Stable all-solid-state potassium battery operating at room temperature with a composite polymer electrolyte and a sustainable organic cathode

The safety issues of potassium battery with nonaqueous electrolytes restrict its practical applications. On the other side, the active material dissolution of organic electrodes deteriorates the performance of organic batteries. As an alternative, all-solid-state potassium batteries comprising the cathode materials of organic compounds can solve the mentioned problems. We herein succeed in demonstrating an all-solid-state potassium battery based on 3,4,9,10-perylene-tetracarboxylicacid-dianhydride (PTCDA) and solid polymer electrolyte(SPE) for the first time. The Poly (propylene carbonate) (PPC)-KFSI with cellulose nonwoven backbone SPE (PPCB-SPE) delivers an ionic conductivity of 1.36 × 10−5 S cm-1 at 20 °C. Furthermore, PTCDA cathode in all-solid-state battery provides an average discharge voltage of 2.3 V, a high initial capacity of 118 mA h g-1 at 10 mA g−1 and a stable cycling performance, showing favorable expectation for the commercial application.