LiNi 0.5 Mn 1.5 O 4 porous micro-cubes synthesized by a facile oxalic acid co-precipitation method as cathode materials for lithium-ion batteries

Abstract

Porous LiNi 0.5 Mn 1.5 O 4 (LNMO) micro-cubes have been synthesized via oxalic acid co-precipitation and sintering process. The sintering temperature has significant influence on the morphology and electrochemical performance of LNMO samples. The LNMO porous micro-cubes prepared by sintering at 770 oC are composed of the primary nanoparticles, and show the outstanding electrochemical properties. The discharge capacity of 116 mAh g -1 can be obtained at 1 C-rate after 200 charge-discharge cycles. Even at 5 C, the porous micro-cubes exhibit a discharge capacity of 90.2 mAh g -1 , corresponding to a capacity retention of 88.4% over 500 cycles. The excellent electrochemical performance may be ascribed to the porous cubic structure and the primary nanoparticles, which provide stable structure and short distance for lithium-ion diffusion.