The present invention relates to a rechargeable power source comprising a flexible supercapacitor and a charge connection unit. The flexible supercapacitor comprises an electrolyte sandwiched between nickel foams electrodeposited with a nanocomposite. The nanocomposite comprises of a conducting polymer, graphene oxide and a metal oxide. The charge connection unit comprises a microcontroller having an electrical connection line connecting an energy collecting unit with the flexible supercapacitor.