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DOE Fuel Cell Program
Hydrocarbon MembraneProject: FC7
Chris J. Cornelius, Cy H. Fujimoto, Michael A. Hickner
Sandia National LaboratoriesChemical and Biological Technologies
P.O. Box 5800Albuquerque, NM 87185
May 16th 2006
This presentation does not contain any proprietary or confidential information
Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company,for the United States Department of Energy under contract DE-AC04-94AL85000.
DOE Fuel Cell Program
OverviewHydrocarbon Membrane
Timeline• Start Date: 3/15/05• End date: 9/30/06•• Project Completion (FY06): Project Completion (FY06): 50%50%
Budget• Total project funding
− DOE share: $300K− Contractor share: $0K
• Funding received in FY05: $150K•• Funding for FY06: Funding for FY06: $150K$150K
Partners• Interactions and Collaborations
Automotive & FC Stack Producer (Independent Testing & DOE Call Partners)Academia (Virginia Tech, CWRU, Clemson, UK - Jun Jin)
Technical BarriersBarriersBarriers: A, B, C, D, F, I
• High Temperature Membranes for Distributed Power Applications
• Advanced Membrane R&D• Membrane Materials,
Components, Processes• Advanced MEA Meeting 2010
Targets• Direct Methanol Fuel Cells• Auxiliary/Portable Power
2
DOE Fuel Cell Program
ObjectivesResearch Program Goals – DOE 2010 Targets
Overall • Membrane Conductivity (0.1, 0.7, & 0.01 S/cm @ Target, RT, -20oC)• Operating Temperature (<= 120oC & 1.5 kPa abs)• Catalyst Loading (0.3 g/kW)• Fuel Cell Performance (400 mA/cm2 and 320 mW/cm2 @ 0.8V)• Membrane cost ($40/m2)• Hydrogen and Oxygen Crossover (2 mA/cm2)• Survivability (-40oC to 120oC)• Durability (5000 hrs @ <= 80oC & 2000 hrs @ >= 80oC)
2006 • Synthesize and Characterize SDAPP physical properties.• Demonstrate SDAPP (Sulfonated Diels-Alder Polyphenylene) PEM fuel
cell performance (1st Generation).• Continue developing structure-property performance PEM and fuel cell
relationships to create improvements in PEM materials.
2007 • Membrane Conductivity and Fuel Cell Performance• Survivability (-40 oC to 120 oC), Degradation, and Durability Studies• Catalyst Loading and Membrane Cost
3
DOE Fuel Cell Program
• Thermal & Chemical Stability(Thermal, Chemical, Processing)
• Low Fuel Cross-Over(Low O2 & H2 - Tunable)
• Gas Transport(Electrode & PEM)
• Low Interfacial Resistance(MEA – Electrodes)
• Chemical Diversity and High MW• Proton Conductivity & Morphology
• Thermal & Chemical Stability(Thermal, Chemical, Processing)
• Low Fuel Cross-Over(Low O2 & H2 - Tunable)
• Gas Transport(Electrode & PEM)
• Low Interfacial Resistance(MEA – Electrodes)
• Chemical Diversity and High MW• Proton Conductivity & Morphology
nSO3H
HO3S
ApproachHydrocarbon Membrane - SDAPP
1st Generation Sulfonated Diels-Alder Polyphenylene (SDAPP)
4
DOE Fuel Cell Program
Fuel Cell PerformanceDevelopment of Non-Nafion MEAs
5
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0 500 1000 1500 2000 2500current density (mA/cm2)
cell
pote
ntia
l (V)
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
HFR
( Ω-c
m2 )
N112 30% NafElect.
SDAPP 30%Naf Elect.
SDAPP 30%SDAPP Elect.
SDAPP 15%SDAPP Elect.
SDAPP 7%SDAPP Elect.
