Process for making electrode foils for galvanic cells

摘要

Electrode films for lithium batteries are produced by using vinylidene fluoride/hexafluoropropylene (VDF/HFP) copolymer with an HFP content of less than 8 wt.% to make a solution, mixing this with electrochemically-active material, drawing out the paste to form a film and then laminating with a polyolefin separator precoated with the same copolymer. A method for the production of electrode films for galvanic elements with lithium-intercalating electrode(s) consisting of a mixture of at least two fluorinated copolymers with polymer-insoluble, electrochemically-active materials finely dispersed in the polymer matrix. The method involves mixing a solution of fluoro-copolymer in a solvent with the active material, drawing out the paste obtained to form a film and then laminating the film with a polyolefin separator which is precoated with the same copolymer. The polymers used are poly-(vinylidene fluoride/hexafluoropropylene) (VDF/HFP) copolymers with an HFP content of less than 8 wt.%. An Independent claim is also included for galvanic elements with electrode films made by this method.