Lotte Energy Materials is a South Korea–based manufacturer of advanced electronic materials, best known for electrolytic copper foil used as the current collector in lithium‑ion batteries. The company was formerly Iljin Materials and became part of the Lotte Group following its acquisition by Lotte Chemical, after which it was rebranded as Lotte Energy Materials.
Its battery‑grade copper foils are supplied to global cell and electronics manufacturers for applications in electric vehicles, energy storage systems, and consumer devices. The company also provides copper foils for broader electronic and industrial uses. Lotte Energy Materials operates production and R&D in South Korea and internationally, including Malaysia, and continues to expand capacity to support growth in the rechargeable battery supply chain.