elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Investigation of Current Density Distributions of PEM Fuel Cells during Cold Start-up

Friedrich, K. Andreas and Rui, Lin and Garcia Sanchez, Daniel and Gülzow, Erich (2013) Investigation of Current Density Distributions of PEM Fuel Cells during Cold Start-up. Meeting of the International Society of Electrochemistry 2013, 9.09.-13.09.2013, Queretaro, Mexico.

[img] PDF - Registered users only
1MB

Abstract

The possibility to start-up polymer fuel cells from freezing temperatures is an essential requirement of the automotive application for fuel cell power trains. Even though car manufacturers have found a practical solution to the cold start issue by purging and thereby drying the cells during shut down - thereby avoiding strong degradation by ice formation in gas diffusion layers and flow fields - not much is known about the electrochemical processes during cold start-up. This is however required to avoid gradual degradation and life-time limitations. In this study we investigate the current density distribution of a stack during the start-up from -20 °C. A short stack is exposed at freezing temperatures and investigated in during start-up in a fuel cell test station with segmented sensor plates. Before freezing the cells are dryed (see Figure 1). The found heterogeneities are correlated with integral polarization and cell resistance tests at different flow conditions. Furthermore, cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) provide some additional information about the changes during the start-up after freezing conditions. In addition we investigate the microscopic conductivity distribution of Nafion® membranes by conductive atomic force microscopy at freezing temperatures below -15 °C. The conductivity structure is correlated with extensive investigations available at elevated temperatures. The implications for start-up procedures will be shortly discussed.

Item URL in elib:https://elib.dlr.de/85711/
Document Type:Conference or Workshop Item (Speech)
Title:Investigation of Current Density Distributions of PEM Fuel Cells during Cold Start-up
Authors:
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Friedrich, K. Andreasandreas.friedrich (at) dlr.deUNSPECIFIED
Rui, LinTongji UniversityUNSPECIFIED
Garcia Sanchez, DanielDaniel.GarciaSanchez (at) dlr.deUNSPECIFIED
Gülzow, Ericherich.guelzow (at) dlr.deUNSPECIFIED
Date:10 September 2013
Refereed publication:No
Open Access:No
Gold Open Access:No
In SCOPUS:No
In ISI Web of Science:No
Status:Published
Keywords:cold start Polymer electrolyte fuel cell
Event Title:Meeting of the International Society of Electrochemistry 2013
Event Location:Queretaro, Mexico
Event Type:international Conference
Event Dates:9.09.-13.09.2013
Organizer:International Society of Electrochemistry
HGF - Research field:Energy
HGF - Program:Efficient Energy Conversion and Use (old)
HGF - Program Themes:Fuel Cells (old)
DLR - Research area:Energy
DLR - Program:E EV - Energy process technology
DLR - Research theme (Project):E - Elektrochemische Prozesse (old)
Location: Stuttgart
Institutes and Institutions:Institute of Engineering Thermodynamics > Electrochemical Energy Technology
Deposited By: Friedrich, Prof.Dr. Kaspar Andreas
Deposited On:26 Nov 2013 10:34
Last Modified:01 Dec 2018 19:49

Repository Staff Only: item control page

Browse
Search
Help & Contact
Information
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.