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1

Kyu Cho  

NLE Websites -- All DOE Office Websites (Extended Search)

Kyu Cho Kyu Cho Electrochemical Technologies Group Lawrence Berkeley National Laboratory 1 Cyclotron Road MS 70-108B Berkeley CA 94720 Office Location: 70-0189A (510) 486-6590 KTCho@lbl.gov Kyu Taek Cho worked as a senior researcher in Hyundai Motor Company, South Korea to develop fuel cell stacks for automotive application for around 10 years, and he continued on fuel cell research to obtain a Ph.D. for the study of multiphase porous media flow from Pennstate University. In LBNL, he has been working as a Principal Research Associate to develop a cost-effective flow battery system by utilizing hydrogen and bromine as redox couple since 2010. Seminars 1. K. T. Cho, Markus S Ding, Adam Z. Weber, Vince Battaglia and Venkat Srinivasan, 'Effect of Operating Condition On Cyclic

2

Ahmet Kusoglu  

NLE Websites -- All DOE Office Websites (Extended Search)

Ahmet Kusoglu Ahmet Kusoglu Electrochemical Technologies Group Lawrence Berkeley National Laboratory 1 Cyclotron Road MS 70-108B Berkeley CA 94720 Office Location: 70-0189 (510) 486-6590 AKusoglu@lbl.gov Ahmet Kusoglu is currently a post-doctoral fellow in the Electrochemical Technologies group working on fundamental understanding of polymer materials for electrochemical energy devices. Ahmet hold B.S. and Ph.D. in Mechanical Engineering, the latter of which was received from University of Delaware, where he studied the mechanical characterization and durability of ionomer membranes and earned a graduate fellowship award. His current research involves modeling the degradation and failure mechanisms, transport phenomena and structure/function/performance relationships in

3

Publications  

NLE Websites -- All DOE Office Websites (Extended Search)

4 results: 4 results: BibTex RIS RTF XML Sort by: Author Title Type [ Year (Desc) ] Filters: Keyword is conductivity [Clear All Filters] 2013 Kusoglu, Ahmet, Kyu Taek Cho, Rafael A. Prato, and Adam Z. Weber. "Structural and transport properties of Nafion in hydrobromic-acid solutions." Solid State Ionics (2013). 2012 Kusoglu, Ahmet, Alexander Hexemer, Ruichun Jiang, Craig S. Gittleman, and Adam Z. Weber. "Effect of compression on PFSA-ionomer morphology and predicted conductivity changes." Journal of Membrane Science 421-422 (2012): 283-291. 2010 Braun, Artur, Bongjin S. Mun, Yun Sun, Z. Liu, Oliver Gröning, R. Mäder, Selma Erat, Xueyuan Zhang, Samuel S. Mao, Ekaterina Pomjakushina et al. "Correlation of conductivity and angle integrated valence band

4

Ahmet Kusoglu  

NLE Websites -- All DOE Office Websites (Extended Search)

Mechanical Engineering, University of Delaware Links Best Poster Paper Award at the 2012 Fuel Cell Science and Technology Grove Conference, Berlin LinkedIn profile Google Scholar...

5

ESS 2012 Peer Review - Hydrogen-Bromine Flow Batteries for Grid-Scale Energy Storage - Vincent Battaglia, LBNL  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

H H 2 /Br 2 Flow Battery for Grid-Scale Energy Storage Venkat Srinivasan, Adam Weber, & Vince Battaglia Lawrence Berkeley National Laboratory * DOE ESS Review * Washington, DC * September 26, 2012 vsbattaglia@lbl.gov Purpose Develop a low-cost, energy-storage system with high power density at 80% efficiency Use H 2 and Br 2 in a flow battery Future Plans Modeling Funding from ARPA-E GRIDS, USDOE LBNL: Kyu Taek Cho (Cell studies); Paul Ridgway (Catalysis studies); Sophia Haussener (Transport modeling) Bosch: Paul Albertus (Cost Modeling); Roel Sanchez-Carrera and Boris Kozinsky (Catalyst theory)

