HDCFC Performance as a Function of Anode Atmosphere (N2-CO2)

Lisa Deleebeeck, Kent Kammer Hansen

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

The mechanism for the oxidation of solid carbon in a fuel cell made as a hybrid between a molten carbonate fuel cell and a solid oxide fuel cell, known as a hybrid direct carbon fuel cell (HDCFC), was investigated: Fuel cell performance was measured by electrochemical impedance spectroscopy (EIS) and using current-potential-power density curves (I-V-P) between 700 to 800 degrees C. The impacts of the gas species introduced at the cathode (air vs. pure O-2) and at the anode (pure N-2, pure CO2, and mixed N-2-CO2) were investigated, as well as the influences of temperature and anode gas flow rate. The majority of the impedance data could be modeled using an equivalent circuit consisting of a resistor (Rs) in series with three resistor-constant phase element units (RQ, in parallel), depending on anode gas atmosphere. An explanation was proposed for each impedance element, and the literature relating to impedance data acquired for carbon-carbonate mixture in a DCFC anode were discussed. By varying of the anode gas mixtures between pure N-2 and pure CO2, together with variations in their flow rates, it was suggested that CO2 is a chemically active species which is not electrochemically active, a chemical intermediate in the oxidation of solid carbon in such a HDCFC. (C) 2013 The Electrochemical Society.
Original languageEnglish
JournalJournal of The Electrochemical Society
Volume161
Issue number1
Pages (from-to)F33-F46
ISSN0013-4651
DOIs
Publication statusPublished - 2014

Keywords

  • ELECTROCHEMISTRY
  • MATERIALS
  • CARBON FUEL-CELL
  • ELECTROCHEMICAL OXIDATION
  • SOLID OXIDE
  • DIRECT CONVERSION
  • ELECTROLYTE
  • GASIFICATION
  • IMPEDANCE
  • GRAPHITE
  • SLURRIES
  • FUTURE
  • Carbon
  • Direct carbon fuel cells (DCFC)
  • Electrochemical impedance spectroscopy
  • Flow rate
  • Mixtures
  • Molten carbonate fuel cells (MCFC)
  • Reaction intermediates
  • Resistors
  • Carbon dioxide
  • Active species
  • Chemical intermediates
  • Density curves
  • Fuel cell performance
  • Impedance data
  • Impedance elements
  • Phase element
  • Solid carbon
  • Fuel Cells, Electrolyzers, and Energy Conversion

Fingerprint Dive into the research topics of 'HDCFC Performance as a Function of Anode Atmosphere (N<sub>2</sub>-CO<sub>2</sub>)'. Together they form a unique fingerprint.

Cite this