Battery monomer, battery and electric device

Abstract

The invention provides a battery monomer, a battery and a power utilization device. Each single battery comprises a first electrode assembly and a second electrode assembly which are stacked, and the first electrode assembly and the second electrode assembly are stacked in the thickness direction of the single battery; each of the first electrode assembly and the second electrode assembly comprises a first tab group and a second tab group, and the first tab group and the second tab group are located at the two opposite ends of the corresponding electrode assembly in the length direction of the single battery; the central axis of at least one of the first tab group and the second tab group is staggered with the central axis of the corresponding electrode assembly in the length direction; and the two first tab groups of the first electrode assembly and the second electrode assembly are arranged in a staggered manner in the thickness direction of the battery monomer. According to the battery monomer, the battery and the power utilization device provided by the invention, undesirable phenomena of pseudo soldering and solder skips in the welding process can be reduced.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and particularly to a battery cell, a battery and an electrical device. Background Art

[0002] With the development of new energy technologies, battery cells play an important role in fields such as electric vehicles, smart phones, wearable devices, and energy storage systems due to their advantages of small size, light weight, no memory effect, and long cycle life. With continuous technological progress and product upgrades, the requirements for the energy density and safety performance of battery cells are also getting higher and higher. A battery cell with a high energy density means more stacking layers or winding layers, and correspondingly, the number of tab layers is also increasing continuously. When the number of tab layers exceeds 60 layers, due to the limitations of existing ultrasonic welding technologies, it is easy to have poor welding phenomena such as virtual welding and missed welding in the welding of thicker tab layers, resulting in weak overcurrent capacity of the tabs, too high local temperature rise of the tabs, and large internal impedance, which affect the cycle life and safety performance of the battery. Summary of the Invention

[0003] Based on this, it is necessary to provide a battery cell, a battery and an electrical device that can reduce the poor welding phenomena such as virtual welding and missed welding during the welding process for the above problems.

[0004] A battery cell, the battery cell includes a first electrode assembly and a second electrode assembly stacked, and the first electrode assembly and the second electrode assembly are stacked along the thickness direction of the battery cell;

[0005] Both the first electrode assembly and the second electrode assembly include a first tab group and a second tab group. Along the length direction of the battery cell, the first tab group and the second tab group are located at opposite ends of the corresponding electrode assembly. In the same electrode assembly, the central axis of at least one of the first tab group and the second tab group is misaligned with the central axis of the length direction of the corresponding electrode assembly;

[0006] The two first tab groups of the first electrode assembly and the second electrode assembly are staggeredly arranged in the thickness direction of the battery cell.

[0007] In some embodiments, in the thickness direction of the battery cell, the orthographic projections of the two first tab groups of the first electrode assembly and the second electrode assembly do not overlap.

[0008] In some embodiments, in the width direction of the battery cell, the distance between the central axis of the first tab group of the first electrode assembly and the central axis of the length direction of the first electrode assembly is deltA1, and the deltA1 is less than or equal to (0.5*W - 0.5*W 第一极耳组), where W is the width of the electrode assembly, and W 第一极耳组 is the maximum width of the first tab group;

[0009] The central axis of the first tab group of the second electrode assembly overlaps with the central axis of the length direction of the second electrode assembly.

[0010] In some embodiments, the deltaA1 is less than or equal to (0.25 * W).

[0011] In some embodiments, in the width direction of the battery cell, the distance between the central axis of the first tab group of the first electrode assembly and the central axis of the length direction of the first electrode assembly is deltaA1, and the distance between the central axis of the first tab group of the second electrode assembly and the central axis of the length direction of the second electrode assembly is deltaA2. The deltaA1 is less than or equal to (0.5 * W - 0.5 * W 第一极耳组 ), and the deltaA2 is less than or equal to (0.5 * W - 0.5 * W 第一极耳组 ), where W is the width of the electrode assembly, and W 第一极耳组 is the maximum width of the first tab group.

[0012] In some embodiments, in the width direction of the battery cell, the central axes of the first tab groups of the first electrode assembly and the second electrode assembly are respectively located on both sides of the central axis of the length direction of the battery cell.

[0013] In some embodiments, the first tab group of the first electrode assembly and the first tab group of the second electrode assembly are centrosymmetrically distributed about the central axis of the length direction of the battery cell.

[0014] In some embodiments, in the width direction of the battery cell, the distance between the central axes of the first tab groups of the first electrode assembly and the second electrode assembly is deltaA3. The deltaA3 is less than or equal to (W - W 第一极耳组 ) and greater than or equal to W 第一极耳组 , preferably, the deltaA3 is less than or equal to 0.5W.

[0015] A battery includes the battery cell as described in any one of the above embodiments.

[0016] An electrical device includes the battery as described in the above embodiments, and the battery is used to provide electrical energy for the electrical device.

[0017] Compared with the prior art, the present application has the following beneficial effects:

[0018] In the above battery cell, battery, and electrical device, by designing the central axis of at least one of the first tab group and the second tab group in the same electrode assembly to be misaligned with the central axis of the corresponding electrode assembly in the length direction, and the two first tab groups of the first electrode assembly and the second electrode assembly are arranged staggeredly in the thickness direction of the battery cell, such that there is a non-overlapping part in the orthographic projection of the two first tab groups of the first electrode assembly and the second electrode assembly in the thickness direction of the battery cell. In this case, welding the non-overlapping part of the orthographic projection of the two first tab groups of the first electrode assembly and the second electrode assembly in the thickness direction of the electrode assembly to the first pole column or the first adapter plate of the battery cell will not result in poor welding such as virtual welding or missed welding due to an overly thick tab layer. Moreover, the welding difficulty is also reduced. In this way, the current-carrying capacity of the first tab group can be ensured, the local temperature rise of the first tab group will not be too high, the internal impedance is small, and the battery cell has a long cycle life and safety performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic structural diagram of the battery cell in the core-unfolding stage when the distance between the central axis of the first tab group of the first electrode assembly and the central axis of the first electrode assembly in the length direction is ΔA1, and the central axis of the first tab group of the second electrode assembly coincides with the central axis of the second electrode assembly in the length direction in an embodiment of the present application;

