Pub. No.: WO/2014/093519
International Application No.: PCT/US2013/074449
Applicants: APPLIED MATERIALS, INC. [US/US]; 3050 Bowers Avenue Santa Clara, CA 95054 (US)
Inventors: HERLE, Subramanya, P.; (US). GORDON, Joseph, G.; (US)
Agent: DANIELSON, Mark, J.; Pillsbury Winthrop Shaw Pittman LLP P.O. Box 10500-intellectual Property Group McLean, VA 22102 (US)
Abstract: The present invention relates generally to electrochemical energy storage devices such as Li-ion batteries, and more particularly to a method of providing uniform ceramic coatings with controlled thicknesses for separators in such storage devices. Some embodiments of the invention utilize a layer by layer coating of nano/micro-sized particles dispersed in a solvent, which can be aqueous or non-aqueous. Other embodiments of the invention utilize a dry process such as PVD for depositing a ceramic film on a porous polyolefin separator. According to certain aspects of the invention, advantages of this approach include the ability to achieve a denser more uniform film with better controlled thickness with less waste and higher yield than current ceramic coating technology. An advantage of a ceramic coated separator is increased safety of cells.