LiMg 0.1 Co 0.9 BO 3 as a positive electrode material for Li-ion batteries.

LiCoBO 3 could be a promising cathode material given the electronic and ionic conductivity problems are addressed. Here, Mg substitution in LiCoBO 3 is employed to stabilise the structure and improve the electrochemical performance. LiMg 0.1 Co 0.9 BO 3 is synthesised for the first time via sol-gel method and Mg substitution in the structure is verified by X-ray powder diffraction and energy dispersive X-ray analyses. The electrochemical properties are investigated by galvanostatic cycling and cyclic voltammetry tests. The composite electrode with conductive carbon (reduced graphite oxide and carbon black) delivers a first discharge capacity of 32 mA h g -1 within a 4.7-1.7 voltage window at a rate of 10 mA g -1 . The cycling is relatively stable compared to the unsubstituted LiCoBO 3 . Mg substitution may enhance the electrochemical performance of borate-based electrode materials when combined with suitable electrode design techniques.