Robust Self-Standing Single-Ion Polymer Electrolytes Enabling High-Safety Magnesium Batteries at Elevated Temperature

摘要

Rechargeable magnesium batteries (RMBs) have great potential in the field ofhigh-temperature specialized batteries owing to the superior thermostabilityand lower propensity for dendrite formation of Mg metal anodes. And thedevelopment of Mg~(2+)-conducting electrolytes that can operate stably underelevated temperature conditions (>100 ℃) is the key to high-temperatureRMBs. Here, a robust self-standing single-ion polymer electrolyte (SSPE)enabling high-safety RMBs working at elevated temperature is presented.This SSPE exhibits an expanded electrochemical stability window of 4.8 V (vsMg~(2+)/Mg), a remarkable Mg~(2+)-ion transference number of 0.79, and a highlyreversible Mg plating/stripping performance. This rationally designed SSPEenables home-made Mo_6S_8//Mg batteries with superior high-temperature(up to 150 ℃) performance and significantly improved safety characteristicsunder abuse conditions. This design concept for a robust SSPE provides apromising path to high-safety specialized RMBs operating at the elevatedtemperature, which also offers a new path for the development of functionalizedelectrolytes.