[0020] Figure 2 Schematic structural diagram of the first electrode assembly in another embodiment of the present application;

[0021] Figure 3 Schematic structural diagram of the battery cell in the core-unfolding stage when the distance between the central axis of the first tab group of the first electrode assembly and the central axis of the first electrode assembly in the length direction is ΔA1, and the distance between the central axis of the first tab group of the second electrode assembly and the central axis of the second electrode assembly in the length direction is ΔA2 in another embodiment of the present application;

[0022] Figure 4 is Figure 3 Schematic structural diagram of the battery cell shown in the core-folding stage;

[0023] Figure 5 Schematic structural diagram of the second electrode assembly in yet another embodiment of the present application;

[0024] Figure 6 Schematic structural diagram of the battery cell in the core-unfolding stage when the distance between the central axis of the first tab group of the first electrode assembly and the central axis of the first electrode assembly in the length direction is ΔA1, and the distance between the central axis of the first tab group of the second electrode assembly and the central axis of the second electrode assembly in the length direction is ΔA2 in yet another embodiment of the present application;

[0025] Figure 7 is Figure 6 a schematic structural view of the battery cell in the core - combining stage as shown;

[0026] Figure 8 is Figure 1 or Figure 3 or Figure 6 a schematic structural view of the cooperation before welding between the two sets of first tab groups of the first electrode assembly and the second electrode assembly in the battery cell as shown;

[0027] Reference numerals in the drawings:

[0028] 1. Battery cell;

[0029] 10. Electrode assembly; 20. First end cap; 30. Second end cap; 40. Housing; 50. First adapter tab; 60. Second adapter tab;

[0030] 10a. First electrode assembly; 10b. Second electrode assembly; 11. First tab group; 111. First tab side edge; 112. Second tab side edge; 12. Second tab group; 13. Body; 131. First body side edge; 132. Second body side edge;

[0031] X. Length direction of the battery cell; Y. Width direction of the battery cell; Z. Thickness direction of the battery cell. Detailed implementation manners

[0032] To make the above - mentioned objects, features, and advantages of the present application more obvious and understandable, the following will describe the detailed implementation manners of the present application with reference to the accompanying drawings. Many specific details are set forth in the following description to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein. Those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0033] In the description of the present application, it should be understood that the orientation or positional relationships indicated by 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. are based on the orientation or positional relationships shown in the accompanying drawings. These are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present application.

[0034] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of this application, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0035] In this application, unless otherwise clearly defined and limited, terms such as "installed", "connected", "joined", "fixed", etc. shall be construed in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0036] In this application, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "below" and "beneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0037] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it may be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation.

[0038] With the development of new energy technologies, battery cells play an important role in fields such as electric vehicles, smartphones, wearable devices, and energy storage systems due to their advantages of small size, light weight, no memory effect, and long cycle life. With the continuous progress of technology and the continuous upgrading of products, the requirements for the energy density and safety performance of battery cells are also getting higher and higher. A battery cell with high energy density means more stacking layers or winding layers, and correspondingly, the number of tab layers is also increasing continuously. When the number of tab layers exceeds 60 layers, limited by the existing ultrasonic welding technology, it is easy to have poor welding phenomena such as virtual welding and missed welding in the welding of thicker tab layers, resulting in weak overcurrent capacity of the tabs, too high local temperature rise of the tabs, and large internal impedance, which affects the cycle life and safety performance of the battery.

[0039] Please refer to Figures 1 to 6 , in order to alleviate the above problems, this application designs a battery cell 1. The battery cell 1 includes a first electrode assembly 10a and a second electrode assembly 10b that are stacked. The first electrode assembly 10a and the second electrode assembly 10b are stacked along the thickness direction Z of the battery cell 1. Both the first electrode assembly 10a and the second electrode assembly 10b include a first tab group 11 and a second tab group 12. Along the length direction X of the battery cell 1, the first tab group 11 and the second tab group 12 are located at opposite ends of the corresponding electrode assembly 10. In the same electrode assembly, the central axis of at least one of the first tab group 11 and the second tab group 12 is misaligned with the central axis of the length direction of the corresponding electrode assembly 10. The two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b are staggered in the thickness direction Z of the battery cell 1.

[0040] The first tab group 11 is either a positive tab group or a negative tab group, and the second tab group 12 is the other of the positive tab group and the negative tab group. Among them, one layer of positive electrode sheet, one layer of separator, one layer of negative electrode sheet, and one layer of separator are alternately formed into a unit, and multiple such units are stacked to form the electrode assembly 10. Or, it can also be formed by winding one layer of positive electrode sheet, one layer of separator, one layer of negative electrode sheet, and one layer of separator alternately and stacked, which can be specifically set according to requirements. Each positive electrode sheet is led out unilaterally and die-cut to form a positive tab, and each negative electrode sheet is led out unilaterally and die-cut to form a negative tab. In the electrode assembly 10, all the stacked positive tabs are welded to form a positive tab group, and all the stacked negative tabs are welded to form a negative tab group. The electrode assembly 10 further includes a main body 13, and the main body 13 is jointly constructed by the parts where neither the positive electrode sheet nor the negative electrode sheet is led out and the separator. The positive tab group and the negative tab group are arranged at both ends of the main body 13.

[0041] In the battery cell 1, the first electrode assembly 10a and the second electrode assembly 10b are set in a supporting manner to form an electrode assembly group. In the battery cell 1, the electrode assembly group can be one group or multiple groups, which can be specifically set according to requirements.

[0042] The central axis of the first tab group 11 is the central axis of the first tab group 11 set along the length direction X of the battery cell 1. The central axis of the second tab group 12 is the central axis of the second tab group 12 set along the length direction X of the battery cell 1.

