TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The alkali metal salt comprises a lithium salt (preferably Li((C2O4)2B), Li(C2O4)BF2, LiClO4, LiBF4, LiAsF6, LiPF6, LiCF3SO3, Li(CF3SO2)2N, Li(CF3SO2)3C, LiN(SO2C2F5)2, or a lithium alkyl fluorophosphate.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The aromatic compound is of formulae (I)-(IV). The concentration of the redox shuttle in the electrolyte is 0.0005-50 wt.%. The polar aprotic solvent comprises ethylene carbonate, propylene carbonate, dimethyl carbonate; ethyl methyl carbonate; diethyl carbonate; methyl propyl carbonate; ethyl propyl carbonate; dipropyl carbonate; bis(trifluoroethyl)carbonate; bis(pentafluoropropyl)carbonate; trifluoroethyl methyl carbonate; pentafluoroethyl methyl carbonate; heptafluoropropyl methyl carbonate; perfluorobutyl methyl carbonate; trifluoroethyl ethyl carbonate; pentafluoroethyl ethyl carbonate; heptafluoropropyl ethyl carbonate; perfluorobutyl ethyl carbonate; fluorinated oligomers; dimethoxyethane; triglyme; dimethylvinylene carbonate; tetraethyleneglycol; dimethyl ether; polyethylene glycols; sulfones; or gamma -butyrolactone.R1=T1;T1=H, F, Cl, Br, CN, NO2, alkyl, haloalkyl, phosphate or polyether (preferably methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl or tert-butyl);orR1+R2 or R2+R3 or R3+R4=fused ring on the benzene ring;R2=T1 (preferably H or F);R3=T1 (preferably methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl or tert-butyl);R4=T1 (preferably methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, H or F);X' and Y'=a group of formula -(C(R5)(R6))n-(O)p-P(=O)(R7)(R8) (i);Z'=group of formula (ii);R5 and R6=H, F, Cl, Br, CN, NO2, alkyl, haloalkyl, phosphate or polyether;R7 and R8=H, F, Cl, Br, CN, NO2, alkyl, alkoxy, haloalkyl, haloalkoxy, aryl, aryloxy, haloaryl, haloaryloxy or polyether;R9=H, F, Cl, Br, CN, NO2, alkyl, alkoxy, haloalkyl, haloalkoxy, aryl, aryloxy, haloaryl, haloaryloxy or polyether;n=0-8;p=0 or 1.Provided that: when n is 0, then p is 0; and when n is 1-8, then p is 0 or 1. SPECIFIC COMPOUNDS - 12 Compounds are specified as the aromatic compounds (I)-(IV), e.g. phosphoric acid 2,5-di-tert-butyl-4-(diethoxy-phosphoryloxy)-phenyl ester diethyl ester (IA); (2,5-di-tert-butyl-4-(diethoxy-phosphorylmethoxy)-phenoxymethyl)-phosphonic acid diethyl ester; phosphoric acid 2,4-di-tert-butyl-6-(diethoxy-phosphoryloxy)-phenyl ester diethyl ester; (2,4-di-tert-butyl-6-(diethoxy-phosphorylmethoxy)-phenoxymethyl)-phosphonic acid diethyl ester; and phosphoric acid 2,5-di-tert-butyl-4-(diphenoxy-phosphoryloxy)-phenyl ester diphenyl ester.    EXAMPLE - No suitable example given.