Electrochemical cell with a polymer electrolyte and process for producing these polymer electrolytes

An electrochemical cell, comprising:

• a pair of electrodes each having one electrode body made of porous base material which essentially consists of carbon particles held together by a binder and has pores which permit percolation of fluid through the electrode body, and in which the electrode body is charged with a catalyst deposited on the base material;
• a membrane film which is arranged between the electrodes, contacts the two electrode bodies electrochemically, acts as an electrolyte and separator of the electrochemical cell and is made of a hydrophillic, proton-conducting polymer material, an interlayer being provided between the membrane film and the base material with the catalyst deposited thereon;
• means for introducing a fluid into at least one of the electrodes;
• means for passing out a fluid from at least one of the electrodes;
• and
• means for making electrical contact with the electrodes;
• the material of the membrane film being a base polymer radiation-grafted with terminally sulphonated vinyl radicals;
• the base polymer being selected from the group formed by substituted and unsubstituted polyolefins, substituted and unsubstituted vinyl polymers and their copolymers;
• the vinyl radicals being derived from vinyl monomers which are selected from the group formed by substituted and unsubstituted vinyl monomers;
• the interlayer comprises a proton-conducting hydrophillic copolymer of poly(perfluoroalkylene) which is substituted with ion-exchanging groups, and poly(perfluoroalkylene) which is substituted with non-ion-exchanging groups;
• and
• the interlayer being applied to the membrane film.