[0043] In the same electrode assembly, the central axis of at least one of the first tab group 11 and the second tab group 12 is misaligned with the central axis of the corresponding electrode assembly 10 in the length direction, such as Figure 1 taking the first electrode assembly 10a as an example, the central axes of the first tab group 11 and the second tab group 12 of the first electrode assembly 10a (the central axis of the first tab group 11 of the first electrode assembly 10a is as shown by L3 in Figure 1 are both misaligned with the central axis of the first electrode assembly 10a in the length direction (as shown by L1 in Figure 1 ). At the same time, the central axis of the first tab group 11 of the second electrode assembly 10b (as shown by L4 in Figure 1 ) overlaps with the central axis of the second electrode assembly 10b in the length direction (as shown by L2 in Figure 1 ), but the central axis of the second tab group 12 of the second electrode assembly 10b is misaligned with the central axis of the second electrode assembly 10b in the length direction.

[0044] Another example, taking Figure 3 as an example, the central axis of the first tab group 11 of the first electrode assembly 10a (as shown by L3 in Figure 3 ) is misaligned with the central axis of the first electrode assembly 10a in the length direction (as shown by L1 in Figure 3 ), the central axis of the second tab group 12 of the first electrode assembly 10a overlaps with the central axis of the first electrode assembly 10a in the length direction. At the same time, the central axis of the first tab group 11 of the second electrode assembly 10b (as shown by L4 in Figure 3 ) is misaligned with the central axis of the second electrode assembly 10b in the length direction (as shown by L2 in Figure 3 ), but the central axis of the second tab group 12 of the second electrode assembly 10b overlaps with the central axis of the second electrode assembly 10b in the length direction.

[0045] Another example, taking Figure 6 as an example, the central axes of both the first tab group 11 and the second tab group 12 of the first electrode assembly 10a are misaligned with the central axis of the first electrode assembly 10a in the length direction (the central axis of the first tab group 11 of the first electrode assembly 10a is as shown by L3 in Figure 6 , and the central axis of the first electrode assembly 10a in the length direction is as shown by L1 in Figure 6as shown by L1 in the figure, and the central axes of the first tab group 11 and the second tab group 12 of the second electrode assembly 10b are offset from the central axis of the second electrode assembly 10b in the length direction (the central axis of the first tab group 11 of the second electrode assembly 10b is as shown by Figure 6 L4 in the figure, and the central axis of the second electrode assembly 10b in the length direction is as shown by Figure 6 L2 in the figure).

[0046] In this application, by designing that in the same electrode assembly, the central axis of at least one of the first tab group 11 and the second tab group 12 is offset from the central axis of the corresponding electrode assembly 10 in the length direction, and the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b are staggered in the thickness direction Z of the battery cell 1, so that there is a non-overlapping part in the positive projection of the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b in the thickness direction Z of the battery cell 1. In this case, the non-overlapping part of the positive projection of the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b in the thickness direction of the electrode assembly 10 is welded to the first pole column or the first adapter piece 50 of the battery cell 1, so that it is not easy to occur welding defects such as virtual welding and missed welding due to the excessive thickness of the tab layer. Moreover, the welding difficulty is also reduced. In this way, the current-carrying capacity of the first tab group 11 can be guaranteed, the local temperature rise of the first tab group 11 is not too high, the internal impedance is small, and the battery cell 1 has a long cycle life and safety performance.

[0047] Specifically, when the battery cell 1 has the first pole column and the second pole column, but does not have the first adapter piece 50 and the second adapter piece 60, the first tab group 11 is welded to the first pole column, and the second tab group 12 is welded to the second pole column; when the battery cell 1 has the first pole column, the second pole column, the first adapter piece 50 and the second adapter piece 60, the first adapter piece 50 is welded to the first tab group 11 and the first pole column, and the second adapter piece 60 is welded to the second tab group 12 and the second pole column.

[0048] When the first tab group 11 is a positive tab group and the second tab group 12 is a negative tab group, the first pole column is a positive pole column, the second pole column is a negative pole column, the first adapter piece 50 is a positive adapter piece, and the second adapter piece 60 is a negative adapter piece. When the first tab group 11 is a negative tab group and the second tab group 12 is a positive tab group, the first pole column is a negative pole column, the second pole column is a positive pole column, the first adapter piece 50 is a negative adapter piece, and the second adapter piece 60 is a positive adapter piece.

[0049] In some embodiments, in the thickness direction Z of the battery cell 1, the orthographic projections of the two sets of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b do not overlap, that is, there is no intersecting part in the orthographic projections of the two sets of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b.

[0050] In this way, when welding the non-overlapping parts of the orthographic projections of the two sets of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b in the thickness direction of the electrode assembly 10 to the first pole column or the first adapter plate 50 of the battery cell 1, the welding area is large, the welding is firm, and the possibility of poor phenomena such as virtual welding and missed welding is low.

[0051] Please refer to Figure 1 , in some embodiments, in the width direction Y of the battery cell 1, the central axis of the first tab group 11 of the first electrode assembly 10a (as shown by L3 in Figure 1 ) and the central axis of the first electrode assembly 10a in the length direction (as shown by L1 in Figure 1 ) have a spacing of deltA1, and deltA1 is less than or equal to 0.5*W - 0.5*W 第一极耳组 , where W is the width of the electrode assembly 10, and W 第一极耳组 is the maximum width of the first tab group 11; the central axis of the first tab group 11 of the second electrode assembly 10b (as shown by L4 in Figure 1 ) overlaps with the central axis of the second electrode assembly 10b in the length direction (as shown by L2 in Figure 1 ). That is, in this embodiment, the central axis of the first tab group 11 of the first electrode assembly 10a is offset from the central axis of the first electrode assembly 10a in the length direction, while the central axis of the first tab group 11 of the second electrode assembly 10b overlaps with the central axis of the second electrode assembly 10b in the length direction, so as to realize the staggered arrangement of the two sets of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b.

