of ​​the second sub-surface 212 is larger than the area of ​​the first end face 43, so that the pole 4 can be completely accommodated in the first raised structure 26 during welding. Such an arrangement can further reduce the risk of overlapping between the end of the pole ear portion 12 and the pole 4, thereby further preventing the end of the pole ear portion 12 from being inserted between the pole 4 and the adapter plate 2, thereby avoiding the problems of poor welding quality and poor current capacity caused by the occurrence of cold welding between the pole 4 and the adapter plate 2.

[0067] It is worth noting that the first end face 43 of the pole 4 is the side used for welding with the adapter 2, that is, Figure 4 and Figure 7 The bottom surface of the center pole 4 in the z direction.

[0068] In a first embodiment, if Figure 16 As shown, the area of ​​the first protrusion 26 facing the terminal 4 is S1, and the area of ​​the first end surface 43 of the terminal 4 is S2, satisfying 1.1≤S1 / S2≤3. This arrangement ensures both the flow capacity between the terminal 4 and the adapter 2 and the flow capacity between the terminal ear 12 and the adapter 2, thereby ensuring the current transmission effect of the entire battery.

[0069] It is worth noting that if the value of S1 / S2 is too small, the effect of increasing the distance between the end of the pole lug 12 and the pole 4 is not significant, that is, the effect of reducing the risk of overlap between the end of the pole lug 12 and the pole 4 is not significant. In addition, the area of ​​the first protruding structure 26 used for welding to the pole 4 will be too small, affecting the flow capacity between the pole 4 and the adapter 2. If the value of S1 / S2 is too large, the area occupied by the first protruding structure 26 will be too large, resulting in the area occupied by the sheet 27 being too small, resulting in the area of ​​the sheet 27 used for welding to the pole lug 12 being too small, affecting the flow capacity between the pole lug 12 and the adapter 2.

[0070] Optionally, the value of S1 / S2 is any value among 1.1, 1.3, 1.5, 1.8, 2, 2.3, 2.5, 2.8, 3, or a value between any two values.

[0071] It should be noted that the area of ​​the surface of the first protruding structure 26 facing the pole 4 is the area of ​​the second sub-surface 212 , that is, the area of ​​the second sub-surface 212 is S1 .

[0072] In the first embodiment, the area S1 of the first protrusion structure 26 facing the pole 4 satisfies 50 mm 2 ≤S1≤500mm 2 Such an arrangement can ensure both the welding area between the adapter plate 2 and the pole 4 and the welding area between the adapter plate 2 and the pole ear portion 12 .

[0073] It is worth noting that if the value of S1 is too small, the area of ​​the first protrusion structure 26 used for welding to the pole 4 is too small, affecting the flow capacity of the adapter plate 2 and the pole 4. If the value of S1 is too large, the area occupied by the first protrusion structure 26 is too large, resulting in the area occupied by the plate body 27 being too small, which will result in the area of ​​the plate body 27 used for welding to the pole lug portion 12 being too small, affecting the flow capacity between the pole lug portion 12 and the adapter plate 2.

[0074] Optionally, the value of S1 is 50mm 2 , 100mm 2 , 150mm 2 , 200mm 2 , 250mm 2 , 300mm2 , 350mm 2 , 400mm 2 , 450mm 2 , 500mm 2 Any value in , or a value between any two values.

[0075] In the first embodiment, the area S2 of the first end surface 43 of the pole 4 satisfies 40 mm 2 ≤S2≤300mm 2 Such an arrangement ensures the current carrying capacity of the pole 4 and the adapter 2 while facilitating the layout design of other components on the housing 9 .

[0076] It is worth noting that if the value of S2 is too small, the area of ​​the pole 4 used for welding to the adapter 2 is too small, affecting the flow capacity of the pole 4 and the adapter 2. If the value of S2 is too large, the space occupied by the pole 4 on the housing 9 is too large, which is not conducive to the arrangement of other components on the housing 9 (such as the liquid injection hole, explosion-proof valve, and QR code).

[0077] Optionally, the value of S2 is 40mm 2 , 80mm 2 , 120mm 2 , 180mm 2 , 220mm 2 , 280mm 2 , 300mm 2 Any value in , or a value between any two values.

