China's battery electric vehicles lead the world: achievements in technology system architecture and technological breakthroughs

Developing new energy vehicles has been a worldwide consensus, and developing new energy vehicles characterized by pure electric drive has been China's national strategy. After more than 20 years of high-quality development of China's electric vehicles (EVs), a technological R & D layout of “Three Verticals and Three Horizontals” has been created, and technological advantages have been accumulated. As a result, China's new energy vehicle market has ranked first in the world since 2015. To systematically solve the key problems of battery electric vehicles (BEVs) such as “driving range anxiety, long battery charging time, and driving safety hazards”, China took the lead in putting forward a “system engineering-based technology system architecture for BEVs” and clarifying its connotation. This paper analyzes the research status and progress of the three core components of this architecture, namely, “BEV platform, charging/swapping station, and real-time operation monitoring platform”, and their key technological points. The three major demonstration projects of the 2008 Beijing Olympic Games, the 2022 Beijing Winter Olympics, and the intelligent and connected autonomous battery electric bus project are discussed to specify the applications of BEVs in China. The key research directions for upgrading BEV technologies remain to be further improving the vehicle-level all-climate environmental adaptability and all-day safety of BEVs, systematically solving the charging problem of BEVs and improving their application convenience, and safeguarding safety with early warning and implementing active/passive safety protection for the whole life cycle of power batteries on the basis of BEVs' operation big data. BEVs have acquired new technological features such as intelligent and networked technology empowerment, extensive integration of control-by-wire systems, a platform of chassis hardware, and modularization of functional software.