A Nb-doped metal hydride electrode with overcharge resistance and wide temperature performance for aqueous rechargeable batteries

Abstract

Metal hydride electrodes have been widely used for aqueous rechargeable batteries with good wide temperature performance compared to lithium-ion batteries. For the first time, the design and application of Nb-doped metal hydride electrode with excellent overcharge resistance in this study for La0.46Ce0.42-xPr0.03Nd0.08Zr0.02NbxNi4.41Mn0.36Al0.28 (x = 0, 0.05 or 0.1). The ratio of capacity retention after the 100th cycle for charging 420 and 360 mAh g−1 increases from 86.99% (x = 0) to 99.93% (x = 0.1) at 25 °C, and from 83.95% (x = 0) to 99.28% for (x = 0.1) at 50 °C. Furthermore, the capacity of simulated wide temperature and overcharge experiment at -20 °C increases from 86.3 mAh g−1 (x = 0) to 217.8 mAh g−1 (x = 0.1) after the 100th cycle at 50 °C, due to the increase of overcharge resistance. This material makes it a promising candidate as electrode material for wide temperature applications.