Abstract: A polymer adhesive includes a mixture of polyurethane and polyacrylate polymers, which lead to a miscible hybrid polymer system that displays a single glass transition temperature (Tg). A laminate includes a first substrate, a second substrate, and the polymer adhesive between the first substrate and the second substrate.

Abstract: A power converter has a digital control that interfaces with an analog driver through a simple and efficient signal connection. A single signal may be used to encode frequency and pulse width information to realize a number of control functions based on the digital control algorithms. The functions of analog and digital circuitry are separated to improve flexibility in the power converter, and the interface signal provides a digital-to-analog interface for communicating control information rapidly and efficiently. The arrangement permits realization of a volt-second clamp among other programmable features that were previously set through hard wiring with passive components.

Abstract: A temperature control system and method for a fuel cell stack cooling system is disclosed. The temperature control system includes a coolant circulation line for circulating a coolant to and from a fuel cell stack. A coolant pump is provided in the coolant circulation line, and a pump ?P sensor is provided in fluid communication with the coolant circulation line on inlet and outlet sides of the coolant pump. The pump ?P sensor measures a change in pump pressure between the inlet and outlet sides of the coolant pump. A pump map is provided having correlated values of pump speed, change in pump pressure and coolant flow rate for correlating the coolant flow rate with the pump speed and the change in pump pressure to attain a desired coolant flow rate for optimum fuel stack cooling.

Abstract: The present invention is a method of operating a fuel cell stack and system that minimizes the potential for having a large pressure differential between the anode and cathode flow fields and a low relative humidity occurrence within the cathode flow fields. This is accomplished by tempering the downward transient in power demand seen by the fuel cell stack. The downward transient in power demand on the fuel cell stack is tempered by reducing the rate at which the power generated by the fuel cell stack is decreased and providing the excess power generated by the fuel cell stack to other parasitic components of the fuel cell system.