Enhanced cyclic stability at elevated temperature of spinel LiNi0.5Mn1.5O4 by Li4Ti5O12 coating as cathode material for high voltage lithium ion batteries

Abstract The cyclic stability of LiNi 0.5 Mn 1.5 O 4 at elevated temperature is a crucial factor for commercial Li-ion batteries. To improve the capacity retention of the spinel cathode material, surface modification has been widely recognized as one of the most effective approaches. In this work, a continuous and uniform layer assembled with nanoscale Li 4 Ti 5 O 12 particles was coated on LiNi 0.5 Mn 1.5 O 4 via hydrothermal method with moderate temperature. With a coating quantity of 0.5 wt%, the as-prepared LiNi 0.5 Mn 1.5 O 4 @ Li 4 Ti 5 O 12 delivers an initial special discharge capacity of 141.2 mAh g −1 at 0.2 C and retention of 93.66% after 500 cycles at 1 C at room temperature, and it exhibits capacity retention of 97.03% after 140 cycles at 1 C at 55 °C. In addition to the protective effect against electrolyte, from observation on the surface feature during long term lithium insertion/extraction process, the Li 4 Ti 5 O 12 coating layer suppresses the continuous growth of a dense and cathode electrolyte interfaces from the electrolyte decomposition.