Battery, battery assembly, and electric device

Abstract

This utility model discloses a battery, a battery assembly, and an electrical device. The battery includes: a battery cell, which includes a positive electrode tab and a negative electrode tab; a positive electrode busbar disposed on one side of the battery cell in the height direction, which includes a positive electrode connection portion electrically connected to the positive electrode tab; and a negative electrode busbar disposed on the other side of the battery cell in the height direction, which includes a negative electrode connection portion electrically connected to the negative electrode tab. In the height direction of the battery cell, the orthographic projections of the positive electrode connection portion and the negative electrode connection portion are at least partially offset. Therefore, by making the orthographic projections of the positive electrode connection portion and the negative electrode connection portion at least partially offset from each other in the height direction of the battery cell, the movement path of charge within the positive and negative electrode busbars can be extended, optimizing the heat and charge distribution within the battery. This avoids the risk of performance degradation or failure caused by high charge density areas of the positive and negative electrodes being directly opposite each other.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery, battery assembly, and electrical equipment. Background Technology

[0002] To meet the demands of high-rate charging and discharging, the electrodes of large cylindrical batteries are typically designed with a multi-tab structure to reduce internal resistance.

[0003] In related technologies, multiple tabs are cut out from the empty foil area at the edge of the dressing to form a multi-tab structure. Although the multi-tab structure can effectively reduce the overall resistance of the cell and improve the overcurrent capacity of the cell, the densely distributed multi-tabs can easily cause excessive charge density at the edge in the early stage of charging, leading to lithium and sodium plating. In addition, in the late stage of charging, the increased charge density and decreased potential in the tabless area can also lead to failure. Utility Model Content

[0004] The present invention aims to at least solve one of the technical problems existing in the prior art. Therefore, one objective of the present invention is to provide a reliable battery that reduces the risk of battery failure.

[0005] This utility model further proposes a battery assembly.

[0006] This utility model further proposes an electrical device.

[0007] The battery according to this utility model includes: a battery cell, the battery cell including a positive electrode tab and a negative electrode tab; a positive electrode busbar disposed on one side of the battery cell in the height direction, the positive electrode busbar including a positive electrode connection portion electrically connected to the positive electrode tab; and a negative electrode busbar disposed on the other side of the battery cell in the height direction, the negative electrode busbar including a negative electrode connection portion electrically connected to the negative electrode tab; in the height direction of the battery cell, the orthographic projections of the positive electrode connection portion and the orthographic projections of the negative electrode connection portion are at least partially offset.

[0008] Therefore, by making the orthogonal projections of the positive electrode connection and the negative electrode connection at least partially offset from each other in the height direction of the cell, the charge movement path between the positive electrode busbar and the negative electrode busbar can be extended, the heat distribution and charge distribution in the battery can be optimized, and the risk of battery performance degradation or failure caused by the positive and negative electrode high charge density areas facing each other can be avoided.

[0009] In some examples of this utility model, the orthographic projections of the positive electrode connection and the negative electrode connection are completely misaligned in the height direction of the battery cell.

[0010] In some examples of this utility model, the positive electrode busbar includes a plurality of spaced-apart positive electrode connection portions, and the negative electrode busbar includes a plurality of spaced-apart negative electrode connection portions. In the height direction of the battery cell, at least some of the orthogonal projections of the positive electrode connection portions and the orthogonal projections of the negative electrode connection portions are completely misaligned; and / or at least some of the orthogonal projections of the negative electrode connection portions and the orthogonal projections of the positive electrode connection portions are completely misaligned.

[0011] In some examples of this invention, the orthographic projections of at least a portion of the positive electrode connection and at least a portion of the negative electrode connection in the height direction of the battery cell are alternately spaced along the circumference of the battery cell.

[0012] In some examples of this utility model, there are two positive electrode connection portions and two negative electrode connection portions. In the height direction of the battery cell, the orthographic projections of the two positive electrode connection portions are arranged opposite each other on the first radial direction of the battery cell, and the orthographic projections of the two negative electrode connection portions are arranged opposite each other on the second radial direction of the battery cell. The first radial direction and the second radial direction of the battery cell are at an angle to each other on the same plane.

[0013] In some examples of this invention, the first radial direction and the second radial direction of the battery cell are perpendicular to each other in the same plane.

[0014] In some examples of this utility model, the positive electrode connection includes a first positive electrode welding section and a second positive electrode welding section, wherein the extension direction of the first positive electrode welding section and the extension direction of the second positive electrode welding section are at an angle α, and the value of α is in the range of 0°≤α≤95°; and / or the negative electrode connection includes a first negative electrode welding section and a second negative electrode welding section, wherein the extension direction of the first negative electrode welding section and the extension direction of the second negative electrode welding section are at an angle β, and the value of β is in the range of 0°≤β≤95°.

[0015] In some examples of this utility model, there are three positive electrode connection portions and three negative electrode connection portions. In the height direction of the battery cell, the orthographic projections of the three positive electrode connection portions and the orthographic projections of the three negative electrode connection portions are alternately and spaced apart in the circumferential direction of the battery cell.

[0016] In some examples of this utility model, the positive electrode connection includes a first positive electrode welding section and a second positive electrode welding section, wherein the extension direction of the first positive electrode welding section and the extension direction of the second positive electrode welding section are at an angle α, and the value of α is in the range of 0°≤α≤65°; and / or the negative electrode connection includes a first negative electrode welding section and a second negative electrode welding section, wherein the extension direction of the first negative electrode welding section and the extension direction of the second negative electrode welding section are at an angle β, and the value of β is in the range of 0°≤β≤65°.

[0017] In some examples of this utility model, in the thickness direction of the positive electrode busbar, the minimum distance between the orthographic projection of the positive electrode connection and the center of the outer contour of the orthographic projection of the positive electrode busbar is L1, and the value range of L1 is: L1≥3mm; and / or the minimum distance between the negative electrode connection and the center of the negative electrode busbar is L2, and the value range of L2 is: L2≥3mm.

[0018] In some examples of this utility model, the edge of the positive electrode busbar is provided with a positive electrode positioning part, and the edge of the negative electrode busbar is provided with a negative electrode positioning part. The negative electrode positioning part and the positive electrode positioning part are positioned and cooperated so that the orthographic projections of the positive electrode connection part and the negative electrode connection part in the height direction are at least partially misaligned.

[0019] In some examples of this utility model, in the height direction of the battery cell, the orthogonal projection of the positive electrode positioning portion and the orthogonal projection of the negative electrode positioning portion at least partially overlap.

