DIY methanol fuel cell. DIY fuel cell at home

Description:

Hydrogen fuel cells convert the chemical energy of fuel into electricity, bypassing the ineffective processes of combustion and conversion of thermal energy into mechanical energy, which involve large losses. A hydrogen fuel cell is electrochemical The device directly generates electricity as a result of highly efficient “cold” combustion of fuel. Hydrogen-air proton exchange membrane fuel cell (PEMFC) is one of the most promising fuel technologies elements.

A proton-conducting polymer membrane separates two electrodes - anode and cathode. Each electrode is a carbon plate (matrix) coated with a catalyst. At the anode catalyst, molecular hydrogen dissociates and gives up electrons. Hydrogen cations are conducted through the membrane to the cathode, but electrons are given into the external circuit, since the membrane does not allow electrons to pass through.

At the cathode catalyst, an oxygen molecule combines with an electron (which is supplied from the electrical circuit) and an incoming proton and forms water, which is the only product of the reaction (in the form of vapor and/or liquid).

Membrane-electrode units, which are the key generating element of the energy system, are made from hydrogen fuel cells.

Advantages of hydrogen fuel cells compared to traditional solutions:

– increased specific energy intensity (500 ÷ 1000 Wh/kg),

– extended operating temperature range (-40 0 C / +40 0 C),

– absence of heat spot, noise and vibration,

– reliability at cold start,

– practically unlimited energy storage period (no self-discharge),

– the ability to change the energy intensity of the system by changing the number of fuel cartridges, which provides almost unlimited autonomy,

– the ability to provide almost any reasonable energy intensity of the system by changing the capacity of the hydrogen storage,

– high energy intensity,

– tolerance to impurities in hydrogen,

– long service life,

– environmental friendliness and quiet operation.

Application:

– power supply systems for UAVs,

– portable chargers,

– uninterruptible power supplies,

– Other devices.

Nissan hydrogen fuel cell

Mobile electronics are improving every year, becoming more widespread and accessible: PDAs, laptops, mobile and digital devices, photo frames, etc. All of them are constantly updated with new functions, larger monitors, wireless communications, stronger processors, while decreasing in size . Power technologies, unlike semiconductor technology, are not advancing by leaps and bounds.

The existing batteries and accumulators to power the achievements of the industry are becoming insufficient, so the issue of alternative sources is very acute. Fuel cells are by far the most promising area. The principle of their operation was discovered back in 1839 by William Grove, who generated electricity by changing the electrolysis of water.

Video: Documentary, fuel cells for transport: past, present, future

Fuel cells are of interest to car manufacturers, and spaceship designers are also interested in them. In 1965, they were even tested by America on the Gemini 5 spacecraft launched into space, and later on Apollo. Millions of dollars are still being invested in fuel cell research today, when there are problems associated with environmental pollution and increasing emissions of greenhouse gases generated during the combustion of fossil fuels, the reserves of which are also not endless.

A fuel cell, often called an electrochemical generator, operates in the manner described below.

Being, like accumulators and batteries, a galvanic element, but with the difference that the active substances are stored in it separately. They are supplied to the electrodes as they are used. Natural fuel or any substance obtained from it burns on the negative electrode, which can be gaseous (hydrogen, for example, and carbon monoxide) or liquid, like alcohols. Oxygen usually reacts at the positive electrode.

But the seemingly simple principle of operation is not easy to translate into reality.

DIY fuel cell

Video: DIY hydrogen fuel cell

Unfortunately, we do not have photographs of what this fuel element should look like, we rely on your imagination.

You can make a low-power fuel cell with your own hands even in a school laboratory. You need to stock up on an old gas mask, several pieces of plexiglass, alkali and an aqueous solution of ethyl alcohol (more simply, vodka), which will serve as “fuel” for the fuel cell.

First of all, you need a housing for the fuel cell, which is best made from plexiglass, at least five millimeters thick. The internal partitions (there are five compartments inside) can be made a little thinner - 3 cm. To glue plexiglass, use glue of the following composition: six grams of plexiglass shavings are dissolved in one hundred grams of chloroform or dichloroethane (work is done under a hood).

Now you need to drill a hole in the outer wall, into which you need to insert a glass drain tube with a diameter of 5-6 centimeters through a rubber stopper.

Everyone knows that in the periodic table the most active metals are in the lower left corner, and highly active metalloids are in the upper right corner of the table, i.e. the ability to donate electrons increases from top to bottom and from right to left. Elements that can, under certain conditions, manifest themselves as metals or metalloids are in the center of the table.

Now we pour activated carbon from the gas mask into the second and fourth compartments (between the first partition and the second, as well as the third and fourth), which will act as electrodes. To prevent coal from spilling out through the holes, you can place it in nylon fabric (women's nylon stockings are suitable). IN

The fuel will circulate in the first chamber, and in the fifth there should be an oxygen supplier - air. There will be an electrolyte between the electrodes, and in order to prevent it from leaking into the air chamber, you need to soak it with a solution of paraffin in gasoline (ratio of 2 grams of paraffin to half a glass of gasoline) before filling the fourth chamber with carbon for the air electrolyte. On the layer of coal you need to place (by slightly pressing) copper plates to which the wires are soldered. Through them, the current will be diverted from the electrodes.

All that remains is to charge the element. For this you need vodka, which must be diluted with water 1:1. Then carefully add three hundred to three hundred fifty grams of caustic potassium. For the electrolyte, 70 grams of potassium hydroxide is dissolved in 200 grams of water.

The fuel cell is ready for testing. Now you need to simultaneously pour fuel into the first chamber and electrolyte into the third. A voltmeter connected to the electrodes should show from 07 volts to 0.9. To ensure continuous operation of the element, it is necessary to remove spent fuel (drain into a glass) and add new fuel (through a rubber tube). The feed rate is adjusted by squeezing the tube. This is what the operation of a fuel cell looks like under laboratory conditions, the power of which is understandably low.

Video: Fuel cell or eternal battery at home

To ensure greater power, scientists have been working on this problem for a long time. The active steel in development houses methanol and ethanol fuel cells. But, unfortunately, they have not yet been put into practice.

Why the fuel cell is chosen as an alternative power source

A fuel cell was chosen as an alternative power source, since the end product of hydrogen combustion in it is water. The only problem is finding an inexpensive and efficient way to produce hydrogen. Enormous funds invested in the development of hydrogen generators and fuel cells cannot but bear fruit, so a technological breakthrough and their real use in everyday life is only a matter of time.

