PET Tape as Source for Self-discharge of Large Format Lithium-ion Batteries

On June 16^th 2023, the ECS Student Chapter Münster and the international graduate school BACCARA (Battery Chemistry, Characterization, Analysis, Recycling and Application) hosted a talk by the renowned research professor Michael Metzger from Dalhousie University in Halifax, Canada. Holding the Herzberg-Dahn chair, he is one of the three principal investigators in the exclusive research partnership with Tesla, which aims to develop even safer, longer-lasting lithium-ion batteries.

During his talk at MEET Battery Research Center, Prof. Metzger shed light on the curious self-discharge of large format lithium-ion batteries. He took the audience on a journey from discovering the phenomenon to finding the actual culprit of the mechanism: the adhesive PET tape. The PET can depolymerize in the chemical environment inside a lithium-ion battery forming dimethyl terephthalate (DMT). This monomer essentially acts as an unwanted redox shuttle that induces the self-discharge of the battery cell, which can eventually lead to a complete discharge over the course of several weeks. Prof. Metzger concluded the talk by suggesting to replace the PET adhesive tape with chemically stable alternatives like polypropylene (PP) and polyimide (Kapton), which virtually eliminates the reversible self-discharge of the investigated cylindrical and pouch cells.

During his stay in Münster, Prof. Metzger took the opportunity to explore cutting-edge laboratories of MEET Battery Research Center and visited the Fraunhofer Research Institution for Battery Cell Production FFB. Also, he met with students and faculty members to discuss current and upcoming research projects, particularly in the context of the 2024 IBA conference in Halifax.

Next event of the ECS student chapter in July

Already next month, on the 25^th of July 2023, the ECS Student Chapter Münster will welcome Dr Rinaldo Raccichini, one of the senior editors of the renowned journal Nature Communications. In his talk, entitled “Understanding the editorial process at Nature journals”, he will discuss what the key editorial differences between Nature, the Nature Research Journals, and Nature Communications are and how to write a paper that deserves to be published in a Nature journal.

Students interested in joining the ECS Student Chapter Münster and enjoying the many benefits, please contact info.chapter.ecs@uni-muenster.de.