Methanol fuel cells introduction (part 2)
1 Introduction
To maintain the energy density of PEMFC, to avoid following the reorganization of the external power attenuation; also because the process takes the temperature of the environment, improving sanitation will increase the temperature conversion of methanol into hydrogen and oxygen. Therefore, proper control of temperature and chemical dose concentrations of hydrogen and oxygen can be expected. the steam reforming or restructuring of the self-heating temperature can be as low as 200-300 ℃. With external restructuring as an added bonus, the reclassification of gas can be CO oxidation, reducing CO problems and reduce the amount of catalyst, but CO poisoning can also use the cell anti-high temperature fuel. Latitude X1 battery XPS M2010 battery
As the restructuring of methanol micro fuel cell operating temperature to 200-300 ℃, and current problems of the start time of the MFRC and the beginning of the temperature, micro-MFRC For faster startup, usually installed in the combustion catalyst to accelerate the cycle reformer temperature re-start. Both the DMFC MFRC or join the mini in the rechargeable battery to meet the sudden demand for power can also be a hybrid fuel cell / rechargeable ways to reduce fuel cell power.
2, the development of prototypes Casio MFRC
Figure 8 for the Casio in November 2006 show a prototype re-methanol fuel cell, demonstrating the system can lead the digital camera. Prototype is Reformers (reformer), the main body of fuel cell (battery) and two cans of fuel (fuel cartridge) with a compact, fuel lines were installed at the bottom. The composition of other devices, including two hydraulic pumps for the main power to the battery of methanol, a liquid flow sensor for measuring the flow of methanol, on / off valve switch used to control the supply of methanol, air pump to provide air and hydrogen, the two different valve air flow control, two sensors for measuring the flow of air as an auxiliary device. As seen in the prototype, the control circuit is not integrated DC / DC circuit and control circuit in the circuit of Figure 8, it is not displayed. Studio 15 battery Studio 17 battery
(1) Casio prototype structure. The system uses 60% of the mass concentration of methanol as fuel. liquid methanol by two fuel pumps from two 8mL box (diameter 18mm, length 10mm) transported to the reformer, while sensors monitor the flow of liquid. The liquid pump is a Casio and Fraunhofer IZM (a German research organization) developed jointly. Reformer way through the steam reforming of hydrogen produced from methanol. The hydrogen fuel cell result is sent to management or burning in the reformer to ensure that when the catalyst needed to start the temperature. For this reason, a different stream on a per channel on / off valve control traffic. Vostro 1720 battery
In addition to the fuel cell air supply main air pump air into the reformer must be used to remove CO accessories also supply hydrogen to the combustion air is promote the reforming catalyst reaction rate. Straight from the pump into the air to the fuel cell main body, without needing valves. In the reformer channels in each air flow sensors are installed and the different types of valves, so that you can precisely control the air flow. The electricity produced by the fuel cell, then by the DC / DC converter circuit to provide a voltage capable of driving the digital camera. When the fuel cell is like subjects of the four batteries with a demonstration of the way when driving digital cameras, Casio claims the battery can drive the 20 laptops. To achieve commercialization in 2008, the company plans to upgrade the samples of fuel cell prototype will be available for sale. 6Y270 75UYF
(2) Casio important features of several prototypes. Included in the latest prototype Nov. 29 launch of e-penetration (EO) pump. In the maintenance of high pressure compressed 0.5cc unit in the state, this device accurately the distribution of methanol fuel. It consists of NANO technology Fu-sion made of materials produced. Casio successful experience MFRC also includes other key elements such as thermal reformer to extract hydrogen from methanol, and the main body of fuel cells, etc., see Figure 9. The reference to the so-called “EO pump is a small pump, which was formed by the electric permeability material, this material is a silicone dielectric as, when in contact with liquid may produce potential. When his time take over power, its internal flow of liquid will produce. Regardless of the size of size, it can be attributed to the liquid state at high pressure and do not use the motor drive, the most important thing is it works without noise and eliminate problems such as vibration etc.. Casio with its patented materials technology company Nano Fusion permeable (1mm in diameter, 1 mm thick) developed this combination of liquid fuel pumps, mainly used in devices Mobile MFRC. Casio has solved the problems intrinsic EO pump, such as electro generated magnetic material changes due to the collision, such as liquid vapor bubbles generated by electrolysis when the assembly problem. Finally, the EO pump may be concentrated in containers 0.5cc, and even in the 100 kPa atmospheric pressure 90μL/min can maintain the flow. G5266 HD438 KD186
Another important feature is the main use of the principle of steam reformer, methanol and heated to 280 ℃ and extract hydrogen. The structure of Figure 10. In fact, the reformer through a number of improvements, it is currently indicated for solving the insulation start time is too long and too many other issues CO and Casio claimed in 2007 for laptops will be shipped samples reformer. The internal structure, the original principal reformer of two glass substrates, and their use of vacuum insulation, the inner surface of the substrate covered with a layer of gold film to minimize heat dissipation. According to reports, the work of the reformer under the surface temperature is 40 ℃ or above 20 ℃ ambient temperature. Reformer consists of three channels, one channel for the combustion of hydrogen to form methanol and hydrogen to provide the weight of the heat reaction channel reform, fuel and water vapor in the reaction here , eliminating co-channel for the removal of CO by-product. Inspiron 630m battery Inspiron 6400 battery
3 Ultracell25
From 2005 to launch a Ultracell MFRC, and asserts that its energy density is twice as common lithium-ion batteries in about 40 ounces, the size of the battery completely original and graph paper. The technology through UltraCell fuel waste can be used to perform “hot swap” and reuse, to ensure continuous supply. MFRC UltraCell originally developed for military purposes, XX90 model, which provides 45 watts of electricity. Commercial use ultracell25 published in 2006, it can be used in commercial devices, industrial and mobile, the military version of its corresponding XX25. Figure 11 is launched Ultracell XX25 for military MFRC product, it is said to produce equipment for feeding continuously for 72 hours. Inspiron 640m battery Inspiron 700m battery
Third, the comparison of several fuel cell
Several others, including the merger of carbonate fuel cell FC (MCFC), Solid Oxide FC (SOFC), phosphoric acid FC (PAFC), which will also be used to produce electricity and heat. MCFC usually natural gas as fuel. SOFC with hydrogen or carbon compounds, H2 as fuel. MCFC and SOFC working at high temperature (> 650 ℃ ℃ and 800-1000), SOFC can ensure maximum efficiency of power (44% -50%), and symbiosis (co-generation) model to more than 80% . In addition, the polymer electrolyte membrane FC (PEMFC) are often used to power vehicles can also be used for stationary power generation. To avoid the dumping of hazardous substances, PEMFC requires pure H2 and input in the reaction process can not produce CO2. They work at low temperature can provide 35% -40% of the conversion efficiency. Most vehicles fuel cell using PEM, while also a small part in the solid state fuel cell market by 70% -80%. In the long term, MCFC and SOFC are expected to occupy the large size of the market in solid fuel cell. SOFC current share of 15% of this segment of the market share of 20%. The annual world production of thousands of CF, 80% for fixed and mobile devices, and the rest for fuel cell vehicle demonstration project. Inspiron 710m battery Inspiron 8500 battery
If the cost of H2 fuel cells and significantly reduced CO2 emissions while limiting the introduction and enforcement of rules, then FC can be in the next 10 years will be significant market growth (market share 2050-30%). Distribution of potential growth lays CF depends on the materials list rules, which depend on electronic equipment and natural gas prices. SOFC and MCFC fuel gas as a major in 2050, it will be a 5% share of global market share of fuel cells.