[0052] In this embodiment, the central axis of the second tab group 12 of the first electrode assembly 10a may be offset from the central axis of the first electrode assembly 10a in the length direction (at this time, the central axes of the first tab group 11 and the second tab group 12 of the first electrode assembly 10a may be on the same side or opposite sides of the central axis of the first electrode assembly 10a in the length direction) or overlap, and the central axis of the second tab group 12 of the second electrode assembly 10b is offset from the central axis of the second electrode assembly 10b in the length direction.

[0053] Specifically, the main body 13 of the electrode assembly 10 has a first main body side edge 131 and a second main body side edge 132 that are oppositely arranged in the width direction Y of the battery cell 1, and the spacing between the first main body side edge 131 and the second main body side edge 132 is W.

[0054] When the central axis of the first tab group 11 of the first electrode assembly 10a is misaligned with the central axis in the length direction of the first electrode assembly 10a, and the central axis of the first tab group 11 of the second electrode assembly 10b overlaps with the central axis in the length direction of the second electrode assembly 10b, the central axis of the first tab group 11 of the first electrode assembly 10a is close to the first main body side edge 131 of the first electrode assembly 10a.

[0055] In this embodiment, the first tab group 11 has a first surface facing the corresponding main body 13. The first surface of the first tab group 11 has a first tab side edge 111 and a second tab side edge 112 that are oppositely arranged in the width direction Y of the battery cell 1. The distance between the first tab side edge 111 and the second tab side edge 112 is W. 第一极耳组 。

[0056] In the first electrode assembly 10a, the first tab side edge 111 is farther from the central axis in the length direction of the first electrode assembly 10a than the second tab side edge 12, and the first tab side edge 111 is closer to the first main body side edge 131 than the second tab side edge 12. In the second electrode assembly 10b, the distances from the first tab side edge 111 and the second tab side edge 12 to the central axis in the length direction of the second electrode assembly 10b are equal, and the first tab side edge 111 is closer to the first main body side edge 131 than the second tab side edge 12.

[0057] When deltA1 is equal to 0.5*W - 0.5*W 第一极耳组 the distance between the central axis of the first tab group 11 of the first electrode assembly 10a and the central axis in the length direction of the first electrode assembly 10a is the largest. At this time, the first tab side edge 111 of the first tab group 11 in the first electrode assembly 10a coincides with the first main body side edge 131 of the first electrode assembly 10a, and the second tab side edge 112 of the first tab group 11 in the first electrode assembly 10a is located between the first main body side edge 131 of the first electrode assembly 10a and the central axis in the length direction of the first electrode assembly 10a.

[0058] When deltA1 is less than (0.5*W - 0.5*W 第一极耳组 ) the first tab side edge 111 of the first tab group 11 in the first electrode assembly 10a is located between the first main body side edge 131 of the first electrode assembly 10a and the central axis in the length direction of the first electrode assembly 10a, and the second tab side edge 112 of the first tab group 11 in the first electrode assembly 10a is located between the first main body side edge 131 of the first electrode assembly 10a and the central axis in the length direction of the first electrode assembly 10a, or is located between the central axis in the length direction of the first electrode assembly 10a and the second main body side edge 132 of the first electrode assembly 10a.

[0059] In this embodiment, by designing the distance between the central axis of the first tab group 11 of the first electrode assembly 10a and the central axis of the first electrode assembly 10a in the length direction to be deltA1, deltA1 is less than or equal to (0.5*W - 0.5*W 第一极耳组 ), where W is the width of the electrode assembly, and W 第一极耳组 is the maximum width of the first tab group 11; the central axis of the first tab group 11 of the second electrode assembly 10b coincides with the central axis of the second electrode assembly 10b in the length direction. On the premise that the two groups of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b can be staggered in the thickness direction Z of the battery cell to reduce the occurrence of defective phenomena such as virtual soldering and missed soldering during the welding process, the compactness of the layout of the two groups of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b can also be improved. In this way, the first pole column or the first adapter plate 50 welded to the two groups of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b can also be designed with a smaller size in the width direction Y of the battery cell 1, thereby facilitating the reduction of the manufacturing cost of the battery cell 1 and also facilitating the layout of other components in the width direction Y of the battery cell 1.

[0060] Furthermore, in some embodiments, deltA1 is less than or equal to (0.25*W). This design enables the first tab group 11 of the first electrode assembly 10a to be close to the central axis of the first electrode assembly 10a in the width direction Y of the battery cell 1. In this case, contact between the tab group 11 and the housing 40 of the battery cell 1 can be avoided, improving the safety of the battery cell 1 during use. In addition, under this design, the size of the first pole column or the first adapter plate 50 designed in the width direction of the battery cell 1 is further reduced, thereby further reducing the manufacturing cost of the battery cell 1, reducing the overcurrent length, reducing the internal resistance, and also facilitating the layout of other components in the width direction Y of the battery cell 1.

[0061] Please refer to Figures 2 to 7 simultaneously. In some embodiments, in the width direction Y of the battery cell 1, the distance between the central axis of the first tab group 11 of the first electrode assembly 10a and the central axis of the first electrode assembly 10a in the length direction is deltA1, and the distance between the central axis of the first tab group 11 of the second electrode assembly 10b and the central axis of the second electrode assembly 10b in the length direction is deltA2. deltA1 is less than or equal to (0.5*W - 0.5*W 第一极耳组 ), and deltA2 is less than or equal to (0.5*W - 0.5*W 第一极耳组 ), where W is the width of the electrode assembly 10, and W 第一极耳组is the maximum width of the first tab group 11. That is, in this embodiment, the central axis of the first tab group 11 of the first electrode assembly 10a is misaligned with the central axis of the first electrode assembly 10a in the length direction, and the central axis of the first tab group 11 of the second electrode assembly 10b is also misaligned with the central axis of the second electrode assembly 10b in the length direction, so as to realize the staggered arrangement of the two groups of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b.

