Facile fabrication of cellulose/polyphenylene sulfide composite separator for lithium-ion batteries

摘要

As an indispensable component, separator is close related to electrochemical performance and safety of lithium-ion batteries (LIBs). However, the current widely applied polyolefin microporous separator impedes the development of high power LIBs due to poorer electrolyte wettability and inferior thermal stability. Herein, heat-resistant polyphenylene sulfide (PPS) fibers and cellulose fibers (CFs) are adopted to fabricate a novel composite separator (CFs/PPS) via a facile papermaking process. The as-prepared CFs/PPS separator exhibits higher porosity, improved electrolyte uptake and superior wettability. These boost its ionic conductivity and decrease interfacial resistance between CFs/PPS separator and electrode, which further endow battery with good rate capability. Moreover, in comparison to commercial polypropylene separator, CFs/PPS separator gives superior thermal stability, satisfactory mechanical strength, broader electrochemical window and more stable cycle performance. Accordingly, CFs/PPS composite separator is very promising for application in high power LIBs.