Some of the material in is restricted to members of the community. By logging in, you may be able to gain additional access to certain collections or items. If you have questions about access or logging in, please use the form on the Contact Page.
Mehdi, B. L., Stevens, A., Qian, J., Park, C., Xu, W., Henderson, W. A., … Browning, N. D. (2016). The Impact of Li Grain Size on Coulombic Efficiency in Li Batteries. Scientific Reports. Retrieved from http://purl.flvc.org/fsu/fd/FSU_pmch_27703188
One of the most promising means to increase the energy density of state-of-the-art lithium Li-ion batteries is to replace the graphite anode with a Li metal anode. While the direct use of Li metal may be highly advantageous, at present its practical application is limited by issues related to dendrite growth and low Coulombic efficiency, CE. Here operando electrochemical scanning transmission electron microscopy (STEM) is used to directly image the deposition/stripping of Li at the anode-electrolyte interface in a Li-based battery. A non-aqueous electrolyte containing small amounts of HO as an additive results in remarkably different deposition/stripping properties as compared to the "dry" electrolyte when operated under identical electrochemical conditions. The electrolyte with the additive deposits more Li during the first cycle, with the grain sizes of the Li deposits being significantly larger and more variable. The stripping of the Li upon discharge is also more complete, i.e., there is a higher cycling CE. This suggests that larger grain sizes are indicative of better performance by leading to more uniform Li deposition and an overall decrease in the formation of Li dendrites and side reactions with electrolyte components, thus potentially paving the way for the direct use of Li metal in battery technologies.
Mehdi, B. L., Stevens, A., Qian, J., Park, C., Xu, W., Henderson, W. A., … Browning, N. D. (2016). The Impact of Li Grain Size on Coulombic Efficiency in Li Batteries. Scientific Reports. Retrieved from http://purl.flvc.org/fsu/fd/FSU_pmch_27703188