[0020] In some examples of this utility model, in the height direction of the battery cell, the orthogonal projection of the negative electrode positioning part and the orthogonal projection of the negative electrode connection part are spaced apart; and / or the orthogonal projection of the positive electrode positioning part and the orthogonal projection of the positive electrode connection part are spaced apart.

[0021] In some examples of this utility model, the battery cell includes a positive electrode sheet and a negative electrode sheet stacked along a first direction. The positive electrode sheet has a positive electrode tab at one end in the height direction of the battery cell, and the negative electrode sheet has a negative electrode tab at one end in the height direction of the battery cell away from the positive electrode tab. The positive electrode sheet includes a positive electrode coating area, and the negative electrode sheet includes a negative electrode coating area. In the first direction, the orthographic projection of the positive electrode coating area is located within the orthographic projection of the negative electrode coating area.

[0022] In some examples of this utility model, the positive electrode and the negative electrode are wound along a second direction to form the battery cell. One end of the positive electrode in the second direction is set as the initial end of the positive winding. The minimum distance between the positive electrode tab and the initial end of the positive winding along the second direction is greater than the minimum distance between the negative electrode tab and the initial end of the positive winding along the second direction.

[0023] In some examples of this invention, the total flow area of ​​the negative electrode tab is greater than or equal to the total flow area of ​​the positive electrode tab.

[0024] In some examples of this utility model, before winding, in the second direction, there are multiple negative tabs spaced apart along the second direction, and multiple positive tabs spaced apart along the second direction. Before winding, in the second direction, the minimum distance between two adjacent positive tabs is L6, and the minimum distance between two adjacent negative tabs is L7. L6 and L7 satisfy the relationship: L6≥L7; and / or before winding, in the second direction, the maximum size of the positive tab is L8, and the maximum size of the negative tab is L9, with L8≤L9; and / or before winding, in the height direction of the cell, the maximum size of the positive tab is L10, and the maximum size of the negative tab is L11, with L11≥L10.

[0025] The battery assembly according to this utility model includes the battery described above, and a circuit structure, wherein the battery is electrically connected to the circuit structure.

[0026] The electrical device according to this utility model includes the battery described above, and / or includes the battery assembly described above.

[0027] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0028] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0029] Figure 1 This is a schematic diagram of the stacking of positive and negative electrode sheets of a battery according to an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of the positive electrode tab according to an embodiment of the present utility model;

[0031] Figure 3 This is a schematic diagram of the negative electrode tab according to an embodiment of the present utility model;

[0032] Figure 4 This is a schematic diagram of the positive electrode busbar according to the first embodiment of the present utility model;

[0033] Figure 5 This is a schematic diagram of the negative electrode busbar according to the first embodiment of the present utility model;

[0034] Figure 6 This is a schematic diagram of the positive electrode busbar according to the second embodiment of the present utility model;

[0035] Figure 7 This is a schematic diagram of the negative electrode busbar according to the second embodiment of the present utility model;

[0036] Figure 8 This is a schematic diagram showing the projection of the positive electrode connection portion and the negative electrode connection portion in the vertical direction according to the second embodiment of the present utility model.

[0037] Figure 9 This is a schematic diagram of a battery according to an embodiment of the present invention.

[0038] Figure label:

[0039] 100. Battery;

[0040] 10. Battery cell; 101. Positive electrode sheet; 1011. Positive electrode tab; 1012. Positive electrode coating area; 1014. Initial end of positive electrode winding; 1015. Boehmite coating layer; 102. Negative electrode sheet; 1021. Negative electrode tab; 1022. Negative electrode coating area; 1024. Initial end of negative electrode winding;

[0041] 201. Positive electrode busbar; 2011. Positive electrode connection part; 2012. First positive electrode welding section; 2013. Second positive electrode welding section; 2014. Positive electrode positioning part; 202. Negative electrode busbar; 2021. Negative electrode connection part; 2022. First negative electrode welding section; 2023. Second negative electrode welding section; 2024. Negative electrode positioning part; 2025. Bending connector; 21. Injection hole; 22. Electrolyte permeation reserved hole. Detailed Implementation

[0042] The embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The embodiments of the present invention are described in detail below.

[0043] The following is for reference. Figures 1-9 The battery 100 according to an embodiment of the present invention can be applied to battery modules and / or electrical devices.

[0044] Combination Figures 1-9 As shown, the battery 100 according to this utility model mainly includes: a battery cell 10, a positive electrode busbar 201, and a negative electrode busbar 202. The battery cell 10 includes a positive electrode tab 1011 and a negative electrode tab 1021. The positive electrode busbar 201 is disposed on one side of the battery cell 10 in the height direction and includes a positive electrode connection portion 2011, which is electrically connected to the positive electrode tab 1011. The negative electrode busbar 202 is disposed on the other side of the battery cell 10 in the height direction and includes a negative electrode connection portion 2021, which is electrically connected to the negative electrode tab 1021. In the height direction of the battery cell 10, the orthographic projections of the positive electrode connection portion 2011 and the negative electrode connection portion 2021 are at least partially offset.

[0045] Specifically, by placing the positive electrode busbar 201 on one side of the cell 10 in the height direction and placing the negative electrode busbar 202 on the other side of the cell 10 in the height direction, the positive electrode connection portion 2011 on the positive electrode busbar 201 and the positive electrode tab 1011 can be electrically connected, and the negative electrode connection portion 2021 on the negative electrode busbar 202 and the negative electrode tab 1021 can be electrically connected, thereby realizing the input and output of current of the battery 100. This can reduce the loss in the current transmission process, ensure the high efficiency of current transmission, and optimize the performance of the battery 100.

[0046] Furthermore, in the height direction of the cell 10, the orthographic projections of the positive electrode connection portion 2011 and the negative electrode connection portion 2021 are at least partially offset. This allows for a layout in which the positive electrode connection portion 2011 of the positive electrode busbar 201 and the negative electrode connection portion 2021 of the negative electrode busbar 202 are at least partially misaligned in the vertical direction. This not only extends the charge movement path between the positive electrode busbar 201 and the negative electrode busbar 202, optimizing the heat and charge distribution within the battery 100, but also avoids the risk of performance degradation or failure of the battery 100 caused by the high charge density regions of the positive and negative electrodes being directly opposite each other, thereby improving the structural stability and performance of the battery 100.

[0047] It should be noted that the height direction of the cell 10 is also the relative direction of the positive tab 1011 and the negative tab 1021. For example, when the cell 10 is a cylindrical cell, the height direction of the cell 10 is the axial direction of the cell 10.

