Disclosed is a sheet-like chemical cell including a plurality of unit cells each of which comprises an electrolyte membrane, a plurality of anode plates on one surface of the electrolyte membrane, and a plurality of cathode plates on the other surface of the electrolyte membrane, with the anode and the cathode plates opposed to each other in pairs with the membrane therebetween. Slots are provided in the electrolyte membrane between adjacent anodes and adjacent cathodes, and cathode and anode wiring layers, on thermoplastic sheets, are provided to sandwich the electrolyte membrane. forming a laminate. The laminate is heat-crimped, with wiring layers on both sides of the membrane being electrically connected through the slots, and thermoplastic resin, of the thermoplastic sheets, filling the slots. Also disclosed are methods of making such cells.