Water activated instant hydrogen generator with passive control on hydrogen demand

A wearable power unit, comprising:

• a fuel cell;
• a belt attached to the fuel cell;
• and
• a hydrogen gas generating apparatus coupled to the fuel cell, comprising:
• a first chamber comprising a first surface coupled to a plurality of sidewalls, a rigid porous member disposed opposite the first surface and coupled to the plurality of sidewalls, a first filter coupled to the rigid porous member, and a first volume defined by the first surface, the plurality of sidewalls and the rigid porous member;
• a first mixture comprising a chemical hydride and a catalyst disposed within the first volume of the first chamber;
• an outlet fluidly coupled to the first chamber;
• a second chamber comprising a first surface coupled to a plurality of sidewalls, wherein the outlet is coupled to the first surface, a second volume defined by the first surface and the plurality of sidewalls, wherein the first chamber is coupled within the second volume, and a second filter disposed between the outlet and the first chamber;
• a connector;
• a third chamber comprising a third volume defined by a first surface and a plurality of sidewalls, wherein the third chamber is coupled by the connector to the second chamber, and wherein the third chamber is fluidly coupled to the first chamber, and wherein the third chamber is configured to hold water;
• a sealing element coupled to at least one of the second chamber or the third chamber;
• and
• a resilient member coupled to the first surface of the third volume of the third chamber and configured to control the flow of water into the first chamber via movement of the resilient member in response to hydrogen gas pressure within the apparatus.