PEM Electrolyzer

Using graphitized carbon panels as current collectors for polymer electrolyte membrane electrolysis

Best cost to performance current collector

Current Collectors for PEM Electrolyzers

Using Carbon Paper & Panels as Cathode-side Current Collectors

Spectracarb GDL 2050A-6060 Porous Graphite Engineered Panels

Spectracarb™ GDL 2050A-6060 Porous Graphitized Carbon Panels are optimum for use as Cathode (Hydrogen Side) Current Collectors in PEM Electrolyzers. Unlike the standard thin/low density Gas Diffusion Layers (GDL) that are intended mainly for PEM and PAFC fuel cells, the Spectracarb Porous Graphite Engineered Panel Family has been specifically engineered for the special requirements of PEM electrolyzers. Features include thicker structures of from 1.5 to over 4 millimeters, and densities up to 0.95 g/cm3. These panels also have controlled compressibility to support the external forces from the assembly. In additional to several standard grades, these engineered panels can be made on a laboratory, prototype or production scale to meet specific customer requirements.

Graphitized Carbon Paper & Panels for PEM Electrolyzers

Slide 1

Porous Graphite Materials Development for Specific Electrochemical Applications Presented By: Robert E. Evans Hannover Messe April 13-17, 2015

Slide 2

Engineered Fibers Technology

Engineered Fibers Technology Established 1998 Founded In 1998 - Founding Members Each With Over 30 Years Experience - Fibers/Composites High Technology Fibers Materials /Services Located in Shelton, CT (1950 Sq. Meters) - Fiber Processing - Materials Development Lab - Spectracarb Development

Slide 4

High Technology Fibers, Materials, Services
Wide Range of Technical Engineering Applications for Spectracarb

  • PEM Electrolyzers
  • Fuel Cells
  • Heat Management
  • Redox Flow Batteries
  • Gas Diffusion Layers
  • Gas Diffusion Media
  • Porous Graphitized Carbon Sheets
  • Fuel Cell Powered City Buses

