NOVELTY - A fuel cell system (10) comprises electronic device (11) with housing (14) defining fuel cartridge chamber (16), fuel cartridge (12) receivable in fuel cartridge chamber. The fuel cartridge includes membrane electrode assembly or assemblies, and fuel reservoir containing fuel. The fuel is transportable to the electronic device before being transportable to the membrane electrode assembly for conversion to electricity for use by electronic device.    USE - For use converting chemical energy of reactants into direct current electricity in electronic device, e.g. mobile or cell phones, calculators, power tools, gardening tools, personal digital assistants, digital cameras, laptop computers, computer games systems, portable music system, global positioning system, and camping equipment. When the fuel cartridge is operatively associated with the electronic device, the air chamber is in fluid communication with a cathode of the membrane electrode assembly such that air is transportable to the cathode. When the fuel cartridge is operatively associated with the electronic device the carbon dioxide separator is in fluid communication with anode of the membrane electrode assembly such that a gas byproduct is transportable to the gas product separator. When the fuel cartridge is operatively associated with the electronic device, the condenser is in fluid communication with a cathode of the membrane electrode assembly such that a liquid byproduct is transportable to the condenser. When the fuel cartridge is operatively associated with the electronic device, the mixing chamber is in fluid communication with the condenser and the fuel reservoir such that the fuel is transportable to the mixing chamber and the byproduct is transportable to the mixing chamber and the fuel and the byproduct are mixed then transported to the membrane electron assembly. The metering valve is disposed between and in fluid communication with the condenser and mixing chamber such that the byproduct is transportable to the mixing chamber through the metering valve. The membrane electrode assembly and fuel reservoir are disposable. The membrane electrode assembly is arranged in a stack. The fuel reservoir is removably attached to the cartridge so that the fuel reservoir can be refilled or replaced. The membrane electrode assembly is removably attached to the cartridge, so that the membrane electrode assembly can be repaired or replaced.    ADVANTAGE - The invention provides optimal operations of electronic device. It allows servicing or repairing the PEM without servicing the electronic device.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a fuel cell cartridge adapted to be insertable to an electrical device to supply electricity thereto comprising membrane electrode assembly or assemblies, and a fuel reservoir containing fuel. The fuel is reacted at the membrane electrode assembly to produce electricity and the balance of plant occurs within the cartridge.    DESCRIPTION OF DRAWING(S) - The figure shows the fuel cell system.    Fuel cell system (10)    Electronic device (11)    Fuel cartridge (12)    Housing (14)    Fuel cartridge chamber (16)