Improving the Electrochemical Performance of Ni-Rich LiNi0.8Co0.1Mn0.1O2 Cathodes by Suitable Sintering Temperature

Abstract

Ni-rich layered LiNi_xCo_yMn_zO₂ (NCM, x ≥ 0.6) is one of the most competitive cathode materials due to its high energy density. However, its fast capacity fading, high voltage instability, serious parasitic reactions, phase transitions, and loss of active substances hinder further large-scale applications. In this work, we used the highest sintering temperature for LiNi_0.8Co_0.1Mn_0.1O₂ material (named NCM811). NCM811-800 °C which was sintered at 800 °C for 10 h significantly enhanced the materials’ structural stability due to the suppression of the cathode materials degradation during cycling. Correspondingly, NCM811-800 °C shows the best electrochemical performance among four samples, ∼81.3% (161.6 mAh/g) with a rate of 0.5C after 200 cycles, much higher than that of the worst sample NCM811-750 °C, only remaining 89.1 mAh/g (about 48.2% capacity retention). Meanwhile, the rate capacity of NCM811-800 °C also presents superior stability (97.6, 89.9, 81.1, and 43.6% under 0.1, 0.5, 1, 2, and 5C) with improving the structural stability of cathodes. Our work provides a practical method to improve the electrochemical properties of Ni-rich layered structure cathode by suitable sintering temperature.