SDAPP4 Membrane 1 mil thick80°C cell temperatureH2 200sccm Air 500 sccm20 psig50% RH gas feeds
DOE Fuel Cell Program
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0 200 400 600 800
Current Density (mA/cm2)
Cel
l Pot
entia
l (V)
29 w t % Nafion 1100 0.2 mg Pt/cm2 on Nafion 112
7 w t % SDAPPe 0.4 mg Pt/cm2 on SDAPP4
16 w t % SDAPPe 0.4 mg Pt/cm2 on Nafion 112
120°C Cell temperatureH2 200sccm Air 500 sccm
20 psig50% RH gas feeds
• Highly sulfonated samples do show good high temperature & low RH fuel cell performance.
• Enhanced performance due in part to our new alternative binders.
Fuel Cell PerformanceDevelopment of Non-Nafion MEAs
6
DOE Fuel Cell Program
Fuel Cell Performance50% RH @ 80 oC and 120 oC
120oC80oC
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0 200 400 600 800 1000Current density (m A/cm 2)
Cel
l pot
entia
l (V)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
HFR
(-c
m2 )
SDAPP 2.2 IEC mem - 30wt % SDAPPf3 elect
Nafion 112 mem - 30 wt % Nafion elect
SDAPP 2.2 IEC mem - 15 wt % SDAPPe elect
0.0
0.7
1.0
0.9
0.8
0.6
0.5
0.3
0.1
0.4
0.2
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0 500 1000 1500 2000
Current density (m A/cm 2)
Cel
l pot
entia
l (V)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
HFR
( ℵ-c
m2 )
Nafion 112 mem - 30 wt% Nafion elect
SDAPP 2.2 IEC mem - 15 wt % SDAPPe elect
SDAPP 2.2 IEC mem - 30wt % SDAPPf3 elect
SDAPP 2.2 IEC mem - 15 wt % SDAPPf3 elect
Cel
l Pot
entia
l (V)
Cel
l Pot
entia
l (V)
Nafion 112 - 30wt% Nafion Elec.SDAPP4 – 15wt% SDAPPe Elec.SDAPP4 – 30wt% SDAPPf3 Elec.SDAPP4 – 15wt% SDAPPf3 Elec.
Nafion 112 - 30wt% Nafion Elec.SDAPP4 – 15wt% SDAPPe Elec.SDAPP4 – 30wt% SDAPPe Elec..
HFR
(ohm
*cm
2 )
HFR
(Ohm
*cm
2 )
0 500 200015001000Current Density (mA/cm2)
0.0
0.7
1.0
0.9
0.8
0.6
0.5
0.3
0.1
0.4
0.2
0 200 1000800400 600Current Density (mA/cm2)
Substituting SDAPPe and SDAPPf within the electrode layers can improve or approach same performance as a Nafion based MEA. However, fuel cell performance is dependent on electrolyte type, loading, and hydrogen fuel cell operating temperature.
7
DOE Fuel Cell Program
Fuel Cell PerformanceO.5V with 30wt% Nafion Electrodes
0
200
400
600
800
1000
1200
1400
1600
1800
50 60 70 80 90 100 110 120 130
Temperature (°C)
Cur
rent
Den
sity
(mA
/cm
2 )
100% RH
75% RH
50% RH
25% RH
Nafion 112 SDAPP4 (2.5mil)
0.4 mg Pt/cm2
high stoic H2/Air flow
8
0
200
400
600
800
1000
1200
1400
1600
1800
50 60 70 80 90 100 110 120 130
Temperature (°C)
Cur
rent
Den
sity
(mA
/cm
2)
100% RH75% RH50% RH25% RH
DOE Fuel Cell Program
0
100
200
300
400
500
600
700
800
900
1000
50 60 70 80 90 100 110 120 130
Temperature (°C)
Cur
rent
Den
sity
(mA
/cm2 )
100% RH
75% RH
50% RH
Fuel Cell PerformanceO.5V with 30wt% Nafion vs non-Nafion Electrodes
Nafion 112 SDAPP4 (2.5mil)
9
0.4 mg Pt/cm2
high stoic H2/Air flow
0
200
400
600
800
1000
1200
1400
1600
1800
50 60 70 80 90 100 110 120 130
Temperature (°C)
Cur
rent
Den
sity
(mA
/cm
2)
100% RH75% RH50% RH25% RH
DOE Fuel Cell Program
SDAPP electrodes provide good porosity and do not significantly impede electrochemistry within the electrode structures.
