High-Potential Test for Quality Control of Separator Defects in Battery Cell Production

Lithium-ion batteries are a key technology for electromobility; thus, quality control in cell production is central aspect the success of electric vehicles. The detection defects and poor insulation behavior separator essential high-quality batteries. Optical methods unable to detect small but still relevant layer, e.g., pinholes or particle contaminations. This gap can be closed by executing high-potential testing analyze performance electrically insulating layer pouch cell. Here, we present an experimental study identify different on dry stacks basis voltage stress mechanical pressure. In addition, finite element modeling (FEM) used generate physical insights into partial discharge examining defect structures corresponding fields, including topographical electrode roughness, impurity particles, voids separator. test results show that hard discharges associated with significant defects. Based study, 350 450 V pressure 0.3 0.6 N/mm2 identified as optimum ranges methodology, resulting failure rates up 85%.