The 2005 Fuel Cell Seminar,

Palm Springs, California, USA, November 14-18, 2005

UTC. A long-time leader and market presence in fuel cells, UTC has a wealth of experience in the DG space with its 200kW phosphoric acid fuel cell (PAFC) with up to 900K BTU/hr of heat for cogeneration applications for commercial stationary. To gauge size, consider that 200kW is enough for about 100 average households. The PAFC uses concentrated HPO4 as an electrolyte which is retained in a silicon carbide matrix. Pt catalysts are used for the anode and cathode. PAFCs operate at >160°C; otherwise the ionic conductivity is poor and CO poisoning of the catalyst results. It runs on natural gas using a reformer. CO2 is not a problem so reformed fuel can be used. Since 1991, 275 systems have been in place with 7,000,000 hours of operation in schools, office buildings, hospitals, and manufacturing. Grid-connected and operating in parallel, they can be grid independent automatically. No pollution, no emissions and a small amount of waste heat (20%) compared to conventional power plant electricity (67%) because heat can be captured for energy generation or heating and cooling and there are no transmission line losses. However, it faces the same capital cost issues as SOFCs coming in at about $3,000-4,000/kW.

Plug Power. A high temperature PEM FC design is being used for Plug Power’s residential heating 4.6 kW electricity, 9kW heat unit for multi-family dwellings. Typically PEM FCs use Nafion and operate well below the 160°C temperature used in this design that uses a PBI (polybenzimidazole polymer) PEM from PEMEAS, Germany. The high temp PEM FC solves a number of problems – the MEA is CO tolerant, it eliminates a gas treatment step in the reformer, no humidification or water management issues, and the design results in 30% fewer parts.

Acumentrics. Working to SECA’s goal of $400/kW, cost reductions are being made by increasing cell power which reduces the number of cells needed, and employing technologies like metal injection molding (MIM) for low cost intricate geometry metal parts. Telecommunications and remote residential will operate on gas and propane with diesel and JP8 for military. Investors include Sumitomo Japan, General Dynamics, Chevron Texaco, and Northeast Utilities.

Integrated co-sintered stack with metal structural support at Argonne National Lab. A way of improving the mechanical properties of durability, shock, and thermal cycling for SOFCs is proposed by co-sintering the brittle electrolyte and anode with metallic gas flow fields and bipolar plate to form an integrated unit for assembling the stack wherein the metallic units serve as the structural members. In addition, they will use ceramic to metal bonds for sealing instead of glass-ceramic.

Flexible Zirconia Electrolyte at Corning. Novel planar technology that is robust for use in 200kW+ SOFCs is based on thin, flexible zirconia electrolyte sheets that can bend to a radius of less than 1cm. This gives them high tolerance for local thermal gradients in electrolyte supported multi cell design (ESM).

Proprietary Cu Anode for SOFC. Franklin Fuel Cells has been working on SOFCs for the last two years that can operate on fuels available today — diesel, gasoline, ethanol propane, as well as, hydrogen in the 3-250kW range. A proprietary copper anode (composite of Cu, CeO2, YSZ) direct oxidation SOFC provides 300mW/cm2 at 800°C on gasoline with no steam or carrier gas, no external reforming. Significant technical problems it must overcome: 1) carbon formation in the fuel distribution system from pyrolysis and 2) prevention of copper sintering which reduces conductivity and decreases anode operation. Typical fuel cells use Ni and YSZ. However, Ni catalyzes the formation of graphite deactivating the cell with carbon deposition. Cu does not.

Fuel Processors

High Sulfur Fuel Processor by Mesoscopic Devices. Fuel cells operating on readily available hydrocarbon fuels are slow to be realized, in part because of the poisoning of the fuel cell and the reformer catalyst by S compounds; the S species must be removed. A regenerable sorbent is desirable for high sulfur fuels for low maintenance, and long runtimes. Mesoscopic has shown a continuous regeneration of the sorbent is an approach that can be efficient and compact for key military fuels like JP-8 and diesel.

