A Graphite∥PTCDI Aqueous Dual‐Ion Battery

A full cell chemistry of aqueous dual‐ion battery (DIB) was reported, comprising the graphite cathode and 3,4,9,10‐perylenetetracarboxylic diimide (PTCDI) as the anode. This DIB employed a mixture aqueous electrolyte: 5 m tributylmethylammonium (TBMA) chloride plus 5 m MgCl2, where [MgCl3]− and TBMA+ serve as the charge carriers for cathode and anode of the DIB, respectively. This novel full cell exhibited a specific capacity of around 41 mAh g−1 based on the total active mass of both electrodes with an average operation voltage of 1.45 V and stable cycling for 400 cycles. Energy storage: An aqueous concentrated electrolyte comprising 5 m MgCl2 and 5 m tributylmethylammonium chloride (TBMACl) is demonstrated to construct a graphite∥3,4,9,10‐perylenetetracarboxylic diimide (PTCDI) full cell dual‐ion battery. The addition of TBMACl into saturated aqueous MgCl2 solution renders the formation of [MgCl3]−, which serves as an active charge carrier for the graphite cathode. Reversible storage of bulky TBMA+ in the PTCDI anode is observed. A full cell delivers the initial reversible capacity of 41 mAh g−1 based on the mass of both electrodes and shows stable cycling over 400 cycles.