Single battery
By setting main and auxiliary tabs in the straight and corner areas of the electrode assembly and optimizing the tab structure, the problem of insufficient overcurrent capacity of the power square aluminum-cased battery was solved, and the safety and electrochemical performance of the battery were improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SUNWODA MOBILITY ENERGY TECHNOLOGY CO LTD
- Filing Date
- 2025-03-28
- Publication Date
- 2026-05-08
AI Technical Summary
Conventional power square aluminum-cased batteries have insufficient overcurrent capacity, resulting in uneven current density distribution, which affects battery safety and electrochemical performance.
The first main electrode tab is set in the straight area of the electrode assembly, and the first auxiliary electrode tab is set in the corner area. The electrode tab structure is optimized by multiple bends and cuts to ensure uniform current distribution and overcurrent capacity.
It improves the battery's overcurrent capacity and the uniformity of current density distribution, reduces resistance, and enhances battery safety and electrochemical performance.
Smart Images
Figure CN224217499U_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of battery technology, specifically relating to a single-cell battery. Background Technology
[0002] Lithium-ion power batteries have advantages such as small size, large capacity, high energy density, high charge and discharge rate, excellent low temperature performance, long service life and high safety.
[0003] Conventional power square aluminum-cased batteries only have one large tab per layer, resulting in insufficient current carrying capacity. Utility Model Content
[0004] Purpose of the utility model: The embodiments of this application provide a single battery cell, which aims to overcome the technical problem of insufficient overcurrent capacity of current power batteries.
[0005] Technical solution: The single cell disclosed in the embodiments of this application has intersecting first and second directions, and the single cell includes an electrode assembly;
[0006] The electrode assembly includes a first electrode, a diaphragm, and a second electrode. The first electrode, the diaphragm, and the second electrode are stacked and wound together. The electrode assembly includes a straight region and two corner regions connected to the straight region. The two corner regions are located on opposite sides of the straight region in the first direction. The electrode assembly includes a first side and a second side arranged opposite to each other in the second direction.
[0007] The electrode assembly further includes a first main electrode tab and a first auxiliary electrode tab with the same polarity. The first main electrode tab and the first auxiliary electrode tab are both connected to the first electrode plate and are both located on the first side. The first main electrode tab is located in the straight area, and the first auxiliary electrode tab is located in at least one of the corner areas.
[0008] In some embodiments, the first electrode includes a first straight section and a first corner section connected together, the first straight section having a plurality of segments and being stacked in the straight region, and the first corner section having a plurality of segments and being stacked in the corner region;
[0009] Multiple first straight sections are provided with the first main electrode tab, and multiple first corner sections are provided with the first auxiliary electrode tab.
[0010] In some embodiments, the first electrode has an unfolding direction, the first auxiliary electrode tab includes a plurality of first bends, the plurality of first bends are connected to the same first corner segment, and the plurality of first bends are arranged along the unfolding direction of the first electrode; when the electrode assembly is in a wound state, at least two of the first bends are bent and stacked in the second direction and electrically connected.
[0011] In some embodiments, two adjacent first bends located on the same first corner segment are stacked in the second direction;
[0012] And / or, the first bends of two adjacent layers of the first corner segments located in the same corner area are stacked in the second direction.
[0013] In some embodiments, the first auxiliary electrode tab has multiple slits, which are spaced apart along the unfolding direction of the first electrode sheet, and one slit is provided between two adjacent first bending portions.
[0014] In some embodiments, each layer of the first corner segment is provided with the first auxiliary electrode tab, and the length of the first auxiliary electrode tab in the unfolding direction is equal to the length of the first corner segment in the unfolding direction.
[0015] In some embodiments, each of the first straight sections of each layer is provided with the first main electrode tab, and when the electrode assembly is in a wound state, the first main electrode tab is bent and stacked in the second direction.
[0016] In some embodiments, the first electrode further includes a first electrodeless tab segment located at the winding start end of the first electrode, the first electrodeless tab segment being connected to the first straight segment or the first corner segment, and the first electrodeless tab segment being wound at least two turns.
