Battery cell and battery

Abstract

The utility model provides a battery cell and battery, the battery cell comprises a battery cell body and tabs, the tabs are arranged at one axial end of the battery cell body, a plurality of tabs are arranged along the circumferential direction of the battery cell body at intervals, and one end of each tab close to the circumferential edge of the battery cell body forms a convex part. Each tab comprises a plurality of single tabs which are stacked in the axial direction of the battery cell body, and the distances between the single tabs and the axis of the battery cell body are sequentially reduced in the direction close to the battery cell body. According to the battery cell disclosed by the invention, the plurality of single tabs are matched and stacked along the axial direction of the battery cell body to form the tabs, and the distances between the plurality of single tabs and the axis of the battery cell body are sequentially reduced along the direction close to the battery cell body, so that the safety of the structure of the battery cell is ensured, and the good overcurrent capability of the tabs is ensured; therefore, the problems that in the prior art, safety risks are prone to occurring and the overcurrent capacity is poor in the process that the tabs are assembled into the battery are solved.

Description

Technical Field

[0001] This utility model relates to the field of battery-related technology, specifically to a battery cell and a battery. Background Technology

[0002] In the manufacturing process of cylindrical batteries, the design of the tabs is crucial to the battery's performance and safety. As a key component connecting the internal and external circuitry of the cell, the design of the tabs not only affects the battery's discharge and overcurrent capabilities but also directly relates to its safety. In traditional cylindrical battery designs, the dimensions and height of the inner and outer tabs are usually kept consistent after molding. This design simplifies the manufacturing process to some extent but also introduces several technical challenges.

[0003] Specifically, when the height of the inner tab after forming is close to the position of the center hole of the core, the tab may touch the center hole during battery assembly or charging / discharging, especially when the battery is subjected to external pressure or vibration, further increasing the risk of this contact. Once the tab contacts the center hole, it may cause an internal short circuit, leading to safety issues such as battery overheating, expansion, or even explosion. To avoid this risk, one possible solution is to reduce the height of the tab, but this would reduce the tab's current carrying capacity, affecting the battery's discharge performance and energy density.

[0004] Overcurrent capability, or the battery's ability to operate stably at high discharge rates, is one of the important indicators for measuring battery performance. The height and width of the tabs directly affect their conductivity. Lower tabs not only increase the internal contact resistance of the battery, leading to voltage drop and energy loss during discharge, but may also melt due to localized overheating during high-current discharge, further affecting the battery's lifespan and safety.

[0005] As can be seen from the above, the current electrode tabs are prone to safety risks and poor overcurrent capacity during the battery assembly process. Utility Model Content

[0006] The main objective of this invention is to provide a battery cell and battery to solve the problems of safety risks and poor overcurrent capacity that may occur when the tabs are assembled into batteries in the prior art.

[0007] To achieve the above objectives, according to one aspect of the present invention, a battery cell is provided. The battery cell includes a battery cell body and electrode tabs. The electrode tabs are disposed at one end of the axial direction of the battery cell body. Multiple electrode tabs are provided and spaced apart along the circumferential direction of the battery cell body. A protrusion is formed at the end of the electrode tab near the peripheral edge of the battery cell body. Each electrode tab includes multiple single electrode tabs stacked along the axial direction of the battery cell body. Along the direction close to the battery cell body, the distance between the multiple single electrode tabs and the axis of the battery cell body decreases sequentially.

[0008] Furthermore, the plurality of single-piece tabs includes a number of first single-piece tabs and a number of second single-piece tabs. The second single-piece tabs are disposed on the side of the first single-piece tabs away from the cell body. The first single-piece tabs extend radially along the cell body. The second single-piece tabs have protrusions and extension sections extending radially along the cell body.

[0009] Furthermore, the protrusion includes a first arm segment and a second arm segment that are bent. One end of the first arm segment is connected to the cell body, and the other end of the first arm segment extends along the axial direction of the cell body and is connected to the first end of the second arm segment. The second end of the second arm segment extends toward the side of the cell body and close to the axis of the cell body and is connected to the extension segment.

[0010] Furthermore, the protrusions of the multiple second single-piece tabs have the same bending angle and are fitted together.

[0011] Furthermore, there is one first monolithic electrode tab and multiple second monolithic electrode tabs, with the first monolithic electrode tab and the extension of the adjacent second monolithic electrode tab stacked together.

[0012] Furthermore, at least one of the multiple tabs is a positive tab, and at least another is a negative tab; and / or a single tab has a trapezoidal structure; and / or along the axial direction of the cell body, the projection of the tab onto the end face of the cell body has a trapezoidal structure.

