Improvement in the safety and performance of polyethylene/montmorillonite composite separator for lithium-ion batteries by silane surface treatment and electron irradiation

Abstract

The membrane plays a crucial role in both the safety and performance aspects of a battery. In this study, a polyethylene/montmorillonite composite membrane for lithium-ion batteries was manufactured using silane surface treatment and electron beam irradiation to enhance stability and performance. Silane surface treatment modified the hydrophilic montmorillonite to be hydrophobic, ensuring high dispersion within the polyethylene matrix. Additionally, electron beam irradiation induced cross-linking reactions between polyethylene chains, as well as between polyethylene chains and the functional groups of the silane coupling agent, strengthening both mechanical and thermal properties of the membrane. Furthermore, electron beam irradiation in ambient air induced oxidation reactions, promoting oxygen cross-linking in the membrane and enhancing electrolyte affinity, thereby improving electrochemical performance.