SK Innovation, the holding company for energy businesses of SK Group, said on Friday that it has won the car battery-related patent lawsuit which LG Chem filed in 2012.

The two electric vehicle battery makers have clashed over patents on the inorganic material-coated separator, a key part of large to midsize rechargeable batteries. Seoul Central District Court’s ruling said, “LG Chem’s patent rights for the porous structure of the active layer coating the separator is different from SK Innovation’s inorganic material-coated separator technology.”

This is the third patent infringement lawsuit that SK Innovation has won against LG Chem following the legal victory at the Korean Intellectual Property Tribunal and Patent Court of Korea, the company said.

This lawsuit showed that the patent battle has been nothing but a war of attrition between Korean firms dragging each other down.

This could have caused Korean companies to relinquish their footholds in the EV battery market, where becoming dominant is an overarching priority, industry watchers said.

Riding on the momentum gained from the successful legal challenges over its EV technology, SK Innovation is set to accelerate its advance into the EV battery business as well as the “laser-induced breakdown spectroscopy,” or LiBS, business.

SK Innovation succeeded in commercial production of LiBS for the first time in Korea, and the third time worldwide in 2005. The company added it will aim to become the No. 1 EV battery maker in China with Beijing BESK Technology, a joint venture firm between SK Innovation and China-based BAIC Group, which started operations last January.