Slide 3

Spectracarb Porous Graphite GDL Applications All images copyright of respective trademark holders. Spectracarb_Applications Spectracarb GDL Background .From 1991-2005, Spectracorp. Ltd was . Leading producer of GDL products for commercial application- SpectracarbTM GDL . Leader in development of new GDL materials .DOE Contracts .Automotive / Industrial Sponsorship Spectracarb GDL Background .Since 2005 EFT has grown Spectracarb Porous Graphite Materials through . Engineered Materials Research . Wet-Laid Paper Development . Specialty Short-Cut Fiber Investigations .Partnership with Caplinq Europe BV Since 2013 .Technology Focus is Customer Driven GDL Development Wet-Laid Resin Bonded Paper / Panels Nonwoven Needle punched Felts / Woven Fabrics Production of Porous GDL Materials Wet-Laid Porous Graphite Paper –General Processing Scheme PAN Filament Carbon Filament Carbon Fiber Slurry Bonded Graphite Fiber Paper / Panel Other Components Resin Impregnation Specific Porous Graphite Paper / Panel Wide Range of Carbon Fibers Available from producers Stabilization / Graphitization 900- 3000oC Stabilization, carbonization Precision Cutting Molding /Resin Curing Paper Formation Optional Wet-proofing, MPL coating, sintering Advantages of Papermaking Approach for Specialized GDL Products . Versatility - Wide Range of Fibers / Particle Modifiers/Binders Can be Included in Papermaking . Thickness / Density /Porosity Control . High Density /Thick Panels with High Compressive Compliance / Low Flow Channel Intrusion . Preparation on Laboratory / Pilot / Production Scale . Small Production Runs Possible EFT / Spectracarb GDL Macroporous Graphite Materials .Very High Conductivity Porous Graphite Papers / Panels .High Strength and Durability .Good Air Permeability .Moisture Transport / Water Management .Lab-Scale Prototype Development to Commercial Scale Manufacturing .Produced in US / Caplinq European Agent Paper is Less Compressive than Felts and Woven Construction Spectracarb GDL Technology Focus .Provide lower cost products that are interchangeable with other existing standard grades .Development /Commercial Production of GDL products meeting specific customer requirements / electrochemical applications .Creation of “Next Generation” GDL products .Joint Development /Engineering Programs .Independent /Contract Research Spectracarb GDL Technology Focus . Provide lower cost products that are interchangeable with other existing standard grades .Development /Commercial Production of GDL products meeting specific customer requirements / electrochemical applications .Creation of “Next Generation” GDL products .Joint Development /Engineering Programs .Independent /Contract Research . China City Bus Program –Fuel Cell Technology . Shanghai Shen-Li Fuel Cell Production . 2008 Olympics /2010 World Expo . Spectracarb 2050A-0850 GDL Lowest Cost Selection . Several Thousand Sheets, 0.2 mm / 40 x 40 cm news_en_clip_image002 Spectracarb 2050A-0850 Properties Measurement Units Spectracarb 2050A-0850 Thickness mm 0.20 Basis Weight g/m2 88 Geometric Density g/cm3 0.44 Mean Pore Size micron 27 Air Permeability, through-plane cfm/ft2 35 Electrical Resistivity through-plane in-plane mW·cm2 mW·cm 18 5.4 Thermal Conductivity through-plane (@ 25°C) through-plane (@ 100°C) in-plane (@ 25°C) in-plane (@ 100°C) W/m·K 3.4 3.6 20.7 24.2 Tensile Strength MD XMD MPa 4.2 2.6 Flexural Strength MPa 37 Flexural Stiffness GPa 9.5 Compressive Strength MPa 2.1 Spectracarb GDL Technology Focus .Provide lower cost products that are interchangeable with other existing standard grades .Development /Commercial Production of GDL products meeting specific customer requirements / electrochemical applications .Creation of “Next Generation” GDL products .Joint Development /Engineering Programs .Independent /Contract ResearchPorous Graphite Papers/Panels Used in Range of