Pole piece and battery cell
By setting a positioning area on the electrode tab, the electrode can be accurately positioned, which solves the problem of uneven current caused by misalignment of the positive electrode in lithium-ion batteries, reduces the risk of lithium plating and short circuit, and improves the stability of the cell.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- WEICHAI POWER CO LTD
- Filing Date
- 2025-04-09
- Publication Date
- 2026-04-21
AI Technical Summary
In lithium-ion batteries, the positive electrode is smaller than the negative electrode, and its position is difficult to observe when stacked. This can easily lead to misalignment, resulting in uneven current density, which in turn can cause lithium plating and short circuit problems.
A positioning area is set on the tab of the electrode. By aligning the positioning area on the tab, the electrode is accurately positioned, ensuring that the electrode is aligned, preventing rotation, and improving stability.
It effectively reduces the risk of lithium plating and short circuits in lithium-ion batteries, and improves the working stability of the cells.
Smart Images
Figure CN224153365U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of solid-state battery technology, and more particularly to an electrode and a battery cell. Background Technology
[0002] In existing technologies, lithium-ion batteries include positive and negative electrodes, with the positive electrode being smaller than the negative electrode. The positive electrode is often covered by the negative electrode, making it impossible to observe its position when the two electrodes are stacked, leading to potential misalignment. During pressure testing of lithium-ion batteries, this misalignment of the positive electrode can cause inconsistent current density and uneven stress within the battery, resulting in lithium plating and short circuits. Utility Model Content
[0003] In view of this, the present invention provides an electrode sheet and a battery cell. The first positioning area on the first tab of the electrode sheet enables the first sub-electrode sheet in each electrode sheet to be accurately aligned when multiple electrode sheets are stacked, thereby reducing the problems of lithium plating and short circuits in the battery cell.
[0004] In a first aspect, this utility model provides an electrode sheet, which includes a first sub-electrode sheet and a second sub-electrode sheet, the first sub-electrode sheet and the second sub-electrode sheet being stacked; the first sub-electrode sheet includes a first main body portion and at least two first electrode tabs, the at least two first electrode tabs being spaced apart and located on the same side of the first main body portion; the second sub-electrode sheet includes a second main body portion and at least two second electrode tabs, the at least two second electrode tabs being spaced apart and located on the same side of the second main body portion; along the stacking direction of the first sub-electrode sheet and the second sub-electrode sheet, the second main body portion completely covers the first main body portion; wherein: the first electrode tab is provided with a first positioning area, the first positioning area penetrating the first electrode tab along the thickness direction of the first electrode tab, the first positioning area being used to align the first sub-electrode sheets in each electrode sheet when multiple electrode sheets are stacked.
[0005] In this embodiment, when multiple electrodes are stacked, since each first sub-electrode includes a first tab and a first positioning area is provided on the first tab, the positions of the first main body portions are aligned by aligning the first positioning areas on each first tab. This ensures that the positions of the first sub-electrodes in each electrode are aligned when multiple electrodes are stacked, thereby reducing the problems of lithium plating and short circuits in the cell formed by multiple electrodes. In addition, at least two second tabs are located on the same side of the first main body portion. When aligning the first sub-electrodes through the first positioning area, rotation of the first main body portion can also be prevented, improving the stability of the alignment of the first sub-electrodes.
[0006] In one embodiment, the second electrode tab is provided with a second positioning area, which extends through the second electrode tab along its thickness direction. The second positioning area is used for the alignment of the second sub-electrode in each electrode tab when multiple electrode sheets are stacked.
[0007] In one embodiment, the first electrode tab includes a first positioning hole that penetrates the first electrode tab along its thickness direction, forming the first positioning area. The shape of the first positioning hole can be rectangular, circular, triangular, or rhomboid. When the first positioning hole is circular, the first main body may rotate when the first positioning hole on one of the first electrode tabs is aligned. Having first positioning holes on both first electrode tabs ensures the accuracy and stability of the first electrode alignment.
[0008] In one embodiment, the distance between the edge of the first positioning hole and the outer contour of the first electrode tab is greater than or equal to 4 mm.
[0009] In one embodiment, the diameter of the first positioning hole is greater than or equal to 5 mm.
[0010] In one embodiment, the first electrode tab includes a first positioning groove, the opening of which is located on the outer contour of the first electrode tab.
[0011] In one embodiment, the second electrode tab includes a second positioning hole that extends through the second electrode tab along its thickness direction, and the second positioning hole forms the second positioning area.
[0012] In one embodiment, the distance between the edge of the second positioning hole and the outer contour of the second electrode tab is greater than or equal to 4 mm.
[0013] In one embodiment, the electrode further includes an electrolyte membrane, and at least one side of the second sub-electrode is provided with the electrolyte membrane.
