Direct methanol fuel cells (DMFCs) are attractive for various applications, above all, however, as replacements for batteries or accumulators. They may be used in different power classes. A market analysis indicated that the use of a DMFC energy system in the kW class had the best chance of commercial realization if applied in forklift trucks for material handling in large distribution centers or warehouses. An advantage of such energy systems is that there is no need for the relatively time-consuming recharging of the lead-acid batteries, nor is it necessary to have spare batteries available for multishift operation. This calls for DMFC energy systems that are capable of replacing the existing Pb accumulators in terms of space requirements and energy. However, this requires considerable improvements to be made in terms of power and stability over time of DMFC systems and, in comparison to their present status, an increase of overall efficiency. Recent cost analyses for the overall system; for example, show that for the DMFC stack, a durability of at least 5000 h must be achieved with an overall efficiency for the DMFC system of at least 30%, with the constraint that the system can be operated in a water-autonomous manner up to an ambient temperature of 35 °C. As part of a joint R&D project with industrial partners, two systems were constructed and each subjected to long-term testing for 3000 and more than 8000 h, respectively, with realistic load profiles from driving cycles. In this test, the stack from the first system, DMFC V 3.3–1, displayed an aging rate of approximately 52 μV h−1 at a current density of 100 mA cm−2. This corresponds to a performance degradation of 25% over a period of 3,000 h. The DMFC V 3.3–2 system, a modified and optimized version of the first system, also underwent long-term testing. In this case, the aging rate of the stack was only approximately 9 μV h−1 at a current density of 100 mA cm−2. The system has thus been operated to date for more than 8000 h under realistic load profiles.

References

1.
Dohle
,
H.
,
Mergel
,
J.
, and
Stolten
,
D.
, 2002, “
Heat and Power Management of a Direct-Methanol-Fuel-Cell (DMFC) System
,”
J. Power Sources
,
111
(
2
), pp.
268
282
.
2.
Noelke
,
M.
, 2007, “
Development of a Direct Methanol Fuel Cell System for the Power Segment below 5 kW
,” Ph.D. thesis, Schriften Forschungszentrum Jülich, Reihe Energietech./Energy Technol, Jülich, Germany.
3.
Mergel
,
J.
,
Glüsen
,
A.
, and
Wannek
,
C.
, 2010, “
Current Status of and Recent Developments in Direct Liquid Fuel Cells
,”
Hydrogen and Fuel Cells, Fundamentals, Technologies and Applications
,
D.
Stolten
, ed.,
Wiley, Weinheim
,
Germany
, pp.
41
60
.
4.
Rashidi
,
R.
,
Dincer
,
I.
,
Naterer
,
G. F.
, and
Berg
,
P.
, 2009, “
Performance Evaluation of Direct Methanol Fuel Cells for Portable Applications
,”
J. Power Sources
,
187
(
2
), pp.
509
516
.
5.
Ren
,
X.
,
Zelenay
,
P.
,
Thomas
,
S.
,
Davey
,
J.
, and
Gottesfeld
,
S.
, 2000, “
Recent Advances in Direct Methanol Fuel Cells at Los Alamos National Laboratory
,”
J. Power Sources
,
86
(
1–2
), pp.
111
116
.
6.
Mergel
,
J.
,
Müller
,
M.
,
Janßen
,
H.
, and
Stolten
,
D.
, 2008, “
Direktmethanol-Brennstoffzelelnsysteme - Eine Option Für Flurförderfahrzeuge,” Forschungszentrum Jülich GmbH, Jülich
, Technical Report No. 1866–1793.
7.
SFC, 2011, “
Pressemitteilung vom 18.01.2011: SFC Energy AG verkauft 20.000 EFOY-Brennstoffzelle
,” http://www.investor-sfc.de/de/pm.php?type=pm&id=224&year=2011&lang=de.
8.
MTI, 2011, “
MTI Micro begins Fuel Cell Product Field Testing with DOE and Nyserda Funding
,” http://www.mtimicrofuelcells.com/technology/breakthrough.asp.
9.
Toshiba, 2009, “
Toshiba Launches Direct Methanol Fuel Cell in Japan as External Power Source for Mobile Electronic Devices”
, News Release 22 Oct. 2009, http://www.toshiba.co.jp/about/press/2009_10/pr2201.htm.
10.
Butler
,
J.