[0017] In some embodiments, the first main electrode tab and the first straight segment have equal lengths in the first direction;
[0018] The first auxiliary electrode tab also includes a first base, which is connected between the first corner segment and the first bend. The length of the first base and the corresponding first corner segment are equal in the unfolding direction of the first electrode sheet, and the first base is connected to the first main electrode tab.
[0019] In some embodiments, the electrode assembly further includes a second main electrode and a second auxiliary electrode, both the second main electrode and the second auxiliary electrode are disposed on the second electrode plate, and the second main electrode and the second auxiliary electrode have the same polarity and are both located on the second side. The polarity of the second main electrode is opposite to that of the first main electrode. The second main electrode is located in the straight region, and the second auxiliary electrode is located in at least one of the corner regions.
[0020] In some embodiments, the single-cell battery further includes:
[0021] A housing having a receiving cavity;
[0022] A first pole and a second pole, wherein the first pole is disposed on the housing and located on the first side, and the second pole is disposed on the housing and located on the second side, and at least one of the first pole and the second pole is insulated from the housing; the first main pole and the first auxiliary pole are both electrically connected to the first pole, and the second main pole and the second auxiliary pole are both electrically connected to the second pole.
[0023] This application also discloses a battery pack, including the single battery cells as described in the above embodiments.
[0024] Beneficial Effects: The single-cell battery of this application embodiment has intersecting first and second directions. The single-cell battery includes an electrode assembly: the electrode assembly includes a first electrode, a separator, and a second electrode, which are stacked and wound together. The electrode assembly includes a flat region and two corner regions connected to the flat region. The two corner regions are located on opposite sides of the flat region in the first direction. The electrode assembly includes a first side and a second side arranged opposite to each other in the second direction. The electrode assembly also includes a first main electrode tab and a first auxiliary electrode tab of the same polarity. Both the first main electrode tab and the first auxiliary electrode tab are connected to the first electrode and are located on the first side. The first main electrode tab is located in the flat region, and the first auxiliary electrode tab is located in at least one corner region. By setting the first main electrode tab in the flat region of the electrode assembly and setting the first auxiliary electrode tab in at least one corner region of the electrode assembly, compared with setting the electrode tab only in the flat region, a greater current-carrying capacity is achieved on the first side of the electrode assembly, ensuring the safety and electrochemical performance of the battery.
[0025] The battery pack of this application embodiment includes the single battery cell as described in the above embodiments. Therefore, it can have all the technical features and effects of the single battery cell described above, which will not be repeated here. Attached Figure Description
[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0027] Figure 1 This is a schematic diagram of the structure of a single battery cell according to an embodiment of this application;
[0028] Figure 2 This is a top view of the winding of the electrode assembly in a single cell according to an embodiment of this application, and only the first electrode and the first tabless section are shown in the figure;
[0029] Figure 3 This is a top view of the electrode assembly in a single cell according to an embodiment of this application, showing the first main electrode and the first auxiliary electrode.
[0030] Figure 4 This is a top view of the electrode assembly in a single battery cell according to an embodiment of this application after it has been flattened, and the first bending portion is shown in the figure.
[0031] Figure 5 This is a schematic diagram of the structure of the first electrode in the unfolded state of a single cell in an embodiment of this application;
[0032] Figure 6 This is a schematic diagram of the structure of the second electrode in the unfolded state of a single cell in an embodiment of this application;
[0033] Figure 7 This is an internal cross-sectional view of a single cell according to an embodiment of this application, showing the positional relationship of the first electrode, the second electrode, and the separator.
[0034] Explanation of reference numerals in the attached drawings: X, first direction; Y, second direction; 10, electrode assembly; 11, first electrode; 12, second electrode; 13, diaphragm; 101, straight section; 102, corner section; 103, first side; 104, second side; 14, first main electrode tab; 15, first auxiliary electrode tab; 111, first straight section; 112, first corner section; L, unfolding direction; 151, first bending section; 150, slit; 100, first electrodeless section; 152, first base; 16, second main electrode tab; 17, second auxiliary electrode tab; 20, housing; 200, receiving cavity; 30, first electrode post; 40, second electrode post. Detailed Implementation
[0035] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.
