Effects of Operating Conditions on Direct Methanol Fuel Cell Performance Using Nafion-Based Polymer Electrolytes

2014 ◽  
Vol 11 (6) ◽  
Author(s):  
Shingjiang Jessie Lue ◽  
Wei-Luen Hsu ◽  
Chen-Yu Chao ◽  
K. P. O. Mahesh
Keyword(s):  
Fuel Cell ◽  
Flow Rate ◽  
Direct Methanol Fuel Cell ◽  
Methanol Solution ◽  
Operating Conditions ◽  
Methanol Concentration ◽  
Cell Performance ◽  
Stoichiometric Ratio ◽  
Direct Methanol ◽  
Methanol Fuel Cell

Systematic experiments were carried out to study the effects of various operating conditions on the performances of a direct methanol fuel cell (DMFC) using Nafion 117 and its modified membranes. The cell performance was studied as a function of cell operating temperature, methanol concentration, methanol flow rate, oxygen flow rate, and methanol-to-oxygen stoichiometric ratio. The experimental results revealed that the most significant factor was the temperature, increasing the cell performance from 50 to 80 °C. We achieved the maximum power density (Pmax) of 86.4 mW cm−2 for a DMFC at 80 °C fed with 1 M methanol (flow rate of 2 ml min−1) and humidified oxygen (80 ml min−1). A methanol concentration of 1 M gave much better performance than using 3 M of methanol solution. The oxygen and methanol flow rates with the same stoichiometric ratio had a beneficial effect on cell performance up to certain values, beyond which further increase in flow rate had limited effect. The Voc using argon plasma-modified Nafion was higher than the pristine Nafion membrane for the cell operated on 3 M methanol solution, which was due to the lower methanol permeability of the Ar-modified Nafion.

scholarly journals Effects of operating parameters on performance of a single direct methanol fuel cell

2010 ◽  
Vol 14 (2) ◽  
pp. 469-477 ◽  
Author(s):  
Ebrahim Alizadeh ◽  
Mousa Farhadi ◽  
Kurosh Sedighi ◽  
Mohsen Shakeri
Keyword(s):  
Fuel Cell ◽  
Flow Rate ◽  
Direct Methanol Fuel Cell ◽  
Cell Voltage ◽  
Oxygen Flow Rate ◽  
Methanol Concentration ◽  
Cell Performance ◽  
Oxygen Flow ◽  
Direct Methanol ◽  
Methanol Fuel Cell

In this study the effect of various operating conditions on 10 cm ?10 cm active area of in-house fabricated direct methanol fuel cell was investigated experimentally. The effect of the cell temperature, methanol concentration, and oxygen flow rate on cell performance was studied. The study reveals that current density is not monotonous function of temperature, but has an optimum operating condition for each cell voltage. The experiments also indicate that the cell performance increases with an increased of oxygen flow rate up to a certain value and then further increase has no significant effect. Furthermore, for methanol concentration greater than 1.5 M, a reduction of cell voltage was indicated which is due to an increase of methanol cross over.

Experimental Analysis of a Small-Scale Flowing Electrolyte–Direct Methanol Fuel Cell Stack

2015 ◽  
Vol 12 (4) ◽  
Author(s):  
Yashar Kablou ◽  
Cynthia A. Cruickshank ◽  
Edgar Matida
Keyword(s):  
Fuel Cell ◽  
Flow Rate ◽  
Power Output ◽  
Direct Methanol Fuel Cell ◽  
Operating Conditions ◽  
Solution Flow Rate ◽  
Small Scale ◽  
Solution Flow ◽  
Direct Methanol ◽  
Methanol Fuel Cell

A small-scale five-cell flowing electrolyte–direct methanol fuel cell (FE-DMFC) stack with U-type manifold configuration and parallel serpentine flow bed design was studied experimentally. The active area of a single cell was approximately 25 cm2. For every stack cell, diluted sulphuric acid was used as the flowing electrolyte (FE) which was circulated through a porous medium placed between two Nafion® 115 polymer electrolyte membranes. The stack performance was studied over a range of several operating conditions, such as temperature (50–80 °C), FE flow rate (0–17.5 ml/min), methanol concentration (0.5–4.0 M), and methanol solution flow rate (10–20 ml/min). In addition, the stack cell to cell voltage variations and the effects of the FE stream interruption on the output voltage were investigated at various operating loads. Experimental results showed that utilization of the FE effectively reduced methanol crossover and improved the stack power output. It was found that increasing the FE flow rate enhanced the stack capability to operate at higher inlet methanol concentrations without any degradation to the performance. The results also demonstrated that the stack power output can be directly controlled by regulating the FE stream especially at high operating currents.

