Battery cell, battery and electric equipment
By setting an isolation layer on the extended part of the negative electrode of the pouch cell and setting etched areas on both sides of the positive electrode, the problem of head and tail deformation of the cell during long-term cycling is solved, thus improving the stability and lifespan of the cell.
Patent Information
- Application Number
- CN202423198760.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-24
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2034-12-24
AI Technical Summary
In long-term cycling, the negative electrode of a pouch cell is prone to lithium plating beyond the positive electrode, which can cause deformation at the head and tail of the cell.
An isolation layer is set on the part of the negative electrode that extends beyond the positive electrode to block electron conduction, and etched areas are set on both sides of the positive electrode to reduce the density of active material, suppress lithium ion aggregation, and prevent the negative electrode from deforming.
This effectively avoids the deformation of the head and tail of the battery cell during long-term cycling, improving the stability and lifespan of the battery cell.
Smart Images
Figure CN223828556U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of battery technology, and particularly relates to battery cells, batteries and electrical equipment. Background Technology
[0002] In the winding direction perpendicular to the core of the pouch cell, the size of the negative electrode sheet of the pouch cell is usually larger than that of the positive electrode sheet, and the side edge of the negative electrode sheet extends beyond the side edge of the positive electrode sheet.
[0003] However, during long-term cycling, this cell structure is prone to lithium plating when the negative electrode extends beyond the positive electrode. This can cause deformation of the negative electrode beyond the positive electrode, leading to deformation at the head and tail of the cell. Utility Model Content
[0004] To address the problem of head and tail deformation in battery cells during long-term cycling in related technologies, this utility model provides a battery cell.
[0005] The battery cell of this utility model embodiment includes a positive electrode sheet, a negative electrode sheet and a separator, wherein the positive electrode sheet, the separator and the negative electrode sheet are stacked and wound along the winding direction to form the battery cell;
[0006] Along the length of the battery cell, the negative electrode has a first protruding area extending beyond the positive electrode, and the separator has a second protruding area extending beyond the positive electrode.
[0007] The second protruding area is provided with an isolation layer corresponding to the first protruding area, and the isolation layer is supported between the first protruding area and the second protruding area.
[0008] The battery cell of this utility model provides an isolation layer between the first protruding area and the second protruding area, which can block the electronic conduction between the first protruding area of the negative electrode and the positive electrode. This makes it difficult for the active material in the first protruding area to participate in charging and discharging, and thus it is difficult for the active material in this part to effectively release or absorb lithium ions. This can effectively avoid the problem of lithium plating in the first protruding area of the negative electrode, thereby avoiding the problem of head and tail deformation of the battery cell during long-term cycling.
[0009] Therefore, the battery cell of this embodiment can avoid the problem of head and tail deformation during long-term cycling.
[0010] In some embodiments, the insulating layer is a PP adhesive layer or a rubber layer.
[0011] In some embodiments, the thickness of the isolation layer is 1-5 μm.
[0012] In some embodiments, in the first direction, etched regions are provided on both sides of the positive electrode sheet.
[0013] In some embodiments, the size of the etched area in the first direction is 1-2 mm.
[0014] In some embodiments, the etching region has a plurality of etching grooves spaced apart along the length of the positive electrode sheet.
[0015] In some embodiments, the spacing between adjacent etching grooves is 0.3~1.5 mm;
[0016] The dimension of the etching groove in the first direction is 1-2 mm;
[0017] The depth of the etching groove is 10-90% of the thickness of the active material layer located on one side of the positive electrode.
[0018] In some embodiments, in the first direction, the dimensions of both the first protruding area and the second protruding area are 0.3-1.5 mm.
[0019] This utility model also provides a battery, including the battery cell as described in the above embodiments.
[0020] This utility model also provides an electrical device, including the battery described in the above embodiments. Attached Figure Description
[0021] 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.
[0022] Figure 1 This is one of the structural schematic diagrams of the battery cell according to an embodiment of this utility model;
[0023] Figure 2 This is the second schematic diagram of the battery cell structure according to an embodiment of this utility model.
[0024] In the picture:
[0025] 1. Positive electrode plate;
[0026] 2. Negative electrode; 201. First protruding area;
[0027] 3. Diaphragm; 301. Second protruding area;
[0028] 4. Isolation layer;
[0029] 5. Etched area;
[0030] 6. Etching grooves;
[0031] 7. Extreme ear. Detailed Implementation
[0032] 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.
[0033] 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.
[0034] 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.
[0035] The following is in conjunction with the appendix Figure 1-2 This invention describes the battery cell of an embodiment of the present invention.
[0036] The battery cell of this utility model embodiment includes a positive electrode 1, a negative electrode 2 and a separator 3. The positive electrode 1, the separator 3 and the negative electrode 2 are stacked and wound along the winding direction to form a battery cell.
[0037] like Figure 1 As shown, the head of the battery cell is the end with tabs 7, and the tail of the battery cell is the end without tabs 7.
[0038] In a first direction perpendicular to the winding direction, the negative electrode 2 has a first protruding region 201 that extends beyond the positive electrode 1, and the separator 3 has a second protruding region 301 that extends beyond the positive electrode 1.
[0039] Specifically, such as Figure 1-2As shown, the first direction perpendicular to the winding direction in this embodiment is the length direction of the negative electrode 2, the positive electrode 1, and the separator 3.
