Metal‐Free, Solid‐State, Paperlike Rechargeable Batteries Consisting of Redox‐Active Polyethers

Metal‐free and totally organic based batteries were fabricated from functional polyethers. Aliphatic polyethers, in which 2,2,6,6‐tetramethylpiperidin‐1‐oxyl and viologen were introduced with high density, were used as the cathode and anode active materials, respectively. By stacking nanosheets of the polymers and an imidazolium‐substituted polyether as the electrolyte, a solid‐state cell only 2 μm thick was made. The anion‐type rocking‐chair cell showed reversible charge/discharge even at a high rate of 5 C without adding any solvents or plasticizers. Although the unsealed cell was measured under ambient conditions, no significant side reactions (including self‐discharging and capacity decay) occurred, whereas conventional electrodes are sensitive to air and water in the charged state. The intrinsic plasticity of the polyethers is also compatible with making free‐form, 3D‐printable batteries. Paper thin: Metal‐free, solid‐state, organic‐polymer‐based rechargeable batteries are developed. Redox‐active polyethers that also function as anion conductors are used as nanosheet electrodes to fabricate a device that is only 2 μm thick. No sealing is needed to avoid self‐discharging or degradation of the solid‐state cell, which can be charged/discharged even at a high rate of 5 C.