Advanced MEAs for Enhanced Operating Conditions, Amenable ... · 2 A/cm2, and mean current density...

2006 DOE Hydrogen Program Review

Advanced MEA’s for Enhanced Operating Conditions, Amenable to High

Volume Manufacture

Mark K. Debe 3M Company May 17, 2006

Project ID # FC19

This presentation does not contain any proprietary or confidential information

Overview Timeline Barriers

• Project start 1/1/02 A. Durability

• Project end 6/30/06 B. Stack Material & Mfg Cost

• 97.5% complete C. Electrode Performance

Budget MEA Technical Targets • Total Project funding (2010)

- $6.99 million DOE • Durability w/cycling: > 5000 hrs, - $2.03 million Contractor share • Cost: $15/kW,

• Received in FY05: $1.86 million • PGM Total: 0.5 g/ kW rated • Funding for FY06: $ 0.33 million

Partners • Case Western Reserve Univ. • University of Miami • Colorado School of Mines • University of Minnesota • Dalhousie University • VAIREX Corporation • University of Illinois • Collaboration with LBNL and BNL

3 Advanced MEAs for Advanced Operating Conditions – 2006 DOE Hydrogen Program Review, May 16 – 19 2

Objectives

Overall Contract Objective Development of high performance, high durability, lower cost membrane electrode assemblies (MEA’s) qualified to meet demanding system operating conditions of higher temperature, little or no humidification, while using less precious metal catalyst.

Past Year Objectives a) Tasks 1 & 3: Demonstrate PFSA based MEA capability with: adequate

membrane and catalyst performance to meet 0.2g Pt/kW , durability to potentially operate for 5000 hours in the range of 85 < T < ~ 120ºC under sub-saturated inlet conditions with start-stop cycling, and pilot-scale production levels.

b) Task 2: Finish characterization of new proton conducting electrolytes and incorporation into membranes for operation at T > 120ºC, based on non-aqueous proton conduction mechanisms.


Plan and Approach

Tasks 1 and 3: 80 < T < 120oC MEA by roll-good processes a) Develop advanced 3M - NanoStructured Thin Film Catalysts (NSTFC) with

high performance at ultra-low Pt loadings having enhanced durability for operation over 85 < T < 120ºC with start-stop cycling, using pilot scale production capability.

b) Develop 3M PFSA membranes for operation at 85 < T < ~ 120ºC, with enhanced durability operating on low humidification and pilot scale production capability.

c) Match the 3M PEM and 3M NSTF catalyst for optimum performance, durability, and start-up.

d) Advance pilot scale process development for roll-good catalyst coated membrane (CCM) fabrication of the NSTF catalysts and 3M PEM from c).

e) Stack testing advanced MEAs from d).

Task 2: High temperature electrolytes (T > 120oC): Complete characterization of membranes comprising polymers blended with stable non-volatile 3M superacids, and new heteropolyacid additives for proton transport under hotter, drier conditions.


Current Year Technical Accomplishments - Summary

• Down-selected NSTF ternary PtCxDy catalyst for best performance and durability and demonstrated mass activity of 0.25 A/mg-Pt (at 900mV) when loading and NSTF whisker-support particle surface areas were better matched.

• NSTF catalysts shown to have significantly enhanced stability against surface area loss from Pt dissolution when compared to conventional Pt/C dispersed catalysts under both accelerated CV cycling from 0.6 to 1.2 volts, and real time, air/air start-stop durability cycles.

• NSTF catalyst support-whiskers shown to have total resistance to corrosion when held at potentials up to 1.5 volts for 3 hours.

• 3M PEM demonstrated over 5,000 hour lifetime under automotive operating conditions with load cycling at 80 oC, and 64 oC dew points.

• 3M PEM (730EW) demonstrated > 100 mS/cm conductivity at 120 oC, 80 oC DP, 250kPa.

• 3M PEM(840EW) and NSTF catalyst have been integrated for best performance, durability and fastest start-up, using all roll-good fabricated pilot scale processing.

• MEA having NSTF catalyst and 3M PEM operated for > 800 hours with cycling from 0.1 to 2 A/cm2, and mean current density of 1A/cm2 , under totally dry H2/O2, at 15 psig and 6570oC, with minimal permanent loss of performance. Still going.