[0013] Furthermore, the battery cell is formed by winding an electrode sheet and a separator. The electrode sheet has multiple single-piece tabs arranged at intervals along its length. The height of the multiple single-piece tabs increases sequentially. Among two adjacent single-piece tabs, the taller single-piece tab is stacked on the side of the shorter single-piece tab away from the battery cell body.

[0014] According to another aspect of the present invention, a battery is provided, the battery including a busbar and the aforementioned battery cell, the busbar being disposed on top of the battery cell, the busbar having a groove structure, and at least a portion of the battery cell's tabs being disposed inside the groove structure.

[0015] Furthermore, multiple slot structures are provided, with the multiple slot structures spaced apart along the circumference of the manifold, and each slot structure corresponds to a tab.

[0016] Furthermore, the bottom surface of the slot structure has a first portion that abuts against the second arm segment of the protrusion of the electrode tab of the battery cell, and the bottom surface of the slot also has a second portion that abuts against the extension segment of the electrode tab.

[0017] Furthermore, the battery also includes a casing and a thermally conductive colloid, with the battery cell and busbar disposed inside the casing, and the thermally conductive colloid disposed between the first arm of the protrusion and the inner wall surface of the casing.

[0018] By applying the technical solution of this utility model, this application uses multiple single-piece tabs stacked along the axial direction of the cell body to form tabs, which helps to strengthen the structural strength of the tabs. At the same time, the structural arrangement of multiple single-piece tabs with progressively decreasing distances from the axis of the cell body along the direction closer to the cell body avoids the phenomenon that the tabs may touch the center hole of the winding core during battery assembly or charging and discharging, thereby ensuring the structural safety of the cell. In addition, the multi-layer arrangement of the tab structure in this application also ensures that the tabs have good overcurrent capacity, optimizes the current distribution, and helps to improve the performance of the cell.

[0019] The tab spacing used in this application is located on the cell body, which helps to save materials, improve installation efficiency, and thus improve battery assembly efficiency. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:

[0021] Figure 1 A schematic diagram of the electrode sheet in its unfolded state is shown.

[0022] Figure 2 A side view of the structure of the electrode tab of this utility model is shown;

[0023] Figure 3 A top view of the battery cell body and electrode tabs of this utility model is shown;

[0024] Figure 4 A three-dimensional structural schematic diagram of the busbar of this utility model is shown;

[0025] Figure 5 A three-dimensional structural schematic diagram of another manifold of this utility model is shown;

[0026] Figure 6 A cross-sectional view of the manifold and electrode tabs of this utility model is shown.

[0027] The above figures include the following reference numerals:

[0028] 10. Electrode; 110. Tab; 111. Single tab; 1110. First single tab; 1120. Second single tab; 1121. First arm segment; 1122. Second arm segment; 1123. Extension segment; 20. Cell body; 30. Busbar; 310. Slot structure; 320. Raised structure. Detailed Implementation

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0031] In this utility model, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" are generally used in relation to the direction shown in the accompanying drawings, or in relation to the vertical, perpendicular, or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not used to limit this utility model.

[0032] To address the safety risks and poor overcurrent capacity issues that exist in the prior art during battery assembly, this application provides a battery cell formed by winding an electrode 10 and a separator. The electrode 10 includes a positive electrode and a negative electrode, with a positive electrode tab and a negative electrode tab respectively disposed on the positive electrode and the negative electrode.

[0033] The electrode 10 and the separator are wound to form a cylindrical battery cell body 20 and a tab 110 is provided at one end of the axial direction of the battery cell body 20. That is, the part of the electrode 10 except for the tab 110 and the separator are wound to form a cylindrical battery cell body 20. The tab 110 is bent and provided at one end of the axis of the battery cell body 20 and extends approximately along the radial direction of the battery cell body 20.

[0034] like Figures 1 to 3 As shown, the battery cell includes a battery cell body 20 and tabs 110. The tabs 110 are disposed at one end of the axial direction of the battery cell body 20. Multiple tabs 110 are provided and are spaced apart along the circumference of the battery cell body 20. A protrusion is formed at one end of the tab near the circumferential edge of the battery cell body 20. Each tab 110 includes multiple single tabs 111 stacked along the axial direction of the battery cell body 20. Along the direction close to the battery cell body 20, the distance between the multiple single tabs 111 and the axis of the battery cell body 20 decreases sequentially.

[0035] Among them, the height of the protrusion gradually decreases along the axial direction close to the cell body 20.

