High-capacity proton battery based on π-conjugated N-containing organic compound

Aqueous proton batteries (APBs) have tremendous potential in the energy storage field. Currently, high-performance electrode materials need to be urgently exploited to satisfy the development of APBs. Here, we introduce a π-conjugated N-containing organic compound (diquinoxalino [2,3-a:2',3'-c] phenazine, HATN) with abundant active sites as the anode. By assembling HATN with a β-MnO2 cathode, we produce a high-capacity proton battery with a reversible specific capacity of 260 mAh g−1 at 0.1 A g−1 and an excellent energy density up to 118 Wh kg−1. The high performance is found to result from the abundant C=N moieties and the π-conjugated structure of HATN, which assure the capability of reversible H+ storage and the corresponding stability.