Technical Accomplishments - NSTF Mass Activities

Mass and specific activities of NSTF catalysts depend on the surface area of the supporting whisker. Whisker lengths and areal number

density were controlled in first study of effect on activities.

Four Types of NSTF Whisker Supports Were Studied PE683A NSTF whisker supports

140

Whi

sker

Len

gths

(x 1

00 μ

m) ;

Num

ber/(

μm)2

120

100

80

40

20

0

Whisker Lengths Whisker Number Density

683A 686C 686B 686A

Four Types of NSTF Whisker Support Films

Examples of Two Types

PE686A NSTF whisker supports 60


Technical Accomplishments - NSTF Mass Activities

• Mass activities of NSTF ternaries are ~ 2.5 x plain NSTF Pt.

• Mass activities > 0.25 A/mg-Pt obtained with 0.08mg/cm2 PtCxDy ternary.

• Mass activities ~ same obtained with state-of-art PtxCo 1-x /C (TKK)

• Whisker support structure, and ternary composition also are factors

NSTF mass activities at 900mV, 150kPa H2/O2, are ~ 2.5 x standard Pt/C.

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.15mgPt/cm2

0.15mgPt/cm2

0.06mgPt/cm2

0.15mgPt/cm2

0.06mgPt/cm2

0.08mgPt/cm2

Whisker lengths, densities, mass activities-graph 2

PtCxDx686A

PtCxDx686A

PtCyDy683C

PtCyDy683A

PtCD*683C

Pure Pt4129(std)

Mas

s A

ctiv

ity, i

m(0

.9V)

(A/m

g Pt)

Catalyst Sample (Loading, Composition, Whisker)

Mass Activity, A/mg @ 900mV

Advanced MEAs for Advanced Operating Conditions – 2006 DOE Hydrogen Program Review, May 16 – 19 73

Better matching catalyst loading to the surface area of the NSTF whisker support film increases mass activity:

Technical Accomplishments - NSTFC Durability – CV cycling

0 3000 6000 9000

0.0

0.2

0.4

0.6

0.8

1.0

20 mV/sec0.6 - 1.2 V

75, 85,90, 95oC

65, 75, 80, 90, 95oC

NSTF Pt Catalyst0.15 mg/cm2

Pt/Carbon0.4 mg Pt/cm2

CV cycling data-graph 21

Nor

mal

ized

EC

SA

Number of CV Cycles

Normalized Surface Area versus Number of Cycles at Various Temperatures under Voltage Cycling.

0 3000 6000 9000

0.0

0.2

0.4

0.6

0.8

1.0

20 mV/sec0.6 - 1.2 V

75, 85,90, 95oC

65, 75, 80, 90, 95oC

NSTF Pt Catalyst0.15 mg/cm2

Pt/Carbon0.4 mg Pt/cm2


Nor

mal

ized

EC

SA

Number of CV Cycles

Normalized Surface Area versus Number of Cycles at Various Temperatures under Voltage Cycling.


CV’s Conditions: 20 mv/sec, T = 80oC ,Anode/Cathode: H2/N2 ,

RH:100/100%

Pt/C0.4 mg/cm2

NSTFC Pt0.15

mg/cm2-0.032

-0.024

-0.016

-0.008

0

0.008

0.016

0.024

0 0.2 0.4 0.6 0.8 1 1.2E (Volts)

I (A

mps

/cm

2 )

InitialAfter 100After 210After 350After 625After 1890

-0.0032

-0.0024

-0.0016

-0.0008

0

0.0008

0.0016

0.0024

0 0.2 0.4 0.6 0.8 1 1.2E (Volts)

I (A

mps

/cm

2 )

InitialAfter 278After 683After 1083After 1488After 1901After 2311After 3065After 3435After 4235

Pt/C

NSTF

CV changes from Pt/C during 1890 cycles, and (bottom) NSTF MEA through 4235 cycles.

• Pt/C polarization curves show significant performance degradation after 2429 cycles at 80oC. ECSA drops 90% from 297 to 33 cm2/cm2.