Power Generation Experiment of Direct Methanol Fuel Cell

2011 ◽  
Vol 347-353 ◽  
pp. 3281-3285 ◽  
Author(s):  
Xin Zhou ◽  
Xiao Feng Xie ◽  
Motoo Ishikawa
Keyword(s):  
Fuel Cell ◽  
Flow Rate ◽  
Direct Methanol Fuel Cell ◽  
Peak Power ◽  
Gas Flow ◽  
Operating Conditions ◽  
Air Flow Rate ◽  
Direct Methanol ◽  
Oxygen Gas ◽  
Methanol Fuel Cell

An experiment of a single direct methanol fuel cell (DMFC) was conducted at Fuel Cell laboratory of Tsinghua University, China in collaboration with University of Tsukuba, Japan. Influences of the anodic methanol solution's concentration, the cathodic air flow rate, and the cathodic oxygen gas flow rate on the single DMFC performance were investigated to optimize operating conditions of the fuel cell. The experimental results have shown that the single DMFC can reach the peak power density of 0.170 W/cm2 with the current of 0.515 A/cm2 under the condition of the concentration of methanol solution of 2M and the flow rate of oxygen gas of 80 mL/min.

Performance of a Direct Methanol Fuel Cell Operating Close to Room Temperature

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
V. B. Oliveira ◽  
C. M. Rangel ◽  
A. M. F. R. Pinto
Keyword(s):  
Fuel Cell ◽  
Direct Methanol Fuel Cell ◽  
Gas Diffusion ◽  
Operating Conditions ◽  
Cell Performance ◽  
Methanol Crossover ◽  
Gas Diffusion Layers ◽  
Diffusion Layers ◽  
Direct Methanol ◽  
Methanol Fuel Cell

The direct methanol fuel cell (DMFC) is a promising power source for micro- and various portable electronic devices (mobile phones, PDAs, laptops, and multimedia equipment) with the advantages of easy fuel storage, no need for humidification, and simple design. However, a number of issues need to be resolved before DMFC commercialization, such as the methanol crossover and water crossover, which must be minimized in portable DMFCs. In the present work, a detailed experimental study on the performance of an “in-house” developed DMFC with 25 cm2 of active membrane area, working near the ambient conditions is described. The influence on the DMFC performance of the methanol concentration in the fuel feed solution and of both anode and cathode flowrates was studied. Tailored membrane electrode assemblies (MEAs) were designed in order to select optimal working conditions. Different structures and combinations of gas diffusion layers (GDLs) were tested. Under the operating conditions studied it was shown that, as expected, the cell performance significantly increases with the introduction of gas diffusion layers and that carbon cloth is more efficient than carbon paper both for the anode and cathode GDLs. The results reported allow the setup of tailored MEAs enabling the cell operation at high methanol concentrations (high power densities) without sacrificing performance (i.e., achieving low methanol crossover values). The influence of the different parameters on the cell performance is explained under the light of the predictions from a previously developed one-dimensional model, coupling heat and mass transfer effects. The main gain of this work is to report DMFC detailed experimental data at near ambient temperature which are insufficient in literature. This operating condition is of special interest in portable applications.

Experimental Investigation on the Performance of a Formic Acid Electrolyte-Direct Methanol Fuel Cell

2013 ◽  
Vol 11 (2) ◽  
Author(s):  
David Ouellette ◽  
Cynthia Ann Cruickshank ◽  
Edgar Matida
Keyword(s):  
Fuel Cell ◽  
Formic Acid ◽  
Power Output ◽  
Direct Methanol Fuel Cell ◽  
Operating Conditions ◽  
Portable Devices ◽  
Acid Electrolyte ◽  
Optimal Operating ◽  
Direct Methanol ◽  
Methanol Fuel Cell

The performance of a new methanol fuel cell that utilizes a liquid formic acid electrolyte, named the formic acid electrolyte-direct methanol fuel cell (FAE-DMFC) is experimentally investigated. This fuel cell type has the capability of recycling/washing away methanol, without the need of methanol-electrolyte separation. Three fuel cell configurations were examined: a flowing electrolyte and two circulating electrolyte configurations. From these three configurations, the flowing electrolyte and the circulating electrolyte, with the electrolyte outlet routed to the anode inlet, provided the most stable power output, where minimal decay in performance and less than 3% and 5.6% variation in power output were observed in the respective configurations. The flowing electrolyte configuration also yielded the greatest power output by as much as 34%. Furthermore, for the flowing electrolyte configuration, several key operating conditions were experimentally tested to determine the optimal operating points. It was found that an inlet concentration of 2.2 M methanol and 6.5 M formic acid, as along with a cell temperature of 52.8 °C provided the best performance. Since this fuel cell has a low optimal operating temperature, this fuel cell has potential applications for handheld portable devices.

