Development Status of Hydrogen Energy Vehicles in Japan

The development of hydrogen energy vehicles in Japan is not very optimistic.

Even Toyota is not sure whether hydrogen fuel cells will be popularized in the future. Most automobile companies are engaged in strategic research and trial production to ensure that key technical fields are not backward.

Disadvantages of hydrogen fuel cells

First of all, it is difficult to store and transport hydrogen: because hydrogen molecules are the least molecular structure, it is difficult to ensure that even closed containers are not easy to leak slightly, and the leakage can only be controlled to almost zero, which will not endanger the application. However, the costs involved are enormous.

The cost of pressure vessels is not low. I think the research materials think that the hydrogen pressure tank should be at least 35MPa, and Toyota uses a three-layer structure of 70MPa. In addition to pressure vessels, the regulations of gate valves and pipelines connected with hydrogen tanks are much higher than those of other fuels. The service life is not clear, but the maintenance cost may be much higher.

Second, the cost of platinum metal catalysts increases: Nickel cobalt manganese (NCM) or Nickel cobalt aluminum (NCA) is the main raw material of metal catalysts commonly used in ternary lithium batteries. In fact, the amount of cobalt is very small (about 10%), but now the price of cobalt has skyrocketed. The key reason is that the output of lithium batteries is huge, so even if the cobalt consumption of a single rechargeable battery is small, it can't eat more rechargeable batteries.

Therefore, everyone is studying the orientation of cobalt-free rechargeable batteries scientifically. In the aspect of hydrogen fuel cells, I saw that some graduation papers were also studying the replacement of platinum with metal catalysts. After all, platinum is too expensive, much more expensive than cobalt, or it is not used much at this stage. If hydrogen fuel cells are produced in large quantities, it is not clear that the price of platinum will be higher.

Third, the cost of electricity and energy is also high: for example, the calorific value of automobile gasoline is 47.3MJ/Kg, that of natural gas (methane gas) is 78MJ/Kg, and that of hydrogen is 1.4 1.8 MJ/Kg. At present, the price of gasoline is calculated by 7 yuan, 1kg 9.7 yuan (calculated by the relative density of No.92 gasoline, 0.725Kg/L), and the price of natural gas is calculated by commercial gas. 1 kg is 6.25 yuan (calculated by natural gas 0.72Kg/m3), and the price of hydrogen is 1 kg 40 yuan. According to the specific calorific value, the cost per megajoule of automobile gasoline is 0.2 yuan, the cost per megajoule of natural gas is 0.08 yuan, and the cost per megajoule of hydrogen is 0.28 yuan. ?

The advantages of hydrogen energy are basically only in the fuel cell industry. In other industries, natural gas (CH4) can completely explode hydrogen energy. The production and manufacture of 1 m3 hydrogen must be 6.7-7.3 kWh, and the carbon emission per kWh is about 0.785 kg according to the specification, which means that the carbon emission of 1 m3 hydrogen is about 5.3 kg, while the carbon emission of 1 m3 hydrogen is only 90 g.. Natural gas is a primary energy source, which leads to chemical changes of organic compounds in the whole process and no carbon emission. When ignited, the carbon emission per kilogram is 2.04kg, that is, the carbon emission per 90g of natural gas is 0.18kg.

The calorific value of 90g hydrogen is 12.8MJ, and that of 90g natural gas is 7MJ. ? So the carbon emission of hydrogen is 16 times that of natural gas at the same calorific value? In addition, the temperature of vaporized hydrogen is lower than that of natural gas, and the access time is lower than that of natural gas, which means that the storage and transportation cost of hydrogen is higher than that of natural gas.