Pole piece, battery cell and battery
By setting a bending section on the tab of the composite foil, an electrical connection is formed between the conductive layers, which solves the problem that the conductive layers on both sides of the composite foil cannot conduct electricity effectively, thus improving the energy density and safety performance of lithium-ion batteries.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHENZHEN HIGHPOWER TECH CO LTD
- Filing Date
- 2025-05-14
- Publication Date
- 2026-04-28
AI Technical Summary
The conductive layers on both sides of the composite foil cannot conduct electricity effectively, affecting the energy density and safety performance of lithium-ion batteries.
A bending section is provided on the tab of the composite foil material, and a bending piece is formed by the portion of the conductive layer peeled off from the conductive layer on both sides of the substrate layer, so as to realize the electrical connection on both sides of the tab of the composite foil material.
This technology enables effective conductivity of the conductive layers on both sides of the composite foil tab, thereby improving the energy density and safety performance of lithium-ion batteries.
Smart Images
Figure CN224177320U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of battery technology, and in particular to an electrode, a battery cell, and a battery. Background Technology
[0002] In the new energy consumer market, lithium-ion batteries have rapidly occupied the 3C digital consumer market, the new energy vehicle market, and the energy storage application market due to their high energy density. With the development of the industry, the requirements for the electrical energy stored per unit mass of lithium-ion batteries are also getting higher and higher, that is, the requirements for the energy density of batteries are getting higher and higher.
[0003] To improve the energy density of lithium-ion batteries, composite foils are often used instead of traditional metal foils. Composite foils have a lower areal density, which reduces the weight of the current collector and thus increases the battery's energy density. On the other hand, because polymer materials have high ductility, when a lithium-ion battery is impacted by a foreign object, the polymer material can wrap around the fracture surface, thus preventing the fracture from piercing the separator and causing a short circuit, reducing the risk of thermal runaway and improving the safety performance of the lithium-ion battery. However, due to the low conductivity of polymer materials, effective conductivity cannot be achieved between the conductive layers on both sides of the polymer material. Utility Model Content
[0004] This utility model provides an electrode sheet to solve the problem in related technologies where the conductive layers on both sides of the composite foil cannot effectively conduct electricity, thereby enabling the conductive layers on both sides of the composite foil to effectively conduct electricity.
[0005] The electrode sheet of this utility model embodiment includes a composite foil electrode tab, which includes a substrate layer and conductive layers located on both sides of the substrate layer.
[0006] The composite foil tab is provided with a bending portion, which includes two bent pieces formed by portions of conductive layers peeled off from the conductive layers located on both sides of the substrate layer.
[0007] The electrode sheet of this utility model embodiment has a bent portion on the composite foil electrode tab, which includes two bent portions formed by the partial conductive layers peeled off from the conductive layers on both sides of the substrate layer. This enables electrical connection between the conductive layers on both sides of the composite foil electrode tab, thereby enabling effective conduction between the conductive layers on both sides of the composite foil electrode tab, and further enabling effective conduction between the conductive layers on both sides of the composite foil.
[0008] In some embodiments, the bent sheet is centrally disposed in the width direction of the composite foil tab.
[0009] In some embodiments, the bent sheet is a strip-shaped sheet extending along the length direction of the composite foil tab.
[0010] In some embodiments, the bent piece is rectangular.
[0011] In some embodiments, the ratio between the width of the bent sheet and the width of the composite foil tab is 0.1-0.5.
[0012] In some embodiments, the bent sheet and the composite foil tab have an overlapping region in the thickness direction of the composite foil tab, and the ratio between the dimension of the overlapping region in the length direction of the composite foil tab and the length of the composite foil tab is 0.1-0.4.
[0013] In some embodiments, the bent sheet has a protrusion that extends beyond the side edge of the composite foil tab.
[0014] In some embodiments, the ratio between the dimension of the protrusion in the length direction of the composite foil tab and the length of the bent sheet is 1 / 3 to 8 / 9.
