NOVELTY - Regulating hydrogen flow from vessel (10), involves applying electrical potential between first (210) and second electrodes (220) of electrochemical cell (40). The first electrode has a higher electrical potential with respect to zero than the second electrode. Electrical current is flowed through the cell. The electrical potential is modulated to control an outlet pressure of the hydrogen evolved at the second electrode, or an amount of electrical current flowed through the cell is modulated to control outlet flow of hydrogen evolved at the second electrode.    USE - For regulating hydrogen flow from vessel.    ADVANTAGE - The cell can provide a hydrogen output at a pressure higher than the tank, eliminating the need for storing hydrogen at high pressure. A relatively low pressure hydrogen tank can be used.    DETAILED DESCRIPTION - Regulating hydrogen flow from vessel, involves applying electrical potential between first and second electrodes of electrochemical cell. The first electrode has a higher electrical potential with respect to zero than the second electrode, and is in fluid communication with a hydrogen source gas in the vessel. Electrical current is flowed through the cell as hydrogen is ionized at the first electrode and evolved at the second electrode. The electrical potential is modulated to control an outlet pressure of the hydrogen evolved at the second electrode; or an amount of electrical current flowed through the cell is modulated to control an outlet flow of the hydrogen evolved at the second electrode. An INDEPENDENT CLAIM is included for an integrated electrochemical hydrogen separation system, comprising a vessel containing hydrogen gas; an electrochemical cell comprising a proton exchange; a power supply (50); and a valve (150, 160) in fluid communication with second electrode. A controller (30) energizes the electrochemical cell to cause hydrogen to be pumped from the first electrode to the second electrode, and/or measures an amount of hydrogen flowed through the electrochemical cell and a pressure of the vessel.    DESCRIPTION OF DRAWING(S) - The figure is a schematic diagram showing an integrated electrochemical hydrogen separation system.    Vessel (10)    Controller (30)    Electrochemical cell (40)    Power supply (50)    Valve (150, 160)    First (210)    Second electrodes (220)