• NSTF polarization curves show much less performance loss after 4225 cycles at 80oC. ECSA drops 20% from 13.2 to 10.4 cm2/cm2.

0.0 0.2 0.4 0.6 0.8 1.0 1.20.0

0.2

0.4

0.6

0.8

1.0

Changes after 4225 Cycles * Cathode ESCA: - 20% * Specific Activity: -15% * H-Pump (150% RH): 0 % * Mass Transport: ~ 0% (23psig, GDS)

NSTF Pt (0.15 / 0.15 mg/cm2)3M PEM and GDL

Initialperformance

After 4225cycles at 80oC

Tcell = 75°, 0/0 psig H2/airConstant flow H2/air: 800/1800 sccmHumidity = 100%/100% RHPDS(0.85,0.25,0.48,10s/pt),PSS(0.4V,5min)

FC10933-graph 3

Cel

l Vol

tage

(V)

Current Density (A/cm²)0.0 0.2 0.4 0.6 0.8 1.0 1.2

0.0

0.2

0.4

0.6

0.8

1.0

Changes after 2429 Cycles * Cathode ESCA: - 90%

Pt/Carbon (0.4/0.4 mg/cm2)3M PEM and GDL

Initialperformance

After 2429cycles at 80oC

Tcell = 75°, 0/0 psig H2/airConstant flow H2/air: 800/1800 sccmHumidity = 100%/100% RHPDS(0.85,0.25,0.48,10s/pt),PSS(0.4V,5min)

FC10814-graph 1

Cel

l Vol

tage

(V)

Current Density (A/cm²)

Technical Accomplishments - NSTF Durability – CV cycling

2.72 2.76 2.80 2.84 2.88 2.92 2.96

-9.0

-8.5

-8.0

-7.5

-7.0


=> Ea = 22.6 + 3.6 kJ/mole

Pt/C, 0.40 mg/cm2

Y = 0.47 - (2.72 + 0.43) X

=> Ea = 52 + 8 kJ/mole

NSTF Pt, 0.15 mg/cm2

Y =9.05 - (6.28 + 0.91) X

Ln(-

k )

= Ln

(G) -

Ea/R

1000/T (oK)

First Order Kinetic Rate Model of Surface Area Loss:NSTF = 52 kJ/mole vs. Pt/C = 23 kJ/mole


Technical Accomplishments - NSTF Durability – CV cycling

Summary of CV Cycling Comparisons • NSTF-Pt catalysts (0.15 mgPt/cm2) are much more resistant to loss of

surface area from high voltage cycling than are Pt/Carbon (Ketjen Black) with 0.4 mg Pt/cm2 loading.

• The NSTF-Pt asymptotically approaches a maximum of ~ 33% surface area loss in 9000 cycles, while the Pt/C loses ~ 90% of the initial surface area in 2000 cycles

• The activation energy for surface area loss is twice as high for NSTF (52 vs 23kJ/mole) reflecting a slower rate of surface area loss for NSTF.

• The surface area loss appears to be primarily by agglomeration. Surface Area loss of Pt/C = 90%/2500 cycles, versus NSTF = 20%/4225 cycles

• Both anode and cathode Pt/C crystallite sizes increase 380% and 300%, but the NSTF crystallite sizes increase only ~ 10% and 68% respectively.

• The increased Pt/C particle size does not increase catalyst specific activity or catalyst utilization to equal that of the NSTF.


Technical Accomplishments – NSTFC Stop/Start Durability

0

2

/

�

�

�

• H2/air cycled to anode

• oC

• cell1 A/cm2

• correlates with change seen with CV cycling

Weekend Shut-down

Cell voltage at 1 A/cm2

Same Pt loading Same 3M PEM Same 3M GDL

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Cel

l Vol

tage

at 1

A/c

m

Pt Carbon MEA

NSTFC MEA

Real-time Cycling Test to Simulate Automotive Stop-Start

NSTF significantly more stable than Pt/C – consistent with Accelerated CV cycling

NSTF Performance loss after 300 cycles is reversible, not permanent like for Pt/C

XRD and CV ECSA imply NSTF catalyst crystallite sizes are increased by SS-cycling.

