An electrolyte solution comprising: (i) a solvent; (ii) an electrolyte salt; (iii) at least one compound (X) of formula : R 21 R 22 N-SO 3 M 21 wherein M 21 is at least one of Li, Na, K, and Cs; and R 21 and R 22 each independently are C 1-6 -alkyl, C 2-6 -alkenyl, or C 2-6 -alkynyl, each linear or branched; C 3-6 -cycloalkyl; C 3-6 -cycloalkenyl or C 3-6 -alkylsilyl; and the alkyl, cycloalkyl and alkylsilyl group each optionally contain a halogen atom substituting a hydrogen atom binding to a carbon atom, and optionally have a cyclic structure; and R 21 and R 22 optionally bind to each other to form a cyclic structure; and (iv) at least one organosilicon compound of any of the formulae and : (R 31 ) n31 -M 31 -O-SiR 32 R 33 R 34 R 41 R 42 R 43 -Si-F wherein M 31 is a metal atom, P, B or P=O; R 31 each independently is C 1-11 -alkyloxy, silyloxy or C 1-11 -alkylsilyloxy; n 31 is the number of R 31 s binding to M 31 , and is the oxidation number of M 31 minus 1 or the oxidation number of M 31 minus 3; R 32 -R 34 each independently are C 1-11 -alkyl, C 2-11 -alkenyl, C 1-11 -alkyloxy or C 6-11 -aryl, and R 41 -R 43 each independently are C 1-11 -alkyl, C 2-11 -alkenyl, C 1-11 -alkyloxy or C 6-11 -aryl. (i) a solvent; (ii) an electrolyte salt; (iii) at least one compound (X) of formula : R 21 R 22 N-SO 3 M 21 wherein M 21 is at least one of Li, Na, K, and Cs; and R 21 and R 22 each independently are C 1-6 -alkyl, C 2-6 -alkenyl, or C 2-6 -alkynyl, each linear or branched; C 3-6 -cycloalkyl; C 3-6 -cycloalkenyl or C 3-6 -alkylsilyl; and the alkyl, cycloalkyl and alkylsilyl group each optionally contain a halogen atom substituting a hydrogen atom binding to a carbon atom, and optionally have a cyclic structure; and R 21 and R 22 optionally bind to each other to form a cyclic structure; and M 21 is at least one of Li, Na, K, and Cs; and R 21 and R 22 each independently are C 1-6 -alkyl, C 2-6 -alkenyl, or C 2-6 -alkynyl, each linear or branched; C 3-6 -cycloalkyl; C 3-6 -cycloalkenyl or C 3-6 -alkylsilyl; and the alkyl, cycloalkyl and alkylsilyl group each optionally contain a halogen atom substituting a hydrogen atom binding to a carbon atom, and optionally have a cyclic structure; and R 21 and R 22 optionally bind to each other to form a cyclic structure; and (iv) at least one organosilicon compound of any of the formulae and : (R 31 ) n31 -M 31 -O-SiR 32 R 33 R 34 R 41 R 42 R 43 -Si-F wherein M 31 is a metal atom, P, B or P=O; R 31 each independently is C 1-11 -alkyloxy, silyloxy or C 1-11 -alkylsilyloxy; n 31 is the number of R 31 s binding to M 31 , and is the oxidation number of M 31 minus 1 or the oxidation number of M 31 minus 3; R 32 -R 34 each independently are C 1-11 -alkyl, C 2-11 -alkenyl, C 1-11 -alkyloxy or C 6-11 -aryl, and R 41 -R 43 each independently are C 1-11 -alkyl, C 2-11 -alkenyl, C 1-11 -alkyloxy or C 6-11 -aryl. M 31 is a metal atom, P, B or P=O; R 31 each independently is C 1-11 -alkyloxy, silyloxy or C 1-11 -alkylsilyloxy; n 31 is the number of R 31 s binding to M 31 , and is the oxidation number of M 31 minus 1 or the oxidation number of M 31 minus 3; R 32 -R 34 each independently are C 1-11 -alkyl, C 2-11 -alkenyl, C 1-11 -alkyloxy or C 6-11 -aryl, and R 41 -R 43 each independently are C 1-11 -alkyl, C 2-11 -alkenyl, C 1-11 -alkyloxy or C 6-11 -aryl. <EOS>