Structural and electrochemical properties of Fe- and Al-doped Li3V2(PO4)3 for all-solid-state symmetric lithium ion batteries prepared by spray-drying-assisted carbothermal method

Li3V2(PO4)(3) and Li3V1.9M0.1 (PO4)(3) (M = Fe, Al) samples were synthesized via spray-drying-assisted carbothermal solid-state reaction, and their structural and electrochemical properties were investigated by XRD, SEM, and galvanostatic charge/discharge. Li3V2(PO4)(3), Li3V1.9Fe0.1(PO4)(3), and Li3V1.9Al0.1 (PO4)(3) showed initial discharge capacities of 103.3 mAh g(-1), 107.6 mAh g(-1), and 105.6 mAh g(-1), respectively, in the all-solid-state symmetric batteries with Li1.5Al0.5Ge1.5(PO4)(3) solid-state electrolytes at a rate of 7.5 mA g(-1). The enhanced discharge capacities of Fe and Al-doped Li3V2(PO4)(3) could be attributed to the increased electrical conductivity induced by the introduction of Fe3+ or Al3+ trivalent ions into the V3+ sites and to the structural stabilization of the monoclinic Li3V2(PO4)(3) by the spray-drying process. (C) 2015 Elsevier B.V. All rights reserved.