Current research on vanadium oxides in lithium ion batteries （LIBs） considers them as cathode materials, whereas they are rarely studied for use as anodes in LIBs because of their low electrical conductivity and rap...Current research on vanadium oxides in lithium ion batteries （LIBs） considers them as cathode materials, whereas they are rarely studied for use as anodes in LIBs because of their low electrical conductivity and rapid capacity fading. In this work, hydrogenated vanadium oxide nanoneedles were prepared and incorporated into freeze-dried graphene foam. The hydrogenated vanadium oxides show greatly improved charge-transfer kinetics, which lead to excellent electrochemical properties. When tested as anode materials （0.005-3.0 V vs. Li/Li＋） in LIBs, the sample activated at 600℃ exhibits high specific capacity （-941 mA-h-g-1 at 100 mA.g-1） and high-rate capability （-504 mA·h·g-1 at 5 A·g-1）, as well as excellent cycling performance （-285 mA.h.g-1 in the 1,000th cycle at 5A-g-1）. These results demonstrate the promising application of vanadium oxides as anodes in LIBs.展开更多
Lithium-ion battery anode used as silicon particles were obtained from different major suppliers,and they were characterized by different spectroscopic techniques and evaluated by electrochemical experiments.Correlati...Lithium-ion battery anode used as silicon particles were obtained from different major suppliers,and they were characterized by different spectroscopic techniques and evaluated by electrochemical experiments.Correlations between the key physical parameters and electrochemical properties of the silicon particles were investigated.Silicon particle size,surface oxygen content,-OH content and physical appearance are found to strongly influence the electrochemical properties of the Si anode.The particle size of 100 nm has great promise for the practical application of Si nanoparticles in the lithium-ion battery industry.An inverse correlation between the oxygen content and the reversible capacity or first coulombic efficiency was obtained.The-OH content by surface treatment contributes to enhanced cycling stability by the improved affinity between the Si particle and the water-soluble binder.Spherical Si particles perform better compared to irregular particles,and agglomeration dramatically decreases the cycling stability of the Si anode.Among the investigated Si particles,the sample that exhibited a reversible capacity of more than 2500 mAh g^(-1),a first coulombic efficiency of 89.26%and an excellent cycling stability,has great potential for use in the battery industry.展开更多
文摘Current research on vanadium oxides in lithium ion batteries （LIBs） considers them as cathode materials, whereas they are rarely studied for use as anodes in LIBs because of their low electrical conductivity and rapid capacity fading. In this work, hydrogenated vanadium oxide nanoneedles were prepared and incorporated into freeze-dried graphene foam. The hydrogenated vanadium oxides show greatly improved charge-transfer kinetics, which lead to excellent electrochemical properties. When tested as anode materials （0.005-3.0 V vs. Li/Li＋） in LIBs, the sample activated at 600℃ exhibits high specific capacity （-941 mA-h-g-1 at 100 mA.g-1） and high-rate capability （-504 mA·h·g-1 at 5 A·g-1）, as well as excellent cycling performance （-285 mA.h.g-1 in the 1,000th cycle at 5A-g-1）. These results demonstrate the promising application of vanadium oxides as anodes in LIBs.
基金The authors are very grateful to the National Natural Science Foundation of China(NSFC no.21875154 and 21473120)for funding.
文摘Lithium-ion battery anode used as silicon particles were obtained from different major suppliers,and they were characterized by different spectroscopic techniques and evaluated by electrochemical experiments.Correlations between the key physical parameters and electrochemical properties of the silicon particles were investigated.Silicon particle size,surface oxygen content,-OH content and physical appearance are found to strongly influence the electrochemical properties of the Si anode.The particle size of 100 nm has great promise for the practical application of Si nanoparticles in the lithium-ion battery industry.An inverse correlation between the oxygen content and the reversible capacity or first coulombic efficiency was obtained.The-OH content by surface treatment contributes to enhanced cycling stability by the improved affinity between the Si particle and the water-soluble binder.Spherical Si particles perform better compared to irregular particles,and agglomeration dramatically decreases the cycling stability of the Si anode.Among the investigated Si particles,the sample that exhibited a reversible capacity of more than 2500 mAh g^(-1),a first coulombic efficiency of 89.26%and an excellent cycling stability,has great potential for use in the battery industry.
