A low dimensional composite of hexagonal lithium manganese borate (LiMnBO3), a cathode material for Li-ion batteries

Abstract

The ultrasonic nebulized spray pyrolysis technique has been applied to synthesize amorphous nanospheres, which are further transformed into nano h-LiMnBO₃ with an average crystallite size of ∼14 nm. A composite electrode of nano h-LiMnBO₃ with reduced graphite oxide and amorphous carbon delivers a high first discharge capacity of 140 mA h g⁻¹ at C/15 rate within 4.5–2.0 V and retains a discharge capacity of 110 mA h g⁻¹ at the 25^th cycle. The dissolution of Mn into the electrolyte and the instability of the highly delithiated phases during cycling are suggested as the reasons, which limit the cycling stability of h-LiMnBO₃. An improved cycling stability at higher capacities is expected via the combination of the particle size reduction, conductive network formation and the metal site doping strategies.