Methanol Reforming for Portable and Stationary by Genesis Fuel Tech. Sulfur bearing fuel reforming technology (e.g. diesel, natural gas, propane) has a large number of process steps, control points, catalytic degradation, and poisoning issues. Plus, separate purified water needed for the process must be kept from freezing. Methanol is more straightforward and the water needed can be mixed right in which also avoids freezing problems. The beauty of the Genesis system is that it is as simple as connecting the fuel cells with regulated H2. It can load track without limitations on ramp up and can handle 0-100% transient and can ramp all the way down. Yield is 20l/minute H2 output for the MeOH/water reformer with 99.9999% purity. Weight is 25kg, size 23x53cm.

U.S. Department of Energy’s

Role in Commercialization

DOE Hydrogen Program. DOE is executing a balanced research portfolio for developing fossil, nuclear, and renewable based hydrogen production. Hydrogen from coal will be based on gasification not coal-based electricity. For this carbon capture and sequestration technologies are needed. The nuclear program will rely on heat-based generation of H2. In transportation, DOE has set 2015 as the date for a decision on industry commercialization of FC vehicles. Goals for H2 storage technology are 2.0kWh/kg (6%wt), 1.5kWh/liter.

DOE’s Office of Fossil Energy’s National Energy Technology Labs in Morgantown, West Virginia, and Pittsburgh, Pennsylvania. Its SOFC and fuel cell turbine (FCT) hybrid distributed generation (DG) has three aspects:

SECA, Solid State Energy Conversion Alliance is supporting the development of modular, fuel-flexible SOFCs with a cost target of $400/kW for stationary and APU by 2010.

FutureGen. The goal is for coal-generated electricity and H2 generation by gasification. CO2 will be separated from H2 by novel membranes under development with a captured rate of 90%. Ion conducting metal oxide ceramics in SOFC and ceramic membranes for H2 production are key.

High Temperature Electrochemistry Center, HiTEC, has been established at the Pacific Northwest National Lab (PNNL) with satellite facilities at Montana State University and University of Florida at Gainesville. Solid oxide technology is under study in a number of areas, e.g., electrolyzers, reversible FCs, gas separation membranes, all-ceramic fuel electrode for steam electrolysis.

Portable Fuel Cells

There are many bets on the portable device market as the place for fuel cell technology to make a commercial entrance for a number of reasons. These applications accept a much higher cost per watt-hour than other fuel cell markets, very long runtimes are highly desirable and existing battery technology doesn’t offer a good solution, attributes of small size and light weight are strong drivers in portable products, and the infrastructure for distribution of fuel is not a great problem. In addition, portable military applications echo these same needs to an even more pronounced degree and it can be a source of funds for R&D because the battlefield is transitioning and increasingly becoming more and more electronics-dependent.

Motorola. An MeOH steam reformer coupled with an elevated temperature PEMFC (>120°C) using PBI MEAs (polybenzimidazole doped with strong ox-acids) is being studied because of a list of advantages — higher power density, lower precious metal catalyst loading, low gas permeability, no humidification, simplified water management, (only gas phase water is present), and enhanced kinetics versus low temperature PEMFCs which also have the added difficulty of generating and storing pure hydrogen or DMFC. A 25W system has been demonstrated.

DMFC MTI MicroFuel Cells continues to develop its DMFC running on 100% MeOH with a passive air supply. In an implementation of the FC as a battery extender for an RFID tag reader, the device provides 1 watt of power output to charge an 8Wh Li-ion battery through an upconverter providing an additional 35Wh of extended runtime from the MeOH cartridge. Issues for further development are high precious metal loading and sensitivity to changes in ambient conditions. Dynamics of system operation for load following and slow startup make the hybrid approach necessary.