[0078] In the first embodiment, the minimum distance d between the edge of the first welding region 3 and the outer wall of the pole 4, the maximum distance b between the end of the pole lug 12 and the first edge 22, and the minimum distance a between the end of the pole lug 12 and the first edge 22 satisfy -10mm≤d-(ba)≤26mm. By further limiting the value of d-(ba), even if the distance between the edge of the first welding region 3 and the outer wall of the pole 4 is reduced, the end of the pole lug 12 can be prevented from overlapping the pole 4. At the same time, the overcurrent transmission path from the pole lug 12 through the adapter 2 to the pole 4 can be shortened, thereby further reducing the internal resistance of the transmission path, further reducing the heat generated at the connection between the adapter 2 and the pole lug 12 during current transmission, further avoiding the risk of thermal runaway of the battery, ensuring the safety performance of the battery, and improving the current transmission rate and charge and discharge rate of the battery.

[0079] Regarding the matching relationship between the pole 4 and the first protruding structure 26, in the second embodiment, as shown in FIG. Figure 17As shown, the first end face 43 of the pole 4 is welded to the first surface 21 of the adapter plate 2 to form a second welding region 5. The side of the first raised structure 26 near the end of the pole ear 12 does not extend beyond the side of the first end face 43 near the end of the pole ear 12. Specifically, the area of ​​the second sub-surface 212 is less than or equal to the area of ​​the first end face 43. Therefore, during welding, the edge of the first raised structure 26 is flush with the edge of the pole 4, or the edge of the pole 4 extends beyond the edge of the first raised structure 26. This arrangement allows welding to be performed within the range of the first raised structure 26 to the pole 4, further facilitating welding of the adapter plate 2 and the pole 4.

[0080] It is worth noting that the first end face 43 of the pole 4 is the side used for welding with the adapter 2, that is, Figure 4 and Figure 7 The bottom surface of the center pole 4 in the z direction.

[0081] In a second embodiment, if Figure 17 As shown, the area of ​​the first protrusion 26 facing the terminal 4 is S3, and the area of ​​the first end surface 43 of the terminal 4 is S4, satisfying 0.2≤S3 / S4≤0.9. This arrangement ensures both the flow capacity between the terminal 4 and the adapter 2 and the flow capacity between the terminal lug 12 and the adapter 2, thereby ensuring the current transmission effect of the entire battery.

[0082] It is worth noting that if the value of S3 / S4 is too small, the distance between the end of the pole lug 12 and the pole 4 will be reduced, thereby increasing the risk of overlap between the end of the pole lug 12 and the pole 4. In addition, the area of ​​the first protrusion structure 26 used for welding to the pole 4 will be too small, affecting the flow capacity between the pole 4 and the adapter 2. If the value of S3 / S4 is too large, the area occupied by the first protrusion structure 26 will be too large, resulting in the area occupied by the plate 27 being too small, resulting in the area of ​​the plate 27 used for welding to the pole lug 12 being too small, affecting the flow capacity between the pole lug 12 and the adapter 2.

[0083] Optionally, the value of S3 / S4 is any value among 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or a value between any two values.

[0084] It should be noted that the area of ​​the surface of the first protruding structure 26 facing the pole 4 is the area of ​​the second sub-surface 212 , that is, the area of ​​the second sub-surface 212 is S3 .

[0085] In the second embodiment, the area S3 of the first protrusion structure 26 facing the pole 4 satisfies 40mm 2 ≤S3≤300mm 2Such an arrangement can ensure both the welding area between the adapter plate 2 and the pole 4 and the welding area between the adapter plate 2 and the pole ear portion 12 .

[0086] It is worth noting that if the value of S3 is too small, the area of ​​the first protrusion structure 26 used for welding to the pole 4 is too small, affecting the flow capacity of the adapter plate 2 and the pole 4. If the value of S3 is too large, the area occupied by the first protrusion structure 26 is too large, resulting in the area occupied by the plate body 27 being too small, which will result in the area of ​​the plate body 27 used for welding to the pole lug portion 12 being too small, affecting the flow capacity between the pole lug portion 12 and the adapter plate 2.

[0087] Optionally, the value of S3 is 40mm 2 , 80mm 2 , 120mm 2 , 180mm 2 , 220mm 2 , 280mm 2 , 300mm 2 Any value in , or a value between any two values.

