Spinel LiMn2O4 and LiCr x Mn2−x O4 (x=0.00−0.20) have been synthesized by a soft chemistry method using adipic acid as the chelating agent. This technique offers better homogeneity, preferred surface morphology, reduced heat-treatment conditions, sub-micron sized particles, and better crystallinity. The synthesized spinel materials are characterized by X-ray diffraction, scanning electron microscopy, cyclic voltammetry, and charge–discharge testing. It is found that chromium substitution alleviates capacity fading in the 4-V region and improves the structural stability of LiMn2O4 spinel upon repeated cycling.