[0062] In this embodiment, the central axis of the second tab group 12 of the first electrode assembly 10a may be misaligned with the central axis of the first electrode assembly 10a in the length direction (at this time, the central axes of the first tab group 11 and the second tab group 12 of the first electrode assembly 10a may be on the same side or opposite sides of the central axis of the first electrode assembly 10a in the length direction) or overlap, and the central axis of the second tab group 12 of the second electrode assembly 10b is misaligned with the central axis of the second electrode assembly 10b in the length direction (at this time, the central axes of the first tab group 11 and the second tab group 12 of the second electrode assembly 10b may be on the same side or opposite sides of the central axis of the second electrode assembly 10b in the length direction) or overlap.

[0063] In addition, in this embodiment, in the width direction Y of the battery cell 1, the central axes of the two groups of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b may be on the same side or opposite sides of the central axis of the battery cell 1 in the length direction X (such as Figure 4 and Figure 7 shown by L5). For the convenience of description, the following embodiments will be described by taking the central axes of the two groups of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b being on the opposite sides of the central axis of the battery cell 1 in the length direction X as an example.

[0064] Specifically, the central axis of the battery cell 1 in the length direction X is the central axis of the battery cell 1, and there is only one in the battery cell 1. The central axis of the first electrode assembly 10a in the length direction and the central axis of the second electrode assembly 10b in the length direction X are both the central axes of the electrode assemblies along their own length directions (consistent with the length direction X of the battery cell 1). Each electrode assembly has its own corresponding central axis along its own length direction, and the electrode assemblies at different positions in the thickness direction of the battery cell 1 have different central axes along their own length directions.

[0065] In this embodiment, for the convenience of description, the following embodiments will be described by taking the central axes of the two groups of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b being on the opposite sides of the central axis of the battery cell 1 in the length direction X as an example.

[0066] Moreover, in this embodiment, in the first electrode assembly 10a, the first tab side edge 111 is farther from the central axis of the length direction of the first electrode assembly 10a than the second tab side edge 12, and the first tab side edge 111 is closer to the first main body side edge 131 than the second tab side edge 12. In the second electrode assembly 10b, the first tab side edge 111 is farther from the central axis of the length direction of the second electrode assembly 10b than the second tab side edge 12, and the first tab side edge 111 is closer to the second main body side edge 132 than the second tab side edge 12.

[0067] When deltA1 and deltA2 are equal to 0.5*W - 0.5*W 第一极耳组 At this time, the distance between the central axes of the first tab group 11 of the first electrode assembly 10a and the second tab group 12 of the second electrode assembly 10b is the largest. At this time, the first tab side edge 111 of the first tab group 11 in the first electrode assembly 10a coincides with the first main body side edge 131 of the first electrode assembly 10a, and the first tab side edge 111 of the first tab group 11 in the second electrode assembly 10b coincides with the second main body side edge 132 of the second electrode assembly 10b.

[0068] When both deltA1 and deltA2 are less than (0.5*W - 0.5*W 第一极耳组 )), the first tab side edge 111 of the first tab group 11 in the first electrode assembly 10a is located between the first main body side edge 131 of the first electrode assembly 10a and the central axis of the length direction of the first electrode assembly 10a, and the first tab side edge 111 of the first tab group 11 in the second electrode assembly 10b is located between the second main body side edge 132 of the second electrode assembly 10b and the central axis of the length direction of the second electrode assembly 10b.

[0069] In this embodiment, by designing deltA1 less than or equal to (0.5*W - 0.5*W 第一极耳组 ), and deltA2 less than or equal to (0.5*W - 0.5*W 第一极耳组 ), the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b can be flexibly distributed in the width direction of the battery cell 1 according to the structure of the battery cell 1. On the premise of being able to satisfy the staggered arrangement of the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b to reduce the bad phenomena of virtual soldering and missed soldering during the welding process, the layout flexibility of the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b can also be improved.

[0070] Further, both deltA1 and deltA2 are less than or equal to (0.25*W). This design enables both sets of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b to be close to the central axis of the corresponding electrode assembly 10 in the length direction. In this case, contact between both sets of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b and the housing 40 of the battery cell 1 can be avoided, enhancing the safety of the battery cell 1 during use.

[0071] Please refer to Figures 3 to 7 , in some embodiments, in the width direction Y of the battery cell 1, the central axes of the first tab group 11 of the first electrode assembly 10a and the central axis of the first tab group 11 of the second electrode assembly 10b are respectively located on both sides of the central axis of the battery cell 1 in the length direction X.

[0072] In this way, there is a larger space for the first tab group 11 of the first electrode assembly 10a and the first tab group 11 of the second electrode assembly 10b to be staggeredly arranged in the width direction Y of the battery cell 1, enabling a greater degree of staggering between the first tab group 11 of the first electrode assembly 10a and the first tab group 11 of the second electrode assembly 10b. Furthermore, the overlapping portion of the first tab group 11 of the first electrode assembly 10a and the first tab group 11 of the second electrode assembly 10b projected in the thickness direction of the battery cell 1 is less, thereby further reducing the possibility of layer-by-layer welding of the staggered first tab groups 11 during welding and enhancing the welding effect.

[0073] In some embodiments, the first tab group 11 of the first electrode assembly 10a and the first tab group 11 of the second electrode assembly 10b are centrosymmetrically distributed with respect to the central axis of the battery cell 1 in the length direction X.

[0074] In this way, both sets of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b are evenly distributed on both sides of the central axis of the battery cell 1 in the length direction X with the central axis of the battery cell 1 in the length direction X as the boundary, and are both welded to one of the first pole and the first adapter piece 50, thereby facilitating the improvement of the uniformity and reliability of welding.

[0075] Please refer to Figure 3 and Figure 6 , in some embodiments, in the width direction Y of the battery cell 1, the central axis of the first tab group 11 of the first electrode assembly 10a (such as Figure 3 and Figure 6 shown as L3) and the central axis of the first tab group 11 of the second electrode assembly 10b (such as Figure 3 and Figure 6 shown as L4) have a spacing of deltA3, and deltA3 is less than or equal to (W - W 第一极耳组 ) and greater than or equal to W 第一极耳组, preferably, deltA3 is less than or equal to 0.5W.

