The Germans say the internal combustion engine is doomed? The Japanese disagree

Not long ago, Volkswagen Group, which is still shrouded in the shadow of the emissions scandal, launched the "Together 2025" strategy, indicating that electric vehicles will be the main product in the future. At the same time, some German experts and government officials also believe that if Germany wants to achieve its established environmental protection goals by 2030, it must ban the sale of internal combustion engines in the country. For a time, the Germans who once invented the car seemed to have sentenced our favorite internal combustion engine to "suspended death". Is the internal combustion engine really hopeless? Obviously, the Japanese, who are more stubborn than the Germans, do not think so.

● Denso's 2025 plan 

The year 2025 has been very popular recently, with not only "Made in China 2025" and Volkswagen's "TOGETHER- Strategy 2025", but also the Japanese auto parts giant DENSO recently released a development strategy called ECO VISION 2025. When talking about how to improve the environmental protection level of vehicles, DENSO said that it will reduce the carbon dioxide emissions of internal combustion engines to half of the 2012 level by 2025 through technical efforts. How does DENSO plan to achieve this goal?

- Improved combustion efficiency: ultra-lean combustion

How to improve fuel efficiency? In simple terms, the first thing is to completely burn all the fuel injected each time, but this is just a good wish and is impossible to achieve in reality. Therefore, people have proposed the technical concept of lean combustion. Through lean combustion technology, the thermal efficiency of the internal combustion engine can be improved while reducing the emission of harmful gases.

However, for the existing engine technology structure, ultra-lean combustion will bring many problems, one of the more obvious problems is ignition difficulty. For this reason, Denso is developing a matching ignition technology. Everyone should be familiar with Denso brand spark plugs, and Denso does have strong technical strength in ignition technology. The relevant person in charge said that more than half of the development of ultra-lean combustion has been completed, and I believe we are very likely to see mass production of this technology in 2025.

- Improved exhaust gas purification efficiency: improved catalyst

At present, there are two main factors that affect the efficiency and effect of exhaust gas purification: the speed at which the exhaust gas flows through the catalyst and the temperature of the catalyst. In Denso's view, the current three-way catalytic converter structure design needs further improvement. If the exhaust gas stays in contact with the catalyst for an uneven or too fast time, it will be difficult to improve the efficiency. In addition, when the vehicle has just started and the catalyst has not reached the optimal operating temperature, it will also lead to poor treatment of harmful exhaust gas.

Denso engineers optimized the internal structure of the catalyst to control the flow rate of exhaust gas inside, so that the exhaust gas and the catalyst have sufficient contact time and contact area; when the car is cold, Denso hopes to preheat the catalyst by electric heating so that it reaches the working temperature as soon as possible. Through these two methods, the exhaust gas purification efficiency can be effectively improved, and these technologies have passed the internal tests of Denso and achieved satisfactory results.

- Energy Regeneration: Utilizing Exhaust Heat

We all know that the exhaust temperature of the engine is usually 500-600℃, so it contains considerable heat energy, but usually this energy is wasted with the exhaust gas. Denso is planning to add an electric heat conversion device to the back end of the exhaust treatment system to convert heat energy into electrical energy for use. In addition, the Japanese are also thinking about developing a device to store heat energy for "warming up" the engine when it starts, so that the engine can quickly heat up to the operating temperature.

Toyota : Continuously challenging higher thermal efficiency 

Toyota Motors, which belongs to the same Toyota Group as Denso, is also obsessed with improving the thermal efficiency of internal combustion engines, and the two sides will have a lot of cooperation in this regard. As an OEM, Toyota not only needs to carry out technical development, but also needs to apply various technical structures to mass-produced vehicle products. At the same time, like Denso, Toyota also believes that the potential of internal combustion engines is far from reaching its limit. Not long ago, they announced that they would challenge the 50% thermal efficiency of gasoline engines, and also regarded ultra-lean combustion as the key to success. At the same time, Toyota is also considering adding HCCI (homogeneous premixed compression ignition) technology to gasoline engines, that is, to make ultra-high compression ratio gasoline engines compression ignite like diesel engines.

● Other Japanese brands 

Similar to Toyota, other Japanese car brands are also optimistic about improving the thermal efficiency of internal combustion engines. Mazda, with its unique personality, will try technologies such as a compression ratio of up to 18:1 and lean compression ignition on the second-generation Skyactiv gasoline engine to further improve the engine's fuel efficiency; and Honda's 1.5T engine, code-named L15B, on the tenth-generation Civic, one of its masterpieces of restarting the turbocharged route, has become the king of thermal efficiency of turbocharged gasoline engines as soon as it was launched.

Summarize:

Regarding the future technology route, automobile companies at both ends of the earth have different views, which is normal. Whether it is promoting electric technology or tapping the potential of internal combustion engines, everyone's goal is to make future transportation more environmentally friendly. Of course, the technology route of a company is often closely related to its own interests, but no matter what, it can make the world a better place. Wouldn't it be better to have more choices? Of course, I prefer to vote for the internal combustion engine.