Lithium distribution and transfer in high-power 18650-type Li-ion cells at multiple length scales
Dominik Petz, Martin J. Mühlbauer, Volodymyr Baran, Alexander Schökel, Vladislav Kochetov, M. Hofmann, Vadim Dyadkin, Peter Staron, G. Vaughan, Ulrich Lienert, Peter Müller‐Buschbaum, Anatoliy Senyshyn
Abstract
The distribution of lithium inside electrodes of a commercial Li-ion battery of 18650-type with LiFePO4 cathode and graphite anode is investigated on different length scales using neutron diffraction, X-ray (synchrotron-based) diffraction and X-ray computed tomography. Evolution of 2D (in-plane) lithium distribution in lithiated graphite is monitored during charge/discharge using millimeter-sized spatial resolution. Micrometer-sized details of cell organization and lithiation of both the positive and negative electrodes are obtained from diffraction-based tomography applying synchrotron radiation. In-situ lithiation of the cathode over its thickness and development of the lithium concentration front during cell charge/discharge is traced by diffraction-based profiling with a micrometer-sized synchrotron beam in a single-layer electrochemical cell.