[0088] In the second embodiment, the area S4 of the first end surface 43 of the pole 4 satisfies 50 mm 2 ≤S4≤500mm 2 Such an arrangement ensures the current carrying capacity of the pole 4 and the adapter 2 while facilitating the layout design of other components on the housing 9 .

[0089] It is worth noting that if the value of S4 is too small, the area of ​​the pole 4 used for welding to the adapter 2 is too small, affecting the flow capacity of the pole 4 and the adapter 2. If the value of S4 is too large, the space occupied by the pole 4 on the housing 9 is too large, which is not conducive to the arrangement of other components on the housing 9 (such as the liquid injection hole, explosion-proof valve, and QR code).

[0090] Optionally, the value of S4 is 50mm 2 , 100mm 2 , 150mm 2 , 200mm 2 , 250mm 2 , 300mm 2 , 350mm 2 , 400mm 2 , 450mm 2 , 500mm 2 Any value in , or a value between any two values.

[0091] In the second embodiment, the minimum distance d between the edge of the first welding region 3 and the outer wall of the electrode 4, the maximum distance b between the end of the electrode lug 12 and the first edge 22, and the minimum distance a between the end of the electrode lug 12 and the first edge 22 satisfy -7 mm ≤ d-(ba) ≤ 24 mm. By further limiting the value of d-(ba), the distance between the end of the electrode lug 12 and the electrode 4 is further guaranteed, further reducing the risk of overlap between the end of the electrode lug 12 and the electrode 4. This further ensures the welding quality between the electrode 4 and the adapter 2, as well as the current flow capacity between the electrode 4 and the adapter 2. This also avoids the problem of a current flow bottleneck between the adapter 2 and the electrode 4 caused by the first protrusion 26 not exceeding the range of the electrode 4, which in turn leads to a slow current transmission rate. In other words, by further controlling the value of d-(ba), the welding quality between the electrode 4 and the adapter 2 is guaranteed while also ensuring the current transmission rate of the battery.

[0092] In one embodiment, Figure 4 As shown, along the x-direction, the maximum distance between the first edge 22 and the tab 12 is e, satisfying 0 ≤ e ≤ 5 mm. This arrangement ensures the welding quality between the electrode 4 and the adapter 2, as well as the current carrying capacity between the electrode 4 and the adapter 2, while preventing the tab 12 from overlapping the battery casing and causing a short circuit.

[0093] It is worth noting that if e>5mm, please refer to Figure 6 The distance between the pole ear 12 and the first edge 22 of the adapter 2 is too far, and the pole ear 12 causes length redundancy at the first edge 22, causing the side of the pole ear 12 away from the first edge 22 to be more easily overlapped with the battery casing and cause a battery short circuit. In addition, the length of the pole ear 12 folded to the first surface 21 is too short, which easily leads to the area used for welding the pole ear 12 and the adapter 2 being too small, which will affect the flow capacity between the pole ear 12 and the adapter 2.

[0094] It should be further explained that, preferably, there is a certain distance between the first edge 22 and the pole ear portion 12 (ie, e>0). If the value of e is too small, please refer to Figure 5, the distance between the pole ear portion 12 and the first edge 22 of the adapter 2 is too close. When the pole ear portion 12 is bent at the first edge 22, the length of the pole ear portion 12 accommodated is shorter. Therefore, the length of the pole ear portion 12 folded onto the first surface 21 may be longer, resulting in the end of the pole ear portion 12 being closer to the pole 4, which may more easily cause the end of the pole ear portion 12 to overlap with the pole 4, causing the end of the pole ear portion 12 to be easily inserted between the pole 4 and the adapter 2. There is still a problem of poor welding between the pole 4 and the adapter 2, resulting in poor welding quality between the pole 4 and the adapter 2, which in turn affects the flow capacity between the pole 4 and the adapter 2. In addition, the pole ear portion 12 is more likely to be tightened when it is bent at the first edge 22, which may easily cause the pole ear portion 12 to tear, affecting the flow capacity of the pole ear portion 12.

[0095] Optionally, the value of e is any value among 0, 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, or a value between any two values.

