Patent ID: 7615312

Claim:
A rechargeable lithium-ion cell comprising: (a) a positive electrode having a recharged potential and comprising LiFePO 4 , Li 2 FeSiO 4 , Li x MnO 2 (where x is about 0.3 to about 0.4), or MnO 2 ; (b) a negative electrode; (c) a charge-carrying electrolyte comprising a charge carrying medium comprising a charge carrying medium that includes an organic carbonate and a lithium salt; and (d) a cyclable redox chemical shuttle comprising 10-methyl-phenothiazine, 10-ethyl-phenothiazine, 3-chloro-10-ethyl-phenothiazine, 10-isopropyl-phenothiazine, 2-perfluoromethyl-phenothiazine, 10-acetyl-phenothiazine 2-cyano-10-perfluoromethylsulfonyl-phenothiazine, 2-methoxy-10-perfluoromethylsulfonyl-phenothiazine, 2-perfluoromethyl-10-perfluoromethylsulfonyl-phenothiazine, 10-perfluoromethyl-phenothiazine, 10-perfluoromethylsulfonyl-phenothiazine, 10-(1,1,1,2,3,3)-hexafluoropropyl-phenothiazine, or mixtures thereof, wherein the recharged potential is the potential at which the positive electrode becomes delithiated during the first charge cycle to a lithium level corresponding to at least 90% of the available recharged cell capacity.