NOVELTY - The cartridge (100) has a hydrogen permeable membrane (125) placed between chemical hydride hydrogen generating fuel (120) and a perforated opening layer in a metal or plastic case (115). A spring loaded slidable valve plate is positioned adjacent to the perforated opening layer to form a gate valve (110) to be biased in a closed position to prevent hydrogen from escaping from the cartridge. A pin is coupled to a slidable/moveable valve portion (135) to move the slideable valve portion responsive to an actuator. A sealing unit seals the cartridge when inserted into a power generator.    USE - Cylindrical hydrogen generating fuel cartridge for a fuel cell system or battery of a portable electronic equipment i.e. hand-held mobile device.    ADVANTAGE - The cartridge can be consumed at an anode of a fuel cell when oxygen in an ambient airflow is consumed at a cathode of the fuel cell such that the fuel cell can produce water vapor, while reacting hydrogen, oxygen and electricity, so that water vapor can be returned to the cartridge for use in generating more hydrogen when the cartridge includes a source of water vapor in a form of a water reservoir or passage to ambient with a suitable membrane, thus preventing hydrogen from escaping to ambient. The cartridge allows fuel to be formed in a hydraulic press with a die and to contain particle size in a range of 1 to 100 micro-meter, so that particles can be of same size and can include different ranges, while limiting the particle sizes outside of the range, thus improving performance of hydrogen generation and utilization of the fuel in a quick manner. The cartridge allows lubricant i.e. light oil, to be applied between fixed and moveable valves, thus reducing friction and improving sealing. The cartridge allows a gate valve to be normally closed to prevent atmospheric gases from reaching the fuel when the cartridge is not inserted into the fuel cell system, thus achieving consumer safety and regulatory requirements for the cartridge.    DETAILED DESCRIPTION - The hydrogen permeable membrane is a vapor permeable liquid impermeable membrane. The sealing unit is O-ring (155). An INDEPENDENT CLAIM is also included for a method for operating a hydrogen generating fuel cartridge.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of a cylindrical hydrogen generating fuel cartridge with a spring loaded slidable valve.    Cylindrical hydrogen generating fuel cartridge (100)    Gate valve (110)    Metal or plastic case (115)    Chemical hydride hydrogen generating fuel (120)    Hydrogen permeable membrane (125)    Slidable/moveable valve portion (135)    O-ring (155)