LOTTE Energy Materials (CEO Kim Yeon-seop) is set to secure leadership in the copper foil industry by completing the development of next-generation copper foil, a key future growth driver.

On the 27th, LOTTE Energy Materials announced the completion of the development of nickel-plated foil for all-solid-state batteries. Nickel-plated foil is a next-generation material with nickel plating on both sides of electrolytic copper foil, characterized by excellent electrical conductivity and strong resistance to corrosion, making it an ideal electrode current collector for sulfide-based all-solid-state batteries.

The customer-tailored nickel-plated foil developed by LOTTE Energy Materials can adjust the nickel thickness and copper foil strength according to customer requirements. Additionally, the nickel surface treatment enhances adhesion to active materials and maintains its original properties and functions without corrosion or discoloration due to chemical reactions, offering high corrosion resistance.

While current-level copper foil can be used for lithium-ion batteries, sulfide-based all-solid-state batteries require materials like SUS (stainless steel), nickel foil, or nickel-plated foil due to copper foil corrosion caused by sulfur. However, SUS and nickel foil are costly and lack price competitiveness, making nickel-plated foil, which involves plating both sides of existing copper foil, a promising material for sulfide-based solid electrolyte batteries.

The number of companies capable of manufacturing nickel-plated foil is very limited, and LOTTE Energy Materials has secured a competitive edge by optimizing the nickel-plated foil for all-solid-state battery processes through early collaboration with domestic battery companies. A significant achievement is overcoming the corrosion of copper foil caused by sulfur and addressing economic feasibility, which are major barriers to entry for sulfide-based solid electrolytes.

LOTTE Energy Materials is currently conducting sample evaluations of nickel-plated foil tailored to the processes and form factors of major domestic customers. Additionally, the company is conducting various nickel surface treatment studies to secure adhesion to active materials and plans to communicate with the market separately once it reaches the order stage.

Meanwhile, LOTTE Energy Materials has begun assessing the business feasibility of composite materials for batteries following inquiries from major domestic and international customers. Recently, the company has held technical meetings with leading composite copper foil companies in China and other major domestic and international firms to analyze customer requirements and market conditions from multiple angles.

Composite Copper Foil is manufactured by depositing and plating copper on both sides of polymer films such as PET and PP. This method reduces copper usage compared to traditional copper foil, providing cost competitiveness and weight reduction. However, products used in electric vehicles require high stability and advanced technology, presenting a barrier to entry in the industry.

The background of the customer requests includes not only the past experience in developing polyimide-based composite copper foil but also the ability to respond to changes in secondary battery technology in terms of performance, productivity, and stability of the anode current collector technology. The technology for manufacturing composite copper foil for secondary batteries is not yet fully developed, and there remains the challenge of enhancing the technology's completeness according to customer requirements.

The battery manufacturing process is highly delicate and demanding, requiring thorough consultation and complex testing and approval processes between customers and suppliers before various materials and substrates can be integrated. In particular, for composite copper foil to replace traditional copper foil, the addition of PET or PP results in thinner copper foil, necessitating ultra-thin foil technology with high electrical conductivity as well as strength and elongation properties.

In addition to producing battery foil for electric vehicles, LOTTE Energy Materials leads the market by manufacturing key materials such as printed circuit boards (PCBs) and flexible copper-clad laminates (FCCLs) used in a wide range of electronic products, including TVs, computers, and smartphones. Leveraging its experience in developing PET materials for semiconductor packages that can withstand high temperatures of around 140°C, the company plans to overcome the technical challenges and hurdles of composite copper foil for batteries through collaboration with customers.

Kim Yeon-seop, CEO of LOTTE Energy Materials, stated, 'The copper foil industry is a market that requires a combination of experience, technology, capital, and strong customer relationships, making it difficult for latecomers to enter. As the first company to successfully localize copper foil production in Korea, we aim to secure leadership in the next-generation copper foil market with our accumulated technological expertise and capture future growth opportunities.'