Nitro-subsituted aromatic compounds for use in electrodes

A secondary battery comprising a secondary battery cathode,

• wherein the secondary battery cathode is free of electroactive sulfur-containing material and comprises as a cathode active material a nitro-substituted aromatic compound, and
• wherein the nitro-substituted aromatic compound is of formula (I), (II), (III), or (IV)
• or a copolymer comprising repeat units of formula (III) and/or (IV),
• wherein:
• A represents an arene or heteroarene,
• B represents an aromatic carbon allotrope, which is optionally doped with one or more heteroatoms,
• R1 represents one or more -L-NO2 substituents,
• wherein in case that the nitro-substituted aromatic compound is of formula (I), R1 represents at least two -L-NO2 substituents;
• R2 represents N—, ═CH—, or ═CR5—, and
• R3 and R4 independently represent a hydrogen atom or R5,
• wherein A and B are optionally further substituted by one or more R5,
• wherein L represents a covalent bond or a linking group, and
• wherein each —R5 independently represents R6, —X, —NH2, —NR6H, —NR62, —CN, —CHO, —COOH, —COOR6, —COO−M+, —OH, —OR6, or —O−M+, in which:
• R6 represents an alkyl, aryl, or heteroaryl group, M represents a metal ion, and X represents a halogen atom.