[0036] In the description of this application, it should be understood that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or component 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 application. In the description of this application, "multiple" means two or more, and "at least one" can refer to one, two, or more, unless otherwise explicitly specified. The terms "first," "second," and "third," etc., are only for the convenience of description and are used to name parts or embodiments by number, and do not imply any order of importance between the parts or embodiments.
[0037] It should also be noted that in the accompanying drawings of this application, the arrow marked X indicates the first direction X or its opposite direction, the arrow marked Y indicates the second direction Y or its opposite direction, and the arrow marked Z indicates the third direction or its opposite direction. The introduction of the first direction X, the second direction Y, and the unfolding direction L in the description of this application is to more clearly define the structure and relative positional relationships of the components in a single cell. In actual implementation, the second direction Y is generally a vertical direction or a height direction, and the first direction X is generally a horizontal direction, intersecting the second direction Y. Optionally, the first direction X is perpendicular to the second direction Y to optimize the layout of the single cell. In the description of this application, "perpendicular" means completely perpendicular to 90° or almost completely perpendicular; for example, an angle between 80° and 100° is considered perpendicular. Similarly, "parallel" means completely parallel or almost completely parallel; for example, a completely parallel angle within 10° is considered parallel.
[0038] As a preamble to the embodiments of this application, lithium-ion power batteries have advantages such as small size, large capacity, high energy density, high charge / discharge rate, excellent low-temperature performance, long service life, and high safety. However, conventional square aluminum-cased power batteries only have one large tab die-cut per layer, resulting in insufficient overcurrent capacity, uneven current density distribution, and easy lithium plating during charge and discharge, affecting battery safety and electrochemical performance. Furthermore, when assembling the electrode sheets into the casing after winding, the large tabs are located on the straight edge of the core body. This requires first gathering and welding the large tab ends together, then welding the welded tabs to the adapter plate, and finally connecting the adapter plate to the cover plate electrode post using laser welding. This welding process is cumbersome. The tabs undergo a bend at the gathering point in different directions, and a second bend occurs at the welding point with the adapter plate. These two bends result in excessively long tab leads, low foil utilization, and excessively high tab height after welding with the adapter plate, occupying internal battery space and affecting battery energy density.
[0039] In view of this, embodiments of this application provide a single-cell battery, which aims to solve at least one of the above-mentioned technical problems.
[0040] Please see Figure 1 and Figure 2 As shown, the single cell in this embodiment has intersecting first direction X and second direction Y. The single cell includes an electrode assembly 10, which includes a first electrode 11, a separator 13, and a second electrode 12. The first electrode 11, the separator 13, and the second electrode 12 are stacked and wound together (e.g., Figure 7The electrode assembly 10 includes a flat region 101 and two corner regions 102 connected to the flat region 101. The two corner regions 102 are located on opposite sides of the flat region 101 in a first direction X. The electrode assembly 10 includes a first side 103 and a second side 104 disposed opposite to each other in a second direction Y. It should be understood that the first electrode 11 can correspond to the positive electrode of a single cell, and the second electrode 12 can correspond to the negative electrode of a single cell. The electrode assembly 10 also includes a first main electrode tab 14 and a first auxiliary electrode tab 15 of the same polarity. The first main electrode tab 14 and the first auxiliary electrode tab 15 are both connected to the first electrode tab 11 and are both located on the first side 103. The first main electrode tab 14 is located in the flat region 101, and the first auxiliary electrode tab 15 is located in at least one corner region 102.
[0041] It should be understood that the first side 103 can be the lead-out side of the positive electrode tab, and the second side 104 can be the lead-out side of the negative electrode tab; there is no limitation on this. For example, both the first main electrode tab 14 and the first auxiliary electrode tab 15 are positive electrodes. By setting the first main electrode tab 14 in the straight region 101 of the electrode assembly 10 and setting the first auxiliary electrode tab 15 in at least one corner region 102 of the electrode assembly 10, the first side 103 of the electrode assembly 10 has a greater current-carrying capacity.
[0042] Please see Figure 3 and Figure 4 As shown, in some embodiments, the two corner regions 102 of the electrode assembly 10 are each connected to a first auxiliary tab 15, so that the straight region 101 and the two corner regions 102 of the electrode assembly 10 are both provided with tabs, which further improves the overcurrent capacity and improves the uniformity of the current density distribution, ensuring the safety and electrochemical performance of the battery.
