Regensburg 2022 – wissenschaftliches Programm
KFM 25.20: Poster
Donnerstag, 8. September 2022, 15:00–18:00, P2
Dynamics of lithium-distribution in 18650-type LFP|C lithium-ion batteries during electrochemical cycling — •Dominik Petz1,2, Peter Müller-Buschbaum1,2, and Anatoliy Senyshyn1 — 1Heinz Maier-Leibnitz Zentrum (MLZ), Garching, Germany — 2Lehrstuhl für Funktionelle Materialien, Technische Universität München, Garching, Germany
The electrochemical cycling of lithium-ion batteries is characterized by an active transport of lithium ions and electrons, which are exchanged between the cathode and anode materials. Ionic exchange influences structural and chemical properties of electrode materials, which, in turn, affects electrode dimensions and geometry, current density, temperature, pressure, reaction rate, etc. Such parameters are in general neither uniformly nor statically distributed and therefore serve as stabilizing factor for heterogeneous states in lithium-ion batteries, which are typically reflected in the lithium concentration distribution in the electrodes. In most of the studies reported in literature, the lithium distribution has typically been examined in static equilibrium (e.g. in fully charged state), neglecting the evolution of the distribution under real charging conditions like the influence of C-rates, etc.
In this work the evolution of the lithium-ion distribution in the graphite anode was investigated in-operando by spatially-resolved neutron powder diffraction. Neutron data were supplemented by diffraction studies with high-energy photons. The occurrence of lithium inhomogeneities on different length scales was observed and will be presented in the current contribution.