Silver vanadium phosphorous oxide, Ag_0.48VOPO₄: Exploration as a cathode material in primary and secondary battery applications

Silver vanadium phosphorous oxides (SVPO) have been recently shown to be a promising new class of materials for primary lithium batteries with the synthesis and electrochemical investigation of Ag₂VO ₂PO₄. More recently a second silver vanadium phosphorous oxide, Ag_0.48VOPO₄ · 1.9H₂O, was reported. The investigation reported here provides mechanistic information regarding the reduction mechanism of Ag_0.48VOPO₄ · 1.9H₂O via magnetic susceptibility measurements, quantitative XRD, and the use of galvanostatic intermittent titration (GITT) type tests. Ag _0.48VOPO₄ · 1.9H₂O shows promise as a cathode material for primary cell applications demanding high voltage, state of charge indication, and good pulse performance such as biomedical battery applications. Additionally, the first exploration of electrochemical reversibility of a silver vanadium phosphorous oxide material is reported. Via slow scan voltammetry and ex-situ XRD of both discharged and charged material, Ag_0.48VOPO₄•1.9H₂O shows reversibility of the vanadium center however, little reincorporation of the silver metal produced during the discharge is observed during the charge step.