Operando neutron imaging study of a commercial Li-ion battery at variable charge-discharge current densities

We report an operando neutron imaging study of a commercial ICR 10440 Li ion battery during charge and discharge. The cylindrical battery with a spiral configuration is composed of a multiphase layered oxide cathode and graphite anode. In spite of a two-dimensional nature of the projection data of this time-resolved study, structural and functional details of the neutron radiography study were successfully uncovered and visualized. The spatially resolved measurements with a resolution of 40 µm enabled to observe Li redistribution between the electrodes as well as a circulation of the electrolyte between the central column and the electrode layers at different states of charge (SoC) and at different current rates. Furthermore, ex-situ tomographic studies of the battery revealed the fine details of the structural inhomogeneity within the cell.