There is provided a manganese oxide material, wherein the material comprises a host material Q.sub.qMn.sub.yM.sub.zO.sub.x, where Q and M are each any element, y is any number greater than zero, and q and z are each any number greater than or equal to zero, and at least one dopant substituted into the host material, the manganese oxide material having a layered structure in which the ions are arranged in a series of generally planar layers, or sheets, stacked one on top of another. In a particularly preferred material Q is Li and M is either Co, Ni, Al, or Li. Particularly preferred combinations of M and a dopant are Ni,Co; Al,Co; Li,Cu; Li,Al; and Li,Zn. A method of preparing the material is also disclosed.