Organic Hydronium-Ion Battery with Ultralong Life

The nonmetallic charge carrier hydronium (H3O+) possesses the advantages of cost-efficiency and high ionic conductivity. However, only several available electrode materials have been reported for reversibly storing H3O+, and most of them suffer from limited cycle life due to the soluble and/or structurally unstable nature. Herein, we demonstrate that an organic quinone dibenzo[b,i]thianthrene-5,7,12,14-tetraone (DTT) exhibits the capability to accommodate H3O+ in an acid electrolyte, with a capacity of 212 mAh gDTT–1 at 0.05 A gDTT–1 and long-term cycling stability. Theoretical calculation results indicate that DTT undergoes a two-electron and subsequent one-electron redox process during reversible storage of H3O+. When coupling with an MnO2 cathode, the constructed MnO2//DTT battery provides long cycling stability over 50000 cycles at 2 A gDTT–1 with a capacity retention of 72%. Furthermore, the battery can operate well and shows cycle stability even at −70 °C, implying promising prospective capability in low-temperature environments.