HONG KONG/SEOUL, March 30 (Reuters) - South Korea’s SK IE Technology (SKIET) will begin its initial public offering (IPO) process Wednesday as it aims to raise at least $1 billion, according to two sources with direct knowledge of the matter. The company received preliminary approval Tuesday for the IPO from the Korea Exchange after lodging its application in December. Official filings will be made Wednesday to start the deal, the sources said who could not be named as the information has not yet been made public. SK IET’s parent SK Innovation Co Ltd declined to comment. SK Innovation owns 90% of SKIET, according to the company’s regulatory filing. SKIET develops separators, a key component in lithium-ion batteries. (Reporting by Scott Murdoch in Hong Kong and Heekyong Yang in Seoul, editing by Louise Heavens)