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Emory S. De CastroE-TEK division, De Nora N.A., Inc.
May 2005
DOE Hydrogen and FC Program Review“Integrated Manufacturing for Advanced MEAs”
Topics 1.A.1, 1.A.2 and 1.A.3 June ’04 through May ’05
DE-FC04-02AL67606
This presentation does not contain any proprietary or confidential information
DE NORA NORTH AMERICA, Inc.GRUPPO DE NORA
Durantes Vincunt
1FC2 De Nora - Du Pont - Nuvera
FC2
OverviewTimeline• Project start: 1 Oct ’01
(2 Jan 02)• Project end: 30 June ’06• Hi T membrane extended Oct 05• Percent complete ~75%
DOE Technical BarriersO. Stack Material and Manufacturing Cost P. DurabilityQ. Electrode PerformanceR. Thermal and Water Management
DOE Technical Targets(consistent with FreedomCar)
• PM loading 2005: 0.6g/ rated kW• PM Loading 2010: 0.2g/rated kW• >2000 hrs life (2005)• >5000 hrs life (2010)• Target achieved using method
amenable to Mass manufacture: <$125/kWe 2005; <$45/kWe 2010
• High Temperature Membrane– All of the above and– Contributes significantly to
achieving System efficiency targets
Budget• Total project
funding:$19.5M– DOE : $14.5M– Contractors: $5M
• Funding FY04:$2.73M• Funding for FY05:$4.64M
DOE Review May 2005 2FC2 De Nora - Du Pont - Nuvera
DOE Review May 2005 3FC2 De Nora - Du Pont - Nuvera
Objectives
1A1: catalyst and structures• New cathode alloys
1A2: Hi T Membrane• Operates sub-ambient to 120 °C
and 25% to 100% RH• Memb. resistance ≤ 0.1 ohm cm2
• Hydrolytic, oxidative, mechanical stability in FC at 120 °C
• No leachable components• H2 fuel permeation ≤ than 5 mA/cm2
• Cost ≤ Nafion®
and ELAT structures that allow an overall cell performance of greater or equal to 0.4A/cm2 at 0.8V or 0.1A/cm2 at 0.85V operating on hydrogen/air with precious metal loadings of 0.3mg/cm2 or less and scales to mass manufacturing technology.
• Support 1A2 with high temp interface and/or GDL structure.
1A3: MEA Fab for Stack Scale• Take advances from 1A1 and/or
1A2 and integrate into pilot manufacturing
• Demonstrate stack scale elements operating with performance consistent with objectives of 1A1 or 1A2
2004/2005 Objectives• 1A1: cited performance at 0.4mg/cm2
using fg-ELAT: transfer to machine fabrication: continue to lower PM, develop high temp interface for A2 materials
• 1A2: single cell testing of HT membrane, evaluate properties at <0oC, begin scale up of advanced membranes
• 1A3: scale-up of 1A1 components; testing at stack scale
DOE Review May 2005 4FC2 De Nora - Du Pont - Nuvera
Team Members responsible for objectives of low precious metal MEAs:
NFCDeliverable: testing of short stacksContaining reference and low PM
MEAs as well as operational protocols
E-TEK (De Nora)Deliverable: Low PM MEAs (5 layer) for short stacks
Containing sub-builds, full builds, as well as reference materials
NEU (Prof. Mukergee)Deliverable: durability profile and
failure mechanism of low PM load MEAs (IBAD and ink based)
CWRU (Prof. Zawodzinski)Deliverable: porosity and
hydrophobicity targets to guide fabrication of low PM MEAs through
modeling of fg-ELAT
Spire BiomedicalDeliverable: coating services for ulra-low loaded
MEAs (IBAD) including batch and roll processingCWRU=Case Western Reserve UniversityNEU=Northeastern UniversityIBAD=Ion Beam Assisted Deposition
DOE Review May 2005 5FC2 De Nora - Du Pont - Nuvera
Approach: Catalyst and Fine Gradient ELAT®• Catalyst: create structure-function relationships supported by Reitveld analysis of
XRD patterns; develop/optimize new prep methods for catalysts and alloys: now in scale-up and durability phase
• GDL/GDE: Develop a new ELAT gas diffusion layer and/or electrode structure based on fine gradients of hydrophobicity and porosity using developmental coating machine– Current focus on machine implementation, and extending approach w
machine– Methodology for fine gradient approach:
Ink preparation parameters
Web properties
Coating parametersGDL/GDE Structure
FC Performance & characterization
Carbon typeParticle sizeAdditives Rheology
Paper and ClothMachine settings
Flow poreGurley No.ConductivityHydrophobicity meas.
