"Hydrogen" is installed| major car companies to accelerate the layout of hydrogen energy "outlet"
Red Network Moment News April 21 (reporter Long Zhen) hydrogenation for 3 minutes, endurance of 600 kilometers... In recent years, as one of the main technical paths of new energy vehicles, "hydrogen energy vehicles" are bringing people endless imagination space.
During this year's Beijing Winter Olympics, in Yanqing and Zhangjiakou, more than a thousand hydrogen energy buses shuttled between the venues, allowing hydrogen cars to come to the spotlight again.
So, how do hydrogen cars work? How is it different from fuel vehicles and electric vehicles?
What is a hydrogen car
First of all, we need to understand what is a hydrogen energy car, and hydrogen energy car is a car with hydrogen as an energy source. General cars are internal combustion engine combustion diesel or gasoline generated thrust as a power source, and hydrogen energy vehicles include hydrogen internal combustion engine vehicles and hydrogen fuel cell vehicles, of which the former power source is hydrogen combustion in the internal combustion engine energy, the latter makes hydrogen or hydrogen-containing substances react with oxygen in the air in the fuel cell to generate electric push motors, by which the motor pushes the vehicle.
Types of hydrogen vehicles
Hydrogen vehicles are mainly divided into two categories, hydrogen internal combustion engines and hydrogen fuel cell technology.
Hydrogen internal combustion engine
Hydrogen fuel cell technology
How hydrogen internal combustion engine cars work
The principle of hydrogen engine is the same as that of fuel combustion engine, which is a kind of power equipment that releases chemical energy from the reactive gas through combustion and works through gas expansion.
The hydrogen internal combustion engine is not a new concept, it started very early, dating back to the mid-19th century. In 1841, the United Kingdom granted a patent for the first engine working with a hydrogen-oxygen mixture.
Among all the car brands, bmw insists on developing hydrogen internal combustion engine technology. BMW began working on hydrogen fuel power in 1978, demonstrating a hydrogen internal combustion engine car at the 1996 World Hydrogen Energy Conference, followed by a demonstration operation fleet of 750HL modified from its flagship 7 Series at the 2000 Hannover World Expo in Germany.
In 2007, BMW launched the Hydrogen 7, the closest hydrogen combustion engine car to date, to mass production. But the end result we also see, BMW is now turning its energy to the direction of hydrogen fuel cells.
The BMW 7 Series powered by hydrogen fuel
And the hydrogen internal combustion engine has a drawback, that is, hydrogen combustion in the engine, although it will generate water, but it will also produce a certain amount of NOx at high temperatures with the inhaled air. And because hydrogen internal combustion engines are hotter, NOx emissions are more severe than traditional combustion engines.
How hydrogen fuel cell vehicles work
Hydrogen fuel cell technology is currently the mainstream direction of major car companies, the working principle is to send hydrogen to the anode of the fuel cell, under the action of the catalyst, a hydrogen atom is decomposed into 2 hydrogen ions and 2 electrons, hydrogen ions through the proton exchange membrane, combined with oxygen to generate water, electrons can not pass through the exchange membrane, can only pass through the external circuit, forced to produce current.
Theoretically, as long as hydrogen is continuously delivered to the anode and oxygen is delivered to the cathode, electricity can be continuously generated.
How hydrogen is converted into electricity works
Hydrogen fuel cells are good at avoiding the disadvantages of hydrogen internal combustion, such as chemical reactions do not require high temperature, so the product after energy exchange is only water, the energy density is higher, and the energy conversion efficiency is much higher than that of hydrogen internal combustion engines.
The power system of hydrogen fuel cell vehicles is mainly composed of high-pressure hydrogen storage tanks, power batteries, fuel cell stacks, fuel cell boosters and drive electricity.
The main component of the power system of hydrogen fuel cell vehicles
Among them, the fuel cell stack is the most core component of the hydrogen fuel cell vehicle, which supplies the electric engine; the high-pressure hydrogen storage tank provides the fuel, and the power battery pack provides the external power, allowing the car to accelerate, climb and run at high speed. In addition, when the vehicle is taxiing, the energy control unit will drive the motor into a generator, thereby turning part of the car kinetic energy into electrical energy to charge the power battery.
How hydrogen fuel cell vehicles work
Compared with ordinary cars, hydrogen fuel cell vehicles emit only pure water, and only a small amount of hydrogen (2.5 kg) can last about 400 kilometers, and the cost of fuel is much lower than that of internal combustion engine fuels such as gasoline and diesel.
Compared with pure electric vehicles, hydrogen fuel cell vehicles replace lithium batteries with PEMFC battery stacks, as the energy source of electric engines, so that the car has a longer range; at the same time, the charging (inflation) time has changed from 1-2 hours of electric vehicles to 3-5 minutes of hydrogen fuel cell vehicles, which is similar to the time of refueling.
How hydrogen is made
At present, there are still many problems in the promotion and application of hydrogen energy, the first of which is the manufacture of hydrogen.
At present, there are several main methods of industrial hydrogen production: one is to use fossil fuels to produce hydrogen; the second is to extract hydrogen from chemical by-products; the third is to use methanol methane from organisms to produce hydrogen; and the fourth is to use natural energy such as solar energy and wind energy for water electrolysis.
As the infrastructure of hydrogen fuel cell vehicles, the mainland has built more than 130 hydrogen refueling stations, and the number of hydrogen refueling stations in the country will exceed 5,000 by 2035.
Haima Automobile photovoltaic hydrogen production and high-pressure hydrogenation integrated station
In addition, car companies have also begun to lay out hydrogen refueling stations. On December 10, 2021, Haima Automobile's photovoltaic hydrogen production and high-pressure hydrogenation integrated station was officially completed in Haikou, and the water electrolysis hydrogen production capacity in the station was 50 standard squares per hour, which can produce about 107kg of "green hydrogen" per day.
With the promotion of policies and the acceleration of the layout of car companies, hydrogen energy vehicles are expected to speed up.