Electric Eel‐Inspired Soft Electrocytes for Solid‐State Power Systems

Abstract As the demand for power systems, including portable ones, is growing at an ever‐faster pace, many studies are approaching to discover innovative materials for current battery technology or replace the existing ones with new systems through mimicking living things or nature. Here, a soft, solid‐state power storage system featuring electric eel‐inspired artificial electric organs capable of converting the chemical potential of an ionic gradient into electricity is introduced. These organs are constructed through the assembly of low and high ion‐concentrated zwitterionic gel films with cation‐ and anion‐selective intermembranes, which generate a rechargeable open‐circuit voltage of ≈135 mV. Combined use of a chemically synthesized room‐temperature ionic liquid and a high‐boiling point organic solvent as ion‐conducting electrolyte allows electric organs to withstand extreme temperatures ranging from −20 and 100 °C, while the thin and stretchable constituent layers facilitate mechanical flexibility without compromising electrical performance. Scalable integration of electric organs in series and parallel configurations achieves high levels of voltage and current outputs, and employment of origami folding geometry enables on‐demand discharge upon self‐registered folding, paving the way for portable, high‐voltage energy sources in the fields of wearable electronics and soft robotics.