[0048] In addition, in some embodiments of this utility model, the positive electrode tab 1011 and the positive electrode connection portion 2011 can be electrically connected by welding, and the negative electrode tab 1021 and the negative electrode connection portion 2021 can be electrically connected by welding. This not only improves the electrical connection stability between the positive electrode tab 1011 and the positive electrode connection portion 2011, but also improves the electrical connection stability between the negative electrode tab 1021 and the negative electrode connection portion 2021. Furthermore, it reduces the difficulty of electrically connecting the positive electrode tab 1011 and the positive electrode connection portion 2011, and also reduces the difficulty of electrically connecting the negative electrode tab 1021 and the negative electrode connection portion 2021.

[0049] It should be noted that the welding wires on the positive electrode connection 2011 and / or the negative electrode connection 2021 may be, but are not limited to, straight, spiral, and circular.

[0050] In some other embodiments of this utility model, in order to prevent the high charge density regions of the positive and negative electrodes from being directly opposite each other, causing the battery 100 to experience performance degradation or failure, the positive projection of the positive electrode tab 1011 and the positive projection of the negative electrode tab 1021 can be at least partially offset in the height direction of the cell 10.

[0051] In some embodiments of this utility model, the materials of the negative electrode busbar 202 and the positive electrode busbar 201 include, but are not limited to, copper, plating, nickel and aluminum.

[0052] Therefore, by at least partially offsetting the orthographic projections of the positive electrode connection 2011 and the negative electrode connection 2021 from each other in the height direction of the cell 10, the charge movement path between the positive electrode busbar 201 and the negative electrode busbar 202 can be extended, the heat distribution and charge distribution within the battery 100 can be optimized, and the risk of performance degradation or failure of the battery 100 caused by the positive and negative electrode high charge density regions being directly opposite each other can be avoided.

[0053] In some embodiments of this utility model, the positive electrode busbar 201 is a positive electrode busbar, and the positive electrode busbar is covered on one side of the battery cell 10 in the height direction. The negative electrode busbar 202 is a negative electrode busbar, and the negative electrode busbar is covered on the other side of the battery cell 10 in the height direction.

[0054] In some embodiments of this utility model, the battery 100 further includes a positive electrode external cover and / or a negative electrode external cover. The positive electrode bus 201 and / or the negative electrode bus 202 are connected to a bending connector 2025. The bending connector 2025 is bendable relative to the positive electrode bus 201 and / or the negative electrode bus 202. When the positive electrode external cover is placed on the positive electrode bus 201, the bending connector 2025 connected to the positive electrode bus 201 can be bent to achieve electrical connection with the positive electrode external cover. When the negative electrode external cover is placed on the negative electrode bus 202, the bending connector 2025 connected to the negative electrode bus 202 can be bent to achieve electrical connection with the negative electrode external cover. Thus, electrical connection with an external circuit is achieved through the positive electrode external cover and / or the negative electrode external cover.

[0055] In some embodiments of this utility model, both the negative electrode bus 202 and the positive electrode bus 201 are circular, and the orthographic projections of the centers of the negative electrode bus 202 and the positive electrode bus 201 in the height direction of the battery cell 10 coincide with each other. Furthermore, the diameters of the negative electrode bus 202 and the positive electrode bus 201 are the same, and the bent connector 2025 is rectangular.

[0056] Furthermore, an injection hole 21 is provided at the center of the outer contour of the positive electrode busbar 201 and the negative electrode busbar 202. After the battery cell 10 is wound, an electrolyte channel can be formed in the middle. The electrolyte channel extends in the height direction of the battery cell 10. The injection holes 21 on the positive electrode busbar 201 and the negative electrode busbar 202 are connected to the electrolyte channel.

[0057] In addition, the positive electrode busbar 201 and the negative electrode busbar 202 may also be provided with elongated and / or circular electrolyte permeation pre-reserved holes 22 to improve the permeation effect of electrolyte in the battery 100. It should be noted that on the positive electrode busbar 201, the electrolyte permeation pre-reserved holes 22, the injection hole 21 and the positive electrode connection portion 2011 are spaced apart from each other, and on the negative electrode busbar 202, the electrolyte permeation pre-reserved holes 22, the injection hole 21 and the negative electrode connection portion 2021 are spaced apart from each other.

[0058] In some embodiments of this utility model, the structural design of the battery 100 can be used not only for cylindrical batteries, but also for multi-tab batteries of other configurations. The types of the battery 100 include, but are not limited to, pouch batteries, square aluminum-cased batteries, steel-cased batteries, etc.

[0059] Combination Figure 8 As shown, in the height direction of the cell 10, the orthogonal projections of the positive electrode connection 2011 and the negative electrode connection 2021 are completely offset. Specifically, by setting the projections of the positive electrode connection 2011 and the negative electrode connection 2021 in the height direction of the cell 10 to be completely offset, there is no overlapping area between the projections of the positive electrode connection 2011 and the negative electrode connection 2021 in the height direction of the cell 10. This further extends the charge movement path within the battery 100, further optimizes the heat and charge distribution within the battery 100, and more effectively avoids the risk of performance degradation or failure of the battery 100 caused by high charge density areas of the positive and negative electrodes facing each other.

[0060] Combination Figures 4-8 As shown, the positive electrode busbar 201 includes a plurality of spaced-apart positive electrode connection portions 2011, and the negative electrode busbar 202 includes a plurality of spaced-apart negative electrode connection portions 2021. In the height direction of the cell 10, the orthographic projections of at least a portion of the positive electrode connection portions 2011 and the orthographic projections of the negative electrode connection portions 2021 are completely misaligned; and / or the orthographic projections of at least a portion of the negative electrode connection portions 2021 and the orthographic projections of the positive electrode connection portions 2011 are completely misaligned. Specifically, by providing a plurality of spaced-apart positive electrode connection portions 2011 on the positive electrode busbar 201 and a plurality of spaced-apart negative electrode connection portions 2021 on the negative electrode busbar 202, the area of ​​electrical connection between the positive electrode busbar 201 and the positive electrode tab 1011 can be increased, and the area of ​​electrical connection between the negative electrode busbar 202 and the positive electrode tab 1011 can also be increased, thereby improving the overcurrent capacity of the battery 100.

[0061] Based on this, the orthographic projections of at least a portion of the positive electrode connection portion 2011 and the negative electrode connection portion 2021 are completely offset in the height direction of the cell 10, and the orthographic projections of at least a portion of the positive electrode connection portion 2011 and the negative electrode connection portion 2021 are completely offset in the height direction of the cell 10. That is, one or more of the multiple positive electrode busbars 201 can be offset from one or more of the multiple negative electrode busbars 202. This can improve the overcurrent capacity of the battery 100 while still effectively avoiding the risk of performance degradation or failure of the battery 100 caused by the positive and negative electrode high charge density regions being directly opposite each other, thereby improving the performance and reliability of the battery 100.

