TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The reactant fuel material includes a stabilized alkali metal that includes sodium silicide or sodium silica gel, and optionally a coreactant. The aqueous solution includes water (199).    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The water feed tray includes: a spring assembly configured to pressurize the aqueous solution in the water feed tray; an access door configured to receive the aqueous solution; a spring assembly configured to pressurize the aqueous solution in the water feed tray; and a normally closed valve configured as a check valve (140) to regulate pressure of the pressurized aqueous solution delivered to the fuel cartridge, and to prevent the aqueous solution from traveling to the fuel cartridge when the fuel cartridge and the fuel cell are not connected to the water feed tray and further configured to open when the fuel cell and the fuel cartridge are connected to the water feed tray; a spring mechanism operably connected to the water feed tray and configured to eject the fuel cartridge from a water feed connection when the fuel cell is disconnected from the system, or to push the fuel cartridge against the fuel cell providing the force required for a hydrogen seal during operation of the system; a latch locking point configured to receive a latch from the fuel cell and further configured to push the fuel cartridge against the filet cell providing an engagement force for a hydrogen seal between the fuel cartridge and the fuel cell during operation of the system; a water tray needle configured to deliver the aqueous solution to the fuel cartridge; and a bellows assembly configured to hold the aqueous solution. The access door of the water feed tray includes a latching shelf configured to position the access door in a locked open position for receiving the aqueous solution. The latching shelf is further configured to load the spring assembly when the access door is positioned in the locked open position. The access door includes an unlocking mechanism and is configured to unlock and activate the spring assembly to impart a force on the aqueous solution in the water feed tray. The check valve and spring assembly are further configured to provide a controlled flow of aqueous solution to the fuel cartridge. The bellows assembly includes a spring configured inside the bellows assembly. The spring is further configured to pressurize the aqueous solution when the bellows assembly is collapsing or fully collapsed. The fuel cartridge includes: a chemical additive to control reaction conditions in the fuel cartridge; a surfactant to break down surface tension of reaction by-products in the fuel cartridge; a cartridge valve configured to control hydrogen flow from the filet cartridge to the fuel; a needle valve configured to pass aqueous solution from the water tray feed to the fuel cartridge; a reaction feed tube configured to disperse the aqueous solution to the reactant fuel material; a reactant retention screen configured to contain the reactant fuel material in the fuel cartridge; a hydrogen separator membrane configured to filter hydrogen gas produced in the fuel cartridge; a top cap operably connected to a canister body to provide reusable fuel cartridge components; and a roll-over crimp to join a metal canister and a plastic cap. The reaction by-products in the fuel cartridge include sodium silicate. The reaction feed tube includes a T-fitting configured to uniformly disperse the aqueous solution to the reactant fuel material. The fuel cartridge and the water feed tray are further configured to provide a controlled flow of hydrogen to the fuel cell by the configuration of a check valve in the water feed tray, a spring assembly in the water feed tray, and a cartridge valve in the fuel cartridge.