Li-rich compounds have received significant attention as electrode materials for lithium-ion batteries (LIBs) because of their large rechargeable capacities (qrecha). We have demonstrated a novel reaction scheme of one of the Li-rich compounds, Li[Li0.15Mn1.85]O4, where Mn4+ ions are reduced to lower valence states such as Mn3+ and Mn2+ ions during charging at voltages above 5.0 V.