Nanofiber-reinforced polymer electrolytes toward room temperature solid-state lithium batteries

Safe and efficient utilization of electrochemical energy is of prime importance for e-mobility and sustainable development of the current society. Solid state batteries (SSBs) have emerged as one of the most promising solutions to address aforementioned challenges due to the replacement of conventional liquid electrolytes with inherently safer solid electrolytes. Polymer electrolyte (PE)-based SSBs have better processability and flexibility than inorganic electrolyte-based ones; however, the room temperature (RT) operation of the PE-based SSBs remains as one of the most critical issues. Herein, a nanofiber-reinforced polymer electrolyte (NRPE) comprising of poly(vinylidene fluoride) fibers along with a high molecular weight though flowable polymer matrix is proposed as an innovative electrolyte for SSBs. These NRPEs are self-standing, highly conductive, and stable against Li metal (Li°) electrode, endowing the Li° || LiFePO₄ cells with good performances at operational temperatures down to RT. The outstanding physicochemical and electrochemical properties of NRPEs make them as appealing candidates for attaining high-performance SSBs.