A v e ra g e T a fe l S lo p e (1 0 -2 0 m A )
O 2 A ir O 2 A irN 1 1 2 N a f io n 3 0 % N a f io n E le c tro d e s -8 7 .5 -8 3 .5 -5 9 .1 -5 1 .2S D A P P 3 0 % S D A P P E le c tro d e s -8 3 .1 -7 9 .3 -6 3 .1 -6 7 .6
5 0 R H 1 0 0 R H
Fuel Cell PerformanceDevelopment of Non-Nafion MEAs
10
Electrons
Reactants & Water
H2O, O2, H2 H2O
H +
e -
Protons
Electrons
Reactants & Water
H2O, O2, H2 H2O
H +H +
e -e -
Protons
DOE Fuel Cell Program
Fuel Cell Performance50%RH Nafion & Non-Nafion Electrodes on N112
11
N112 with 30wt% Nafion Anode and Cathode
N112 with 15wt% SDAPPf Anode and Cathode
N112 with 15wt% SDAPPf Anode and 30wt% Nafion Cathode
N112 with 30wt% SDAPPf Anode and Cathode
80oC & 50%RH
0.0
0.2
0.4
0.6
0.8
1.0
1.2
0 400 800 1200 1600 2000
Current Density (mA/cm2)
Cel
l Pot
entia
l (V)
120oC 50%RH
0.0
0.2
0.4
0.6
0.8
1.0
1.2
0 400 800 1200 1600 2000
Current Density (mA/cm2)
Cel
l Pot
entia
l (V)
DOE Fuel Cell Program
0.00E+00
5.00E-05
1.00E-04
1.50E-04
2.00E-04
2.50E-04
3.00E-04
60 80 100 120 140Temperature (°C)
Hyd
roge
n Pe
rmea
bilit
y (c
m2 /s
)
Nafion 112SDAPP2SDAPP3SDAPP4
Hydrogen CrossoverMEA & PEM Testing
0.00E+00
5.00E-14
1.00E-13
1.50E-13
2.00E-13
2.50E-13
3.00E-13
3.50E-13
0 20 40 60 80 100
Relative Humidity
Gas
Per
mea
biity
mol
e cm
/ kP
.
0
0.5
1
1.5
2
2.5
3
3.5
Rat
io N
112
Per
m/S
andi
a P
erm
Sandia Nafion Ratio
In collaboration/Contract with Giner Electrochemical Systems
Barriers Addressed– O2 and H2 Crossover– Fuel Cell Performance– Thermochemical Stability
Barriers Addressed– O2 and H2 Crossover– Fuel Cell Performance– Thermochemical Stability
12
DOE Fuel Cell Program
Fuel Cell PerformanceIncreasing Durability & Conductivity
In collaboration/Contract with Dr. Deck – Virginia Tech
• Polymerization yielded solid polymer• Incorporation into DA PEM - TBD • Physical Properties - TBD
Barriers Addressed– Conductivity– Fuel Cell Performance– Thermochemical Stability
Barriers Addressed– Conductivity– Fuel Cell Performance– Thermochemical Stability
7
C7F7
FF
30%C7F7
C7F7
C7F7
C7F7
C7F7
O
OC
13
DOE Fuel Cell Program
Fuel Cell PerformanceIncreasing Conductivity – Ullman Reaction
Br Br
O3S
SO3
N
N
HO3S
SO3H
In collaboration/Contract with Dr. Litt - CWRU
• Polymerization yielded solid polymer/ionomer• MW - TBD • IEC & Conductivity – TBD• Physical Properties - TBD
Barriers Addressed– Conductivity– Fuel Cell Performance– Membrane Cost
Barriers Addressed– Conductivity– Fuel Cell Performance– Membrane Cost
14
DOE Fuel Cell Program
Fuel Cell PerformanceImproving PEM Morphology & Function - AFM
In collaboration/Contract with Dr. Perahia - Clemson
Barriers Addressed– Conductivity– Fuel Cell Performance– Membrane Cost & Durability
Barriers Addressed– Conductivity– Fuel Cell Performance– Membrane Cost & Durability
Ion Transport
RandomBlock
Ion Transport
RandomBlock
15
DOE Fuel Cell Program
Enhanced Acidity & Hydration– Acid Groups– Organic-Inorganic Composites
Gas Transport– Tailoring polymers for Electrode and
PEM utilization
Structure-Property-Function– Structured Materials (sulfonation) – Improved Stability (Mechanical
(cycling) and chemical)– Minimize interfacial resistance and
improve adhesion of PEM and catalyst layer