[0043] Please see Figures 1 to 4 As shown, in some embodiments, the first electrode 11 includes a first straight section 111 and a first corner section 112 connected together. Multiple first straight sections 111 are provided and stacked in the straight region 101, and multiple first corner sections 112 are provided and stacked in the corner region 102. Multiple first straight sections 111 are provided with first main tabs 14, and multiple first corner sections 112 are provided with first auxiliary tabs 15. It should be understood that the electrode assembly 10 of this application is formed by stacking and winding a first electrode 11, a diaphragm 13, and a second electrode 12. By providing first main tabs 14 on each of the multiple first straight sections 111 and first auxiliary tabs 15 on each of the multiple first corner sections 112, the current-carrying capacity of the electrode assembly 10 is further improved. This ensures that current can be transmitted through the tabs on all multiple electrode layers, improving the current-carrying capacity. Additionally, it shortens the current transmission path and reduces resistance.
[0044] It should be noted that: after being stacked, the first straight section 111 roughly forms the main part of the straight region 101, and the remaining part is mainly the diaphragm 13 located in the straight region 101, which will not be described in detail.
[0045] Please see Figure 5 As shown, in some embodiments, the first electrode 11 has an unfolding direction L, and the first auxiliary electrode tab 15 includes a plurality of first bending portions 151. The plurality of first bending portions 151 are connected to the same first corner segment 112, and the plurality of first bending portions 151 are arranged along the unfolding direction L of the first electrode 11. When the electrode assembly 10 is in a wound state, at least two first bending portions 151 are bent and stacked in the second direction Y and electrically connected. By using a plurality of first bending portions 151 arranged along the unfolding direction L of the first electrode 11, the difficulty of bending the bending portions can be reduced, ensuring that the first auxiliary electrode tab 15 can be smoothly flattened when the electrode assembly 10 is wound and the tab flattening step is performed. At the same time, it reduces the probability of wrinkles, deformation, and damage on the first auxiliary electrode tab 15 during the flattening process. In addition, by stacking at least two first bending portions 151 in the second direction Y after bending, on the one hand, the current conduction between the inner and outer layers after the electrode is wound is realized, further reducing the internal resistance of the battery; on the other hand, the space occupied by the first bending portions 151 in the second direction Y after bending is reduced; in addition, stress transmission between the first bending portions 151 is also made more uniform, and the stability of the first auxiliary electrode tab 15 is improved.
[0046] Please see Figure 4 As shown, in some embodiments, two adjacent first bends 151 located on the same first corner segment 112 are stacked in the second direction Y. It should be understood that by overlapping and connecting adjacent first bends 151 on the same layer, multiple first bends 151 are evenly distributed on the first side 103, forming a stable connection between adjacent first bends 151. This improves the overall structural stability of the first auxiliary electrode 15 and reduces the risk of tearing under stress. Simultaneously, it improves the uniformity of current transmission density in the first auxiliary electrode 15 and increases heat dissipation capacity.
[0047] Please continue reading. Figure 4 As shown, in some embodiments, the first bent portions 151 of two adjacent layers of the first corner segment 112 located in the same corner region 102 are stacked in the second direction Y. It should be understood that by connecting the two adjacent layers of the first bent portions 151 located in the same corner region 102 in the second direction Y, current conduction between the inner and outer layers after the electrode is wound is achieved, further reducing the internal resistance of the battery; on the other hand, stress transmission between the first bent portions 151 is made more uniform, and the stability of the first auxiliary electrode tab 15 is improved.
[0048] Please see Figure 4As shown, in some embodiments, two adjacent first bends 151 located on the same first corner segment 112 are stacked in the second direction Y; simultaneously, the first bends 151 of two adjacent layers of first corner segments 112 located in the same corner region 102 are stacked in the second direction Y. It should be understood that by stacking and connecting adjacent first bends 151 on the same layer and stacking and connecting first bends 151 on the second direction Y of adjacent layers, the first auxiliary electrode 15 has a three-dimensional structure, which further increases the structural stability of the first auxiliary electrode 15; at the same time, it makes the current distribution uniform throughout the entire range, reduces the internal resistance of the battery, and improves the overcurrent capacity of the battery.
