Revealing proton-coupled exchange mechanism in aqueous ion-exchange synthesis of nickel-rich layered cathodes for lithium-ion batteries  

作　　者：Yu-Hong Luo Qing-Lin Pan Han-Xin Wei Ying-De Huang Pei-Yao Li Lin-Bo Tang Zhen-Yu Wang Cheng Yan Jing Mao Ke-Hua Dai Qing Wu Xia-Hui Zhang Jun-Chao Zheng 

机构地区：[1]School of Materials Science and Engineering,Central South University,Changsha 410083,China [2]School of Metallurgy and Environment,Central South University,Changsha 410083,China [3]Engineering Research Center of the Ministry of Education for Advanced Battery Materials,Central South University,Changsha 410083,China [4]School of Mechanical,Medical and Process Engineering,Queensland University of Technology,Brisbane 4001,Australia [5]School of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450001,China [6]College of Chemistry,Tianjin Normal University,Tianjin 300387,China [7]School of Information and Network Center Central South University,Changsha 410083,China

出　　处：《eScience》2024年第4期103-109,共7页电化学与能源科学（英文）

基　　金：This work was supported by the National Natural Science Foundation of China(Grant No.51974368);This work was supported in part by the High Performance Computing Center of Central South University;This work was supported by the Beamlines 1W1B-XAFS at BSRF.

摘　　要：Ion exchange is a promising synthetic method for alleviating severe cation mixing in traditional layered oxide materials for lithium-ion batteries,leading to enhanced structural stability.However,the underlying mechanisms of ion exchange are still not fully understood.Such a fundamental study of the ion-exchange mechanism is needed for achieving the controllable synthesis of layered oxides with a stable structure.Herein,we thoroughly unearth the underlying mechanism that triggers the ion exchange of Ni-rich materials in aqueous solutions by examining time-resolved structural evolution combined with theoretical calculations.Our results reveal that the reaction pathway of ion exchange can be divided into two steps:protonation and lithiation.The proton is the key to achieving charge balance in the ion exchange process,as revealed by X-ray adsorption spectroscopy and inductive coupled plasma analysis.In addition,the intermediate product shows high lattice distortion during ion exchange,but it ends up with a most stable product with high lattice energy.Such apparent discrepancies in lattice energy between materials before and after ion exchange emphasize the importance of synthetic design in structural stability.This work provides new insights into the ion-exchange synthesis of Ni-rich oxide materials,which advances the development of cathode materials for high-performance lithium-ion batteries.

关 键 词：Ion exchange Reaction mechanisms Proton-coupledNi-rich oxides PROTONATION LITHIATION Lithium-ion batteries 

分 类 号：TM912[电气工程—电力电子与电力传动]