Programme Review Day Brussels, 28 & 29 November. Premium Act

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1 /1 PREdictive Modelling for Innovative Unit Management and ACcelerated Testing procedures of PEFC (256776) Sylvie Escribano CEA Duration: from 3/211 to 2/214 Total budget: FCH contribution:

2 /1 1. project & partnership description IRD Improvement of stationary PEFC systems durability (4h required!) A reliable method to predict system lifetime, benchmark components and improve operating strategies WP2 Experiments under real operating conditions CEA WP6 - Dissemination DLR WP1 - Specifications WP3 Quantification of components degradation CEA IRD WP4 Predictive Modelling CEA POLIMI WP5 Lifetime prediction methodology WP7 - Management

3 /2 1. Project objectives & Approach Expected achievements Operating strategies, enhancing lifetime of given MEAs in given stack and system Design of a lifetime prediction methodology based on coupled modelling and composite accelerated tests experiments (ranking of selected MEAs in real conditions and then following accelerated tests) Technical aspects Two fuel cell stack technologies for stationary power applications: DMFC and H2 reformate PEMFC CHP systems Experimental investigation Tools to quantify & correlate performance and components degradation to operating conditions Multi-physics modelling Tools to combine degradation phenomena and analyse their global impact on durability WP2 Experiments under real operating conditions (systems, stacks & single cell real ageing tests) WP1 Specifications (from systems) WP3 Quantification of components degradation (Ex-situ characterizations, locally resolved analysis) WP4 Predictive Modelling mechanistic model + MEA & cell model WP5 Lifetime prediction methodology (SC specific tests: coupling, validation, Acct)

4 /2 1. Technical Accomplishments and Progress Ageing studies DMFC systems IRD Field tests: IRD 1/2-1 KW DC ICI H2 65 % CO2 22 % CO 5 ppm CH4 3 % N2 1 % PEMFC systems Soprano 4 Ballard Mark9SSL (11 cells) I 4mA/cm² 18h Average cell degradation rate ~ 4A conditions for DMFC SC tests Aged DMFC MEAs for analyses fuel composition effect (CO, CO 2, Air bleed) 6h 65mA/cm² Operating condition tests according to CHP power profiles Conditions and protocols for PEMFC single cells and stack tests ( aged PEMFC MEAs for analyses) t

5 U [V] / HFR [W/cm 2 ]! /2 1. Technical Accomplishments and Progress Ageing studies DMFC stack and single cells DMFC MEA DURABILITY TEST [1] T cell = 75 C, l Air = 3., l CH3OH = 4., 1. M CH 3 OH Voltage OCV HFR y = -.118x R 2 = IRD & POLIMI Methodologies to analyse temporary and permanent degradation for stationary or cycling operation.25. High Frequency Resistance (HFR): y = 1.E-.7 * X ,5 5, 7,5 1, A/cm 2 Cell voltage degradation for DMFC stack long term operation (< 12µV/h) Testing of refresh procedures Operating strategies to reduce temporary or overall degradation rate Further interpretation of refresh procedures vs. temporary and permanent degradation Development and application of other protocols and operating strategies

6 /2 1. Technical Accomplishments and Progress U(V) I(A) Ageing studies LT PEM 5-layer Reference MEAs Description Product ID Catalyst loading Anode GDL Sigracet 35DC Anode Catalyst Hispec 1.3 mg PtRu/cm 2 Membrane Nafion N212CS XL Cathode Catalyst Hispec 91.5 mg Pt/cm 2 Cathode GDL Sigracet 35DC CEA DMFC 5-layer Reference MEAs Description Product ID Catalyst loading Anode GDL Sigracet 35DC H2 Anode Catalyst Cabot Dynalyst 62RKR4 inlet 1.8 mg PtRu/cm 2 Membrane Air Nafion N115CS Cathode Catalyst inlet Cabot Dynalyst 65KR2 1.2 mg Pt/cm 2 Cathode GDL Sigracet 35DC H2: 79% CO 2 : 2% CH 4 : 1,3% CO: 26 ppm Stfuel 1,2 Stair 2 P = 1,2 bar RHfuel 1% RHair 5% or 4% Tfuelcell : 75 C PEMFC stack and single cells Single Cell - 89µV/h SC voltage / load cycles high performance degradation rate Stack - Pure H 2 1,2 1A reformate 1h 1A H2 1h 75 C 1/4%RH 1.2b H2 pur - Im (Z) BoT H2 BoT reformate 1A H2 BoT,9 75 C 1/4%RH 1.2b H2 pur 1h-2,15 75 C 1/4%RH 1.2b H2 reformé,8 EoT H2 EoT reformate,1 75 C 1/4%RH 1.2b H2 reformé 1h 1 cells voltages during i min /i max load cycles Electrochemical diagnostics cell by cell,7,6,5,4,3, i(ma/cm²) but low permanent degradation of components properties (EoT diagnostics),5,1,2,3,4,5,6,8,6,4,2 -,2 -,4 -,6 -,8-1,2,4,6,8 Interpretation to be completed [ex-situ local observations & measurements] - Development and application of other protocols (incl. coupling higher [CO] & cycles) and operating strategies U(V) CV CAT BoT CV CAT EoT Re (Z)

