J. H. Al-Smail 
 King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia
We develop a porosity-optimization problem to improve the electrochemical reactions taking place in hydrogen fuel cells. We introduce a mathematical model, which involves a system of conservation laws defined in a porous space domain. Our goal is to find the domain's optimal porosity function that can make the oxygen-hydrogen reaction as uniform as possible. The optimal porosity design ...
Screening Effects in Probing the Electric Double Layer by Scanning Electrochemical Potential Microscopy
R.F. Hamou, P.U. Biedermann, A. Erbe, and M. Rohwerder
Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany
A computational method is developed to study probing the electric double layer by Scanning Electrochemical Potential Microscopy. The model is based on a modified Poisson- Boltzmann equation, which takes into account steric effects. We investigated the effect of metallic apex protrusion and the Open Circuit Potential (OCP) of the tip on the probed potential. A clear electrostatic screening effect ...
G. C. Bandlamudi[1,2], C. Siegel, C. Heßke, and A. Heinzel[1,2]
ZBT Duisburg, Duisburg, Germany
University of Duisburg-Essen, Duisburg, Germany
High temperature polymer electrolyte membrane fuel cells (HT PEMFCs) are very promising technologies when used in combined cooling and heating power (CCHP) systems. They are operated at 160°C, offering the possibility of high tolerance to fuel impurities and a possibility to use the heat generated for cooling and heating purposes, leading to higher total system efficiency. Employing a 24 ...
X. Guan, E. Gratz, U. Pal
Division of Materials Science and Engineering, Boston University, Brookline, MA, USA
Computational fluid dynamics (CFD) modeling is a useful tool to gain an insight into various high temperature metallurgical processes such as the magnesium refining and the magnesium solid oxide membrane (SOM) electrolysis. In both processes, argon gas was used to stir the molten salt (flux) in order to improve the transport of magnesium vapor out of the flux and achieve chemical homogeneity in ...
D. Mi ,
 KEISOKU Engineering System Co., Ltd., Chiyoda-ku, Tokyo, Japan
Optimization of a typical electrochemical system with insulating shields is considered in this work, which objective is to reduce the current peak due to singularity and smooth the current density distribution along electrode surface. Moving mesh method was adopted to allow change in design variables, i.e., position and width of the insulating shields. It was found that combining optimization ...
J. Drillet ,
 DECHEMA-Forschungsinstitut, Frankfurt, Germany
This work aims at the modelling of a 5 cm^2 Direct Methanol Fuel Cell (DMFC) with mixed serial/parallel serpentine flow fields in terms of current/voltage behavior. One of the main challenge to overcome consists on lowering the so-called methanol cross over from the anode through the polymer membrane to the cathode that is responsible for mixed-potential formation at the cathode where both ...
Current Density Simulations in the Electrodeposition from Ionic Liquids: Effects of the Conductivity
I. Perissi, C. Borri, S. Caporali, and A. Lavacchi
Department of Chemistry, University of Firenze, Sesto Fiorentino, FI, Italy
The overall goal of this work is the use of COMSOL Multiphysics® in the modeling of the current density distributions for the electrodeposition of aluminum coatings from ionic liquids. The local current distribution is strongly dependant on the conductivity and on the geometry of the galvanic cell and can only be computed by the numerical solution of the partial differential equations ...
Michael A. Vallance
Team Leader, GE Global Research
Over time, rechargeable batteries degrade and eventually stop working. You see some combination of declining capacity, rapid self-discharge, and reduced power. Degradation mode depends on battery design, but also on the application. Often, multiple physical processes contribute to degradation. In the laboratory, you can measure performance degradation. You can dissect the battery to discover ...
M. N. Nandanwar, S. K. Gupta
Indian Institute of Science, Bangalore, India
Failure of conventional lead-acid battery is attributed to degradation of solid active mass (PbO2 and PbSO4 ). A number of research efforts are underway worldwide to overcome degradation of active mass to improve the cycle life of lead-acid batteries. Soluble lead-acid flow battery (SLFB) is a new kind of lead-acid flow battery in which products of discharge remain in dissolved state. SLFB ...
S. Skoda, E. Robalinho, E. F. Cunha, M. Linardi
Instituto de Pesquisas Energéticas e Nucleares - IPEN/CNEN-SP, São Paulo, SP, Brazil
Universidade Nove de Julho - UNINOVE, São Paulo, SP, Brazil
The use of numerical techniques in PEM fuel cell sensoring represents an advantage of project engineering, reducing the costs and accelerating the manufacturing of prototypes. In this work some numerical responses are shown, relating to numerical sensoring of water and oxygen mole fractions at cathode of a 5 cm² of geometric area PEM fuel cell. The need to recognize a geometric figure of merit ...