The origins of kinetics hysteresis and irreversibility of monoclinic Li_(3)V_(2)(PO_(4))_(3)  

作　　者：Hua Huo Zeyu Lin Guiming Zhong Shuaifeng Lou Jiajun Wang Yulin Ma Changsong Dai Yueping Xiong Geping Yin Yong Yang 

机构地区：[1]Key Laboratory of Materials for New Energy Conversion and Storage(Ministry of Industry and Information Technology),School of Chemistry and Chemical Engineering,Harbin Institute of Technology,Harbin 150001,Heilongjiang,China [2]State Key Laboratory for Physical Chemistry of Solid Surface and Department of Chemistry,College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,Fujian,China [3]Xiamen Institute of Rare Earth Materials,Haixi Institutes,Chinese Academy of Sciences,Xiamen 361021,Fujian,China

出　　处：《Journal of Energy Chemistry》2022年第4期593-603,共11页能源化学（英文版）

基　　金：supported by the National Natural Science Foundation of China(21673065,21403045,21473148);the Public Project of State Key Laboratory for Physical Chemistry of Solid Surface and Department of Chemistry,Xiamen University(201407)。

摘　　要：Monoclinic Li_(2)V_(2)(PO_(4))_(3);is a promising cathode material with complex charge–discharge behavior.Previous structural investigation of this compound mainly focuses on local environments;while the reaction kinetics and the driving force of irreversibility of this material remain unclear.To fully understand the above issues,both the equilibrium and the non-equilibrium reaction routes have been systematically investigated in this study.Multiple characterization techniques including X-ray diffraction,variable temperature(spinning rate)and ex/in situ ^(7)Li,^(31)P solid state NMR have been employed to provide comprehensive insights into kinetics,dynamics,framework structure evolution and charge ordering,which is essential to better design and application of lithium transition metal phosphate cathodes.Our results suggest that the kinetics process between the non-equilibrium and the quasi-equilibrium delithiation pathways from Li_(2)V_(2)(PO_(4))_(3);to V_(2)(PO_(4))_(3);is related with a slow relaxation from two-site to one-site delithiation.More importantly,it has been demonstrated that the irreversibility in this system is not solely affected by cation and/or charge ordering/disordering,but mainly driven by framework structure distortion.

关 键 词：NMR spectroscopy ELECTROCHEMISTRY Solid-state structures KINETICS 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ131.11[化学工程—无机化工]