7 /2 1. Technical Accomplishments and Progress Characterizations for degradation investigation and quantification Vertical & lateral Chemical mapping Electron microscopy observations DLR XPS atomic concentrations of elements Raman microscopic PTFE and C distribution of GDLs CEA Fresh PEMFC MEA ATR IR (C-F bonds) macroscopic PTFE & ionomer distribution in the new and aged PEFC and DMFC electrode layers SEM General aspect of the membrane and MEA FEG-SEM Active layer structure Cathode: C-Fiber Paper Cathode: MPL Cathode: CL Anode (PtRu) Cathode (Pt) TEM + ulramicrotomy catalyst layer and particles

8 cathode IR Peak Areas of PTFE or Nafion anode cathode IR Peak Areas of PTFE or Nafion anode cathode 1 3 Counts/s 1 3 Counts/s 1 3 Counts/s 1 3 Counts/s! Pt4f AGED Micro Porous Layer (IRD-AALE cell6). at% ANODE.11 +/-.6 at% (outlet) Ru3p CATHODE.44 +/-.9 at%.14 +/-.6 at% 18 (outlet) Aged 54 Ru3p Etch Time [s] /-.2 at% Characterizations Ru3p for degradation investigation and quantification DLR 1..5 VIRGIN Micro Porous Layer (IRD-AB2F). at%. at% Ru3p ANODE CATHODE x Etch Time [s] Vertical & lateral Chemical mapping NA Pt4f Pt4f x1.4 +/-.6 at% Pt4f /2 1. Technical Accomplishments and Progress CEA Electron microscopy observations Binding Energy [ev] Binding Binding Energy Energy [ev] [ev] 3 Aged DMFC stack (fuel starvation) AALE - Cell 6 Reference Inlet Flow Field Outlet 3 aged MEA AB2F - Reference Inlet Flow Field Outlet MEA XPS detection of Ru cathode side Aged Binding Energy [ev] Fresh PEMFC MEA Cycled PEMFC MEA Aged NA NA Aged NA 1 GDL GDL MPL MPL CCM IR-ATR changes due to ageing mainly in the CCMs CCM No main modifications : membrane not damaged, active layer structure similar to non aged Analysis of other aged samples from stack and single cell DMFC & PEMFC Impact of the testing conditions on the components degradation

9 distance from membrane in anode CL / m! cell voltage / V /2 1. Technical Accomplishments and Progress,6,4 Degradation models DLR Detailed basic model developed basis for degradation studies (transient behaviour, EIS) Degradation mechanism implemented 3,5x1-5 3,x1-5 2,5x1-5 2,x1-5 1,5x1-5 1,x1-5 5,x1-6 Ru-dissolution occurs first close to mb 1x1 5 2x1 5 3x1 5 4x1 5 t / s.1a/cm².2a/cm².3a/cm².4a/cm²,e+ 2,45E-3 4,9E-3 7,35E-3 9,8E-3 1,23E-2 1,47E-2 1,71E-2 1,96E-2 Ruthenium volume fraction DMFC cell modeling POLIMI Dev of electrochemical impedance model coupling phenomena interpretation Single cell model (incl. water transport) Simulated and measured o water fluxes at cathode outlet Water fluxes description Simulation of the flooding effect,2 Effect relevant mainly at high i,, 2,x1 5 4,x1 5 6,x1 5 8,x1 5 1,x1 6 time / s To be validated Evolution of physical parameters to be integrated for DMFC degradation modelling

10 Tension (mv)! Surface spécifique (m^2/m^3) /2 1. Technical Accomplishments and Progress Densité de courant (A/m 3 ) Surface spécifique (m 2 /m 3 ) Degradation models PEMFC cell modeling CEA x U (mv) gamma_c (m^2/m^3) Degradation à I=.6A/cm^ Temps (h) Parameters degradation estimated for each local conditions Global degradation of the cell voltage Global degradation of the active surface area 3.E+7 2.5E+7 2.E+7 1.5E+7 1.E+7 5.E+6.E Active layer thickness x Local current Epaisseur couche active (m) density distribution after ageing 1 x Land - Channel - Land Largeur canal+dent (m) -1 Amplification of the initial heterogeneities x Related Pt active area distribution x Epaisseur couche active (m) x 1-3 Largeur canal+dent (m) To be correlated with experimental degradation of components and performance regarding the different conditions and protocols

