TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Compound: The dithiolodithiole-containing compound of formula (1) is preferably of formula (2). The dithiolodithiole-containing compound of formula (2) is preferably of formula (3).R5-R8=R1, where R5 and R6, and R7 and R8 optionally bonded to form ring, preferably methyl;andn=2.Preferred Property: The dielectric constant of nonaqueous solvent is 10 or less, solvent is 30 or more, and mixture of nonaqueous solvent and solvent is 10-30. Preferred Components: The electrolyte contains nonaqueous solvent and salt containing anion and cation dissolved in nonaqueous solvent. The solvent having dielectric constant of 10 or less is chosen from chain-shaped carbonate, chain-shaped ester and chain-shaped ether. The solvent having dielectric constant of 30 or more is cyclic carbonate and/or cyclic ether. Preferred Definitions:    R1-R4=H;and    n=1 or 2.    SPECIFIC COMPOUNDS - 4 Dithiolodithiole-containing compounds are disclosed. E.g. 2,5-di-1,3-dithiol-2-ylidene(1,3)dithiolo(4,5-d)(1,3)dithiole, 2-(5-(5-(2H-1,3-dithiol-2-ylidene)-2H,5H-(1,3)dithiolo(4,5-d)(1,3)dithiol-2-ylidene)-2H,5H-(1,3)dithiolo(4,5-d)(1,3)dithiol-2-ylidene)-2H-1,3-dithiole, 2-(5-(5-(4,5-bis(methylsulfanyl)-2H-1,3-dithiol-2-ylidene)-2H,5H-(1,3)dithiolo(4,5-d)(1,3)dithiol-2-ylidene)-2H,5H-(1,3)dithiolo(4,5-d)(1,3)dithiol-2-ylidene)-4,5-bis(methylsulfanyl)-2H-1,3-dithiole and 2-(2H,5H,6H-(1,3)dithiolo(4,5-b)(1,4)dithiin-2-ylidene)-5-(5-(2H,5H,6H-(1,3)dithiolo(4,5-b)(1,4)dithiin-2-ylidene)-2H,5H-(1,3)dithiolo(4,5-d)(1,3)dithiol-2-ylidene)-2H,5H-(1,3)dithiolo(4,5-d)(1,3)dithiole of formula (A).    EXAMPLE - 3-((2-((2-Cyanoethyl)thio)-4-(1,3-dithiol-2-ylidene)cyclopent-1-en-1-yl)thio)propanenitrile (in g) (4.36) and tetrahydrofurane (100 ml) were stirred, and cesium hydroxide aqueous solution (7.8) and methanol (100 ml) were added to reaction mixture and stirred for 30 minutes. Then, zinc chloride (1.6) and tetrabutylammonium bromide (4.2) were added to the reaction solution and stirred for 30 minutes. Then, triphosgene (4.5) was added to the reaction solution and mixed to obtain 5-(1,3-dithiol-2-ylidene)(1,3)dithiolo(4,5-d)(1,3)dithiol-2-one. Then, obtained zinc 5-(1,3-dithiol-2-ylidene)(1,3)dithiolo(4,5-d)(1,3)dithiol-2-one (0.9), bis(1,3-dithiol-2-thione-4,5-dithiolate), butyl chloride, trimethylphosphate (38 ml) and toluene (38 ml) were mixed, stirred, filtered and dried to obtain dimethyl 2-(5-(1,3-dithiol-2-ylidene)(1,3)dithiolo(4,5-d)(1,3)dithiol-2-ylidene)-1,3-dithiole-4,5-dicarboxylate. Then, obtained dimethyl 2-(5-(1,3-dithiol-2-ylidene)(1,3)dithiolo(4,5-d)(1,3)dithiol-2-ylidene)-1,3-dithiole-4,5-dicarboxylate (1.25), hexamethylphosphoric triamide (62.5 ml) and lithium bromide (2.7 ml) were mixed at 70 degrees C for 1 hour, filtered and dried to obtain 2,5-di-1,3-dithiol-2-ylidene(1,3)dithiolo(4,5-d)(1,3)dithiole as positive electrode active material. Then, positive electrode was formed using the obtained positive electrode active material.