Methanol Fuel Cell
Modeling Environmental and Performance Differences in Miniaturized Micro Direct Methanol Fuel Cells
Interest in the use of micro direct methanol fuel cells in applications with low power needs has been growing since the technology was first developed, and the many different devices and scenarios in which such fuel cells would be of enormous benefit continues to drive research in the area. Direct experimental observation has been conducted on many fronts in an effort to ascertain optimum operating environments and levels of internal elements within the micro direct methanol fuel cell system — such as fuel concentration and rate of delivery — yielding higher outputs and/or longer operational periods for individual and stacked micro direct methanol fuel cells. In this review of current literature on the subject, several such experimental studies are utilized to develop a more comprehensive and multi-faceted view of the design and operational characteristics of the micro direct methanol fuel cell. This review essentially finds that operational temperature and fuel rates are the most influential aspects of the micro direct methanol fuel cell in terms of performance in power output and duration as well as in operational efficiency.
As the number of electricity-dependent technological devices increases and size generally decreases (at least to a point), the need to develop innovative new power sources to be used in or in conjunction with these devices becomes more pressing. Micro direct methanol fuel cells have been shown to be one effective means of addressing this issue; though dependent on a fuel source in a way that a standard battery is not, in proper conditions and with proper design characteristics these fuel cells can provide power for much longer and are completely self-starting, requiring no additional energy input to begin generation (Mench et al. 2001; Lu et al. 2003). These fuel cells are also exponentially smaller than current battery technologies, and though this does limit their power generation capacity it increases their portability and the multitude of applications to which they are suited (Lu et al. 2003). Design techniques utilizing and even creating micro direct methanol fuel cells continue to evolve and develop, creating better understandings of the interacting forces that influence the performance of these micro direct methanol fuel cells. As the technology continues to grow more powerful through innovative cell design and stacking, smaller fuel cells and cell arrangements are able to deliver more power, creating even greater portability and expanding applicability (Lu et al. 2003; Lim et al. 2006; Kamitani et al. 2008).
Area term, cm2
channel height, micrometers
channel width, micrometers
low flow channel length, cm
Review of Current Design and Environmental Research
Though temperature has a major effect on the performance of micro direct methanol fuel cells, it is not generally something that can be easily controlled in practical applications, and thus much research has focused on improving the efficiency of micro direct methanol fuel cells at room temperature. Silicon micro structures for these fuels cells have drawn increasing attention, with experimental research showing that the reduction of the flow rate of methanol in room temperature micro direct methanol fuel cells can greatly improve fuel efficiency, though at the cost of actual power density (Kamitani et al. 2008). Reducing the fuel cell area also played a role in this experiment; reducing the size of the fuel cell surface area to 0.3cm2, the researchers were able to achieve a maximum power output o 12.5 mW cm-2 at a fuel rate of 5.52 microliters per minute-1, at an efficiency of 14.1% (Kamitani et al. 2008). Efficiency becomes 20.1% when the fuel rate is slowed to less than 2 microliters over the same time period, with a less extreme but still observable drop in power density (Kamitani et al. 2008).
Silicon was also a material of interest in an experiment that set out to design a micro direct methanol fuel cell that was specifically meant to be used in portable devices. Using a microelectromechnical technique, fuel delivery channels were etched into the surface of silicon wafers to create individual fuel cells capable of producing up to 50mW/cm2 at T. 60, though this power output was reduced to 16mW/cm2 at room temperature (Lu et al. 2003). This was achieved with a channel only 750W and 400H, and power output remained consistent despite tests using 2M, 4M, and 8M methanol solutions as fuels (Lu et al. 2003). This shows that temperature has a much higher influence on performance than fuel solution or rate.
A more recent and in many ways more innovative use of silicon materials, in combination with others, shows potential to further increase the efficacy and efficiency of micro direct methanol fuel cells. By utilizing high-aspect-ratio carbon nanotubes as fuel delivery and reaction area structures for either the cathode or anode end of a micro direct methanol fuel cell, the reaction area and thus the efficiency of the fuel cell can be greatly increased (Wu et al. 2008). Though this conclusion has yet to be borne out by direct observational evidence, initial experimentation has shown that these nanotubes can be controlled in their growth to produce consistent and effective fuel channels ranging from 100H 10 150H, 80W to 100W, and only 3L-5L. (Wu et al. 2008). This network of micro fuel channels would allow for far greater control of fuel flow and will also increase the exposure of the fuel to the fuel cell (and vice versa), increasing fuel efficiency and ultimately energy production, as the researchers predict with careful addendums (Wu et al. 2008).
