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‣ Modeling and simulation of micro direct methanol Fuel Cells

Falcão, D. S.; Oliveira, V. B.; Oliveira, M. S. N.; Rangel, C. M.
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em 10/11/2011 Português
Relevância na Pesquisa
28.324893%
Fuel cells have unique technological attributes: efficiency, absence of moving parts and low emissions. The Direct Methanol Fuel Cell (DMFC) has attracted much attention due to its potential applications as a power source for transportation and portable electronic devices. With the advance of micromachining technologies, miniaturization of power sources became one of the trends of evolution of research in this area. Based on the advantages of the scaling laws, miniaturization promises higher efficiency and performance of power generating devices, so, MicroDMFC is an emergent technology. Models play an important role in fuel cell development since they facilitate a better understanding of parameters affecting the performance of fuel cells. In this work, a steady state, one-dimensional model accounting for coupled heat and mass transfer, along with the electrochemical reactions occurring in a fuel cell, already developed and validated for DMFC in [1-3], is used to predict Micro DMFC performance. The model takes in account all relevant phenomena occurring in a DMFC. Polarization curves predicted by the model are compared with experimental data existing in literature and the model shows good agreement, mainly for lower current densities. The model is used to predict some important parameters to analyze fuel cell performance...

‣ Micro direct methanol fuel cell: experimental and modelling studies

Falcão, D. S.; Rangel, C. M.; Pinto, A. M. F. R.
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em //2013 Português
Relevância na Pesquisa
28.580652%
The Direct Methanol Fuel Cell (DMFC) has attracted much attention due to its potential applications as a power source for transportation and portable electronic devices. Based on the advantages of the scaling laws, miniaturization promises higher efficiency and performance of power generating devices and the MicroDMFC is therefore an emergent technology. In this work, a set of experiences with a MicroDMFC of 2.25 cm2 active area are performed in order to investigate the effect of important operating parameters. The cell is presented in Fig. 1. The experimental rig consists in a rotameter for air flow, a peristaltic pump (Control CO) for methanol flow and an electrochemical station (Zahner) to obtain polarization curves. The effect of the methanol concentration on the cell performance, between 3 and 5 M was studied. All the experiments were performed at room temperature, a condition of special interest with view to portable applications. Maximum power density achieved was 32.6 m /cm2 using a 4 M methanol concentration at room temperature. Polarization curves are compared with mathematical model simulations in order to achieve a better understanding of how parameters affect performance. The one-dimensional model used in this work takes in account coupled heat and mass transfer...

‣ Experimental and modeling studies of a micro direct methanol fuel cell

Falcão, D. S.; Rangel, C. M.; Pinto, A. M. F. R.
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em //2013 Português
Relevância na Pesquisa
28.580652%
The Direct Methanol Fuel Cell (DMFC) has attracted much attention due to its potential applications as a power source for transportation and portable electronic devices. Based on the advantages of the scaling laws, miniaturization promises higher efficiency and performance of power generating devices and the MicroDMFC is therefore an emergent technology. In this work, a set of experiences with a MicroDMFC of 2.25 cm2 active area are performed in order to investigate the effect of important operating parameters. Maximum power density achieved was 32.6 mW/cm2 using 4M mehanol concentration at room temperature. Polarization curves are compared with mathematical model simulations in order to achieve a better understanding of how parameters affect performance. The one-dimensional model used in this work takes in account coupled heat and mass transfer, along with the electrochemical reactions occurring in a direct methanol fuel cell and was already developed and validated for DMFC in previous work [1-3]. The model is also used to predict some important parameters to analyze fuel cell performance, such as water transport coefficient and methanol crossover. This easy to implement simplified model is suitable for use in real-time MicroDMFC simulations.