[0096] In one embodiment, Figure 14 As shown, along the x-direction, the minimum distance c between the end of the pole lug 12 and the outer wall of the pole 4 satisfies 0≤c≤10mm. This arrangement ensures the welding quality between the pole 4 and the adapter 2, as well as the flow capacity between the pole 4 and the adapter 2, while reducing the risk of thermal runaway and ensuring battery safety.

[0097] Specifically, if c is less than 0, there will be a greater risk of overlap between the end of the pole ear 12 and the pole 4, and the end of the pole ear 12 will easily be inserted between the pole 4 and the adapter plate 2. There is still a problem of poor welding between the pole 4 and the adapter plate 2, which will lead to poor welding quality between the pole 4 and the adapter plate 2, and thus affect the overcurrent capacity between the pole 4 and the adapter plate 2; if c is greater than 10mm, the overcurrent transmission path from the pole ear 12 through the adapter plate 2 to the pole 4 will be too long, resulting in excessive internal resistance of the transmission path, causing the connection part between the adapter plate 2 and the pole ear 12 to generate too much heat when transmitting current, which can easily cause thermal runaway of the battery and affect the safety performance of the battery. In addition, it will also cause the area used for welding the pole ear 12 and the adapter plate 2 to be too small, which will affect the overcurrent capacity between the pole ear 12 and the adapter plate 2.

[0098] Optionally, the value of c is any value among 0, 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, or a value between any two values.

[0099] In one embodiment, Figure 4 As shown, the battery further includes a lower insulator 6. Along the z-direction, the lower insulator 6 is spaced relative to the first surface 21. Along the z-direction, the area of ​​the lower insulator 6 corresponding to the first welding region 3 at least partially protrudes in a direction away from the cell body 11 to form a second protruding structure 61. The second protruding structure 61 provides more accommodation space for the pole lug 12, allowing the pole lug 12 to be accommodated in the groove formed by the second protruding structure 61. This further increases the distance between the end of the pole lug 12 and the pole post 4, thereby further reducing the risk of overlap between the end of the pole lug 12 and the pole post 4, thereby further ensuring the welding quality between the pole post 4 and the adapter 2, as well as the flow capacity between the pole post 4 and the adapter 2.

[0100] In one embodiment, Figure 4 As shown, the cover plate 7 is disposed on the side of the lower insulating member 6 away from the cell body 11. Along the z-direction, the area of ​​the cover plate 7 corresponding to the second protruding structure 61 protrudes away from the cell body 11 to form a third protruding structure 71. By forming the third protruding structure 71 on the cover plate 7 to mate with the second protruding structure 61 of the lower insulating member 6 (i.e., the groove formed by the third protruding structure 71 accommodates the second protruding structure 61), the height of the remaining portion of the cover plate 7 along the z-direction can be minimized, thereby improving battery space utilization and ensuring battery energy density.

[0101] It is understandable that the lower insulating member 6 is located between the adapter plate 2 and the cover plate 7, thereby preventing the adapter plate 2 and the cover plate 7 from overlapping and causing a short circuit problem in the battery.

[0102] In one embodiment, Figure 4 and Figure 14 As shown, the pole 4 includes a first column segment 41 and a second column segment 42 connected along the z-direction. The first column segment 41 is connected to the first surface 21, and the second column segment 42 is arranged on the side of the first column segment 41 away from the first surface 21. Along the x-direction, the outer wall of the second column segment 42 protrudes from the outer wall of the first column segment 41, and the end of the pole lug 12 is arranged corresponding to the first column segment 41. In other words, the outer wall of the pole 4 forms a stepped structure. By reducing the size of the first column segment 41, the distance between the end of the pole lug 12 and the pole 4 can be further increased, thereby further reducing the risk of overlap between the end of the pole lug 12 and the pole 4, thereby further ensuring the welding quality between the pole 4 and the adapter 2, as well as the flow capacity between the pole 4 and the adapter 2.

[0103] For example, Figure 14 As shown, when the first column segment 41 and the second column segment 42 are both cylindrical, the first column segment 41 and the second column segment 42 are coaxially arranged, the diameter of the first column segment 41 is r1, and the diameter of the second column segment 42 is r2, and r1<r2 is satisfied.