[0049] Please see Figure 5 As shown, in some embodiments, the first auxiliary electrode tab 15 has multiple slits 150, which are spaced apart along the unfolding direction L of the first electrode sheet 11, and a slit 150 is provided between two adjacent first bending portions 151. It should be understood that the corner area 102 is the area with the greatest winding deformation. The slits 150 divide the continuous electrode sheet material into independent bending units, avoiding stress concentration during bending that could lead to breakage. By providing multiple slits 150 on the first auxiliary electrode tab 15, the difficulty of flattening the first auxiliary electrode tab 15 is reduced, and the redundancy that occurs after flattening the electrode tab is also reduced. At the same time, the slits 150 allow the first bending portions 151 to be staggered and nested during stacking, reducing abrupt thickness changes in local positions of the electrode tab and improving the compactness of the electrode assembly 10. In other embodiments, by arranging multiple first bending portions 151 at intervals along the unfolding direction L on the first electrode 11, a blank area is formed between adjacent first bending portions 151. On the one hand, this reduces material stacking and improves the problem of large-area protrusions after the first bending portions 151 overlap, thus improving compactness. On the other hand, it improves the flexibility of the first bending portions 151, reduces bending deformation, improves the uniformity of the current path, and reduces internal resistance.
[0050] It should be noted that: the slit 150 can be a tangent, and the interval of the slit 150 in the unfolding direction L is 0 or almost 0, so that the cut surfaces of two adjacent first bending portions 151 after cutting are roughly in contact, but each first bending portion 151 is independent of each other; or the slit 150 can have a relatively large dimension in the unfolding direction L, in which case there is a gap between adjacent first bending portions 151, such as Figure 5 The obvious intervals shown will not be elaborated upon further.
[0051] In some embodiments, each first corner segment 112 of each layer is provided with a first auxiliary electrode tab 15, the length of the first auxiliary electrode tab 15 in the unfolding direction L is equal to the length of the first corner segment 112 in the unfolding direction L. It should be understood that by providing a first auxiliary electrode tab 15 on each first corner segment 112 of the first electrode sheet 11, each first corner segment 112 of the corner region 102 is connected to an electrode tab, reducing the current path length; and the fact that the length of the first auxiliary electrode tab 15 in the unfolding direction L is equal to the length of the first corner segment 112 in the unfolding direction L ensures that the entire first corner segment 112 covers the first bent portion 151, further increasing the conductive area of the electrode tab, reducing contact resistance, improving the uniformity of current distribution, and reducing local overheating. Providing the first bent portion 151 throughout the entire segment may enhance the structural strength of the corner region 102, because the bend increases the number of material layers, and the shape of the bend can disperse stress and prevent cracking. The overlapping of the bent portions in each layer may form a stacked structure, increasing overall stability. Meanwhile, the above structure can increase the heat dissipation area and improve heat dissipation efficiency. It should be noted that: the entire first corner segment 112 refers to the entire first corner segment 112 in the L direction after it is unfolded.
[0052] Please see Figure 3 As shown, in some embodiments, each layer's first straight section 111 is provided with a first main electrode tab 14. When the electrode assembly 10 is in a wound state, the first main electrode tab 14 is bent and stacked in the second direction Y. It should be understood that the first main electrode tab 14 is located in the straight area 101 rather than the corner area 102, avoiding the high-stress area during winding (the corner area 102 is prone to cracking due to winding tension), reducing the risk of electrode tab breakage. The flatness of the electrode sheet in the straight area 101 is high, and the deformation consistency of the first main electrode tab 14 after bending is better (the corner area 102 is prone to material delamination when bent due to its small radius of curvature). If the stacked connection is achieved by welding / riveting, the contact stability is improved. The multi-layer main electrode tabs disperse the current density and reduce local heat generation. The stacked first main electrode tabs 14 have a short heat conduction path and better heat dissipation.
[0053] Please see Figure 5 As shown, in some embodiments, the first electrode 11 further includes a first tabless section 100, which is located at the starting end of the winding of the first electrode 11. The first tabless section 100 is connected to the first straight section 111 or the first corner section 112, and the first tabless section 100 is wound at least two turns. It should be understood that by setting the first tabless section 100, the abnormal overlap and damage of the inner ring electrode tabs after the flattening process are ensured, thereby improving the safety of the single cell.
