A Durable Gel Polymer Electrolyte with Excellent Cycling and Rate Performance for Enhanced Lithium Storage

Abstract

High-energy rechargeable Li-metal batteries require safer and more reliable electrolyte systems because of the dendrite growth caused by the organic liquid electrolytes. Polymer electrolytes with both high electrochemical and mechanical properties are expected, although they are challenging to prepare. Herein, a novel gel polymer electrolyte (GPE) based on poly(vinylidene fluoride) (PVDF) has been fabricated by introducing laponite nanoplates via a facile solution-casting method. The composite GPE shows a high ion conductivity and mechanical strength. When applied to LIBs with LiFePO4 as cathode, the battery exhibits a high capacity of 157 mA h g–1 at 0.2 C with an excellent initial Coulombic efficiency of 95%. After 1000 cycles, the capacity retention is as high as 97%. Remarkably, a superior capacity of 111 mA h g–1 is still maintained at a high rate of 10 C. This result provides a way to design a high-performance electrolyte and flexible devices.