Improving the electrochemical performance of LiNi0.8Co0.1Mn0.1O2 cathodes using a simple Ce4+-doping and CeO2-coating technique

• Published in: New journal of chemistry 2021-11, Vol.45 (46), p.21617-21623
• Main Authors: Feng, Yanhua, Zhang, Xiangxin, Lin, Changxin, Wang, Qichao, Zhang, Yining
• Format: Article
• Language: English
• Subjects: Attenuation; Cathodes; Cerium oxides; Diffusion coating; Doping; Electrochemical analysis; Flux density; Interface reactions; Lithium; Lithium-ion batteries; Rechargeable batteries; Structural stability
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/d1nj04997f

LiNixCoyMn1−x−yO2 (x ≥ 0.6, NCM) has attracted much attention due to its high specific capacity and energy density. However, capacity attenuation caused by Li+/Ni2+ mixing and structural instability inhibit its development and application. In order to solve these problems, we report a simple method to synthesize NCM cathodes via a one-step Ce4+-doping and CeO2-coating technique, which can reduce the degree of Li+/Ni2+ mixing and improve the structural stability. The Ce4+-doping not only effectively reduces the degree of Li+/Ni2+ mixing, but also enhances the (001) interplanar distance of NCM and improves Li+ diffusion. Furthermore, the CeO2-coating can reduce the direct contact between the NCM particles and electrolyte, which can reduce the harmful interface reaction, thus making the impedance increase more slowly. The Ce4+-doping and CeO2-coating of NCM particles led to a capacity retention of 96.3% at 1C (1C = 280 mA g−1) after 100 cycles. Therefore, the synthesis of NCM cathodes via a one-step Ce4+-doping and CeO2-coating technique is a superb way to improve the electrochemical properties of the NCM cathode in lithium-ion batteries.