Danish Power Systems. Progress in HT-PEM fuel cells F-Cell, Stuttgart 30 th Sep Hans Aage Hjuler and Thomas Steenberg

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1 Danish Power Systems Progress in HT-PEM fuel cells F-Cell, Stuttgart 30 th Sep Hans Aage Hjuler and Thomas Steenberg

2 Outline Introduction MEA performance Durability Summary The two Danish test windmills from 1891 and 1897, incl. electrolysis, H 2 storage and H 2 light.

3 About DPS DPS produce and develop the energy efficient HTPEM technology which utilizes renewable fuels. This is to the benefit of our customers, society, public health and the environment DPS is an independent and privately owned company. DPS was founded in Since 2010 DPS has focused on the actual single fuel cell unit (MEA). Strong network with international and Danish companies, universities and organizations. Member of the Danish Partnership for Hydrogen and Fuel Cells. 3

4 High Temperature PEM FC H N H N N N Poly (2,2 -m-(phenylene)-5,5 -bibenzimidazole) n Well-known temperature resistant polymer T g = ~430ºC When doped with phosphoric acid: Proton conductor Wainright and Savinell. J. Electrochem. Soc. 142 (1995) L121 4

5 DPS capabilities - MEA manufacturing Polymer synthesis Membrane casting Electrode spray Assembly and QC 5

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7 Standard Products: Dapozol membranes: o M20 20 my membranes o M40 40 my membranes o M60 60 my membranes o M80 80 my membranes Dapozol MEAs: o G33 3 x 3 cm active area o G55 5 x 5 cm active area o G77 7 x 7 cm active area o G717 7 x 17 cm active area o G x 18 cm active area

8 HT-PEM Technology The HTPEM technology has a number of very attractive features fuel flexibility is a very significant advantages. Typical operating temperature: C. It can work with hydrogen but also reformat (from e.g. natural gas, methanol and LPG). Features: Reformate or H 2 High CO tolerance No need for humidification High value of excess heat => System simplicity 8

9 Simple HTPEM system Reformer Fuel cell Nat. Gas, Methanol Electricity Heat H 2 CO 2 H 2 CO 2 CO CO clean-up to 0,001 % Humidification of the air Air in Air out 9

10 Polarization - hydrogen and reformate Polarization curve for MEAs tested with hydrogen and reformate (2.3% CO) at 160 C. 10

11 HT-PEM MEA technology: Performance Pt loading Membrane (T, DL) Temperature Pt loading MEA design Durability Cost Pt loading MEA design 11

12 MEA losses: 12 Contact resistance Anode resistance + η Cathode losses + η ORR Membrane resistance

13 MEA performance: Reference MEA performance using JM catalyst: 165 cm 2 MEA 160 C CD = 200 ma/cm 2 λ H2 /λ air = 1.5 /

14 E IR-free (mv) MEA characterization RD after 16h Pure O 2 equilibrium potential equilibrium 600 ir free O2 500 ir- free air i (ma/cm²) Performance loss at 1A/cm² due to cathode kinetic loss Performance loss at 1A/cm² due to cathode mass transport loss

15 MEA performance analysis: 1.5 mg Pt/cm 2 on cathode 25 cm 2 MEA 15

16 16 MEA performance analysis:

17 Temperature dependence: 17

18 MEA performance analysis PTFE binder: 0.9 mg Pt/cm 2 on cathode 25 cm 2 MEA 18

19 MEA performance analysis PTFE binder: After 90 h break-in at 200 ma/cm 2 19

20 MEA performance analysis PTFE vs. PBI: PTFE: Potential better kinetics but still some mass transport issues => A potential path to reduced Pt loading. 20

21 MEA - Catalyst comparison : 25 cm 2 MEA 160 C λ H2 /λ air = 1.5 / 2.5 Different carbon substrates! 21

22 Best performance yet: Polarization curves at 160 C 49 cm 2 MEA. The Pt loading on the cathode 1.5 mg Pt/cm 2 The MEA s was measured by Aalborg University. 22

23 Durability testing (on-going): 160 C 240 ma/cm 2 9 cm 2 active area λ H2 = 7 λ air = 12 ΔV = 9 μv/h (avg) 23

24 DPS technology status: PBI synthesis (uniform Mw) PBI membranes (standard and x-linked membranes) MEA s (standard and custom sizes) Performance and durability Commercial production Further up-scaling 24

25 25 Collaboration!

26 Summary & perspectives: HTPEM has a large potential in a number of applications due to system simplicity and fuel flexibility Performance and durability test shows that operating conditions are important for fuel cell performance and life time MEA performance has been significantly improved Scale-up of MEA production is in progress 26

27 Acknowledgements EUDP, the Danish Ministry of Energy Energinet.dk, the Danish Electrical Utilities Danish Agency for Science, Technology and Innovation Danish National Advanced Technology Foundation DTU Energy Conversion, Technical University of Denmark 27

28 28 Our team

29 Thank you for your attention