[0015] This utility model also provides a battery cell.
[0016] The battery cell of this utility model embodiment includes the electrode sheet as described in the above embodiment, wherein the composite foil electrode tab is a single piece, and the bent piece of the single composite foil electrode tab is electrically connected; or the composite foil electrode tab is a plurality of pieces, wherein the plurality of composite foil electrode tabs are arranged sequentially in the thickness direction of the battery cell, and the bent pieces of the plurality of composite foil electrode tabs are electrically connected.
[0017] By providing the electrode plates as described in the above embodiments, the battery cell of this utility model can form an effective electrical connection between the conductive layers on both sides of the composite foil of the battery cell, that is, it can enable effective conductivity between the conductive layers on both sides of the composite foil of the battery cell.
[0018] This utility model also provides a battery.
[0019] The battery of this utility model embodiment includes the battery cell described in the above embodiment. Attached Figure Description
[0020] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0021] Figure 1 This is one of the structural schematic diagrams of the electrode sheet in an embodiment of this utility model;
[0022] Figure 2 This is an enlarged view of the composite foil electrode tab of the electrode sheet in an embodiment of this utility model.
[0023] In the picture:
[0024] 100. Electrode;
[0025] 1. Composite foil tabs;
[0026] 101. Bending section; 1011. Bending piece; 10111. Protrusion;
[0027] 2. Overlapping areas. Detailed Implementation
[0028] To make the technical problems solved, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.
[0029] In the description of this utility model, it should be understood that the terms "longitudinal," "radial," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0030] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal encapsulation of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0031] In order to solve the problem that the conductive layers on both sides of the composite foil in the related technology cannot effectively conduct electricity, this utility model provides an electrode 100.
[0032] The electrode 100 of this utility model embodiment includes a composite foil electrode tab 1, which includes a substrate layer and conductive layers located on both sides of the substrate layer. The composite foil electrode tab 1 is provided with a bending portion 101, which includes two bent pieces 1011 formed by portions of conductive layers peeled off from the conductive layers located on both sides of the substrate layer.
[0033] The electrode 100 of this utility model embodiment has a bent portion 101 on the composite foil electrode tab 1, which includes two bent portions 1011 formed by the partial conductive layers peeled off from the conductive layers on both sides of the substrate layer. This enables the conductive layers on both sides of the composite foil electrode tab 1 to be electrically connected, thereby enabling effective conduction between the conductive layers on both sides of the composite foil electrode tab 1, and further enabling effective conduction between the conductive layers on both sides of the composite foil.
[0034] The following is in conjunction with the appendix Figures 1-2 The electrode 100 of this utility model embodiment is described below.
[0035] like Figure 1 As shown, the electrode 100 of this utility model embodiment includes a composite foil electrode tab 1, which includes a substrate layer and conductive layers located on both sides of the substrate layer.
[0036] The composite foil tab 1 is provided with a bending portion 101, which includes two bent pieces 1011 formed by portions of conductive layers peeled off from the conductive layers located on both sides of the substrate layer.
[0037] It is understandable that the exposed portions of the conductive layers on both sides of the substrate layer can be connected, enabling the conductive layers on both sides of the substrate layer to conduct electricity effectively, thereby enabling effective conductivity between the conductive layers on both sides of the composite foil.
[0038] In some embodiments, the bent piece 1011 is centered in the width direction of the composite foil tab 1.
[0039] The electrode 100 of this utility model embodiment can greatly reduce the processing difficulty of the bending sheet 1011 by centrally positioning the bending sheet 1011 in the width direction of the composite foil electrode tab 1.
[0040] In some embodiments, the bent sheet 1011 is a strip-shaped sheet extending along the length direction of the composite foil tab 1.
[0041] Preferably, the bent piece 1011 is rectangular.
