The dissolution behaviors of manganese and chromium-ions of LiMn2−x Cr x O4 have been investigated at various temperatures. When the LiMn2−x Cr x O4 powders were soaked in the LiPF6-containing electrolyte, the dissolution of manganese-ions as well as chromium-ions took place. With an increase of chromium-ions in LiMn2−x Cr x O4, the amounts of dissolved manganese-ions significantly decreased at room and elevated temperatures. This indicates that doping chromium-ions in LiMn2O4 can suppress the dissolution reaction of manganese-ions at elevated temperatures, thereby leading to lowered degree of capacity deterioration. On the other hand, raising the immersion temperature significantly increased the amounts of dissolved manganese and chromium-ions. It was also demonstrated that operation temperatures play an important role in the dissolution in both undoped and chromium-ion doped LiMn2O4.