Proprietary protocol –

~ 20 min./ cycle • T = 80

Stopping and cooling recovers all NSTFC

performance. ~ -20% loss of ECSA

and restart

vs. Cycle Number The data on this page were generated at 3M expense.

0 50 100 150 200 250 300• Pt/Carbon performance

Cycle Number not recoverable.


Pt/C ECSA and Performance Decay Significantly after just 30 minutes at 1.5 V.

Applied Voltage = 1.5 V; 500 sccm H2 / N2 on An/Cat; Cell T = 80oC ; %RH: 100%

Carbon Corrosion

No Carbon

to Corrode

0 300

50100150200250300

EC

SA

(cm

2 /cm

2 )

Time at 1.5 Volts (minutes)

Pt/C50wt%Pt onKetjen black

Technical Accomplishments – NSTF Support Durability

0 30 60 90 120 150 18002468

1012

EC

SA

(cm

2 /cm

2 )

Time at 1.5 Volts (minutes)

NSTF - Pt

00.10.20.30.40.50.60.70.80.9

1

0 0.2 0.4 0.6 0.8 1 1.2J (A/cm2)

V (v

olts

)

FC10766-319 - Initial Performance

FC10766-448 - After 90 min at 1.5V

FC10766-478 - After 180 min at 1.5V

75C cell, 0/0 psig inlet, H2/airCF800/1800 sccm, counterflow.Humidity: 50%/50%PDS(0.85,0.25,0.048,10s/pt)

NSTF ECSA and Performance Show No Decay After 3 Hours at 1.5 V.

NSTF-Pt

0.15 mg Pt/cm2

00.10.20.30.40.50.60.70.80.9

1

0 0.2 0.4 0.6 0.8 1 1.2J (A/cm2)

V (v

olts

)

FC10794-96 - Initial PerformanceFC10794-122 - After 30 min at 1.5V

75C cell, 0/0 psig inlet, H2/airCF800/1800 sccm, counterflow.Humidity: 50%/50%PDS(0.85,0.25,0.048,10s/pt)

0.4 mg Pt/cm2

Advanced MEAs for Advanced Operating Conditions – 2006 DOE Hydrogen Program Review, May 16 – 19 123The data on this page were generated at 3M expense.

Technical Accomplishments – PEM Durability

Under load-cycling tests, the 3M PEM has demonstrated > 5000 hours lifetime, where failure is defined when V(0.02 A/cm2) becomes < 800 mV.

Utilizing a multi-cell test station, several MEAs are run in separate cells in

Cell Temperature: 80 oC Inlet Dew points: 64/64 oC Outlet Pressures: 175kPa

1.7201.008

5200.207

1.7150.806

15200.025

3100.804

1.7150.803

15200.022

550.201

Stoich.

Duration(m

in)

J(A

/cm2)

TestP

oint

2

3

continuous fashion under the following conditions:

Measured with Pt/Carbon Dispersed Catalysts: 0.4/0.4 mg-Pt /cm

The data on this page were generated at 3M expense.


Proton Conductivity as a function of pressure at 120oC, (water content = 80˚C DP at 250 kPa)

0.000

0.020

0.040

0.060

0.080

0.100

0.120

50 100 150 200 250 300Pressure, kpa

S/cm

730 EW 830 EW

N 112

DOE 2010 target for conductivity

at 120oC.

DOE 2010 target for conductivity

at 120oC.

Technical Accomplishments – PEM Conductivity

3M PEM with 730 EW meets the DOE 2010 target for membrane conductivity at 120oC.



Technical Accomplishments – Membrane Performance - Hot and Drier

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 1.4Current Density (A/cm2)

V

730 EW 3MCast 1000 EW Nafion3M 730 impNafion imp

Fuel cell performance is much higher for lower EW membranes under hot, dry conditions.

