Formation of Protective Nitride Surfaces for PEM Fuel Cell Metallic Bipolar Plates
Abstract
Selective gas nitridation of model Ni-base alloys was used to form dense, electrically-conductive and corrosion-resistant nitride surface layers, including TiN, VN, CrN, Cr2N, as well as a complex NiNbVN phase. Evaluation for use as a protective surface for metallic bipolar plates in proton exchange membrane fuel cells (PEMFC) indicated that CrN/Cr2N base surfaces hold promise to meet Department of Energy (DOE) performance goals for automotive applications. The thermally grown CrN/Cr2N surface formed on model Ni-Cr base alloys exhibited good stability and low electrical resistance in single-cell fuel cell testing under simulated drive-cycle conditions. Recent results indicate that similar protective Cr-nitride surfaces can be formed on less expensive Fe-Cr base alloys potentially capable of meeting DOE cost goals.
- Authors:
- ORNL
- National Renewable Energy Laboratory (NREL)
- Los Alamos National Laboratory (LANL)
- Publication Date:
- Research Org.:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); High Temperature Materials Laboratory; Shared Research Equipment Collaborative Research Center
- Sponsoring Org.:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE)
- OSTI Identifier:
- 1003560
- DOE Contract Number:
- DE-AC05-00OR22725
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Journal of the Minerals Metals & Materials Society (JOM); Journal Volume: 58; Journal Issue: 8
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 30 DIRECT ENERGY CONVERSION; ALLOYS; ELECTRIC CONDUCTIVITY; EVALUATION; FUEL CELLS; NITRIDATION; NITRIDES; PERFORMANCE; PLATES; PROTON EXCHANGE MEMBRANE FUEL CELLS; STABILITY; TESTING; fuel cell; coating; bipolar plate; nitride; corrosion
Citation Formats
Brady, Michael P, Yang, Bing, Wang, Heli, Turner, John, More, Karren Leslie, Wilson, Mahlon, and Garzon, Fernando. Formation of Protective Nitride Surfaces for PEM Fuel Cell Metallic Bipolar Plates. United States: N. p., 2006.
Web. doi:10.1007/s11837-006-0054-4.
Brady, Michael P, Yang, Bing, Wang, Heli, Turner, John, More, Karren Leslie, Wilson, Mahlon, & Garzon, Fernando. Formation of Protective Nitride Surfaces for PEM Fuel Cell Metallic Bipolar Plates. United States. doi:10.1007/s11837-006-0054-4.
Brady, Michael P, Yang, Bing, Wang, Heli, Turner, John, More, Karren Leslie, Wilson, Mahlon, and Garzon, Fernando. Sun .
"Formation of Protective Nitride Surfaces for PEM Fuel Cell Metallic Bipolar Plates". United States.
doi:10.1007/s11837-006-0054-4.
@article{osti_1003560,
title = {Formation of Protective Nitride Surfaces for PEM Fuel Cell Metallic Bipolar Plates},
author = {Brady, Michael P and Yang, Bing and Wang, Heli and Turner, John and More, Karren Leslie and Wilson, Mahlon and Garzon, Fernando},
abstractNote = {Selective gas nitridation of model Ni-base alloys was used to form dense, electrically-conductive and corrosion-resistant nitride surface layers, including TiN, VN, CrN, Cr2N, as well as a complex NiNbVN phase. Evaluation for use as a protective surface for metallic bipolar plates in proton exchange membrane fuel cells (PEMFC) indicated that CrN/Cr2N base surfaces hold promise to meet Department of Energy (DOE) performance goals for automotive applications. The thermally grown CrN/Cr2N surface formed on model Ni-Cr base alloys exhibited good stability and low electrical resistance in single-cell fuel cell testing under simulated drive-cycle conditions. Recent results indicate that similar protective Cr-nitride surfaces can be formed on less expensive Fe-Cr base alloys potentially capable of meeting DOE cost goals.},
doi = {10.1007/s11837-006-0054-4},
journal = {Journal of the Minerals Metals & Materials Society (JOM)},
number = 8,
volume = 58,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
-
Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni-Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitridemore »
-
Protective nitride formation on stainless steel alloys for proton exchange membrane fuel cell bipolar plates
Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni–Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitridemore » -
SnO2:F Coated Ferritic Stainless Steels for PEM Fuel Cell Bipolar Plates
Ferrite stainless steels (AISI441, AISI444, and AISI446) were successfully coated with 0.6 {micro}m thick SnO{sub 2}:F by low-pressure chemical vapor deposition and investigated in simulated PEMFC environments. The results showed that a SnO{sub 2}:F coating enhanced the corrosion resistance of the alloys in PEMFC environments, though the substrate steel has a significant influence on the behavior of the coating. ICP results from the testing solutions indicated that fresh AISI441 had the highest dissolution rates in both environments, and coating with SnO2:F significantly reduced the dissolution. Coating AISI444 also improved the corrosion resistance. Coating AISI446 steel further improved the already excellentmore » -
-
SnO2:F Coated Duplex Stainless Steel for PEM Fuel Cell Bipolar Plates
Duplex 2205 stainless steel was deposited with 0.6 {micro}m thick SnO2:F coating; coated steel was characterized for PEMFC bipolar plate application. Compared with bare alloy, interfacial contact resistance (ICR) values of the coated 2205 steel are higher. SnO2:F coating adds its own resistance to the air-formed film on the steel. In a PEMFC anode environment, a current peak of ca. 25 {micro}A/cm2 registered at ca. 30 min for coated 2205 steel. It stabilized at ca. 2.0 {approx} -1.0 {micro}A/cm2. This peak is related to the complicated process of coating dissolution and oxide-layer formation. Anodic-cathodic current transfer occurred at ca. 200more »