Silicon/carbon composites

Holzapfel M, Buqa H, Scheifele W, Novak P, Petrat FM. A new type of nano-sized silicon/carbon composite electrode for reversible lithium insertion. Chem Commun 2005 12 1566-1568. 

Liu Y, Hanai K, Yang J, Imanishi N, Hirano A, Takeda Y. Silicon/carbon composites as anode materials for Li-ion batteries. Electrochem Solid-State Lett 2004 7 A369-A372. 

Saint J, Morcrette M, Larcher D, Laffont L, Beattie S, Peres JP, Talaga D, Couzi M, Tarascon JM. Towards a fundamental understanding of the improved electrochemical performances of silicon-carbon composites. Adv Funct Mater 2007 9 1765-1774. 

Differential capacity plots and cyclic voltammograms (Figs. 11.7 and 11.8) provide further information for the electrochemical properties of the silicon-carbon composite. Differential capacities dg/dE were recorded for the carbon-coated... 

Silicon/Carbon Composites Prepared through Ball Milling... 

Another high-temperature approach for generating silicon/carbon composites is to deposit silicon particles on carbon or vice versa using CVD. Xie et al. [44] reported the deposition of silicon on mesocarbon microbeads (MCMB) by CVD of silane at 450°C and 500°C, but only a very small amount of silicon actually deposited on the MCMB. The material also demonstrated a very high (55%) irreversible loss. Vacuum deposition of nanometer-sized silicon particles on graphite surfaces has also been reported [45, 46]. The as-prepared anode showed an... 

To further improve the mechanical and electrical stability of silicon-based anodes, a hierarchical bottom-up approach (Fig. 15.12) was successfully utilized to develop a three-dimensional nanostructured silicon/carbon porous composite [89]. The existence of pores in the composite granules provides sufficient space to accommodate silicon expansion during lithium insertion. CVD deposition of silicon clusters (Fig. 15.12b) avoids formation of SiO thus reducing the first cycle, irreversible capacity. A high specific capacity of 1,950 mAh/g (C/20 rate) based on the total weight of the silicon/carbon composite was reported. In addition, the composite anodes had negligible capacity fade after 100 cycles at 1C rate and excellent rate capability (870 mAh/g at 8C rate). 

Several electrolyte additives have been used to form stable SEI layers and improve cyclability of silicon anodes. Doh et al. [Ill] used 5% 4-fluoroethylene carbonate (FEC) in the electrolyte of 1.0-M LiPFs in EC/DMC/EMC/PC at a volume ratio of 4 3 3 1 when investigating silicon/carbon composites formed by polyaniline carbonization. They found that the addition of FEC to the electrolyte increased the initial discharge capacity of the silicon/carbon composites when compared with the electrolyte without FEC. Choi et al. [112] reported that the... 

Si Q et al (2010) A high performance silicon/carbon composite anode with carbon nanoHber for lithium-ion batteries. J Power Sources 195 1720-1725... 

Yu XI et al (2013) Preparation and electrochemical properties of porous silicon/carbon composite as negative electrode materials. J Inorg Mater. doi 10.3724/SP.J.1077.2013.12672 Yue L et al (2013) Porous silicon coated with S-doped carbon as anode material for lithium ion batteries. J Solid State Electrochem doi 10.1007/s/10008-012-1944-8 Zhang Y, Huang J (2011) Hierarchical nanofibrous silicon as replica of natural cellulose substance. J Mater Chem 21 7161-7165... 

Tsang CK, Kelly TL, Sailor MJ, Li YY (2012) Highly stable porous silicon-carbon composites as label-free optical biosensors. ACS Nano 6 10546... 

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