A novel Sb-Zn electrode with ingenious discharge mechanism towards high-energy-density and kinetically accelerated liquid metal battery

Liquid metal battery (LMB) has recently captured intensive attention for large-scale energy storage, originating from its attractive cost-efficiency, robust cyclability, and ultralong service lifetime. Nevertheless, realizing high energy density remains a great challenge. Herein, a novel dual-active Sb-Zn electrode is elaborately designed. A unique lithiation mechanism is demonstrated for the first time in LMB field. A ternary intermetallic compound LiZnSb is preferentially formed with a high discharge plateau at ca. 1.1 V, which is followed by a conversion reaction to Li3Sb and Zn at around 0.8 V and then a consecutive dissolution reaction of lithium in molten Zn, significantly ameliorating the voltage and capacity properties. Meanwhile, part Zn melts regenerate and disperse among discharge product layer, constructing rapid electron/lithium percolating networks in-situ, which accel-erates the electrode reaction kinetics. As a result, the Li||Sb-Zn battery exhibits high average discharge voltage of 0.763 V at 100 mA cm-2 and superior rate performance (0.596 V at 1000 mA cm-2). Outstanding energy and power densities (290.6 Wh kg-1 and 239.66 W kg-1) are achieved, remarkably surpassing most reported LMBs and even comparable to Na-S battery. This work showcases an innovative electrochemistry system, opening a new avenue for high-performance LMBs.