context: Second, the electrode capacity was calculated (eqn (4)) to be 453 mA h g−1 and third, by integrating the potential profile (eqn (5)), the gravimetric electrode energy density was estimated to be 570 W h kg−1. Both values are here for the organic redox-active part (AQ4), while if we take into account the entire electrode (AQnC72), we arrive at significantly more modest values: 222 mA h g−1 and 279 W h kg−1 (Table S8†). Neither of these measures are totally fair to be compared with traditional electrodes as we also assume a role as current collector for the graphene. With this caveat, the former measure provides twice the experimentally measured capacity of pure AQ, reported to be 217 mA h g−1 ( ) and a theoretical gravimetric energy density comparable to the cathode active materials LiFePO4 (544 W h kg−1) and LiMn2O4 (548 W h kg−1).
answer: LiFePO4 