Already today the monsters of the automotive industry: General Motors, Honda, Draimler Coyler, Ballard are demonstrating buses and cars that run on fuel cells, the power of which reaches 50 kW. But the problems associated with their safety, reliability, and cost have not yet been resolved. As already mentioned, unlike traditional power sources - batteries and accumulators, in this case the oxidizer and fuel are supplied from the outside, and the fuel cell is only an intermediary in the ongoing reaction of burning fuel and converting the released energy into electricity. “Combustion” occurs only if the element supplies current to the load, like a diesel electric generator, but without a generator and a diesel engine, and also without noise, smoke and overheating. At the same time, the efficiency is much higher, since there are no intermediate mechanisms.

Video: Hydrogen fuel cell car

Great hopes are placed on the use of nanotechnology and nanomaterials, which will help miniaturize fuel cells while increasing their power. There have been reports that ultra-efficient catalysts have been created, as well as designs for fuel cells that do not have membranes. In them, fuel (methane, for example) is supplied to the element along with the oxidizer. Interesting solutions use oxygen dissolved in air as an oxidizer, and organic impurities that accumulate in polluted waters are used as fuel. These are so-called biofuel elements.

Fuel cells, according to experts, may enter the mass market in the coming years.

Mobile electronics are becoming more accessible and widespread every year, if not month. Here you will find laptops, PDAs, digital cameras, mobile phones, and a host of other useful and not so useful devices. And all these devices are constantly acquiring new features, more powerful processors, larger color screens, wireless communications, while at the same time decreasing in size. But, unlike semiconductor technologies, power technologies for this entire mobile menagerie are not progressing by leaps and bounds.

Conventional batteries and rechargeable batteries are becoming clearly insufficient to power the latest advances in the electronics industry for any significant period of time. And without reliable and capacious batteries, the whole point of mobility and wirelessness is lost. So the computer industry is working more and more actively on the problem alternative power sources. And the most promising direction here today is fuel cells.

The basic operating principle of fuel cells was discovered by British scientist Sir William Grove in 1839. He is known as the father of the "fuel cell". William Grove generated electricity by altering to extract hydrogen and oxygen. Having disconnected the battery from the electrolytic cell, Grove was surprised to find that the electrodes began to absorb the released gas and generate current. Opening a process electrochemical "cold" combustion of hydrogen became a significant event in the energy industry, and subsequently such famous electrochemists as Ostwald and Nernst played a major role in the development of the theoretical foundations and practical implementation of fuel cells and predicted a great future for them.

Myself term "fuel cell" appeared later - it was proposed in 1889 by Ludwig Mond and Charles Langer, who were trying to create a device for generating electricity from air and coal gas.

During normal combustion in oxygen, oxidation of organic fuel occurs, and the chemical energy of the fuel is inefficiently converted into thermal energy. But it turned out to be possible to carry out the oxidation reaction, for example, of hydrogen with oxygen, in an electrolyte environment and, in the presence of electrodes, to obtain an electric current. For example, by supplying hydrogen to an electrode located in an alkaline medium, we obtain electrons:

2H2 + 4OH- → 4H2O + 4e-

which, passing through the external circuit, arrive at the opposite electrode, to which oxygen flows and where the reaction takes place: 4e- + O2 + 2H2O → 4OH-

It can be seen that the resulting reaction 2H2 + O2 → H2O is the same as during conventional combustion, but in a fuel cell, or otherwise - in electrochemical generator, the result is electric current with great efficiency and partially heat. Note that fuel cells can also use coal, carbon monoxide, alcohols, hydrazine, and other organic substances as fuel, and air, hydrogen peroxide, chlorine, bromine, nitric acid, etc. as oxidizing agents.

The development of fuel cells continued vigorously both abroad and in Russia, and then in the USSR. Among the scientists who made a great contribution to the study of fuel cells, we note V. Jaco, P. Yablochkov, F. Bacon, E. Bauer, E. Justi, K. Cordesh. In the middle of the last century, a new assault on fuel cell problems began. This is partly due to the emergence of new ideas, materials and technologies as a result of defense research.

One of the scientists who made a major step in the development of fuel cells was P. M. Spiridonov. Hydrogen-oxygen elements of Spiridonov gave a current density of 30 mA/cm2, which was considered a great achievement at that time. In the forties, O. Davtyan created an installation for the electrochemical combustion of generator gas obtained by gasification of coal. For each cubic meter of element volume, Davtyan received 5 kW of power.

It was first solid electrolyte fuel cell. It had high efficiency, but over time the electrolyte became unusable and needed to be changed. Subsequently, Davtyan, in the late fifties, created a powerful installation that drives the tractor. In the same years, the English engineer T. Bacon designed and built a battery of fuel cells with a total power of 6 kW and an efficiency of 80%, running on pure hydrogen and oxygen, but the power-to-weight ratio of the battery turned out to be too small - such elements were unsuitable for practical use and too expensive.

In subsequent years, the time for loners passed. The creators of spacecraft became interested in fuel cells. Since the mid-60s, millions of dollars have been invested in fuel cell research. The work of thousands of scientists and engineers allowed us to reach a new level, and in 1965. fuel cells were tested in the United States on the Gemini 5 spacecraft, and later on the Apollo spacecraft for flights to the Moon and under the Shuttle program.

In the USSR, fuel cells were developed at NPO Kvant, also for use in space. In those years, new materials had already appeared - solid polymer electrolytes based on ion exchange membranes, new types of catalysts, electrodes. Still, the operating current density was small - in the range of 100-200 mA/cm2, and the platinum content on the electrodes was several g/cm2. There were many problems related to durability, stability, and safety.

The next stage of rapid development of fuel cells began in the 90s. last century and continues to this day. It is caused by the need for new efficient energy sources in connection, on the one hand, with the global environmental problem of increasing greenhouse gas emissions from the combustion of fossil fuels and, on the other hand, with the depletion of reserves of such fuel. Since in a fuel cell the final product of hydrogen combustion is water, they are considered the cleanest in terms of environmental impact. The main problem is just finding an effective and inexpensive way to produce hydrogen.

Billions of dollars in financial investments in the development of fuel cells and hydrogen generators should lead to a technological breakthrough and make their use in everyday life a reality: in cells for cell phones, in cars, in power plants. Already, such automotive giants as Ballard, Honda, Daimler Chrysler, and General Motors are demonstrating cars and buses powered by fuel cells with a power of 50 kW. A number of companies have developed demonstration power plants using fuel cells with solid oxide electrolyte with a power of up to 500 kW. But, despite a significant breakthrough in improving the characteristics of fuel cells, many problems related to their cost, reliability, and safety still need to be solved.

