A novel high voltage SeBi positive material with stable cycling performance for liquid metal battery

Liquid metal batteries (LMBs) have broad application prospects in the field of large-scale energy storage due to its long cycle life and high rate-capability. However, the lower discharge voltage of present LMB systems limits its practical application. Selenium (Se) is a promising high-voltage positive electrode material for LMBs, while the poor conductivity and high solubility in molten salt electrolyte of pure Se material deteriorate its electrochemical properties and so severely impede the practical application. Herein, we propose a novel Se Bi alloying strategy to effectively enhance the conductivity of Se-based positive electrode and significantly inhibit the dissolution of Se in electrolyte. As a synergistic result, the designed Se 30 Bi 70 positive electrode delivers two high discharge voltage plateaus at ca. 1.65 and 1.20 V, which are much higher than those of conventional Bi-based and Sb-based positive electrodes, and exhibits an improved cycling performance capable of sustaining 100 cycles at a high current density of 300 mA cm −2 , outperforming the pure Se electrode.