Although current collectors take up more weight than active materials in most lithium ion battery cells, so far research has been focused mainly on improving gravimetric capacities of active materials. To address this issue of improving gravimetric capacities based on overall cell components, we develop freestanding nanocomposites made of carbon nanofibers (CNFs) and silicon nanowires (SiNWs) as metal current collector-free anode platforms. Intrinsically large capacities of SiNWs as active materials in conjunction with the light nature of freestanding CNF films allow the nanocomposites to achieve 3-5 times improved gravimetric capacities compared to what have been reported in the literature. Moreover, three-dimensional porous structures in the CNF films facilitate increased mass loadings of SiNWs when compared to flat substrates and result in good cycle lives over 40 cycles. This type of nanocomposite cell suggests that 3D porous platforms consisting of light nanomaterials can provide for higher gravimetric and areal capacities when compared to conventional battery cells based on flat, heavy metal substrates. © 2010 Elsevier B.V. All rights reserved.
|Original language||English (US)|
|Number of pages||6|
|Journal||Journal of Power Sources|
|State||Published - Dec 15 2010|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): KUS-11-001-12
Acknowledgements: This work was supported from the King Abdullah University of Science and Technology (KAUST) Investigator Award (No. KUS-11-001-12). J. M. acknowledges funding support from the National Science Foundation Graduate Research Fellowship and the National Defense Science and Engineering Graduate Fellowship.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.