07 April 2013

Oak Ridge National Laboratory Uses In Situ X-Ray Diffraction (XRD) in Studying Voltage Fading Pathways in Li-Ion Batteries


The Oak Ridge National Laboratory used in situ x-ray diffraction (XRD) to study mechanisms on voltage fading in lithium batteries. This research was presented at a meeting of the American Chemical Society as part of the 245th National Meeting & Exposition of the American Chemical Society. Abstract on XRD follows:

Investigating the voltage fading mechanism in Li1.2Co0.1Mn0.55Ni0.15O2 lithium-ion battery cathode by in situ x-ray diffraction studies

Debasish Mohanty, Oak Ridge National Laboratory
Phone: 865-576-0813
Email: mohantyd@ornl.gov



In this study, in situ x-ray diffraction (XRD) technique was implemented to investigate the voltage fading pathways in lithium-rich Li1.2Co0.1Mn0.55Ni0.15O2 cathode in a lithium-ion battery. A custom designed coin-cell with Kapton® film window of ~ 13mm in diameter opening was fabricated for in situ XRD experiment. The in situ XRD was collected during electrochemical charge/discharge process performed in 2.4-4.8 V voltage window at 10 mA/g rate in fist cycle and after subsequent cycles (16 and 36). The collected in situ XRD patterns were simulated and lattice parameters were calculated to correlate with the electrochemical profile. The results show increase in c-lattice parameter during initial charging up to 4.4 V and subsequently decreases beyond 4.4 V. The a-lattice parameter remains constant at the first cycle plateau region. After 16(36) cycles, (440) cubic spinel reflections were observed which indicate a layer to spinel-like phase transformation and believed to suppress the voltage profile.

RELATED LINKS

Oak Ridge National Laboratory
American Chemical Society