In a fuel cell, unlike batteries and accumulators, both fuel and oxidizer are supplied to it from the outside. The fuel cell only mediates the reaction and, under ideal conditions, could operate virtually forever. The beauty of this technology is that the cell actually burns fuel and directly converts the released energy into electricity. When fuel is directly burned, it is oxidized by oxygen, and the heat released is used to perform useful work.

In a fuel cell, as in batteries, the reactions of fuel oxidation and oxygen reduction are spatially separated, and the “combustion” process occurs only if the cell supplies current to the load. It's just like diesel electric generator, only without diesel and generator. And also without smoke, noise, overheating and with much higher efficiency. The latter is explained by the fact that, firstly, there are no intermediate mechanical devices and, secondly, the fuel cell is not a heat engine and, as a result, does not obey Carnot’s law (that is, its efficiency is not determined by the temperature difference).

Oxygen is used as an oxidizing agent in fuel cells. Moreover, since there is enough oxygen in the air, there is no need to worry about the supply of an oxidizing agent. As for fuel, it is hydrogen. So, the reaction takes place in the fuel cell:

2H2 + O2 → 2H2O + electricity + heat.

The result is useful energy and water vapor. The simplest in its structure is proton exchange membrane fuel cell(see Figure 1). It works as follows: hydrogen entering the element is decomposed under the action of a catalyst into electrons and positively charged hydrogen ions H+. Then a special membrane comes into play, playing the role of an electrolyte in a conventional battery. Due to its chemical composition, it allows protons to pass through but retains electrons. Thus, the electrons accumulated on the anode create an excess negative charge, and the hydrogen ions create a positive charge on the cathode (the voltage across the element is about 1V).

To create high power, a fuel cell is assembled from many cells. If you connect an element to a load, electrons will flow through it to the cathode, creating a current and completing the process of oxidation of hydrogen with oxygen. Platinum microparticles deposited on carbon fiber are usually used as a catalyst in such fuel cells. Due to its structure, such a catalyst allows gas and electricity to pass through well. The membrane is usually made from the sulfur-containing polymer Nafion. The thickness of the membrane is tenths of a millimeter. During the reaction, of course, heat is also released, but not so much of it, so the operating temperature is maintained in the region of 40-80°C.

Fig.1. Operating principle of a fuel cell

There are other types of fuel cells, mainly differing in the type of electrolyte used. Almost all of them require hydrogen as fuel, so the logical question arises: where to get it. Of course, it would be possible to use compressed hydrogen from cylinders, but problems immediately arise associated with the transportation and storage of this highly flammable gas under high pressure. Of course, hydrogen can be used in bound form, as in metal hydride batteries. But the task of extracting and transporting it still remains, because the infrastructure for hydrogen refueling does not exist.

However, there is also a solution here - liquid hydrocarbon fuel can be used as a source of hydrogen. For example, ethyl or methyl alcohol. True, this requires a special additional device - a fuel converter, which at high temperatures (for methanol it will be about 240 ° C) converts alcohols into a mixture of gaseous H2 and CO2. But in this case, it’s already more difficult to think about portability - such devices are good to use as stationary or, but for compact mobile equipment you need something less bulky.

And here we come to exactly the device that almost all the largest electronics manufacturers are developing with terrible force - methanol fuel cell(Figure 2).

Fig.2. Operating principle of a methanol fuel cell

The fundamental difference between hydrogen and methanol fuel cells is the catalyst used. The catalyst in a methanol fuel cell allows protons to be removed directly from the alcohol molecule. Thus, the issue with fuel is resolved - methyl alcohol is mass-produced for the chemical industry, it is easy to store and transport, and to charge a methanol fuel cell it is enough to simply replace the fuel cartridge. True, there is one significant disadvantage - methanol is toxic. In addition, the efficiency of a methanol fuel cell is significantly lower than that of a hydrogen one.

Rice. 3. Methanol fuel cell

The most tempting option is to use ethyl alcohol as fuel, since the production and distribution of alcoholic beverages of any composition and strength is well established throughout the globe. However, the efficiency of ethanol fuel cells, unfortunately, is even lower than that of methanol ones.

As has been noted over the many years of development in the fuel cell field, various types of fuel cells have been built. Fuel cells are classified by electrolyte and fuel type.

1. Solid polymer hydrogen-oxygen electrolyte.

2. Solid polymer methanol fuel cells.

3. Alkaline electrolyte cells.

4. Phosphoric acid fuel cells.

5. Fuel elements based on molten carbonates.

6. Solid oxide fuel cells.

Ideally, the efficiency of fuel cells is very high, but in real conditions there are losses associated with nonequilibrium processes, such as: ohmic losses due to the specific conductivity of the electrolyte and electrodes, activation and concentration polarization, and diffusion losses. As a result, part of the energy generated in fuel cells is converted into heat. The efforts of specialists are aimed at reducing these losses.

The main source of ohmic losses, as well as the reason for the high price of fuel cells, are perfluorinated sulfonic cation exchange membranes. The search is now underway for alternative, cheaper proton-conducting polymers. Since the conductivity of these membranes (solid electrolytes) reaches an acceptable value (10 Ohm/cm) only in the presence of water, the gases supplied to the fuel cell must be additionally humidified in a special device, which also increases the cost of the system. Catalytic gas diffusion electrodes mainly use platinum and some other noble metals, and so far no replacement has been found for them. Although the platinum content in fuel cells is several mg/cm2, for large batteries its amount reaches tens of grams.

When designing fuel cells, much attention is paid to the heat removal system, since at high current densities (up to 1A/cm2) the system self-heats. For cooling, water is used circulating in the fuel cell through special channels, and at low powers - air blowing.

So, a modern electrochemical generator system, in addition to the fuel cell battery itself, is “overgrown” with many auxiliary devices, such as: pumps, a compressor for supplying air, injecting hydrogen, a gas humidifier, a cooling unit, a gas leakage monitoring system, a DC-AC converter, a control processor etc. All this leads to the fact that the cost of a fuel cell system in 2004-2005 was 2-3 thousand $/kW. According to experts, fuel cells will become available for use in transport and stationary power plants at a price of $50-100/kW.

