Résumé
The electrochemical reaction of lithium with triclinic FeVO4 (a = 6.714(1) Å, b = 8.060(2) Å, c = 9.352(2) Å, α = 96.678(1)°, β = 106.641(1)°, and γ = 101-523(1)°, P-1) has been investigated by means of 57Fe Mössbauer spectroscopy in order to complement the previous X-ray diffraction and X-ray absorption near edge structure studies on the same system. A complex FeIII → FeII → Fe0 or FeIII → FeII ,Fe0 reduction process has been detected upon the first discharge of the battery down to 0.02 V, with in addition the iron reoxidation during the next charge step. A mechanism based on "lithium adsorption" is proposed in order to explain this unexpected behavior.