A cathode composition

A cathode material for a battery, wherein the material has an anti-fluorite preferably orthorhombic Pbca crystal structure and belongs to the family represented by the formula Li5Fe(1-x)AlxO4, wherein x is greater than zero and less than or equal to one, preferably 0.1 to 0.25; and a method of making it from stoichiometric mixing of Li2O, LiFeO2 and Al2O3, ball-milling, and heating to consolidate the powders, e.g. to 700°C or up to 1000°C, e.g. for at least 15 hours, and cooling e.g. at at least 5°C per minute. The cathode material is designed for a lithium ion battery to be a cheaper and less toxic alternative to NMCs and such transition metal oxides, with the inclusion of Aluminium in place of Iron improving stability and avoiding incomplete reconstruction of the coordination around iron ions through redox cycles. The higher temperature β Pbca polymorph is stabilized at room temperature and possibly has improved lithium distribution due to greater symmetry than the lower temperature α Pmmm polymorph.