0

0.2

0.4

0.6

0.8

1

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6Current Density (A/cm2)

V

730 EW 3MCast 1000 EW Nafion3M 730 impNafion imp

730 EW ionomer, 120˚ C, 250 kPa, 10 % RH

730 EW ionomer, 120˚ C,250 kPa, 20 % RH



Technical Accomplishments – Real Time Durability Test

• NSTF PtCxDy ternary and 3M PEM based MEA.• Totally dry H2/O2, 200 kPa, 65-70 oC. • 1 hour repetitive GSS (0.7 or 0.9 A/cm2) and GDS scans (0.1-2 A/cm2): Mean J =0.99 A/cm2

• Stop, cool for 1.5 hours, and restart every 100 - 125 hours fully recovers performance• Over 1400 cycles between ~ 0.87V and ~ 0.5 V in 820 hours.


NSTF/3M PEM MEA durability test under dry H2/O2 with periodic cycling: Loss of –11μV/hr at 1 A/cm2 over 815 hours through 4/20/06 (still running).

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.00.0

0.2

0.4

0.6

0.8

1.0

Time averaged current density over each GDS/GSS cycle = 0.992 A/cm2.

65- 70 oC cell. 15/15 psig. H2/O2, 50 cm2Quad SerpentineCS: 1.3/2.0 counterflowHumidity: 0%/0% No water added at any timeGDS(0.1,2.0,0.048,180s), GSS(0.7 A/cm2,10min)

FC11419vs2-graph 8

Cel

l Vol

tage

(V)

J (A/cm2)

Cell Voltage, 820 hours Cell Voltage, 585 hours Cell Voltage, 392 hours Cell Voltage, 280 hours Cell Voltage, 176 hours

GDS Polarization Curves Over TimeGSS-Log Plot

0 100 200 300 400 500 600 700 800 900 10000.0

0.2

0.4

0.6

0.8

1.0

Back to GSS0.7 A/cm2

Change to GSS 0.9 A/cm2

Time averaged current density over each GDS/GSS cycle = 0.992 A/cm2.

65 - 70 oC cell. 15/15 psig. H2/O2, 50 cm2Quad SerpentineCS: 1.3/2.0 counterflowHumidity: 0%/0% No water added at any timeGDS(0.1,2.0,0.048,180s), GSS(0.7 A/cm2,10min)

-313 μV/HrReversible

Decay

~1.5 hourshut-downs

Week-endshut-down

FC11419-graph 7

GSS

Cel

l Vol

tage

at C

urre

nt D

ensi

ty A

/cm

2

Time (Hours)

J(A/cm2) Cell Voltage

~ 7 mV Loss at 1 A/cm2

from 176 hrs to 815 hours


Technical Accomplishments - NSTF CCM Scale-up

Conclusions: • All process steps in NSTF CCM roll-good fabrication have broad parameter

windows

• Pilot line fabricated roll-good CCM performance matches hand-formed MEA’s.

• MEA components are all manufacturable by high volume methods. 1.0

0.9

TcellH2/aiH2/ai

i

i

23 psig, 60%

7.5 pisg, 60%

= 80°C r stoich = 2.0/2.5 r pressure = as stated

Humidity = as stated Galvanostat c Scan: 180 seconds/pt

30 psig, 60%

15 ps g, 60%

7.5 pisg, 100%

• Roll-good MEA, tested 0.8

as fabricated, made with 0.7 C

ell V

olta

ge (V

)

NSTF PtCD catalyst at 0.6

0.5 0.2mg/cm2 on cathode and 3M 980EW PEM, 0.4

can hit 1.5 A/cm2 at 0.3

0.2 600mV under 250kPa

0.1

H2/air. 0.0

The data on this page were generated at 3M expense. 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0

J (A/cm2)

3 Advanced MEAs for Advanced Operating Conditions – 2006 DOE Hydrogen Program Review, May 16 – 19

FC11557-graph9

17

Project Summary and Future Work Relevance: Has demonstrated the feasibility for achieving the 2010 durability, performance and

cost targets specified by DOE with MEA’s designed for high volume manufacturability.

Technical Accomplishments and Progress: Project has met its objectives by demonstrating that a) non-carbon supported, thin film catalysts can simultaneously achieve high mass activities and high durability under stop-start and high potential conditions, b) PEM lifetimes under load-cycling can exceed 5000 hrs, and PEM conductivities can remain high under hot, dry operating conditions.

Technology Transfer/Collaborations: Active interactions with automotive fuel cell system integrators have specified performance and durability tests for membrane, catalyst and catalyst supports that were used to demonstrate significant enhancements of the approach in these areas.