[0076] deltA3 equals (W - W 第一极耳组 ), the first tab group 11 of the first electrode assembly 10a and the first tab group 11 of the second electrode assembly 10b are spaced apart in the width direction Y of the battery cell 1. At this time, the first tab side edge 111 of the first electrode assembly 10a coincides with the first main body side edge 131 of the first electrode assembly 10a, and the first tab side edge 111 of the second electrode assembly 10b coincides with the second main body side edge 132 of the second electrode assembly 10b.

[0077] deltA3 equals W 第一极耳组 , the first tab group 11 of the first electrode assembly 10a and the first tab group 11 of the second electrode assembly 10b are set with zero spacing in the width direction Y of the battery cell 1. At this time, the second tab side edge 12 of the first electrode assembly 10a contacts the central axis in the length direction of the first electrode assembly 10a, and the second tab side edge 12 of the second electrode assembly 10b contacts the central axis in the length direction of the second electrode assembly 10b.

[0078] When deltA3 equals 0.5W, the first tab group 11 of the first electrode assembly 10a and the first tab group 11 of the second electrode assembly 10b are spaced apart in the width direction Y of the battery cell 1. At this time, the first tab group 11 of the first electrode assembly 10a is located between the first main body side edge 131 of the first electrode assembly 10a and the central axis in the length direction of the first electrode assembly 10a, and the first tab group 11 of the second electrode assembly 10b is located between the second main body side edge 132 of the second electrode assembly 10b and the central axis in the length direction of the second electrode assembly 10b.

[0079] In this embodiment, deltA3 is less than or equal to (W - W 第一极耳组 ) and greater than or equal to W 第一极耳组When it is possible to ensure that the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b are arranged in a staggered manner, so as to reduce the possibility of poor soldering and missed soldering during welding and improve the welding effect, it also enables the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10 to have a large layout space in the width direction of the battery cell, and can be flexibly arranged according to the structure of the battery cell 1. When deltA3 is less than or equal to 0.5W, the distance between the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b is small. In this way, the size designed in the width direction Y of the battery cell 1 for the first pole column or the first adapter piece 50 welded to the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b can also be reduced, thereby further reducing the manufacturing cost of the battery cell 1 and facilitating the layout of other components in the width direction Y of the battery cell 1.

[0080] In some embodiments, in the case of high-current fast charging, such as when the charging current rate exceeds 2C, in the thickness direction Z of the battery cell 1, the orthographic projections of the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b do not overlap at all, that is, there is no intersecting part in the orthographic projections of the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b; for this stacked electrode assembly with a completely staggered design, in the width direction Y of the battery cell 1, the center distance between the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b is D full , where the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b are exactly the same.

[0081] D full is between its maximum value Dfull_max and minimum value Dfull_min.

[0082] The minimum value Dfull_min is W 第一极耳组 +S, where W 第一极耳组 is the maximum width of the tab group 11, and S is the safety distance of the welding heat affected zone. For example, for laser welding, it takes 1 - 2mm.

[0083] The maximum value Dfull_max is related to three factors: the covering ability of the first adapter piece 50, the current path uniformity, and the mechanical strength and vibration reliability.

[0084] 1. Dfull_max is limited by the width (C W ) of the first adapter piece 50, and it is necessary to ensure that the first adapter piece 50 can completely cover the welding areas of the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b; the width (C W)That is the dimension of the first connecting piece 50 in the width direction Y of the battery cell 1.

[0085] Dfull_ max1 ≤C W -W 第一极耳组 -2Sedge, where, C W : The width of the first connecting piece 50, for example, 15 mm; W 第一极耳组 : The maximum width of the first tab group 11; Sedge: The edge safety margin of the first connecting piece 50 to prevent poor edge contact, usually taken as 1 mm to 2 mm.

[0086] 2. Current path uniformity, excessive misalignment will cause the current path to extend, increasing resistance and local heating.

[0087] D full_max2 ≤(ΔR allow ·A cu ) / (ρ·L path )

[0088] ΔR allow : The allowable increased resistance, for example, not exceeding 5% of the total internal resistance;

[0089] A cu : The cross-sectional area of the first connecting piece 50 (the thickness of the first connecting piece 50 × the width of the first connecting piece 50);

[0090] ρ: The resistivity of the material of the first connecting piece 50;

[0091] L path : The additional current path length caused by misalignment, which is linearly related to D full_max2 For example,

[0092] Take K path ·D full_max2 For example, the coefficient K path ≈1.2.

[0093] Mechanical strength and vibration reliability, too large misalignment spacing will reduce the structural stiffness of the first connecting piece 50, and the anti-vibration fatigue requirements need to be met;

[0094]

[0095] E: The elastic modulus of the material of the first connecting piece 50, for example: for copper it is 120 GPa;

[0096] I: The moment of inertia of the cross-section of the first connecting piece 50;

[0097] F: The vibration load, for example, the typical value F = 50 N;

[0098] L: The cantilever length, approximately D full_max3.

[0099] Considering the coverage capability of the first adapter 50, the uniformity of the current path, the mechanical strength and the vibration reliability, the center distance D full The maximum value D full _max takes the minimum value of the above constraints:

[0100] D full_max =min(D full_max1 , D full_max2 , D full_max3 ).

[0101] In some embodiments, in a non-fast charging scenario, such as under conventional charging current, the central axis of at least one of the first pole lug group 11 and the second pole lug group 12 is misaligned with the central axis of the corresponding electrode assembly 10 in the length direction, and the two groups of first pole lug groups 11 of the first electrode assembly 10a and the second electrode assembly 10b are staggered in the thickness direction Z of the battery cell 1, so that the orthographic projections of the two groups of first pole lug groups 11 of the first electrode assembly 10a and the second electrode assembly 10b in the thickness direction Z of the battery cell 1 have non-overlapping parts. In this case, the orthographic projections of the two groups of first pole lug groups 11 in the thickness direction Z of the battery cell 1 may overlap to a certain extent. In the width direction Y of the battery cell 1, the center distance between the two groups of first pole lug groups 11 of the first electrode assembly 10a and the second electrode assembly 10b is D2. The upper and lower limits of D2 need to comprehensively balance the electrical performance, welding reliability and structural stability, and D2 is between its maximum value D2max and minimum value D2min.

