Disordered Rocksalt Material and Method of Forming It

A composition comprising a disordered rock salt having a cation comprised of lithium and at least one other metal and an anion comprised of oxygen having a coating comprised of a metal fluoride, a metal oxyfluoride or combination thereof may be made by a dry or wet method. The methods comprise intermixing a metal fluoride and a disordered rock salt and heating to a temperature to react a metal fluoride with the DRS. The method may form a spinel in addition to the metal fluoride or metal oxyfluoride, when in the presence of a base such as ammonium.