DMSO-assisted flexible polyacrylamide organohydrogel electrolytes for anti-freezing and high-performance zinc ion battery

Flexible hydrogel-based Zn-ion batteries (ZIBs) are recognized as a prospective energy storage device benefiting from their high security, low price, and competitive electrochemical performance. However, the bad temperature tolerance is one of the drawbacks that seriously hinder the practical utilization of ZIBs based on conventional hydrogel electrolytes. Herein, we developed a dimethyl sulfoxide (DMSO)-doped polyacrylamide (PAM) electrolyte to effectively enhance the low-temperature tolerance. The as-prepared PAM/DMSO organohydrogel exhibits excellent flexibility with a tensile strength of 32.9 kPa at a fracture strain of 1384%, high ionic conductivity of 77.8 mS/cm, and excellent environmental stability up to − 40 °C. The PAM/DMSO organohydrogel was combined with a Prussian blue analog cathode and zinc anode to form a ZIB battery, which showed excellent electrochemical properties with a high specific capacity of 230.3 mAh/g. Significantly, such a device can maintain good cycling and stable electrochemical performance under sub-zero conditions, proving the excellent anti-freezing property of the organohydrogel electrolyte. Besides, the ZIB could retain great electrochemical performance even at severe deformation. Our study offers an inspiring strategy to create stretchable and anti-freezing hydrogel electrolytes for ZIBs with good low-temperature tolerance.