High voltage and healing flexible zinc ion battery based on ionogel electrolyte

Flexible and multifunctional zinc ion batteries (ZIBs) play an important role in flexible or wearable electronics. Polymer gels with outstanding mechanical stretchability and high ionic conductivity are very promising to be used as electrolytes for the solid-state ZIBs. Herein, a novel ionogel of poly(N,N'-dimethylacrylamide)/zinc trifluoromethanesulfonate (PDMAAm/Zn(CF₃SO₃)₂) is designed and synthesized by UV-initiated polymerization of monomer DMAAm in ionic liquid solvent 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([Bmim][TfO]). The prepared PDMAAm/Zn(CF₃SO₃)₂ ionogels possess high mechanical performance (893.7% tensile strain and 151.0 kPa tensile strength), moderate ionic conductivity (0.96 mS cm^-1) and superior healable performance. The as-prepared ZIBs based on PDMAAm/Zn(CF₃SO₃)₂ ionogel electrolyte assembled by carbon nanotubes (CNTs)/polyaniline as cathode and CNTs/Zn as anode not only exhibit excellent electrochemical properties (up to 2.5 V), flexible and cyclic performance, but also possess good healability for five broken/healed cycles with slight 12.5% performance decay. More significantly, the broken/healed ZIBs exhibit superior flexibility and cyclic stability. This ionogel electrolyte can be extended the flexible energy storage devices for use in other multifunctional portable and wearable energy related devices.