[0036] Specifically, this application employs multiple single-piece tabs 111 stacked along the axial direction of the cell body 20 to form tabs 110, which helps to strengthen the structural strength of the tabs 110. At the same time, the structural arrangement of multiple single-piece tabs 111 with the distance between them and the axis of the cell body 20 decreasing sequentially along the direction close to the cell body 20 avoids the phenomenon that the tabs 110 may touch the center hole of the winding core during battery assembly or charging and discharging, thereby ensuring the structural safety of the cell. In addition, the multi-layer arrangement of the tabs 110 structure in this application also ensures that the tabs 110 have good overcurrent capacity, optimizes the current distribution, and helps to improve the performance of the cell.

[0037] In this embodiment, the tabs 110 are spaced apart on the cell body 20, which helps to save materials, improve installation efficiency, and thus improve the battery assembly efficiency.

[0038] Among them, some of the multiple tabs 110 are positive tabs, and the other part are negative tabs.

[0039] In this embodiment, along the axial direction of the cell body 20, the projection of the tab 110 on the end face of the cell body 20 is approximately trapezoidal. Each of the multiple individual tabs 111 forming the tab 110 is trapezoidal, and each individual tab 111 is arranged in a trapezoidal structure; that is, along the axial direction of the cell body 20, the projection of each individual tab 111 on the end face of the cell body 20 is trapezoidal.

[0040] It is understood that since the cell body 20 of this application has a cylindrical structure, one side of the projection of the tab 110 on the end face of the cell body 20 is an arc-shaped structure. Based on this, the trapezoidal structures mentioned in this application are all approximate trapezoidal structures with one side being an arc.

[0041] In this embodiment, the plurality of single-piece tabs 111 include a plurality of first single-piece tabs 1110 and a plurality of second single-piece tabs 1120. The second single-piece tabs 1120 are disposed on the side of the first single-piece tabs 1110 away from the cell body 20. The first single-piece tabs 1110 extend radially along the cell body 20. The second single-piece tabs 1120 have protrusions and extension segments 1123 extending radially along the cell body 20.

[0042] One or more first single-piece tabs 1110 are provided, and one or more second single-piece tabs 1120 are provided, wherein the first single-piece tab 1110 extends only along the radial direction of the cell body 20 and does not have a protruding structure.

[0043] Specifically, multiple second single-piece tabs 1120 are provided, and the multiple second single-piece tabs 1120 are stacked. Among the multiple second single-piece tabs 1120, the second single-piece tab 1120 adjacent to the first single-piece tab 1110 abuts against the first single-piece tab 1110. Among them, the extension segment 1123 on the protrusion and the first single-piece tab 1110 both extend radially along the cell body 20 and are stacked along the axial direction of the cell body 20.

[0044] In one specific implementation, there is one first single electrode tab 1110 and five second single electrode tabs 1120.

[0045] like Figure 2 As shown, the protrusion includes a first arm segment 1121 and a second arm segment 1122 that are bent. The first arm segment 1121 extends axially along the cell body 20, and the second arm segment 1122 is disposed between the first arm segment 1121 and the extension segment 1123.

[0046] Specifically, one end of the first arm segment 1121 is connected to the cell body 20, the other end of the first arm segment 1121 extends along the axial direction of the cell body 20 and is connected to the first end of the second arm segment 1122, the second end of the second arm segment 1122 extends toward the side of the cell body 20 and close to the axis of the cell body 20, and the second end of the second arm segment 1122 is connected to the extension segment 1123.

[0047] The first arm segment 1121 and the second arm segment 1122 are bent together to form an angular structure. The second arm segment 1122 is inclined relative to the first arm segment 1121. A support surface is formed on the side of the second arm segment 1122 away from the first arm segment 1121. The support surface is used to support the battery's busbar 30. The structure of the second arm segment 1122 supporting the busbar 30 helps to increase the contact area between the tab 110 and the busbar 30. At the same time, the second arm segment 1122 has a guiding function, making it easier for the tab 110 to be aligned with the slot structure 310 of the busbar 30 during assembly, thereby improving production efficiency.

[0048] The protrusions of multiple second single-piece tabs 1120 have the same bending angle and are fitted together. The fitted arrangement of multiple second single-piece tabs 1120 helps to ensure the strength of the tabs 110, reduce resistance, and thus improve the stability of conductivity, which is beneficial to improving the performance of the battery cell.

