Li_(3)VO_(4) is a promising electrode material for next-generation lithium-ion batteries(LIBs)due to its excellent specific capac-ity(592 mAh g^(−1)),suitable discharge voltage(0.5-1.0 V),and moderate volume change up...Li_(3)VO_(4) is a promising electrode material for next-generation lithium-ion batteries(LIBs)due to its excellent specific capac-ity(592 mAh g^(−1)),suitable discharge voltage(0.5-1.0 V),and moderate volume change upon charge/discharge,while it still suffers from low electronic conductivity that usually gives a poor rate capability,low initial coulombic efficiency,and large polarization,imposing a challenge on its practical applications.In this work,a partial surface phase transformation of Li_(3)VO_(4) was initiated via a freeze-drying method followed by a heat treatment in inert gas.Using this method,Li_(3)VO_(4) was integrated with a conductive layer LiVO_(2) and carbon matrix.The synergistic effect among Li_(3)VO_(4),LiVO_(2) layer,and carbon matrix was systematically studied by optimizing the treatment conditions.When treated at 600°C in Ar,Li_(3)VO_(4)-based composite delivered outstanding electrochemical properties,as expressed by a specific capacity(689 mAh g^(−1) at 0.1 A g^(−1) after 100 cycles),rate performance(i.e.,448 mAh g^(−1) at 2 A g^(−1)),and longtime cycle stability(523 mAh g^(−1) after 200 cycles at 0.2 A g^(−1)),which are superior to those without LiVO_(2) conductive layer when treated at the same temperature in air.The findings reported in this work may offer novel hints of preparing more advanced anodes and promote the applications of vanadate materials such as Li_(3)VO_(4) for next-generation lithium-ion batteries.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Grant Nos.21571176,21671077,21771075 and 21871106).
文摘Li_(3)VO_(4) is a promising electrode material for next-generation lithium-ion batteries(LIBs)due to its excellent specific capac-ity(592 mAh g^(−1)),suitable discharge voltage(0.5-1.0 V),and moderate volume change upon charge/discharge,while it still suffers from low electronic conductivity that usually gives a poor rate capability,low initial coulombic efficiency,and large polarization,imposing a challenge on its practical applications.In this work,a partial surface phase transformation of Li_(3)VO_(4) was initiated via a freeze-drying method followed by a heat treatment in inert gas.Using this method,Li_(3)VO_(4) was integrated with a conductive layer LiVO_(2) and carbon matrix.The synergistic effect among Li_(3)VO_(4),LiVO_(2) layer,and carbon matrix was systematically studied by optimizing the treatment conditions.When treated at 600°C in Ar,Li_(3)VO_(4)-based composite delivered outstanding electrochemical properties,as expressed by a specific capacity(689 mAh g^(−1) at 0.1 A g^(−1) after 100 cycles),rate performance(i.e.,448 mAh g^(−1) at 2 A g^(−1)),and longtime cycle stability(523 mAh g^(−1) after 200 cycles at 0.2 A g^(−1)),which are superior to those without LiVO_(2) conductive layer when treated at the same temperature in air.The findings reported in this work may offer novel hints of preparing more advanced anodes and promote the applications of vanadate materials such as Li_(3)VO_(4) for next-generation lithium-ion batteries.
