Sodium Alginate/Zwitterionic Polymer Gel Electrolyte for Integrated All‐Solid‐State Supercapacitors

Abstract

AbstractAll‐solid‐state stretchable supercapacitors (SSSCs) have attracted widespread attention in the wearable and medical fields because of their nontoxic, safe, and environmentally friendly characteristics. In this paper, a dual network hydrogel polymer was synthesized by a one‐pot method, which was constructed from sodium alginate (SA) and zwitterion copolymer of acrylamide (AM) and sulfobetaine methacrylate (SBMA). The dual network hydrogel polymerSAm/P(AM‐co‐SBMA (SASm for short) were immersed in 1 M H2SO4 electrolyte to obtain gel polymer electrolytes (GPEs). Stretchable electrodes were synthesized on the matrix of SASm gels. Non‐integrated all‐solid‐state stretchable supercapacitors (non‐integrated SSSCs), integrated all‐solid‐state supercapacitors (SSCs) and integrated SSSCs were all assembled into the ‘sandwich’ structure. The elongation of the integrated SSSC is the best and reaches 280 %, and its areal capacitance is 1.96 mF/cm2 under a current destiny of 50 μA/cm2, and the capacitance still remains 95 % of the initial value after 10000 charge and discharge cycles, and its energy density is 5.8×10−2 μWh/cm2 at a power density of 2.9×10−2 mW/cm2. This integrated SSSC has excellent cycling stability while maintaining good tensile properties.