In:
ECS Transactions, The Electrochemical Society, Vol. 41, No. 32 ( 2012-05-04), p. 27-35
Abstract:
Pure Si thin flakes (Si Leaf Powder® (Si-LP)) of different thicknesses (50, 100, 200, 300 and 400 nm) were prepared, and their charge/discharge properties were investigated as anode materials for lithium ion batteries (LIBs). Thickness of the thin Si-LP (100 nm) changed reversibly during charging and discharging, while the expanded thickness upon charging was kept after fully discharged for the thick one (300 nm), indicating insufficient Li de-alloying at C/6 rate. The slower kinetics for the thicker Si-LPs was also confirmed by examination of the open circuit potential (OCP) and the rate capability. These suggested that Li atoms diffused easily within the thinner Si-LPs and the uniform Li distribution suppressed the physical stress due to the Li alloying and de-alloying, resulting a good cycleability. In addition, addition of vinylene carbonate (VC) in electrolyte reduced charge transfer resistance of the Li alloying/de-alloying reaction and much more improved the cycleability of Si-LPs.
Type of Medium:
Online Resource
ISSN:
1938-5862
,
1938-6737
Language:
Unknown
Publisher:
The Electrochemical Society
Publication Date:
2012
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