Investigation of stable viologen-based anodes for fully organic batteries with water-based electrolyte

Three different viologen polymers are designed, synthesized, characterized, and applied in thin-film cells. The viologen-based anodes show excellent cycling and calendar stability (up to 2300 cycles and over four months at 1C cycling) against oxidized hydrophilic carbon ( AC-02 ). A new cryogel is also tested as an alternative separator. The cells with cryogel separator demonstrate extremely high cyclic stability (up to 4000 cycles with 1C-rate) and a lower drop in capacity during self-discharge tests (~8% after 72 h). • Viologen polymers for aqueous solid-state thin-film batteries. • 92% capacity retained after 2000 cycles with cryogel separator. • Only 5% capacity loss after 72 h self-discharge.