[0104] It is worth noting that, in this embodiment, the z direction is the height direction of the battery, and the x direction is the width direction of the battery.

[0105] In one embodiment, Figure 3 and Figure 8 As shown, the adapter plate 2 has two first edges 22 arranged opposite to each other in the x-direction. The battery cells 1 are arranged in the x-direction with at least two first edges 22 arranged on opposite sides of the pole 4 in the x-direction. The tabs 12 of the battery cells 1 on opposite sides of the pole 4 are folded from the two first edges 22 to the first surface 21. Specifically, as Figure 3 As shown, two battery cells 1 are provided. The pole ear portion 12 of the battery cell 1 located on the left is folded from the left first edge 22 of the adapter plate 2 to the first surface 21, and the pole ear portion 12 of the battery cell 1 located on the right is folded from the right first edge 22 of the adapter plate 2 to the first surface 21. This arrangement can reduce the misalignment of the pole ear portion 12, thereby further reducing the risk of overlapping between the end of the pole ear portion 12 and the pole 4, thereby further ensuring the welding quality between the pole 4 and the adapter plate 2, and the current carrying capacity between the pole 4 and the adapter plate 2.

[0106] Furthermore, the minimum distance d between the edge of the first welding region 3 and the outer wall of the pole 4, the maximum distance b between the end of the pole ear 12 and the first edge 22, and the minimum distance a between the end of the pole ear 12 and the first edge 22 all satisfy -10mm≤d-(ba)≤24mm. By further limiting the value of d-(ba), even if the distance between the edge of the first welding region 3 and the outer wall of the pole 4 is reduced, the end of the pole ear 12 can be prevented from overlapping the pole 4. At the same time, the overcurrent transmission path from the pole ear 12 through the adapter 2 to the pole 4 can be shortened, thereby further reducing the internal resistance of the transmission path, further reducing the heat generated at the connection between the adapter 2 and the pole ear 12 during current transmission, further avoiding the risk of thermal runaway of the battery, ensuring the safety performance of the battery, and improving the current transmission rate of the battery, thereby improving the charge and discharge rate of the battery.

[0107] The present application is further described in detail below with reference to specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in this application.

[0108] The battery can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel metal hydride battery, a nickel cadmium battery, a lead storage battery, etc., which is not limited in this embodiment.

[0109] A battery typically includes a battery casing, a battery cell, a switching plate, and an electrolyte. The battery casing is used to hold the battery cell and electrolyte. The battery casing generally includes a shell and a cover. At least one positive electrode post and at least one negative electrode post are disposed on the shell and / or the cover. A battery cell includes one or more electrode assemblies. The electrode assembly is formed by stacking or winding a positive electrode sheet, a negative electrode sheet, and a separator. The separator is located between adjacent positive and negative electrode sheets to insulate the positive and negative electrode sheets. At least one end of the electrode assembly has a tab. One end of the switching plate is electrically connected to the tab, and the other end is electrically connected to the post.

[0110] Taking the wound cell as an example, the preparation methods of the example battery and the comparative example battery are as follows:

[0111] The positive electrode sheet, the negative electrode sheet and the diaphragm are wound to form an electrode assembly, and the pole ear portion is led out at one end of the electrode assembly. When the pole ear portion is fixed to the adapter, the electrode assembly and the pole ear portion are first placed along the pole ear portion leading-out direction, and then the pole ear portion of the electrode assembly is welded to the pole ear portion welding area of ​​the adapter, and then the pole column on the cover plate is welded to the pole column welding area of ​​the adapter. After welding is completed, the pole column and the pole ear portion are located on the same side in the thickness direction of the adapter, and then the electrode assembly is folded along the connection position between the pole ear portion and the electrode assembly so that the electrode assembly and the pole column are located on both sides in the thickness direction of the adapter, the folded electrode assembly is put into the shell, and the cover plate and the shell are welded and sealed, liquid is injected, formed, and the liquid injection hole is sealed to obtain a battery.