6

Security and Smart Metering Sophia Kaplantzis and Y. Ahmet Sekercioglu  

E-Print Network (OSTI)

! Architecture US!NIST! Smart!Grid! Interoperability! Roadmap 1990 1995 2000 20102005 Smart!Grid! Demonstration!the!University!of!Minnesota!campus.! ­ Conduct!"wind"tunnel" data"driven!simulation!testing!of!smart! grid!designs,!alternative!architectures/H.W.!Sweatt!Chair!in!Technological!Leadership Professor,!Electrical &!Computer!Engineering! University!Distinguished!Teaching!Professor Smart!Grid

Sekercioglu, Y. Ahmet

7

Publications  

NLE Websites -- All DOE Office Websites (Extended Search)

4 results: 4 results: BibTex RIS RTF XML Sort by: Author Title Type [ Year (Desc) ] Filters: Author is Paul L. Ridgway [Clear All Filters] 2012 Ridgway, Paul L., Honghe Zheng, A. F. Bello, Xiangyun Song, Shidi Xun, Jin Chong, and Vincent S. Battaglia. "Comparison of Cycling Performance of Lithium Ion Cell Anode Graphites." Journal of The Electrochemical Society 159, no. 5 (2012): A520. Cho, Kyu Taek, Paul L. Ridgway, Adam Z. Weber, Sophia Haussener, Vincent S. Battaglia, and Venkat Srinivasan. "High Performance Hydrogen/Bromine Redox Flow Battery for Grid-Scale Energy Storage." Journal of the Electrochemical Society 159, no. 11 (2012): A1806-A1815. 2010 Delacourt, Charles, Paul L. Ridgway, and John S. Newman. "Mathematical Modeling of CO[sub 2] Reduction to CO in Aqueous Electrolytes." Journal of

8

A Unified Framework for Monitoring Data Streams in Real Time Ahmet Bulut and Ambuj K. Singh  

E-Print Network (OSTI)

-energy photons) over a certain time period, which indicates the existence of a Gamma Ray Burst. If we know monitoring queries, such as finding surprising levels of a data stream, detecting bursts, and to (2- priate lengths a priori. For example, bursts of events can occur at variable temporal modalities from

California at Santa Barbara, University of

9

Optimization Online - Two-Stage Decomposition Algorithms for ...  

E-Print Network (OSTI)

Sep 21, 2013 ... exxonmobil.com) Ahmet Keha(ahmet.b.keha ***at*** exxonmobil.com) George Nemhauser(gnemhaus ***at*** isye.gatech.edu)

10

High Performance Hydrogen/Bromine Redox Flow Battery for Grid-Scale Energy  

NLE Websites -- All DOE Office Websites (Extended Search)

High Performance Hydrogen/Bromine Redox Flow Battery for Grid-Scale Energy High Performance Hydrogen/Bromine Redox Flow Battery for Grid-Scale Energy Storage Title High Performance Hydrogen/Bromine Redox Flow Battery for Grid-Scale Energy Storage Publication Type Journal Article Year of Publication 2012 Authors Cho, Kyu Taek, Paul L. Ridgway, Adam Z. Weber, Sophia Haussener, Vincent S. Battaglia, and Venkat Srinivasan Journal Journal of the Electrochemical Society Volume 159 Issue 11 Pagination A1806 - A1815 Date Published 01/2012 ISSN 0013-4651 Keywords hydrogen/bromine, redox flow battery Abstract The electrochemical behavior of a promising hydrogen/bromine redox flow battery is investigated for grid-scale energy-storage application with some of the best redox-flow-battery performance results to date, including a peak power of 1.4 W/cm(2) and a 91% voltaic efficiency at 0.4 W/cm(2) constant-power operation. The kinetics of bromine on various materials is discussed, with both rotating-disk-electrode and cell studies demonstrating that a carbon porous electrode for the bromine reaction can conduct platinum-comparable performance as long as sufficient surface area is realized. The effect of flow-cell designs and operating temperature is examined, and ohmic and mass-transfer losses are decreased by utilizing a flow-through electrode design and increasing cell temperature. Charge/discharge and discharge-rate tests also reveal that this system has highly reversible behavior and good rate capability.

