Return Fuel Cells
The Department of Energy recognized the potential of fuel cells for transportation applications and began development of a phosphoric acid fuel cell (PAFC) powered bus in 1987. The transit bus platform was chosen because it offered the most flexibility in packaging the fuel cell and auxiliary component technology available at that time. By 1990, the proton-exchange-membrane (PEM) fuel cell had demonstrated sufficient progress in performance, and thus a light-duty fuel cell vehicle program was launched with General Motors. Methanol was selected as the fuel because of its availability, simplicity of storage, rapid refueling, high energy density, and ability to be easily reformed. In addition, serious consideration has been given to other fuel options, including hydrogen and petroleum. In 1994, DOE initiated programs with two industry teams led by Ford and Pentastar (a Chrysler subsidiary) to develop direct hydrogen-fueled PEM fuel cell propulsion systems. In 1995, a contract was awarded to Arthur D. Little, Inc. to develop a flexible-fuel processor capable of reforming gasoline and other common transportation fuels. Throughout its short history, the DOE program has continued to support exploratory research on critical fuel cell components and materials to address technological barriers to commercialization.
This program is responsive to requirements of the U.S. Energy Policy Act of 1992 (EPACT) which authorizes the development of fuel cell vehicles. It also represents the key fuel cell work being done under the Partnership for a New Generation of Vehicles (PNGV)a U.S. government/industry research and development initiative involving representatives from seven Federal agencies and the Big Three automakers (Chrysler, Ford, General Motors) that began in 1993 to strengthen U.S. competitiveness in the automotive industry. DOE's program specifically addresses the PNGV goal of developing a vehicle to achieve up to three times the fuel efficiency of today's comparable vehicle. Besides the legislative drivers for this program, there is keen international competition in the race to develop PEM power systems for automobilesextensive efforts are underway in North America, Europe and Japan. In 1997, Daimler-Benz of Germany unveiled its third-generation prototype van powered by a Ballard Power Systems PEM fuel cell; and Toyota of Japan unveiled a second-generation prototype fuel cell/battery powered vehicle based on its RAV4 using its own PEM fuel cell technology. Both of these vehicles are fueled by methanol, which is reformed to hydrogen on-board.
The goal of the DOE Fuel Cell Program is to develop highly efficient, low or zero emission automotive fuel cell propulsion systems. Specific objectives include: By the year 2000, validate fuel cell power systems that are (a) 2-3 times more energy efficient than today's comparable vehicles; (b) more than 100 times cleaner than Federal EPA Tier II emissions standards; and (c) capable of operating on hydrogen, methanol, ethanol, natural gas, and gasoline. In addition, by the year 2004, the objective is to validate fuel cell propulsion systems that meet customer expectations in terms of cost (competitive with conventional vehicles) and performance (equivalent range, safety, and reliability as conventional vehicles).
In order for fuel cell propulsion systems to reach their potential, significant technical challenges must be met, including: size and weight reduction, rapid start-up and transient response capability, fuel processing development, manufacturing cost reduction, complete fuel cell system integration, and durability and reliability demonstration. Non-technical barriers to fuel cell vehicle commercialization include capital investment for large-scale fuel cell vehicle production, an alternative fuel infrastructure, consumer awareness, industry standards for mass production and servicing, and the lack of safety regulations.
The program strategy is to work with all stakeholders through the National Fuel Cell Alliance. This government/industry alliance includes domestic automakers, component suppliers, fuel cell developers, national laboratories, universities, and the fuels industry. Pre-competitive fuel cell R&D managed by DOE will attempt to resolve fundamental problems and issues associated with fuel cells and ancillary components that apply to a number of different fuel cell propulsion systems. U.S. automakers have equal access to the technology and products resulting from the pre-competitive R&D. The Fuel Cell Alliance approach has significant benefits for both DOE and America's automakers. By sharing the results of pre-competitive R&D, government and industry will be able to leverage research dollars. By maintaining their own independent vehicle integration team, the automakers will be able to pursue the approaches which they believe provide the greatest payoffs.
With many technical barriers to overcome and a limited budget to work with, the DOE program has been compelled to streamline its scope and focus its resources. In a recent planning workshop, industry and laboratory experts reviewed the program and developed a recommended list of the R&D priorities and a preliminary fuel strategy for fuel cells in transportation. Fuel processing, fuel cell stack components (such as membranes, catalysts, and bipolar plates), and system components (such as heat exchangers, compressor/expanders) are areas where focussed R&D is needed. DOE will contract directly with fuel cell suppliers and component developers, thus allowing all automakers access to the improvements being made among the suppliers.
- High Efficiency, Direct-Hydrogen Fuel Cell System for Automobiles
- World's First Gasoline-to-Fuel Cell Power Demonstration
- Fuel Cell Propulsion System Development
- Fuel Processing and Storage R&D
- Component R&D
The U.S. Department of Energy (DOE) partnered with Ford Motor Company to develop full functional, zero-emission fuel-cell power-system technology for automotive applications. The purpose of this work was to demonstrate the technology in a complete laboratory propulsion system. This fuel-cell system, which operates on direct hydrogen, should achieve weights and volumes competitive with those of internal-combustion-engine propulsion systems. It should also have the potential to meet competitive production costs.
In a major automotive research breakthrough under the Partnership for a New Generation of Vehicles, a fuel cell using gasoline as the fuel has been demonstrated for automotive use, leading the way for high-mileage, fuel-flexible, low-emission electric vehicles that can be conveniently refueled at existing gas stations.
