TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The separator is an ion-exchange membrane. The active material is a compound having radical in oxygen atom, nitrogen atom or carbon atom, preferably nitroxy radical compound of formula: R1-N(-R2)-O. (1), oxygen radical compound of formula: R3-O. (2), carbon radical compound of formula: R4-C.(-R5)-R6 (3), compound of formula (4) having radical on verdazyl group, compound of formula: R11-N(-R12)-N.-R13 (5) having radical on hydrazyl group, compound of formula (6) having amino triazine structure, and radical compound of formulae (7-10).R1,R2,R4-R16=linear, branched or cyclic (un)saturated aliphatic hydrocarbyl, aromatic hydrocarbyl, hydroxy, formyl, carboxyl, alkoxy, alkoxycarbonyl, cyano, nitro, nitroso, amino, hetero atom, halo or H, where R1 and R2, R4-R6, R7-R10, R11-R13 and R14-R16 optionally forms ring;R3=optionally substituted aromatic hydrocarbyl;andR17-R19=H, heteroatom, aromatic hydrocarbyl, or linear, cyclic or branched (un)saturated aliphatic hydrocarbyl, where R17-R19 optionally forms ring.R1 and R2, R4-R6, R7-R10, R11-R13, R14-R16 and R17-R19 optionally have substituent, when R1 and R2, R4-R6, R7-R10, R11-R13, R14-R16 and R17-R19 are aliphatic hydrocarbyl and aromatic hydrocarbyl groups. R1 and/or R2 have 2 or more nitroxy radicals in 1 molecule, when R1 and/or R2 are coupled with R1 and/or R2 of 1 or more other molecules. R3 has 2 or more oxy radical in 1 molecule, when R3 is coupled with R3 of 1 or more other molecules. Any one of R4-R6 have 2 or more carbon radicals in 1 molecule, when any one of R4-R6 are coupled with any one of R4-R6 of 1 or more other molecules. Any one of R7-R10 have 2 or more verdazyl groups having radical in 1 molecule, when any one of R7-R10 are coupled with any one of R7-R10 of 1 or more other molecules. Any one of R11-R13 have 2 or more hydrazyl groups having radical in 1 molecule, when any one of R11-R13 are coupled with any one of R11-R13 of 1 or more other molecules. Any one of R14-R16 have 2 or more amino triazine structure having radical in 1 molecule, when any one of R14-R16 are coupled with any one of R14-R16 of 1 or more other molecules.