[0062] Combination Figure 8 As shown, at least a portion of the orthographic projection of the positive electrode connection portion 2011 and at least a portion of the orthographic projection of the negative electrode connection portion 2021 in the height direction of the cell 10 are alternately spaced along the circumference of the cell 10. This can improve the overcurrent capacity of the battery 100 while further avoiding the risk of performance degradation or failure of the battery 100 caused by the positive and negative electrode high charge density areas being directly opposite each other. This not only improves the performance and reliability of the battery 100, but also makes full use of the space in the circumference of the cell 10, thereby improving space utilization.

[0063] Combination Figure 4 and Figure 5 As shown, there are two positive electrode connection portions 2011 and two negative electrode connection portions 2021. In the height direction of the cell 10, the orthographic projections of the two positive electrode connection portions 2011 are arranged opposite each other in the first radial direction of the cell 10, and the orthographic projections of the two negative electrode connection portions 2021 are arranged opposite each other in the second radial direction of the cell 10. There is an angle between the first radial direction and the second radial direction of the cell 10 in the same plane. Specifically, when there are two positive electrode connection portions 2011 and two negative electrode connection portions 2021, by placing the orthogonal projections of the two positive electrode connection portions 2011 in the height direction of the cell 10 onto the first radial direction of the cell 10 and placing the orthogonal projections of the two negative electrode connection portions 2021 in the height direction of the cell 10 onto the first radial direction of the cell 10, the charge distribution on the positive electrode busbar 201 can be made more uniform, which can improve the stability and reliability of the electrical connection between the positive electrode connection portion 2011 and the positive electrode tab 1011, and the charge distribution on the negative electrode busbar 202 can be made more uniform, which can improve the stability and reliability of the electrical connection between the negative electrode connection portion 2021 and the negative electrode tab 1021.

[0064] Furthermore, the first radial direction and the second radial direction of the cell 10 are at an angle to each other in the same plane, which can further ensure that the projections of the positive electrode connection 2011 and the negative electrode connection 2021 in the height direction of the cell 10 are at least partially offset from each other, and can further avoid the risk of performance degradation or failure of the battery 100 caused by the positive and negative high charge density regions being directly opposite each other.

[0065] Furthermore, the first radial direction and the second radial direction of the cell 10 are perpendicular to each other in the same plane. This arrangement not only ensures that the spacing between the orthogonal projections of the two positive electrode connection portions 2011 and the two negative electrode connection portions 2021 in the height direction of the cell 10 is uniform, but also maximizes the spacing between the orthogonal projections of the two positive electrode connection portions 2011 and the two negative electrode connection portions 2021 in the height direction of the cell 10. This can further avoid the high charge density regions of the positive and negative electrodes being directly opposite each other, thereby further reducing the risk of performance degradation or failure of the battery 100.

[0066] Combination Figure 4 and Figure 5 As shown, the positive electrode connection 2011 includes a first positive electrode welding section 2012 and a second positive electrode welding section 2013. The extension direction of the first positive electrode welding section 2012 and the extension direction of the second positive electrode welding section 2013 are at an angle α, and the value of α is in the range of 0°≤α≤95°; and / or the negative electrode connection 2021 includes a first negative electrode welding section 2022 and a second negative electrode welding section 2023. The extension direction of the first negative electrode welding section 2022 and the extension direction of the second negative electrode welding section 2023 are at an angle β, and the value of β is in the range of 0°≤β≤95°.

[0067] Specifically, given that there are two positive electrode connection portions 2011 and two negative electrode connection portions 2021, by ensuring that the included angle α defined between the extension direction of the first positive electrode welding section 2012 and the extension direction of the second positive electrode welding section 2013 is greater than or equal to 0 degrees and less than or equal to 95 degrees, and by ensuring that the included angle β defined between the first negative electrode welding section 2022 and the second negative electrode welding section 2023 is greater than or equal to 0 degrees and less than or equal to 95 degrees, it is possible to prevent α and β from being too large, thus ensuring the positive electrode connection portion 2011... The overlap area of ​​the negative electrode connection 2021 in the height direction of the cell 10 is too large, and the projection misalignment area of ​​the positive electrode connection 2011 and the negative electrode connection 2021 in the height direction of the cell 10 is small. On the other hand, it can prevent α and β from being too small. The uneven distribution of the first positive electrode welding segment 2012 and the second positive electrode welding segment 2013, and the uneven distribution of the first negative electrode welding segment 2022 and the second negative electrode welding segment 2023, result in uneven charge distribution on the positive electrode busbar 201 and the negative electrode busbar 202.

[0068] Combination Figure 6 , Figure 7 and Figure 8 As shown, there are three positive electrode connection portions 2011 and three negative electrode connection portions 2021. In the height direction of the cell 10, the orthographic projections of the three positive electrode connection portions 2011 and the three negative electrode connection portions 2021 are alternately spaced in the circumferential direction of the cell 10. Specifically, when there are three positive electrode connection portions 2011 and three negative electrode connection portions 2021, by alternately spaced the orthographic projections of the three positive electrode connection portions 2011 and the three negative electrode connection portions 2021 in the height direction of the cell 10 in the circumferential direction of the cell 10, the charge distribution on the positive electrode busbar 201 can be made more uniform, improving the stability and reliability of the electrical connection between the positive electrode connection portions 2011 and the positive electrode tab 1011. Similarly, the charge distribution on the negative electrode busbar 202 can be made more uniform, improving the stability and reliability of the electrical connection between the negative electrode connection portions 2021 and the negative electrode tab 1021.

[0069] Combination Figure 6 , Figure 7 and Figure 8 As shown, the positive electrode connection 2011 includes a first positive electrode welding section 2012 and a second positive electrode welding section 2013. The extension direction of the first positive electrode welding section 2012 and the extension direction of the second positive electrode welding section 2013 are at an angle α, and the value of α is in the range of 0°≤α≤65°; and / or the negative electrode connection 2021 includes a first negative electrode welding section 2022 and a second negative electrode welding section 2023. The extension direction of the first negative electrode welding section 2022 and the extension direction of the second negative electrode welding section 2023 are at an angle β, and the value of β is in the range of 0°≤β≤65°.