[0112] The dimensions of the battery of the embodiment and the battery of the comparative example are shown in Table 1. Other than that, the other characteristics of the batteries are the same. Furthermore, the relevant performances of the batteries in the above embodiment and the comparative example were tested, and the test results are recorded in Table 1. The test method is as follows:

[0113] 1. Battery overcurrent capacity test:

[0114] For each embodiment and comparative example, 10 batteries were taken respectively. The batteries were discharged to 0% SOC at 0.33C. After standing for 60 minutes, the temperature at this time was measured and recorded as t1. The batteries were charged to 100% SOC at 1C, the time was recorded as T, and the temperature at this time was measured and recorded as t2. The temperature rise rate was calculated according to the formula: temperature rise rate = (t2-t1) / T. If the temperature rise rate is greater than or equal to 0.9°C / min, it is unqualified. If the temperature rise rate is less than 0.9°C / min, it is qualified.

[0115] 2. Welding strength test:

[0116] For each embodiment and comparative example, 10 batteries were taken and tested using a universal tensile testing machine with the adapter fixed at one end and the pole fixed at the other end. The 90° peel strength between the pole and the adapter was tested. If the peel strength was greater than or equal to 400N, it was qualified; if the peel strength was less than 400N, it was unqualified.

[0117] Table 1:

[0118] d / mm b / mm a / mm d-(ba) / mm Temperature rise / (℃ / min) Peel strength / N Example 1 5 22.1 11.7 -5.4 0.6 406 Example 2 19.7 5 7.3 22 0.82 460 Example 3 25.1 24.9 5 5.2 0.69 439 Example 4 5.1 20.4 19.9 4.6 0.67 421 Example 5 5.6 20.5 10.5 -4.4 0.61 410 Example 6 29.9 5.1 5.1 29.9 0.9 473 Example 7 29.5 24.8 19.5 24.2 0.87 467 Example 8 27.1 25 5.1 7.2 0.71 441 Example 9 5 20.1 5.1 -10 0.56 401 Example 10 5.1 24.1 19.9 0.9 0.63 419 Example 11 4.8 5.1 20.1 19.8 0.78 458 Example 12 31.1 25.8 4.8 10.1 0.73 451 Example 13 5.1 15.4 4.1 -6.2 0.59 405 Example 14 4.2 20.1 6.8 -9.1 0.57 402 Example 15 11.2 4.5 15.9 22.6 0.83 461 Comparative Example 1 29.5 13 19.3 35.8 0.97 471 Comparative Example 2 25.1 14.3 21.5 32.3 0.95 469 Comparative Example 3 4.3 24.1 4.9 -14.9 0.54 395 Comparative Example 4 31.5 4.1 12.7 40.1 0.99 475 Comparative Example 5 30.1 4.7 21.1 46.5 1.1 478 Comparative Example 6 4.1 26.1 4.5 -17.5 0.52 391

[0119] As shown in Table 1, in Examples 1 to 15, the values ​​of d-(ba) are in the range of -10 mm to 30 mm, and the batteries of Examples 1 to 15 pass the overcurrent capacity test and the welding strength test.

[0120] As shown in Table 1, in Comparative Examples 1, 2, 4, and 5, the values ​​of d-(ba) were all greater than 30 mm. During the battery overcurrent capability test, the temperature rise of the batteries in Comparative Examples 1, 2, 4, and 5 exceeded 0.9°C / min, and the batteries failed the test. This indicates that setting d-(ba) ≤ 30 mm can reduce heat generation during current transmission between the battery cell and the electrode, thereby improving the overcurrent capability between the battery cell and the electrode.

[0121] As shown in Table 1, in Comparative Examples 3 and 6, the values ​​of d-(ba) were both less than -10 mm. During the welding strength test, the peel strength of the batteries in Comparative Examples 3 and 6 was less than 400 N, and they failed the welding strength test. This indicates that setting d-(ba) ≥ -10 mm can improve the welding quality and weld strength between the electrode and the adapter.

[0122] In summary, in the present application, by making -10 mm ≤ d-(ba) ≤ 30 mm, the welding quality and welding strength of the pole 4 and the adapter plate 2 are ensured while the current carrying capacity between the pole 4 and the adapter plate 2 is improved.

[0123] According to an embodiment of the present invention, in a second aspect, there is provided an electrical device comprising the above-mentioned battery, wherein at least two batteries are provided, and poles of at least two adjacent batteries are electrically connected via a conductive bus.