Devices .PEM / PA Fuel Cells .Redox Flow Batteries .PEM Electrolyzers .Humidifiers .Electrochemical Reactors It Should Not Be Expected That One Material - Or Family of Materials - Will be Optimum for All Applications PEM Fuel Cell Gas Diffusion Layers (GDL) Wet-Laid GDL Paper General Processing Schemes Papers PAN Filament Carbon Filament Carbon Fiber Slurry Bonded Graphite Fiber Paper / Panel Other Components Resin Impregnation Specific Porous Graphite Paper / Panel Wide Range of Carbon Fibers Available from producers Stabilization / Graphitization 900- 3000oC Stabilization, carbonization Precision Cutting Molding /Resin Curing Paper Formation Optional Wet-proofing, MPL coating, sintering HandsheetMold1 tgp_large Lower Cost (Second Generation) GDL Investigations for Automotive Applications- GM Sponsored Graphs from MS&T 2009/2011 Conferences –Nicotera et al Engineered GDL for Improved Water Management Anode GDL (Higher Diffusion Resistance) Cathode GDL (Standard Construction) US Patent 8518596 B1 “Low cost fuel cell diffusion layer configured for optimized anode water management” – GM 2013 Vanadium Redox Battery Porous Electrodes Redox Flow Batteries .Redox flow batteries (RFBs) are “flow-through” electrochemical reactors, analogous in many respects to fuel cells .Suitable for large scale, stationary energy storage applications (grid storage) .Typically aqueous-based systems: the all vanadium RFB is currently the state-of-the-art (Ecell ~ 1.2-1.6 V) . RFBs feature long cycle life (> 10,000 cycles), and high cell efficiencies . RFBs have low energy densities compared to other secondary battery systems (~ 15-30 Wh/L) . Many demonstration units exist world wide; kWh-MWh capabilities . Key feature of RFBs: power and energy density can be mutually exclusive (i.e. decoupled), unlike other battery technologies; use larger tanks for higher kWh, and increase the size or number of cells for higher kW university-of-kentucky-logo.jpg Carbon Electrode Development . Commercial and custom-made carbon papers and felts are being examined for improved electrocatalytic activity . Various thermal, chemical, and electrochemical treatments can be used to modify the electrocatalytic activity of carbon electrodes . Unmodified Spectracarb 1550 carbon paper shows improved electrochemical reversibility and catalytic activity when compared to common commercial grade carbon paper used in various RFB systems RFB performance metrics: CE = td/tc x 100% VE = Vd/Vc x 100% EE = CE x VE university-of-kentucky-logo.jpg Vanadium Redox Battery Porous Electrodes . Literature Reference Shows Porous Carbon Papers Have Better Performance than Felts (Q.H. Liu – J. of Electrochemical Society -2012) . Spectracarb 1550 Shows Better Performance than Other Commercial Paper (UKy) . Spectracarb 1550 Being Used as Baseline For Continuing Development / Customer Specific Targets –EFT Program . Reference Also Shows Effect of Thickness (Number of Stacked Sheets of Paper): Suggests Thicker Panels May Increase Performance Spectracarb 2050A-1550 Properties Measurement Units Spectracarb 2050A-1550 Sheet size mm 400 x 400 Thickness mm 0.350 Basis Weight g/m2 175 Geometric Density g/cm3 0.50 Air Permeability, through-plane cfm/ft2 35 Electrical Resistivity through-plane (@ 200 kPa) in-plane mW·cm2 mW·cm 15 5.4 Thermal Conductivity through-plane (@ 25°C) through-plane (@ 100°C) in-plane (@ 25°C) in-plane (@ 100°C) W/m·K 3.4 3.6 20.7 24.2 Flexural Strength MPa 40 Porosity % 78 PEM Electrolyzer Cathode Current Collector Laboratory Electrolyzer with Spectracarb Cathode Current Collectors- Curiosity SINTEF Spectracarb Panels for Electrolyzer Cathode Current Collectors . Lower Cost Alternative to Ti Mesh . Thicker Plates (Up to 5mm) . Higher Density (up to 1g/cm3) . Higher Bending Stiffness vs Stacking of Thin Papers . Function as Elastic Springs in Compression (30%) . Machinability . Hybrid Constructions Possible Spectracarb GDL Panels For Electrolyzer Cathode Applications Properties- Spectracarb Electrolyzer Panel Spectracarb Electralyzer Panels-Repeated Loading Stress : Repeated Compression - 20% Strain Resistivity: Repeated Compression - 20 % Strain Other Specific Designs for Electrochemical Applications . Thin GDL with same requirements as Fuel Cell Except Conductivity / Graphitization Not Necessary . Paper Based on Glass / Ceramic Fiber- High Purity Resin Binder . US Patent 8974977 “Wetside Paper for Fuel Cell Humidifier” GM 2015 Humidifiers for Fuel Cells Electrolyzers for Chemical Electrolysis . Thicker Electrode Panels Similar to Water Electrolysis with High Flow (HF) –Larger Average Pore Size / Higher Porosity / Low Pressure Drop . US Patent 7341654 “Mediated Hydrohalic Electrolyzers” (2008) Spectracarb Technology Focus . Provide lower cost products that are interchangeable with other existing standard grades .Development /Commercial Production of GDL products meeting specific customer requirements / electrochemical applications .Creation of “Next Generation” GDL products . Joint Development /Engineering Programs . Independent /Contract Research Laboratory Scale GDL Development / Preparation (One Example) .EFT or Customer Formulation Development .Short fiber cutting of carbon and other fibers to lengths of 0.25 mm to 25 mm . .Production of slurry molded carbon fiber paper handsheets, up to 30 cm x 30 cm, in weights of from 30-300 g/m2 using different fibers, binders and resins. .Lay-Up, Molding and Curing of GDL papers / panels to specific thicknesses and densities. .Graphitization of Lab sized GDL (20x 20 cm standard, but facilities available for 30 x 30 cm ) at temperatures > 2000 oC .Mechanical /Physical / Electrical Characterization .Submission to Customer for Lab Scale Stack Evaluation Summary –Spectracarb Porous Graphite Papers / Panels .Spectracorp / Engineered Fibers Technology has been Providing SpectracarbTM Porous Graphite Papers and Panels on Both a Developmental and Commercial Basis Since 1991. .Customer Driven Development and Production to Meet Customer Needs. Small Quantity Production. .Wet- Laid Resin Bonded / Graphitized Papers Provide High Level of Versatility to Meet Specific Applications .PEM / PA Fuel Cells .Redox Flow Batteries .PEM Electrolyzers .Humidifiers .Electrochemical Reactors .Commercial Scale – Up to 55 x 55 cm Graphitized Papers /Panels. Largest Range of Porous Graphite Papers /Panels of All Suppliers .Laboratory /prototype Scale- Up to 30 cm x 30 cm, in weights of from 20-300 g/m2 using different fibers, binders, resins and other components. .Caplinq Europe BV Technical / Sales Customer Service Agent Available to Assist with European Support THANK YOU! Engineered Fibers Technology Please Visit Us at Stand C40/4 to Discuss Your Specific GDL Requirements www.Spectracarb.com inline_logo.png Spectracarb Graphitized Carbon Paper as Current Collectors for PEM Electrolyser Applications CHRISTOPHER PERABO - HANNOVER MESSE TECHNICAL FORUM – 28 APRIL 2016 inline_logo.png CAPLINQ Europe BV Manufacturer | Distributor | Partner 1.EFT and CAPLINQ Intro USA and Europe Partnership 2.PEM Electrolyzer Market Markets and Applications 3.Spectracarb Production Process The logic of the papermaking process 4.Cost Drivers How next generations will bring down the cost PRESENTATION OUTLINE inline_logo.png -European presence without requiring a European entity -We give foreign companies local storefront presence -No commissions / distributor fees -We are engineers and technical representatives -We travel through Europe, the Middle East and Africa -We meet with designers and engineers, not just purchasers TECHNICAL REPRESENTATIVE CAPLINQ GETS WHAT MARKET PARTNER MEANS Not a one-stop shop, but a modular service provider -We build brand and product awareness: online and offline -We