电池单体、电池装置和用电装置
By designing the starting position of the positive electrode in the second ring of the negative electrode in the electrode assembly, and not coating the positive electrode active material at the first bend, combined with the protection of the coating, the problem of insufficient utilization of the negative electrode active material is solved, and the energy density and reliability of the battery cell are improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CONTEMPORARY AMPEREX TECHNOLOGY CO LTD
- Filing Date
- 2026-04-08
- Publication Date
- 2026-07-17
AI Technical Summary
In the prior art, there is a situation where the negative electrode sheet is directly opposite the negative electrode sheet inside the winding structure of the electrode assembly, which makes it impossible to effectively utilize the inner negative electrode active material and makes it difficult to improve the energy density of the electrode assembly.
By placing the starting position of the positive electrode sheet in the second ring of the negative electrode sheet and leaving the first bend of the positive electrode sheet uncoated with positive active material, combined with the coating effect of the coating component, the first ring of the negative electrode sheet can effectively exert its capacity and reduce the risk of lithium plating.
It effectively improves the capacity density of electrode components and battery cells, reduces the risk of lithium plating in electrode components, and improves the service life and reliability of battery cells.
Smart Images
Figure CN224519921U_ABST
Abstract
Claims
1. A battery cell, characterized by, Includes a housing and an electrode assembly disposed within the housing, the electrode assembly comprising: A positive electrode sheet includes a positive current collector and a positive active material coated on the positive current collector; A negative electrode sheet includes a negative electrode current collector and a negative electrode active material coated on the negative electrode current collector; An isolator is disposed between the positive electrode and the negative electrode. The positive electrode, the isolator, and the negative electrode are stacked and wound together to form a flat region and a bent region connecting the two ends of the flat region in the electrode assembly. Wherein, the straight regions correspond to multiple positive straight portions of the positive electrode and multiple negative straight portions of the negative electrode, and the bending regions correspond to multiple positive bending portions of the positive electrode and multiple negative bending portions of the negative electrode. The positive electrode is located at the starting position of the second ring of the negative electrode, the negative electrode is located outside the positive electrode, and the first positive bend of the positive electrode is not coated with the positive active material.
2. The battery cell of claim 1, wherein, At least a portion of the first straight portion of the positive electrode sheet connected to the first positively bent portion of the positive electrode sheet is not coated with the positive electrode active material.
3. The battery cell of claim 1, wherein, The battery cell also includes: A covering is attached to the outer ring of the electrode assembly. The winding direction of the covering is consistent with that of the positive electrode, the separator, and the negative electrode. The overlap distance between the end position and the beginning position of the covering along the winding direction of the covering is a preset length.
4. The battery cell of claim 3, wherein, The termination positions of the positive electrode, the negative electrode, and the separator are all located within the same bending region; and / or, The covering material covers the electrode assembly at least one ring; and / or, The difference between the width of the covering and the width of the negative electrode sheet is greater than or equal to 1 mm; and / or, The thickness of the covering is 5~100μm; and / or, The preset length is greater than or equal to 1 mm; and / or, The covering is adhesive paper.
5. The battery cell of claim 3, wherein, The starting position of the covering overlaps with the ending position of the negative electrode sheet.
6. The battery cell of claim 5, wherein, The end position of the negative electrode extends beyond the end position of the positive electrode, and the starting position of the covering is aligned with the end position of the positive electrode along the winding direction.
7. The battery cell of any one of claims 1 to 6, wherein, The separator includes a first separator and a second separator, which are respectively stacked on both sides of the positive electrode sheet; The negative electrode is located outside the positive electrode, and the first and second separators are both located inside the negative electrode. The end position of the negative electrode extends beyond the end position of the positive electrode, and the end position of the separator is aligned with the end position of the negative electrode along the winding direction.
8. The battery cell of claim 7, wherein, The starting position of the negative electrode sheet is located in the straight area and avoids the bending area; the starting position of the separator is flush with the starting position of the negative electrode sheet.
9. The battery cell of claim 8, wherein, The starting position of the negative electrode sheet is oriented in the same direction as or opposite to the winding direction of the negative electrode sheet.
10. A battery device characterized by comprising: Includes the battery cell as described in any one of claims 1 to 9.
11. An electrical device, characterized by Includes the battery device of claim 10, for storing or providing electrical energy.