Study of Diffusion Kinetics and Microstructure for FeF3-CF (Carbon-Fiber) 3D Composite Electrodes
Figure 1. (a). Voltage vs. capacity profiles of a Li/FeF3 cell (on carbon fiber) cycled between 1.5 V and 4.5 V (C/50 rate) at 60oC. (b) Capacity plotted as a function of cycle number for the Li/FeF3 cell. Capacity is evaluated based only on FeF3 active material.
Although initial cycle life looks promising, we notice capacity fade after 50 cycles clearly suggesting that further investigation are needed to understand the diffusion kinetics and/or structural stability of various intermediate conversion phases. We will present detailed investigation of various reaction phases and the kinetics of FeF3 and FeF2 electrodes at room temperature, 45 and 60 °C based on potentiostatic intermittent titration (PITT), electrochemical impedance spectroscopy (EIS), electron microscopy (S/TEM) and X-ray diffraction (XRD).
This research is sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U. S. Department of Energy.
- S. K. Martha, J. Nanda, H. Zhou, J. C. Idrobo, N. J. Dudney, S. Pannala, S. Dai, J. Wang, and P. V. Braun, RSC Advances. (Accepted 2013).
- S. K. Martha, N. J. Dudney, J. O. Kiggans and J. Nanda, J. Electrochem. Soc., 159, A1652-A1658 (2012).
P. G. Bruce, B. Scrosati, and J-M. Tarascon, Angew. Chem. Int. Ed., 47, 2930-2946 (2008).