Effect of the NO_3~-/CH_3COO~- ratio on structure and performance of ultrafine LiMn_2O_4 by solution combustion synthesis

摘要

Ultrathin LiMn_2O_4 was successfully prepared by calcinating at 700 °C following solution combustion synthesis. The effects of NO_3~-/CH_3COO~- ratio of starting materials on the structure and electrochemical performance are investigated. XRD results indicate that LiMn_2O_4 samples prepared with a NO_3~-/CH_3COO~-ratio of 3:2 (LMO3) has the smallest nanocrystallite of 36.1 nm. SEM results reflect that LMO3 has the smallest average primary particles of 210 nm. These features ensure LMO3 have the excellent electrochemical performance. It even can deliver a capacity of 95.5 mA h g~(-1) at charge-discharge rate of 10 C. The charge-discharge voltage profiles, dQ/dV versus voltage curves and EIS test all indicate LMO3 has the best electrochemical performance.