The Samsung Huanxin car battery project, China's largest production base, went into operation in Xi'an, capital of Shaanxi province, on Thursday.

The first-stage production base can provide batteries for 40,000 electric vehicles (pure electric EV standards) annually. The project will involve total investment of $600 million by 2020 over several stages and achieve annual sales exceeding $1 billion, according to Pan Yixin, chairman of the board of Huanxin Group.

The project was signed on Jan 22, 2014 by Samsung SDI, Huanxin Group and Xi'an Gaoke Group the parties establishing a joint-venture in June 2014 for the project to produce ESS (energy storage system) batteries.

It is the first project Samsung SDI, world leaders in lithium ion battery technology, has invested in for production of car batteries outside South Korea.

The project began construction on Aug 18, 2014 and was completed within 13 months, which showed "Shaanxi Speed" and "Xi’an Efficiency", said Yue Huafeng, deputy mayor of Xi'an city.

The first stage was completed in April, 2015 and put into trial production, realizing a batch production for batteries in August. Capacity of the project is to produce 3.6 million battery cores annually, Pan said.

From September, the battery production base signed contracts with more than 10 Chinese and foreign vehicle and car manufacturing companies to supply batteries and has begun to supply products.