Battery cell and battery
By setting through holes in the corner area of the battery cell, the problem of insufficient electrolyte wetting in the corner area of lithium-ion batteries is solved, thereby improving the wetting effect and cycle life of the battery.
Patent Information
- Application Number
- CN202422620757.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-29
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-10-29
AI Technical Summary
In the existing wound structure of lithium-ion batteries, the electrolyte wetting effect in the corner area is poor, which leads to the obstruction of lithium-ion conduction between the positive and negative electrodes in the later stage of cycling, resulting in lithium deposition at the interface, battery capacity decay and safety performance deterioration.
First and second through holes are set in the corner area of the battery cell to ensure that the electrolyte can penetrate through these holes, improve the wetting effect, and improve the lithium plating problem.
By improving the wetting effect of the electrolyte, the cycle life of the battery can be extended, the lithium plating problem in the corner area can be improved, and the battery life can be increased.
Smart Images
Figure CN223539654U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of batteries, and in particular to a battery cell and a battery. Background Technology
[0002] With the increasing prevalence of electronic products, lithium-ion batteries have become the preferred energy source for most electronic devices due to their high energy density, long cycle life, and environmental friendliness. As people spend more time and use electronic products more frequently, the requirements for battery cycle life are also increasing.
[0003] Currently, most lithium-ion batteries adopt a wound structure. For this type of battery, the wetting effect inside the core is poor. In the later stages of cycling, after the electrolyte is exhausted, the lithium-ion conduction between the positive and negative electrodes is blocked, leading to lithium deposition at the interface. This will accelerate the capacity decay of the battery and also deteriorate its safety performance. Utility Model Content
[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. It provides a battery cell and a battery that, through the arrangement of a first through hole and a second through hole, improves the electrolyte wetting effect in the corner area, alleviates the lithium plating problem in the corner area of the battery caused by insufficient electrolyte, and extends the battery life.
[0005] To achieve the above objectives, this utility model provides a battery cell having a first direction, including a first electrode, a separator, and a second electrode. The first electrode and the second electrode are spaced apart along the first direction. The separator is located between the first electrode and the second electrode in the first direction. The first electrode has a first through hole, and the second electrode has a second through hole. The orthographic projections of the first through hole and the second through hole on the separator at least partially overlap. The first electrode, the separator, and the second electrode are wound together to form a corner region, and the first through hole and the second through hole are respectively disposed in the corner region.
[0006] As a preferred embodiment, the battery cell has a second direction that intersects with the first direction, and multiple first through holes and multiple second through holes are provided, with each first through hole and each second through hole being spaced apart along the second direction.
[0007] As a preferred embodiment, the number and position of the first through hole and the second through hole are respectively set accordingly.
[0008] As a preferred embodiment, in one of the corner regions within a first electrode sheet, the number of first through holes is set to 3-5, and the diameter of the first through holes is set to 2µm-4µm;
[0009] And / or, in one of the corner regions within a second electrode, the number of second through holes is set to 3-5, and the diameter of the second through holes is set to 0.5um-1um.
[0010] As a preferred embodiment, the first through hole and the second through hole are coaxially arranged, and an impregnation channel is formed between the first through hole and the second through hole.
[0011] As a preferred embodiment, the distance between adjacent first through holes is set at 13mm-15mm.
[0012] As a preferred embodiment, the distance between adjacent second through holes is set at 13mm-15mm.
[0013] As a preferred embodiment, multiple first electrodes, multiple diaphragms, and multiple second electrodes are provided, with each diaphragm located between the first electrodes and the second electrodes that are alternately stacked along a first direction.
[0014] As a preferred embodiment, the battery cell has a planar region, the corner region is located at both ends of the planar region, the corner region includes a sloping region and an arc region, the two ends of the arc region are respectively connected to the planar region through the sloping region, and the first through hole and the second through hole are respectively disposed in the arc region.
[0015] A battery includes a casing and a battery cell, wherein the casing has a cavity for containing electrolyte, and the battery cell is connected to the cavity.
[0016] Compared with the prior art, the beneficial effects of this utility model embodiment of a battery cell and battery are as follows: the first electrode is provided with a first through hole, and the second electrode is provided with a second through hole. The electrolyte in the battery can permeate between the first electrode and the separator through the first through hole, and between the separator and the second electrode through the second through hole, thereby improving the wetting effect inside the battery. The orthogonal projections of the first through hole and the second through hole on the separator at least partially overlap, allowing the electrolyte in the battery to permeate into the battery cell along a first direction through the first through hole and the second through hole, further improving the wetting effect inside the battery cell, providing sufficient ions for charging and discharging, and improving the cycle life of the battery. Because the first electrode, separator, and second electrode are more compacted at the corner area after winding, the electrolyte in the cell can penetrate into the corner area through the first and second through holes, improving the electrolyte wetting effect at the corner area, improving the lithium plating problem in the corner area caused by insufficient electrolyte, and extending the battery life. Attached Figure Description
[0017] Figure 1This is a schematic diagram of the bending region of the battery cell in an embodiment of this utility model.
