Storage-stable, fluid dispensing device using a hydrogen gas generator

A storage stable fluid delivery device comprising a liquid chamber containing a liquid to be dispensed, a flexible wall or movable piston positioned between said liquid chamber and a gas chamber into which gas flows from a gas generator structured to produce hydrogen at a substantially constant rate over a period of time such that the fluid flows from the liquid chamber through an outlet as the gas enters the gas chamber, said gas generator containing moisture which participates in the generation of the gas;

• sealing means to prevent substantial permeation of water vapor from the gas generator to the environment during storage;
• and
• wherein the gas generator is an electrochemical gas generating cell comprising a gas-evolving cathode composed of at least a hydrophobic gas permeable layer and a current collector, and an electroactive metal anode wherein said anode is electronically isolated from said cathode by an insulative means which is both ionically and electronically insulative;
• an aqueous electrolyte adapted to be in ionic communication with said anode and cathode;
• wherein said electrolyte is in contact with said electroactive metal anode during storage;
• wherein said gas generating cell contains enough moisture in the electrolyte to sustain water vapor losses due to permeation or leakage during storage, to be consumed in the electrode reactions, to humidify the generated gas, and to remain ionically conductive during the life of the device;
• wherein the anode and cathode are connected through an electric circuit consisting of a means to complete the circuit at the time of activation;
• and a hydrogen permeable moisture barrier means present to permit small amounts of hydrogen generated inadvertently during storage before the electrical circuit means is activated to substantially permeate out of the device and
• said barrier means having sufficiently low water vapor permeation to prevent the escape of substantial water vapor.