The first electric car was on the road as early as 1990. Although some well-known car manufacturers have launched their own pure electric concept cars in recent years, this has not shortened the distance between electric cars and real life. The reason is the research and development of electric vehicles is not just as simple as replacing the traditional engine with an electric motor, but a huge research topic. There are many problems such as battery capacity, storage capacity, stability, etc. for automotive batteries alone. In addition, replacing traditional engines with electric motors Later, body design, traditional systems, and electrical systems will have disruptive changes. To solve this series of problems, automobile manufacturers need to have strong R & D capabilities. (Center sentence). What does this text mean? ['The bottleneck of electric vehicle research and development is the problem of batteries.', 'It will take time for electric vehicles to be widely used in real life.', 'Electric vehicles have become a new direction for research and development in the automotive industry.', 'The development process of electric vehicles depends on the research and development strength of manufacturers.']