[0124] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A battery, characterized in that: include: A battery cell (1) comprises a battery cell body (11) and a pole ear portion (12), wherein the pole ear portion (12) extends from at least one end of the battery cell body (11), and the pole ear portion (12) is electrically connected to the battery cell body (11); A transfer plate (2) is spaced apart from the battery cell body (11) along the z direction, a side of the transfer plate (2) away from the battery cell body (11) forms a first surface (21), at least a portion of the pole ear portion (12) is folded from a first edge (22) of the transfer plate (2) to the first surface (21), and is welded to the first surface (21) to form a first welding area (3), and an end of the pole ear portion (12) completely exceeds the first welding area (3) along the x direction; A pole (4) is welded to the first surface (21) of the adapter plate (2) to form a second welding area (5), and an end of the pole ear portion (12) is spaced apart from the pole (4); Wherein, along the x direction, the minimum distance between the edge of the first welding area (3) and the outer wall of the pole (4) is d, the maximum distance between the end of the pole ear (12) and the first edge (22) is b, and the minimum distance between the end of the pole ear (12) and the first edge (22) is a, satisfying -10mm≤d-(ba)≤30mm.

2. The battery according to claim 1, characterized in that The adapter plate (2) has a weak area (23), and a fuse structure (24) is formed in the weak area (23).

3. The battery according to claim 2, characterized in that The minimum distance d between the edge of the first welding area (3) and the outer wall of the pole (4), the maximum distance b between the end of the pole ear (12) and the first edge (22), and the minimum distance a between the end of the pole ear (12) and the first edge (22) satisfy -5mm≤d-(ba)≤25mm.

4. The battery according to claim 1, characterized in that Along the z direction, the adapter plate (2) protrudes toward the pole (4) to form a first protruding structure (26), and the orthographic projection of the first protruding structure (26) on the first surface (21) and the orthographic projection of the pole (4) on the first surface (21) are at least partially overlapped.

5. The battery according to claim 4, characterized in that The minimum distance d between the edge of the first welding area (3) and the outer wall of the pole (4), the maximum distance b between the end of the pole ear (12) and the first edge (22), and the minimum distance a between the end of the pole ear (12) and the first edge (22) satisfy -10mm≤d-(ba)≤24mm.

6. The battery according to claim 4, characterized in that On the first surface (21), along the z direction, the protruding height of the portion corresponding to the first protruding structure (26) relative to the non-protruding portion is h, satisfying 0.3 mm ≤ h ≤ 1 mm.

7. The battery according to claim 4, characterized in that The first end face (43) of the pole (4) is welded to the first surface (21) of the adapter plate (2) to form the second welding area (5), and the side of the first protruding structure (26) close to the end of the pole ear (12) extends beyond the side of the first end face (43) close to the end of the pole ear (12).

8. The battery according to claim 7, characterized in that The area of ​​the side of the first protruding structure (26) facing the pole (4) is S1, and the area of ​​the first end surface (43) of the pole (4) is S2, satisfying 1.1≤S1 / S2≤3.

9. The battery according to claim 8, characterized in that The area S1 of the first protruding structure (26) facing the pole (4) satisfies 50 mm 2 ≤S1≤500mm 2 and / or, The area S2 of the first end surface (43) of the pole (4) satisfies 40 mm 2 ≤S2≤300mm 2 .

10. The battery according to claim 7, characterized in that The minimum distance d between the edge of the first welding area (3) and the outer wall of the pole (4), the maximum distance b between the end of the pole ear (12) and the first edge (22), and the minimum distance a between the end of the pole ear (12) and the first edge (22) satisfy -10mm≤d-(ba)≤26mm.

11. The battery according to claim 4, characterized in that The first end face (43) of the pole (4) is welded to the first surface (21) of the adapter plate (2) to form the second welding area (5), and the side of the first protruding structure (26) close to the end of the pole ear (12) does not extend beyond the side of the first end face (43) close to the end of the pole ear (12).

12. The battery according to claim 11, characterized in that The area of ​​the side of the first protruding structure (26) facing the pole (4) is S3, and the area of ​​the first end surface (43) of the pole (4) is S4, satisfying 0.2≤S3 / S4≤0.

9.