[0102] The minimum value of D2, D2min, is related to the following factors:

[0103] 1. Minimum contact area requirement: ensure that the effective contact area between the first tab group 11 and the first adapter 50 meets the non-fast charging current requirement;

[0104] in,

[0105] I max : Maximum operating current in non-fast charging scenarios, such as the current corresponding to a 1C rate;

[0106] J allow : Allowable current density, such as copper takes 2A-3A / mm 2 ;

[0107] C w : Width of the first adapter plate 50;

[0108] W 第一极耳组 : is the maximum width of the first electrode tab group 11.

[0109] 2. Welding Heat Affected Zone (HAZ) Isolation: Avoid soldering defects caused by the superposition of welding heat; D2 min2 ≥2·HAZ

[0110] Among them,

[0111] HAZ: Diameter of the welding heat affected zone. For laser welding, take 1 - 1.5 mm.

[0112] Considering the minimum contact area requirements of the first tab group 11 and the first adapter 50, and the isolation of the welding heat affected zone (HAZ), the minimum value D2 of the center distance D2 min Take the maximum value of the above constraint results:

[0113] D2 min = max(D2 min1 , D2 min2 ). On the other hand, the maximum value D2 of the center distance D2 max is related to the following factors:

[0114] 1. Coverage ability of the first adapter 50: Ensure that the first adapter 50 completely covers the misaligned area of the two groups of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b;

[0115] D2 max1 ≤C w -W 第一极耳组 -2·S edge

[0116] Among them,

[0117] C w : Width of the first adapter 50;

[0118] S edge : Edge safety margin of the first adapter 50, for example, 1 mm;

[0119] W 第一极耳组 : Maximum width of the first tab group 11.

[0120] 2. Mechanical strength limitation: Avoid vibration fatigue fracture caused by too long cantilever;

[0121]

[0122] Among them,

[0123] E: Elastic modulus of the material of the first adapter 50, for example, 120 GPa for copper;

[0124] I: Section moment of inertia of the first adapter 50, C T is the thickness of the first adapter 50, in mm;

[0125] F: Vibration load, such as 50 N;

[0126] L path : Current path length, related to D2 max2 Take K path ·D2 max2 , coefficient K path ≈1.2;

[0127] 3. Resistance increment control: An overly long misalignment path will increase the resistance and temperature rise.

[0128]

[0129] Among them,

[0130] ΔR allow : Allowable resistance increment, for example, 3% of the total internal resistance;

[0131] A cu : Cross-sectional area of the first adapter 50, for example, C w ·C T ;

[0132] ρ: Resistivity of the material of the first adapter 50, for example, for copper it is 1.68*10 -8 Ω·m;

[0133] L path : Current path length, related to D2 max3 Take K path ·D2 max3 , coefficient K path ≈1.2; Considering the above three factors of the covering ability, mechanical strength limitation and resistance increment control of the first adapter 50, the maximum value D2 of the center distance D2 max Take the minimum value of the above respective constraint results:

[0134] D2 max = min(D2 max1 , D2 max2 , D2 max3 )

[0135] Please refer to Figures 1 to 8 , below, the assembly process of the battery cell 1 in an embodiment of the application will be described in detail. Before that, it is also necessary to briefly introduce other structures of the battery cell 1, specifically the housing 40, the first end cap 20 and the second end cap 30.

[0136] During the assembly process of the battery cell 1, there are a core-unfolding stage and a core-combining stage. In the core-unfolding stage, the first electrode assembly 10a and the second electrode assembly 10b are respectively arranged on opposite sides of the first end cap 20 along the length direction of the electrode assembly 10, and the width direction of the first end cap 20 coincides with the length direction of the electrode assembly 10.

[0137] As Figure 1 shown, in an embodiment where the central axis of the first tab group 11 of the first electrode assembly 10a is offset from the central axis of the length direction of the first electrode assembly 10a, and the central axis of the first tab group 11 of the second electrode assembly 10b coincides with the central axis of the length direction of the second electrode assembly 10b, the two second tab groups 12 of the first electrode assembly 10a and the second electrode assembly 10b are offset along the width direction Y of the battery cell 1, and then the two second tab groups 12 of the first electrode assembly 10a and the second electrode assembly 10b are respectively welded to the second adapter plate 60 to fix the second adapter plate 60 and the two second tab groups 12 of the first electrode assembly 10a and the second electrode assembly 10b.

[0138] As Figure 3 and Figure 6 shown, in an embodiment where the central axis of the first tab group 11 of the first electrode assembly 10a is offset from the central axis of the length direction of the first electrode assembly 10a, the central axis of the first tab group 11 of the second electrode assembly 10b is also offset from the central axis of the length direction of the second electrode assembly 10b, and the central axes of the first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b are respectively located on both sides of the central axis of the length direction X of the battery cell 1, first, the portions of the two second tab groups 12 of the first electrode assembly 10a and the second electrode assembly 10b arranged along the length direction of the electrode assembly 10 are overlapped on the second adapter plate 60, or first, the two second tab groups 12 of the first electrode assembly 10a and the second electrode assembly 10b are offset along the width direction Y of the battery cell 1, and then the non-overlapping portions of the two second tab groups 12 projected in the thickness direction Z of the battery cell 1 are welded to the second adapter plate 60 to fix the second adapter plate 60 and the two second tab groups 12 of the first electrode assembly 10a and the second electrode assembly 10b.

