KEYNOTE LECTURE

Alessandro Cultrera

INRIM – Istituto Nazionale di Ricerca Metrologica, Torino, Italy

The electrical impedance of a device is related to both its macroscopic structure and to the electromagnetic properties of its constituent materials. Impedance-based techniques are powerful material characterisation tools: they can quantify, through proper modeling, the material bulk and interface polarization and transport mechanisms of the device materials at the macro-, meso- and microscopic scale. These methods span from standard LCR measurements to advanced techniques such as electrical impedance tomography (EIT) for mapping material conductivity and electrochemical impedance spectroscopy (EIS), which is widely used to assess materials, devices and modules. Reliable impedance measurements are essential for defensible decision-making from the material to the device level, supporting materials characterisation, chemistry selection, device state-of-health assessment, and the quantified evaluation of impedance-estimation accuracy. This talk presents and discusses key aspects of impedance metrology, including measurand definition and traceability, quantities of influence, and measurement uncertainty. These concepts will be addressed in the context of impedance measurements applied to energy-storage-oriented materials and devices, highlighting their role in ensuring reliable measurement results that are fundamental for a sound interpretation of material properties and device performance, including the reliability of prospective onboard implementations in electric vehicles.

Alessandro Cultrera received the degree in Physics and the Ph.D. degree in Chemical and Materials Science from the Università degli Studi di Torino, Turin, Italy. In 2014, he joined the Istituto Nazionale di Ricerca Metrologica (INRIM), Turin, as a postdoctoral fellow with the Quantum Metrology and Nano Technologies Department, where he worked on electrical characterization of nanostructured materials, precision electronic measurements, and calibration methods. Since 2022, he has been a Researcher with INRIM in electrical metrology. His research activity is focused on electrical impedance metrology applied to both calibration methods and precision measurements of materials electrical properties. A few topics covered are impedance tomography for quantitative conductivity mapping of thin-film, two-dimensional, and nanostructured materials, including graphene, novel calibration methods for signal recovery instrumentation like lock-in amplifiers, electrical noise spectroscopy, supercapacitor characterization, and traceability of electric power measurements under non-sinusoidal distorted regimes. Since 2019 he is a member of Comitato Elettrotecnico Italiano and participates in IEC/TC 113 standardization activities on nano-enabled electrotechnical systems characterization.