Electrochemical behaviour of amorphous V₂O₅(-P₂O₅) cathodes for lithium secondary batteries

The electrochemical behaviour of amorphous vanadium oxides (a-V₂O₅ and a-V₂O₅-P₂O₅) cathodes in lithium cells has been investigated. The reversibility of the cathodes is superior to that Of c-V₂O₅ and the cathodes can operate for > 300 cycles. The relationship between cathode composition and cycle performance has been determined, and P₂O₅, as a network-former, has been found not to harm the reversibility of cathodes. The degradation in capacity with cycling of the Li/a-V₂O₅(-P₂O₅) system is due to deterioration of the anode, i.e., an increased polarization on discharge.