Since Karl Benz produced the world’s first internal combustion engine car in 1886, the rapid development of the automobile industry has greatly changed people’s lifestyles and improved people’s quality of life. Cars have become an indispensable and important means of transportation for human society. In addition, the development of the automobile industry has brought people a lot of employment opportunities and promoted economic development. The advancement of automobile technology has also greatly stimulated the development of a country’s machinery, electronics, materials, molds and many other fields. It can be said that the appearance of cars has changed the face of the entire world.
In recent years, with the increase in national income, China’s auto production and sales have also increased rapidly. In 2016, China’s auto production and sales were 29.119 million and 28.028 million, a year-on-year increase of 14.5% and 14.9%. Among them, passenger vehicle production and sales were 24.421 million and 24.377 million, an increase of 15.5% and 149,000 year-on-year; the production and sales of commercial vehicles were 3.698 million and 3.651 million, an increase of 8.0% and 5.8% year-on-year. In addition, China’s car ownership has shown a blowout growth. The average annual growth in the five years from 2012 to 2017 reached 14 million. According to statistics from the Traffic Management Bureau of the Ministry of Public Security, as of the end of March 2017, China’s automobile ownership reached 200 million. Figure 1 shows the statistics of China’s car ownership from 2010 to 2017.
The rapid development of the automobile industry has also brought about many problems such as energy crisis and environmental pollution. In 2015, China’s oil imports surpassed the United States and became the world’s largest oil importer. The annual import scale exceeded 340 million tons, an increase of nearly 1.5 times compared with 10 years ago. Affected by the international situation and oil supply, oil prices have fluctuated and changed. So far, there have been three oil crises, which have severely affected the world and the economies of various countries. As the automobile industry is the main consumption area of oil, the output of oil in the future will seriously affect the development of traditional fuel vehicles. In addition, the exhaust emissions from fuel vehicles cause serious pollution to the environment. According to the “Annual Report on China’s Motor Vehicle Environmental Management (2017)” released by the Ministry of Environmental Protection, the national motor vehicle emissions in 2016 were 44.725 million tons.
Among them, automobiles are the main contributor to the total pollutant emissions, their emissions of carbon monoxide and nitrogen and hydrogen compounds exceed 80%, and nitrogen oxides and particulate matter exceed 90%. In recent years, severe smog weather has repeatedly occurred in major cities, and the exhaust emissions of fuel vehicles have become the main source of pollution, affecting people’s lives, as shown in Figure 2.
In the face of increasingly severe energy and environmental crises, vigorously developing new energy vehicles and realizing the transformation of transportation energy have become an important way to realize the sustainable development of the automotive industry. After the exploration period of new energy vehicle technology, the mainstream technology has gradually become clear. The electrification of vehicle power and the development of new energy vehicles are the general trend, and consensus has also been reached internationally.
According to the “New Energy Vehicle Production Access Management Rules” of the National Development and Reform Commission in 2007, and the 2009 “New Energy Vehicle Production Enterprise and Product Access Management Rules” of the Ministry of Industry and Information Technology define a new energy vehicle as a vehicle that uses unconventional vehicle fuel as a power source (Or use conventional vehicle fuels and adopt new on-board power devices), integrates advanced technologies in vehicle power control and driving, and forms a vehicle with advanced technical principles, new technologies and new structures.
According to the definition of the document, new energy vehicles include pure electric vehicles, hybrid vehicles, fuel cell electric vehicles, hydrogen engine vehicles, and other new energy vehicles (such as college energy storage, dimethyl ether, etc.) vehicles. In 2012, the State Council’s “Energy-saving and New Energy Automobile Industry Development Plan (2012-2020)” provided a clearer definition of new energy vehicles. At present, China’s new energy vehicles refer to vehicles that adopt new power systems and rely entirely or mainly on new energy sources. Mainly include: Battery Electric Vehicle (BEV), Plug-in Hybrid Electric Vehicle (PHEV), Fuel Cell Vehicles (FCV), and low-energy vehicles such as hybrid vehicles with internal combustion engines as the main power are defined as energy-saving vehicles .