(Invited) Nanocrevasse-Rich Carbon Fibers for Scalable Production and Stable Performance of Lithium and Sodium Metal Anodes

Abstract

The metallic lithium (Li) and sodium (Na) anodes have long been considered as ideal anodes for high energy density batteries due to its high theoretical capacity and lowest reduction potential. However, the challenges induced by dendritic growth on metallic Li and Na anodes hinder the practical applications. Finding a stable host structure with polar functional groups is an essential strategy to prevent the Li and Na dendrite growth with improved electrochemical performance. Recently, many researchers have concentrated on development of host structure for storing the Li/Na metal. Nevertheless, complexity and inconvenience of the synthetic process still require further improvement of Li/Na metal anodes. In this talk, we will introduce a facile synthetic method to fabricate alkali metal/carbon composites which contain nanocrevasses in carbon fibers to facilitate the penetration of molten alkali metal via capillary forces. When the molten alkali metal is contacted to the carbon fibers with rGO-like crevasses, the metallic liquid infiltrates into the fine gaps within a few seconds. As well, the nanocrevasses provide a pretty large surface area which is enough to lower the specific current, ultimately leading to suppression of dendritic formation. The resulting alkali metal/carbon composites exhibit stable long-term cycling over hundreds of cycles. In addition, Unlike previous studies that focused on improving the performance of metal batteries, we carried out the test after applying the composite to actual equipment with scalable production process using recycled metal waste. Thus, the addition of nanocrevasses to carbon fiber as a scaffold for alkali metals can generate environmentally friendly and cost-effective composites for practical electrode applications References Go, W.; Kim, M.-H.; Park, J.; Lim, C.H.; Joo, S.H.; Kim, Y.; Lee, H.-W. Nano Lett. 2019, 19, 1504-1511.Lin, D.; Liu, Y.; Liang, Z.; Lee, H.-W.; Sun, J.; Wang, H.; Yan, K.; Xie, J.; Cui, Y. Nat. Nanotechnol. 2016, 11, 626-632.Zhang, R.; Chen, X.; Chen, X.; Cheng, X.; Zhang, X.; Yan, C.; Zhang, Q. Chem. int. Ed. 2017, 56, 7764-7768.Yun, J.H.; Kim, J.H.; Kim, D.K.; Lee, H.-W. Nano Lett. 2018, 18, 475–481. Figure 1