Novel cathode materials for lithium ion batteries were synthesized via lithium for sodium ion exchange from the known compounds, β-NaFeO2 and NaFeTiO4. The resulting lithium analogs of these known sodium compounds, T-LiFeO2 and LiFeTiO4, contain tunnel-like structures that were characterized using Rietveld refinement of Powder X-ray diffraction, electrochemical measurements, Mössbauer spectroscopy, thermogravimetric analysis, and inductively coupled plasma spectroscopy. Similarly characterized, α- and β-NaFe2O3, with a double layered rock salt structure, were synthesized for the first time as a bulk powder using an oxygen pressure regulation method that provided the appropriate conditions for the two polymorphs to form. Further, investigation into T-LiFeO2 and NaFe2O3 by doping other transition metals into the iron position, to control specific properties of the two materials was performed with success. T- T-LiFeO2 and the parent phase, β-NaFeO2, were doped with up to 0.1 and 0.15 parts of cobalt per formula unit respectively. NaFe2O3 was successfully doped with cobalt up to 0.5 moles with pure phases of both the α-NaFe1.5Co0.5O3 and β-NaFe1.5Co0.5O3 forming. Manganese doping into NaFe2O3 also showed the formation of the $alpha;- phase. Probing the Fe3+/4+ redox potential of both T-LiFeO2 and LiFeTiO4 resulted in the decomposition of each. The cobalt doped T-LiFeO2 though did show a greater possibility of cycling at Fe3+/4+ redox potential, but also resulted in a reaction with the organic electrolyte. Chemical deintercalation of T-LiFeO2 and LiFeTiO4 were performed with resulting in the decomposition of LiFeTiO4. T-LiFeO2, indicated successful lithium deintercalation with preliminary Mössbauer results illustrating Fe4+ formation. Both LiFeTiO4 and T-LiFeO2 successfully cycled electrochemically at the Fe2+/3+ redox potential, with the new calcium ferrite structure polymorph LiFeTiO4 cycling 17 % higher capacity than the previously reported spinel and rock salt structure compounds.
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