Electrode material including a complex oxide of lithium and a transition metal

The material has particles or particulate aggregates of a complex Li iM mM m.Z zO oN nF foxide, where M is a transition metal, M is a metal other than the transition metal, Z is a non-metal, and coefficients i, m, m, z, o, n and f are selected such that the complex oxide is electrically neutral, with i = 0, m greater than 0, z = 0, m` =0, o greater than 0, n = 0 and f = 0. A part of the particle or particulate aggregate surface is coated with a carbon layer bound by chemical bonds and/or physical bonds to the carbon. The carbon has covalently bonded functional groups. Independent claims are also included for the following: (1) a method of preparing a material (2) a method of melting an electrode.