title: A new strategy for synthesizing yolk-shell V₂O₅ powders with low melting temperature for high performance Li-ion batteries.
abstract: This paper presents the fabrication of yolk-shell V₂O₅ powders with a low melting temperature of 690 °C by using a simplified two-step process. The spherical V₂O₃-C composite obtained by spray pyrolysis transforms into yolk-shell V₂O₅ powder by a simple combustion process at 400 °C. The yolk-shell V₂O₅ powders are composed of nanoplate crystals several tens of nanometers in size, and have a BET surface area of 15 m(2) g(-1). The powders exhibit initial discharge and charge capacities of 271 and 264 mA h g(-1) at a current density of 1000 mA g(-1), respectively, and a corresponding Coulombic efficiency of 97.4%. After 100 cycles, the discharge capacity of the yolk-shell V2O5 powders is 201 mA h g(-1). In contrast, spherical V2O5 powders with a dense structure exhibit low initial discharge and charge capacities of 160 and 145 mA h g(-1), respectively. The structural stability of the yolk-shell during Li-ion insertion and extraction improves the electrochemical properties of the V2O5 powders, even at high current densities.
authors.affiliation: Department of Chemical Engineering, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701, Korea. yckang@konkuk.ac.kr.
authors.forename: You Na
authors.initials: YN
authors.lastname: Ko
authors.forename: Yun
authors.initials: Y
authors.lastname: Chan Kang
authors.forename: Seung Bin
authors.initials: SB
authors.lastname: Park
mesh_terms: D011211:Electric Power Supplies; D004566:Electrodes; D007477:Ions / Q000737:chemistry; D008094:Lithium / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry / Q000648:ultrastructure; D010316:Particle Size; D044366:Transition Temperature; D017968:Vanadium Compounds / Q000737:chemistry*
chemical_list: D007477:Ions; D017968:Vanadium Compounds; D008094:Lithium; C066075:vanadium pentoxide