Yasui Seiki Co., (USA)

Patch Coating System

Lithium chemistry 'secondary' (rechargeable) batteries are an important technology for electronic, portable power, and backup applications.

Basic Technology:

Electrode slurries, both 'anode' and 'cathode' types, are coated directly onto metal foils, 'primed' foils, or onto release films, for later lamination to foils or expanded foils. Profile of the electrodes (and the active materials in the electrodes) is very important for safe, efficient rechargeable batteries.

"Patch Coating" is the stop/start coating of rectangles of coating material onto foils directly. Patch sizes are set to accommodate a specific battery design. Length of the coated and un-coated portions of the coating, as well as the profile of the "head" and "tail" of the patches is adjustable with Yasui Seiki battery coaters.

Patch coating is used to conserve electrode materials, and to leave an un-coated border around the electrode. Reverse side patch registration is a must for 2-sided electrodes.

Uses:

Lithium Secondary batteries of "Lithium Ion", and "Lithium Polymer" chemistries are used for electronic, medical, and portable power (cordless) applications. Lithium chemistry rechargeable batteries provide high energy storage. The performance characteristics and cycle life of these batteries is friendly to modern electronic devices.

Yasui Seiki Contributions:

Yasui Seiki provides battery coating machines with optional patch coating capability. Registration errors of patches, and backside patches is less than 1 mm, and any errors with the Yasui Seiki system are non-cumulative.

We state electrode thickness profiles are to be +/- 2.5 pct, however, recent advances have yielded repeatable performance of +/- 1.5 pct for specific applications, either with or without patch coating.

Our work continues to improve our drying technology to push higher coating speeds for thick battery electrodes.

Yasui Seiki has enhanced battery electrode profile uniformity and repeatability through improvements in Slot Dies, Slot Die mounting precision, carrier web speed uniformity, and web tension uniformity. Contact us, we'll be happy to prove our capabilities to you.