General Motors (GM) completed a three-year effort in 1993, which demonstrated proof-of-feasibility for methanol-fueled, proton-exchange-membrane (PEM) fuel cells as an electrochemical engine for transportation applications. In Phase I, stand-alone operation of a 10-kW PEM fuel cell system was achieved using real-world automotive components such as fluid injectors and pressure regulators. The GM program is currently completing Phase II, which will result in the demonstration of a 30-kW system. Advancements are being made in three areas: fuel processing, fuel cell stack, and system integration. The General Motors development team includes the General Motors Research and Development Center as prime contractor and several participating divisions of Delphi Automotive Systems, namely, Delphi Energy and Engine Management Systems (formerly AC Rochester), Delphi Harrison, Delphi Packard, and Delco Electronics. Key subcontractors include DuPont and Ballard Power Systems.
Ford's Phase I competition among five fuel cell developers is completed. The developers were International Fuel Cells (IFC), Energy Partners, H Power Corporation, Mechanical Technologies Inc (MTI), and Tecogen. The task was to deliver a 10-kW PEM stack for a direct hydrogen system with a performance goal of 3.7 kg/kW within the one-year time frame. Two developers, IFC and MTI were chose to continue in Phase II with the design, fabrication and testing of a 50- kW fuel cell system. Phase II is scheduled to end shortly with the delivery to Ford and then to DOE of two different 50-kW transportation fuel cell systemsthe first of their kind ever built in the U.S. Two conceptual vehicle designs and an extensive hydrogen infrastructure and vehicle safety analysis have been completed. Directed Technologies, Air Products & Chemicals, Praxair Inc., Electrolyser Corporation, and BOC Gases performed the hydrogen-related issues analyses. A new state-of-the-art hydrogen storage tank liner was developed by Lawrence Livermore National Laboratory, EDO Fiber Sciences and Aero Tec Labs. This technology greatly reduces the fuel storage size, which is critical in the vehicle design.
Chrysler/Pentastar's direct hydrogen
fuel cell project is now completed. The fuel cell portion of the effort
was performed by Allied Signal and was focused on a design-to-cost approach
in which materials development plays a critical role. Low-cost bipolar
plates and low-cost membranes have been developed. A 6-kW stack was fabricated
and durability testing of low-cost bipolar plate materials was completed.
Pentastar was supported by Chrysler Liberty, Allied Signal Aerospace, Allied
Signal Automotive, and Allied Signal Research and Technology.
DOE awarded a contract to Arthur D. Little, Inc in 1992 to develop fuel processor systems for reforming methanol, ethanol, natural gas, and other hydrocarbons for use in transportation fuel cell systems, and for development of advanced systems for hydrogen storage on vehicles. This project's objective is to provide fuel flexibility for fuel cell powered vehicles, and to reduce fuel processor size and cost, reduce start-up time, and increase transient response capability. Steam reforming, partial oxidation, and combinations of these processes were investigated. In FY 1994, a 25-kW reformer and a 1-kg hydrogen storage proof-of-concept system were built and tested. In FY 1995, a 40-kW partial oxidation (POX) ethanol fuel processor was built and tested; the State of Illinois co-sponsored this effort. In FY 1996, the development effort culminated in a fuel processor capable of running on gasoline. In FY 1997, this 50-kW fuel-flexible fuel processor was tested on several types of fuel and also integrated with a preferential oxidation (PrOX) system to reduce the carbon monoxide. The main technical challenge is to reduce the carbon monoxide level in the fuel stream, which is a poison to the fuel cell system.
Exploratory research at Los Alamos National Laboratory, Lawrence Berkeley National Laboratory, Brookhaven National Laboratory, and the National Renewable Energy Laboratory is focusing on advanced fuel cell concepts such as direct methanol oxidation in low-temperature fuel cells (DMFCs), improved materials and components for PEM, and electrocatalyst research. Two key objectives are reducing catalyst poisoning and methanol crossover.
Research at Argonne National Laboratory has resulted in a quick-start, lightweight, compact partial oxidation reformer that will be inexpensive to manufacture. In addition to reformer R&D, Argonne is characterizing alloy catalysts for CO tolerance and electrochemical methanol oxidation, developing a dynamic fuel processor and system model, characterizing novel cathode materials for solid oxide fuel cells (SOFC), and modifying a battery test facility to include fuel cell testing capability.
In 1996, six cost-shared contracts were awarded under a program research and development announcement for novel fuel cell stack development (International Fuel Cells, Texas A&M, Energy Partners) and compressor/expander development (Allied Signal, A.D. Little, Vairex). International Fuel Cells is developing a conceptual design of a direct methanol fuel cell stack focusing on methanol impermeable membranes and advanced anode catalysts. Texas A&M University is developing a small-scale PEM stack addressing low platinum and platinum alloy catalyst loading, advanced membranes, internal humidification concepts, lightweight composite materials, and water/thermal management. Energy Partners is developing a small-scale PEM stack focusing on bipolar plate flow optimization, cell stack design studies, and low platinum loading membrane- electrode assembly techniques. A.D. Little, Allied Signal, and Vairex are developing three different prototype compressor/expanders (scroll, turbo, and variable piston, respectively) designed specifically for automotive fuel cell systems.
Reprinted from the Department of Energy Full Page