, 2009, “
Portable Fuel Cell Survey 2009
,” http://www.fuelcelltoday.com/media/pdf/surveys/2009-portable-free.pdf.
11.
Arico
,
A. S.
,
Baglio
,
V.
, and
Antonucci
,
V.
, 2009, “
Direct Methanol Fuel Cells: History, Status and Perspectives
,”
Electrocatalysis of Direct Methanol Fuel Cells
,
H.
Liu
and
J.
Zhang
, eds.,
Wiley-VCH, Weinheim
,
Germany
, pp.
1
78
.
12.
Janßen
,
H.
,
Blum
,
L.
,
Kimiaie
,
N.
,
Maintz
,
A.
,
Mergel
,
J.
,
Müller
,
M.
,
and
Stolten
,
D.
, 2005, “
Performance Characterization of a 4-Wheel Scooter
,”
3rd European PEFC Forum
,
Lucerne
,
Switzerland
.
13.
Jungheinrich
,
A. G.
, 2006, “
ECE 220 Horizontal Order Picker 2000 kg
,”
Datasheet
, http://www.jungheinrich.de/fileadmin/general/juprod/pdf/de_ECE_225_.pdf
14.
Elgowainy
,
A.
,
Gaines
,
L.
, and
Wang
,
M.
, 2009, “
Fuel-Cycle Analysis of Early Market Applications of Fuel Cells: Forklift Propulsion Systems and Distributed Power Generation
,”
Int. J. Hydrogen Energy
,
34
, pp.
3557
3570
.
15.
Management Engineers, 2007, “
Feasibility Study Direct Methanol Fuel Cells
,” IEK-3, Internal Report.
16.
Oorja Protonics Inc., 2011, “
Return on Investment for Oorjapac Operation
,” http://www.oorjaprotonics.com/benefits/ROI.html.
17.
Wilhelm
,
J.
, 2010, “
Hybridisierung Und Regelung Eines Mobilen Direktmethanol-Brennstoffzellen-Systems
,” Ph.D. thesis, RWTH Aachen University, Aachen.
18.
Wilhelm
,
J.
,
Janßen
,
H.
,
Mergel
,
J.
, and
Stolten
,
D.
, 2011, “
Energy Storage Characterization for a Direct Methanol Fuel Cell Hybrid System
,”
J. Power Sources
,
196
(
12
), pp.
5299
5308
.
19.
Wilhelm
,
J.
,
Blum
,
L.
,
Janßen
,
H.
,
Mergel
,
J.
, and
Stolten
,
D.
, 2009, “
Control Strategy for a Direct Methanol Fuel Cell Hybdrid System
,” 3rd
European and International Conference eHydrogenia
,
Bucharest
,
Romania
.
20.
Janßen
,
H.
,
Blum
,
L.
,
Hehemann
,
M.
,
Mergel
,
J.
, and
Stolten
,
D.
, 2010, “
System Technology Aspects for Light Traction Applications of Direct Methanol Fuel Cells
,”
18th World Hydrogen Energy Conference
2010,
D.
Stolten
, eds.,
Forschungszentrum Jülich GmbH
,
Essen
, Book 5, pp.
497
502
.
21.
Gluesen
,
A.
,
Müller
,
M.
,
Kimiaie
,
N.
,
Konradi
,
I.
,
Mergel
,
J.
, and
Stolten
,
D.
, 2010, “
Manufacturing Technologies for Direct Methanol Fuel Cells (DMFCs)
,”
18th World Hydrogen Energy Conference
2010,
D.
Stolten
and
T.
Grube
, eds.,
Forschungszentrum Jülich GmbH
,
Essen, Germany
, Book 1, pp.
219
226
.
22.
Müller
,
M.
,
Janßen
,
H.
,
Wilhelm
,
J.
,
Mergel
,
J.
, and
Stolten
,
D.
, 2008, “
Direct Methanol Fuel Cell Systems—An Option for Fork-Lift Trucks
,”
17th World Hydrogen Energy Conference
,
Brisbane
,
Australia
.
23.
Cabello-Moreno
,
N.
,
Crabb
,
E.
,
Fisher
,
J.
,
Russell
,
A.
, and
Thompsett
,
D.
, 2009, “
Improving the Stability of PTRU Catalysts for DMFC
,”
ECS Meeting Abstracts
,
902
(
10
), pp.
983
.
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