m-LiCrxMn1-xO2 solid solution has been synthesized by a solid state reaction method. The samples obtained show a first charging voltage of similar to 4 V against a lithium electrode, but develops 4- and 3-V plateaus upon cycling, indicating transformation to spinel-like cation ordering within the oxide. Unlike previously reported lithium manganese spinels, the compound of this study shows excellent reversible capacity (> 160 mA h/g at C/5 rate) when cycled over both the 4- and 3-V plateaus. The discharge capacity fade rate of samples decreases with an increase in Cr substitution, and H2SO4 treatment could further improve the electrochemical performance of samples.