Stabilizing Commercial LiMn₂O₄ Cathode by Constructing Protective Saccharin Coating

LiMn 2 O 4 (LMO) is a promising cathode material for Li-ion batteries due its low cost and eco-friendliness. However, the rapid capacity decay caused by side reactions and Mn-ion dissolution hinder the application of LMO. Herein, a hydrothermal route was adopted to modify commercial LMO with saccharin (SAC). At a mass ratio of 1:0.01 for LMO and SAC, the SAC-modified LMO reveals significantly improved rate performance (capacity retention increases by nearly 30% at 5C) and cycling stability. The improvement in performance is associated with the stabilized spinel structure of LMO during cycling, the protective SAC coating for avoiding direct interaction of LMO with electrolyte and suppressing Mn-ion dissolution, the N–Mn bonds for strengthening anchoring to LMO, and the −SO 2 – groups in SAC for favoring Li-ion migration. The modification of LMO with SAC is effective and scalable for industrial application.