• Correlative Electrochemical Microscopy for the Elucidation of the Local Ionic and Electronic Properties of the Solid Electrolyte Interphase in Li-ion Batteries

    Carla S. Santos, Alexander Botz, Aliaksandr S. Bandarenka, Edgar Ventosa, Wolfgang Schuhmann
    The solid-electrolyte interphase (SEI) plays a key role in the stability of lithium-ion batteries as the SEI prevents the continuous degradation of the electrolyte at the anode. We combine the feedback and multi-frequency alternating-current modes of scanning electrochemical microscopy (SECM) for the first time to assess quantitatively the local electronic and ionic properties of the SEI varying the SEI formation conditions and the used electrolytes in the field of Li-ion batteries (LIB).
  • Process-Product Interdependencies in Lamination of Electrodes and Separators for Lithium-Ion Batteries

    Ruben Leithoff, Arian Fröhlich, Steffen Masuch, Gabriela Ventura Silva, Klaus Dröder
    In today’s cell production, the focus lies on maximizing productivity while maintaining product quality. To achieve this, the lamination of electrode and separator is one key process technology, as it bonds the electrode and separator to form mechanically resilient intermediate products.This paper addresses the investigation of interdependencies and proposes three characterization methods (grey scale analysis, high potential tests, electrochemical cycling and C-rate tests).
  • Advanced Electrochemical Impedance Spectroscopy of Industrial Ni-Cd Batteries

    Nawfal Al-Zubaidi R-Smith, Manuel Kaspar, Peeyush Kumar, Daniel Nilsson, Björn Marlid, Ferry Kienbarger
    Advanced EIS was applied to characterize industrial Ni-Cd batteries and to investigate the electrochemical redox processes. A two-term calibration workflow was used for accurate complex impedance measurements across a broad frequency range of 10 mHz to 2 kHz, resulting in calibrated resistance and reactance values. The EIS calibration significantly improved the measurements, particularly at high frequencies above 200 Hz, with differences of 6–8% to the uncalibrated impedance.
  • Electrochemical impedance spectroscopy error analysis and round robin on dummy cells and lithium-ion-batteries

    Manuel Kaspar, Arnd Leike, Johannes Thielmann, Christian Winkler, Nawfal Al-Zubaidi R-Smith, Ferry Kienberger
    An interlaboratory Round-Robin comparison between three-labs is conducted where calibrated electrochemical-impedance-spectroscopy (EIS) is measured on prismatic cell dummies and prismatic batteries. Advanced EIS calibration workflow is employed allowing for precise measurements of low micro-Ohm impedances in a broad frequency range of 50 mHz to 10 kHz. Significant systematic-error corrections are obtained from the calibration.