Performance Estimation of Direct Methanol Fuel Cell Using Artificial Neural Network

2015 ◽  
Author(s):  
M. A. Rafe Biswas ◽  
Melvin D. Robinson
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Artificial Neural Networks ◽  
Fuel Cell ◽  
Direct Methanol Fuel Cell ◽  
Cell Voltage ◽  
Operating Conditions ◽  
Direct Methanol ◽  
Artificial Neural ◽  
Methanol Fuel Cell

A direct methanol fuel cell can convert chemical energy in the form of a liquid fuel into electrical energy to power devices, while simultaneously operating at low temperatures and producing virtually no greenhouse gases. Since the direct methanol fuel cell performance characteristics are inherently nonlinear and complex, it can be postulated that artificial neural networks represent a marked improvement in performance prediction capabilities. Artificial neural networks have long been used as a tool in predictive modeling. In this work, an artificial neural network is employed to predict the performance of a direct methanol fuel cell under various operating conditions. This work on the experimental analysis of a uniquely designed fuel cell and the computational modeling of a unique algorithm has not been found in prior literature outside of the authors and their affiliations. The fuel cell input variables for the performance analysis consist not only of the methanol concentration, fuel cell temperature, and current density, but also the number of cells and anode flow rate. The addition of the two typically unconventional variables allows for a more distinctive model when compared to prior neural network models. The key performance indicator of our neural network model is the cell voltage, which is an average voltage across the stack and ranges from 0 to 0:8V. Experimental studies were carried out using DMFC stacks custom-fabricated, with a membrane electrode assembly consisting of an additional unique liquid barrier layer to minimize water loss through the cathode side to the atmosphere. To determine the best fit of the model to the experimental cell voltage data, the model is trained using two different second order training algorithms: OWO-Newton and Levenberg-Marquardt (LM). The OWO-Newton algorithm has a topology that is slightly different from the topology of the LM algorithm by the employment of bypass weights. It can be concluded that the application of artificial neural networks can rapidly construct a predictive model of the cell voltage for a wide range of operating conditions with an accuracy of 10−3 to 10−4. The results were comparable with existing literature. The added dimensionality of the number of cells provided insight into scalability where the coefficient of the determination of the results for the two multi-cell stacks using LM algorithm were up to 0:9998. The model was also evaluated with empirical data of a single-cell stack.

Direct methanol fuel cell performance of sulfonated polyimide membranes

2009 ◽  
Vol 194 (2) ◽  
pp. 674-682 ◽  
Author(s):  
Zhaoxia Hu ◽  
Takahiro Ogou ◽  
Makoto Yoshino ◽  
Otoo Yamada ◽  
Hidetoshi Kita ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Direct Methanol Fuel Cell ◽  
Cell Performance ◽  
Fuel Cell Performance ◽  
Sulfonated Polyimide ◽  
Direct Methanol ◽  
Methanol Fuel Cell ◽  
Polyimide Membranes

Study on a Vapor-Feed Air-Breathing Direct Methanol Fuel Cell Assisted by a Catalytic Combustor

2015 ◽  
Vol 12 (1) ◽  
Author(s):  
Wei Yuan ◽  
Hong-Rong Xia ◽  
Jin-Yi Hu ◽  
Zhao-Chun Zhang ◽  
Yong Tang
Keyword(s):  
Fuel Cell ◽  
Direct Methanol Fuel Cell ◽  
Cell Performance ◽  
Catalyst Loading ◽  
High Concentration ◽  
Methanol Vapor ◽  
Air Breathing ◽  
Direct Methanol ◽  
Catalytic Combustor ◽  
Methanol Fuel Cell

Feeding vaporized methanol to the direct methanol fuel cell (DMFC) helps reduce the effects of methanol crossover (MCO) and facilitates the use of high-concentration or neat methanol so as to enhance the energy density of the fuel cell system. This paper reports a novel system design coupling a catalytic combustor with a vapor-feed air-breathing DMFC. The combustor functions as an assistant heat provider to help transform the liquid methanol into vapor phase. The feasibility of this method is experimentally validated. Compared with the traditional electric heating mode, the operation based on this catalytic combustor results in a higher cell performance. Results indicate that the values of methanol concentration and methanol vapor chamber (MVC) temperature both have direct effects on the cell performance, which should be well optimized. As for the operation of the catalytic combustor, it is necessary to optimize the number of capillary wicks and also catalyst loading. In order to fast trigger the combustion reaction, an optimal oxygen feed rate (OFR) must be used. The required amount of oxygen to sustain the reaction can be far lower than that for methanol ignition in the starting stage.

Sign in / Sign up

Export Citation Format

Share Document