We have performed a low-frequency electron paramagnetic resonance (EPR) study on two (LiNi_0.8Mn_0.1Co_0.1O₂ (NMC)-Li-metal- and NMC-Si-based) solid-state batteries sealed inside an industrial and standard aluminum laminated pouch cell. We observed an EPR spectrum from Li metal, confirming the good penetration of the microwave field through the pouch. We think our approach provides valuable insight for the battery community, paving the way for the quality control of industrial and commercial batteries.

In our study, we correlate the first- and the second-harmonic detection modes of continuous-wave electron paramagnetic resonance (EPR) to identify traces of non-dendritic Li metal present on the graphite anode after multiple electrochemical cycles. Such metallic complexes are a source of limitations which reduce battery life and lead to serious safety issues. To improve their detection, we propose to simultaneously record the first- and second-harmonic EPR spectra.

Could the gesture of an ancient artist applying a paint layer be reconstructed using EPR analysis? In the case of an inorganic pigment widely used in antiquity, Egyptian blue, where the anisotropy of the Cu²⁺ EPR signal reflects the symmetry of the pigment crystallites, we have shown that the orientation distribution of the grains, as revealed by simulation of EPR spectra, is indeed influenced by the nature of the gesture.

Egyptian mummies were covered with an enigmatic black organic matter. Its chemical composition is classically determined by molecular analysis methods, which are destructive by nature. In a new analytical approach based on 1H and 14N hyperfine spectroscopy, we use V⁺ ions, existing at trace level in this black matter, as internal probes for a non-destructive exploration of the material. The results suggest that a common recipe was used for animal and human mummies of different ages.