Thermoelectrochemical Activation of CoO in Na Cells

Abstract

© 2018 The Electrochemical Society. CoO is normally electrochemically inactive in sodium half-cells at room temperature. Here, it was found that CoO has significant electrochemical activity when cycled at 60◦C (up to 550 mAh/g). In addition, CoO could be made electrochemically active at 30◦C after undergoing one sodiation half-cycle at 60◦C. Such in-situ thermoelectrochemical activation was found to be advantageous over ball milling. Combining ball milling with thermoelectrochemical activation, resulted in the highest reversible capacity achieved for CoO (300 mAh/g or 1800 Ah/L) and the best cycling retention.