The invention provides a fuel cell system, including a fuel cell having an anode chamber and a cathode chamber, wherein the anode chamber is in fluid communication with a hydrogen reservoir, and wherein the cathode chamber has an inlet and an outlet. The cathode chamber comprises non-intersecting flow channels, and the non-intersecting flow channels provide fluid communication between the cathode inlet and outlet. The fuel cell has a first connection to an electrical load, wherein the first connection comprises a first diode adapted to prevent current flow to the fuel cell. A blower is in fluid communication with the cathode inlet. The blower has an electronic connection to a controller, and the blower is adapted to vary a flow of oxygen through the cathode chamber according to a control signal received from the controller. The system includes a battery having a second connection to the electrical load, the second connection being in parallel with the first connection of the fuel cell to the load, and the second connection comprising a second diode adapted to prevent current flow to the battery. The controller maintains the flow of oxygen such that an output power capacity of the fuel cell is limited by the amount of oxygen flowed through the fuel cell.