[0054] The first electrode section 100 is wound at least two turns so that the first side 103 of the electrode assembly 10 near the central region can be left empty, so as to reserve the space occupied by the first main electrode 14 after bending, and to prevent the parts of the first main electrode 14 in the central region from colliding and interfering with each other and being unable to be stacked.
[0055] Please see Figure 5 As shown, in some embodiments, the first main electrode tab 14 and the first straight segment 111 have the same length in the first direction X; the first auxiliary electrode tab 15 further includes a first base 152, which connects the first corner segment 112 and the first bent portion 151. The first base 152 and the corresponding first corner segment 112 have the same length in the unfolding direction L of the first electrode 11, and the first base 152 is connected to the first main electrode tab 14.
[0056] It is important to understand that the first base 152 facilitates the transition between the first corner segment 112 and the first bent portion 151. Simultaneously, the first base 152 supports the bending action of the first bent portion 151, preventing the flattened first bent portion 151 from connecting with the first corner segment 112, reducing the risk of damage to the first electrode 11 and the first auxiliary electrode tab 15, and improving the safety of the individual battery. The first base 152 and the first corner segment 112 are of equal length to enhance the support for the first bent portion 151, allowing for a more uniform distribution of stress generated during bending. Furthermore, the first base 152 connects to the first main electrode tab 14, enabling current transmission between the first main electrode tab 14 and the first auxiliary electrode tab 15. Combined with the fact that the first main electrode tab 14 and the first straight segment 111 are of equal length, the tabs achieve full coverage of the first electrode 11 on the first side 103 of the electrode assembly 10, significantly improving the overcurrent capacity of the individual battery and resulting in a more uniform current density distribution.
[0057] Please see Figure 6 As shown, in some embodiments, the electrode assembly 10 further includes a second main electrode tab 16 and a second auxiliary electrode tab 17. Both the second main electrode tab 16 and the second auxiliary electrode tab 17 are disposed on the second electrode plate 12, and the second main electrode tab 16 and the second auxiliary electrode tab have the same polarity and are both located on the second side 104. The polarity of the second main electrode tab 16 is opposite to that of the first main electrode tab 14. The second main electrode tab 16 is located in the straight region 101, and the second auxiliary electrode tab 17 is located in at least one corner region 102. It should be understood that the structure of the second main electrode tab 16 can be the same as the structure of the first main electrode tab 14, and the structure of the second auxiliary electrode tab 17 can be the same as the structure of the first auxiliary electrode tab 15.
[0058] Please see Figure 1As shown, in some embodiments, the single battery cell further includes: a housing 20, a first terminal 30, and a second terminal 40. The housing 20 has a receiving cavity 200. The first terminal 30 is disposed on the housing 20 and located on a first side 103, and the second terminal 40 is disposed on the housing 20 and located on a second side 104. At least one of the first terminal 30 and the second terminal 40 is insulated from the housing 20. The first main electrode 14 and the first auxiliary electrode 15 are both electrically connected to the first terminal 30, and the second main electrode 16 and the second auxiliary electrode 17 are both electrically connected to the second terminal 40. It should be understood that by directly connecting the first main electrode 14 and the first auxiliary electrode 15 to the first terminal 30, and by directly connecting the second main electrode 16 and the second auxiliary electrode 17 to the second terminal 40, the compactness of the battery structure is improved, and the space utilization is increased. At the same time, the current transmission path between the electrode and the terminal is shortened, and the contact resistance is reduced. The insulation of one of the first terminal 30 and the second terminal 40 from the housing 20 can prevent short circuits caused by the conductivity of the housing 20.
[0059] This application also discloses a battery pack, including the single battery cells as described in the above embodiments. Therefore, it can possess all the technical features and effects of the aforementioned single battery cells, which will not be repeated here.
[0060] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.
[0061] The single-cell battery and battery pack provided in the embodiments of this application have been described in detail above, and specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.
