NOVELTY - The fuel cell useful for generating electricity, comprises an anode (210) having an anode catalyst, a cathode (220) having a gas diffusion electrode, a cathode catalyst on the gas diffusion electrode and a hydrogel (222) on the cathode catalyst, a channel (240) contiguous with the anode and cathode, and a liquid electrolyte (230) having a fuel in the channel. The hydrogel is present between the anode and the cathode, and comprises an aqueous liquid and a polymer having an acid capacity less than 0.8 meq/g. The polymer comprises no acid groups and base groups covalently bound to the polymer.    USE - The fuel cell is useful for generating electricity and useful in fuel cell stack, power supply device, electronic devices (claimed), portable and mobile fuel cell systems, systems in aerospace vehicles and automotive and aviation systems, where the fuel cells are polymer electrolyte membrane fuel cells, direct methanol fuel cells, alkaline fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells and solid oxide fuel cells and where the electronic devices are cellular phones, laptop computers, DVD players, televisions, personal data assistants (PDAs), calculators, pagers, hand-held video games, remote controls, cassette players, CD players, radios, audio players, audio recorders, video recorders, cameras, navigation systems and wristwatches.    ADVANTAGE - The fuel cell maintains water neutrality without additional weight, parasitic losses and increased system complexity, is physically stable by minimizing the fuel crossover, and has high performance.    DETAILED DESCRIPTION - The fuel cell useful for generating electricity, comprises an anode (210) having an anode catalyst, a cathode (220) having a gas diffusion electrode, a cathode catalyst on the gas diffusion electrode and a hydrogel (222) on the cathode catalyst, a channel (240) contiguous with the anode and cathode, and a liquid electrolyte (230) having a fuel in the channel. The hydrogel is present between the anode and the cathode, and comprises an aqueous liquid and a polymer having an acid capacity less than 0.8 meq/g. The polymer comprises no acid groups and base groups covalently bound to the polymer. The anode comprises first and second surfaces. The hydrogel is in contact with the first surface of the anode, and the channel is in contact with the second surface of the anode. The polymer is a neutral hydrophilic polymer. The aqueous liquid has an osmotic pressure of 1.2 MPa. INDEPENDENT CLAIMS are included for:    (1) a method of generating electricity from the fuel cell;    (2) a cathode for a fuel cell;    (3) a fuel cell stack;    (4) a power supply device; and    (5) an electronic device.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic representation of a fuel cell having a liquid electrolyte and a hydrogel.    Anode (210)    Cathode (220)    Hydrogel (222)    Liquid electrolyte (230)    Channel. (240)