To introduce fuel cells into everyday life, along with cheaper components, we must expect new original ideas and approaches. In particular, great hopes are pinned on the use of nanomaterials and nanotechnologies. For example, several companies have recently announced the creation of ultra-efficient catalysts, in particular for oxygen electrodes, based on clusters of nanoparticles from various metals. In addition, there have been reports of membraneless fuel cell designs in which liquid fuel (such as methanol) is fed into the fuel cell along with an oxidizer. Also interesting is the developing concept of biofuel cells operating in polluted waters and consuming dissolved air oxygen as an oxidizer, and organic impurities as fuel.

According to experts, fuel cells will enter the mass market in the coming years. Indeed, one after another, developers overcome technical problems, report successes and present prototypes of fuel cells. For example, Toshiba demonstrated a finished prototype of a methanol fuel cell. It has a size of 22x56x4.5mm and produces a power of about 100mW. One refill of 2 cubes of concentrated (99.5%) methanol is enough for 20 hours of operation of the MP3 player. Toshiba has released a commercial fuel cell to power mobile phones. Again, the same Toshiba demonstrated a cell for powering laptops measuring 275x75x40mm, allowing the computer to operate for 5 hours on a single charge.

Another Japanese company, Fujitsu, is not far behind Toshiba. In 2004, she also introduced an element that operates in a 30% aqueous solution of methanol. This fuel cell operated on one 300 ml charge for 10 hours and produced a power of 15 W.

Casio is developing a fuel cell in which methanol is first converted into a mixture of H2 and CO2 gases in a miniature fuel converter, and then fed into the fuel cell. During the demonstration, the Casio prototype powered a laptop for 20 hours.

Samsung also made its mark in the field of fuel cells - in 2004, it demonstrated its 12 W prototype designed to power a laptop. In general, Samsung plans to use fuel cells primarily in fourth-generation smartphones.

It must be said that Japanese companies generally took a very thorough approach to the development of fuel cells. Back in 2003, companies such as Canon, Casio, Fujitsu, Hitachi, Sanyo, Sharp, Sony and Toshiba joined forces to develop a single fuel cell standard for laptops, mobile phones, PDAs and other electronic devices. American companies, of which there are also many in this market, mostly work under contracts with the military and develop fuel cells for the electrification of American soldiers.

The Germans are not far behind - the company Smart Fuel Cell sells fuel cells to power a mobile office. The device is called Smart Fuel Cell C25, has dimensions of 150x112x65mm and can deliver up to 140 watt-hours per fill. This is enough to power the laptop for approximately 7 hours. Then the cartridge can be replaced and you can continue working. The size of the methanol cartridge is 99x63x27 mm, and it weighs 150g. The system itself weighs 1.1 kg, so it cannot be called completely portable, but it is still a completely complete and convenient device. The company is also developing a fuel module to power professional video cameras.

In general, fuel cells have almost entered the mobile electronics market. Manufacturers still have to solve the last technical problems before starting mass production.

First, it is necessary to resolve the issue of miniaturization of fuel cells. After all, the smaller the fuel cell, the less power it can produce - so new catalysts and electrodes are constantly being developed that make it possible to maximize the working surface with small sizes. This is where the latest developments in the field of nanotechnology and nanomaterials (for example, nanotubes) come in very handy. Again, to miniaturize the piping of elements (fuel and water pumps, cooling and fuel conversion systems), achievements of microelectromechanics are increasingly being used.

The second important problem that needs to be addressed is price. After all, very expensive platinum is used as a catalyst in most fuel cells. Again, some of the manufacturers are trying to make the most of already well-established silicon technologies.

As for other areas of use of fuel cells, fuel cells have already become quite firmly established there, although they have not yet become mainstream either in the energy sector or in transport. Already, many car manufacturers have presented their concept cars powered by fuel cells. Fuel cell buses are running in several cities around the world. Canadian Ballard Power Systems produces a range of stationary generators with a capacity from 1 to 250 kW. At the same time, kilowatt generators are designed to immediately supply one apartment with electricity, heat and hot water.

A fuel cell is a device that efficiently produces heat and direct current through an electrochemical reaction and uses a hydrogen-rich fuel. Its operating principle is similar to that of a battery. Structurally, the fuel cell is represented by an electrolyte. What's so special about it? Unlike batteries, hydrogen fuel cells do not store electrical energy, do not require electricity to recharge, and do not discharge. The cells continue to produce electricity as long as they have a supply of air and fuel.

Peculiarities

The difference between fuel cells and other electricity generators is that they do not burn fuel during operation. Due to this feature, they do not require high-pressure rotors and do not emit loud noise or vibration. Electricity in fuel cells is generated through a silent electrochemical reaction. The chemical energy of the fuel in such devices is converted directly into water, heat and electricity.

Fuel cells are highly efficient and do not produce large amounts of greenhouse gases. The emission product during cell operation is a small amount of water in the form of steam and carbon dioxide, which is not released if pure hydrogen is used as fuel.

History of appearance

In the 1950s and 1960s, NASA's emerging need for energy sources for long-term space missions provoked one of the most critical challenges for fuel cells that existed at that time. Alkaline cells use oxygen and hydrogen as fuel, which are converted through an electrochemical reaction into byproducts useful during space flight - electricity, water and heat.

Fuel cells were first discovered at the beginning of the 19th century - in 1838. At the same time, the first information about their effectiveness appeared.

Work on fuel cells using alkaline electrolytes began in the late 1930s. Cells with nickel-plated electrodes under high pressure were not invented until 1939. During World War II, fuel cells consisting of alkaline cells with a diameter of about 25 centimeters were developed for British submarines.

Interest in them increased in the 1950-80s, characterized by a shortage of petroleum fuel. Countries around the world have begun to address air and environmental pollution issues in an effort to develop environmentally friendly fuel cell production technology is currently undergoing active development.

Principle of operation

Heat and electricity are generated by fuel cells as a result of an electrochemical reaction involving a cathode, anode and an electrolyte.

The cathode and anode are separated by a proton-conducting electrolyte. After oxygen enters the cathode and hydrogen enters the anode, a chemical reaction is started, resulting in heat, current and water.

Dissociates on the anode catalyst, which leads to the loss of electrons. Hydrogen ions enter the cathode through the electrolyte, while electrons pass through the external electrical network and create a direct current, which is used to power the equipment. An oxygen molecule on the cathode catalyst combines with an electron and an incoming proton, ultimately forming water, which is the only product of the reaction.

Types

The choice of a specific type of fuel cell depends on its application. All fuel cells are divided into two main categories - high temperature and low temperature. The latter use pure hydrogen as fuel. Such devices typically require processing of primary fuel into pure hydrogen. The process is carried out using special equipment.