11

High-Speed Internet Access via HVAC Ducts: A New Approach Daniel D. Stancil, Ozan K. Tonguz, Ariton Xhafa, Ahmet Cepni, and Pavel Nikitin  

E-Print Network (OSTI)

High-Speed Internet Access via HVAC Ducts: A New Approach Daniel D. Stancil, Ozan K. Tonguz, Ariton conditioning (HVAC) ducts for indoor wireless transmission systems and networks. Mea- surements and system to 100 Mbps should be possible, when HVAC system is used in con- junction with OFDM technology. Keywords

Stancil, Daniel D.

12

Fabrication and Testing  

Science Conference Proceedings (OSTI)

Aug 6, 2010 ... Fabrication of Artificial Bone by the Combination of Electrospinning, Extrusion and Slurry Processes: Hiep Nguyen1; Byong-Taek Lee1;...

13

Advanced ODS Alloys  

Science Conference Proceedings (OSTI)

Mar 5, 2013... Byun2; Seong Woong Kim1; chan hee park1; Jong Taek Yeom1; 1Korea Institute of Materials Science; 2Oak Ridge National Laboratory

14

Effect of Al+B4C Agglomerate Size on Mechanical Properties of ...  

Science Conference Proceedings (OSTI)

Author(s), Bo Yao, Travis J. Patterson, Yongho Sohn, Matthew Shaeffer, Cory Smith, Mark van den Bergh, Kyu Cho. On-Site Speaker (Planned), Bo Yao. Abstract...

15

Composites for Structural and Multifunctional Applications  

Science Conference Proceedings (OSTI)

Oct 8, 2012 ... Room: Room 414. Location: David L. Lawrence Convention Ctr Session Chair: Kyu Cho, US Army Research Laboratories; Amit Misra, LANL...

16

Semi-continuous network flow problems  

E-Print Network (OSTI)

Apr 26, 2012 ... Acknowledgements: The authors acknowledge ExxonMobil for support, and Myun-Seok Cheon and. Ahmet Keha for useful discussions. 29...

17

Publications  

NLE Websites -- All DOE Office Websites (Extended Search)

Kusoglu, Ahmet, and Adam Z. Weber. "Water Transport and Sorption in Nafion Membrane." In ACS Symposium SeriesPolymers for Energy Storage and Delivery: Polyelectrolytes for...

18

Publications  

NLE Websites -- All DOE Office Websites (Extended Search)

Hexemer Clear All Filters 2012 Kusoglu, Ahmet, Alexander Hexemer, Ruichun Jiang, Craig S. Gittleman, and Adam Z. Weber. "Effect of compression on PFSA-ionomer morphology and...

19

Effect of Compression on Conductivity and Morphology of PFSA...  

NLE Websites -- All DOE Office Websites (Extended Search)

Number LBNL-5383E Year of Publication 2011 Authors Kusoglu, Ahmet, Ruichun Jiang, Craig S. Gittleman, and Adam Z. Weber Conference Name 242nd ACS National Meeting &...

20

Water Transport and Sorption in Nafion Membrane  

NLE Websites -- All DOE Office Websites (Extended Search)

Transport and Sorption in Nafion Membrane Title Water Transport and Sorption in Nafion Membrane Publication Type Book Chapter Year of Publication 2012 Authors Kusoglu, Ahmet, and...

Note: This page contains sample records for the topic "ahmet kyu taek" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Publications  

NLE Websites -- All DOE Office Websites (Extended Search)

Suchol Savagatrup Clear All Filters 2012 Kusoglu, Ahmet, Suchol Savagatrup, Kyle Clark, and Adam Z. Weber. "Role of Mechanical Factors in Controlling the Structure-Function...

