电池包及用电设备
By using a positive temperature coefficient thermistor as a protection element in a lithium-ion battery pack, the impedance of which is positively correlated with temperature, the thermal runaway problem caused by overcharging is solved, thereby improving the safety and stability of the battery pack.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- EVE ENERGY CO LTD
- Filing Date
- 2025-04-23
- Publication Date
- 2026-07-17
AI Technical Summary
Overcharging lithium-ion batteries can lead to thermal runaway, causing safety accidents such as combustion or explosion.
A positive temperature coefficient thermistor is used as the protection unit and connected in series with the battery cell. Its impedance is positively correlated with temperature. Heat is conducted to the protection unit through the connection to increase the impedance, suppress the voltage and limit the charging current.
It effectively prevents thermal runaway of the battery pack during overcharging, improves safety and stability, and reduces the risk of thermal runaway.
Smart Images
Figure CN224520138U_ABST
Abstract
Claims
1. A battery pack, characterized by, include: At least two battery cells, each battery cell including electrode terminals; A connecting portion is disposed on one side of the battery cell, and the connecting portion is electrically connected to the electrode terminals of at least two of the battery cells; A protective part is disposed on the side of the connecting part away from the electrode terminal, and the protective part is connected in series with the battery cell through the connecting part; The impedance of the protection part is positively correlated with the temperature of the protection part.
2. The battery pack of claim 1, wherein, The coefficient of thermal expansion of the connecting part is greater than that of the protective part.
3. The battery pack of claim 2, wherein, The connecting part is fixed to the electrode terminal by welding.
4. The battery pack of claim 3, wherein, The connecting portion is provided with a first through hole, and the first through hole is provided corresponding to the electrode terminal; The protective part has a second through hole, which is provided corresponding to the first through hole, and the diameter of the second through hole is greater than or equal to the diameter of the first through hole.
5. The battery pack of claim 2, wherein, The protective part is projected onto the battery cell and is located within the projection of the connecting part onto the battery cell.
6. The battery pack of any one of claims 1-5, wherein, The protection element is a positive temperature coefficient thermistor with a transition temperature between 90°C and 130°C.
7. The battery pack of claim 6, wherein, The resistance of the protection unit is greater than or equal to 2.2 megohms and less than or equal to 5 megohms.
8. The battery pack of claim 6, wherein, The thickness of the protective part is greater than or equal to 0.3 mm and less than or equal to 0.5 mm.
9. The battery pack of any one of claims 1-5, wherein, The connecting portion includes a first connecting sub-port, a second connecting sub-port, and a connecting segment connecting the first connecting sub-port and the second connecting sub-port; In one of two adjacent battery cells, the first connecting part is electrically connected to the electrode terminal of one battery cell, and the second connecting part is electrically connected to the electrode terminal of the other battery cell. The protective part is disposed on the surface of at least one of the first connecting part and the second connecting part.
10. An electric device, characterized by Includes the battery pack as described in any one of claims 1 to 9.