Upload
others
View
4
Download
0
Embed Size (px)
Citation preview
Improving Lifetime Performance of SOFC for Truck APUs
(Förbättringar av livslängden av fastoxidbränsleceller-APUför tunga fordons applikationer)
Claudia Göbel, Jan Froitzheim and Jan-Erik SvenssonEnergy and Materials
Chemistry and Chemical EngineeringChalmers University of Technology
United States
Claudia Göbel
Outline
Part I: Overview SOFC for Mobile Applications
Part II: Final results from the FFI project
3
The electrolyte is an oxygen ion conducting material (600-900 ºC)
Advantages• High electrical efficiency
• O2- conductive electrolyte Fuel flexibility (H2, natural gas,
biogas.. diesel)• High operating temperature
No need for expensive catalysts such as Pt
4
Solid Oxide Fuel Cell (SOFC)
Electrolyte CathodeAir side
AnodeFuel side
e-e-
Oxygen Ions
Oxygen ions
Electrolyte supported Anode supported
>800 °C 800-650 °C
Metal supported
700-500 °C
There is a general trend towards lower operating temperatures.
⇒ Possibility to use less expensive materials⇒ Higher efficiency possible⇒ Longer lifetimes⇒ Faster heating/cooling
5
Solid Oxide Fuel Cell (SOFC)
SOFC for Mobile Applications
• APU units for trucks (eg. Delphi; EU-projects: DESTA, SAFARI, SAPIENS; National projects: Mestrex (AT), FFI project (SE))
• Range extenders for EV vehicles (eg. Nissan, Honda; new EU project: COMPASS)
• Special applications such as drones, robots, unmanned water vehicles…etc. (eg. Adelan R&D, NEXceris, US military, NASA)
6
APU units for trucks
www.eberspaecher.com 7
Range extenders for EV vehicles
https://newsroom.nissan-global.com/releases/160614-01-e 8
How the e-Bio Fuel Cell system works• Fueled by liquid fuel: easy to handle, can use conventional fuel tank• Hydrogen generated through reformation of 100% ethanol or ethanol-blended water• Power generated by SOFC stack from reformate hydrogen and air• Generated electricity charges battery and powers drive motor
Nissan collaborates with Ceres, Plansee and AVL for range extenders
[1] http://insideevs.com/nissan-unveils-worlds-first-solid-oxide-fuel-cell-vehicle-e-nv200-sofc/[2] http://media.nissan.eu/content/dam/services/SE/brochure/Nissan_e-NV200_BtoC_SE.pdf 9
• An electric vehicle with a 5 kW SOFC system and a 30 liter tank for bio-ethanol.[1]
• Range: 600 km[1] (compared to ~150 km[2] without the SOFC range extender)
Companies focusing on SOFC for mobile applications
10
UK-based SOFC manufacturer
Austrian-based automotive consulting firm as well as an independent research institute.
Finnish/Estonian-based SOFC manufacturer
Electrolyte supported Anode supported
>800 °C 800-650 °C
Metal supported
700-500 °C
11
Solid Oxide Fuel Cell (SOFC)
AVL List GmbH
V. Lawlor, M. Reissig, J. Makinson, J. Rechberger ECS Transactions. 78 (2017) 191. 12
Mestrex Project:Development of a highly fuel efficient range extender system based on a high-temperature fuel cell (SOFC), which can be operated with CO2-neutral, ethanol-based fuels.
Mestrex Objective: AVL Eventual Target:
System performance (net)
3kW - 5kW 20 kW - 30 kW
Electrical efficiency >50% 55% - 60%
Noise level <60 dB <40 dB
Start time <30min <5 min
Weight/power <20 kg/kW 3-4 kg/kW
Volume/power <25l/kW 4-5l/kW
Lifetime >500h 5000h
Cost/kW <10,000€/kW €250/kW (Funded by the Austrian Ministry for Transport, Innovation and Technology (BMVIT) in the program
“Mobility of the Future”)
Electrolyte supported Anode supported
>800 °C 800-650 °C
Metal supported
700-500 °C
13
Solid Oxide Fuel Cell (SOFC)
Elcogen
http://www.elcogen.com/technology/ 14
Operating temperature
650°C
Operating temperature
650°C
Elcogen stacks have achieved a WORLD
RECORD in primary energy conversion efficiency to
electricity of 74 %
Elcogen
High efficiency, high power density and fuel flexibility offered by Elcogen is prerequisite for automotive industry. Battery electric vehicle range extender
utilizing biofuels discards the plug-in charging need and onboard power production in long haul trucks decreases significantly diesel fuel emissions.
