The central government is continuing its support of the sector. In late September, the State Council gave orders that local governments must not restrict the sales or use of new-energy cars.

That same month, it issued a document that aims to improve battery charging networks and infrastructure. An inadequate number of charging stations is seen as a major hurdle to the sales of new-energy vehicles in China.

The sector is expected to gain momentum further as the Central Committee of the Communist Party of China suggested writing into China's 13th Five-Year Plan (2016-2020) wording to boost technological innovations in the manufacturing of new-energy vehicles and the promotion of their use.

PwC estimates the sales of new-energy vehicles in China will rocket to 1.4 million units by 2020, about 20 times the number of sales in 2014, and to about 3.75 million units by 2025.

Yang Cheng contributed to this story.