Enhanced Acidity & Hydration– Acid Groups– Organic-Inorganic Composites
Gas Transport– Tailoring polymers for Electrode and
PEM utilization
Structure-Property-Function– Structured Materials (sulfonation) – Improved Stability (Mechanical
(cycling) and chemical)– Minimize interfacial resistance and
improve adhesion of PEM and catalyst layer
Future WorkImproving Fuel Cell Membranes
O2
19
24.5
270n*
Ph Ph
Ph
S
Ph Ph
Ph
F F
F F
*
PhPh
Ph
*
PhPh
Ph
*
5.2n*
Ph Ph
Ph
S
Ph Ph
Ph
*
n
PhPh
Ph
*
PhPh
Ph
*
F F
FF
H2
94
99
H2 and O2 Permeability Units in Barrer10-10cm3/cm2 s cm of Hg (at STP)
16
DOE Fuel Cell Program
SummaryHydrocarbon Membrane
Relevance:Identify and Answer fundamental issues with Nafion and alternative PEM and MEA fuel cell implementation
Approach:Develop a Structure-Property-Performance relationship of alternative PEMs in order to mitigate poor fuel performance relative to DOE targets.
Technical Accomplishments and Progress:Capabilities Established: Material design and synthesis, characterization, device testing, system performance measurements, and predictions
Technology Transfer & Collaborations:Active involvement with industry and academia$50K$50K award award by Lockheed Martin under a Shared Vision to initiate the by Lockheed Martin under a Shared Vision to initiate the understanding of hydrocarbon PEM scaleunderstanding of hydrocarbon PEM scale--up. up.
Proposed Future Research:Continue structure property function improvements to achieve DOE fuel cell goals
17
DOE Fuel Cell Program
Reviewer’s CommentsResponse to Previous Year Review
1.Relevance to overall DOE objectives – (Weight - 20%)• Key technology that must be enhanced.Key technology that must be enhanced.We have taken our first generation membrane and are adding functionalities to improve conductivity, durability, and performance.
2.Approach to performing the R&D – (Weight - 20%)•• Separate MEA interface from bulk PEM propertiesSeparate MEA interface from bulk PEM properties•• Improve Conductivity (low RH) then Electrode InterfaceImprove Conductivity (low RH) then Electrode InterfaceResearch goals separate PEM from MEA interface. New Chemistry initiated during the next fiscal years is expected to address 2010 DOE performance targets.
3.Technical Accomplishments and Progress toward overall project and DOE goals – (Weight - 35%)•• Measure conductivity of new membranes as a function of T and RMeasure conductivity of new membranes as a function of T and RH in order to H in order to separate PEM versus MEA advances.separate PEM versus MEA advances.Research goals separate PEM from MEA interface. New Chemistry initiated during the next fiscal years is expected to address 2010 DOE performance targets.
18
DOE Fuel Cell Program
Reviewer’s CommentsResponse to Previous Year Review
4.Technology Transfer / Collaborations with industry / universities / other laboratories – (Weight - 10%)•• Need to develop industrial contactsNeed to develop industrial contacts•• Develop collaboration on MEA durability and electrode integratDevelop collaboration on MEA durability and electrode integrationionWe have taken our first generation membrane and are adding functionalities to improve conductivity, durability, and performance.
