Patent ID: 7600541

Claim:
A fuel supply system for a fuel cell system comprising: a supply inlet that provides the fuel in a liquid phase; a vessel coupled to the supply inlet to receive the fuel in the liquid phase; a discharge passage coupled to the vessel to remove gaseous fuel from the vessel and to deliver the gaseous fuel to the supply inlet; a sensor in communication with the discharge passage, the sensor in communication with a control system to interrupt the flow to the supply inlet based on a pressure drop in the discharge passage; a fuel level indicator disposed within the vessel and in communication with the control system that generates a first signal based on a level of fuel in the vessel such that the control system interrupts the flow to the supply inlet based on the first signal; and wherein the sensor transmits a second signal to the control system when the pressure drop in the discharge passage is approximately equal to a pressure associated with the fuel in the liquid phase entering the discharge passage such that the control system interrupts the flow to the supply inlet based on at least one of the first signal and the second signal.