[0018] Figure 2 This is a schematic diagram of the unfolded structure of the first electrode according to an embodiment of the present invention.
[0019] Figure 3 This is a schematic diagram of the unfolded structure of the second electrode according to an embodiment of the present invention.
[0020] Figure 4 This is a schematic diagram of the structure after the first electrode, diaphragm, and second electrode are overlapped in an embodiment of this utility model.
[0021] Figure 5 This is an embodiment of the present utility model. Figure 4 A magnified structural diagram of point A in the diagram.
[0022] Figure 6 This is a schematic diagram showing the disassembled structure of the first electrode, the diaphragm, and the second electrode according to an embodiment of this utility model.
[0023] Figure 7 This is a schematic diagram of the structure of the battery cell according to an embodiment of this utility model.
[0024] In the picture:
[0025] 10. First electrode plate; 11. First through hole;
[0026] 20. Diaphragm;
[0027] 30. Second electrode plate; 31. Second through hole;
[0028] 40. Battery cell; 41. Corner area; 42. Sloping area; 43. Curved area; 44. Planar area; 45. Immersion channel;
[0029] X, the first direction; Y, the second direction. Detailed Implementation
[0030] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.
[0031] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" used to indicate the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this utility model.
[0032] In the description of this utility model, it should be understood that the terms "connected," "linked," and "fixed," etc., used in this utility model should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or a welded connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly defined. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0033] like Figures 1 to 7 As shown, a preferred embodiment of the present invention provides a battery cell with a first direction X, including a first electrode 10, a separator 20, and a second electrode 30. The first electrode 10 and the second electrode 30 are spaced apart along the first direction X. The separator 20 is located between the first electrode 10 and the second electrode 30 in the first direction X. The first electrode 10 is provided with a first through hole 11, and the second electrode 30 is provided with a second through hole 31. The orthographic projections of the first through hole 11 and the second through hole 31 on the separator 20 at least partially overlap. The first electrode 10, the separator 20, and the second electrode 30 are wound together to form a corner region 41. The first through hole 11 and the second through hole 31 are respectively provided in the corner region 41.
[0034] A battery includes a casing and a cell 40, wherein the casing has a cavity for containing electrolyte, and the cell 40 is connected to the cavity.
[0035] The battery cell and battery of this utility model have a first through hole 11 on the first electrode 10 and a second through hole 31 on the second electrode 30. The electrolyte in the battery can permeate between the first electrode 10 and the separator 20 through the first through hole 11 and between the separator 20 and the second electrode 30 through the second through hole 31, thereby improving the wetting effect inside the battery. The orthographic projections of the first through hole 11 and the second through hole 31 on the separator 20 at least partially overlap, allowing the electrolyte in the battery to permeate into the battery cell 40 along the first direction X through the first through hole 11 and the second through hole 31, further improving the wetting effect inside the battery cell 40, providing sufficient ions for charging and discharging, and improving the cycle life of the battery. Because the first electrode 10, separator 20 and second electrode 30 are relatively compacted in the corner area 41 after winding, the electrolyte in the cell 40 can penetrate into the corner area 41 through the first through hole 11 and the second through hole 31, thereby improving the electrolyte wetting effect in the corner area 41, improving the lithium plating problem in the corner area 41 caused by insufficient electrolyte, and improving the battery life.
[0036] Among them, such as Figure 1 as well as Figure 6 As shown, the first electrode 10 and the second electrode 30 serve to provide carriers for electron conduction and ion channels, while also facilitating electrochemical reactions during electrode reactions. The separator 20 is located between the first electrode 10 and the second electrode 30 in the first direction X. The separator 20 isolates the first electrode 10 from the second electrode 30 and prevents electrons from freely passing through, while allowing ions in the electrolyte to freely pass between the first electrode 10, the separator 20, and the second electrode 30. If the first electrode 10 is the positive electrode, then the second electrode 30 is the negative electrode; or if the first electrode 10 is the negative electrode, then the second electrode 30 is the positive electrode.
