A method for preparing a polyimide-coated separator with a gradient temperature control

By using a gradient temperature control preparation method, the problems of insufficient coating adhesion and uneven pore structure in polyimide coated separators were solved, achieving high thermal stability and electrolyte wettability, making it suitable for large-scale production.

CN122246420APending Publication Date: 2026-06-19CHONGQING HOUSHENG NEW MATERIAL TECHNOLOGY CO LTD
View PDF 0 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
CHONGQING HOUSHENG NEW MATERIAL TECHNOLOGY CO LTD
Filing Date
2026-03-23
Publication Date
2026-06-19

AI Technical Summary

Technical Problem

In the existing preparation process of polyimide coated diaphragms, the corona treatment parameters are not precise, which leads to unstable surface energy of the base film, insufficient adhesion between the coating and the base film, uneven pore structure, poor thermal stability and electrolyte wettability, and a narrow process window, making it difficult to achieve large-scale production.

Method used

The preparation method employs a gradient temperature control approach, which includes precise control of corona treatment parameters and a three-stage gradient temperature curing process. The ceramic particles are mixed with a polyamic acid precursor solution, coated onto the surface of a corona-treated polyolefin-based film, and then cured by gradient temperature control, followed by water washing and drying.

Benefits of technology

It significantly improved the adhesion between the coating and the base film, enhanced the uniformity of the pore structure, improved thermal stability and electrolyte wettability, broadened the process window, and enabled high-quality industrial production.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure SMS_1
    Figure SMS_1
Patent Text Reader

Abstract

This invention discloses a method for preparing a polyimide-coated separator with gradient temperature control, belonging to the field of lithium battery separator technology. The method includes mixing ceramic particles with NMP and dispersing them, then preparing a coating solution with a polyamic acid precursor solution; coating the coating solution onto the surface of a polyolefin-based membrane treated with a specific corona discharge, pre-drying, and then performing a three-stage gradient temperature curing process; finally, washing and drying to obtain the product. This invention significantly improves the adhesion between the coating and the base membrane, enhances the uniformity of the pore structure, improves thermal stability and electrolyte wettability, and broadens the process window by precisely controlling the corona treatment parameters and the gradient temperature curing process, making it suitable for large-scale industrial production.
Need to check novelty before this filing date? Find Prior Art