22

Role of Mechanical Factors in Controlling the Structure-Function...  

NLE Websites -- All DOE Office Websites (Extended Search)

Article Year of Publication 2012 Authors Kusoglu, Ahmet, Suchol Savagatrup, Kyle Clark, and Adam Z. Weber Journal Macromolecules Volume 45 Issue 18 Pagination 7467 - 7476...

23

Investigation of 5 MOL% YSZ Electrolyte for SOFC  

Science Conference Proceedings (OSTI)

Presentation Title, Investigation of 5 MOL% YSZ Electrolyte for SOFC. Author(s), Nilufer Evcimen, Ahmet Ekerim. On-Site Speaker (Planned), Nilufer Evcimen.

24

Compression and Hydration Effects of PFSA Membranes  

NLE Websites -- All DOE Office Websites (Extended Search)

Year of Publication 2011 Authors Kusoglu, Ahmet, and Adam Z. Weber Conference Name 9th European Symposium on Electrochemical Engineering Conference Location Crete Greece...

25

Publications  

NLE Websites -- All DOE Office Websites (Extended Search)

of PFSA Membranes In 9th European Symposium on Electrochemical Engineering. Crete Greece, 2011. Kusoglu, Ahmet, Ruichun Jiang, Craig S. Gittleman, and Adam Z. Weber. Effect of...

26

Electronic Packaging and Interconnection Materials Committee  

Science Conference Proceedings (OSTI)

... Materials: Organized by Andre Lee; Fay Hua; Tae-Kyu Lee; John Elmer; Yan Li ; Robert Kao; Fan-yi Ouyang; Chang-Woo Lee; Won Sik Hong; Heugel Werner.

27

Doubling Estimates of Light Elements in the Earth's Core | Advanced...  

NLE Websites -- All DOE Office Websites (Extended Search)

answer the long-standing question of the composition of the Earth's core. - Karen Fox See: Zhu Mao1*, Jung-Fu Lin1, Jin Liu1, Ahmet Alatas2, Lili Gao2, Jiyong Zhao2, and...

28

Publications  

NLE Websites -- All DOE Office Websites (Extended Search)

BibTex RIS RTF XML Sort by: Author Title Type Year (Desc) Filters: Author is Kyle Clark Clear All Filters 2012 Kusoglu, Ahmet, Suchol Savagatrup, Kyle Clark, and Adam Z....

29

Water Uptake of Fuel-Cell Catalyst Layers  

NLE Websites -- All DOE Office Websites (Extended Search)

Water Uptake of Fuel-Cell Catalyst Layers Title Water Uptake of Fuel-Cell Catalyst Layers Publication Type Journal Article Year of Publication 2012 Authors Kusoglu, Ahmet, Anthony...

30

Browse by Discipline -- E-print Network Subject Pathways: Energy Storage,  

Office of Scientific and Technical Information (OSTI)

Q R S Q R S T U V W X Y Z Pachucki, Krzysztof (Krzysztof Pachucki) - Instytut Fizyki Teoretycznej, Uniwersytet Warszawski Packard, Richard E. (Richard E. Packard) - Department of Physics, University of California at Berkeley Padgett, Miles (Miles Padgett) - Department of Physics and Astronomy, University of Glasgow Padmanabhan, Janardhan (Janardhan Padmanabhan) - Astronomy and Astrophysics Division, Physical Research Laboratory, Ahmedabad Page, John (John Page) - Department of Physics and Astronomy, University of Manitoba Paiella, Roberto (Roberto Paiella) - Department of Electrical and Computer Engineering, Boston University Painter, Oskar (Oskar Painter) - Department of Applied Physics and Materials Science, California Institute of Technology Pak, Hyuk Kyu (Hyuk Kyu Pak) - Department of Physics, Pusan National

31

Power-Factor and Torque Calculation with Consideration of Cross Saturation of the Interior Permanent Magnet Synchronous Motor with  

E-Print Network (OSTI)

Permanent Magnet Synchronous Motor with Brushless Field Excitation Seong Taek Lee1,2 , Timothy A. Burress1 permanent magnet synchronous motor (IPMSM). The conventional two-axis IPMSM model is modified to include motor of a hybrid electric vehicle. I. INTRODUCTION The interior permanent magnet synchronous motor

Tolbert, Leon M.

