biostudies-literatureAllen JPNatural Sciences and Engineering Research Council of CanadaEuropean Research CouncilFaraday InstitutionRoyal SocietyRWTH Aachen University10147-10163https://www.ebi.ac.uk/biostudies/studies/S-EPMC12569987biostudies-literatureUnknown18(23)The dissolution of transition metals from lithium-ion battery materials contributes to cell failure. Developing a better understanding of transition metal solvation, reactivity, and deposition will help mitigate transition metal dissolution and, thus, facilitate batteries with higher capacity and longer lifetime. In this work, Mn²⁺ and Ni²⁺ coordination in degraded LiPF₆ carbonate electrolyte solutions is examined <i>via</i> ¹H and ¹⁹F NMR relaxometry at ambient temperatures and pulsed (double resonance HYSCORE and ENDOR) EPR spectroscopy of the frozen solutions. Critically, the solvation spheres of transition metals in heat-degraded electrolytes are shown to differ from those found in pristine electrolytes, with significant coordinatiEnergy & environmental scienceTransition metal coordination to degradation products in battery electrolytes revealed by NMR and EPR spectroscopy.PMC12569987FIRG001835073rwth0701Jonsson EEichel RAGranwehr JAllen JPGrey CPSzczuka CfalseTransition metal coordination to degradation products in battery electrolytes revealed by NMR and EPR spectroscopy.The dissolution of transition metals from lithium-ion battery materials contributes to cell failure. Developing a better understanding of transition metal solvation, reactivity, and deposition will help mitigate transition metal dissolution and, thus, facilitate batteries with higher capacity and longer lifetime. In this work, Mn²⁺ and Ni²⁺ coordination in degraded LiPF₆ carbonate electrolyte solutions is examined <i>via</i> ¹H and ¹⁹F NMR relaxometry at ambient temperatures and pulsed (double resonance HYSCORE and ENDOR) EPR spectroscopy of the frozen solutions. Critically, the solvation spheres of transition metals in heat-degraded electrolytes are shown to differ from those found in pristine electrolytes, with significant coordinati2025-01-01T00:00:00Z2025 Nov2026-06-06T13:21:13.41Z2026-05-31T03:07:22.334ZS-EPMC125699874117051010.1039/d5ee01250c