On the use of nonylbenzo-hexaquinone as a substitute for monomeric quinones in non-aqueous cells

Abstract Nonylbenzo-hexaquinone, an insoluble polymer of high theoretical specific capacity (0.489 A h/g), has been used as the cathode material in organic electrolytes instead of benzoquinone and its derivatives. The reduction mechanism is rather complex and involves two main steps, the first of which, as shown by cyclic voltammetry, is, in turn, a multi-process step. It corresponds to the uptake of 6 Li + /molecule or 0.234 A h/g. The second step tends to merge with electrolyte reduction, thus preventing a correct estimate of the total number of Li + involved. The first reduction step is partly reversible (2.0–2.5 e − out of 6), whereas the second is irreversible. 150 cycles were obtained when cycling was performed between 2.0 and 3.5 V at 0.5 mA/cm 2 . A typical energy density during cycling was 127 W h/kg (electrodes only, additives included).