Regulation Roles of <i>p</i> ‐Block Elements in Lithium Layered Oxide Cathodes: Recent Progress and Perspectives

Abstract

ABSTRACT Layered oxides derived from Li x TM y O 2 (TM: Ni, Co, Mn and etc.), based on the de/intercalation mechanism, have long served as the backbone of lithium‐ion batteries (LIBs) for portable electronics, electric vehicles, and energy storage. However, the unstable structural evolution, sluggish diffusion kinetics, and detrimental interface parasitic reaction deteriorate their electrochemical performance. Due to p ‐block elements with unique electronic structures, the substitution in Li x TM y O 2 with p ‐block elements has become one of the mainstream practices. Therefore, clarifying the relationship among substitution, structure and performance is critical for rational design of high‐performance LIBs. However, a systematic review focusing on regulation roles of p ‐block elements in Li x TM y O 2 cathodes is lacking. Seeking to systematically understand the interaction between p ‐block elements with the matrix of Li x TM y O 2 cathodes, herein, we firstly outline the structure and mechanisms of Li x TM y O 2 cathodes, then highlight the internal structural degradation and external interface instability. And the performance enhancement mechanisms are emphasized in detail. Secondly, according to the order of the main group, a comprehensive review on the progress of p ‐block element substitution in Li x TM y O 2 are provided. Finally, the challenges and future perspectives are figured out, which can shed light on the design guideline of Li x TM y O 2 cathodes in the future.