Ion-conductive fused-ring quinone polymer, electrode active material and secondary battery

An ion-conductive fused-ring quinone polymer comprising

• recurring units of formula (1) and/or (2) below
• wherein each X is independently a single bond or a divalent group, and Ar1 and Ar2 are each independently an aromatic hydrocarbon ring or an oxygen atom or sulfur atom-containing aromatic heterocycle that forms together with two carbon atoms on a benzoquinone skeleton, wherein said quinone polymer further comprises
• recurring units of formula (4) or (4′) below
• wherein Z is an alkoxy group of 1 to 12 carbon atoms, an alkyl group of 1 to 12 carbon atoms, an alkylthio group of 1 to 12 carbon atoms, an acyl group of 2 to 12 carbon atoms, an alkylamino group of 1 to 12 carbon atoms, a polyalkylene ether group, a polyalkyleneamine group or an aryl group;
• Z′ is —O—(CH2)a—O—, —(CH2)a—, —S—(CH2)a—S—, —C(═O)—(CH2)b—C(═O)—, —NH—(CH2)a—NH—, —O—(R—O)c—, —NH—(R—NH)c— or a phenylene group;
• R is an alkylene group of 1 to 12 carbon atoms;
• the letter a is an integer from 1 to 12, the letter b is an integer from 1 to 10, and the letter c is an integer from 2 to 4.