Environmentally friendly hybrid, plug-in hybrid and full-electric vehicles (EVs) are gaining importance [1]. However, to gain further acceptance by the consumer, it is essential to extend the autonomy range of EVs to be similar to that of a gasoline-fueled car. There is a need for finding next-generation lithium-ion batteries (LIBs) with larger specific capacity and, therefore, higher energy density.

Undoubtedly, one of the most direct strategies to boost the specific capacity of LIBs is to replace the widely used graphite anode with other materials capable of delivering much larger capacities.[2] Among potential candidates, silicon is one of the most promising anode materials, since it offers a theoretical capacity (~3579 mAh/g) approximately 10 times higher than that of graphite (~370 mAh/g) [3]^, [4]. Besides, silicon is the second most abundant element in the earth’s crust, which positions it as a commercial-friendly substitute of carbon materials for anodes of LIBs[5]. Nevertheless, silicon anodes display pronounced capacity fade upon cycling and, thus, presents a great challenge to battery design ^3,4,5.

Another aspect that so far has not been considered nor explored is the influence that temperature would have over the cyclability of silicon anodes in LIBs. To understand its effect, we performed galvanostatic experiments at different temperatures with silicon-based anodes in half-cells. In addition, the effect of using fluoroethylene carbonate (FEC) as an additive was also investigated. The different capacity fading observed and the possible kinetic mechanisms behind that distinct behavior will be discussed here.

We gratefully acknowledge support from the U. S. Department of Energy (DOE), Vehicle Technologies Office. Argonne National Laboratory is operated for DOE Office of Science by UChicago Argonne, LLC, under contract number DE-AC02-06CH11357. The U.S. government retains for itself, and others acting on its behalf, a paid-up nonexclusive, irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the government.

[1] M. Armand and J-M. Tarascon. Nature 2008, 451, 652-657. Building better batteries.

[2] V. Etacheri, R. Marom, R. Elazari, G. Salitra and D. Aurbach. Energy Environm. Sci. 2011, 4, 3243-3262. Challenges in the development of advanced Li-ion batteries: a review.

[3] X. Su, Q. Wu, J. Li, X. Xiao, A. Lott, W. Lu, B. W. Sheldon and J. Wu. Adv. Energy Mater. 2014, 4, 1300882. Silicon-Based Nanomaterials for Lithium-Ion Batteries: A Review.

[4] H. Wu and Y. Cui. Nanotoday 2012, 7(5), 414-429. Designing nanostructured silicon anodes for high energy lithium ion batteries.

[5] U. Kasavajjula, C. Wang and A. J. Appleby. Journal of Power Sources 2007, 163, 1003. Nano- and bulk-silicon-based insertion anodes for lithium-ion secondary cells.