32

Graphene coating makes carbon nanotube aerogels superelastic and resistant to fatigue  

E-Print Network (OSTI)

Graphene coating makes carbon nanotube aerogels superelastic and resistant to fatigue Kyu Hun Kim-based foams10­14 and aero- gels15,16 . However, all nanotube-based foams and aerogels devel- oped so far10,11,13,14 when they are subjected to cyclic strain. Here, we show that an inelastic aerogel made

Islam, Mohammad F.

33

Brewing Renewable Diesel | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Brewing Renewable Diesel Brewing Renewable Diesel Discovery & Innovation Stories of Discovery & Innovation Brief Science Highlights SBIR/STTR Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 11.15.11 Brewing Renewable Diesel Researchers at a DOE Bioenergy Research Center use microbes to synthesize a drop-in replacement for standard diesel transportation fuel. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo Pamela Peralta-Yahya, Taek Soon Lee, and Mario Ouellet of the DOE Joint BioEnergy Institute team that used microbes to synthesize a bio-based drop-in substitute for diesel fuel. Photo by Roy Kaltschmidt, Berkeley Lab From left, Pamela Peralta-Yahya, Taek Soon Lee, and Mario Ouellet of the

34

Remediation of Abandoned Mines Using Coal Combustion By-Products  

E-Print Network (OSTI)

Remediation of Abandoned Mines Using Coal Combustion By-Products Sowmya Bulusu1 ; Ahmet H. Aydilek that occurs when pyrite that is present in abandoned coal mines comes in contact with oxygen and water, which subject headings: Remedial action; Acid mine water; Mines; Coals; Recycling; Maryland; Fly ash

Aydilek, Ahmet

35

Microsoft PowerPoint - Proceedings Cover Sheets  

NLE Websites -- All DOE Office Websites (Extended Search)

Capture - Capture - Membranes (2) Energy Analysis of CO 2 Separation Process with Hollow Fiber Membrane Using ASPEN Simulation Method Hyung-Taek Kim and Hyun-Min Shim Dept. of Energy Studies Ajou University, Suwon Korea Contents Background Purpose of the Study Simulation & Analysis Method Schematic of Process Results of Simulation Conclusion Future Work Background * Carbon Dioxide (CO 2 ) - Major source of greenhouse gas from Power Plant & Industrial Process - CO 2 Emission : Korea ranked 10 th in the world - Kyoto Protocol : Expected to add carbon tax, emission trade * For sustainable development, Korea must prepare for the duty for reduction of CO 2 emission. * Methods of CO 2 separation : Absorption, Adsorption, Membrane - Absorption : Low conc. CO 2 recovery process & large scale

36

2011 | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Discovery & Innovation » Stories of Discovery & Discovery & Innovation » Stories of Discovery & Innovation » 2011 Discovery & Innovation Stories of Discovery & Innovation Brief Science Highlights SBIR/STTR Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 Stories of Discovery & Innovation 2011 Print Text Size: A A A RSS Feeds FeedbackShare Page Microscopic image showing three-dimensional "gated" topological insulator device fabricated from (Bi0.50Sb0.50)2Te3 nanoplates. 12.02.11Stories of Discovery & Innovation The Strange Future of Electronics New materials called "topological insulators" may help us chart a path beyond Moore's Law. Read More » Pamela Peralta-Yahya, Taek Soon Lee, and Mario Ouellet of the DOE Joint BioEnergy Institute team that used microbes to synthesize a bio-based drop-in substitute for diesel fuel.

