Ag(x)VOPO(4): A Demonstration of the Dependence of Battery-Related Electrochemical Properties of Silver Vanadium Phosphorous Oxides on Ag / V Ratios.

As a part of our on-going study on silver vanadium phosphorous oxides (Ag(x)V(y)O(z)PO(4)), we report here the first study of the electrochemical reduction of a low Ag/V ratio silver vanadium phosphorous oxide, Ag(0.48)VOPO(4)·1.9H(2)O. Reminiscent of Ag(2)VO(2)PO(4) reduction, in-situ formation of silver metal nanoparticles along with an associated increase in conductivity were observed after reduction of Ag(0.48)VOPO(4)·1.9H(2)O with 0.37 electron equivalents. However, in contrast to our lithium / Ag(2)VO(2)PO(4) cells, our lithium / Ag(0.48)VOPO(4)·1.9H(2)O cells displayed an even higher voltage on discharge and a characteristic multi-plateau voltage profile, where vanadium reduction was the first reduction step.

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