[0070] Specifically, given that there are three positive electrode connection portions 2011 and three negative electrode connection portions 2021, by ensuring that the included angle α defined between the extension direction of the first positive electrode welding segment 2012 and the extension direction of the second positive electrode welding segment 2013 is greater than or equal to 0 degrees and less than or equal to 65 degrees, and by ensuring that the included angle β defined between the first negative electrode welding segment 2022 and the second negative electrode welding segment 2023 is greater than or equal to 0 degrees and less than or equal to 65 degrees, it is possible to prevent α and β from being too large, thus ensuring the positive electrode connection portion 2011... The overlap area of ​​the negative electrode connection 2021 in the height direction of the cell 10 is too large, and the projection misalignment area of ​​the positive electrode connection 2011 and the negative electrode connection 2021 in the height direction of the cell 10 is small. On the other hand, it can prevent α and β from being too small. The uneven distribution of the first positive electrode welding segment 2012 and the second positive electrode welding segment 2013, and the uneven distribution of the first negative electrode welding segment 2022 and the second negative electrode welding segment 2023, result in uneven charge distribution on the positive electrode busbar 201 and the negative electrode busbar 202.

[0071] In some embodiments of this utility model, the number of positive electrode connection portions 2011 on the positive electrode busbar 201 and negative electrode connection portions 2021 on the negative electrode busbar 202 is not limited to two or three. More than three connection portions may be provided on the positive electrode busbar 201 and the negative electrode busbar 202. The number of positive electrode connection portions 2011 on the positive electrode busbar 201 and negative electrode connection portions 2021 on the negative electrode busbar 202 can be adjusted according to the specific capacity and specific requirements of the battery 100.

[0072] Combination Figure 4 and Figure 5 As shown, in the thickness direction of the positive electrode connector 201, the minimum distance between the orthographic projection of the positive electrode connection 2011 and the center of the outer contour of the orthographic projection of the positive electrode connector 201 is L1, and the value range of L1 is: L1≥3mm; and / or the minimum distance between the negative electrode connection 2021 and the center of the negative electrode connector 202 is L2, and the value range of L2 is: L2≥3mm.

[0073] Specifically, the battery cell 10 includes a positive electrode 101 and a negative electrode 102 stacked along a first direction. The positive electrode 101 has a positive tab 1011 at one end in the height direction of the battery cell 10, and the negative electrode 102 has a negative tab 1021 at the end in the height direction of the battery cell 10 away from the positive tab 1011. A separator is provided between adjacent positive electrode 101 and negative electrode 102, which can isolate the positive electrode 101 and negative electrode 102 and prevent short circuits caused by contact between the positive and negative electrodes. In the thickness direction of the positive electrode busbar 201, the centers of the positive electrode connection portion 2011 and the outer contour of the positive electrode busbar 201 are spaced apart, and the minimum distance between the center of the positive electrode connection portion 2011 and the outer contour of the positive electrode busbar 201 is greater than or equal to 3mm. This can prevent the welding electrical connection between the positive electrode connection portion 2011 and the positive electrode tab 1011 from damaging the separator in the middle of the cell 10, thereby improving the reliability and performance of the battery 100.

[0074] Similarly, in the thickness direction of the positive electrode busbar 201, the centers of the outer contours of the positive projection of the negative electrode connection 2021 and the positive projection of the negative electrode busbar 202 are spaced apart, and the minimum distance between the centers of the outer contours of the positive projection of the negative electrode connection 2021 and the positive projection of the negative electrode busbar 202 is greater than or equal to 3mm. This can prevent the welding electrical connection between the negative electrode connection 2021 and the negative electrode tab 1021 from damaging the separator in the middle of the cell 10, thereby improving the reliability and performance of the battery 100.

[0075] In the thickness direction of the positive electrode busbar 201, the minimum distance between the center of the outer contour of the positive electrode connection part 2021 and the positive electrode busbar 202, and the minimum distance between the center of the outer contour of the positive electrode connection part 2011 and the positive electrode busbar 201 can be adjusted according to the specific structure and specific requirements of the battery 100. For example, the minimum value requirement can be adjusted to 2mm, 4mm, etc.

[0076] Combination Figure 4 and Figure 5 As shown, a positive electrode positioning part 2014 is provided on the edge of the positive electrode busbar 201, and a negative electrode positioning part 2024 is provided on the edge of the negative electrode busbar 202. The negative electrode positioning part 2024 and the positive electrode positioning part 2014 are positioned and cooperated so that the positive electrode connection part 2011 and the negative electrode connection part 2021 are at least partially offset in the orthogonal projection in the height direction.

[0077] Specifically, by positioning the negative electrode positioning part 2024 and the positive electrode positioning part 2014 together, the orthogonal projections of the positive electrode connection part 2011 and the negative electrode connection part 2021 in the height direction can be at least partially offset according to a preset value. This not only facilitates the installation of the negative electrode busbar 202 and the positive electrode busbar 201 on the cell 10, but also improves the accuracy of the at least partial offset between the negative electrode connection part 2021 and the positive electrode connection part 2011, which can improve the performance of the battery 100 to a certain extent.

[0078] Combination Figure 9 As shown, in the height direction of the cell 10, the orthographic projection of the positive electrode positioning part 2014 and the orthographic projection of the negative electrode positioning part 2024 at least partially overlap. Specifically, when the positive electrode busbar 201 and the negative electrode busbar 202 are installed on both sides of the cell 10 in the height direction, the projections of the positive electrode positioning part 2014 on the positive electrode busbar 201 and the negative electrode positioning part 2024 on the negative electrode busbar 202 in the height direction of the cell 10 can overlap with each other, thus achieving the positioning and cooperation of the positive electrode positioning part 2014 and the negative electrode positioning part 2024. This facilitates the positioning and cooperation of the positive electrode positioning part 2014 and the negative electrode positioning part 2024, further reducing the assembly difficulty of the battery 100.

[0079] In some embodiments of this utility model, the positive electrode positioning part 2014 is a positive electrode positioning notch, and the negative electrode positioning part 2024 is a negative electrode positioning notch. The shape of the positive electrode positioning notch and the negative electrode positioning notch is not limited to triangle, circle and rectangle.

[0080] Furthermore, both the positive electrode positioning part 2014 and the negative electrode positioning part 2024 are provided with notches. When the casing of the battery 100 is sleeved on the outside of the cell 10, the positioning ribs on the inner wall of the casing of the battery 100 can simultaneously engage with the notches for positioning. That is, the positive electrode positioning notch and the negative electrode positioning notch can also form a positioning engagement with the casing of the battery 100, ensuring that the casing of the battery 100 is convenient and quick to install.

[0081] Combination Figures 4-9 As shown, in the height direction of the cell 10, the orthogonal projection of the negative electrode positioning part 2024 and the orthogonal projection of the negative electrode connection part 2021 are spaced apart; and / or the orthogonal projection of the positive electrode positioning part 2014 and the orthogonal projection of the positive electrode connection part 2011 are spaced apart.

