Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries  

作　　者：Xinyuan Wang Fan Zhang Xingyu Zhou Qian Wang Changyu Liu Yangyang Liu Hui Wang Xiaojie Liu 

机构地区：[1]Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education,College of Chemistry&Materials Science,Northwest University,Xi’an 710127,Shaanxi,China

出　　处：《Journal of Energy Chemistry》2025年第1期509-521,共13页能源化学(英文版)

基　　金：National Natural Science Foundation of China (52372224 and 52072299);Major Project of Shaanxi Coal Joint Fund of Shaanxi Provincial Science and Technology Department (2019JLZ-07)。

摘　　要：Na_(3)V_(2)(PO_(4))_(2)O_(2)F (VP) is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific capacity.Density functional theory (DFT) and finite element simulations show that incorporating SO_(4)^(2-)into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge cycles.Consequently,the average Na+diffusion coefficient of Na_(3)V_(2)(PO_(4))_(1.95)(SO_(4))_(0.05)O_(2)F(VPS-1) is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g^(-1)) and cycling stability (111.0 mAh g^(-1)capacity after 1000 cycles at 10 C current density) for VPS-1.VPS-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 min.The assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关 键 词：Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode 

分 类 号：TM912[电气工程—电力电子与电力传动] O646[理学—物理化学]