Optimize two-phase distribution of lithium-rich materials to stabilize structure and suppress voltage attenuation

作     者：Yang Yu Jianling Li Guimei Han Zhe Yang Jianjian Zhong Feiyu Kang Yang Yu;Jianling Li;Guimei Han;Zhe Yang;Jianjian Zhong;Feiyu Kang

作者机构：State Key Laboratory of Advanced MetallurgySchool of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China Chinese Research Academy of Environmental SciencesBeijing 100012China School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China 

出 版 物：《International Journal of Minerals,Metallurgy and Materials》 (矿物冶金与材料学报（英文版）)

年 卷 期：2022年第29卷第12期

页      面：2201-2211页

核心收录：

学科分类：081702[工学-化学工艺] 08[工学] 0817[工学-化学工程与技术] 

基　　金：financially supported by the National Natural Science Foundation of China (Nos. 51972023 and 51572024) 

主　　题：lithium-rich phase tuning engineering stepwise co-precipitation voltage attenuation 1.Introduction 

摘      要：Lithium-rich materials possess the ultra-high specific capacity,but the redox of oxygen is not completely reversible,resulting in voltage attenuation and structural instability.A stepwise co-precipitation method is used for the first time in this paper to achieve the control of the two-phase distribution through controlling the distribution of transition metal elements and realize the modification of particle surface structure without the aid of heterologous *** results of characterization tests show that the content of LiMO_(2) phase inside the particles and the content of Li_(2)MnO_(3) phase on the surface of the particles are successfully increased,and the surface induced formation of Li_(4)Mn_(5)O_(12) spinel phase or some disorderly *** electrochemical performance of the modified sample is as follows:LR(pristine)shows specific discharge capacity of 72.7 mA·h·g^(−1)after 500 cycles at 1 C,while GR(modified sample)shows specific discharge capacity of 137.5 mA·h·g^(−1) at 1 C,and the discharge mid-voltage of GR still remains above 3 V when cycling to 220 cycles at 1 C(mid-voltage of LR remains above 3 V when cycling to 160 cycles at 1 C).Therefore,deliberately regulating the local state of the two phases is a successful way to reinforced the material structure and inhibition the voltage attenuation.