Effects of momentum transfer on sizing of current collectors for lithium-ion batteries during laser cutting. (1st February 2018)

• Record Type: Journal Article
• Authors: Lee, Dongkyoung; Mazumder, Jyotirmoy
• Is Part Of: Optics & laser technology. Volume 99(2018)
• Page Start: 315
• Page End: 325
• Publication Date: 2018-02-01
• Subjects: Laser cutting -- Lithium-ion battery -- Current collector -- Copper -- Aluminum -- Numerical simulation; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2017.09.016
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlights: The 3D mathematical model of the laser cutting of current collectors is developed. Penetration time, depth, width, and absorptivity, are analyzed with selected laser parameters. Melt pool flow, melt pool geometry and temperature distribution are investigated. The transition from partial to full penetration modes and crest are observed for copper. Not only the crest, but also two deep penetration holes are observed for aluminum. Abstract: One of the challenges of the lithium-ion battery manufacturing process is the sizing of electrodes with good cut surface quality. Poor cut surface quality results in internal short circuits in the cells and significant heat generation. One of the solutions that may improve the cut quality with a high cutting speed is laser cutting due to its high energy concentration, fast processing time, high precision, small heat affected zone, flexible range of laser power and contact free process. In order to utilize the advantages of laser electrode cutting, understanding the physical phenomena for each material is crucial. Thus, this study focuses on the laser cutting of current collectors, such as pure copper and aluminum. A 3D self-consistent mathematical model for the laser cutting, including fluid flow, heat transfer, recoil pressure, multiple reflections, capillary and thermo-capillary forces, and phase changes, is presented and solved numerically. Simulation results for the laser cutting are analyzed in terms of penetration time, depth, width, and absorptivity, based on these selected laser parameters. In addition, melt pool flow, melt pool geometry and temperature distribution are investigated.