SK Innovation Co., a South Korean refining-to-battery conglomerate, is pushing for its third battery plant in Hungary, people familiar with the issue said Monday.

SK Innovation has begun a process of selecting subcontractors for the construction of the proposed plant, they said.

SK Innovation denied that the selection process has begun, saying no decision has been made in regard to the third Hungarian plant.

"We have just concluded that there is a need for further investments to prepare for an increase in car battery demand in Europe," the company said in a statement.

Currently, SK Innovation runs a plant with an annual capacity of 7.5 gigawatt-hours (GWh) in the northwestern Hungarian city of Komarom.

SK Innovation has also been working to complete its second plant with a capacity of 9.8 GWh, next to the first plant, by 2022.

Komarom is home to assembly lines of German carmaker Audi and is not far from a plant of another German automaker, Daimler AG, which owns Mercedes-Benz.

The EV battery market has been on a roll as global automakers race to go electric due to tightened regulations on greenhouse gas emissions, which scientists say are to blame for global warming.

SK Innovation is South Korea's top oil refiner, but it has been moving into the electric vehicle battery business since 2008 as part of efforts to find new revenue sources. (Yonhap)