The extended-range technology has changed from the "backward technology" of the past to "fragrant and sweet".
According to the latest statistics, the sales growth rate of extended-range vehicles is almost close to 170%, far exceeding the overall growth rate of new energy vehicles.
And many car companies are also making efforts to extend the range, millions of luxury cars look up to U8 using range extender technology, Changan, Wenjie, Leap, Nezha, Deep Blue and other brands, there are also extended-range models on the market, Xiaomi, Geely also spread the news, will develop extended-range models.
The extended-range model, simply put, adds an engine to the electric car, but this engine does not directly drive the wheels, but is only used to generate electricity to extend the range of the electric vehicle. The range extender models on the market all use gasoline internal combustion engines as range extenders, and the highest thermal efficiency is the range extender of Wenjie, which is about 41%. And many people are puzzled that the thermal efficiency of diesel engines is much higher than that of gasoline engines, why no car companies use diesel engines as range extenders?
The working thermal efficiency of diesel engines can usually reach 36% 41%, and even more than 50%. Weichai has released a completely new engine, this engine body structure has 5109% thermal efficiency, a new record. The compression ratio of diesel engine is much higher than that of gasoline engine, the compression ratio of gasoline engine is generally 8-12, and the compression ratio of diesel engine is generally 16-25.
At the same time, in terms of the gap between the fuel itself, diesel itself has a higher number of carbon molecules, so the calorific value is also higher than that of gasoline. It stands to reason that if you use a diesel engine as a range extender, fuel consumption will be lower, as long as you generate electricity in the highest thermal efficiency range, just like a diesel generator, but why don't car companies use a diesel internal combustion engine as a range extender?
Personally, I think it's mainly because of these four reasons:
The first and biggest reason is the NVH control issue. In fact, there are trucks equipped with diesel range extenders in Macau and other regions, but diesel range extenders are only suitable for commercial vehicles, not very suitable for passenger cars, mainly because of NVH.
If you think about it, the range extender model, in the case of low and medium speed, are all pure electric, in the case of using gasoline range extender, the engine intervention has made many car owners feel abrupt, then if the diesel engine is used, the experience is very bad, the diesel engine because of the compression ratio and design reasons, noise and vibration are greater, it is difficult to press down.
The second reason is that the diesel engine is large in size and weight, and the space left for the motor and battery is not sufficient.
The third reason is that the after-treatment of diesel engines is more troublesome, and the exhaust gas processor must be used to meet the requirements of environmental protection, although some gasoline engines also have to be GPF, but not all models, and the treatment system should be simpler.
The fourth reason is that diesel is a strategic resource, so in many cases, civilian people will give concessions to industrial use, so many gas stations often have a shortage of diesel, while gasoline is different, coupled with the oil quality of domestic diesel, even if there is a diesel extended range passenger car, the use experience is relatively collapsed.
Based on the above reasons, diesel range extender passenger cars, there is currently no car company development, for a long time in the future, it is estimated that there will be no car company development, but in the field of commercial vehicles, diesel range extender trucks, buses, may appear in the future.