Elucidation of the temperature dependence of transition metal (Ni, Co, Mn) dissolution as a function of Ni- and Mn- content of CAMs for Li-i

Operation stability of cathode active materials (CAMs) for Li-ion batteries at elevated temperatures is a major bottleneck to overcome for their broad market penetration. Ageing mechanisms, such as the dissolution of transition metals (TMs) and their subsequent deposition on the anode have been shown to significantly accelerate with increasing temperature, resulting in cell ageing and eventually failure. Within this proposal, we aim for a comparative evaluation of the impact of temperature, upper cut-off potential and TM composition on the dissolution of TMs from conventional (NCM111) and Ni-rich (NCM811 and NCA) CAMs. The dissolved TMs are quantified under operando conditions by probing XANES at Mn, Co, and Ni-K-edges within the electrolyte, as well as on the counter electrode, using a special cell setup which enables both heating and the spatial resolution of TMs within the cell volume.