Sandwich Configuration of Zinc Anode, Gel Electrolyte, and Radical Polymer Cathode for Fully Stretch-Rechargeable Battery

Over the past decade, there is gradual development in fully stretchable semiconductors. However, to bring these devices to market, they require a reliable built-in power source that can maintain stable output voltage, charge/discharge capabilities, and cycle life. Unfortunately, complex cell configurations have hindered the development of stretchable batteries. To overcome this, a fully stretch-rechargeable battery with a sandwich configuration is fabricated. The cathode layer comprises electrically conductive poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and a redox-active TEMPO-substituted polymer, while the anode consists of a carbon nanotube layer deposited with zinc metal. By sandwiching a hydrogel between these two layers, a rechargeable battery is created that is attachable to human skin and <40 mu m thick. This thin device offers a promising voltage of 1.8 V and is robust against repeated stretching, liquid leakage, and self-discharging reactions induced by oxygen. This study is expected to open up new horizons for e-skin and stretchable electronic fields.