Separator and preparation method therefor
By using a three-layer separator structure and modified polymer microsphere coating technology, the problem of lithium battery temperatures exceeding the human body's tolerance limit during short circuits has been solved. This effectively reduces the risk of short-circuit temperature rise and thermal runaway without increasing battery volume and energy density, thereby improving battery safety and electrochemical performance.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- EVE ENERGY CO LTD
- Filing Date
- 2025-06-04
- Publication Date
- 2026-06-25
AI Technical Summary
Existing lithium batteries have surface temperatures that exceed the limits tolerable by the human body when short-circuited. External fuses or positive temperature coefficient materials increase battery volume and reduce energy density, and cannot effectively prevent medical accidents caused by short circuits.
A three-layer membrane structure is adopted, in which the first isolation layer is a ceramic material, the second isolation layer is a polymer material, and the third isolation layer is a modified polymer composite material. It is formed by coating a mixture of modified polymer microspheres, binders and thickeners to ensure that the membrane maintains structural integrity and stability in high-temperature environments, prevents positive and negative electrodes from contacting each other, and utilizes the pores of the polymer material to promote gas flow and heat dissipation.
Without increasing battery size, it effectively reduces short-circuit temperature rise, prevents short circuits and thermal runaway, improves battery safety and electrochemical performance, and ensures that the battery temperature does not exceed 50°C during a short circuit.
Smart Images
Figure CN2025099176_25062026_PF_FP_ABST