None of the current research into these increasingly smaller and more productive micro direct methanol fuel cells would be possible, of course, were it not for foundational work that first developed and described this emerging technology. The essential quality of the micro direct methanol fuel cell design is that it is a pumpless and totally energy-independent system; as long as a fuel supply is maintained the cell will operate through gravitational forces, capillary action, and natural buoyancy and air movement (Mench et al. 2001). The fact that it requires no purposeful energy to operate is key to the continued interest in these fuel cells.
It is this feature that makes micro direct methanol fuel cells so attractive in very small applications, and that allows for the ever-decreasing size of the fuel cells themselves. The creation of micro direct methanol fuel cells on printed circuitry boards has even been achieved, with fairly encouraging results; though temperatures were at 80C, improving performance vastly over room temperature performance according to previous research, the fact that stacked eight cell system was able to produce 180mW/cm2 with channels only 200W and a fuel of 2M methanol shows a high efficiency and energy output per the amount of fuel consumed (Lim et al. 2006). Utilizing microtechnologies to further control the flow rate and exposure of fuel in micro direct methanol fuel cells has increasing benefits in fuel efficiency and in ultimate energy output, and it is expected that a similar system operating at room temperature, though undoubtedly reduced in its efficiency, would show greater energy output than many other devices with similar fuel consumption rates (Lim et al. 2006).
As the capabilities to produce smaller channels for fuel delivery increase, fuel efficiency in micro direct methanol fuel cells is also expected to rise. The ability to control fuel flow in these microstructures is essential to increasing efficiency, and it cannot be easily achieved through mechanical movement. The alteration of the fuel delivery system and the environment in which the micro direct methanol fuel cells operate through design will lead to greater levels of efficiency.
Kamitani, a. Morishita, S.; Kotaki, H.; Arscott, S. (2008). “Miniaturized microDMFC using silicon microsystems techniques: performances at low fuel flow rates.” Journal of micromechanics and microengineering 18.
Lim, S.; Kim, S.; Kim, H.; Ahn, J; Han, H.; Shul, Y. (2006). “Effect of operation parameters on performance of micro direct methanol fuel cell fabricated on printed circuit board.” Journal of power sources 161, pp. 27-33.
Lu, G.; Wang, C. Yen, T.: Zhnag, X. (2003). “Development and characterization of a silicon-based micro direct methanol fuel cell.” Electrochimica Acta 49, pp. 821 — 828.
Mench, M.; Wang, Z.; Bhatia, K.; Wnag, C. (2001). “Design of a micro direct methanol fuel cell.” Proceedings of the IMECE’01 International Mechanical Engineering Congress and Exposition (IMECE) New York, New York USA November 11-16, 2001.
Wu, Y.; Tseng, F.; Tsai, C.; Chieng, C. (2008). “Micro and Nano Structured Reaction Device for Micro DMFC.” Proceedings of the 3rd IEEE Int. Conf. On Nano/Micro Engineered and Molecular Systems January 6-9, 2008, Sanya, China, pp. 816-9.
Get Professional Assignment Help Cheaply
Are you busy and do not have time to handle your assignment? Are you scared that your paper will not make the grade? Do you have responsibilities that may hinder you from turning in your assignment on time? Are you tired and can barely handle your assignment? Are your grades inconsistent?
Whichever your reason is, it is valid! You can get professional academic help from our service at affordable rates. We have a team of professional academic writers who can handle all your assignments.
Why Choose Our Academic Writing Service?
- Plagiarism free papers
- Timely delivery
- Any deadline
- Skilled, Experienced Native English Writers
- Subject-relevant academic writer
- Adherence to paper instructions
- Ability to tackle bulk assignments
- Reasonable prices
- 24/7 Customer Support
- Get superb grades consistently
Online Academic Help With Different Subjects
Students barely have time to read. We got you! Have your literature essay or book review written without having the hassle of reading the book. You can get your literature paper custom-written for you by our literature specialists.
Do you struggle with finance? No need to torture yourself if finance is not your cup of tea. You can order your finance paper from our academic writing service and get 100% original work from competent finance experts.
While psychology may be an interesting subject, you may lack sufficient time to handle your assignments. Don’t despair; by using our academic writing service, you can be assured of perfect grades. Moreover, your grades will be consistent.
Engineering is quite a demanding subject. Students face a lot of pressure and barely have enough time to do what they love to do. Our academic writing service got you covered! Our engineering specialists follow the paper instructions and ensure timely delivery of the paper.
In the nursing course, you may have difficulties with literature reviews, annotated bibliographies, critical essays, and other assignments. Our nursing assignment writers will offer you professional nursing paper help at low prices.
Truth be told, sociology papers can be quite exhausting. Our academic writing service relieves you of fatigue, pressure, and stress. You can relax and have peace of mind as our academic writers handle your sociology assignment.
