Nitroxide-substituted polyether as a new material for batteries

Nitroxide-substituted polyether was synthesized as a cathode-active material for a secondary battery. Anionic ring-opening polymerization of a TEMPO-bearing glycidyl ether was carried out under bulk conditions to yield the corresponding polymer with the molecular weight of >10⁴. The obtained polymer was insoluble, but slightly swollen in the electrolyte solution (ethylene carbonate/propylene carbonate). The test cell fabricated with a carbon composite cathode of this radical polymer displayed a plateau voltage at 3.5 V vs. Li/Li⁺. The cell performance was maintained even with a higher amount of the radical polymer loaded in the composite electrode, which could be ascribed to the flexible and rubbery polyether backbone and its higher compatibility with the electrolyte solution.