Claims
1. A single-cell battery having intersecting first direction (X) and second direction (Y), characterized in that, Includes electrode assembly (10); The electrode assembly (10) includes a first electrode (11), a diaphragm (13), and a second electrode (12). The first electrode (11), the diaphragm (13), and the second electrode (12) are stacked and wound together. The electrode assembly (10) includes a flat region (101) and two corner regions (102) connected to the flat region (101). The two corner regions (102) are located on opposite sides of the flat region (101) in the first direction (X). The electrode assembly (10) includes a first side (103) and a second side (104) arranged opposite to each other in the second direction (Y). The electrode assembly (10) further includes a first main electrode tab (14) and a first auxiliary electrode tab (15) of the same polarity. The first main electrode tab (14) and the first auxiliary electrode tab (15) are both connected to the first electrode plate (11) and are both located on the first side (103). The first main electrode tab (14) is located in the straight area (101), and the first auxiliary electrode tab (15) is located in at least one of the corner areas (102).
2. The single-cell battery according to claim 1, characterized in that, The first electrode (11) includes a first straight section (111) and a first corner section (112) connected together. The first straight section (111) is provided in multiple ways and is stacked in the straight area (101). The first corner section (112) is provided in multiple ways and is stacked in the corner area (102). Multiple first straight sections (111) are provided with first main electrode tabs (14), and multiple first corner sections (112) are provided with first auxiliary electrode tabs (15).
3. The single-cell battery according to claim 2, characterized in that, The first electrode (11) has an unfolding direction (L), and the first auxiliary electrode tab (15) includes a plurality of first bends (151). The plurality of first bends (151) are connected to the same first corner segment (112). The plurality of first bends (151) are arranged along the unfolding direction (L) of the first electrode (11). When the electrode assembly (10) is in a wound state, at least two first bends (151) are bent and stacked in the second direction (Y) and electrically connected.
4. The single-cell battery according to claim 3, characterized in that, Two adjacent first bends (151) located on the same first corner segment (112) are stacked in the second direction (Y); And / or, the first bends (151) of two adjacent layers of the first corner segments (112) located in the same corner area (102) are stacked in the second direction (Y).
5. The single-cell battery according to claim 3, characterized in that, The first auxiliary electrode tab (15) is provided with multiple slits (150), which are spaced apart along the unfolding direction (L) of the first electrode plate (11), and one slit (150) is provided between two adjacent first bending portions (151).
6. The single-cell battery according to claim 3, characterized in that, Each first corner segment (112) of each layer is provided with a first auxiliary electrode tab (15), and the length of the first auxiliary electrode tab (15) in the unfolding direction (L) is equal to the length of the first corner segment (112) in the unfolding direction (L).
7. The single-cell battery according to claim 6, characterized in that, Each first straight section (111) of each layer is provided with a first main electrode tab (14). When the electrode assembly (10) is in a wound state, the first main electrode tab (14) is bent and stacked in the second direction (Y).
8. The single-cell battery according to claim 7, characterized in that, The first electrode (11) further includes a first electrodeless tab (100), which is located at the winding start end of the first electrode (11). The first electrodeless tab (100) is connected to the first straight section (111) or the first corner section (112), and the first electrodeless tab (100) is wound at least two turns.
9. The single-cell battery according to claim 8, characterized in that, The first main electrode tab (14) and the first straight segment (111) have the same length in the first direction (X); The first auxiliary electrode tab (15) further includes a first base (152), which is connected between the first corner segment (112) and the first bend (151). The length of the first base (152) and the corresponding first corner segment (112) in the unfolding direction (L) of the first electrode plate (11) is equal, and the first base (152) is connected to the first main electrode tab (14).
10. The single-cell battery according to any one of claims 1-9, characterized in that, The electrode assembly (10) further includes a second main electrode tab (16) and a second auxiliary electrode tab (17). The second main electrode tab (16) and the second auxiliary electrode tab (17) are both disposed on the second electrode plate (12), and the second main electrode tab (16) and the second auxiliary electrode tab have the same polarity and are both located on the second side (104). The polarity of the second main electrode tab (16) is opposite to that of the first main electrode tab (14). The second main electrode tab (16) is located in the straight area (101), and the second auxiliary electrode tab (17) is located in at least one of the corner areas (102).