High temperature fuel cells don't need this because they convert fuel at elevated temperatures, eliminating the need for hydrogen infrastructure.

The operating principle of hydrogen fuel cells is based on the conversion of chemical energy into electrical energy without ineffective combustion processes and the transformation of thermal energy into mechanical energy.

General concepts

Hydrogen fuel cells are electrochemical devices that produce electricity through highly efficient "cold" combustion of fuel. There are several types of such devices. The most promising technology is considered to be hydrogen-air fuel cells equipped with a proton exchange membrane PEMFC.

The proton-conducting polymer membrane is designed to separate two electrodes - the cathode and the anode. Each of them is represented by a carbon matrix with a catalyst deposited on it. dissociates on the anode catalyst, donating electrons. Cations are conducted to the cathode through the membrane, but electrons are transferred to the external circuit because the membrane is not designed to transfer electrons.

An oxygen molecule on the cathode catalyst combines with an electron from the electrical circuit and an incoming proton, ultimately forming water, which is the only product of the reaction.

Hydrogen fuel cells are used to manufacture membrane-electrode units, which act as the main generating elements of the energy system.

Advantages of Hydrogen Fuel Cells

Among them are:

Increased specific heat capacity.
Wide operating temperature range.
No vibration, noise or heat stain.
Cold start reliability.
No self-discharge, which ensures long-term energy storage.
Unlimited autonomy thanks to the ability to adjust energy intensity by changing the number of fuel cartridges.
Providing virtually any energy intensity by changing the hydrogen storage capacity.
Long service life.
Quiet and environmentally friendly operation.
High level of energy intensity.
Tolerance to foreign impurities in hydrogen.

Application area

Due to their high efficiency, hydrogen fuel cells are used in various fields:

Portable chargers.
Power supply systems for UAVs.
Uninterruptible power supplies.
Other devices and equipment.

Prospects for hydrogen energy

The widespread use of hydrogen peroxide fuel cells will only be possible after the creation of an effective method for producing hydrogen. New ideas are required to bring the technology into active use, with high hopes placed on the concept of biofuel cells and nanotechnology. Some companies have relatively recently released effective catalysts based on various metals, at the same time information has appeared about the creation of fuel cells without membranes, which has made it possible to significantly reduce the cost of production and simplify the design of such devices. The advantages and characteristics of hydrogen fuel cells do not outweigh their main disadvantage - high cost, especially in comparison with hydrocarbon devices. The creation of one hydrogen power plant requires a minimum of 500 thousand dollars.

How to assemble a hydrogen fuel cell?

You can create a low-power fuel cell yourself in a regular home or school laboratory. The materials used are an old gas mask, pieces of plexiglass, an aqueous solution of ethyl alcohol and alkali.

The body of a hydrogen fuel cell is created with your own hands from plexiglass with a thickness of at least five millimeters. The partitions between the compartments can be thinner - about 3 millimeters. Plexiglas is glued together with a special glue made from chloroform or dichloroethane and plexiglass shavings. All work is carried out only with the hood running.

A hole with a diameter of 5-6 centimeters is drilled in the outer wall of the housing, into which a rubber stopper and a glass drain tube are inserted. Activated carbon from the gas mask is poured into the second and fourth compartments of the fuel cell housing - it will be used as an electrode.

Fuel will circulate in the first chamber, while the fifth is filled with air, from which oxygen will be supplied. The electrolyte, poured between the electrodes, is impregnated with a solution of paraffin and gasoline to prevent it from entering the air chamber. Copper plates with wires soldered to them are placed on the layer of coal, through which the current will be drained.

The assembled hydrogen fuel cell is charged with vodka diluted with water in a 1:1 ratio. Caustic potassium is carefully added to the resulting mixture: 70 grams of potassium dissolve in 200 grams of water.

Before testing a hydrogen fuel cell, fuel is poured into the first chamber and electrolyte into the third. The reading of a voltmeter connected to the electrodes should vary from 0.7 to 0.9 volts. To ensure continuous operation of the element, spent fuel must be removed, and new fuel must be poured through a rubber tube. By squeezing the tube, the fuel supply rate is adjusted. Such hydrogen fuel cells, assembled at home, have little power.

Owners of patent RU 2379795:

The invention relates to direct-acting alcohol fuel cells using solid acid electrolytes and internal reforming catalysts. The technical result of the invention is increased specific power and voltage of the element. According to the invention, a fuel cell includes an anode, a cathode, a solid acid electrolyte, a gas diffusion layer and an internal reforming catalyst. The internal reforming catalyst may be any suitable reformer and is located adjacent to the anode. In this configuration, the heat generated in the exothermic reactions on the catalyst in the fuel cell and the ohmic heating of the fuel cell electrolyte are the driving force for the endothermic fuel reforming reaction converting the alcohol fuel to hydrogen. Any alcohol fuel can be used, such as methanol or ethanol. 5 n. and 20 salary f-ly, 4 ill.

Field of technology

The invention relates to direct alcohol fuel cells using solid acid electrolytes.

State of the art

Alcohols have recently received intense research as potential fuels. Particularly desirable fuels are alcohols such as methanol and ethanol because they have energy densities five to seven times greater than those of standard compressed hydrogen. For example, one liter of methanol is energetically equivalent to 5.2 liters of hydrogen compressed to 320 atm. In addition, one liter of ethanol is energetically equivalent to 7.2 liters of hydrogen compressed to 350 atm. Such alcohols are also desirable because they are easy to handle, store and transport.

Methanol and ethanol have been the subject of much research from an alcohol fuel perspective. Ethanol can be produced by fermenting plants containing sugar and starch. Methanol can be produced by gasification of wood or wood/cereal waste (straw). However, methanol synthesis is more effective. These alcohols are, among other things, renewable resources and are therefore believed to play an important role in both reducing greenhouse gas emissions and reducing dependence on fossil fuels.

Fuel cells have been proposed as devices that convert the chemical energy of such alcohols into electrical energy. In this regard, direct alcohol fuel cells having polymer electrolyte membranes have been subjected to intensive research. Specifically, the research focused on direct methanol fuel cells and direct ethanol fuel cells. However, research on direct ethanol fuel cells has been limited due to the relative difficulty of oxidizing ethanol compared to oxidizing methanol.

