Planar ultrathin flexible high-voltage supercapacitor and preparation method thereof

The invention discloses a planar ultrathin flexible high-voltage supercapacitor and a preparation method thereof. Specifically, ultra-thin flexible metal sheets serve as a conductive series medium, the edges of the adjacent metal sheets are sprayed with polytetrafluoroethylene or coated with high-temperature-resistant epoxy resin AB glue to serve as insulating layers, polymer layers are obtained on the metal sheets by adopting a method of thermocuring polyimide precursor liquid or pasting PI films, the graphene electrode material is prepared through laser processing of the PI curing layers/films, and a hydrogel electrolyte is dispensed on the surface and a copper foil is adhered to serve as a current collector to finish the packaging of the supercapacitor. Due to the series connection effect of the middle thin-layer metal sheets, high voltage above 10V can be output finally; the thickness of the metal sheet and the PI curing layer/film is controllable, so that the design of an ultra-thin series structure can