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Small Fuel Cells 2004
Arlington, Virginia
May 6-7, 2004
David Edlund
IdaTech, LLC
Bend, OR
This annual conference (in its sixth year) is
organized and hosted by the Knowledge Foundation.
This year the two-day main conference focused
on small fuel cells for portable power applications
while the one-day pre-conference seminar covered
combinatorial methods and research for discovering
new catalysts for fuel cell applications. The
conference was held at the Doubletree Hotel Crystal
City in Arlington, Virginia, conveniently located
near Reagan National Airport and the Pentagon
City metro station. Serge Pan, conference
organizer, expects to keep this location for next
year’s meeting.
Application of Combinatorial
and High-Throughput Methods
for Fuel Cell Development
The pre-conference seminar comprised eight papers
from industry and academia describing approaches
and results of catalyst discovery work using combinatorial
methods. If you are not familiar with this field
of study, think of it as a very sophisticated
trial-and-error approach using tiny, sometimes
minute, samples. Once initial samples that exhibit
interesting catalytic properties are discovered,
then the work begins of analyzing the material
to determine exactly what the composition of interest
is. This is easier said than done: it involves
chemical as well as physical characterization
since structure may be the unique attribute that
gives rise to catalytic activity.
Eugene Smotkin (NuVant Systems and faculty
positions at both Illinois Institute of Technology
and University of Puerto Rico at Rio Piedras)
explained the importance of sample preparation
in the discovery of electrocatalysts, focusing
on Pt-Ru compositions. Indeed, the catalytic activity
of the sample may be strongly dependent on sample
preparation methods. Smotkin also illustrated
with several examples that one cannot simply assume
a uniform alloy is derived from mixing metal precursors
and then processing them to give the electrocatalyst.
Phase separation does occur and often the final
catalyst is a complex mixture of different alloy
phases, including the pure metal starting materials.
Jay Witacre (Jet Propulsion Laboratory)
described sputtering methods to achieve a compositional
gradient of two or more different materials, and
Levi Thompson (University of Michigan)
described high-temperature synthetic routes to
make metal carbides and nitrides. But one of the
more unique approaches was presented by Paolina
Atanassova (Cabot Superior MicroPowders) using
a spray-pyrolysis technique. This is a simple
process in which solutions containing metal salts
and suspended metal-oxide or carbon powder (support)
are sprayed into a heated reactor. The temperature,
atmosphere, and residence time are varied to achieve
different chemical reactions, resulting in a wide
range of potential products. This technique is
perhaps unique in that the process readily scales
from 100 milligrams to 1000 kilograms.
Once samples are prepared by any method, they
must be screened for activity. Again, we heard
reports on many different approaches. Symyx is
perhaps the most advanced in this regard with
their high-throughput screening technology and
extensive library of compounds and activity. Peter
Strasser described how Symyx conducts a first-phase
screening by preparing literally hundreds or thousands
of new materials by gradient-based physical vapor
depositions. These samples are prepared as an
array (8 by 8) on a wafer, each sample is connected
to electrical leads and then activity for the
relevant half reaction can be measured to give
an indication of relative performance. The best
samples are then advanced to the second phase
wherein the material is synthesized by conventional
techniques at a larger scale and again tested.
This is often an iterative step as the fabrication
method may not yield material with activity shown
by the original sample (see above comments).
Eduardo Wolf (University of Notre Dame) described
a clever and fast approach to identify relative
activity of water-gas-shift (WGS) catalysts. Since
the WGS reaction is exothermic, Wolf’s group
places small samples of new materials on a wafer
and then subjects them to a mixture of CO and
water vapor. Using thermography, relative reactivity
is displayed as hot spots, the more reactive materials
presumably being hotter than those with less activity.
Amit Nayar (Illinois Institute of Technology)
uses a laser to heat specific samples on a wafer
and then looks for reaction products by mass spectroscopy.
In this way he can place many small catalyst samples
in a common “reactor” at one time.
Small Fuel Cells for Portable
Power Applications
The two-day main conference focused on small
fuel cells for portable power applications and
was attended by an estimated 160 persons from
at least eight countries in Europe, Asia, and
North America. Twenty-three oral presentations
were given; there was also a poster session, company/organization
exhibitions, and a panel session.
The technical papers were split between DMFC and
PEMFC (using hydrogen). There were also a few
papers discussing methods for making hydrogen
to use in these PEMFCs (IdaTech, Motorola, Millennium
Cell, and Mesofuel). Overall, there was a high
degree of anticipation for new products to be
coming soon, and Walter Nasdeo (Ardour
Capital Partners, LLC) pointed out that there
is growing optimism in the financial communities
concerning energy-technology companies. Nasdeo
said that funding (both private and public) is
available to companies with products being sold
at a positive margin.