design technical datasheets, selector guides and brochures ORDER FULFILLMENT MARKETING STRATEGISTS MARKET PARTNER inline_logo.png KEY FACTS: Founded In 1998 Founding Members Each With Over 30 Years Experience Fibers/Composites High Technology Fibers Materials /Services Located in Shelton, CT 1950m2 (~21,000 sq. ft) facility Fiber Processing Materials Development Lab Spectracarb Development ENGINEERED FIBERS TECHNOLOGY Established 1998 inline_logo.png SPECTRACARB GDL BACKGROUND Timeline 1991 - 2016 Spectracarb early days – 1991 to 2005 Leading producer of GDL products for commercial applications Leader in development of new GDL materials •DOE Contracts •Automotive / Industrial Sponsorship Spectracarb 2005 - 2012 Acquired by EFT who has grown Spectracarb through: • Engineered Materials Research • Wet-Laid Paper Development • Specialty Short-Cut Fiber Investigations Spectracarb 2013 - 2016 Partnership with Caplinq Europe BV Since 2013 •Attended Hannover Messe every year since 2013 •Technology Focus is customer-led GDL Development inline_logo.png Hydrogen Fuel Cell Toyota Fuel Cell FUEL CELLS VS ELECTROLYZER Opposite sides of the same coin Polymer electrolyte membrane (PEM) Electrolyzer FUEL CELL Hydrogen IN Electricity OUT ELECTROLYZER Electricity IN Hydrogen OUT inline_logo.png http://eandt.theiet.org/magazine/2014/04/images/640_smart-grid.jpg THE MARKET IS CALLING FOR ELECTROLYZERS There are at least four clear markets that have emerged http://www.all-water.org/H2O_Images/640px-Water_molecule_3D.svg.png https://qph.is.quoracdn.net/main-qimg-55d35b4409ef06ce96457789a37a1b4b?convert_to_webp=true https://qph.is.quoracdn.net/main-qimg-55d35b4409ef06ce96457789a37a1b4b?convert_to_webp=true https://qph.is.quoracdn.net/main-qimg-55d35b4409ef06ce96457789a37a1b4b?convert_to_webp=true https://qph.is.quoracdn.net/main-qimg-55d35b4409ef06ce96457789a37a1b4b?convert_to_webp=true http://www.all-water.org/H2O_Images/640px-Water_molecule_3D.svg.png + + CO2+ 4H2 CH4 + 2H2O Biogas plants Electrolyzers have been used to convert CO2 from biogas plants into methane and water Power Grid Stabilization Storage of renewable energy for grid stabilization inline_logo.png Remote Hydrogen Production Electrolyzers are used to produce hydrogen for industrial uses in areas that are remote or difficult to access Hydrogen Fuel Electrolyzers are used to resupply fuel cells for automotive and light duty vehicles https://remote-sms-call-gps-tracker.com/img/icon.png inline_logo.png ELECTROLYZERS FOR GRID STABILIZATION USE AMMONIA INSTEAD OF METHANE TU Delft and NUON are partnering to use the H2 created by electrolyzers to create ammonia. inline_logo.png https://qph.is.quoracdn.net/main-qimg-55d35b4409ef06ce96457789a37a1b4b?convert_to_webp=true + N2+ 3H2 2NH3 By using ammonia (NH3) instead of methane (CH4), energy is generated without freeing CO2 inline_logo.png WHERE IN THE WORLD? Electrolyzers for various purposes around the world https://upload.wikimedia.org/wikipedia/commons/thumb/a/a0/World_map_with_points.svg/2000px-World_map_with_points.svg.png United States California is leading the way in developing the hydrogen station infrastructure, but generally, the USA is slow in addressing hydrogen storage. Germany In Germany, H2 can be fed back into the natural gas (CH4) grid which can accept a 5% surplus of H2 Netherlands In Netherlands, N2 is combined with H2 to create ammonia (NH3) which is stored as a liquid and reused Brazil, India and Africa Today, PEM Electrolyzers are still more expensive that H2 suppliers, but as PEM costs drop PEMs more gain in market share. Also in some cases, the areas are too remote that PEM Electrolyzers are the best viable option. inline_logo.png WHERE IS SPECTRACARB USED? Different materials for different applications •Shanghai Shen-Li Fuel Cell Production •2008 Olympics/2010 World Expo China City Bus Program Spectracarb 2050A 6060 