Performance Analysis of a Direct Methanol Fuel Cell Stack With Bipolar Plate Incorporated With Innovative Flow-Field Combination

Increasing interest in utilizing direct methanol fuel cells for portable applications has prompted the need for understanding of their operating characteristics. Approximately 80% of a direct methanol fuel cell stack's volume and weight arise from the bipolar plates. The bipolar plates have grooved anode and cathode flow fields, and have a critical influence on the cell stack performance and stability. However, there is little published data regarding design expansion from single cell to stack, and literature regarding the fuel/oxidant distribution in each cell is especially scant. Hence, this topic is the subject of the present study, which reports the design of a complete direct methanol fuel cell consisting of five single cells including a graphite bipolar plate, as well as an innovative anode and cathode flow channel design. By observing variations in operating parameters, such as applied load and the flow of methanol solution and air, the impact of each parameter on the output performance and stability of the stack was investigated.

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Direct methanol fuel cell modeling based on the norm optimal iterative learning control

Proceedings of the Institution of Mechanical Engineers Part I Journal of Systems and Control Engineering ◽

10.1177/0959651820904800 ◽

2020 ◽

Vol 235 (1) ◽

pp. 68-79

Author(s):

Nastaran Shakeri ◽

Zahra Rahmani ◽

Abolfazl Ranjbar Noei ◽

Mohammadreza Zamani

Keyword(s):

Fuel Cell ◽

Iterative Learning Control ◽

Direct Methanol Fuel Cell ◽

Direct Methanol Fuel Cells ◽

Learning Control ◽

Iterative Learning ◽

Operating Conditions ◽

Primary Model ◽

Direct Methanol ◽

Methanol Fuel Cell

Direct methanol fuel cells are one of the most promisingly critical fuel cell technologies for portable applications. Due to the strong dependency between actual operating conditions and electrical power, acquiring an explicit model becomes difficult. In this article, the behavioral model of direct methanol fuel cell is proposed with satisfactory accuracy, using only input/output measurement data. First, using the generated data which are tested on the direct methanol fuel cell, the frequency response of the direct methanol fuel cell is estimated as a primary model in lower accuracy. Then, the norm optimal iterative learning control is used to improve the estimated model of the direct methanol fuel cell with a predictive trial information algorithm. Iterative learning control can be used for controlling systems with imprecise models as it is capable of correcting the input control signal in each trial. The proposed algorithm uses not only the past trial information but also the future trials which are predicted. It is found that better performance, as well as much more convergence speed, can be achieved with the predicted future trials. In addition, applying the norm optimal iterative learning control on the proposed procedure, resulted from the solution of a quadratic optimization problem, leads to the optimal selection of the control inputs. Simulation results demonstrate the effectiveness of the proposed approach by practical data.

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A Novel Button-Type Micro Direct Methanol Fuel Cell with Graphene Diffusion Layer

Micromachines ◽

10.3390/mi10100658 ◽

2019 ◽

Vol 10 (10) ◽

pp. 658

Author(s):

Zhu ◽

Gao ◽

Keyword(s):

Fuel Cell ◽

Power Density ◽

Direct Methanol Fuel Cell ◽

Direct Methanol Fuel Cells ◽

Effective Area ◽

Unit Weight ◽

Specific Power ◽

Large Area ◽

Direct Methanol ◽

Methanol Fuel Cell

In order to solve the problem that bolts in traditional packaged direct methanol fuel cells (DMFCs) take up a large area and reduce the specific energy (energy per unit weight) and power density (power per unit area), a new button-type micro direct methanol fuel cell (B-μDMFC) is designed, assembled, and packaged. The cell with four different structures was tested before and after packaging. The results indicate that the button cell with three-dimensional graphene and springs has the best performance. The equivalent circuit and methanol diffusion model was applied to explain the experimental results. The peak volumetric specific power density of the cell is 11.85 mW cm−3. This is much higher than traditional packaged DMFC, because the novel B-μDMFC eliminates bolts in the structure and improves the effective area ratio of the cell.

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A self-pumping and self-breathing micro direct methanol fuel cell with polymer bipolar plates

Journal of Power Sources ◽

10.1016/j.jpowsour.2011.03.037 ◽

2011 ◽

Vol 196 (18) ◽

pp. 7533-7540 ◽

Cited By ~ 19

Author(s):

Lingjun Sun ◽

Chong Liu ◽

Junsheng Liang ◽

Xuelin Zhu ◽

Tianhong Cui

Keyword(s):

Fuel Cell ◽

Direct Methanol Fuel Cell ◽

Bipolar Plates ◽

Direct Methanol ◽

Methanol Fuel Cell

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Operating characteristics and performance stability of 5 W class direct methanol fuel cell stacks with different cathode flow patterns

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2010.02.018 ◽

2011 ◽

Vol 36 (2) ◽

pp. 1853-1861 ◽

Cited By ~ 13

Author(s):

Young-Chul Park ◽

Dong-Hyun Peck ◽

Sang-Keun Dong ◽

Sang-Kyung Kim ◽

Seongyop Lim ◽

...

Keyword(s):

Fuel Cell ◽

Direct Methanol Fuel Cell ◽

Flow Patterns ◽

Operating Characteristics ◽

Direct Methanol ◽

And Performance ◽

Methanol Fuel Cell

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Evaluation of the Performance Characteristics of a Direct Methanol Fuel Cell With Multifuels

Journal of Fuel Cell Science and Technology ◽

10.1115/1.4000688 ◽

2010 ◽

Vol 7 (4) ◽

Cited By ~ 1

Author(s):

Sujith Mohan ◽

S. O. Bade Shrestha

Keyword(s):

Fuel Cell ◽

Direct Methanol Fuel Cell ◽

Direct Methanol Fuel Cells ◽

Operating Temperature ◽

High Energy ◽

High Energy Density ◽

Power Sources ◽

Transport Losses ◽

Direct Methanol ◽

Methanol Fuel Cell

Direct methanol fuel cells are one of the alternate power sources for the field of power electronics because of their high energy density. The benefits of a fuel cell toward the environment can be greatly improved if the fuel used for its application comes from renewable sources. In this study, the performance of a direct methanol fuel cell was investigated under five different methanol concentrations. The effect of methanol concentration on the cell operating temperature is studied. Impedance spectroscopy was conducted to measure the ohmic, activation, and mass transport losses for all concentrations. The cell performance was evaluated using methane and ethanol fuels and this was compared with methanol operation.

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Evaluation of the Performance Characteristics of a Direct Methanol Fuel Cell With Multi Fuels

ASME 2009 7th International Conference on Fuel Cell Science, Engineering and Technology ◽

10.1115/fuelcell2009-85161 ◽

2009 ◽

Author(s):

Sujith Mohan ◽

S. O. Bade Shrestha

Keyword(s):

Fuel Cell ◽

Direct Methanol Fuel Cell ◽

Direct Methanol Fuel Cells ◽

Operating Temperature ◽

High Energy ◽

High Energy Density ◽

Power Sources ◽

Transport Losses ◽

Direct Methanol ◽

Methanol Fuel Cell

Direct methanol fuel cells are one of the alternate power sources for the field of power electronics because of their high energy density. The benefits of a fuel cell towards the environment can be greatly improved if the fuel used for its application comes from renewable sources. In this study, the performance of a direct methanol fuel cell was investigated under five different methanol concentrations. The effect of methanol concentration on the cell operating temperature is studied. Impedance spectroscopy was conducted to measure the ohmic, activation and mass transport losses for all concentrations. The cell performance was evaluated using methane and ethanol fuels and this was compared with methanol operation.

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