[0082] Specifically, the negative electrode connection portion 2021 and the edge of the negative electrode busbar 202 can jointly define a negative electrode positioning area, and the positive electrode connection portion 2011 and the edge of the positive electrode busbar 201 can jointly define a positive electrode positioning area. In one embodiment of the present invention, by setting the orthographic projection of the negative electrode positioning portion 2024 and the orthographic projection of the negative electrode connection portion 2021 at intervals in the height direction of the cell 10, the positive electrode positioning portion 2014 is located in the positive electrode positioning area. After the positive electrode positioning portion 2014 and the negative electrode positioning portion 2024 are positioned and matched, at least part of the orthographic projections of the negative electrode connection portion 2021 and the positive electrode connection portion 2011 in the height direction of the cell 10 will be offset simultaneously.

[0083] In another embodiment of this utility model, by setting the orthographic projection of the positive electrode positioning part 2014 and the orthographic projection of the positive electrode connection part 2011 at intervals in the height direction of the cell 10, the negative electrode positioning part 2024 is located in the negative electrode positioning area. After the positive electrode positioning part 2014 and the negative electrode positioning part 2024 are positioned and matched, the orthographic projections of the negative electrode connection part 2021 and the positive electrode connection part 2011 in the height direction of the cell 10 will be at least partially offset.

[0084] This configuration not only facilitates the positioning and cooperation of the positive electrode positioning part 2014 and the negative electrode positioning part 2024, but also allows the positive electrode connection part 2011 and the negative electrode connection part 2021 to be at least partially offset after the positive electrode positioning part 2014 and the negative electrode positioning part 2024 are positioned and cooperated, thus directly reducing the assembly difficulty of the battery 100 without the need for other adjustment steps.

[0085] Combination Figure 1As shown, the battery cell 10 includes a positive electrode 101 and a negative electrode 102 stacked along a first direction. The positive electrode 101 has a positive electrode tab 1011 at one end in the height direction of the battery cell 10, and the negative electrode 102 has a negative electrode tab 1021 at the end in the height direction of the battery cell 10 away from the positive electrode tab 1011. The positive electrode 101 includes a positive electrode coating area 1012, and the negative electrode 102 includes a negative electrode coating area 1022. In the first direction, the orthographic projection of the positive electrode coating area 1012 is located within the orthographic projection of the negative electrode coating area 1022.

[0086] Specifically, by stacking positive electrode 101 and negative electrode 102 in a first direction and winding them in a second direction to form a battery cell 10, a separator is provided between two adjacent positive electrode 101 and negative electrode 102. The separator can prevent the positive electrode 101 and negative electrode 102 from contacting each other and causing short circuit failure. By making the orthogonal projection of the positive electrode coating area 1012 of the positive electrode 101 located within the orthogonal projection of the negative electrode coating area 1022 in the first direction, not only can the risk of failure due to contact between the positive electrode 101 and negative electrode 102 in the two sides of the height direction of the battery cell 10 after winding be reduced, but also the risk of failure due to contact between the positive electrode 101 and negative electrode 102 in the edge area of ​​the battery cell 10 in the second direction after winding be reduced, thereby further improving the stability and performance of the battery 100.

[0087] It should be noted that the negative electrode coating region 1022 is formed by coating an active material onto the negative electrode sheet 102. The main material of the active material on the negative electrode coating region 1022 includes, but is not limited to, graphite, hard carbon, and silicon carbide materials. The positive electrode coating region 1012 is formed by coating an active material onto the positive electrode sheet 101. The main material of the active material includes, but is not limited to, transition metal oxides, lithium iron phosphate, polyanionic compounds, and Prussian blue compounds.

[0088] Combination Figures 1-3 As shown, the positive electrode 101 and the negative electrode 102 are wound along the second direction to form a battery cell 10. One end of the positive electrode 101 in the second direction is set as the positive winding initial end 1014. The minimum distance between the positive electrode tab 1011 and the positive winding initial end 1014 along the second direction is greater than the minimum distance between the negative electrode tab 1021 and the positive winding initial end 1014 along the second direction. This setting can prevent the positive winding initial end 1014 and the negative electrode 102 from coming into contact with each other and causing failure. This can further improve the stability and performance of the battery 100.

[0089] It should be noted that the spacing between the positive electrode tab 1011 and the positive electrode winding initial end 1014, and the spacing between the negative electrode tab 1021 and the negative electrode winding initial end 1024, can prevent the injection hole 21 from being blocked after the positive electrode tab 1011 or the negative electrode tab 1021 is flattened.

[0090] Combination Figures 1-3 As shown, the total current-carrying area of ​​the negative electrode tab 1021 is greater than or equal to the total current-carrying area of ​​the positive electrode tab 1011. Specifically, it can be understood that the electronic conductivity of the negative electrode active material is less than that of the positive electrode active material. By making the total current-carrying area of ​​the negative electrode tab 1021 greater than or equal to the total current-carrying area of ​​the positive electrode tab 1011, the difference in electronic conductivity between the positive electrode 101 and the negative electrode 102 can be compensated, thereby making the current more stable.

[0091] In addition, by increasing the overcurrent area of ​​the negative electrode tab 1021, the current can be better distributed during the charging and discharging process of the battery 100, and the temperature of the battery 100 can be reduced, which can further improve the performance of the battery 100.

[0092] Combination Figures 1-3 As shown, before winding, there are multiple negative tabs 1021 and spaced apart along the second direction, and multiple positive tabs 1011 and spaced apart along the second direction. Before winding, the minimum distance between two adjacent positive tabs 1011 is L3 and the minimum distance between two adjacent negative tabs 1021 is L4 in the second direction. L3 and L4 satisfy the relationship: L3≥L4; and / or before winding, the maximum size of the positive tab 1011 is L5 and the maximum size of the negative tab 1021 is L6 in the second direction, and L5≤L6; and / or before winding, the maximum size of the positive tab 1011 is L7 and the maximum size of the negative tab 1021 is L8 in the height direction of the cell 10, and L7≥L8.

[0093] In some embodiments of this utility model, the positive electrode 1011 and the negative electrode 1021 can be parallelograms. After the positive electrode 101 and the negative electrode 102 are wound, the positive electrode 1011 and the negative electrode 1021 can be flattened, and then the positive electrode bus 201 is electrically connected to the positive electrode 1011, and the negative electrode bus 202 is electrically connected to the negative electrode 1021. The current-passing surface of the positive electrode 1011 is one side of the positive electrode 1011 in the first direction, and the current-passing surface of the negative electrode 1021 is one side of the negative electrode 1021 in the first direction. Therefore, the length and width of the current-passing surface of the positive electrode 1011 extend in the second direction of the battery cell 10 and the height direction of the battery cell 10, respectively, and the length and width of the current-passing surface of the negative electrode 1021 extend in the second direction of the wire and the height direction of the battery cell 10, respectively.

