Fatigue processes in commercial LiCoO2 batteries: In situ neutron diffraction and electrochemical study

In situ high-resolution neutron powder diffraction along with electrochemical analysis was used to study fatigue processes in commercial LiCoO2 (18650-type) batteries. The electrochemical and structural behavior of cathode and anode materials in fully charged and discharged states has been studied for cells exhibiting different cycling at 25°C and 50°C. High-resolution neutron powder diffraction leads us to observe simultaneous changes in LiCoO2 cathode and graphitic anode, which are related to lithium de-/intercalation processes during the battery operation. Detailed features of the battery organization and details of its evolution on a micrometer scale have been visualized using neutron radiography and tomography.