Scale to stack
DOE Review May 2005 6FC2 De Nora - Du Pont - Nuvera
Catalyst Activities: Durability and scale up
Impact of alloy structure and H2O2 production (Rotating Ring Disk Electrode to detect H2O2 formation)
Peroxide Yield Comparison Pt Etek 30% vs Pt Cr in Sulfuric Acid
E (V) vs RHE
0.2 0.4 0.6 0.8 1.0
x H
2O2
0.00
0.02
0.04
0.06
0.08
0.10
E (V) RHE 900 vs x H2O2 Pt Etek 30% Col 4 vs x H2O2 PtCr HT 001 Col 7 vs x H2O2 PtCr HT 004
≅ 5.6%
≅ 1.8%
Having established good activity in 2004, now focused on stability
Have scaled alloy to 1Kg, final qualification goal is 3Kg
DOE Review May 2005 7FC2 De Nora - Du Pont - Nuvera
Tools to help build the fine gradient: Method to measure Hydrophobicity -Contact angle and solid surface energy being developed at CWRU
Cobb Titration at E-TEK division
Sample thetaH2Ogammas gammas
d gammasp
30% PTFE, carbon 1 89 ± 3 21 ± 2 13 ± 1 8 ± 2
70% PTFE,carbon 1 101 ± 3 17 ± 1 13.8 ± 0.8 3.1 ± 0.8
30% PTFE,carbon 2 88 ± 7 22 ± 4 14 ± 2 8 ± 3
70% PTFE,carbon 2 96 ± 7 19 ± 3 14 ± 2 4 ± 2
• CWRU uses Washburn method with hexane (wetting) and water to measure internal contact angle and surface energy
Krüss Processor TensiometerElectronic Balance
Test Liquid
Screw Motor
GDL
Sample Holder
Internal Contact Angle to Water theta H2O, GDL Surface Energy gamma s, and its Dispersive and Polar Components gamma sd and gamma sp
COBB TEST: Simple GDL, no gradient
0
0 . 1
0 . 2
0 . 3
0 . 4
0 . 5
0 . 6
2 0 3 0 4 0 5 0 6 0 7 0 8 0% ETHANOL
WT
GA
IN, g
/100
cm2
70% PTFE, Carbon 2
60% PTFE, Carbon 2
55% PTFE, Carbon 2
Team verified earlier Cobb results with tensiometerHowever, previous Cobb method
unable to discriminate a delta of <10% PTFEModified the solvent: can measure
<5% delta PTFEPlan to extend method to gdl
durability tests
“Cobb Titration”
DOE Review May 2005 8FC2 De Nora - Du Pont - Nuvera
Comparison of alloy fg ELAT intermediate build Somerset lab cell vs. Nuvera 225 cm2
1.5BarA (150kPa) air/H2, 70 Deg C
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0.0 0.2 0.4 0.6 0.8 1.0 1.2
Somerset Lab Cell Test, alloy fg ELATintermediate build, 0.40 mg/cm2 Pt
Cambridge Nuvera 225 cm2 Cell Stack, alloyfg-ELAT intermediate build 0.63 mg/cm2 Pt
Volts
Current, A/cm2
Stack scale fg-ELAT constructed by machine and hand steps: supper-scaling at under 0.6A/cm2
Fine gradient ELAT
fg-ELAT, all machine1) fg-ELAT MEA DOE T and P, 1mg/cm2 PM2) fg-ELAT MEA 70 deg C, 1mg/cm2 PM3) Commercial MEA 70 deg C, 1mg/cm2 PMfg-ELAT MEA at DOE T and P with
0.39mg/cm2 PM (0.28mg Pt cat. alloy, 0.11mg Pt anode) results in 0.86V at 0.1A/cm2 and 0.8V at 0.4A/cm2 – interim goal achieved
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0.0 0.5 1.0 1.5 2.0
Current Density / A/cm2
Pote
ntia
l / V
(2) fg-ELAT 1mg/cm2 70C 150kPa
(1) fg-ELAT 1mg/cm2 80C,250kPa
(3) Commercial Benchmark 1mg/cm2 70C 150kPa
DOE Review May 2005 9FC2 De Nora - Du Pont - Nuvera
Summary of “paper” progress to date: started base build
