Manipulating Interfacial Stability via Preferential Absorption for Highly Stable and Safe 4.6 V LiCoO_(2) Cathode  

作　　者：Long Chen Xin He Yiqing Chen Youmin Hou Yujie Zhang Kangli Wang Xinping Ai Yuliang Cao Zhongxue Chen 

机构地区：[1]Key Laboratory of Hydraulic Machinery Transients,Ministry of Education,School of Power and Mechanical Engineering,Wuhan University,Wuhan 430072,People’s Republic of China [2]State Key Laboratory of Advanced Electromagnetic Technology,School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074,People’s Republic of China [3]Hubei Key Laboratory of Electrochemical Power Sources,College of Chemistry and Molecular Sciences,Wuhan University,Wuhan 430072,People’s Republic of China

出　　处：《Nano-Micro Letters》2025年第8期95-110,共16页纳微快报(英文版)

基　　金：financially supported by National Key Research and Development Program of China(2024YFE0213000);National Natural Science Foundation of China(No.U22A20438);Hubei Natural Science Foundation(2023BAB036,2024BAB103);the Key Research and Development Program of Ningxia Hui Autonomous Region(2024BEE02002).

摘　　要：Elevating the upper cutoff voltage to 4.6 V could effec-tively increase the reversible capacity ofLiCoO_(2)(LCO)cathode,whereas the irreversible structural transition,unstable electrode/electrolyte interface and potentially induced safety hazards severely hinder its industrial application.Building a robust cathode/electrolyte interface film by electrolyte engineer-ing is one of the efficient approaches to boost the performance of high-voltage LCO(HV-LCO);however,the elusive interfacial chemistry poses substantial challenges to the rational design of highly compatible electrolytes.Herein,we propose a novel electrolyte design strategy and screen proper solvents based on two factors:highest occupied molecular orbital energy level and LCO absorption energy.Tris(2,2,2-trifluoroethyl)phosphate is determined as the optimal solvent,whose low defluorination energy barrier significantly promotes the construction of LiF-rich cathode/electrolyte interface layer on the surface of LCO,thereby eventually suppresses the phase transition and enhancesLi+diffusion kinetics.The rationally designed electrolyte endows graphite||HV-LCO pouch cells with long cycle life(85.3%capacity retention after 700 cycles),wide-temperature adaptability(-60–80℃)and high safety(pass nail penetration).This work provides new insights into the electrolyte screening and rational design to constructing stable interface for high-energy lithium-ion batteries.

关 键 词：Electrolyte design LiF-rich interface Wide-temperature High-safe 4.6 V LCO 

分 类 号：TM912[电气工程—电力电子与电力传动]