[0094] In some embodiments of this utility model, combined with Figures 1-3As shown, there are multiple negative tabs 1021 spaced apart along the second direction, and multiple positive tabs 1011 spaced apart along the second direction. Before winding, the minimum distance between two adjacent positive tabs 1011 in the second direction is L3, and the minimum distance between two adjacent negative tabs 1021 is L4. L3 and L4 satisfy the relationship: L3≥L4. On the one hand, this can make the spacing between two adjacent positive tabs 1011 and the spacing between two adjacent negative tabs 1021 different, which can prevent the positive and negative charges of the battery 100 from being directly opposite each other, causing the battery 100 to fail. On the other hand, it can make the spacing between two adjacent positive tabs 1011 larger. Under the premise that the length of the positive electrode sheet 101 in the second direction remains unchanged, the number of positive tabs 1011 is smaller. This can make the overall current-carrying area of ​​multiple positive tabs 1011 smaller and the overall current-carrying area of ​​multiple negative tabs 1021 larger.

[0095] In some embodiments of this utility model, combined with Figures 1-3 As shown, before winding, in the second direction, the maximum size of the positive electrode tab 1011 is L5, and the maximum size of the negative electrode tab 1021 is L6, where L5 ≤ L6. This ensures that the maximum size of the positive electrode tab 1011 in the second direction before winding is smaller than the maximum size of the negative electrode tab 1021 in the second direction before winding. This ensures that the size of the current-passing surface of the positive electrode 101 in the height direction of the cell 10 remains unchanged, and that the size of the current-passing surface of the negative electrode 102 in the height direction of the cell 10 remains unchanged, while also ensuring that the area of ​​the current-passing surface of the positive electrode 101 is smaller than the area of ​​the current-passing surface of the negative electrode 102.

[0096] In some embodiments of this utility model, before winding, the maximum size of the positive electrode tab 1011 in the second direction is L7, and the maximum size of the negative electrode tab 1021 is L8, where L7 ≥ L8. This allows the maximum size of the positive electrode tab 1011 in the height direction of the cell 10 before winding to be smaller than the maximum size of the negative electrode tab 1021 in the height direction of the cell 10 before winding. This ensures that the size of the flow surface of the positive electrode 101 remains unchanged in the second direction, and that the area of ​​the flow surface of the negative electrode 102 remains unchanged in the second direction, thereby making the area of ​​the flow surface of the positive electrode 101 smaller than the area of ​​the flow surface of the negative electrode 102.

[0097] Combination Figures 1-3 As shown, a positive electrode transition fillet is provided between the positive electrode tab 1011 and the positive electrode plate 101. The distance between the lower side of the positive electrode plate 101 and the center of the positive electrode transition fillet in the vertical direction is L9, where L9 > 0. This allows the lower edge of the positive electrode tab 1011 to be slightly lower than the upper edge of the positive electrode plate 101, which can improve the flattening yield of the positive electrode tab 1011 and improve the process capability of the flattening process of the positive electrode tab 1011.

[0098] Combination Figure 1 , Figure 2 and Figure 3 As shown, a negative electrode transition fillet is provided between the negative electrode tab 1021 and the negative electrode sheet 102. The distance between the lower side of the negative electrode sheet 102 and the center of the negative electrode transition fillet in the vertical direction is L10, where L10 > 0. This allows the lower edge of the negative electrode tab 1021 to be slightly lower than the upper edge of the negative electrode sheet 102, which can improve the flattening yield of the negative electrode tab 1021 and improve the process capability of the flattening process of the negative electrode tab 1021.

[0099] Combination Figure 1 , Figure 2 and Figure 3 As shown, the positive tab 1011 and / or the negative tab 1021 are at least one of a parallelogram, trapezoid, rhombus, and circle. Specifically, by making the positive tab 1011 and / or the negative tab 1021 at least one of a parallelogram, trapezoid, rhombus, and circle, not only can the current distribution on the positive tab 1011 and / or the negative tab 1021 be optimized, improving the charging and discharging efficiency of the battery 100, but it can also help avoid the problems of local overheating and stress concentration in the positive tab 1011 and / or the negative tab 1021.

[0100] Furthermore, the edges of the positive tab 1011 and the negative tab 1021 can be processed into rounded or chamfered structures. This not only prevents stress concentration in the positive tab 1011 and / or the negative tab 1021 and prevents breakage of the positive tab 1011 and / or the negative tab 1021, but also removes burrs and sharp edges from the battery 100, improves the safety of the battery 100, optimizes the edge design of the battery 100, optimizes the charge distribution on the positive tab 1011 and / or the negative tab 1021, and improves the performance of the battery 100.

[0101] In some embodiments of this utility model, the structural design of the battery 100 is applicable to both lithium-ion battery 100 and sodium-ion battery 100.

[0102] The battery 100 assembly according to this utility model mainly includes: the battery 100 and a circuit structure. The battery 100 is connected to the circuit structure, which can improve the stability and reliability of the battery 100 assembly.

[0103] The electrical equipment according to this utility model can mainly include: the battery 100 and / or the battery 100 assembly. Since the structure of the battery 100 is more reliable and has good working performance, applying any of the battery 100 and / or battery 100 assembly to the electrical equipment can not only reduce the failure risk of the edge of the multi-tab electrode cell 10 and the tabless region in the later stage of charging by differentiating the design of the positive tab 1011 and the negative tab 1021, but also avoid the risk of performance degradation or failure of the battery 100 caused by the high charge density areas of the positive and negative electrodes facing each other by the staggered design of the welding areas on the positive busbar 201 and the negative busbar 202. In addition, the structural design of the battery 100 is simple and feasible, without introducing additional processes. The structural design of the battery 100 can be introduced into the existing system to realize the application of the battery 100, and further, the performance and quality of the electrical equipment can be improved.

[0104] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0105] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0106] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery, characterized by, include: The battery cell (10) includes a positive tab (1011) and a negative tab (1021). A positive electrode busbar (201) is disposed on one side of the battery cell (10) in the height direction. The positive electrode busbar (201) includes a positive electrode connection part (2011), which is electrically connected to the positive electrode tab (1011). A negative electrode busbar (202) is disposed on the other side of the height direction of the battery cell (10). The negative electrode busbar (202) includes a negative electrode connection part (2021), which is electrically connected to the negative electrode tab (1021). In the height direction of the cell (10), the orthographic projection of the positive electrode connection (2011) and the orthographic projection of the negative electrode connection (2021) are at least partially offset.

