Preparation and electrochemical property of Li₄Mn_5−xTi_xO₁₂ cathode materials for lithium ion battery by spray pyrolysis

Abstract

Li₄Mn_5−xTi_xO₁₂ (x = 0–0.5) powders were successfully prepared by ultrasonic spray pyrolysis. As-prepared Li₄Mn_5−xTi_xO₁₂ powders were calcined from 500 to 700°C. The chemical and physical properties of as-prepared Li₄Mn_5−xTi_xO₁₂ powders and the calcined powders were characterized by XRD, TG-DTA, and SEM. The crystal phases of as-prepared Li₄Mn_5−xTi_xO₁₂ powders crystallized to the spinel structure (Fd-3m) by the calcination at 500°C. As-prepared Li₄Mn_5−xTi_xO₁₂ powders and the calcined powders obtained by spray pyrolysis exhibited spherical morphology with approximately 2 µm. The electrochemical measurement showed that the discharge capacity of the Li₄Mn_5−xTi_xO₁₂ (x = 0) cathodes was 111 mAh/g at the rate of 0.2 C. The discharge capacity of the Li₄Mn_5−xTi_xO₁₂ cathodes increased with the concentration of Ti ion increased. The discharge capacity of the Li₄Mn_5−xTi_xO₁₂ (x = 5) cathodes increased to 171 mAh/g (0.2 C) with increasing up to x = 5. The retention rates of the Li₄Mn_5−xTi_xO₁₂ (x = 0, 2, 3, 5) cathodes discharge capacities were approximately 84, 66, 61, and 98% after 100 cycles at the rate of 1 C, respectively.