Nippon Mining & Metals Expands Rolled Cu-Sn Foil Sales for Li Battery

Nippon Mining & Metals aims to expand sales of its original rolled copper foil, “HS1200,” as a material of negative electrode for automotive lithium ion batteries. The firm plans to start commercial production of HS1200 within 3 years and increase rolled copper foil production for automotive lithium ion batteries to several ten tonnes per month.

HS1200 is a rolled copper foil containing tin at 0.12%. The firm can provide the product as thin as 6-7 micrometers of thickness and above 10,000 meters of length. HS1200 represents higher strength than electrolytic copper foil and higher heat resistance than conventional rolled copper foil. Battery makers can improve the yield rate. The demand for lithium ion battery is expected to grow from electric vehicles and hybrid cars.

Rolled copper foil has high strength and flat surface while the tension strength rapidly lowers under the temperature as high as 100 degrees Celsius, for example, in an annealing process. HS1200 maintains tension strength at 250 degrees Celsius. Battery makers can decrease scratches and wrinkles on the surface.

At the same time, HS1200 shows 90% electric conductivity even containing tin, as high as conventional rolled copper foil.