Heekyong YangJoyce Lee 3 minute read The logo of SK Innovation is seen in front of its headquarters in Seoul, South Korea, February 3, 2017. REUTERS/Kim Hong-Ji SEOUL, Aug 4 (Reuters) - SK Innovation Co Ltd (096770.KS), the owner of South Korea's top refiner SK Energy, said on Wednesday its expects refining margins to gradually improve in the second half as COVID-19 retreats and demand rebounds, and confirmed plans to make its battery business a stand-alone unit. The company posted an operating profit of 506 billion won ($441 million) in the April-June quarter, compared with an operating lo...