Fuel cell vehicle (FCV)
Fuel cell vehicles refer to a new type of vehicle that uses fuel cells to directly convert the chemical energy in the fuel into electrical energy to achieve power driving. Fuel cell vehicles convert chemical energy into electrical energy through the chemical reaction of fuel. Among them, hydrogen is the best material for fuel cells, but hydrogen fuel cells have many problems in terms of hydrogen source, storage, and safety.
Fuel cell vehicles have the following advantages: ①Zero emission or near zero emission, green and environmental protection. A fuel cell vehicle is essentially a zero-emission vehicle. The fuel cell has no combustion process. If pure hydrogen is used as fuel, the hydrogen and oxygen are combined through electrochemical methods, and the product is clean water; Using other hydrogen-rich organic compounds to produce hydrogen using on-board reformers as fuel for fuel cells, the product may have a small amount of CO2 in addition to water, but its emissions are much less than that of internal combustion engines, and there are no other pollutant emissions (such as Nitrogen oxides, sulfur oxides, hydrocarbons or particulates) issues, close to zero emissions. ②High energy conversion efficiency, saving energy. The energy conversion efficiency of fuel cells is extremely high. The fuel cell has no mechanical components such as pistons or turbines and intermediate links, does not undergo a thermal engine process, and is not restricted by the thermal cycle (Carnot cycle), so the energy conversion efficiency is high, and the chemical energy conversion efficiency of the fuel cell can theoretically reach 100%, the actual efficiency has reached 60%~80%, which is 2~3 times the thermal efficiency of ordinary internal combustion engines (the efficiency of gasoline engine and diesel engine vehicles are 16%~18% and 22%~24% respectively). ③The fuel is diversified and the energy consumption structure is optimized. The hydrogen fuel used in fuel cells comes from a wide range of sources. ④Electric vehicles with long driving range and better performance than other batteries. The use of fuel cell power generation system as the energy source overcomes the shortcomings of pure electric vehicles with short driving range, and its long-distance driving capability and power are close to traditional vehicles. ⑤Stable operation and low noise. The fuel cell is a static energy conversion device. It has no moving parts other than the air compressor and cooling system. Therefore, compared with the internal combustion engine car, it gets rid of the roar of the engine and has less noise and vibration during operation.
The industry generally believes that hydrogen fuel cell technology is the best alternative to internal combustion engine technology and represents the future development direction of automobiles. However, fuel cells still have the following shortcomings, which restrict the development of fuel cell vehicles: ① There are technical difficulties in obtaining pure hydrogen fuel economically and without pollution. In nature, a large amount of hydrogen can be stored in water. Although it is inexhaustible, it is more expensive to directly use thermal decomposition or electrolysis to produce hydrogen from water. ② There are still a lot of technical problems in the supply of fuel for hydrogen fuel cell vehicles. Generally, hydrogen energy is stored and transported in three states: High-pressure gas, liquid, and hydride forms. The hydrogen stored in commonly used compressed gas tanks can only be used for fuel cell vehicles to drive 150km. The driving range is too short and not as good as battery-powered vehicles. In addition, hydrogen is the smallest molecule, and it is easy to cause leakage, which requires a high level of safe storage of hydrogen. ③Platinum, the catalyst metal used in hydrogen fuel cells, is expensive. To produce hydrogen fuel cells on a large scale, metallic platinum is the bottleneck, and there is no cost reduction effect after large-scale production. On the contrary, the more demand, the more expensive. The structure of a hydrogen fuel cell vehicle is shown in Figure 1.