Demonstration of Co3+/Co2+ Electrochemical Activity in LiCoBO3 Cathode at 4.0 V

Reversible electrochemical activity involving Co3+/Co2+ redox reaction has been observed in LiCoBO3 for the first time. Prepared by a two-step solid-state route and followed by cathode optimization, the LiCoBO3 product induces Li (de) insertion reaction at 4 V vs. Li. Although the capacity is limited to 30 mAh/g, it establishes LiCoBO3 as a possible high-voltage cathode material for Li-ion batteries. Structural and electrochemical analyzes show the net cathode performance is presumably limited by the Co-dissolution and amorphization at electrode-electrolyte interface. (c) 2013 The Electrochemical Society.