首页> 外文期刊>Advanced energy materials >Stepwise Dopant Selection Process for High-Nickel Layered Oxide Cathodes
【24h】

Stepwise Dopant Selection Process for High-Nickel Layered Oxide Cathodes

机译:Stepwise Dopant Selection Process for High-Nickel Layered Oxide Cathodes

获取原文
获取原文并翻译 | 示例
           

摘要

NCM-based lithium layered oxides (LiNi1-x-yCoxMnyO2) have become prevalent cathode materials in state-of-the-art lithium-ion batteries. Higher energy densities can be achieved in these materials by systematically increasing the nickel content; however, this approach commonly results in inferior cycle stability. The poor cycle retention of high-nickel NCM cathodes is generally attributed to chemo-mechanical degradation (e.g., intergranular microcracks), vulnerability to oxygen-gas evolution, and the accompanying rocksalt phase formation via cation mixing. Herein, the feasibility of doping strategies is examined to mitigate these issues and effective dopants for high-nickel NCM cathodes are theoretically identified through a stepwise pruning process based on density functional theory calculations. Specifically, a sequential three-step screening process is conducted for 38 potential dopants to scrutinize their effectiveness in mitigating chemo-mechanical lattice stress, oxygen evolution, and cation mixing at charged states. Using this process, promising dopant species are selected rationally and a silicon-doped LiNi0.92Co0.04Mn0.04O2 cathode is synthesized, which exhibits suppressed lattice expansion/contraction, fewer intergranular microcracks, and reduced rocksalt formation on the surface compared with its undoped counterpart, leading to superior electrochemical performance. Moreover, a comprehensive map of dopants regarding their potential applicability is presented, providing rational guidance for an effective doping strategy for high-nickel NCM cathodes.

著录项

获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号