Enhanced Stability-Based Hydroxymethyl Cellulose/Polyacrylamide Interpenetrating Dual Network Hydrogel Electrolyte for Flexible Yarn Zinc-Ion Batteries

As the field of wearable electronics continues to boom, the demand for flexible energy storage devices continues to grow. However, the development of soft energy supply devices with excellent stability is still a challenging task. Traditional hydrogel electrolytes are prone to mechanical deformation, which makes it difficult to maintain the functional stability of flexible yarn due to its short battery life and low wear resistance. Here, we developed a reversible energy-dissipating dual-network hydrogel electrolyte. The hydroxymethyl cellulose (CMC)/polyacrylamide (PAM) hydrogel electrolyte has a tensile deformation of 2700% and a high ionic conductivity of 6.37 x 10-2 S cm-1. The specific capacity of the assembled CMC/PAM-based yarn cell was 170 mu Ah cm-1 at 1 mA cm-1 and 73.14% after 100 cycles. The excellent performance is attributed to the crosslinked double network structure, in which the introduction of carboxyl groups is conducive to the improvement of hydrophilicity and ionic conductivity. The hydrogen bond and reversible CMC macromolecular chain can be restored after stress relief, which greatly improves the toughness of the material. Even under different bending angles and repeated bending conditions, zinc yarn batteries still have outstanding mechanical properties and cycle stability (71.28% specific capacity after 100 cycles), showing broad application prospects in wearable smart textiles. CMC/PAM double-network hydrogel electrolyte was prepared by radical polymerization.The mechanical and electrochemical properties of Flexible yarn zinc-ion batteries were discussed.The hydrogel has tensile deformation (2700%) and ionic conductivity of 6.37 x 10-2 S cm-1.The specific capacitance of CMC/PAM-based yarn cells at 1 mA cm-1 is 170.23 mu Ah cm-1, and the capacitance is 73.14% after 100 cycles.The durability and flexibility of zinc-ion yarn batteries have been studied.