Despite these extensive research efforts, the performance of direct alcohol fuel cells remains unsatisfactory, mainly due to the kinetic limitations imposed by the electrode catalysts. For example, typical direct methanol fuel cells have a power density of approximately 50 mW/cm 2 . Higher power densities have been achieved, such as 335 mW/cm2, but only under extremely harsh conditions (Nafion®, 130°C, 5 atm oxygen and 1 M methanol for a flow rate of 2 cc/min at a pressure of 1.8 atm). Similarly, a direct ethanol fuel cell has a power density of 110 mW/cm2 under similar extremely harsh conditions (Nafion® - silica, 140°C, anode 4 atm, oxygen 5.5 atm). Accordingly, there is a need for direct alcohol fuel cells having high power densities in the absence of such extreme conditions.

Summary of the Invention

The present invention relates to alcohol fuel cells containing solid acid electrolytes and using an internal reforming catalyst. A fuel cell generally includes an anode, a cathode, a solid acid electrolyte, and an internal reformer. The reformer ensures the reforming of alcohol fuel to produce hydrogen. The driving force for the reforming reaction is the heat generated during exothermic reactions in the fuel cell.

The use of solid acid electrolytes in the fuel cell makes it possible to place the reformer directly adjacent to the anode. This was not previously thought possible due to the elevated temperatures required for known reforming materials to function effectively and the heat sensitivity of typical polymer electrolyte membranes. However, compared to conventional polymer electrolyte membranes, solid acid electrolytes can withstand much higher temperatures, making it possible to locate the reformer adjacent to the anode and therefore close to the electrolyte. In this configuration, waste heat generated by the electrolyte is absorbed by the reformer and serves as the driving force for the endothermic reforming reaction.

Brief description of drawings

These and other features and advantages of the present invention will be better understood by reference to the following detailed description taken in conjunction with the accompanying drawings, in which:

Figure 1 is a schematic illustration of a fuel cell according to one embodiment of the present invention;

Figure 2 is a graphical comparison of the curves between power density and cell voltage for fuel cells obtained in accordance with Examples 1 and 2 and Comparative Example 1;

Figure 3 is a graphical comparison of the power density-cell voltage curves for fuel cells obtained in accordance with Examples 3, 4 and 5 and Comparative Example 2; And

Figure 4 is a graphical comparison of the power density versus cell voltage curves for fuel cells obtained in accordance with Comparative Examples 2 and 3.

Detailed Description of the Invention

The present invention relates to direct alcohol fuel cells containing solid acid electrolytes and using an internal reforming catalyst in physical contact with a membrane electrode assembly (MEA) designed to reform the alcohol fuel to produce hydrogen. As noted above, the performance of fuel cells, which convert chemical energy in alcohols directly into electrical power, remains unsatisfactory due to kinetic limitations imposed by the fuel cell electrode catalysts. However, it is well known that these kinetic limitations are significantly reduced when hydrogen fuel is used. Accordingly, the present invention utilizes a reforming catalyst or reformer designed to reform an alcohol fuel to produce hydrogen, thereby reducing or eliminating the kinetic limitations associated with the alcohol fuel. Alcohol fuels are steam reformed according to the following reaction examples:

Methanol to hydrogen: CH 3 OH + H 2 O → 3H 2 + CO 2 ;

Ethanol to hydrogen: C 2 H 5 OH+3H 2 O→6H 2 +2CO 2.

However, the reforming reaction is highly endothermic. Therefore, to obtain the driving force for the reforming reaction, the reformer must be heated. The amount of heat required is typically approximately 59 kJ per mole of methanol (equivalent to burning approximately 0.25 moles of hydrogen) and approximately 190 kJ per mole of ethanol (equivalent to burning approximately 0.78 moles of hydrogen).

As a result of the passage of electric current during operation of fuel cells, waste heat is generated, the effective removal of which is problematic. However, the generation of this waste heat makes placing the reformer directly adjacent to the fuel cell a natural choice. This configuration allows hydrogen to be supplied from the reformer to the fuel cell and cools the fuel cell, and allows the fuel cell to heat the reformer and provide the driving force for reactions therein. This configuration is used in molten carbonate fuel cells and for methane reforming reactions occurring at approximately 650°C. However, alcohol reforming reactions generally occur at temperatures ranging from about 200° C. to about 350° C., and no suitable fuel cell using alcohol reforming has yet been developed.

The present invention relates to such a fuel cell using alcohol reforming. As illustrated in FIGURE 1, a fuel cell 10 in accordance with the present invention generally includes a first current collector/gas diffusion layer 12, an anode 12a, a second current collector/gas diffusion layer 14, a cathode 14a, an electrolyte 16, and an internal reforming catalyst 18. Internal reforming catalyst 18 located adjacent to the anode 12a. More specifically, the reforming catalyst 18 is positioned between the first gas diffusion layer 12 and the anode 12a. Any known suitable reforming catalyst 18 may be used. Non-limiting examples of suitable reforming catalysts include Cu-Zn-Al oxide mixtures, Cu-Co-Zn-Al oxide mixtures, and Cu-Zn-Al-Zr oxide mixtures.

Any alcohol fuel such as methanol, ethanol and propanol can be used. In addition, dimethyl ether can be used as fuel.

Historically, this configuration was not considered possible for alcohol fuel cells due to the endothermic nature of the reforming reaction and the sensitivity of the electrolyte to heat. Typical alcohol fuel cells use polymer electrolyte membranes that cannot withstand the heat required to provide the driving force for the reforming catalyst. However, the electrolytes used in the fuel cells of the present invention contain solid acid electrolytes, such as those described in U.S. Patent No. 6,468,684 entitled PROTON CONDUCTING MEMBRANE USING A SOLID ACID, the entire contents of which are incorporated herein by reference, and at the same time Pending U.S. Patent Application Serial No. 10/139043 entitled PROTON CONDUCTING MEMBRANE USING A SOLID ACID, the entire contents of which are also incorporated herein by reference. One non-limiting example of a solid acid suitable for use as an electrolyte in the present invention is CsH 2 PO 4 . The solid acid electrolytes used in the fuel cells of the present invention can withstand much higher temperatures, making it possible to place the reforming catalyst directly adjacent to the anode. In addition, the endothermic reforming reaction consumes the heat generated by the exothermic reactions in the fuel cell, forming a thermally balanced system.

