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News Release

Notice on Decision to Uphold Basic Patent on Electrodeposited Copper Foil for Lithium Ion Batteries

February 28, 2012

In an invalidation trial with respect to the Basic Patent on Electrodeposited Copper Foil for Lithium Ion Batteries held by Furukawa Electric Co., Ltd. (Furukawa Electric, hereafter), the Japan Patent Office has delivered a decision upholding Furukawa Electric's patent.

Background and Details

Lithium ion secondary batteries are widely used in consumer fields such as mobile phones and notebook PCs, and with the widespread adoption of electric vehicles, demand is forecast to grow even further in the future. Furukawa Electric developed an electrodeposited copper foil capable of improving battery performance for the anode material of lithium ion batteries, and was awarded a patent for the technology in 2005. Furukawa Electric's NC-WS electrodeposited copper foil for lithium ion batteries enjoys a world-leading share of roughly 40% of the global market.

The lithium ion secondary batteries currently manufactured and sold in Japan mainly use electrodeposited copper foil, and use of this basic patent is considered mandatory.

While the validity of those rights were challenged in 2010 when the Japan Patent Office was asked to conduct an invalidation trial for the patent, this past February 17, the Office delivered the decision that the patent should be upheld (decision of validity).

For its part, Furukawa Electric will continue to expand sales to better meet the demands of customers, and at the same time seek to create and utilize useful intellectual property rights.

Details of the Patent

Patent No.: 3742144
Name: Non-aqueous Electrolyte Secondary Battery and Flat Current Collector for Non-aqueous Electrolyte Secondary Batteries
Details: Discovered non-aqueous electrolyte secondary batteries containing lithium ion secondary batteries, and effective surface roughness and surface treatment conditions for electrodeposited copper foil for the flat current collectors used therein.

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