Remaining Work on This Project: • Complete short stack testing (3-5 kW) in automotive quality stack, and deliver to Argonne

National Laboratory for evaluation: (by June 30, 2006) • Complete and submit final report: (by Sept. 30, 2006)

Proposed Future Research: Further optimize NSTF multi-element catalysts and supports for mass activities approaching entitlement values and further enhanced corrosion resistance. Integrate the NSTF catalysts with tailored membranes designed for hotter, drier conditions and optimized GDL’s.


Project Summary- NSTF Cat. Characteristics vs DOE Targets Table 3.4.13. [1] Technical Targets: Electrocatalysts for Transportation Applications

Characteristic Units 2010/2015 Stack Targets

3M 2006 Status (50 cm2 cell)

PGM Total Content g/kW rated in stack

0.5 / 0.4 0.33 for V < 0.72 volts

PGM Total Loading mg PGM/cm2

electrode area 0.3 / 0.2 0.21

PGM Cost $/kW @ $15/g 8 / 6 6

Durability with cycling At operating T < 80oC At operating T > 80oC

Hours 5000 2000

TBD under specified

conditions

Mass Activity (150kPa H2/O2 80oC. 100% RH)

A/mg-Pt @ 900 mV

0.44 / 0.44 0.25

Specific Activity (150kPa H2/O2 80oC. 100% RH)

μA/cm2-Pt @ 900 mV,

720 / 720 2,470 (0.08 mg-Pt/cm2)

ECSA loss by Stop/Start % ECSA loss < 40 30 (Per protocol of slides 8 or 11)

Electrochemical support loss at high potentials

mV after 100 hrs @ 1.2 V

< 40 < 10 projected (Per protocol of slide 12)


Project Summary- 3M PEM Characteristics vs DOE Targets Table 3.4.12. [1] Technical Targets: Membranes for Transportation Applications

Characteristic Units 2010/2015 Target

3M 2006 Status (50 cm2 cell)

Membrane Conductivity at: S/cm 0.10 / 0.10 > 0. 10 @ 120oC Operating Temperature w/ 80oC DP, 250kPa,

Room Temperature S/cm 0.07 / 0.07 0.12 saturated -20 oC S/cm 0.01/ 0.01 TBD

Operating Temperature oC < 120 ≤ 120

Inlet water vapor partial pressure

kPa (absolute) 1.5 / 1.5 TBD

Oxygen cross-over mA/cm2 2 / 2 Expected to be similar for PFSA

Hydrogen cross-over mA/cm2 2 / 2 < 2 @ 70 oC, saturated

Durability with load cycling

Hours, T < 80 oC Hours, T > 80 oC

5000 2000 / 5000

> 5000 > 4,000

[1] DOE HFCIT Multi-Year Research, Development and Demonstration Plan


Publications & Presentations 1. M. K. Debe, A. K. Schmoeckel, G. D. Vernstrom and R. Atanasoski, “High Voltage Stability of NanoStructured Thin Film

Catalysts for PEM Fuel Cells,” submitted J. Power Sources, March, 2006, and presented 2005 Fuel Cell Seminar, Palm Springs, California, Nov. 14 - 18, 2005.

2. M. K. Debe, A. K. Schmoeckel, S. M. Hendricks, G. D. Vernstrom, G. M. Haugen and R. T. Atanasoski, “Durability Aspects of Nanostructured Thin Film Catalysts for PEM Fuel Cells,” presented at Symposium on Durability and Reliability of Low-Temperature Fuel Cell Systems, 208th ECS meeting, Oct. 16 - 21, 2005, Los Angeles, CA.

3. J. McBreen, M. Balasubramanian, W.-S. Yoon, K. Y. Chung, H. S. Lee, and X. Q. Yang, R.T.Atanasoski, A.K. Schmoeckel, G.D. Vernstrom, and M.K. Debe, “PEM Fuel Cells: Materials Issues,” Fifth International Symposium on Proton Exchange Membrane Fuel Cells, In Honor of Dr. Subramanian Srinivasan, 208th ECS Meeting, Los Angeles, CA, Oct. 16 - 21, 2005.