[0042] The electrode 100 of this utility model embodiment can greatly reduce the processing difficulty of the bent sheet 1011 by setting the shape of the bent sheet 1011 to a rectangle.
[0043] Furthermore, the ratio between the width of the bent piece 1011 and the width of the composite foil tab 1 is 0.1-0.5.
[0044] In other words, the ratio between the dimension of the bent piece 1011 in the width direction of the composite foil tab 1 and the dimension of the composite foil tab 1 in the width direction is 0.1-0.5.
[0045] It is understandable that when the ratio between the dimension of the bent piece 1011 in the width direction of the composite foil tab 1 and the dimension of the composite foil tab 1 in its width direction is too low, it means that the dimension of the bent piece 1011 in the width direction of the composite foil tab 1 is too small, which will result in the current carrying capacity of the bent piece 1011 being too low.
[0046] When the ratio between the dimension of the bent piece 1011 in the width direction of the composite foil tab 1 and the dimension of the composite foil tab 1 in the width direction is too high, it means that after the conductive layer of the composite foil tab 1 is partially peeled off, the remaining conductive layer of the composite foil tab 1 has a too low dimension in the width direction. This will also result in a low current carrying capacity of the composite foil tab 1 and affect the structural strength of the composite foil tab 1.
[0047] Therefore, the inventors discovered through research that when the ratio between the dimension of the bent piece 1011 in the width direction of the composite foil tab 1 and the dimension of the composite foil tab 1 in its width direction is set to 0.1-0.5, the overall current carrying capacity of the composite foil tab 1 can be guaranteed while ensuring that the composite foil tab 1 has qualified structural strength.
[0048] In some embodiments, such as Figure 2 As shown, the bent sheet 1011 and the composite foil tab 1 have an overlapping region 2 in the thickness direction of the composite foil tab 1. The ratio between the dimension of the overlapping region 2 in the length direction of the composite foil tab 1 and the length of the composite foil tab 1 is 0.1-0.4.
[0049] It is understandable that the overlapping region 2 is essentially the connection area between the bent piece 1011 and the remaining conductive layer. The ratio between the dimension of the overlapping region 2 in the length direction of the composite foil tab 1 and the length of the composite foil tab 1 affects the size of the overlapping region 2, and thus affects the current carrying capacity of the composite foil tab 1. If the ratio between the dimension of the overlapping region 2 in the length direction of the composite foil tab 1 and the length of the composite foil tab 1 is too small, the current carrying capacity of the composite foil tab 1 will be reduced.
[0050] If the ratio between the dimension of the overlapping region 2 in the length direction of the composite foil tab 1 and the length of the composite foil tab 1 is too large, it means that the remaining area of the conductive layer is too small, which will reduce the structural strength of the composite foil tab 1.
[0051] Therefore, the inventors set the ratio between the dimension of the overlapping region 2 in the length direction of the composite foil tab 1 and the length of the composite foil tab 1 to 0.1-0.4, which can improve the current carrying capacity of the composite foil tab 1 while ensuring that the structural strength of the composite foil tab 1 meets the requirements.
[0052] In some embodiments, the bent sheet 1011 has a protrusion 10111 that protrudes from the side edge of the composite foil tab 1.
[0053] Furthermore, the ratio between the dimension of the protrusion 10111 in the length direction of the composite foil tab 1 and the length of the bent piece 1011 is 1 / 3 to 8 / 9.
[0054] In other words, the ratio between the dimension of the protrusion 10111 in the length direction of the composite foil tab 1 and the dimension of the bent piece 1011 in the length direction of the composite foil tab 1 is 1 / 3 to 8 / 9.
[0055] By setting the ratio between the dimension of the protrusion 10111 in the length direction of the composite foil tab 1 and the dimension of the bent piece 1011 in the length direction of the composite foil tab 1 to 1 / 3-8 / 9, it is possible to ensure that the two bent pieces 1011 of the bent portion 101 can form an effective connection, thereby achieving the effect of electrically connecting the conductive layers on both sides of the composite foil.