OGP.photo2.jpg Vanadium Redox Battery FUEL CELL TECHNOLOGY Spectracarb 2225-900 ACF PEM ELECTROLYZER Current Collector ULTRA CAPACITOR Spectracarb 2050A 15590 / 7090 Porous Electrodes Spectracarb 2050A 0850 inline_logo.png MATERIAL COMPARISON FOR CURRENT COLLECTOR Bipolar Plate (BiP) Current Collector Iridium Oxide (IrO2) Membrane Electrode Assembly (MEA) Platinum (Pt) Membrane Spectracarb GDL 2050A-12580 Cathode inline_logo.png MATERIAL COMPARISON FOR CURRENT COLLECTOR Sintered titanium vs graphitized carbon panels POROUS CURRENT COLLECTOR MATERIALS Material Properties Spectracarb 2050A-6060 Sintered Titanium Thickness Thickness range from 125micron to 4mm. Cost has non-linear relationship. Any thickness is possible, but cost has a linear relationship to thickness Oxidation on Cathode (H2) side No such effect with the Spectracarb GDL Presents longer-term reliability as the compressed H2 makes the sintered titanium malleable Compressibility Can be compressed significantly. A 3mm thick sheet can compress to 2mm under pressures of 6-8MPa Not compressible (rigid) at electrolyzer pressures Compression Set No compression set. Near perfect hysteris after pressure is removed. N/A – Not compressible Pore Size Random distribution, average pore size is 20 micron 20 – 100 microns Porosity 70 – 75% 30 – 50% Resistance Values Slightly lower resistance values than with sintered titanium. Higher hear treatment decreases resistance. Slightly higher resistance values obtained than with carbon panels Cost Considerable price advantage of the carbon paper Considerably more expensive. Twice as expensive in low volumes. Microporous Layer Can be manufactured directly on the carbon paper Requires a standalone MPL Under Pressure Carbon paper tends to become brittle under higher pressure No increased brittleness under pressure Electrical Conductivity Requires at least 100 S/cm, the higher the better inline_logo.png SPECTRACARB PRODUCTION Spectracarb production Capability Production Capacity* > 50K sheets / year (40 x 40 cm / 50 x 50 cm) *without any manufacturing changes) Ongoing Production Capacity >100 K Sheets/year *without additional Capital Larger Size Sheets 55 x 55 mm -70 x 70 mm are Possible with Additional Equipment / Higher Graphitization Temperatures Possible inline_logo.png D:\ESEM TDV images\19-1 Dn side FOV 2 BSE_001.tif EFT / SPECTRACARB GDL FOR FUEL CELL ELECTRODES KEY APPLICATION REQUIREMENTS: Very High Conductivity Porous Graphite Papers & Panels High Strength and Durability Good Air Permeability Excellent Moisture Transport / Water Management Lab-Scale Prototype Development to Commercial Scale Manufacturing Produced in USA / CAPLINQ European Agent inline_logo.png Custom Carbon Panels •Specific Porosity •Specific Density •Tight tolerance on both size and thickness Stabilization / Graphitization Furnace temperatures up to 900°C - 3000oC Bonded Graphite Fiber Paper/Panel WET-LAID POROUS GRAPHITE PAPER PROCESS Basic Process Scheme Carbon Filament Precision Cutting Carbon Fiber Slurry Resin Impregnation Molding / Resin Curing Once injected, resin is cured (hardened) Paper Formation Optional Wet- proofing, MPL coating, sintering Other Components PAN Filament Stabilization, carbonization Carbon Fibers Wide range of carbon fibers available inline_logo.png ADVANTAGES OF PAPERMAKING APPROACH FOR SPECIALIZED GDL PRODUCTS http://jgvision.com/JGvision/Research_files/IconDensity.png Versatility Wide range of fibers, particle modifiers & binders can be used in papermaking process. Small Scale Papermaking process makes small production runs possible. Lab Scale Preparation is scalable from lab batch to pilot batch to production scale. Tolerance Process allows wider control over the thickness, density and porosity. High Density High density and thick panels with high compressive compliance are possible. inline_logo.png ENGINEERED FIBERS