Cathode/Anode: air/H2 150kPa(1.5 Bar A), 70OC; Cell: 70OC, Lynntech CCM
0.4
0.5
0.6
0.7
0.8
0.9
1.00.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6
Current Density / A/cm2
Pote
ntia
l / V commercial standard
CCM and paper GDL
base build for fg ELAT gdllynntech CCM
Commercial paper GDLlynntech CCM
All “standard” 3rd party electrode (CCM) structuresAll PM loadings are high (~1mg/cm2 total PM)Very encouraging performance for fg sub buildAccomplished through extensive changes in formulation and
coating variables compared to carbon cloth woven web
DOE Review May 2005 10FC2 De Nora - Du Pont - Nuvera
High Temperature Interface with Membrane (V) Du Pont
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
Current Density (Amp/cm2)
Cel
l Vol
tage
(V) R.H.=40%
R.H.=30%
R.H.=25%Dry
Uncertainty on R.H. ± 3%
Standard Gradient/machine madeFocused effort on formulation and fabrication
variables (hand fab interface, machine GDE)Demonstrated >1500 hrs with membrane V
under accelerated aging protocol (2003/2004)EXCEEDS POWER GOAL AT 30% RH
Experimental conditions:MEA:
A) Total (cathode and anode) PM = 1 mg/cm2
B) Electrode: HT140E-WC) Ionomer Interface: ProprietaryD) Membrane: DuPont Membrane V
Cell:A) R.H. = 25% to 40%B) Gases: Air (Cathode) and H2 (Anode)C) Cell Temperature: 120 oCD) Total Pressure: 2.0 AtmNOTE:
The R.H. was measured at the cathodic and anodic gas inlets usinga digital relative humidity sensor (Tech-Edge, Inc.).
DOE Review May 2005 11FC2 De Nora - Du Pont - Nuvera
Dual Ion Beam Assisted Deposition
Breakthrough in approach: can make 3d structures with ion beam. Improvement in mass transport
(~0.14 mg/cm2 total Pt below)
Structural Changes vis IBAD @ DOE STD
0.000
0.200
0.400
0.600
0.800
1.000
1.200
0.000 0.200 0.400 0.600 0.800 1.000 1.200
Current Density (Amp/cm 2)
Cel
l Vol
tage
(V)
StructureA IBAD 750
StructureB IBAD 750
StructureC IBAD 750
StructureD IBAD 750
StructureE IBAD 750
StructureF IBAD 750
0.50099.1LT140-E ELAT Reference
0.14279.6IBAD1500 Structure A
0.07170.9IBAD750 Structure A
0.10234.6IBAD STD 750
0.07823.8IBAD550
0.03426.3IBAD250
Loadings(mg/cm2)
Real Surface Area
(cm2/cm2)Sample
Electrochemical Surface Area Measured with fully flooded GDEs, H2 wave, and cyclic voltammetry
Pt Skin-effect catalysts with IBAD
• Use IBAD to create multi-layer structures such as depositing Co, Cr, Ni, or Ag first, and then covering with a thin layer of Pt (which then contacts the membrane)
• Can also use new beam-created structures on the multi-layered catalysts• According to XRD, these are not alloys• Preliminary stability acceptable: will continue detailed durability at NEU• Pt:Co “Pattern A” total PM is 110 ug/cm2
• Standard gradient ELAT® employed as substrate
0
0.2
0.4
0.6
0.8
1
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
Current Density (A/cm2)
Cel
l Vol
tage
(V)
Pt-CoPt-Co Pattern APt-CrPt-Cr Pattern AIBAD550 Std.