[0014] Secondly, this application also provides a battery cell including multiple electrodes as described in the first aspect. By using the aforementioned electrodes, the first sub-electrodes in each electrode can be aligned during the battery cell manufacturing process, which can ensure the stability of the battery cell operation. Attached Figure Description
[0015] Figure 1 A schematic diagram of the structure of an electrode sheet provided in an embodiment of this utility model;
[0016] Figure 2 A schematic diagram of another structure of the electrode provided in an embodiment of this utility model;
[0017] Figure 3A schematic diagram of another structure of the electrode provided in an embodiment of this utility model;
[0018] Figure 4 A schematic diagram of another structure of the electrode provided in an embodiment of this utility model;
[0019] Figure 5 This is another schematic diagram of the electrode sheet provided in an embodiment of the present utility model.
[0020] Icons: 10-First sub-electrode; 11-First main body; 12-First electrode tab; 120-First positioning area; 20-Second sub-electrode; 21-Second main body; 22-Second electrode tab; 220-Second positioning area. Detailed Implementation
[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0022] The electrode sheet provided in the embodiments of this utility model will be described in detail below with reference to the accompanying drawings.
[0023] Figure 1 A schematic diagram of the structure of an electrode sheet provided in an embodiment of this utility model; Figure 2 A schematic diagram of another structure of the electrode provided in an embodiment of this utility model; Figure 3 A schematic diagram of another structure of the electrode provided in an embodiment of this utility model; Figure 4 A schematic diagram of another structure of the electrode provided in an embodiment of this utility model; Figure 5 This is a schematic diagram of another structure of the electrode provided in an embodiment of the present utility model. (Refer to...) Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5The electrode provided in this application includes a first sub-electrode and a second sub-electrode. The first sub-electrode can be a positive electrode, and the second sub-electrode can be a negative electrode. The first and second sub-electrodes are stacked. The first sub-electrode includes a first main body and at least two first tabs, which are spaced apart and disposed on the same side of the first main body. The first main body and the first tabs are integrally formed. The second sub-electrode includes a second main body and at least two second tabs, which are spaced apart and disposed on the same side of the second main body. The second main body and the second tabs are integrally formed. Along the stacking direction of the first and second sub-electrodes, the second main body completely covers the first main body. The first tab has a first positioning area that penetrates the first tab along its thickness. When multiple electrodes are stacked, since each first sub-electrode includes a first tab and has a first positioning area, aligning the first positioning areas on each first tab ensures the alignment of the first main body portions, guaranteeing the alignment of the first sub-electrodes within each electrode when stacked. Furthermore, at least two second tabs are located on the same side of the first main body. When aligning the first sub-electrodes through the first positioning areas, rotation of the first main body is prevented, improving the stability of the first sub-electrode alignment. This further reduces the problems of lithium plating and short circuits in cells formed from multiple electrodes.
[0024] It is worth mentioning that, since the second main body of the second sub-electrode completely covers the first main body, when multiple electrodes are stacked, the multiple second sub-electrodes can be aligned by the edges of the multiple second main bodies, thus achieving precise alignment of the second sub-electrodes.
[0025] In the above embodiments, the first tab and the second tab can be located on the same side of the electrode or on both sides of the electrode, and can be adjusted according to actual needs.
[0026] In one embodiment, the second electrode tab is provided with a second positioning area, which extends through the second electrode tab along its thickness direction. When multiple electrode sheets are stacked, since each second sub-electrode sheet includes a second electrode tab and the second electrode tab is also provided with a second positioning area, the positions of each second main body can be aligned by aligning the second positioning areas on each second electrode tab. This ensures that the positions of the second sub-electrodes in each electrode sheet are aligned when multiple electrode sheets are stacked, and also reduces the problems of lithium plating and short circuits in the cell formed by multiple electrode sheets.
[0027] In the above embodiments, the structures of the first positioning area and the second positioning area can be the same or different, as long as they can ensure that when multiple electrodes are stacked, the first positioning area can ensure that the positions of multiple first sub-electrodes can be aligned, and the second positioning area can ensure that the positions of multiple second sub-electrodes can be aligned.
[0028] The first electrode tab may include a first positioning hole, which penetrates the first electrode tab along its thickness direction and forms the aforementioned first positioning area. When multiple electrode sheets are stacked, the alignment of the multiple first sub-electrodes can be determined as long as no other position of the first sub-electrodes can be observed through the first positioning hole. The first and second positioning holes can be circular, rectangular, triangular, or rhomboid shapes. When the first positioning hole is rectangular, triangular, or rhomboid, alignment is sufficient as long as the first positioning holes on corresponding first electrode tabs of the multiple first sub-electrodes are aligned. The shapes of the first and second electrode tabs can be conical, rectangular, or trapezoidal shapes. The following explanation uses an example where both the first and second positioning holes are rectangular, and the first electrode tab and second positioning hole are also rectangular.