[0040] An isolation layer 4 is provided on the second protruding area 301 corresponding to the first protruding area 201. In other words, the isolation layer 4 covers the area of the second protruding area 301 corresponding to the first protruding area 201, and the isolation layer 4 is supported between the first protruding area 201 and the second protruding area 301.
[0041] The battery cell of this utility model provides an isolation layer 4 between the first protruding area 201 and the negative electrode 2 by setting an isolation layer 4 in the second protruding area 301. This can block the electronic conduction between the first protruding area 201 of the negative electrode 2 and the positive electrode 1, making it difficult for the active material in the first protruding area 201 to participate in charging and discharging. Consequently, the active material in this part is difficult to effectively release or absorb lithium ions, thus effectively avoiding the problem of lithium plating in the first protruding area 201 of the negative electrode 2. This can prevent the battery cell from deforming at the head and tail during long-term cycling.
[0042] Therefore, the battery cell of this embodiment can avoid the problem of head and tail deformation during long-term cycling.
[0043] In some embodiments, the isolation layer 4 is a PP adhesive layer or a rubber layer. In practical applications, both the PP adhesive layer and the rubber layer can be formed by coating.
[0044] Preferably, the thickness of the isolation layer 4 is 1-5 μm.
[0045] In some embodiments, in the first direction, etched regions 5 are provided on both sides of the positive electrode 1.
[0046] The battery cell of this utility model can reduce the density of active material on the positive electrode 1 by setting etching regions 5 on both sides of the positive electrode 1, thereby increasing the CB value, suppressing the accumulation of lithium ions in the first protrusion region 201 of the negative electrode 2, and further avoiding the problem of deformation of the first protrusion region 201 of the negative electrode 2 during long-term cycling.
[0047] Preferably, in the first direction, the size of the etched area 5 is 1-2 mm.
[0048] Preferably, the etching region 5 is provided with a plurality of etching grooves 6 spaced apart along the length direction of the positive electrode 1.
[0049] Preferably, the spacing between adjacent etching grooves 6 is 0.3~1.5mm;
[0050] The dimension of the etching groove 6 in the first direction is 1-2 mm;
[0051] The depth of the etching trench 6 is 10-90% of the thickness of the active material layer on one side of the positive electrode 1.
[0052] In some embodiments, the size of the first protrusion region 201 in the first direction is 0.3-1.5 mm;
[0053] Along the length of the cell, the second protruding region 301 has a size of 0.3-1.5 mm.
[0054] like Figure 1 As shown, the size of the second protruding area 301 is larger than the size of the first protruding area 201. Therefore, when setting the isolation layer 4, it is only necessary to set it in the area of the second protruding area 301 corresponding to the first protruding area 201. That is, the area of the isolation layer 4 is the same as the area of the first protruding area 201. This can further prevent electronic conduction between the first protruding area 201 of the negative electrode 2 and the positive electrode 1, making it difficult for the active material of the first protruding area 201 to participate in charging and discharging. Consequently, the active material in this part is difficult to effectively release or absorb lithium ions, thus effectively preventing the problem of lithium plating in the first protruding area 201 of the negative electrode 2. This can prevent the problem of head and tail deformation of the cell during long-term cycling, and thus prevent the problem of head and tail deformation of the battery during long-term cycling.
[0055] This utility model also provides a battery, including the battery cell of the above embodiment.
[0056] The battery of this utility model embodiment can avoid the problem of head and tail deformation during long-term cycling by setting the battery cell of the above embodiment.
[0057] Therefore, the battery of this utility model embodiment can avoid the problem of head and tail deformation during long-term cycling.
[0058] This utility model also provides an electrical device, including the battery described in the above embodiments.
[0059] 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. A battery cell, characterized in that, The battery cell includes a positive electrode (1), a negative electrode (2), and a separator (3), wherein the positive electrode (1), the separator (3), and the negative electrode (2) are stacked and wound along the winding direction to form the battery cell; In a first direction perpendicular to the winding direction, the negative electrode (2) has a first protruding area (201) extending beyond the positive electrode (1), and the diaphragm (3) has a second protruding area (301) extending beyond the positive electrode (1). The second protruding area (301) is provided with an isolation layer (4) corresponding to the first protruding area (201), and the isolation layer (4) is supported between the first protruding area (201) and the second protruding area (301).
2. The battery cell according to claim 1, characterized in that, The isolation layer (4) is a PP adhesive layer or a rubber layer.
3. The battery cell according to claim 1, characterized in that, The thickness of the isolation layer (4) is 1-5 μm.
4. The battery cell according to claim 1, characterized in that, In the first direction, the positive electrode (1) has etched areas (5) on both sides of its edge.
5. The battery cell according to claim 4, characterized in that, In the first direction, the size of the etched area (5) is 1-2 mm.
6. The battery cell according to claim 4, characterized in that, The etching area (5) is provided with a plurality of etching grooves (6) spaced apart along the length direction of the positive electrode (1).
7. The battery cell according to claim 6, characterized in that, The spacing between adjacent etching grooves (6) is 0.3~1.5mm; The etching groove (6) has a dimension of 1-2 mm in the first direction; The depth of the etching groove (6) is 10-90% of the thickness of the active material layer on one side of the positive electrode (1).
8. The battery cell according to claim 1, characterized in that, In the first direction, the dimensions of the first protruding area (201) and the second protruding area (301) are both 0.3-1.5 mm.
9. A battery, characterized in that, Including the battery cell as described in any one of claims 1-8.
10. An electrical appliance, characterized in that, Includes the battery as described in claim 9.