A carbon-based electrode includes activated carbon, carbon black, and a binder. The binder is fluoropolymer having a molecular weight of at least 500,000 and a fluorine content of 40 to 70 wt. %. A method of forming the carbon-based electrode includes providing a binder-less conductive carbon-coated current collector, pre-treating the carbon coating with a sodium napthalenide-based solution, and depositing onto the treated carbon coating a slurry containing activated carbon, carbon black and binder.