Development of metal hydride material efficient surface in conditions of galvanostatic charge/discharge cycling

• Sn-doped hydride electrode cycling increases its efficient surface area.
• Evans approach to electrode potential changes allows surface development evaluation.
• The hydride material porosity increases both during its charging and discharging.

A detailed analysis of potential changes on galvanostatic charge/discharge curves for LaNi4.5Co0.5Sn0.1 powder-composite electrode has been carried out with regard to material surface development as a result of hydrogenation. It has been shown that the efficient surface of the electrode increases mainly during its cathodic charging. The surface development caused by hydrogen desorption is evident for the first cycle only. Electrode cycling is prone to continuous surface development which is especially distinct for some first cycles.