These solid acids are used in their superprotic phases and act as proton-conducting membranes in the temperature range from about 100°C to about 350°C. The upper end of this temperature range is ideal for reforming methanol. To provide heat generation sufficient to provide the driving force for the reforming reaction, and to ensure proton conductivity of the solid acid electrolyte, the fuel cell of the present invention is preferably operated at temperatures ranging from about 100°C to about 500°C. However, it is more preferable to operate the fuel cell at temperatures ranging from about 200°C to about 350°C. In addition to significantly improving the performance of alcohol fuel cells, the relatively high operating temperatures of the alcohol fuel cells of the invention may enable the replacement of expensive metal catalysts such as Pt/Ru and Pt on the anode and cathode, respectively, with less expensive catalyst materials.

The following examples and comparative examples illustrate the superior performance characteristics of the alcohol fuel cells of the invention. However, these examples are presented for purposes of illustration only and should not be construed as limiting the invention to these examples.

Example 1: Methanol Fuel Cell

13 mg/cm2 Pt/Ru was used as an anodic electrocatalyst. Cu (30% wt.) - Zn (20% wt.) - Al was used as an internal reforming catalyst. 15 mg/cm 2 Pt was used as a cathode electrocatalyst. A CsH 2 PO 4 membrane with a thickness of 160 μm was used as an electrolyte. Mixtures of methanol and water converted into steam were fed into the anode space at a flow rate of 100 μL/min. 30% humidified oxygen was supplied to the cathode at a flow rate of 50 cm 3 /min (standard temperature and pressure). The methanol:water ratio was 25:75. The element temperature was set to 260°C.

Example 2: Ethanol Fuel Cell

13 mg/cm2 Pt/Ru was used as an anodic electrocatalyst. Cu (30% wt.) - Zn (20% wt.) - Al was used as an internal reforming catalyst. 15 mg/cm 2 Pt was used as a cathode electrocatalyst. A CsH 2 PO 4 membrane with a thickness of 160 μm was used as an electrolyte. Mixtures of ethanol and water converted into steam were fed into the anode space at a flow rate of 100 μL/min. 30% humidified oxygen was supplied to the cathode at a flow rate of 50 cm 3 /min (standard temperature and pressure). The ethanol:water ratio was 15:85. The element temperature was set to 260°C.

Comparative Example 1 - Fuel Cell Using Pure H 2

13 mg/cm2 Pt/Ru was used as an anodic electrocatalyst. 15 mg/cm 2 Pt was used as a cathode electrocatalyst. A CsH 2 PO 4 membrane with a thickness of 160 μm was used as an electrolyte. 3% humidified hydrogen was supplied to the anode space at a flow rate of 100 μL/min. 30% humidified oxygen was supplied to the cathode at a flow rate of 50 cm 3 /min (standard temperature and pressure). The element temperature was set to 260°C.

Figure 2 shows the curves of the relationship between specific power and cell voltage for examples 1 and 2 and comparative example 1. As shown, for the methanol fuel cell (example 1) a peak power density of 69 mW/cm 2 is achieved, for the ethanol (example 2) fuel cell cell achieves a peak power density of 53 mW/cm2, and for a hydrogen fuel cell (Comparative Example 1) a peak power density of 80 is achieved

mW/cm2. These results show that the fuel cells obtained in accordance with Example 1 and Comparative Example 1 are very similar, indicating that the methanol fuel cell having a reformer exhibits performance almost as good as that of a hydrogen fuel cell. which is a significant improvement. However, as demonstrated in the following examples and comparative examples, by reducing the thickness of the electrolyte, an additional increase in power density is achieved.

The fuel cell was produced by slurry deposition of CsH 2 PO 4 onto a porous stainless steel support, which served as both a gas diffusion layer and a current collector. The cathode electrocatalyst layer was first deposited onto the gas diffusion layer and then compacted before deposition of the electrolyte layer. After this, a layer of anode electrocatalyst was deposited, followed by placement of a second gas diffusion electrode as the final layer of the structure.

A mixture of CsH 2 PO 4 , Pt (50 atomic wt %) Ru, Pt (40 wt %) - Ru (20 wt %) supported on C (40 wt %) and naphthalene was used as the anode electrode. The ratio of components in the mixture of CsH 2 PO 4:Pt-Ru:Pt-Ru-C: naphthalene was 3:3:1:0.5 (wt). The mixture was used in a total amount of 50 mg. The Pt and Ru loadings were 5.6 mg/cm2 and 2.9 mg/cm2, respectively. The area of the anode electrode was 1.74 cm 2 .

A mixture of CsH 2 PO 4 , Pt, Pt (50 wt.%) deposited on C (50 wt. %) and naphthalene was used as a cathode electrode. The ratio of components in the mixture of CsH 2 PO 4:Pt:Pt-C: naphthalene was 3:3:1:1 (wt). The mixture was used in a total amount of 50 mg. Pt loadings were 7.7 mg/cm 2 . The cathode area was 2.3-2.9 cm 1 .

CuO (30 wt. %) - ZnO (20 wt. %) - Al 2 O 3 was used as a reforming catalyst, that is, CuO (31 mol. %) - ZnO (16 mol. %) - Al 2 O 3 . The reforming catalyst was prepared by a co-precipitation method using a solution of copper, zinc and aluminum nitrate (total metal concentration was 1 mol/L) and an aqueous solution of sodium carbonates (1.1 mol/L). The precipitate was washed with deionized water, filtered and dried in air at 120°C for 12 hours. The dried powder in an amount of 1 g was lightly pressed to a thickness of 3.1 mm and a diameter of 15.6 mm, and then calcined at 350°C for 2 hours.

A CsH 2 PO 4 membrane with a thickness of 47 μm was used as an electrolyte.

A methanol-water solution (43% vol. or 37% wt. or 25% mol. or 1.85 M methanol) was fed through a glass evaporator (200°C) at a flow rate of 135 μL/min. The element temperature was set to 260°C.

The fuel cell was prepared in accordance with Example 3 above, except that not a methanol-water mixture, but an ethanol-water mixture (36% vol. or 31% wt.) was fed through the evaporator (200°C) at a flow rate of 114 μl/min . or 15 mol.%, or 0.98 M ethanol).

The fuel cell was prepared in accordance with Example 3 above, except that at a flow rate of 100 μL/min, instead of the methanol-water mixture, vodka (Absolut Vodka, Sweden) (40% vol. or 34% wt., or 17% mol) was supplied . ethanol).

Comparative example 2

The fuel cell was prepared in accordance with Example 3 above, except that instead of a methanol-water mixture, dried hydrogen was used in an amount of 100 standard cubic centimeters per minute, humidified with hot water (70°C).

