Synthesis and electrochemical properties of lithium iron oxides with layer-related structures

Two modifications of layered lithium iron oxides were synthesized and characterized by X-ray diffractometry and electrochemical measurements. LiFeO2 with α-NaFeO2 structure was synthesized by the ion-exchange reaction in molten salts; cationic distribution in the host, α-NaFeO2, affects the disordering in the reaction product. However, lithium de-intercalation was not confirmed. The ion-exchange reaction in molten salts gave a whole range of solid solution, Li(Fe1 − xNix)O2, using the α-Na(Fe1 − xNix)O 2 hosts, and their electrochemical properties were determined. Lithium iron oxide, LiFeO2, with a corrugated layer structure, was synthesized by an ion-exchange reaction between γ-FeOOH and LiOH · H2O. Lithium cells consisting of LiFeO2 cathodes and lithium anodes showed good charge and discharge reversibility in the voltage 1.5–3.0 V range.