UV-Crosslinked Battery Separator Coating for High Heat Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium-ion battery separators face challenges in achieving high heat resistance and breakage temperature using conventional organic-solvent mixed coating processes, particularly due to poor adhesion and cross-linking of high heat-resistant resin binders during the coating process, leading to compromised performance.
Innovation Solution
A coating slurry comprising an ultra-high heat-resistant polymer resin binder, an auxiliary binder, a cross-linking agent, and an inorganic filler is used, which is coated on a substrate and subjected to ultraviolet light radiation to form an ultraviolet cross-linked separator, enhancing adhesion and heat resistance through a uniform macromolecular network structure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional organic-solvent mixed coating processes are used, then the manufacturing process is simple, but the adhesion and cross-linking of high heat-resistant resin binders are poor
Solution Approach 1:
The patent changes the fundamental parameter of the coating solvent from conventional organic solvents to water-based solvent system, which enables better adhesion and cross-linking of high heat-resistant resin binders while maintaining process simplicity. The water-based slurry allows for effective UV cross-linking and forms a uniform macromolecular network structure.
Solution Approach 2:
The patent uses a composite coating formulation comprising water-based solvent, high heat-resistant polymer resin binder (melting point above 200°C), auxiliary binder, cross-linking agent, and inorganic filler. This composite material system synergistically improves adhesion, cross-linking performance, and heat resistance while maintaining manufacturing simplicity.
2Temperature
If high heat-resistant resin binders are used, then the heat resistance is improved, but the cross-linking and adhesion during coating process deteriorate
Solution Approach 1:
The patent introduces auxiliary binders and cross-linking agents as intermediary substances that mediate between the high heat-resistant resin binder and the substrate. The auxiliary binder (1-20 wt%) provides adhesion promotion, while the cross-linking agent (0.001-6 wt%) enables network formation, allowing the high heat-resistant binder to maintain its thermal properties while achieving good adhesion and cross-linking.
Solution Approach 2:
The patent changes the chemical environment by using water-based solvent instead of organic solvent, which fundamentally alters how the high heat-resistant resin binder interacts with the substrate and cross-linking agents. This parameter change enables the binder to achieve both high heat resistance and good adhesion/cross-linking performance simultaneously.
3Temperature
If organic-solvent coating is used, then the coating process is simple, but the heat resistance and breakage temperature are insufficient
Solution Approach 1:
The patent changes the solvent base from organic to water-based, which enables the use of high heat-resistant polymer resin binders (melting point above 200°C) that can achieve breakage temperatures greater than 180°C. Despite this fundamental parameter change, the coating process remains simple through UV irradiation cross-linking, maintaining ease of manufacture.
4Reliability
If UV cross-linking is applied, then the adhesion and heat resistance are improved, but the process complexity increases
Solution Approach 1:
The patent replaces traditional thermal curing or chemical curing mechanisms with UV light-induced cross-linking. This substitution allows for rapid, controlled, and uniform cross-linking of the coating layer without requiring complex heating equipment or prolonged chemical reaction times, thus improving adhesion and heat resistance while adding minimal process complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution significantly improves the heat resistance and breakage temperature of the separator, ensuring safety and performance enhancements while maintaining cost-effectiveness and simplicity in the manufacturing process.
Implementation Method 1
the coating slurry is coated on at least one surface of the substrate and subjected to ultraviolet light radiation treatment with set energy and set wavelength to obtain an ultraviolet cross-linked separator
Data Source
AI summary
The present application provides a coating slurry, a separator, a preparation method, and a battery. Main components of the coating slurry include a solvent, an ultra-high heat-resistant polymer resin binder, an auxiliary binder, a cross-linking agent, and an inorganic filler. According to the present application, the heat resistance and breakage temperature of the separator are successfully improved at a low cost by using a simple formula, thereby greatly improving the safety of a battery.