Highly Stable Hybrid Electrolyte Lithium-Air Batteries Based on Weakly Acidic Lithium Bromide Catholyte

Abstract

Hybrid lithium-air battery (HLAB) have garnered significant attention from researchers due to their relatively low overpotential, stable cyclability, and reversibility. In this paper, we investigate an HLAB system that uses a catholyte of lithium bromide solution in a weak acid state to enhance the stability of Li1−xAlxGe2−x(PO4)3 (LAGP) and improve its cycle life. The electrochemical performance of the optimized LiBr electrolyte exhibited stability after 443 cycles (1772 h) in ambient air (RH = 15%). Additionally, an improvement of >20% in coulombic efficiency was observed at a discharge specific capacity of 10736 mAh·g−1 compared to HLABs using LiOH electrolyte. This study provides insights into the protection of LAGP membranes in HLAB and the inhibition of reaction product precipitation.