High performance Li3V2(PO4)3/C composite cathode material for lithium ion batteries studied in pilot scale test

Li(3)v(2)(PO4)(3)/C composite cathode material was synthesized via carbothermal reduction process in a pilot scale production test using battery grade raw materials with the aim of studying the feasibility for their practical applications XRD FT-IR XPS CV EIS and battery charge-discharge tests were used to characterize the as-prepared material The XRD and FT-IR data suggested that the as-prepared Li3V2(PO4)(3)/C material exhibits an orderly monoclinic structure based on the connectivity of PO4 tetrahedra and VO6 octahedra Half cell tests indicated that an excellent high-rate cyclic performance was achieved on the Li3V2(PO4)(3)/C cathodes in the voltage range of 3 0-4 3 V retaining a capacity of 95% (96 mAh/g) after 100 cycles at 20C discharge rate The low-temperature performance of the cathode was further evaluated showing 0 5C discharge capacity of 122 and 119 mAh/g at -25 and -40 C respectively The discharge capacity of graphite//Li3V2(PO4)(3) batteries with a designed battery capacity of 14 Ah is as high as 109 mAh/g with a capacity retention of 92% after 224 cycles at 2C discharge rates The promising high-rate and low-temperature performance observed in this work suggests that Li3V2(PO4)(3)/C is a very strong candidate to be a cathode in a next-generation Li-ion battery for electric vehicle applications (C) 2010 Elsevier Ltd All rights reserved