LiOH-mediated crystallization regulating strategy enhancing electrochemical performance and structural stability of SiO anodes for lithium-ion batteries  

作　　者：Zhengqiu He Zewen Xu Yu Long Jiexin Zhu Hao Yang Kuo Chen Qiang Zhou Ning Cao Xiaobo Wang Juan Wang Xiaojie Tan Litao Wang Luhai Wang Shengbao He Mengdi Zhang Han Hu Mingbo Wu 

机构地区：[1]State Key Laboratory of Heavy Oil Processing,College of Chemistry and Chemical Engineering,China University of Petroleum(East China),Qingdao 266580,China [2]Department of Chemistry,National University of Singapore,3 Science Drive 3,Singapore 117543,Singapore [3]School of Chemical Sciences,University of Auckland,Auckland 1010,New Zealand [4]Petrochemical Research Institute,Petro China Company Ltd.,Beijing 102206,China

出　　处：《Nano Research》2024年第9期8174-8183,共10页纳米研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.22138013);the Taishan Scholar Project(No.ts201712020).

摘　　要：Silicon monoxide(SiO)is widely recognized as a promising anode material for next-generation lithium-ion batteries.Owing to its metastable amorphous structure,SiO exhibits a highly complex degree of crystallization at the microscopic level,which significantly influences its electrochemical behavior.As a consequence,accurately regulating the crystallization of SiO,and further establishing the relationship between crystallinity and electrochemical performance are very critical for SiO anodes.In this article,carbon-coated SiO materials with different crystallinity degrees were synthesized using lithium hydroxide monohydrate(LiOH·H_(2)O)as a structural modifier to reveal this rule.Additionally,moderate amount of LiOH·H_(2)O addition results in the forming of an oxygen-rich shell,which effectively inhibits the inward migration of oxygen atoms on the SiO surface and suppresses volume expansion.However,the crystallinity of SiO will gradually enhance and the crystalline phase appears with increasing the amount of LiOH·H_(2)O,which will generate a deteriorative Li+diffusion kinetic.After balancing the above two contradictions,a mass fraction of 1%LiOH·H_(2)O for the additive yielded SiO@C-1,characterized by optimal crystallinity.SiO@C-1 demonstrates exceptional long-cycle stability with 74.8%capacity retention after 500 cycles at 1 A·g^(-1).Furthermore,it achieves a capacity retention of 52.2%even at a high density of 5 A·g^(-1).This study first reveals the relationship between SiO crystallinity and electrochemical performance,which efficiently guides the design of high-performance SiO anodes.

关 键 词：lithium-ion batteries SiO anodes crystallinity regulation high rate long life 

分 类 号：TM912[电气工程—电力电子与电力传动]