TECHNOLOGY FOCUS - POLYMERS - Preferred Electrochemical System: The system is a battery, a fuel cell, a capacitor or an electrolyzer. A filler (e.g. alumina powder, titania powder, silica powder, ceria powder, polyolefin powder, polystyrene powder and their acidified derivatives) is optionally included. The non-liquid proton conductor membrane can include crosslinks formed between molecules of the matrix powder and/or the acidic multimer.Preferred Fuel Cell: The second solvent is water formed while the cell operates. The fuel cell, anode plate and cathode plate contain a catalyst selected from platinum, palladium, rhodium, ruthenium, tin, cobalt, chromium, metal phthalocyanines, metaloporphyrins and mixtures.Preferred Battery: The anode plate contains a mixture of a first ingredient selected from chloranilic acid and compounds containing metal ions with a redox potential between -400 to +400 mV versus a standard hydrogen electrode and of a second ingredient selected from acetylene black or carbon (e.g. carbon black and activated carbon). The cathode plate includes a mixture of a third ingredient selected from compounds containing metal ions having a redox potential higher than one volt versus the standard hydrogen electrode, and a fourth ingredient selected from acetylene black or carbon (e.g. carbon black and activated carbon).Preferred Solvent: The first and second solvents are water. The second solvent is added externally to the system.Preferred Polymer: The matrix polymer is of any type which swells when in contact with a selected solvent (including water), e.g. polyvinylidene fluoride, polyhydroxyethlene, polyethyleneimine, polyacrylic acid, polyethylene oxide, poly-2-ethyl-2-oxazoline, polyvinyl alcohol, phenol formaldehyde resins, polyacrylamide, poly-N-substituted acrylamide, poly-4-vinylpyridene, polymethacrylic acid, poly-N-vinylimidazole, polyvinyl sulfonic acid, poly-2-vinylpyridine, polyvinylpyrrolidene, polyvinyl phosphonic acid, agar, agarose, etc., of a mixture of these or others.Preferred Acidic Multimer: The acidic multimer is obtained by acidification of an organic multimer, e.g. polyolefins, polystyrenes, phthalocyanines, porhyrins, nylons, parafin wax and a vinyl polymer or copolymer containing group (-CH2-)n or is obtained by polymerization or copolymerization of suitable monomers such as vinyl sulfonic acid, vinyl phosphoric acid, acrylic acid, methacrylic acid, 2-acrylamido-2-methyl-propylsulfonic acid, styrenesulfonic acid and other vinylmonomers containing an acidic group. The acidic multimer may be in its salt form during the preparation of the membrane. Particularly preferred acidic multimers are sulfonated wax, polyvinylsulfonic acid, polyvinylphosphoric acid, sulfonated polyolefins, sulfonated polystyrenes, sulfonated phthalocyanines, sulfonated porphyrins, poly-2-acrylamido-2-methylpropanesulfonic acid, polyacrylic acid and polymethacrylic acid. EXAMPLE - Preparation of a battery: A solution of polyvinyl alcohol (PVA, 20 g) in water (500 ml) was prepared. 25% aqueous polyvinylsulfonic acid sodium salt (0.6 g) and Dowex 50WX 8 200-400 mesh strongly acidic ion exchager (0.6g) to a portion of the prepared solution (15 ml). The solution was stirred and poured onto a flat surface and dried. The resulting membrane was interposed between two electodes. The anode plate was a mixture of chloroanilic acid and acetylene black, and the cathode plate was a mixture of manganese sulfate and acetylene black, both slightly wetted with 4M sulfuric acid. The cell cycled between 0.8 and 2.0 volts at 4 mA/cm2, and was capable of hundreds of cycles giving an energy density of approximately 40 mWh/cm3, under ambient conditions.