Lotte Energy Materials Loses Patent Bid On Copper Foil Technologies

 

(Source: Lotte Energy Materials)

Lotte Energy Materials has failed to secure patents for two of its electrolytic copper foil technologies, with South Korea's Intellectual Property Trial and Appeal Board (IPTAB) rejecting the company's appeals against prior refusals. 

On March 19, 2025, the IPTAB dismissed Lotte's requests to overturn rejection decisions for two separate technologies: "Electrolytic copper foil for current collector of secondary battery" (Application No. 1020210146993) and "Electrolytic copper foil with high elongation and high strength characteristic" (Application No. 1020210147045). 

Lotte filed appeals in mid-to-late April 2024, after the Korean Intellectual Property Office initially refused to register the inventions. While the IPTAB has now ruled against Lotte's arguments, the company still has the option to challenge the decisions by filing cancellation lawsuits with the Patent Court.

The company posted revenue of KRW 902.3 billion ($675 million) in 2024, with an operating loss of KRW 64.4 billion and a net profit of KRW 28.8 billion. While sales increased year-over-year, operating income swung to a loss, and net income turned positive.

Lotte Energy Materials derives 70–80% of its revenue from materials, including its electrolytic copper foil product—a thin copper foil created through the electrochemical decomposition of copper sulfate. The material is used in both battery foil applications for electric vehicles and energy storage systems (ESS), and in circuit foils for AI accelerators, TVs, computers, and smartphones.

Lotte is expanding into next-generation battery materials. The company completed a pilot plant for sulfide-based solid-state electrolytes in September 2024 and another for LFP (lithium iron phosphate) cathode active materials in December 2024.

Figures from the patent application titled "Electrolytic copper foil for current collector of secondary battery" (Application No. 1020210146993), filed by Lotte Energy Materials (Source: KIPRIS)

By PatenTrip