TECHNOLOGY GDL PRODUCTS All Spectracarb™ grades of gas diffusion layer ENGINEERED FIBERS TECHNOLOGY GAS DIFFUSION LAYER PRODUCTS – ALL SPECTRACARB GRADES Gas Diffusion Layer (GDL) Spectracarb Grade Type Thickness µm (mils) Density (g/cm³) Basic Weight (g/m²) Air Permeability (cfm/ft2) Through Plane Resistance (mOcm²) Tensile Strength (N/cm) Flexural Strength (MPa) Flexural Stiffness (GPa) Porosity Mean Pore Size (µm) Thermal Conductivity (W/m-K) TP (IP)1 PTFE Treated MPL 2050A-0550 Paper 130 (5) 0.5 - 35 - - - > 70% No No 2050A-0850 Paper 203 (8) 0.44 88 35 18 4.2 MD & 2.6 XMD 37 95 >70% 3.4 (20.7) No No 2050A-1050 Paper 250 (10) 0.5 - 35 - - - >70% No No 2050A-1240 Paper 310 (12) 0.9 - 35 - - - >70% No No 2050A-1535 Paper 380 (15) 0.35 - 35 - - - >70% No No 2050A-1550 Paper 380 (15) 0.5 175 35 15 - 40 78% 3.4 (20.7) No No 2050A-1732 Paper 430 (17) 0.32 - 35 - - - >70% No No 2050A-2050 Paper 500 (20) 0.5 - 35 - - - >70% No No 2050A-6060 Paper 1524 (60) 0.6 - 35 - - - >70% No No 2050A-7090 Paper 1778 (70) 0.9 - 35 - - - >70% No No 2050A-135552 Paper 3429 (135) 0.55 - 35 - - - >60% No No 2050A-150852 Paper 3810 (150) 0.85 - 35 - - - >60% No No 2225-900 ACF Fabric 500 - 135 - - - - - No No 1 TP AND IP STAND FOR THROUGH PLANE AND INPLANE RESPECTIVELY. DATA GIVEN @ 25C 2 SUITABLE FOR CHANNELED FLOW FIELD APPLICATIONS. MACHINES VERSIONS CAN BE SUPPLIED. » TYPICAL DIMENSIONS ARE: 380 X 380MM, 400 X 400MM AND 500 X 500MM » CUSTOM GRADES AND SIZES (UP TO 1 SQUARE METER) CAN BE FABRICATED TO MEET CUSTOMER SPECIFICATIONS inline_logo.png SPECTRACARB AS ELECTROLYZER CURRENT COLLECTOR Only Spectracarb GDL Panels can be both thick and dense Spectracarb Electrolyzer Cathode GDL Panels Spectracarb Electrolyzer Cathode GDL Panels 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Density, g/cc 4000 3500 3000 2500 2000 1500 1000 500 0 Thickness, microns Spectracarb Electrolyzer Cathode GDL Panels Spectracarb Carbon Panels can be produced as thin as 130µm (5 mils) and as thick as 3810 130µm (150 mils) THICKNESS Spectracarb Carbon Panels have density as low as 0.32 g/cm3 and as thick as high as 0.95g/cm3 DENSITY ONLY SPECTRACARB GDL CAN BE BE BOTH THICK AND DENSE inline_logo.png PROPERTIES- SPECTRACARB ELECTROLYZER PANEL Spectracarb is an elastic material 0 200 400 600 800 1000 1200 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Stress, PSI Percent Strain 0 10 20 30 40 50 60 70 80 90 100 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Resistivity, mOhm-cm Percent Strain 0.0 5.0 10.0 15.0 20.0 25.0 0 200 400 600 800 1000 Strain, % Strain (%) vs. Stress over compressive loading Percent Strain 1 Percent Strain 2 0 20 40 60 80 100 120 140 160 0 200 400 600 800 1000 Resistivity Resistivity (mOhm-cm) vs Stress (psi) Resistivity, mOhm-cm, 1st Loading Resistivity, mOhm-cm, 2nd Loading Stress: Repeated Stress <20% Strain Resistivity: Repeated Stress 2000°C. •Furnace runs are ~50% of cost Low volumes are expensive! Whether the furnace runs 1 part or 10,000 parts, the furnace cost is the same. There is a linear relationship between cost and number of units produced. •Panels are molded in sheets •Circles mean waste material •Panel optimization is key •Materials are ~25% of BOM EFT’s efforts focus on optimizing furnace production runs. 50% 25% 25% EFT is exploring cheaper methods EFT is exploring optimal sizes inline_logo.png PLEASE VISIT US IN HALL 27, STAND D-35 inline_logo.png THANK YOU! Please get in touch with us to discuss your specific application Engineered Fibers Technology, LLC Serving USA, Canada, Mexico & South America 88 Long Cross Road Shelton, CT 06484 USA Phone: +1 (203) 922 1810 Fax: +1 (203) 922 1814 Amsterdam, Netherlands Office Serving Europe, Middle East, Asia & Africa Provincialeweg 1 1561KK Krommenie The Netherlands Phone: +31 (20) 893 2224 Fax: +31 (84) 746 3497 inline_logo.png PLEASE VISIT US IN HALL 27, STAND D-35

