Patent ID: 7722993

Claim:
A secondary solid state current source comprising an anode (An 0 ) made of a metal or an alloy forming via fluorination a fluoride or fluorides, an electrolyte made of a solid fluoride-ion conductor; and a solid cathode (KtF 0 ) based on a fluoride or a solid solution of fluorides with an isobar formation potential lower than an isobar formation potential of the fluoride or fluorides formed on the anode by the fluorination; wherein cathode discharge reaction is KtF 0 +e − →F − +Kt′; wherein anode discharge reaction is An 0 +F − →An′F+e − ; wherein the cathode is reversible with respect to fluorine-ions in a charge-discharge cathode reaction KtF x 0 +Xe 31 XF − +Kt′ under voltages less than decomposition voltage of the electrolyte; wherein the anode is reversible with respect to fluorine ions in a charge-discharge anode reaction An 0 +XF − An′F x +Xe − under voltages less than decomposition voltage of the electrolyte; and wherein the anode, the electrolyte and the cathode comprise at least one component preventing destruction of the secondary solid state current source during the charge/discharge.