13. The battery according to claim 12, characterized in that The area S3 of the first protruding structure (26) facing the pole (4) satisfies 40 mm 2 ≤S3≤300mm 2 and / or, The area S4 of the first end surface (43) of the pole (4) satisfies 50 mm 2 ≤S4≤500mm 2 .

14. The battery according to claim 11, characterized in that The minimum distance d between the edge of the first welding area (3) and the outer wall of the pole (4), the maximum distance b between the end of the pole ear (12) and the first edge (22), and the minimum distance a between the end of the pole ear (12) and the first edge (22) satisfy -7mm≤d-(ba)≤24mm.

15. The battery according to claim 4, characterized in that The battery further comprises a housing (9), the housing (9) enclosing a receiving space, the battery cell (1) being arranged in the receiving space, the housing (9) being provided with a through hole, the pole (4) being arranged corresponding to the through hole, and at least a portion of the first protrusion structure (26) in the z direction extending into the through hole.

16. The battery according to claim 15, characterized in that The minimum distance d between the edge of the first welding area (3) and the outer wall of the pole (4), the maximum distance b between the end of the pole ear (12) and the first edge (22), and the minimum distance a between the end of the pole ear (12) and the first edge (22) satisfy -10mm≤d-(ba)≤22mm.

17. The battery according to any one of claims 1 to 16, characterized in that Along the x direction, the maximum distance between the first edge (22) and the pole ear portion (12) is e, satisfying 0≤e≤5mm.

18. The battery according to any one of claims 1 to 16, characterized in that Along the x direction, the minimum distance between the end of the pole ear (12) and the outer wall of the pole (4) is c, satisfying 0≤c≤10mm.

19. The battery according to any one of claims 1 to 16, characterized in that The battery further comprises a lower insulating member (6), wherein the lower insulating member (6) is spaced relative to the first surface (21) along the z direction, and along the z direction, an area of ​​the lower insulating member (6) corresponding to the first welding area (3) is at least partially protruded in a direction away from the battery cell body (11) to form a second protruding structure (61).

20. The battery according to claim 19, characterized in that The battery further comprises a cover plate (7), the cover plate (7) being arranged on a side of the lower insulating member (6) away from the battery cell body (11), and along the z direction, an area of ​​the cover plate (7) corresponding to the second protruding structure (61) is protruded in a direction away from the battery cell body (11) to form a third protruding structure (71).

21. The battery according to any one of claims 1 to 16, characterized in that The pole (4) comprises a first pole segment (41) and a second pole segment (42) connected and arranged along the z direction, the first pole segment (41) is connected to the first surface (21), the second pole segment (42) is arranged on a side of the first pole segment (41) away from the first surface (21), and along the x direction, the outer wall of the second pole segment (42) protrudes from the outer wall of the first pole segment (41), and the end of the pole ear portion (12) is arranged corresponding to the first pole segment (41).

22. The battery according to claim 1, characterized in that The minimum distance d between the edge of the first welding area (3) and the outer wall of the pole (4) satisfies 5mm≤d≤30mm.

23. The battery according to claim 1, characterized in that The minimum distance a between the end of the pole lug (12) and the first edge (22) satisfies 5mm≤a≤20mm.

24. The battery according to claim 1, characterized in that The maximum distance b between the end of the pole lug (12) and the first edge (22) satisfies 5mm≤b≤25mm.

25. The battery according to any one of claims 1 to 16, characterized in that The adapter plate (2) has two first edges (22) arranged opposite to each other in the x-direction, and at least two of the battery cells (1) are arranged along the x-direction and are arranged on opposite sides of the pole (4) along the x-direction, and the pole ears (12) of the battery cells (1) located on opposite sides of the pole (4) are folded from the two first edges (22) to the first surface (21) respectively.

26. The battery according to claim 25, characterized in that The minimum distance d between the edge of the first welding area (3) and the outer wall of the pole (4), the maximum distance b between the end of the pole ear (12) and the first edge (22), and the minimum distance a between the end of the pole ear (12) and the first edge (22) satisfy -10mm≤d-(ba)≤24mm.

27. An electrical device, characterized in that: A battery comprising any one of claims 1 to 26, wherein the battery is provided with at least two poles (4), and the poles (4) of at least two adjacent batteries are electrically connected via a conductive bus.

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