A gas-solid hydride ion battery

Progresses have been made in materials development for hydride ion (H−) conduction and H−-mediated electrochemical devices such as all-solid-state hydride ion batteries and cells. Gas-solid hydride ion battery (g-HIB), using H2 and light-weight metals as active materials of cathode and anode, respectively, offers potential for high capacity and energy density but has yet to be developed. Here, a typical metal-hydrogen system, Mg-H2, is employed to build such a g-HIB using the newly developed 3CeH3@BaH2 as electrolyte and LaNi5 as electrocatalyst. Experimental results validate that hydrogenation and dehydrogenation of the anode lead to electric energy output and input, respectively, over the Mg|3CeH3@BaH2|H2 developed. This g-HIB exhibits an initial capacity of 1526 mAh/g and maintains a capacity retention of over 70% after 60 cycles. It operates effectively across a wide temperature range of –20 to 90 ℃. Upon stacking, the battery generates an output voltage of 2.4 V and can power an LED bulb.