[0139] As Figure 1 、 Figure 3 and Figure 4 、 Figures 6 to 8As shown, after fixing the two sets of second tab groups 12 of the second adapter piece 60 and the first electrode assembly 10a and the second electrode assembly 10b, the first electrode assembly 10a and the second electrode assembly 10b are stacked and enter the core combining stage. In this stage, the first end cap 20 seals an opening of the housing 40, the first electrode assembly 10a and the second electrode assembly 10b are loaded into the housing 40, and the two sets of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b extend out from the other opening of the housing 40. Then, the parts of the two sets of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b that do not overlap in the positive projection in the thickness direction Z of the battery cell 1 are respectively welded to the first adapter piece 50 to fix the first adapter piece 50 and the two sets of first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b. Finally, the second end cap 30 closes the other opening of the housing 40, and the assembly of the battery cell 1 is completed.

[0140] The present application also provides a battery, which includes the battery cell 1 described in any one of the above embodiments. The battery in the present application has the effects brought by any one of the above embodiments, so details are not described herein again.

[0141] The present application also provides an electrical device, which includes the battery described in any one of the above embodiments, and the battery is used to provide electrical energy for the electrical device. The electrical device in the present application has the effects brought by any one of the above embodiments, so details are not described herein again.

[0142] Among them, the electrical device can be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, an electric tool, a battery car, an electric vehicle, a ship, a spacecraft, etc. Among them, the electric toy can include a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy, an electric aircraft toy, etc., and the spacecraft can include an airplane, a rocket, a space shuttle, a spaceship, etc.

[0143] It should be understood that the technical solutions described in the embodiments of the present application are not limited to the electrical devices described above.

[0144] The battery cell 1, battery and electrical device are designed such that the central axis of at least one of the first tab group 11 and the second tab group 12 in the same electrode assembly is misaligned with the central axis of the length direction of the corresponding electrode assembly 10, and the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b are staggered in the thickness direction Z of the battery cell 1, so that there are non-overlapping parts in the orthographic projections of the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b in the thickness direction Z of the battery cell 1. In this case, the non-overlapping parts of the orthographic projections of the two first tab groups 11 of the first electrode assembly 10a and the second electrode assembly 10b in the thickness direction Z of the electrode assembly 10 are welded to the first pole or the first adapter 50 of the battery cell 1, so that the occurrence of poor welding such as cold welding and leaking welding due to the excessive thickness of the tab layer will not occur, and the welding difficulty is also reduced. In this way, the current capacity of the first electrode tab group 11 can also be guaranteed, the local temperature rise of the first electrode tab group 11 will not be too high, the internal impedance is small, and the battery cell 1 has a long cycle life and safety performance.

[0145] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0146] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A battery cell, characterized in that, The battery cell includes a first electrode assembly (10a) and a second electrode assembly (10b) which are stacked, and the first electrode assembly (10a) and the second electrode assembly (10b) are stacked along the thickness direction (Z) of the battery cell; Both the first electrode assembly (10a) and the second electrode assembly (10b) include a first tab group (11) and a second tab group (12). Along the length direction (X) of the battery cell, the first tab group (11) and the second tab group (12) are located at opposite ends of the corresponding electrode assembly (10). In the same electrode assembly, the central axis of at least one of the first tab group (11) and the second tab group (12) is offset from the central axis of the corresponding electrode assembly (10) in the length direction; The two first tab groups (11) of the first electrode assembly (10a) and the second electrode assembly (10b) are staggered in the thickness direction (Z) of the battery cell.

2. The battery cell according to claim 1, characterized in that, In the thickness direction (Z) of the battery cell, the orthographic projections of the two first tab groups (11) of the first electrode assembly (10a) and the second electrode assembly (10b) do not overlap.

3. The battery cell according to claim 2, wherein, In the width direction (Y) of the battery cell, the distance between the central axis of the first tab group (11) of the first electrode assembly (10a) and the central axis in the length direction of the first electrode assembly (10a) is deltA1, and the deltA1 is less than or equal to (0.5*W - 0.5*W 第一极耳组 ), where W is the width of the electrode assembly (10), and W 第一极耳组 is the maximum width of the first tab group (11); The central axis of the first tab group (11) of the second electrode assembly (10b) overlaps with the central axis of the second electrode assembly (10b) in the length direction.

4. The battery cell according to claim 3, wherein, The deltA1 is less than or equal to (0.25*W).

5. The battery cell according to claim 2, wherein, In the width direction (Y) of the battery cell, the distance between the central axis of the first tab group (11) of the first electrode assembly (10a) and the central axis in the length direction of the first electrode assembly (10a) is deltA1, and the distance between the central axis of the first tab group (11) of the second electrode assembly (10b) and the central axis in the length direction of the second electrode assembly (10b) is deltA2. The deltA1 is less than or equal to (0.5*W - 0.5*W 第一极耳组 ), and the deltA2 is less than or equal to (0.5*W - 0.5*W 第一极耳组 ), where W is the width of the electrode assembly (10), and W 第一极耳组 is the maximum width of the first tab group (11).

6. The battery cell according to claim 5, wherein In the width direction (Y) of the battery cell, the central axes of the first tab group (11) of the first electrode assembly (10a) and the first tab group (11) of the second electrode assembly (10b) are respectively located on both sides of the central axis of the battery cell in the length direction (X).

7. The battery cell according to claim 6, characterized in that, The first tab group (11) of the first electrode assembly (10a) and the first tab group (11) of the second electrode assembly (10b) are centrosymmetrically distributed about the central axis of the battery cell in the length direction (X).

8. The battery cell according to claim 7, characterized in that, In the width direction (Y) of the battery cell, the distance between the central axes of the first tab group (11) of the first electrode assembly (10a) and the central axes of the first tab group (11) of the second electrode assembly (10b) is deltA3, and the deltA3 is less than or equal to (W - W 第一极耳组 ) and greater than or equal to W 第一极耳组 . Preferably, the deltA3 is less than or equal to 0.5W.

9. A battery, characterized in that, A battery cell includes any one of the battery cells as described in claims 1 to 8 above.

10. An electrical device, characterized in that, A battery includes the battery as described in claim 9 above, and the battery is used to supply electrical energy to the electrical device.

Images