Transition metal borate comprising cathode for rechargeable battery

Described is a cathode comprising a conductor and a cathode material said cathode material comprising as electronically active material a transition metal (T) borate (BO 3 ) of formula Li x T I m T II n O y BO 3 in form of nanoparticles, wherein m+n = 1, x = 0 - 3, and y = 0 - 2, and T I and T II are different transition metals, e.g. selected from Ti, V, Cr, Mn, Fe, Ni, Co and Cu. In a specific embodiment, m is 1 and n is 0.