  • Lower Cost compared to Titanium Mesh / Sintered Ti for Cathode (H2 Side) Electrode Thicker Plates (Up to 5mm)
  • Higher Density (up to 1 g/cc)
  • Higher Bending Stiffness vs Stacking of Thin Papers
  • High Elastic Spring Compression Constant (up to 30% compression with full recovery)
  • Good Machinability
  • Hybrid Constructions Possible
  • Long Term Performance / Corrosion Resistance
  • Demonstrated: Commercial / Military Applications
  • Laboratory/ Prototype and Commercial Scale

Spectracarb Family of Engineered Panels for Electrolyzer Applications

Graphitized Carbon Panels and Sheets

Figure 1. Various gas diffusion options plotted thickness in microns against density in g/cc. Spectracarb electrolyzer cathode carbon paper in the top right offer the industry's thickest panels with density ranges from 0.5g/cc to 1 g/cc. Carbon Papers, GDL felts and GDL cloths are all very thin - all of them are less than 500 microns thick and have densities between 0.2 g/cc and 0.6 g/cc.
Figure 2. Spectracarb carbon paper and carbon panels. The Spectracarb family of panels are specially constructed to meet specific customer specifications. Also, Spectracarb panels are available in several standard grades from 1.5 mm to 3.5 mm thickness and up to 0.95 g/cm3. Sizes up to 55 x 55 cm panels or machined discs can be supplied. We have succesfully been able to water-cut disks to a very tighht tolerance.

Spectracarb 2050A-12580 (Customer Specific Product)

Strain vs. Stress of carbon panel over compressive loading

Figure 3. Notice that the strain % is the same after repeated stress encounters, so there is no hysteris.

Resistivity vs Stress of Graphitized Carbon Sheets

Figure 4. The resitivity of the carbon graphitized panels in milliohm-cm vs stress in psi. Notice the Spectracarb resistivity is the same after the initial loading as after the second loading.

Current Collector Stress: Repeated Stress <20% Strain

Figure 5. Whether the stress on the carbon paper is 500 psi or the stress on the carbon paper is 1000 psi, the strain is less than 20%.

Current Collector Resistivity: Repeated Stress <20% Strain

Figure 6. After repeated stress the resistivity in mohm-cm is consistent and with the same less than 20% strain.
Spectracarb GDL 2050A-6060
Property Units Value
Size mm 400 x 400
Thickness mm 1.5
Basis Weight g/m2 88
Geometric Density g/cm3 0.6
Average Pore Size microns 20
Electrical Resistivity
 through-plane  in-plane

mohm·cm2
mohm·cm

18
5.4
Thermal Conductivity
through-plane (@ 25°C)
through-plane (@ 100°C)
in-plane (@ 25°C)
in-plane (@ 100°C)


W/m·K

3.4
3.6
20.7
24.4
Tensile Strength
MD
XMD

MPa

4.2
2.6
Flexural Strength MPa 37
Flexural Stiffness GPa 9.5
Compressive Strength MPa 2.1

Applications of Spectracarb Carbon Panels

Figure 7. Clockwise from left: PEM Electrolyzers, PEM Electrolyzer stack, Electrolyzers for military and self-containing applications (in this case, the O2 is produced to provide breathable air), China Bus program used Spectracarb carbon paper for fuel cells.

You can go directly to the Spectracarb™ 2050A-6060 Porous Graphitized Carbon Panels page or you can visit our Graphitized Carbon Paper and Cabon Panel overview page for more information. You can also compare graphitized carbon paper and carbon panels using this tool or contact us for more details on carbon paper, carbon panels or any of our other products.

View our video on Spectracarb porous graphite current collectors for PEM electrolyzer application.