4. J.R. Dahn, D.A. Stevens, A. Bonakdarpour, E.B. Easton, M.T. Hicks, G.M. Haugen, R.T. Atanasoski and M.K. Debe, “Development of Durable and High-Performance Electrocatalysts and Electrocatalyst Support Materials,” Symposium on Durability and Reliability of Low-Temperature Fuel Cell Systems, 208th ECS meeting, Oct. 16 - 21, 2005, Los Angeles, CA.

5. F. Meng, S. Dec, M. Frey, S. Hamrock, J. Turner, and A. Herring, "Spectroscopic Studies of Heteropoly Acid doped 3M Perfluorinated Sulfonic Acid Polymer Membranes," 208th Meeting of the Electrochemical Society, Los Angeles, CA, Oct. 18, 2005. A paper of the same title was also submitted to Proceeding of the Electrochemical Soc.

6. S. Hamrock, "The Development of New PEM Fuel Cell Membranes at 3M," Golden Gate Polymer Forum, 25th Anniversary Symposium, Oct. 23, 2005, San Francisco, CA.

7. A. M. Herring, J. A. Turner, S. F. Dec, F. Meng, J. Horan, N. Aieta, R. J. Stanis, "The Use of Heteropoly Acids in the Production of High Performance PEM Fuel Cell Components," 2005 Fuel Cell Seminar, Nov. 15, Palm Springs, CA.

8. S. Hamrock, "New PFSA membranes with Improved Durability," Pacific Polymer Conference IX, Maui, Hawaii, Dec. 12, 2005. 9. M. K. Debe, “Advanced Catalyst and Membrane Technology with Enhanced Performance and Durability for Automotive

Requirements,” at 4th Internationa. Fuel Cell Workshop 2005, Kofu, Japan, Sept. 23-24, 2005. 10. A. Herring, J. Turner, S. Dec, J. Malers, F. Meng, J. Horan and N. Aieta,“The Use of Heteropoly Acids in Composite

Membranes for Elevated Temperature or Low Humidity PEM Fuel Cell Operation,” 2nd International Conference on Polymer Batteries and Fuel Cells, Las Vegas, NV, June 13, 2005.

11. M. A. Yandrasits,“Mechanical Property Measurements of PFSA Membranes at Elevated Temperatures and Humidities,” 2nd International Conference on Polymer Batteries and Fuel Cells, Las Vegas, NV, June 14th 2005.

12. M. K. Debe,“Prospects and Challenges for PEM Fuel Cells with a Focus on MEA Development for Automotive Applications,” Invited Plenary Lecture, 2005 Annual Meeting of the North American Membrane Society, Providence, RI, June 15, 2005.


Critical Assumptions and Issues 1) Stack testing of the NSTF MEAs currently underway will be using a 3.5 to 5kW short-

stack version of a new design that has not previously been tested with this or any type of MEA. It is a short stack version of full 70kW automotive prototype, meeting stringent power density (volumetric and gravimetric) targets. It requires full 7-layer MEA’s with integrated gaskets for proper operation. Development of the methodologies to make 7-layer NSTF MEA’s is being done for the first time, and outside the contract, to enable the stack testing. There is very little time left in the contract to work out issues that might arise by the combination of these new 7-layer MEAs and new stack design.

2) Work on stack testing has been delayed for two reasons. First we waited until the new automotive stack hardware was finally available, which did not occur until early April, 2006. Second, we have delayed in order to incorporate the best and latest version of an integrated MEA containing the 3M NSTF catalyst and 3M PEM combination. These MEA’s will be roll-good fabricated on a very tight schedule on pilot production equipment to just match the readiness of the new stack. This timing will only allow 2 to 3 stack builds and evaluations before the end of the contract June 30, 2006, by which time it must be delivered to Argonne National Lab. There is little if any time for solving any problems.

3) The latest and best MEA roll-good components to be used in the stack testing will be fabricated on actual production equipment. If there are delays due to scheduling conflicts or equipment failures, then again we may not make the desired time-line.


Advanced MEAs for Enhanced Operating Conditions, Amenable ... · 2 A/cm2, and mean current density...

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