Comparative example 3

A fuel cell was prepared in accordance with Example 3 above, except that no reforming catalyst was used and the cell temperature was set to 240°C.

Comparative example 4

A fuel cell was prepared in accordance with Comparative Example 2, except that the cell temperature was set to 240°C.

Figure 3 shows the power density versus cell voltage curves for Examples 3, 4 and 5 and Comparative Example 2. As shown, the methanol fuel cell (Example 3) achieved a peak power density of 224 mW/cm2, which represents a significant increase power density compared to the fuel cell obtained in accordance with Example 1 and having a much thicker electrolyte. This methanol fuel cell also demonstrates a dramatic improvement in performance compared to methanol fuel cells that do not use an internal reformer, as better demonstrated in Figure 4. The ethanol fuel cell (Example 4) also demonstrates increased power density and cell voltage compared to the ethanol fuel cell. having a thicker electrolyte membrane (example 2). However, the methanol fuel cell (Example 3) has been shown to perform better than the ethanol fuel cell (Example 4). For the vodka fuel cell (example 5), power densities comparable to those of an ethanol fuel cell are achieved. As shown in Figure 3, the methanol fuel cell (Example 3) exhibits performance characteristics approximately as good as that of the hydrogen fuel cell (Comparative Example 2).

Figure 4 shows power density versus cell voltage curves for Comparative Examples 3 and 4. As shown, the reformerless methanol fuel cell (Comparative Example 3) achieves power densities that are significantly lower than those achieved for hydrogen fuel cell (Comparative Example 4). In addition, Figures 2, 3 and 4 show that, compared to a methanol fuel cell without a reformer (Comparative Example 3), significantly higher power densities are achieved for methanol fuel cells with reformers (Examples 1 and 3).

The foregoing description has been presented to introduce the currently preferred embodiments of the invention. Those skilled in the relevant art and technology to which this invention relates will understand that changes and modifications may be made to the described embodiments without significantly deviating from the principles, scope and spirit of the present invention. Accordingly, the foregoing description should not be taken to refer only to the specific embodiments described, but rather should be understood to be consistent with and to support the following claims, which contain the fullest and most objective scope of the invention.

1. A fuel cell including: an anode electrocatalytic layer, a cathode electrocatalytic layer, an electrolyte layer containing a solid acid, a gas diffusion layer, and an internal reforming catalyst located adjacent to the anode electrocatalytic layer, such that the internal reforming catalyst is located between the anode electrocatalytic layer and the gas diffusion layer. and is in physical contact with the anode electrocatalytic layer.

2. The fuel cell according to claim 1, wherein the solid acid electrolyte contains CsH 2 PO 4 .

3. The fuel cell of claim 1, wherein the reforming catalyst is selected from the group consisting of Cu-Zn-Al oxide mixtures, Cu-Co-Zn-Al oxide mixtures and Cu-Zn-Al-Zr oxide mixtures.

4. A method of operating a fuel cell, including:

fuel supply; and operating the fuel cell at a temperature ranging from about 100°C to about 500°C.

5. The method according to claim 4, where the fuel is alcohol.

6. The method according to claim 4, where the fuel is selected from the group consisting of methanol, ethanol, propanol and dimethyl ether.

7. The method of claim 4, wherein the fuel cell is operated at a temperature in the range of about 200°C to about 350°C.

8. The method of claim 4, wherein the reforming catalyst is selected from the group consisting of Cu-Zn-Al oxide mixtures, Cu-Co-Zn-Al oxide mixtures and Cu-Zn-Al-Zr oxide mixtures.

9. The method according to claim 4, where the electrolyte contains a solid acid.

10. The method according to claim 9, where the solid acid contains CsH 2 PO 4 .

11. A method of operating a fuel cell, including:
formation of an anodic electrocatalytic layer;
formation of a cathode electrocatalytic layer;
forming an electrolyte layer containing a solid acid;
formation of a gas diffusion layer and
forming an internal reforming catalyst adjacent the anodic electrocatalytic layer such that the internal reforming catalyst is located between the anodic electrocatalytic layer and the gas diffusion layer and is in physical contact with the anodic electrocatalytic layer;
fuel supply; and operating the fuel cell at a temperature ranging from about 200°C to about 350°C.

12. The method according to claim 11, where the fuel is alcohol.

13. The method according to claim 11, where the fuel is selected from the group consisting of methanol, ethanol, propanol and dimethyl ether.

14. The method of claim 11, wherein the reforming catalyst is selected from the group consisting of a mixture of Cu-Zn-Al oxides, mixtures of Cu-Co-Zn-Al oxides and mixtures of Cu-Zn-Al-Zr oxides.

15. The method according to claim 11, where the electrolyte contains a solid acid.

16. The method according to claim 15, where the solid acid contains CsH 2 PO 4 .

17. A method of operating a fuel cell, including:
formation of an anodic electrocatalytic layer;
formation of a cathode electrocatalytic layer;
forming an electrolyte layer containing a solid acid;
formation of a gas diffusion layer and
forming an internal reforming catalyst adjacent the anodic electrocatalytic layer such that the internal reforming catalyst is located between the anodic electrocatalytic layer and the gas diffusion layer and is in physical contact with the anodic electrocatalytic layer;
supply of alcohol fuel; and operating the fuel cell at a temperature ranging from about 100°C to about 500°C.

18. The method according to claim 17, wherein the fuel is selected from the group consisting of methanol, ethanol, propanol and dimethyl ether.

19. The method of claim 17, wherein the fuel cell is operated at a temperature ranging from about 200°C to about 350°C.

20. The method of claim 17, wherein the reforming catalyst is selected from the group consisting of Cu-Zn-Al oxide mixtures, Cu-Co-Zn-Al oxide mixtures and Cu-Zn-Al-Zr oxide mixtures.

21. The method according to claim 17, where the solid acid electrolyte contains CsH 2 PO 4 .

22. A method of operating a fuel cell, including:
formation of an anodic electrocatalytic layer;
formation of a cathode electrocatalytic layer;
forming an electrolyte layer containing a solid acid;
formation of a gas diffusion layer and
forming an internal reforming catalyst adjacent the anodic electrocatalytic layer such that the internal reforming catalyst is located between the anodic electrocatalytic layer and the gas diffusion layer and is in physical contact with the anodic electrocatalytic layer;
supply of alcohol fuel; and operating the fuel cell at a temperature ranging from about 200°C to about 350°C.

The invention relates to direct-acting alcohol fuel cells using solid acid electrolytes and internal reforming catalysts