• Nanoscale electrochemical charge transfer kinetics investigated by electrochemical scanning microwave microscopy

    Mohamed Awadein, Maxwell Sparey, Simon Grall, Ferry Kienberger, Nicolas Clement, Georg Gramse
    We show how microwave microscopy can be used to probe local charge transfer reactions with unprecedented sensitivity, visualizing surface reactions with only a few hundred molecules involved. While microwaves are too fast under classical conditions to interact and sense electrochemical processes, this is different at the nanoscale, where our heterodyne microwave sensing method allows for highly sensitive local cyclic voltammetry (LCV) and local electrochemical impedance spectroscopy (LEIS).
  • Quantitative Cell Classification Based on Calibrated Impedance Spectroscopy and Metrological Uncertainty

    Amin Moradpour, Manuel Kaspar, Ferry Kienberger
    Electrochemical impedance spectroscopy (EIS) is widely used for battery cell testing in industrial production and R&D labs. This work addresses the use of EIS calibration and uncertainty analysis in cell classification. Five scenarios are investigated to discuss qualitatively the impact of calibration and uncertainty on classification.
  • Operando Scanning Electrochemical Probe Microscopy during Electrocatalysis

    Carla Santana Santos, Bright Nsolebna Jaato, Ignacio Sanjuán, Wolfgang Schuhmann, and Corina Andronescu
    This review focused in the recent progress in operando scanning electrochemical probe microscopy (SEPM) measurements during electrocatalysis. SEPM techniques can disclose the local electrochemical reactivity of interfaces in single-entity and sub-entity studies. The powerful operando SEPM measurements can correlate electrochemical activity with changes in surface properties as well as provide insight into reaction mechanisms. The capabilities of SEPMs are showcased toward toward the reduction and evolution of O2 and H2 and electrochemical conversion of CO2. Emphasis is given to scanning electrochemical microscopy (SECM), scanning ion conductance microscopy (SICM), electrochemical scanning tunneling microscopy (EC-STM), and scanning electrochemical cell microscopy (SECCM).
  • Elucidating Degradation Mechanisms of Silicon-graphite Electrodes in Lithium-ion Batteries by Local Electrochemistry

    Nomnotho Jiyane, Dr. Enrique García-Quismondo, Prof. Dr. Edgar Ventosa, Prof. Dr. Wolfgang Schuhmann, Dr. Carla Santana Santos
    The integrity of the solid electrolyte interphase (SEI) formed on the negative electrode of lithium-ion batteries (LIB) is especially critical for the performance of next-generation LIBs comprising silicon-carbon based electrode materials. Scanning electrochemical microscopy (SECM) is proposed as local electrochemical technique to investigate the degradation mechanisms of advanced negative electrodes.


  • 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.
  • New Technique for Probing the Protecting Character of the Solid Electrolyte Interphase as a Critical but Elusive Property for Pursuing Long Cycle Life Lithium-Ion Batteries

    Enrique Garcia-Quismondo, Sandra Alvarez-Conde, Guzmán Garcia, Jesús I. Medina-Santos, Jesús Palma, and Edgar Ventosa
    In this work, a new, cheap and easily-implementable methodology to analyzes the quality of the Solid Electrolyte Interphase (SEI) on the negative electrode of Li-ion batteries (LIBs) is proposed. First, a redox-mediator is added in the electrolyte after the SEI formation cycle, and the redox mediator leads to an internal self-discharge process that is inversely proportional to the electrically-insulating character of the SEI. Second, a few charge and discharge cycles are applied to the battery and the presence of the redox-mediator provokes a shuttle effect enables by the lack of electrically protecting character of the SEI which consumes charges decreasing the coulombic efficiencies, enhancing the sensibility to the SEI protecting nature. We believe that the findings based on the application of this mediator-enhanced coulometry can be used to accurately predict the cyclic behavior of LIBs under extended operating conditions, which is especially relevant for a better comprehension of future industrial needs for battery R&D in cell components and production fields.
  • Measurement Uncertainty in Battery Electrochemical Impedance Spectroscopy

    Amin Moradpour, Manuel Kaspar, Johannes Hoffmann, Ferry Kienberger
    Accurate measurement of the impedance over a broad frequency spectrum is of high relevance in battery tests, also requiring specific calibration methods and evaluation of error bounds. Here, we report for the first time a comprehensive uncertainty analysis of calibrated EIS for batteries. We aim to identify two uncertainty sources, the fixture repeatability and measurement noise, and evaluate their effect on the measured impedances.
  • Fast Li-ion Storage and Dynamics in TiO2 Nanoparticle Clusters Probed by Smart Scanning Electrochemical Cell Microscopy

    Emmanuel Batsa Tetteh, Dimitrios Valavanis, Enrico, Daviddi, Siangdong Xu, Carla Santana Santos, Edgar Ventosa, Daniel Martin-Yerga, Wolfgang Schuhmann, Patrick R. Unwin
    Anatase TiO2 is a promising material for Li-ion (Li+) batteries with fast charging capability. However, Li+ (de)intercalation dynamics in TiO2 remain elusive and reported diffusivities span many orders of magnitude. Here, we develop a smart protocol for scanning electrochemical cell microscopy (SECCM) with in situ optical microscopy (OM) to enable the high-throughput charge/discharge analysis of single TiO2 nanoparticle clusters.
  • Calibrated Electrochemical Impedance Spectroscopy and Time-Domain Measurements of a 7 kWh Automotive Lithium-Ion Battery Module with 396 Cylindrical Cells

    Manuel Kaspar, Manuel Moertelmaier, Mykolas Ragulskis, Nawfal Al-Zubaidi R-Smith, Johannes Angerer, Mathias Aufreiter, Alberto Romero, Jakob Krummacher, Jianjun Xu, David E. Root, Ferry Kienberger
    A 7 kWh automotive battery module with 396 interconnected cells was tested with electrochemical impedance spectroscopy (EIS) and time-domain pulsing over 260 charge-discharge cycles. An EIS calibration workflow was developed for low complex impedance values in a frequency range of 1 kHz to 50 mHz. Significant corrections on the resistance and the reactance were obtained from the calibration, particularly at frequencies above 100 Hz.