Naf
ion
112
Mem
bran
e
Gue
st M
etal
(Co,
Cr,
Ag
or N
i;)H
ost M
etal
(Pt;)
Hos
t Met
al (P
t;)
LT14
00
LT14
00+ -
DOE standard conditions (80oC, 250kPa) H2/air
DOE Review May 2005 12FC2 De Nora - Du Pont - Nuvera
DOE Review May 2005 13FC2 De Nora - Du Pont - Nuvera
Comparison of “IBAD”, best fg-ELAT, and start-of-program benchmark: total PM/ power vs. V in“GM” format
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 0.2 0.4 0.6 0.8 1 1.2Current Density/ A/cm2
Cell
Volta
ge,V
Historical Comparison of IBAD results, at DOE Standard Conditions
gPt/kW at 80oC, 250kAa total (2.5BarA), H2/Air
Pt IBAD deposition on anode and cathode Air H2 250kPa total (2.5BarA), 80oC Nafion 112
Significant gains in performance realized through new cathode structures created by ion beam. Showing capability for higher currents as well.
Total Pt loadingELAT benchmark: 1mg/cm2
fg-ELAT: 0.39mg/cm2
IBAD/ELAT: 0.17mg/cm2
“improved over initial”Merit Review May 0480ug/cm2
FreedomCarJuly 04100ug/cm2
Q4,’04 Review170ug/cm2
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
0.3 0.4 0.5 0.6 0.7 0.8 0.9
ELAT, benchmark
fg-ELAT 05
IBAD 2005
2005 Goal
2010 Goal
Volts
g/kW
DOE Review May 2005 14FC2 De Nora - Du Pont - Nuvera
Responses to Reviewers • Improvements should be benchmarked against commercially available
components, not necessarily internal or start of program benchmarks– Have shown some examples within this presentation, although obtaining
commercial benchmark data at different operating conditions can be difficult– We have also approached third parties to provide comparative data for these
new components versus commercial benchmarks. The effort is on-going.• IBAD approach may be limited in these assemblies’ capability to achieve
high current – especially beyond the quarter power goal of this program– The recent breakthrough has allowed a substantial improvement in higher
current operation: however, we now need to “reinvent” the GDL to respond to this unique interface for improved water management
• Efforts on the fabrication of electrodes for the high temperature membranes of Du Pont should be increased
– 2003/2004 saw limited quantities of samples: however, improvements by the DuPont team in solving materials issues in making membranes has provided more material for 2004/2005. We expect some of the understanding learned from making an interface/electrode for Membrane V may be applicable to the other new materials being developed by Du Pont. Electrode assembly with new membrane materials is a key focus for 2005/2006, as well as scaling Membrane V assemblies to stack scale.
DOE Review May 2005 15FC2 De Nora - Du Pont - Nuvera
Accomplishments/Progress• The team continued to increase power and reduce PM loading
– Met interim goal of 0.8V at 0.4A/cm2 and greater than 0.85V 0.1A/cm2 at DOE test conditions with under 0.4 mg Pt/cm2 total using coating technology suitable for mass manufacturing
• Implementation of fg-ELAT approach on non-woven materials begun: outstanding results with baseline structures may provide a path to achieving final power/PM goals
• Strategy for introducing designed structures for IBAD based fabrications continues to show improvements in power and mass transport at higher currents while approaching 2010 PM loading targets: new approach is subject to a patent application. Realized catalytic activity with layered metal structures
• Have shown first generation high temperature interface capable of approaching DOE power goal with Du Pont’s modified membrane (“Membrane V”)
• Developed much-needed methods to quantitatively measure hydrophobicity for GDL materials. Although initially used to design fine gradient ELAT, these methods will have utility in durability studies
• Began baseline 1,000 hr constant current durability operation
DOE Review May 2005 16FC2 De Nora - Du Pont - Nuvera
Next Steps• Reduce PM loading to 0.3mg/cm2 and scale results to stack level
– optimize fg-ELAT approach through structure refinement and machine practices
– develop fg-ELAT on non-woven web– Use next generation CWRU/CAPI modeling to guide structure design
• Catalyst– Scale up prep for improved alloys: 3Kg target– Continue ex-situ lifetime tests; post-mortem MEA/catalyst analysis
• Ultra-low PM loading (IBAD)– Develop new GDL structures tailored to the unique IBAD “Pt-layered”
interface to realize full catalytic potential of these new materials– Lifetime/durability analysis of IBAD structures (at NEU)– Transition to continuous coating
• Durability– Develop durability protocol and methods at stack level (NFC)
• Refine to incorporate at single cell scale at E-TEK– Using new hydrophobicity measurements, analyze fine gradient sub builds
under forced aging regimes for change in hydrophobicity– Durability testing of machine made fine gradient ELAT MEAs
DOE Review May 2005 17FC2 De Nora - Du Pont - Nuvera
Program 1A2: High Temperature Membrane General Approach
Evaluate small molecule electrolytes
Start
End
Synthesize monomers e.g. H, M, Y Synthesize monomers AE, Z Class
Synthesize Polymers
Evaluate Conductivity
Evaluate Thermal Stability & Swelling
Fabricate membranes
HT FC Testing e.g. Nafion® and inorganic composites
Program officially ended Oct 2004: however encouraging advances in new classes of polyelectrolytes justified an extension of one year for DuPont’s activities. Programs for the other team members were accordingly.
