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ISO TC 197 Meetings Held in Japan
by Karen Hall
Vice President, Technical Operations of the
National Hydrogen Association
The ISO TC 197 annual plenary meeting and a series of Working
Group Meetings were held in Japan in conjunction with the
15th World Hydrogen Energy Conference.
 Working
Group 12: Hydrogen fuel — Product Specification met at
the Engineering Advancement Association of Japan (ENAA) office
in Tokyo on June 24 & 25. (Photo: View of the waterfront
overlooking Queen's Square Yokohama)
The Working Group (ISO TC 197 WG 12) walked through the
proposed amendment to ISO 14687, based on data developed
by the Japanese Automobile research Institute (JARI). The
data represents an excellent start at beginning to quantify
the effects of impurities on PEM fuel cells that many automotive
manufacturers plan to use in fuel cell vehicles.
The data, however, is limited to short-term testing and
analyses only some specific impurities on two types of fuel
cell membranes.
The WG discussed concerns with moving toward an amendment to
the ISO standard at this time. Concerns included the following:
- Once an International Standard is published, it takes
time to implement any required changes. Should any critical
new information come to light requiring an amendment, the
time to complete the process could be significant.
- The data does an excellent job at characterizing the effects
of certain contaminants to certain fuel cell membranes for
short-cycle testing. The group voiced significant interest
in testing effects of additional contaminants as well as
performing long-term testing to fully characterize the point
at which the contaminants in question cause irreversible
catalyst poisoning. It may also be desirable to test additional
materials.
- The proposal specifications for some contaminants, including
Sulfur, were beyond the lower limits of detectability, using
conventional gas chromatography. This presents difficulties
for all parties. Hydrogen suppliers can not certify the
fuel has met the specified values, as these levels can not
be detected. Providing fuel certified only to the values
that can be detected results in irreversible poisoning to
the fuel cell. This issue is based on a “factor of
500” applied to the concentration obtained from testing.
This is done to accommodate the fact that a 99.8% fuel utilization
is desired. That means that when the last 0.2% of fuel is
left, the contaminants therein could be 500 times more concentrated
than in the original supply (1/0.002 = 500). This assumption
could also be explored with additional testing.
The group felt that while the work presented by JARI was
an excellent start, it may be premature to make an amendment
to the standard before the additional testing could be completed.
It was also suggested that testing could be performed by several
countries, so that more ISO TC 197 members could collaborate
on the data being developed.
 There
appears to be interest in doing a number of things to resolve
these issues. JARI would like to see something available quickly
for near-term demonstration projects only. It may be that the
current activity is re-scoped for this purpose. There is also
significant interest in pulling together available data for
broader application. A New Work Item Proposal (NWIP) may be
proposed in the near future for a Technical Report to collate
existing data for use internationally. Countries could then
contribute to the growing knowledge of effects of various impurities
for hydrogen fuel cells. (Photo: Hydrogen and hybrid vehicles
on display at the 15th WHEC)
There may also be interest in work to develop data for stationary
fuel cell applications. The current effort is focused solely
on PEM fuel cells for automotive applications.
The Working Group would like to engage more participation
from Europe. They will try to schedule a meeting in the
Fall, possibly in Europe.
The U.S. will continue to engage a wider range of stakeholders
to determine a U.S. position the broader issues associated with
hydrogen fuel quality.
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