• Building a full copper foil lineup for rechargeable batteries with
  tensile strength more than twice that of existing foils

• Responding to future market needs of rechargeable batteries with
  ultra-thin foil manufacturing technology together with high-strength, high-heat
  resistant foil manufacturing technology

   

SK nexilis (CEO & President
Woncheol Park), the cooper foil business unit for rechargeable batteries of SKC,
developed the technology to produce ultra-strength (U) cooper foil and
successfully rolled out a full lineup of high-strength cooper foils. The
high-strength cooper foil is developed to meet future market needs of durable rechargeable
batteries such as faster processing speed and greater product capacity, enhancing
the price competitiveness of rechargeable batteries and expanding battery
capacity.

The company successfully developed the
technology for mass production of U cooper foil with a tensile strength of
65kgf/㎟ for the first time in the
industry. This means that the new cooper foil can withstand more than two times
the pulling force of existing standard products. The mass production technology
allows the company to build a full lineup of four types of U cooper foil with a
tensile strength of 40~65kgf/㎟.

SK nexilis has the cooper foil lineup to
satisfy the needs of customers, a so-called BEST which is an acronym of battery
(B), elongation (E), strength (S), and thin (T). It represents the standard
battery foil (B) commonly used in diverse applications, battery foil with enhanced
elongation rate (E), battery foil with reinforced tensile strength (S), and
battery foil less than 5 ㎛ (T) thick. The newly
added product is the ultra-strength (U) battery foil with higher tensile
strength compared to the S battery foil.

The high-strength cooper foil has high
heat resistance, which can withstand high temperatures without physical changes.
SK nexilis can also make 4㎛-thick (1/30 of human
hair), 1.3 m-wide, and 30 km-long cooper foil per roll

An anode material for rechargeable batteries goes through the
process of coating the cooper foil with anode substances like graphite and
silicone. Fast coating speed and rapid drying at high temperatures offer price
competitiveness, yet increases the risk of defects as the cooper foil is torn
or creased. The high-strength cooper foil has high tensile strength and high heat
resistance, reducing the risk of defects and improving productivity.

The high-strength cooper foil is a good solution for the
battery capacity expansion trends. The application of thin cooper foil increases
the coating area of anode substances to expand battery capacity, but can cause a
risk of failure in the process. However, risk will be reduced if high-strength
cooper foil is used.

To improve the physical properties of
cooper foil, SK nexilis has focused for a decade on developing the additive
technology which is the key to control the physical properties of copper foils.
The effort to enhance additive technology in realizing and retaining the
desired properties led to the successful development of cooper foil with
revolutionary tensile strength and high heat resistance. The addition of handling
technology in making thin, wide, and long cooper foil for stable mass
production also allows for the production of high-strength thin foils in
various thicknesses.

 “With
the expansion of EV battery capacity and the improvement of productivity
becoming important, the high-strength cooper foil market is expected to grow
rapidly more than 10 times over the years,” said an SK nexilis official. “We
will contribute to the advancement of the EV and rechargeable battery industry through
continuous R&D efforts to develop high-end, high-quality foils,” added.
[The End]

[Cooper foil production; SK nexilis secures
the technology to produce U battery foil with a tensile strength more than
twice that of existing products to build a full lineup of high-strength cooper
foils.]