Patent ID: 10193134

Abstract:
A sodium transition metal cathode material for a rechargeable sodium battery having a P2 layered bronze crystal structure, comprising at least 55 mol % manganese, wherein the manganese valence state is at least 3.75. The material undergoes a structural transformation to a secondary cathode material by extraction of sodium during the 1st charge of a rechargeable sodium battery comprising the sodium cathode material. The material has either a composition NaxMO2 where M=Mn1-y-zLiyAz where z<0.2 and y<0.33 and 0.66<x<0.95, and wherein A consists of either one of more elements of the group Ti, Fe, Ni, Mg and Co, or a composition NaxMO2 where M=LiaMn1-a-b-cMgbAc where 0<a<0.2, c<0.2 and 0.2<a+b<0.46 and 0.66<x<0.95, and wherein A consists of either one of more elements of the group Ti, Fe, Ni and Co.