[0029] The first electrode tab may include a first surface a1, a second surface b1, and a third surface c1. The first surface a1 and the third surface c1 are arranged parallel to each other, and the second surface b1 is arranged perpendicular to both the first surface a1 and the third surface c1. The distance between the first positioning hole and the first surface a1, the second surface b1, the third surface c1, and the first main body is greater than or equal to 4 mm, and the diameter of the first positioning hole is greater than 5 mm, thereby ensuring that the first electrode tab can carry a large current. Similarly, the second electrode tab may include a fourth surface a2, a fifth surface b2, and a sixth surface c2. The fourth surface a2 and the sixth surface c2 are parallel to each other, and the fifth surface b2 is arranged perpendicular to both the fourth surface a2 and the sixth surface c2. The distance between the second positioning hole and the fourth surface a2, the fifth surface b2, the sixth surface c2, and the second main body is greater than or equal to 4 mm, and the diameter of the second positioning hole is greater than 5 mm, thereby ensuring that the second electrode tab can carry a large current.
[0030] In some other embodiments, the first electrode tab may include a first positioning groove, the opening of which is located on the outer contour of the first electrode tab, and the first positioning groove may form the aforementioned first positioning area. The opening of the first positioning groove may be located on any one of the first surface a1, the second surface b1, or the third surface c1, or the opening of the first positioning groove may be located on two of the first surface a1, the second surface b1, or the third surface c1. Similarly, the second electrode tab may also include a second positioning groove, the opening of which may be located on the outer contour of the second electrode tab, and the second positioning groove may form the aforementioned second positioning area. The opening of the second positioning groove may be located on any one of the fourth surface a2, the fifth surface b2, or the sixth surface c2, or the opening of the second positioning groove may be located on two of the fourth surface a2, the fifth surface b2, or the sixth surface c2.
[0031] In the above embodiments, the first sub-electrode may include one or two first electrode tabs, and the second sub-electrode may include one or two second electrode tabs. Furthermore, the first and second electrode tabs may be located on the same side of the first or second main body, or they may be located on opposite sides of the first or second main body, depending on the specific design requirements.
[0032] The electrode may also include an electrolyte membrane disposed on at least one side of the second sub-electrode so that when the first sub-electrode and the second sub-electrode are stacked, there is no short circuit between the first sub-electrode and the second sub-electrode.
[0033] This application also provides a battery cell, which includes the electrode sheets in any of the above technical solutions. There are multiple electrode sheets stacked together. Except for the two second sub-electrodes at the first and last ends, the other second sub-electrodes are provided with electrolyte membranes on both sides to prevent short circuits between the second sub-electrodes and the first sub-electrodes.
[0034] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this utility model without departing from the spirit and scope of this utility model. Therefore, if these modifications and variations of this utility model fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.
Claims
1. A pole piece characterized by, include: The first sub-electrode and the second sub-electrode are stacked together; The first sub-electrode includes a first main body and at least two first electrode tabs, which are spaced apart and located on the same side of the first main body. The second sub-electrode includes a second main body and at least two second electrode tabs, which are spaced apart and located on the same side of the second main body. Along the stacking direction of the first and second sub-electrodes, the second main body completely covers the first main body, wherein: The first electrode tab is provided with a first positioning area, which extends through the first electrode tab along the thickness direction. The first positioning area is used to align the first sub-electrode of each electrode when multiple electrodes are stacked.
2. The pole piece of claim 1, wherein The second electrode tab is provided with a second positioning area, which extends through the second electrode tab along its thickness direction. The second positioning area is used to align the second sub-electrode in each electrode when multiple electrodes are stacked.
3. The pole piece of claim 1, wherein The first electrode tab includes a first positioning hole that extends through the first electrode tab along its thickness direction, and the first positioning hole forms the first positioning area.
4. The pole piece of claim 3, wherein The distance between the edge of the first positioning hole and the outer contour of the first electrode tab is greater than or equal to 4 mm.
5. The pole piece of claim 3 or 4, wherein The diameter of the first positioning hole is greater than or equal to 5 mm.
6. The pole piece of claim 3 or 4, wherein The shape of the first positioning hole can be one of rectangle, circle, triangle or rhombus.
7. The pole piece of claim 1, wherein The first electrode tab includes a first positioning groove, the opening of which is located on the outer contour of the first electrode tab.
8. The pole piece of claim 2, wherein The second electrode tab includes a second positioning hole that extends through the second electrode tab along its thickness direction, forming the second positioning area.
9. The pole piece of any one of claims 1 to 4, wherein The electrode further includes an electrolyte membrane, and the electrolyte membrane is disposed on at least one side of the second sub-electrode.
10. An electric cell characterized by It includes multiple electrodes as described in any one of claims 1 to 9.