Industrial CHPResidential & mCHP Automotive Electrolyzers for energy storage and power to fuelIndustrial CHP
http://www.elcogen.com/technology/ 15
Automotive
Electrolyte supported Anode supported
>800 °C 800-650 °C
Metal supported
700-500 °C
16
Solid Oxide Fuel Cell (SOFC)
Ceres Power – Metal supported SOFC
R.T. Leah, A. Bone, E. Hammer, A. Selcuk, M. Rahman, A. Clare, S. Mukerjee, M. Selby ECS Transactions. 78 (2017) 87.
17
Ceres Power – Metal supported SOFC
18
[1] http://www.cerespower.com/work-with-our-steelcell/applications-for-our-steelcell/[2] http://www.cerespower.com/news/latest-news/new-joint-development-agreement-with-honda/[3] https://www.businessgreen.com/bg/news/2463114/ceres-power-teams-up-with-nissan-to-develop-range-extending-fuel-cell-for-evshttps://www.businessgreen.com/bg/news/2463114/ceres-power-teams-up-with-nissan-to-develop-range-extending-fuel-cell-for-evs
Ceres Power – Metal supported SOFC
19
[1] http://www.cerespower.com/work-with-our-steelcell/applications-for-our-steelcell/[2] http://www.cerespower.com/news/latest-news/new-joint-development-agreement-with-honda/[3] https://www.businessgreen.com/bg/news/2463114/ceres-power-teams-up-with-nissan-to-develop-range-extending-fuel-cell-for-evshttps://www.businessgreen.com/bg/news/2463114/ceres-power-teams-up-with-nissan-to-develop-range-extending-fuel-cell-for-evs
[2]
[3]
Ceres Power – Metal supported SOFC
R.T. Leah, A. Bone, E. Hammer, A. Selcuk, M. Rahman, A. Clare, S. Mukerjee, M. Selby ECS Transactions. 78 (2017) 87.
20
Only 9 min until operation (15 min to full power)
Ceres Power – Metal supported SOFC
R.T. Leah, A. Bone, E. Hammer, A. Selcuk, M. Rahman, A. Clare, S. Mukerjee, M. Selby ECS Transactions. 78 (2017) 87.
21
Up to 3000 cycles were presented at the conference
Other projects/companies focusing on SOFC for mobile applications
22
• COMPASS (Current EU project H2020): Collaborative effort of AVL, Plansee, Nissan and Research Center Jülich to develop advanced SOFC APU systems for range extender applications in passenger cars.
• SAFARI project: SOFC APU For Auxiliary Road-truck Installations running on LNG (End December 31, 2016).
• SAPIENS: SOFC Auxiliary Power using Liquid petroleum gas (LPG) as fuel (End October 31, 2015).
• Delphi Automotive LLP: Has developed and demonstrated a practical, operational SOFC auxiliary power unit (APU) for heavy duty commercial trucks that operate with many types of fuels including natural gas, diesel, bio-diesel, propane, gasoline, coal-derived fuel and military logistics fuel.
• Eberspächer: APU running on Diesel (Partner in the DESTA project)• Adelan R&D: Projects include unmanned aerial vehicles (UAVs), road
vehicles, recreational vehicles, portable power and micro combined heat and power (mCHP) applications.