11 /3 2. Alignment to MAIP/AIP Correlation of the project with the corresponding Application Area (as mentioned in MAIP/AIP documents) Application area: Stationary Power Generation emphasis on long-term basic research to better understand degradation/failure mechanisms and the lifetime requirements of all fuel cell stack types (SOFC, MCFC, PEMFC), for different fuels and levels of power. For lifetime predictions, research is necessary to establish methodologies as well as tools for modelling, operational controls and diagnostics. Topic: Fundamentals of fuel cell degradation for stationary power application Research on critical parameters and operating conditions that impact degradation and life time of cells and stacks, for all power ranges and fuel cell technologies

12 /3 2. Alignment to MAIP/AIP Detailed project activities & results versus MAIP/AIP document targets Direct link between previously described activities & targets (Cf. approach slides) Specific degradation mechanisms for PEFC operating with methanol and reformate Application Technical activities - µ-chp systems with different requirements - 2 Fuel Cell types / fuels : DMFC (Methanol) & PEMFC (reformate) - Power ranges: from 5W stack to 3kWe PEM CHP syst. - FC tests (system, stack and cell levels): nominal and critical conditions - Studies of the microstructure & properties before/after ageing - Modelling of the degradation mechanisms Identification of main parameters enhancing degradation Development of accelerated tests Proposal & validation of lifetime prediction methodology

13 /3 2. Alignment to MAIP/AIP Identify and comment on gaps/bottlenecks in RTD&D proposed by MAIP/AIP documents Most topics of are considered in the MAIP/AIP DMFC technology is not directly included in the implementation plan whereas currently subjected to a significant commercial interest Comments on priorities and topics possibly under/over-estimated in the AIPs in terms of technical challenge For stationary applications, degradation understanding and durability improvement are the right priorities Durability of 4 hours: too wide requirement more focused targets to be proposed / specific application technical challenges to be more related to components or operating conditions constraints

14 /4 3. Cross-cutting issues Training and Education Post-doctoral researchers, PhD and MSc students involved in activities at CEA, DLR & POLIMI Polimi personal exchange: M. Zago DLR from 6/12 to 8/12 F. Bresciani IRD Fuel Cell 8/12 to 1/12 Safety, Regulations, Codes and Standards Possibility to contribute to future standards definition thanks to project outcomes on traditional and accelerated testing & on degradation models Dissemination & public awareness Journal publication: Zago, M., Casalegno, A., Santoro, C., Marchesi, R. Water transport and flooding in DMFC: Experimental and modeling analyses, 212, Journal of Power Sources 217, pp results to be presented at FC papers & conferences (incl. exhibition for indust.) (All partners) [ex: FDFC 213] workshop

15 /5 4. Enhancing cooperation and future perspectives Technology Transfer / Collaborations Interaction with EU projects Use of knowledge & results from DECODE project [degradation mechanisms, modelling data, investigation methods] Exchanges posssible with new projects e.g. IMPACT, IMPALA, PUMAMIND [degradation, water management, modelling] Interactions at national level (French, German, Italian or Danish FC projects) Possible exchanges and use of knowledge & results from national funded or other collaborative projects (all partners) Interaction with the national Real FC project : exchanges regards experimental data and testing methodology (POLIMI - Italy) Interactions at international level Possible exchanges about methodologies (for all technical aspects of testing, characterization or modelling) thanks to: close direct relationships with other industrial groups, institutes or universities involvement in international working groups (IEA, standardization bodies )

16 /5 4. Enhancing cooperation and future perspectives Project Future Perspectives Proposed future research approach and relevance & Need/opportunities [for increasing cooperation, building alliances & for international collaboration] RTD topics: Emphasis on fuel/methanol purity Development of more generic ACCT for DMFC and PEMFC : balanced consortium with 3 industries developing FC systems possible extended collaboration for further optimisation of the FC systems studied possible extension to other industries or institutes interested in the approach At international level: contribution to future definition of RCS (methanol purity, degradation tests or models) Possible contribution to the future FCH JU Programme Include research and demonstration of methanol/greenfuel based fuel cells e.g. DMFC in the implementation pl Recommendations for projects dedicated to specific systems development: Proposition of; exp./model methodology for degradation study; ex-situ investigation methods and testing protocols; validated prediction methodology

17 Thank you for your attention