2. The battery of claim 1, wherein, In the height direction of the cell (10), the orthographic projection of the positive electrode connection (2011) and the orthographic projection of the negative electrode connection (2021) are completely misaligned.

3. The battery of claim 1, wherein, The positive electrode busbar (201) includes a plurality of spaced-apart positive electrode connections (2011), and the negative electrode busbar (202) includes a plurality of spaced-apart negative electrode connections (2021). In the height direction of the battery cell (10), at least a portion of the orthographic projections of the positive electrode connections (2011) and the negative electrode connections (2021) are completely offset; and / or At least part of the orthographic projection of the negative electrode connection (2021) and the orthographic projection of the positive electrode connection (2011) are completely misaligned.

4. The battery of claim 3, wherein, The orthographic projections of at least a portion of the positive electrode connection portion (2011) and at least a portion of the negative electrode connection portion (2021) in the height direction of the cell (10) are alternately spaced along the circumference of the cell (10).

5. The battery of claim 4, wherein, There are two positive electrode connection portions (2011) and two negative electrode connection portions (2021). In the height direction of the cell (10), the orthographic projections of the two positive electrode connection portions (2011) are arranged opposite each other in the first radial direction of the cell (10), and the orthographic projections of the two negative electrode connection portions (2021) are arranged opposite each other in the second radial direction of the cell (10). There is an angle between the first radial direction and the second radial direction of the cell (10) in the same plane.

6. The battery of claim 5, wherein, The first radial direction and the second radial direction of the battery cell (10) are perpendicular to each other in the same plane.

7. The battery of claim 6, wherein, The positive electrode connection portion (2011) includes a first positive electrode welding section (2012) and a second positive electrode welding section (2013). The extension direction of the first positive electrode welding section (2012) and the extension direction of the second positive electrode welding section (2013) are at an angle α, where the value of α ranges from 0° to 95°. The negative electrode connection part (2021) includes a first negative electrode welding section (2022) and a second negative electrode welding section (2023). The extension direction of the first negative electrode welding section (2022) and the extension direction of the second negative electrode welding section have an angle β, and the value range of β is: 0°≤β≤95°.

8. The battery of claim 4, wherein, There are three positive electrode connection parts (2011) and three negative electrode connection parts (2021). In the height direction of the cell (10), the orthographic projections of the three positive electrode connection parts (2011) and the orthographic projections of the three negative electrode connection parts (2021) are alternately arranged in the circumferential direction of the cell (10).

9. The battery of claim 8, wherein, The positive electrode connection portion (2011) includes a first positive electrode welding section (2012) and a second positive electrode welding section (2013). The extension direction of the first positive electrode welding section (2012) and the extension direction of the second positive electrode welding section (2013) are at an angle α, where the value of α is in the range of 0°≤α≤65°; and / or The negative electrode connection part (2021) includes a first negative electrode welding section (2022) and a second negative electrode welding section (2023). The extension direction of the first negative electrode welding section (2022) and the extension direction of the second negative electrode welding section (2023) are at an angle β, and the value range of β is: 0°≤β≤65°.

10. The battery of claim 2, wherein, In the thickness direction of the positive electrode busbar (201), the minimum distance between the orthographic projection of the positive electrode connection portion (2011) and the center of the outer contour of the orthographic projection of the positive electrode busbar (201) is L1, and the value range of L1 is: L1≥3mm; and / or The minimum distance between the center of the negative electrode connection part (2021) and the center of the negative electrode busbar (202) is L2, and the value range of L2 is: L2≥3mm.

11. The battery of claim 1, wherein, The positive electrode busbar (201) is provided with a positive electrode positioning part (2014) on its edge, and the negative electrode busbar (202) is provided with a negative electrode positioning part (2024) on its edge. The negative electrode positioning part (2024) and the positive electrode positioning part (2014) are positioned and cooperated so that the positive electrode connection part (2011) and the negative electrode connection part (2021) are at least partially misaligned in the orthogonal projection in the height direction.

12. The battery of claim 11, wherein, In the height direction of the cell (10), the orthographic projection of the positive electrode positioning part (2014) and the orthographic projection of the negative electrode positioning part (2024) at least partially overlap.

13. The battery of claim 11, wherein, In the height direction of the battery cell (10), the orthogonal projection of the negative electrode positioning part (2024) and the orthogonal projection of the negative electrode connection part (2021) are spaced apart; and / or The orthographic projection of the positive electrode positioning part (2014) and the orthographic projection of the positive electrode connection part (2011) are spaced apart.

14. The battery of any one of claims 1-13, wherein, The battery cell (10) includes a positive electrode sheet (101) and a negative electrode sheet (102) stacked along a first direction. The positive electrode sheet (101) has a positive electrode tab (1011) at one end in the height direction of the battery cell (10), and the negative electrode sheet (102) has a negative electrode tab (1021) at one end in the height direction of the battery cell (10) away from the positive electrode tab. The positive electrode sheet (101) includes a positive electrode coating area, and the negative electrode sheet (102) includes a negative electrode coating area. In the first direction, the orthographic projection of the positive electrode coating area is located within the orthographic projection of the negative electrode coating area.

15. The battery of claim 14, wherein, The positive electrode (101) and the negative electrode (102) are wound along a second direction to form the battery cell (10). One end of the positive electrode (101) in the second direction is set as the initial end of the positive winding. The minimum distance between the positive electrode tab (1011) and the initial end of the positive winding (1014) along the second direction is greater than the minimum distance between the negative electrode tab (1021) and the initial end of the positive winding along the second direction.

16. The battery of claim 15, wherein, The total flow area of ​​the negative electrode (1021) is greater than or equal to the total flow area of ​​the positive electrode (1011).

17. The battery of claim 16, wherein, Before winding, in the second direction, the battery cell has multiple negative tabs (1021) spaced apart along the second direction, and multiple positive tabs (1011) spaced apart along the second direction. Before winding, in the second direction, the minimum distance between two adjacent positive tabs (1011) is L3, and the minimum distance between two adjacent negative tabs (1021) is L4. L6 and L7 satisfy the relationship: L3 ≥ L4; and / or Before winding, in the second direction, the maximum size of the positive tab (1011) of the battery cell is L5, and the maximum size of the negative tab (1021) is L6, where L5 ≤ L6; and / or Before winding, in the height direction of the battery cell (10), the maximum size of the positive tab (1011) is L7, and the maximum size of the negative tab (1021) is L8, where L7 ≥ L8.

18. A battery assembly comprising: The battery includes any one of claims 1-17, and a circuit structure, wherein the battery is electrically connected to the circuit structure.

19. An electrical device, comprising: Includes the battery according to any one of claims 1-17, and / or includes the battery assembly according to claim 18.

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