5.Proposed Future Research approach and relevance –(Weight - 15%)•• Need more aggressive challengesNeed more aggressive challenges•• Too Broad Too Broad –– optimize PEM then electrodeoptimize PEM then electrodeResearch goals separate PEM from MEA interface. New Chemistry initiated during the next fiscal years is expected to address 2010 DOE performance targets of performance, durability, and cost).
19
DOE Fuel Cell Program
Publications and PresentationsMarch 2005 - Present
PublicationsHickner, Michael A.; Fujimoto, Cy H.; Cornelius, Christopher J. “Transport in
sulfonated poly(phenylene)s: Proton conductivity, permeability, and the state of water” Polymer (accepted April 18th, 2006).
Fujimoto, Cy H.; Hickner, Michael A.; Cornelius, Christopher J.; Loy, Douglas A. “Ionomeric Poly(phenylene) Prepared by Diels-Alder Polymerization: Synthesis and Physical Properties of a Novel Polyelectrolyte” Macromolecules(2005), 38(12), 5010-5016.
PresentationsFall 2006: FuelCell 2000 (2), ECS (1) and ACS (1)
Technical Advances(pre-patents): 3
PublicationsHickner, Michael A.; Fujimoto, Cy H.; Cornelius, Christopher J. “Transport in
sulfonated poly(phenylene)s: Proton conductivity, permeability, and the state of water” Polymer (accepted April 18th, 2006).
Fujimoto, Cy H.; Hickner, Michael A.; Cornelius, Christopher J.; Loy, Douglas A. “Ionomeric Poly(phenylene) Prepared by Diels-Alder Polymerization: Synthesis and Physical Properties of a Novel Polyelectrolyte” Macromolecules(2005), 38(12), 5010-5016.
PresentationsFall 2006: FuelCell 2000 (2), ECS (1) and ACS (1)
Technical Advances(pre-patents): 3
20
DOE Fuel Cell Program
Critical Assumptions & IssuesHydrocarbon Membrane
1. Achieving Adequate Proton Conductivity• Proton Mobility and Acidity – current synthetic method is amenable for
inclusion of more acidic groups – current approaches are in the correct direction to achieve goal.
• Improved Morphology – improvements in structure will enhance proton conduction via better utilization of proton carrying groups to improve low RH fuel cell function.
• Interface versus Bulk - Separate MEA (interface) from PEM (bulk) to understand interrelationships. Improving proton conductivity and transport properties within the electrode (low RH & Durability).
2. Mechanical and Chemical Durability• Mechanical – Improving flexibility of PEM backbone to accommodate cyclic
stress and asymmetric water induced stresses.• Chemical – Improving stability with more chemically stable monomers
1. Achieving Adequate Proton Conductivity• Proton Mobility and Acidity – current synthetic method is amenable for
inclusion of more acidic groups – current approaches are in the correct direction to achieve goal.
• Improved Morphology – improvements in structure will enhance proton conduction via better utilization of proton carrying groups to improve low RH fuel cell function.
• Interface versus Bulk - Separate MEA (interface) from PEM (bulk) to understand interrelationships. Improving proton conductivity and transport properties within the electrode (low RH & Durability).
2. Mechanical and Chemical Durability• Mechanical – Improving flexibility of PEM backbone to accommodate cyclic
stress and asymmetric water induced stresses.• Chemical – Improving stability with more chemically stable monomers
21
DOE Fuel Cell Program
AcknowledgementsHydrocarbon Membrane – Project: FCP5
Thank you for your attention
Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company,for the United States Department of Energy under contract DE-AC04-94AL85000.
Sandia National LabsPaul Dailey
Virginia TechProfessor Eva MarandProfessor Paul DeckWill JamesBrian HickoryJessica PriceMariam Konate
ClemsonProfessor Dvora PerehiaLilin He
Case Western Reserve UniversityProfessor Morton Litt
Giner ElectrochemicalSystems, LLC
Cortney Mittelsteadt
22
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