Perhaps the best example of product commercialization
in this space was reported by Manfred Stefener
(SFC Smart Fuel Cell AG). Stefener reported that
Smart Fuel Cell has sold “several hundred”
fuel cell products to industrial and private customers.
On July 1 of this year, Manfred reported that
Smart Fuel Cell will launch the model 850 which
is a 50W version of their current model 825 (25W
DMFC). Methanol crossover and concentration management
are “solved problems,” and pure methanol
is purchased by the customer in a range of canisters
sized from 2.5 liters to 10 liters. Smart Fuel
Cell is targeting remote monitoring (security)
applications, portable highway traffic signs,
and recreational (boat, RV, remote cabin) markets.
Jerry Hallmark (Motorola) presented their
development work targeting a small (about 10W)
reformed hydrogen fuel cell system. The Motorola
approach is to use a micro-reformer, made from
inexpensive ceramic tapes, coupled to a high-temperature
PEMFC (acid-doped PBI). The primary fuel to be
reformed is methanol mixed with water. Millennium
Cell showed results from their small sodium borohydride
reactors and plans to offer this as a small cartridge
for consumer devices. IdaTech discussed a different
approach to fuel reforming that is more versatile
and yet still produces >99.95% pure hydrogen
from any fuel. A new compact planar reactor incorporating
patented hydrogen purification was shown (this
targeting the 50W to 1kW space). A 200W prototype
weighs in at about 0.5kg and exhibits cold startup
times of a few minutes.
Paul Osenar (Protonex) showed a family
of compact and lightweight PEMFC stacks sized
from about 20W up to about 250W. Protonex has
focused on part-count reduction and adaptation
of high-volume manufacturing methods to PEMFC
stack design and construction. Their goal is to
drive cost reduction while maintaining acceptable
performance over the range of 10W to 1kW.
At fuel cell conferences it is somewhat unusual
to hear about the balance-of-plant (BoP) components.
Fortunately, the organizers invited a paper from
Mesoscopic Devices, one of the leading developers
of small BoP components. Christine Martin
described some of the work directed at reducing
size, mass, and power consumption of BoP pumps
(liquid and air). She also showed an example of
total system integration that Mesoscopic Devices
completed for a DMFC system. Air delivery is typically
a large consumer of power, and these devices are
often heavy. Martin showed an example where Mesoscopic
Devices developed a small air blower that will
deliver 2 liters/minute of air at 0.3 psi: it
draws 0.6W, produces 45dB, and weighs 22 grams.
In comparison, another supplier offering a blower
with similar output specs has inferior performance
specifications (1.5W, 48dB, and weighs 56 grams).
Shimshon Gottesfeld (MTI Microfuel Cells)
presented an update on activities at MTI surrounding
DMFC system development. It was clear that MTI
has focused much effort on simplifying the over
system and BoP, apparently successfully although
details could not be revealed for reasons related
to pending patent applications. Like Smart Fuel
Cell, MTI also has learned to design a DMFC system
so that the user may supply 100% neat methanol,
rather than a dilute methanol-water mixture. Water
is recovered from the fuel cell and mixed in the
proper ratio with the neat methanol. This is done
automatically and is transparent to the user.
Gottesfeld reported that the first commercial
product from MTI will be a “device-integrated
DMFC/battery power system for Intermec’s
RFID tag reader.”
Several interesting papers were presented by various
groups regarding truly micro fuel cells including
Art Homa (Neah Power Systems), Levi
Thompson (University of Michigan), Didier
Marsacq (National Atomic Agency of France),
Christopher Hebling (Fraunhofer Institute
for Solar Energy Systems), and Kevin Stanley
(National Research Council of Canada – Institute
for Fuel Cell Innovation). These devices are made
on silicon wafers using microelectronics manufacturing
methods. Power levels are <1W and scale-up
is unclear. In general, these micro-fuel cells
seem to be intended to replace batteries in portable
electronics. This work is still developmental,
and commercial products in the near term are not
expected.
Overall, this was a very informative fuel cell
conference, and it covered a wide range of topics
(especially if the pre-conference seminar is considered).
Those interested in more information, perhaps
even purchasing the conference proceedings, should
contact the Knowledge Foundation at (617) 232-7400
or www.knowledge press.com.
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