Experimental and computational structure study of the commercial NMC622 lithium-ion battery electrode.

Reliable and traceable characterization of battery electrode materials is essential for standards and harmonized measurements in the growing lithium-ion battery sector. We report a coordinated interfacility study of commercial cathode NMC622, performed within the EURAMET projects OpMetBat and HyMetBat to evaluate reproducibility, uncertainty, and cross-method comparability. A single batch was analyzed using synchrotron X-ray diffraction, high-resolution neutron diffraction at two facilities, transition metal K-edge XANES/EXAFS, DFT-based electronic structure and spectral simulations, and electrochemical measurements. Neutron diffraction yields consistent lattice parameters and transition metal occupancies and enables traceable quantification of lithium content. Lithium loss from neutron refinement agrees with electrochemical charge extraction at low delithiation, whereas deviations at higher states of charge indicate parasitic faradaic processes. XANES and EXAFS confirm local coordination and oxidation states, while DFT reproduces spectral features. Operando impedance correlates with structural evolution and supports state-of-charge metrology. Together, these cross-facility results establish a robust metrological workflow for layered oxide cathode materials. Graphical abstract: Supplementary Information: The online version contains supplementary material available at https://doi.org/10.1557/s43578-026-01938-y.