[0049] In this embodiment, a portion of the second single-piece tab 1120 forms a protrusion, and another portion forms an extension 1123. Due to the protruding structure of the protrusion, the distance between the radial extension 1123 of the cell body 20 and the axis of the first single-piece tab 1110 and the cell body 20 increases. It can be understood that the greater the protrusion height of the protrusion, that is, the farther away from the end face of the cell body 20 along the axial direction of the cell body 20, the greater the distance between the extension 1123 of the second single-piece tab 1120 and the axis of the cell body 20.

[0050] like Figures 1 to 3 As shown, the battery cell is formed by winding an electrode sheet 10 and a separator. The electrode sheet 10 has a plurality of single electrode tabs 111 arranged at intervals along its length. The height of the plurality of single electrode tabs 111 increases sequentially. Among two adjacent single electrode tabs 111, the single electrode tab 111 with a larger height is stacked on the side of the single electrode tab 111 with a smaller height away from the battery cell body 20.

[0051] When the electrode 10 is in the unfolded state, multiple single electrode tabs 111 are spaced apart along the length of the electrode 10. Each single electrode tab 111 is arranged in a trapezoidal structure, and each single electrode tab 111 forms a trapezoidal structure with equal base length.

[0052] In this embodiment, the spacing between the multiple single electrode tabs 111 is preset so that the multiple single electrode tabs 111 are stacked at the same position during the winding process with the electrode sheet 10.

[0053] Example 2

[0054] This embodiment provides a battery, which includes the battery cell and the busbar 30 as in Embodiment 1, with the busbar 30 disposed on the top surface of the battery cell.

[0055] like Figure 4 and Figure 5 and Figure 6 As shown, specifically, the busbar 30 is disposed on the top of the battery cell, and the busbar 30 has a groove structure 310, with at least a portion of the battery cell's tab 110 disposed inside the groove structure 310.

[0056] Since the tab 110 is located on the top of the cell body 20, the tab 110 protrudes from the cell body 20. The busbar 30 of this application adopts a groove structure 310 to cover the tab 110 and cooperate with the tab 110.

[0057] In this embodiment, multiple slot structures 310 are provided, spaced apart circumferentially along the busbar 30. Each slot structure 310 corresponds one-to-one with a tab 110, ensuring that each tab 110 has an independent slot structure 310 for adaptation. This avoids mutual interference between tabs 110 and also enhances heat dissipation. The corresponding slot structure 310 has an approximately trapezoidal structure for corresponding with the tab 110. To accommodate the tab 110, the opening of the slot structure 310 is larger than the tab 110, allowing the tab 110 to extend into the interior of the slot structure 310.

[0058] In this embodiment, the bottom surface of the slot structure 310 has a first portion that abuts against the second arm segment 1122 of the protrusion of the electrode 110 of the battery cell, and a second portion that abuts against the extension segment 1123 of the electrode 110. The first portion is formed as a sloped structure that abuts against the second arm segment 1122, and the second portion is formed as a planar structure that abuts against the extension segment 1123. The second arm segment 1122 and the extension segment 1123 abut against the bottom surface of the slot to support the busbar 30 and make full contact with the busbar 30.

[0059] Specifically, such as Figure 5 and Figure 6 As shown, the busbar 30 has a protruding structure 320 on the side away from the tab 110, and a corresponding groove structure 310 is formed on the side of the protruding structure 320 facing the tab 110. By setting the protruding structure 320, it is beneficial to increase the depth of the groove structure 310 so as to facilitate the abutment and fit between the groove structure 310 and the protruding part of the tab 110.

[0060] The arrangement structure of the busbar 30 and the battery cell in this application makes the contact between the battery cell tab 110 and the busbar 30 more compact, effectively reducing the contact resistance and improving the conductivity of the battery cell.

[0061] In this embodiment, the peripheral edge of the manifold 30 is bent toward the side away from the tab 110 so that part of the groove structure 310 is located on the bent part to form the first part of the bottom surface of the groove; at the same time, it is also beneficial to the heat conduction arrangement between the first arm segment 1121 of the protrusion and the housing after it is exposed.

[0062] In this embodiment, the battery further includes a casing and a thermally conductive adhesive. The battery cell and the busbar 30 are disposed inside the casing, and the thermally conductive adhesive is disposed between the first arm segment 1121 of the protrusion and the inner wall surface of the casing. By disposing of the thermally conductive adhesive between the first arm segment 1121 and the casing, the electrode tab 110 is insulated from the casing while the thermally conductive adhesive also has a thermally conductive effect, thus achieving the thermal conductivity between the first arm segment 1121 and the casing. In this embodiment, the first arm segment 1121 partially contacts the busbar 30 and partially contacts the casing through the thermally conductive adhesive, thereby achieving dual heat dissipation and improving the heat dissipation effect.