37

Petascale Direct Numerical Simulations of Turbulent Channel Flow  

NLE Websites -- All DOE Office Websites (Extended Search)

Petascale Petascale Direct Numerical Simulations of Turbulent Channel Flow MyoungKyu Lee mk@ices.utexas.edu Department of Mechanical Engineering University of Texas at Austin ESP Meeting May, 2013 M.K. Lee (Univ of Texas, Austin) Petascale DNS of Turbulent Channel Flow ESP Meeting May, 2013 1 / 30 Contents Project Overview Performance Optimization Early Result Conclusion M.K. Lee (Univ of Texas, Austin) Petascale DNS of Turbulent Channel Flow ESP Meeting May, 2013 2 / 30 Project Overview Project Title ◮ Petascale Direct Numerical Simulations of Turbulent Channel Flow Goal ◮ Expanding our understand of wall-bounded turbulence Personnel ◮ P.I. : Robert Moser ◮ Primary Developer : M.K.Lee ◮ Software Engineering Support : Nicholas Malaya ◮ Catalyst : Ramesh Balakrishnan M.K. Lee (Univ of Texas, Austin) Petascale DNS of Turbulent Channel Flow ESP Meeting May, 2013 3 / 30 Turbulent

38

unknown title  

E-Print Network (OSTI)

Graphene coating makes carbon nanotube aerogels superelastic and resistant to fatigue Kyu Hun Kim, Youngseok Oh and M. F. Islam* Lightweight materials that are both highly compressible and resilient under large cyclic strains can be used in a variety of applications 18. Carbon nanotubes offer a combination of elasticity, mechanical resilience and low density 9, and these properties have been exploited in nanotube-based foams 1014 and aerogels 15,16. However, all nanotube-based foams and aerogels developed so far undergo structural collapse 15 or significant plastic deformation with a reduction in compressive strength 10,11,13,14 when they are subjected to cyclic strain. Here, we show that an inelastic aerogel made of single-walled carbon nanotubes can be transformed into a superelastic material by coating it with between one and five layers of graphene nanoplates. The

unknown authors

2012-01-01T23:59:59.000Z

39

Publications  

NLE Websites -- All DOE Office Websites (Extended Search)

3 results: 3 results: BibTex RIS RTF XML Sort by: Author Title Type [ Year (Desc) ] Filters: Author is Ivan T. Lucas [Clear All Filters] 2012 Lux, Simon F., Ivan T. Lucas, Elad Pollak, Stefano Passerini, Martin Winter, and Robert Kostecki. "The mechanism of HF formation in LiPF6 based organic carbonate electrolytes." Electrochemistry Communications 14, no. 1 (2012): 47-50. 2011 He, Qinggang, Ahmet Kusoglu, Ivan T. Lucas, Kyle Clark, Adam Z. Weber, and Robert Kostecki. "Correlating Humidity-Dependent Ionically Conductive Surface Area with Transport Phenomena in Proton-Exchange Membranes." J. Phys. Chem. B. 115, no. 40 (2011): 11650-11657. 2009 Hardwick, Laurence J., Juliette A. Saint, Ivan T. Lucas, Marca M. Doeff, and Robert Kostecki. "FTIR and Raman Study of LixTiyMn1-y2(y=0,0.11)

40

Scalable DNS code for high Reynolds number channel flow simulation on BG/Q  

NLE Websites -- All DOE Office Websites (Extended Search)

