Electrochemical Behavior of LiFePO4 in Aqueous Lithium Hydroxide Electrolyte

The electrochemistry of olivine-type iron phosphate (FePO4) as a battery cathode material, in aqueous lithium hydroxide (LiOH), has been investigated. The material forms intercalated LiFePO4 reversibly on electroreduction/oxidation. The formation of Fe3O4 phase, in addition to the regeneration of FePO4 during reverse oxidation of LiFePO4, also occurs. In this regard, the mechanism of FePO4 discharge/charge in aqueous LiOH differs from that in non-aqueous solvents.