锂离子电池凝胶聚合物隔膜的研究进展

Research Progresses on Gel Polymer Separators for Lithium-Ion Batteries

作为锂离子电池重要组分,隔膜由多孔聚烯烃高分子材料组成;电解质体系由有机碳酸酯和六氟磷酸锂混合组成,虽具有高离子电导率,但因液态碳酸酯的易燃特性给锂离子电池带来了安全隐患。利用能够将液态电解质体系凝胶化的聚合物制备得到的凝胶聚合物隔膜,结合了液态电解质体系高电导率和固态电解质高安全性的优点。凝胶聚合物隔膜的研究从简单微孔凝胶聚合物隔膜开始,经历了引入少量纳米无机颗粒的掺杂凝胶聚合物隔膜,到引入大量纳米颗粒的凝胶陶瓷隔膜的发展历程。本文详细介绍这三种类型凝胶聚合物隔膜的物理化学特性,最后展望凝胶聚合物隔膜的发展趋势。

An important component in lithium-ion batteries, the separator consists of porous polyolefin polymeric materials; the corresponding electrolyte is a liquid one composed of organic carbonate solvents and lithium hexafluorophosphate. Although the liquid electrolyte shows high lithium ion conductivity, its flammability poses a risk to the lithium-ion battery. A gel polymer separator prepared from a polymer that can gel the liquid electrolyte combines the advantages of high conductivity of the liquid electrolyte system and the safety of the solid electrolyte. Examples include the simple microporous gel polymer separator, the gel polymer separator doped with a small amount of nano-inorganic particles, and the gel ceramic separator with a large amount of nanoparticles. In this review, the physical and chemical properties of these gel polymer separators and development trends of gel polymer separators are discussed in detail.