[0037] Furthermore, such as Figures 1 to 4 As shown, the battery cell 40 has a second direction Y, which intersects with the first direction X. Multiple first through holes 11 and second through holes 31 are respectively provided, with each first through hole 11 and each second through hole 31 spaced apart along the second direction Y. The multiple first through holes 11 spaced apart along the second direction Y increase the number of first through holes 11 and shorten the distance between adjacent first through holes 11 in the second direction Y. This allows the electrolyte to quickly penetrate the outer periphery of adjacent first through holes 11 in the second direction Y after entering between the first electrode 10 and the separator 20 through the first through holes 11, making it easier for the first electrode 10 and the separator 20 to achieve complete penetration. Multiple second through holes 31 are spaced apart along the second direction Y. Increasing the number of second through holes 31 in the second direction Y shortens the distance between two adjacent second through holes 31 in the second direction Y. This allows the electrolyte to quickly penetrate the outer periphery of adjacent second through holes 31 in the second direction Y after entering between the second electrode 30 and the diaphragm 20 through the second through holes 31, making it easier for the second electrode 30 and the diaphragm 20 to achieve full penetration.
[0038] Furthermore, such as Figures 1 to 2 as well as Figure 4 As shown, in one of the corner regions 41 within a first electrode 10, the number of first through holes 11 is set to 3-5, and the diameter of the first through holes 11 is set to 2um-4um; or, as Figure 1 as well as Figures 3 to 4 As shown, in one of the corner regions 41 within a second electrode 30, the number of second through holes 31 is set to 3-5, and the diameter of the second through holes 31 is set to 0.5um-1um. By setting the number of first through holes 11 and second through holes 31 within an appropriate range, the wetting effect on the battery cell 40 is ensured. At the same time, by setting the diameter of the first through holes 11 and second through holes 31 within a set range, the number of first through holes 11 in the first electrode 10 and the number of second through holes 31 in the second electrode 30 are controlled, thus ensuring the support strength of the first electrode 10 and the second electrode 30.
[0039] Furthermore, when the first through-hole 11 and the second through-hole 31 are set independently, the smooth wetting effect of the electrolyte is difficult to fully demonstrate, such as... Figure 1 as well as Figure 4 As shown, the number and position of the first through hole 11 and the second through hole 31 are respectively set so that a wetting channel 45 is formed between the first through hole 11 and the second through hole 31, so that the electrolyte can enter the corner area 41 and the inside of the battery cell 40 more smoothly from the wetting channel 45, give full play to the role of the wetting channel 45, and improve the wetting efficiency of the electrolyte.
[0040] Furthermore, such as Figure 2 As shown, the distance between adjacent first through holes 11 is set at 13mm-15mm to ensure the support strength of the first electrode 10 and prevent the first electrode 10 from breaking when it expands.
[0041] Furthermore, such as Figure 3 As shown, the distance between adjacent second through holes 31 is set at 13mm-15mm to ensure the support strength of the second electrode 30 and prevent the first electrode 10 from breaking when it expands.
[0042] Furthermore, such as Figure 1 as well as Figure 4 As shown, the first through hole 11 and the second through hole 31 are coaxially arranged, and a wetting channel 45 is formed between the first through hole 11 and the second through hole 31. The coaxial arrangement of the first through hole 11 and the second through hole 31 increases the overlap area of the first through hole 11 and the second through hole 31, making it easier for the electrolyte to enter the corner area 41 and the inside of the battery cell 40 from the wetting channel 45, thereby improving the wetting efficiency of the electrolyte.
[0043] Furthermore, such as Figure 1 As shown, multiple first electrode plates 10, separators 20, and second electrode plates 30 are respectively provided, with each separator 20 located between the alternating layers of first electrode plates 10 and second electrode plates 30 along the first direction X. Multiple first electrode plates 10, separators 20, and second electrode plates 30 are wound to form a battery cell 40. The first electrode plates 10 and second electrode plates 30, spaced apart along the first direction X from the battery cell 40, are respectively provided with first through holes 11 and second through holes 31. This allows electrolyte to permeate into the battery cell 40 through the wetting channel 45 formed between the first through holes 11 and the second through holes 31, maintaining the electrolyte level within a set range. In the later stages of cycling, sufficient ions can be provided for charging and discharging, improving the battery's cycle life. This also prevents overcharging during charging due to insufficient electrolyte level, which could lead to a rapid increase in electrolyte and cause electrolyte swelling.
