Effect of electrical current on the oxidation behavior
of electroless nickel-plated ferritic stainless steel in
solid oxide fuel cell operating conditions
John Ryter
a
, Roberta Amendola
a,*
, Madisen McCleary
a
, Wei-Ja Shong
b
,
Chien-Kuo Liu
b
, Roberto Spotorno
c
, Paolo Piccardo
c
a
Department of Mechanical & Industrial Engineering, Montana State University, Bozeman, MT 59717, USA
b
Nuclear Fuels and Materials Division, Institute of Nuclear Energy Research, Longtan, Taoyuan 32546, Taiwan, ROC
c
Department of Chemistry and Industrial Chemistry, University of Genoa, Genoa 16146, Italy
article info
Article history:
Received 27 September 2017
Received in revised form
30 October 2017
Accepted 6 November 2017
Available online xxx
Keywords:
SOFC
Ferritic stainless steel
High temperature oxidation
Electroless Ni plating
abstract
Planar solid oxide fuel cell (SOFC) systems often employ metallic interconnects, which
separate and connect individual cells in electrical series to create a stack. Coated and
uncoated ferritic stainless steels (FSSs), are reported among the most promising materials
currently being investigated for interconnect applications. In this study, FSS AISI 441
samples coated with electroless nickel (~25 mm) were subjected to intermediate tempera-
ture IT-SOFC operating conditions at 700
C for 500 h with and without the application of
electrical current (0.5 Acm
2
). The application of the electric current promotes Fe migration
on both the cathode and the anode side. This phenomenon results in the formation of a
~4 mm thick Fe
2
O
3
on the anode side responsible for increased ASR values. Comparative
analyses of the current and no current exposures and resultant surface oxide layers, along
with suspected mechanisms and implications are presented and discussed.
© 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Introduction
Solid Oxide Fuel Cells (SOFCs) are devices used to instigate a
solid state electrochemical conversion, producing electricity
and heat by oxidizing a fuel, typically hydrogen [1]. Due to
their high efficiency and low emissions, SOFCs have risen
both in importance and popularity as a method of both large-
and small-scale power generation. They are composed of
four functional component elements: the cathode, anode,
electrolyte, and interconnect (IC). Each individual fuel cell
produces very little electrical power, and as a result cells
must be connected in series to produce enough power for
SOFCs to function as a viable source of energy. The IC
component provides the electrical connection between
adjacent cells in the stack and is consequently exposed to air
at the cathode side and a fuel (e.g. hydrogen) at the anode
side. This exposure condition is known as dual atmosphere
(DA), as opposed to an air-only, environment known as single
atmosphere (SA) [2].
Interconnect materials must interface seamlessly with
other SOFC elements, requiring thermal and chemical
* Corresponding author.
E-mail addresses: ryterj@live.com (J. Ryter), roberta.amendola@montana.edu (R. Amendola), m.mccleary39@gmail.com
(M. McCleary), wjshong@iner.gov.tw (W.-J. Shong), ckliu2@iner.gov.tw (C.-K. Liu), roberto.spotorno87@gmail.com (R. Spotorno), Paolo.
piccardo@unige.it (P. Piccardo).
Available online at www.sciencedirect.com
ScienceDirect
journal homepage: www.elsevier.com/locate/he
international journal of hydrogen energy xxx (2017) 1 e9
https://doi.org/10.1016/j.ijhydene.2017.11.055
0360-3199/© 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Please cite this article in press as: Ryter J, et al., Effect of electrical current on the oxidation behavior of electroless nickel-plated ferritic
stainless steel in solid oxide fuel cell operating conditions, International Journal of Hydrogen Energy (2017), https://doi.org/10.1016/
j.ijhydene.2017.11.055