Outline
Part I: Overview SOFC for Mobile Applications
Part II: Final results from the FFI project
23
The FFI project
24
Förbättringar av livslängden av fastoxidbränsleceller-APU för tunga fordonsapplikationer
Single cells 1 kW stack 3 kW stack
Our project partner is ElcogenElcogen is a Finnish/Estonian SOFC developer selling cells and stacks
http://www.elcogen.com/technology/ 25
Elcogen
http://www.elcogen.com/technology/ 26
Operating temperature
650°C
“Elcogen’s industry leading SOFC technology is positioned to achieve market-enabling targets in the 3 most critical fuel cell performance parameters: efficiency,
lifetime and cost”
Solid Oxide Fuel Cell (SOFC)
27
Electrolyte CathodeAir side
AnodeFuel side
e-e-
Oxygen Ions
Oxygen ions
U < 1 V
Solid Oxide Fuel Cell Stack
28
e-
O2-
O2-
O2-
O2-
e-
O2-
O2-
InterconnectFerritic Stainless Steel
• Similar thermal expansion as the ceramics used in SOFC
• Good electrical conductivity• Formability• Cheap to produce
Cost analysis 1 kW Stack50 000 Units
30%
35%
16%
19%
Cells InterconnectsSealing, End plate etc Assembly Hardware
Manufacturing cost analysis of 1 kW and 5kW solid oxide fuel cell (SOFC) for auxillary power applications. 2014, Battelle.
29
Improve oxidation resistance at the cathode and the anode side
Reduce chromium evaporation
Reduce electrical resistance
Improving Lifetime and Performance of SOFC for Truck APUs- In a cost efficient way
30
Objectives
Problems at Interconnect levelCorrosion
• Chromium evaporation
• Growing Cr2O3 layer→ Chromium consumption→ Increase in electrical resistance
31
Cr2O3(s) + 2 H2O(g) + 1.5 O2(g) 2 CrO2(OH)2(g)
poisoning thecathode!
O2 +H2O(g)
FeCr FeCrCr2O3
CrO2(OH)2(g)
Possible ways to overcome Cr-evaporation
FeCrMn FeCrMnCr2O3
(Cr,Mn)3O4
FeCrMn
Co (640nm)
Change substrate composition:
CrO2(OH)2 (g)
Apply Co coatings:
Decreases Cr-evaporation, however, still too high!
Minimize Cr evaporation by presence of (Co,Mn)3O4
Cr2O3
(Co,Mn)3O4CrO2(OH)2 (g)
FeCrMn
32
Could the mechanical deformation process cause increased Cr vaporization?
The pre-coated concept
33
SteelCo coating Stamping
Uncoated and undeformed
No signs of increased Cr vaporization after mechanical deformation/stamping!
Crofer 22 APU, 850 ˚C, Air-3% H2O, 6 sL min-1
Co Co
Coated (post-coated and pre-coated)
The pre-coated conceptCr-evaporation
H. Falk-Windisch, M. Sattari, J.-E. Svensson, J. Froitzheim J. Power Sources.297 (2015) 217.
34
0 hPre-coated
336 hPre-coated
Possible ways to decrease oxide scale growth rate
Ce (10nm)Co (640nm)
FeCrMn
Apply Ce coating:
Ce (10nm)
Apply Co coatings:
Minimize Cr evaporation by presence of (Co,Mn)3O4
FeCrMn
FeCrMn
Co (640nm)Cr2O3
(Co,Mn)3O4CrO2(OH)2 (g)
FeCrMn
Decreases oxide scale growth35
Mass gain
36
Co+Ce has lower mass gain than Co
Sanergy HT, 850°C, 6000ml/min
Co+Ce coating performs as good as Co coating with regard to Cr-evaporation
Cr Evaporation1000 hours exposure
37Sanergy HT, 850°C, 6000ml/min
Cr Evaporation
38
Co/Ce coated FSS
Uncoated FSS (1000 h measurement) Average rate: 1.85 * 10-4 mg cm-2 h-1
FSS, 800°C, 6000ml/min air
Area Specific Resistance
39Ce/Co coated FSS, 800°C
Summary
• Co coating greatly decreases Cr-evaporation.
• Self-healing effect of Co allows for pre-coating.
• Ce coating decreases growth of Cr2O3 layer.
• Longterm stability of Ce/Co coating up to 37 000 h with regard to Cr-evaporation and ASR.
• Stack data with Elcogen shows good performance of Ce/Co coating.
40
The FFI project
41
Förbättringar av livslängden av fastoxidbränsleceller-APU för tunga fordonsapplikationer
Kostnadseffektiva IT-SOFC Bränsleceller för mobilaapplikation