Green Fuel Cell, Tel Aviv, Israel is addressing the key limitations of cost, energy density, power density, water management and flooding with their pure methanol, nano porous proton conducting membrane, PEM FC. Their PEM cost today is $40/m2 and represents less than 1% of the cost of their 20W accessory power unit for laptop computers which run at 200mW/cm2 and provide 380Wh/l, 290 Wh/kg with a 125ml methanol cartridge. Water is recyled in situ from cathode to anode through the membrane so there is no need for water collection or pumps.

U.S. Army. The Communications-Electronics Research, Development and Engineering Center, CERDEC, at Fort Belvoir, VA has a number of programs for its portable power needs with a range of sizes from 25-250W. And as you might expect, the demands are many and extreme — light weight, rugged, compact, wide environmental ranges in temperature, humidity, high tolerance to dust and sand, rapid start, and silent operation. One project under development is a DMFC by SmartFuel Cell, Germany. One version is a neat methanol for operation at 0-35°C. The other is a dilute methanol for up to 50°C in a desert environment. They show a 400Wh/kg energy density for a 72-hour, 20W mission. Ultracell Inc. is providing a 25W reformed methanol fuel cell for the Land Warrior program. Using hydrogen generation systems of ammonia borane (NH3BH3) General Atomics has a 20W PEMFC and General Dynamics has a unique metal/ceramic PEM FC. In addition, some work on SOFC is being supported. The attraction is the fuel flexibility (e.g., diesel, JP-8) which will support the “One Fuel Forward” policy of the DoD. However, this technology is much less mature and robust at this stage. Adaptive Materials Inc. and NanoDyanmics will provide evaluations of 50-150W portable SOFC using propane. NanoDynamics and Altex Technologies will demonstrate 50W JP-8 fueled SOFC. A 250W field charger that uses JP-8 for 72 hours of operation weighs less than 10kg (no fuel) is being worked on by Idatech and Genesis FuelTech.

In fuel processing, SOFCo EFS Holdings LLC will use its experience in converting heavy hydrocarbon to FC suitable fuels and S removal on converting military fuels. General Dynamics and Aspen Products Group are providing a 5kW with JP-8 reformate with a composition of 24% CO, 22% H2, 51% N2 where S went from 400ppm to 4ppm.

STEP is the Small Tactical Electric Power program for filling the need for emerging man-portable power 500-3000W. Power sources must be light weight, rugged, compact, have a wide temperature and humidity range, be immune to dust and sand, and have rapid start with silent operation.

Portable 75W SOFC-Battery Hybrid by Mesoscopic Devices. The SOFC, typically thought of for multi-kilowatt stationary systems, is getting a lot of attention for portable applications based on achievements in higher power density and compact reformers. So portable SOFCs that may compete with PEM FC and DMFC are being proposed. Mesoscopic Devices for the past three years has been developing SOFCs under 500W. They have demonstrated a 75W generator for military use that is 130x180x250mm, weighs 3kg, runs on propane with an internal hybrid battery for start up and peak power. Half the volume is BOP with the largest parasitic power and noise source being the blower. The FC kicks in after a 45 minute start up. Operation is continuous for several days. Future versions will run on kerosene, jet fuel or JP-8 using a liquid phase desulfurizer.

Portable Hydrogen Generation with NaBH4. Millennium Cell is offering a Hydrogen-on-Demand system which produces H2 by releasing it from NaBH4 in the presence of a proprietary catalyst. The remaining end product of this reaction is NaBO2 which must be discarded. In practice, this is much like disposing of an expended primary battery. From the business side, they are focusing on the military as early adopters with the longer-term market consumer electronics like laptop computers where a 2 -to-3 runtime is sought. As a demonstration, Millennium Cell shows a flat panel passive PEM FC using a Hydrogen-on-Demand fuel cartridge. Another exhibit has it coupled with a Protonex PEM FC for a 30W, 72-hour soldier application where it weighs in at 12 pounds versus 28 pounds for the existing LiSO2 batteries. Field trials for this device will take place throughout 2006.