摘要
Abstract
This study investigated the ternary copolymer poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene)(P(VDF-TrFE-CFE))as a matrix material for advanced lithium-ion battery separators.Novel separators were fabricated using non-solvent-induced phase separa-tion(NIPS),thermally induced phase separation(TIPS),salt leaching(SL),and electrospinning(ES).A systematic investigation was carried out to elucidate the influence of these processing routes on the separator microstructure,pore architecture,electrochemical properties,and battery cycling performance.The results showed that the preparation method was a key factor governing the membrane microstructure and mechanical behavior.In particular,salt leaching and TIPS enabled effective tuning of separator porosity within the range of 23%~66%.All P(VDF-TrFE-CFE)separators exhibited relatively high ionic conductivity:the ES separators achieved a conductivity of up to 1.8 mS/cm,while the TIPS-derived separators showed a value of approximately 0.20 mS/cm.The lithium-ion transference numbers of all samples exceed 0.20,with maximum values of 0.55 obtained for the salt-leached and TIPS separators,indicating favorable ion-transport selectivity.Rate-capability tests revealed that batteries assembled with these separators deliver stable discharge capacities and excellent reversibility.Notably,the separators prepared by SL maintained a discharge capacity of around 41.9 mAh/g after 10 cycles at a 2 C rate.关键词
PVDF三元共聚物/P(VDF-TrFE-CFE)/锂离子电池隔膜Key words
PVDF ternary copolymer/P(VDF-TrFE-CFE)/lithium-ion battery separators分类
轻工纺织