Ra. Leising et al., SOLID-STATE CHARACTERIZATION OF REDUCED SILVER VANADIUM-OXIDE FROM THE LI SVO DISCHARGE REACTION/, Inorganic chemistry, 33(25), 1994, pp. 5733-5740
The reduction of silver vanadium oxide (SVO, AgV2O5.5) by lithium was
studied via the solid-state characterization of the reduced cathode ma
terial. LixAgV2O5.5 products were isolated over a range of 0 < x < 3.3
, with corresponding voltages vs Li ranging from +3.25 to +1.8 V. X-ra
y powder diffraction analysis showed that the SVO materials lose cryst
allinity over the range 0 < x < 1.2, with the simultaneous formation o
f elemental silver. In addition, the c lattice parameter for the sampl
es decreased linearly from 7.56 to 6.55 Angstrom over the range of 0 <
x < 3.3, indicating significant structural changes in the lithiated m
aterial. DSC and resistivity measurements also suggested structural ch
anges in these products. The oxidation states of the vanadium and silv
er components were assigned on the basis of chemical: analysis and X-r
ay powder diffraction results and were consistent with the results of
FT-IR and room-temperature magnetic susceptibility measurements. Volta
mmetry of Li/SVO cells displayed multiple, waves, which correlated wit
h the results of the physical characterization studies. These experime
nts indicated that the reduction of SVO in lithium batteries can produ
ce mixed-valent materials, with the presence of vanadium(V), -(IV) and
-(III) possible in the same sample.