[0056] This utility model also provides a battery cell.
[0057] The battery cell of this utility model embodiment includes the electrode 100 as described in the above embodiment.
[0058] It is understood that a battery cell typically includes a positive electrode 100 and a negative electrode 100. That is, in the battery cell of this utility model embodiment, at least one of the positive electrode 100 and the negative electrode 100 is the electrode 100 described in the above embodiment. It is possible that the positive electrode 100 is the electrode 100 described in the above embodiment, the negative electrode 100 is the electrode 100 described in the above embodiment, or both the positive electrode 100 and the negative electrode 100 are the electrode 100 described in the above embodiment.
[0059] Optionally, the composite foil tab 1 is a single piece, and the bent piece 1011 of the single composite foil tab 1 is electrically connected. Specifically, the protrusion 10111 of the bent piece 1011 of the single composite foil tab 1 is electrically connected.
[0060] Optionally, there are multiple composite foil tabs 1, which are arranged sequentially in the thickness direction of the battery cell. The bending pieces 1011 of the multiple composite foil tabs 1 are electrically connected. Specifically, the protrusions 10111 of the bending pieces 1011 of the multiple composite foil tabs 1 are electrically connected.
[0061] By providing the electrode 100 as described in the above embodiment, the battery cell of this utility model can form an effective electrical connection between the conductive layers on both sides of the composite foil of the battery cell, that is, it can enable effective conductivity between the conductive layers on both sides of the composite foil of the battery cell.
[0062] This utility model also provides a battery.
[0063] The battery of this utility model embodiment includes the battery cell described in the above embodiment.
[0064] The above-described embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model, and should all be included within the protection scope of this utility model.
Claims
1. An electrode sheet, characterized in that, The composite foil tab (1) includes a substrate layer and conductive layers located on both sides of the substrate layer. The composite foil tab (1) is provided with a bending portion (101), the bending portion (101) includes two bent pieces (1011) formed by the partial conductive layers peeled off from the conductive layers located on both sides of the substrate layer.
2. The electrode sheet according to claim 1, characterized in that, The bent piece (1011) is centered in the width direction of the composite foil tab (1).
3. The electrode sheet according to claim 1, characterized in that, The bent sheet (1011) is a strip-shaped sheet extending along the length direction of the composite foil tab (1).
4. The electrode sheet according to claim 1, characterized in that, The bent piece (1011) is rectangular.
5. The electrode sheet according to claim 1, characterized in that, The ratio between the width of the bent piece (1011) and the width of the composite foil tab (1) is 0.1-0.
5.
6. The electrode sheet according to claim 1, characterized in that, The bent sheet (1011) and the composite foil tab (1) have an overlapping area (2) in the thickness direction of the composite foil tab (1), and the ratio between the size of the overlapping area (2) in the length direction of the composite foil tab (1) and the length of the composite foil tab (1) is 0.1-0.
4.
7. The electrode sheet according to claim 1, characterized in that, The bent piece (1011) has a protrusion (10111) that protrudes from the side edge of the composite foil tab (1).
8. The electrode sheet according to claim 7, characterized in that, The ratio between the dimension of the protrusion (10111) in the length direction of the composite foil tab (1) and the length of the bent piece (1011) is 1 / 3 to 8 / 9.
9. A battery cell, characterized in that, The battery cell includes an electrode (100) as described in any one of claims 1-8, wherein the composite foil tab (1) is a single one, and the bent piece (1011) of the single composite foil tab (1) is electrically connected; or the composite foil tab (1) is a plurality of ones, wherein the plurality of composite foil tabs (1) are arranged sequentially in the thickness direction of the battery cell, and the bent pieces (1011) of the plurality of composite foil tabs (1) are electrically connected.
10. A battery, characterized in that, Including the battery cell as described in claim 9.