TY - CONF AU - Barysch, Vera AU - Wolff, Beatrice AU - Schleker, Peter Philipp Maria AU - Jakes, Peter AU - Streun, Matthias AU - Granwehr, Josef AU - Eichel, Rüdiger-A. TI - DNP at 0.34 T for the Investigation of Batteries M1 - FZJ-2025-03809 PY - 2025 AB - The performance and lifespan of rechargeable lithium batteries are largely determined by intricate interfacial phenomena occurring at the electrode-electrolyte interface. A key element in this process is the solid electrolyte interphase (SEI), a passivating layer that develops on the electrode surface during battery cycling. Despite its importance, the SEI structure and composition remain difficult to characterize.[1] To achieve higher energy densities, battery designs are increasingly exploring anode-free configurations, where lithium is deposited directly onto a current collector like copper, rather than relying on a conventional lithium-based anode. While this approach holds significant promise, it also presents new challenges — most notably, the formation of lithium dendrites. These needle-like structures can pierce the separator, potentially leading to short circuits or battery failure.[2] Despite extensive research on lithium plating and dendrite formation, the molecular formation processes are not yet fully understood.Dynamic nuclear polarization (DNP) provides a powerful means to gain deeper insight into this phenomenon. By transferring polarization from electron spins to nuclear spins, DNP significantly enhances the sensitivity of NMR, particularly under low magnetic field conditions. We present combined EPR and DNP-enhanced 7Li NMR measurements of lithium on copper, performed using a custom-built setup operating at 0.34 T.[3] The resulting enhanced 7Li NMR signal allows for the observation of electrochemically deposited lithium on copper, harvested from a Cu vs. Li cell, with an enhancement larger than 400. Additionally, upon saturation of the lithium electron resonance, the 1H signal from the nearby electrolyte exhibited approximately a twofold enhancement, suggesting the capability to probe the SEI. These measurements utilized a battery cell housing specifically designed for EPR,[4] highlighting its suitability for future in operando studies.Literature:[1] M. A. Hope et al., Nat. Commun. 2020, 11, 2224.[2] K.N. Wood et al., ACS Energy Lett. 2, 2017, 3, 664.[3] Barysch et al., Sci. Rep. 2025, 15, 18436.[4] A. Niemöller et al., J. Chem. Phys. 2018, 148, 014705. T2 - 46. Jahrestagung der Fachgruppe Magnetische Resonanz (FGMR) 2025 CY - 15 Sep 2025 - 18 Sep 2025, Bonn (Germany) Y2 - 15 Sep 2025 - 18 Sep 2025 M2 - Bonn, Germany LB - PUB:(DE-HGF)24 UR - https://juser.fz-juelich.de/record/1046456 ER -