Team Members responsible for objectives of high temperature MEAs:
NFCDeliverable: testing of short stacks
Containing reference and high temperatureMEAs as well as operation protocol
E-TEK (De Nora)Deliverable: High T MEAs (5 layer) for short stacks Containing high temperature interface as well as
reference materials
DOE Review May 2005 18FC2 De Nora - Du Pont - Nuvera
Du PontDeliverable: at least two types of high temperature membranes
Enough of one for stack level testing
CWRU (Prof. Litt)Deliverable: High T membrane Structures
and synthesis for materials fulfilling “ uncollapsible hydrophilic domains”
CWRU (Prof. Zawodzinski)Deliverable: porosity and
hydrophobicity targets to guide fabrication of high temp interface
NEU (Prof. Mukergee)Deliverable: 1. durability profile
of “ultra low” PM load MEAs (IBAD) at Hi T
2. durability profile of High Temp Interface
CWRU=Case Western Reserve UniversityNEU=Northeastern UniversityIBAD=Ion Beam Assisted Deposition
DOE Review May 2005 19FC2 De Nora - Du Pont - Nuvera
1A2 High Temperature Membrane
Past year focused on 3 technology options:
Polymer Type Features
Candidate V Per-fluorinated composite membrane
FC lifetime at 120 C increased vs Nafion®; similar conductivity
Candidate BA Partially fluorinated composite membrane
Increased conductivity vs Nafion®
AE - type
AE: perfluorinatedDesign & synthesis of
partially fluorinated polymers
AE: Best conductivity (73 mS/cm 25%RH), thermal & chem. stability. Challenge to insolubilize & strengthen
DOE Review May 2005 20FC2 De Nora - Du Pont - Nuvera
High Temperature Membrane: Focus areas for 04/05
Conductiveat Low RHAF, AK,
BB, AY, AX
Thermally StablePBI, Teflon®
Polyelectrolyte InsolubleReasonable Swelling Mechanical Strength
Y, AZ
AO
AE
Nafion®,V, BG
BA
Additional dimensions:Chem. & oxid. stabilityLow-T conductivity (new)H2 permeationCostFC durability….
?
04/05 Focus
DOE Review May 2005 21FC2 De Nora - Du Pont - Nuvera
Candidate V
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0 500 1000Time (hr)
Cur
rent
(A/c
m2)
0.750
0.770
0.790
0.810
0.830
0.850
0.870
0.890
0.910
0.930
0.950Life Test Candidate V 40um
OC
V (V
olts
)
Clean clogged filter on humidifier
70% RH
25% RH
F5570
OCV
120 oC H2/air 21 psig 25 cm2 active areaConst. flow = stoic 2/2 anode/cath. @ 1.2 A/cm2
Triple cycle: 1) 10 min OCV 70/70 %RH 2) 5hr 0.5V 70/70 %RH3) 5hr 0.5V 25/25 %RH
• Properties similar to Nafion®:– Conductivity, strength, swelling, H2
permeation• Properties superior to Nafion®:
– Fenton test chemical stability– Lifetime in FC
• Life tests at 120 oC show cycling feeds to lower RH accelerates membrane degradation.– New protocol cycling to 25% RH– More aggressive than pervious
cycling to 40% RH– 1000 hr life test Candidate V
• Membrane scaled-up to size for 250 cm2 short stack; Delivered 17 membranes to De Nora
• Future V work: Increase strength & decrease swelling
DOE Review May 2005 22FC2 De Nora - Du Pont - Nuvera
Progress BA Membrane
Isothermal TGA 150 oC air + 0.5% RH
87
89
91
93
95
0 500 1000time (min)
wei
ght (
%)
BA 14X reduced impurity
Nafion(R) N112
BA 200X reduced impurity
-0.0079 %/hr
-0.0070 %/hr
• Thermal stability of BA membrane significantly improved
