Effect of annealing on the electrochemical properties of ramsdellite-type lithium titanium oxide

► We studied the properties of a ramsdellite-type lithium titanium oxide. ► In a half Li-cell, it showed a high discharge capacity of 250 mA h g−1. ► The capacity decay was observed after stored the powder in a dry atmosphere. ► Annealing well recovered the capacity loss after storage. ► XPS study suggested adsorbed carbon-based molecules might block the Li transport.