BMW_Factors influencing the thermal stability of li-ion batteries.pdf
• Onset of exothermic reactions is determined by the anode side Deposition of metallic lithium on the anode surface should be prevented Effective and thermally stable SEI is key for a safe LIB • High reactivity of the cathode in presence of electrolyte dominates the kinetics during thermal runaway Layered and spinel-type electrodes exhibit a decreased thermal stability in the charged state The presence of nickel largely reduces the thermal stability of positive active materials (especially in the charged state; Ni4+) independent of the structure (layered/spinel) An increasing nickel content in the NCM structure intrinsically reduces the thermal stability Overall, aging effects have a larger influence on the thermal stability of layered transition metal oxides like NCM compared to spinel-type or olivine-type active materials