Web Coating with Lithium―Technical Solution for Metal Anode Structures in Li Batteries

摘要

An industrial scale pilot machine for single sided vacuum coating of Lithium onto rolls of materials 340 mm wide was built some years ago and has coated lithium onto many different substrates, from polyolefin films to copper foils. To expand the design possibilities of metallic lithium anodes, another, more complex machine has recently begun producing experimental and pilot materials. This new machine can coat lithium onto polymer and foil webs of 150 mm width. It can perform both single side and double side metallic lithium coatings on selected substrates. It is used to perform feasibility studies and gather design data for production machines for economically viable combinations of materials. Scanning Electron Micrographs of the some of the lithium surfaces produced will be discussed. Successful experiments depositing lithium layers from 2 to 20 microns thick onto various polymeric films have been performed. Thermo-physical con- ditions of gaseous lithium transfer from the vaporization source to the substrate were investigated. Design criteria for the lithium vapor generator with minimum heat transfer are discussed.