We take pride in having some of the best business writers in the industry. Our business writers have a lot of experience in the field. They are reliable, and you can be assured of a high-grade paper. They are able to handle business papers of any subject, length, deadline, and difficulty!
We boast of having some of the most experienced statistics experts in the industry. Our statistics experts have diverse skills, expertise, and knowledge to handle any kind of assignment. They have access to all kinds of software to get your assignment done.
Writing a law essay may prove to be an insurmountable obstacle, especially when you need to know the peculiarities of the legislative framework. Take advantage of our top-notch law specialists and get superb grades and 100% satisfaction.
What discipline/subjects do you deal in?
We have highlighted some of the most popular subjects we handle above. Those are just a tip of the iceberg. We deal in all academic disciplines since our writers are as diverse. They have been drawn from across all disciplines, and orders are assigned to those writers believed to be the best in the field. In a nutshell, there is no task we cannot handle; all you need to do is place your order with us. As long as your instructions are clear, just trust we shall deliver irrespective of the discipline.
Are your writers competent enough to handle my paper?
Our essay writers are graduates with bachelor's, masters, Ph.D., and doctorate degrees in various subjects. The minimum requirement to be an essay writer with our essay writing service is to have a college degree. All our academic writers have a minimum of two years of academic writing. We have a stringent recruitment process to ensure that we get only the most competent essay writers in the industry. We also ensure that the writers are handsomely compensated for their value. The majority of our writers are native English speakers. As such, the fluency of language and grammar is impeccable.
What if I don’t like the paper?
There is a very low likelihood that you won’t like the paper.
- When assigning your order, we match the paper’s discipline with the writer’s field/specialization. Since all our writers are graduates, we match the paper’s subject with the field the writer studied. For instance, if it’s a nursing paper, only a nursing graduate and writer will handle it. Furthermore, all our writers have academic writing experience and top-notch research skills.
- We have a quality assurance that reviews the paper before it gets to you. As such, we ensure that you get a paper that meets the required standard and will most definitely make the grade.
In the event that you don’t like your paper:
- The writer will revise the paper up to your pleasing. You have unlimited revisions. You simply need to highlight what specifically you don’t like about the paper, and the writer will make the amendments. The paper will be revised until you are satisfied. Revisions are free of charge
- We will have a different writer write the paper from scratch.
- Last resort, if the above does not work, we will refund your money.
Will the professor find out I didn’t write the paper myself?
Not at all. All papers are written from scratch. There is no way your tutor or instructor will realize that you did not write the paper yourself. In fact, we recommend using our assignment help services for consistent results.
What if the paper is plagiarized?
We check all papers for plagiarism before we submit them. We use powerful plagiarism checking software such as SafeAssign, LopesWrite, and Turnitin. We also upload the plagiarism report so that you can review it. We understand that plagiarism is academic suicide. We would not take the risk of submitting plagiarized work and jeopardize your academic journey. Furthermore, we do not sell or use prewritten papers, and each paper is written from scratch.
When will I get my paper?
You determine when you get the paper by setting the deadline when placing the order. All papers are delivered within the deadline. We are well aware that we operate in a time-sensitive industry. As such, we have laid out strategies to ensure that the client receives the paper on time and they never miss the deadline. We understand that papers that are submitted late have some points deducted. We do not want you to miss any points due to late submission. We work on beating deadlines by huge margins in order to ensure that you have ample time to review the paper before you submit it.
Will anyone find out that I used your services?
We have a privacy and confidentiality policy that guides our work. We NEVER share any customer information with third parties. Noone will ever know that you used our assignment help services. It’s only between you and us. We are bound by our policies to protect the customer’s identity and information. All your information, such as your names, phone number, email, order information, and so on, are protected. We have robust security systems that ensure that your data is protected. Hacking our systems is close to impossible, and it has never happened.
How our Assignment Help Service Works
1. Place an order
You fill all the paper instructions in the order form. Make sure you include all the helpful materials so that our academic writers can deliver the perfect paper. It will also help to eliminate unnecessary revisions.
2. Pay for the order
Proceed to pay for the paper so that it can be assigned to one of our expert academic writers. The paper subject is matched with the writer’s area of specialization.
3. Track the progress
You communicate with the writer and know about the progress of the paper. The client can ask the writer for drafts of the paper. The client can upload extra material and include additional instructions from the lecturer. Receive a paper.
4. Download the paper
The paper is sent to your email and uploaded to your personal account. You also get a plagiarism report attached to your paper.
PLACE THIS ORDER OR A SIMILAR ORDER WITH US TODAY AND GET A PERFECT SCORE!!!