[0044] Furthermore, such as Figure 7As shown, the battery cell 40 has a planar region 44, and corner regions 41 are located at both ends of the planar region 44. The corner region 41 includes a sloped region 42 and an arc-shaped region 43. The two ends of the arc-shaped region 43 are connected to the planar region 44 through the sloped region 42, respectively. The first through hole 11 and the second through hole 31 are respectively set in the arc-shaped region 43. The arc-shaped region 43 is connected to the planar region 44 through the sloped region 42, and the shape gradually transitions. The arc-shaped region 43 is the location with greater compaction strength in the corner region 41. The first through hole 11 and the second through hole 31 are only set in the arc-shaped region 43. When electrolyte is injected, the electrolyte will enter the corner region 41 and the battery interior through the first through hole 11 and the second through hole 31, better wetting the separator 20, the first electrode 10 and the second electrode 30, ensuring electrolyte retention. In the later stages of cycling, there is enough electrolyte to conduct ions, preventing lithium deposition at the interface of the corner region 41 and the end, and improving the cycle life of the battery. At the same time, it ensures the support strength within the cell 40, avoids the occupation of the reaction area of the first electrode 10 and the second electrode 30, and ensures that the first electrode 10 and the second electrode 30 provide sufficient active material to contact the electrolyte, thereby accelerating the charge and ion transfer rate and ensuring the rate and efficiency of the battery's electrochemical reaction.
[0045] In summary, this utility model embodiment provides a battery cell and a battery. The first electrode 10 is provided with a first through hole 11, and the second electrode 30 is provided with a second through hole 31. The electrolyte in the battery can permeate between the first electrode 10 and the separator 20 through the first through hole 11, and between the separator 20 and the second electrode 30 through the second through hole 31, thereby improving the wetting effect inside the battery. The orthographic projections of the first through hole 11 and the second through hole 31 on the separator 20 at least partially overlap, allowing the electrolyte in the battery to permeate into the battery cell 40 along the first direction X through the first through hole 11 and the second through hole 31, further improving the wetting effect inside the battery cell 40, providing sufficient ions for charging and discharging, and improving the cycle life of the battery. Because the first electrode 10, separator 20 and second electrode 30 are relatively compacted in the corner area 41 after winding, the electrolyte in the cell 40 can penetrate into the corner area 41 through the first through hole 11 and the second through hole 31, thereby improving the electrolyte wetting effect in the corner area 41, improving the lithium plating problem in the corner area 41 caused by insufficient electrolyte, and improving the battery life.
[0046] The above are merely preferred embodiments of this utility model. It should be noted that, for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of this utility model, and these improvements and substitutions should also be considered within the protection scope of this utility model.
Claims
1. A battery cell having a first orientation, characterized in that: The device includes a first electrode, a diaphragm, and a second electrode. The first electrode and the second electrode are spaced apart along a first direction. The diaphragm is located between the first electrode and the second electrode in the first direction. The first electrode has a first through hole, and the second electrode has a second through hole. The orthographic projections of the first through hole and the second through hole on the diaphragm at least partially overlap. The first electrode, the diaphragm, and the second electrode are wound together to form a corner region. The first through hole and the second through hole are respectively disposed in the corner region.
2. The battery cell according to claim 1, characterized in that: The battery cell has a second direction that intersects with the first direction. Multiple first through holes and multiple second through holes are provided, and each first through hole and each second through hole is spaced apart along the second direction.
3. The battery cell according to claim 2, characterized in that: The number and position of the first through hole and the second through hole are respectively set.
4. The battery cell according to claim 1, characterized in that: In one of the corner regions within a first electrode, the number of first through holes is set to 3-5, and the diameter of the first through holes is set to 2µm-4µm; And / or, in one of the corner regions within a second electrode, the number of second through holes is set to 3-5, and the diameter of the second through holes is set to 0.5um-1um.
5. The battery cell according to claim 1, characterized in that: The first through hole and the second through hole are coaxially arranged, and an impregnation channel is formed between the first through hole and the second through hole.
6. The battery cell according to claim 1, characterized in that: The distance between adjacent first through holes is set at 13mm-15mm.
7. The battery cell according to claim 1, characterized in that: The distance between adjacent second through holes is set at 13mm-15mm.
8. The battery cell according to claim 1, characterized in that: The first electrode, the diaphragm, and the second electrode are each provided in multiples, and each diaphragm is located between the first electrode and the second electrode that are alternately stacked along the first direction.
9. The battery cell according to claim 1, characterized in that: The battery cell has a planar region, and the corner region is located at both ends of the planar region. The corner region includes a sloping region and an arc region. The two ends of the arc region are respectively connected to the planar region through the sloping region. The first through hole and the second through hole are respectively disposed in the arc region.
10. A battery, characterized in that: The device includes a housing and a battery cell as described in any one of claims 1-9, wherein the housing has a cavity for containing electrolyte, and the battery cell is connected to the cavity.