• Thermal decomposition dominated by weak-link impurity– ‘04 Focus: Identify impurity,
decrease impurity
• BA membrane with weak links decreased to 1/200 of original– Thermal stability similar to
Nafion®
DOE Review May 2005 23FC2 De Nora - Du Pont - Nuvera
Low-RH Conductivity
Condutivity @ 120 oC 25%RH
05
101520253035404550
0.8 1.0 1.2 1.4 1.6 1.8 2.0IEC (meq/g)
Con
duct
ivity
(mS/
cm)
Nafion N117BA
• Conductivities– BA membranes with high IEC– Up to 45 mS/cm @ 120 0C, 25%
RH– Can still be boiled in water
• Mechanical properties– Poor for IEC above 1.7 meq/g in
current BA membranes• IEC in the range of 1.3 to 1.6
meq/g– 2X to 2.5X conductivity of Nafion®– Maintains mechanical properties– Swelling 62% water uptake
• @1.6 IEC• 100 0C water → 22 0C vacuum
DOE Review May 2005 24FC2 De Nora - Du Pont - Nuvera
Low-Temperature Conductivity
-2.6-2.4-2.2-2.0-1.8-1.6-1.4-1.2-1.0-0.8-0.6-0.4
-45 -35 -25 -15 -5 5 15 25Temperature (deg. C)
log(
Con
duct
ivity
S/c
m)
Nafion® NRE212 temp downNafion® NRE212 temp upBA 1.7 IEC temp downBA 1.7 IEC temp up
• New measurement method gives low hysterisis between 0 oC and -40 oC– 4-point probe of initially-wet
membrane cooled/heated in cryo GC
• BA membrane maintains significant advantage over Nafion® only to -20 oC
• At -40 oC, both membranes have similar conductivity
• Due to BA having many of the membrane properties, and good relative conductivity over a wide range of temperatures, the High Temperature Membrane Program was extended
DOE Review May 2005 25FC2 De Nora - Du Pont - Nuvera
FC Performance BA vs N112
0.40
0.45
0.50
0.55
0.60
0.65
0.70
0.75
0.80
0.85
0.90
0.95
0.00 0.25 0.50 0.75 1.00 1.25
Current Density (A/cm2)
Cel
l Vol
tage
(V)
N112 70%RHN112 25%RHBA 70%RHBA 25%RH
F5491F5658
120 oC H2/air 250 kPa25 cm2 GDE• BA membrane
– 53 µm thick– Similar to Nafion® N112
thickness• Superior performance to N112
at low RH.– Even though electrodes are still
PFSA• Future work on BA
– Deliver samples to De Nora– Reduce wrinkles & swelling– Increase FC durability– Will ultimately need also
electrodes based on BA or other adv. electrolyte to deliver MEA performance
AE Type• Immobilization strategy identified for AE-type polymer• New monomers and partially fluorinated copolymer
synthesized - Candidate BL– Succeed in obtaining high MW and tough membrane
• Mw 124,000, IV 3.5– Membrane is insoluble in room-temp water, soluble in hot water
• Partially success on immobilization (make insoluble)• Melting of polymer, Tm 126 oC (76 J/g), needs to be raised
– Monomer chemistry compromised stability & conductivity• Thermal stability, Tonset 228 oC (too low to be practical)• Conductivity 360 mS/cm @95%RH 80C, only 0.2 mS/cm @25%RH
• Future AE work: Strategies identified to increase thermal stability, melting point, and conductivity– Monomer syntheses begun
DOE Review May 2005 26FC2 De Nora - Du Pont - Nuvera
DOE Review May 2005 27FC2 De Nora - Du Pont - Nuvera
AcknowledgementsNortheastern University• Prof. Sanjeev Mukerjee• Robert J. Allen (E-TEK) Distinguished
Visiting Scientist• Andrea F. Gullá (E-TEK), Ph.D.• Basker Veeraraghavan, Ph.D.
(Postdoctoral Fellow) • Madhusudan Saha, Ph.D.
