The present disclosure provides the use of a biomolecule, flavin, appended to a polymerizable unit that can then be polymerized to form an electroactive active polymer. The polymer and the flavin unit are comprised of an organic material containing C, H, N, and O atoms. The electroactive functionality is related to the double bonds that are present in the flavin unit that are appended to a non-electroactive backbone. This appended unit is rendered insoluble in the electrolyte of the discussed secondary battery unit. Several different molecular structures are disclosed exhibiting efficacy as energy storage medium in energy storage devices. Compounds have also been synthesized from which these different energy storage molecular structures are produced.