Scalable Scalable DNS code for high Reynolds number channel flow simulation on BG/Q MyoungKyu Lee mk@ices.utexas.edu Department of Mechanical Engineering University of Texas at Austin MiraCon Mar, 2013 M.K. Lee (Univ of Texas, Austin) DNS code for high Re flow on BG/Q MiraCon Mar, 2013 1 / 35 Contents Project Overview Performance Optimization Early Result Conclusion M.K. Lee (Univ of Texas, Austin) DNS code for high Re flow on BG/Q MiraCon Mar, 2013 2 / 35 Project Overview Project Title ◮ Petascale Direct Numerical Simulations of Turbulent Channel Flow Goal ◮ Expand our understand of wall-bounded turbulence Personnel ◮ P.I. : Robert Moser ◮ Primary Developer : M.K.Lee ◮ Software Engineering Support : Nicholas Malaya ◮ Catalyst : Ramesh Balakrishnan M.K. Lee (Univ of Texas, Austin) DNS code for high Re flow on BG/Q MiraCon Mar, 2013 3 / 35 Overlap Region Connection between near-wall

Note: This page contains sample records for the topic "ahmet kyu taek" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Role of Chemical-Mechanical Energies in Understanding Structure and  

NLE Websites -- All DOE Office Websites (Extended Search)

Chemical-Mechanical Energies in Understanding Structure and Chemical-Mechanical Energies in Understanding Structure and Properties of Aged and Degraded Membranes Title Role of Chemical-Mechanical Energies in Understanding Structure and Properties of Aged and Degraded Membranes Publication Type Journal Article Year of Publication 2013 Authors Kusoglu, Ahmet, and Adam Z. Weber Journal ECS Transactions Volume 50 Issue 2 Pagination 961 - 965 Date Published 03/2013 ISSN 1938-6737 Abstract Polymer fuel-cell membranes are the core component of fuel-cells having multiple functionalities including water absorption, ionic conductivity, and mechanical support. All these functionalities are correlated via the membrane nanostructure and chemical properties. This study aims at investigating the changes in the structure-uptake relationship due to membrane degradation and ageing. We show that, after in-situ chemical degradation (i.e., OCV holds), the membrane's water uptake and water-domain spacing both decrease compared to a fresh membrane. In addition, the MEA manufacturing process is also found to alter the membrane's nanostructure and uptake behavior, which suggests that changes in the properties of bare membranes during processing and cell operation must be accounted for when analyzing and modeling cell performance. The experimental data is evaluated using an energy-balance approach to examine the correlations among domain spacing, water content, and mechanical properties for degraded membranes.

42

Effect of compression on PFSA-ionomer morphology and predicted conductivity  

NLE Websites -- All DOE Office Websites (Extended Search)

Effect of compression on PFSA-ionomer morphology and predicted conductivity Effect of compression on PFSA-ionomer morphology and predicted conductivity changes Title Effect of compression on PFSA-ionomer morphology and predicted conductivity changes Publication Type Journal Article Year of Publication 2012 Authors Kusoglu, Ahmet, Alexander Hexemer, Ruichun Jiang, Craig S. Gittleman, and Adam Z. Weber Journal Journal of Membrane Science Volume 421-422 Pagination 283 - 291 Date Published 12/2012 ISSN 03767388 Keywords Compression, conductivity, Domain spacing, nafion, SAXS Abstract Ion-conductive membranes used in energy devices are always under compression to minimize a device's contact resistance. In this paper, the conductivity and nanostructure of Nafion membrane, a commonly used ionomer in many electrochemical energy applications, are investigated under compression. Hydrophilic-domain spacing as a function pressure is determined both in the plane (face-on imaging) and thickness (edge-on imaging) directions using small-angle X-ray scattering (SAXS). SAXS results suggest a similar nanostructure in all directions indicating lack of a strong anisotropy when not under compression. However, compressing the membrane induces structural anisotropy where domain spacing gets smaller in the compression (thickness) direction while it elongates in the plane of the membrane. From the domain spacing and water content under compression, the change in conductivity is calculated as a function of pressure and compared with measured data. The findings of this work provide insight into the effect of compression on the three-dimensional morphology of a PFSA membrane and its conductivity, issues that have not been previously explored and are critical to the understanding of ion-conductive membranes.