[0063] As can be seen from the above description, the embodiments of this application achieve the following technical effects:

[0064] This application employs multiple single-piece tabs 111 stacked along the axial direction of the cell body 20 to form tabs 110, which helps to strengthen the structural strength of the tabs 110. At the same time, the structural arrangement of multiple single-piece tabs 111 with the distance between them and the axis of the cell body 20 decreasing sequentially along the direction close to the cell body 20 avoids the possibility of the tabs 110 touching the center hole of the winding core during battery assembly or charging and discharging, thus ensuring the structural safety of the cell. In addition, the multi-layer arrangement of the tabs 110 structure in this application also ensures that the tabs 110 have good overcurrent capacity, optimizes the current distribution, and helps to improve the performance of the cell.

[0065] The tabs 110 used in this application are spaced on the cell body 20, which helps to save materials, improve installation efficiency, and thus improve battery assembly efficiency.

[0066] Obviously, the embodiments described above are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0067] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0068] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0069] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. An electric cell, characterized by, The battery cell comprises: a cell body (20); a tab (110) arranged at one end of the cell body (20) in the axial direction, the tab (110) being arranged in multiple and spaced along the circumferential direction of the cell body (20); the tab (110) is formed with a protruding portion at one end close to the circumferential edge of the cell body (20), and each tab (110) comprises a plurality of single tabs (111) stacked in the axial direction of the cell body (20), and the distance between the plurality of single tabs (111) and the axis of the cell body (20) decreases in turn in the direction close to the cell body (20).

2. The electric cell of claim 1, wherein, The plurality of single tabs (111) includes a plurality of first single tabs (1110) and a plurality of second single tabs (1120), the second single tabs (1120) are arranged on the side away from the cell body (20) of the first single tabs (1110), the first single tabs (1110) extend in the radial direction of the cell body (20), and the second single tabs (1120) have the protruding portion and an extension segment (1123) extending in the radial direction of the cell body (20).

3. The electric cell of claim 2, wherein, The protruding portion comprises a first arm segment (1121) and a second arm segment (1122) arranged by bending, one end of the first arm segment (1121) is connected with the cell body (20), the other end of the first arm segment (1121) extends in the axial direction of the cell body (20) and is connected with the first end of the second arm segment (1122), the second end of the second arm segment (1122) extends towards the side of the cell body (20) and close to the direction of the axis of the cell body (20), and the second end of the second arm segment (1122) is connected with the extension segment (1123).

4. The electric cell of claim 3, wherein, The bending angles of the protruding portions of the plurality of second single tabs (1120) are the same and are arranged in abutment.

5. The electric cell of claim 2, wherein, The first single tab (1110) is arranged in one, and the second single tab (1120) is arranged in multiple, the first single tab (1110) is stacked with the extension segment (1123) of the adjacent second single tab (1120).

6. The battery cell according to any one of claims 1 to 5, wherein at least one of the plurality of tabs (110) is a positive tab, and at least another one is a negative tab; and / or the single tab (111) is in a trapezoidal structure; and / or the projection of the tab (110) on the end surface of the cell body (20) in the axial direction of the cell body (20) is in a trapezoidal structure.

7. The electric cell of any one of claims 1 to 5, wherein, The battery cell is formed by winding the pole piece (10) and the separator, the pole piece (10) is formed with a plurality of single tabs (111) arranged at intervals in the length direction, the heights of the plurality of single tabs (111) increase in turn, and the single tab (111) with a larger height is stacked on the side away from the cell body (20) of the single tab (111) with a smaller height.

8. A battery, characterized by The battery cell comprises: the battery cell according to any one of claims 1 to 7; A busbar (30) is arranged at the top of the battery cell, and the busbar (30) is provided with a groove structure (310), and at least a part of the tab (110) of the battery cell is arranged inside the groove structure (310).

9. The battery of claim 8, wherein, A plurality of groove structures (310) are arranged along the circumference of the busbar (30), and the groove structures (310) are arranged one by one corresponding to the tabs (110).

10. The battery of claim 8, wherein, The groove bottom surface of the groove structure (310) has a first part abutting against the second arm section (1122) of the protruding part of the tab (110), and the groove bottom surface also has a second part abutting against the extension section (1123) of the tab (110).

11. The battery of claim 10, wherein, The battery further comprises: A shell, and the battery cell and the busbar (30) are arranged inside the shell; A heat-conducting adhesive is arranged between the first arm section (1121) of the protruding part and the inner wall surface of the shell.

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