Improving microstructure of silicon/carbon nanofiber composites as a Li battery anode

Journal Article · Tue Jan 01 00:00:00 EST 2013 · Journal of Power Sources

DOI:https://doi.org/10.1016/j.jpowsour.2012.08.026· OSTI ID:1091683

Howe, Jane Y ^[1]; Meyer, III, Harry M ^[1]; Burton, David J. ^[2]; Qi, Dr. Yue ^[3]; Nazri, Maryam ^[2]; Nazri, G. Abbas ^[4]; Palmer, Andrew C. ^[2]; Lake, Patrick D. ^[2]

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1. ORNL
2. Applied Sciences, Inc.
3. General Motors Corporation
4. General Motors Corporation-R&D

We report the interfacial study of a silicon/carbon nanofiber (Si/CNF) nanocomposite material as a potentially high performance anode for rechargeable lithium ion batteries. The carbon nanofiber is hollow, with a graphitic interior and turbostratic exterior. Amorphous silicon layers were uniformly coated via chemical vapor deposition on both the exterior and interior surfaces of the CNF. The resulting Si/CNF composites were tested as anodes for Li ion batteries and exhibited capacities near 800 mAh g1 for 100 cycles. After cycling, we found that more Si had fallen off from the outer wall than from the innerwall of CNF. Theoretical calculations confirmed that this is due to a higher interfacial strength at the Si/Cedge interface at the inner wall than that of the Si/C-basal interface at the outer wall. Based upon the experimental analysis and theoretical calculation, we have proposed several interfacial engineering approaches to improve the performance of the electrodes by optimizing the microstructure of this nanocomposite.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1091683
• Journal Information: Journal of Power Sources, Vol. 221, Issue 1; ISSN 0378-7753
• Country of Publication: United States
• Language: English