Yu-Chan Yen

Enhanced High-Rate Cycling Stability of LiMn2O4 Cathode by ZrO2 Coating for Li-Ion Battery

The effect of a sol-gel derived amorphous zirconium oxide surface coating on the high charge-discharge (CD) rate performance of LiMn 2 O 4 was studied. When cycled between 4.5 and 2.9 V (vs. Li/Li + ) at room temperature, the coated spinel electrode, containing 5 wt %-ZrO 2 , shows tremendous enhancement in cycling stability at CD rates up to 10 C. Concurrently, the coated spinel electrode exhibits a lower cubic-tetragonal transition potential, a smaller charge-transfer impedance by 4-5-fold, and it profoundly reduces, by 66%, lattice contraction upon charge (delithiation). The enhancement in the high-rate cycling stability has been attributed to the combination of these favorable effects.