A Superior Polymer Electrolyte with Rigid Cyclic Carbonate Backbone for Rechargeable Lithium Ion Batteries

Abstract

The fabricating process of well-known Bellcore poly(vinylidene fluoride-hexafluoropropylene) (PVdF-HFP)-based polymer electrolytes is very complicated, tedious, and expensive owing to containing a large amount of fluorine substituents. Herein, a novel kind of poly(vinylene carbonate) (PVCA)-based polymer electrolyte is developed via a facile in situ polymerization method, which possesses the merits of good interfacial compatibility with electrodes. In addition, this polymer electrolyte presents a high ionic conductivity of 5.59 × 10^-4 S cm^-1 and a wide electrochemical stability window exceeding 4.8 V vs Li⁺/Li at ambient temperature. In addition, the rigid cyclic carbonate backbone of poly(vinylene carbonate) endows polymer electrolyte a superior mechanical property. The LiFe_0.2Mn_0.8PO₄/graphite lithium ion batteries using this polymer electrolyte deliver good rate capability and excellent cyclability at room temperature. The superior performance demonstrates that the PVCA-based electrolyte via in situ polymerization is a potential alternative polymer electrolyte for high-performance rechargeable lithium ion batteries.