(Postdoctoral fellow)• Vivek Srinivasamurthi (Ph.D.
candidate)• Kartikeyan Ramamoorthi (Ph.D.
candidate)
De Nora N.A. E-TEK div
• Yu-Min Tsou, Ph.D.• Lixin Cao, Ph.D.• Hua Deng, MS, ChE• Chien Hou• Michael Schneider• Maria Cayetano• Jeffrey Morse• Laura Bellamy
DuPont• Mark Roelofs, Ph.D
(Project Leader)• R. Dan Lousenberg, Ph.D.• Mark Teasley, Ph.D.• Zhen-yu Yang, Ph.D.• Rosa Ruiz-Alsop, Ph.D.• John J. Borowski• Robin Blackburn• David Lilly• Charles Wheeler
Case Western Reserve U.• Prof. Morton Litt• Casey Check (Graduate
Student)
Spire BiomedicalNadar Kalkhoran, Ph.D.Jason Burns
DE NORA NORTH AMERICA, Inc.GRUPPO DE NORA
Durantes Vincunt
CWRU/CAPITom Zawodzinski, Ph.D.Vladimir Gurau, Ph.D.
NFCOlga PolevayaStack Testing Team
DOE Review May 2005 28FC2 De Nora - Du Pont - Nuvera
Publications and PresentationsBy CWRU• M. Bluemle, V. Gurau, J. A. Mann, T. A. Zawodzinski Jr., E. S. De Castro, Y. M. Tsou: “Characterization of
Transport Properties In Gas Diffusion Layers for PEMFCs”, 206th Meeting of Electrochem. Soc., Honolulu, Ha, October 2-8, 2004
• M. Bluemle, V. Gurau, J. A. Mann, T. A. Zawodzinski Jr., E. S. De Castro, Y. M. Tsou: “Permeability and Wettability Measurements for Gas Diffusion Layers for PEM Fuel Cells”, 2004 Fuel Cell Seminar. San Antonio, TX, November 1-5, 2004
By E-TEK• Hua Deng, Qingzhi Guo; Maria Cayetano; Yu-Min Tsou; Emory Sayre De Castro, "An Investigation of Ionic
Conductivity of the PEMFC by AC Impedance Spectroscopy", Meeting of Electrochem. Soc., Honolulu, Ha, October 2-8, 2004
• Yu-Min Tsou, Lixin Cao, Emory De Castro “High Performance Oxygen Reduction Catalyst For PEM and DMFC Fuel Cells”Meeting of Electrochem. Soc., San Antonio, Tx May, 2004
• Emory S. De Castro, Yu-Min Tsou, Lixin Cao and Chien Hou “Approaches for low cost components and MEAs for PEFCs: current and future directions”, Fuel Cell Seminar, San Antonio, Nov, 2004
• Emory S. De Castro, “New Nano-Catalysts and Reduction of Component Costs for Portable Fuel Cells”, Small Fuel Cells, Arlington, Va., April 2004
By NEU• 'High Performance Electrode with very Low Pt Loading Prepared by Dual Ion Beam Assisted
Deposition in PEM Fuel Cells' M. S. Saha, S. Mukerjee, A. F. Gulla and R. J. Allen' Extended Abstracts for the Meeting of the Electrochemical Society to be held in Quebec, Canada, May 2005.
• 'Dual Ion Beam Assisted Deposition as a Method to Obtain Low Loading-High Performance Electrodes for Proton Exchange Membrane Fuel Cells', A. F. Gulla, M. S. Saha, R. J. Allen and S. Mukerjee, Electrochemical and Solid State Letters, (Submitted)
• 'Oxygen Reduction and Transport Characteristics at a Platinum and Alternative Proton Conducting Membrane Interface' L. Zhang, C. Ma and S. Mukerjee, J. Electroanalytical Chemistry 58, 273 (2004).
DOE Review May 2005 29FC2 De Nora - Du Pont - Nuvera
Hydrogen Safety
The most significant hydrogen hazard associated with this project is: Testing single cells or short stacks at higher temperature with novel membrane materials
pinholes/cross over at the higher temperatures may lead to more catastrophic consequences
Hydrogen Safety• Our approach to deal with this hazard is:
– Stations in ventilated enclosures with 3 levels of hydrogen detection & interlocks.
H2 Detector“Open Space”
around test station
plumbing
All fuel cell hardware contained within ventilated enclosure
DOE Review May 2005 30FC2 De Nora - Du Pont - Nuvera
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