Improvement of solid-state symmetric cell performance with lithium vanadium phosphate

We constructed a Li3V2(PO4)(3)/Li1.5Al0.5Ge1.5(PO4)(3)/Li3V2(PO4)(3) symmetric all solid-state Li-ion battery. Since the rechargeable capacity of Li3+xV2(PO4)(3) anode is lower than that of Li3-xV2(PO4)(3) cathode, the symmetric cell capacity is restricted by the anode capacity. So, the improvement of Li3+xV2(PO4)(3) anode properties was tried using mechanical milling to uniformly mix Li3V2(PO4)(3) and carbon. The charge and discharge capacity of Li3V2(PO4)(3)/C using mechanical milling was greatly increased compared to Li3V2(PO4)(3)/C using hand milling. The structure change with the insertion and extraction of lithium confirmed using ex-situ XRD measurements. The Li extraction/insertion of Li3V2(PO4)(3) with a NASICON structure can proceed to the reversible expansion/contraction of the lattice due to the structural strength and flexibility of NASICON framework with the corner-sharing matrix. The discharge capacity of the all solid-state battery per Li3V2(PO4)(3) in cathode weight achieved 92 mAh g(-1) by good dispersion state of Li3V2(PO4)(3) and carbon using mechanical milling. (C) 2013 Elsevier B.V. All rights reserved.