锂离子电池隔膜改性研究进展

Research Progress on Modification of Polyolefin-based Separators for Lithium-ion Batteries

锂离子电池作为便携式电子产品、新能源汽车、蓄电设备等产品电源备受关注。锂离子电池由正极、负极、隔膜和电解液四部分组成。隔膜虽然不直接参与锂离子电池中的电化学反应,但是隔膜作为锂离子电池的重要组成部分,其性质在很大程度上影响锂离子电池的性能。目前聚烯烃仍是使用最为广泛和商业化最为成功的锂离子电池隔膜材料,但因其不良的电解液浸润性和热稳定性,降低了锂离子电池的电性能和安全性,因此改性成为改善聚烯烃隔膜材料性能和推广应用的重要途径。本文从聚烯烃材料多层膜结构改性、表面涂覆改性和层层自组装改性三方面总结了近五年聚烯烃隔膜改性研究的最新进展。最后,提出增强聚烯烃隔膜的热稳定性和电化学性能仍是未来研究重点,并对新型隔膜材料进行展望。

Lithium-ion batteries have attracted extensive attention as a power source for portable electronic products,new energy vehicles,power storage equipment and other products.Lithium-ion batteries are composed of four parts:the anode(negative electrode),cathode(positive electrode),separator and electrolyte.Although the separator does not directly participate in the electrochemical reaction in lithium-ion batteries,as an important part of lithium-ion batteries,its properties greatly affect the performance of lithium-ion batteries.At present,polyolefin is still the most widely used and commercially successful separator material for lithium-ion battery,while because of its poor electrolyte wettability and thermal stability,the electrical properties and safety of lithium-ion batteries are reduced,so modification has become an important way to improve the performance and promotion of polyolefin separator materials.This paper summarizes the latest research progress on modification of polyolefin-based separators in the past five years through constructing of multilayer film method,surface coating technology and layer-by-layer self-assembly deposition technique.Finally,it is proposed that the thermal stability and electrochemical performance of polyolefin separators are still the key points of future research,and new separator materials are prospected.