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Since decades, attempts have been made to incorporate silicon into Li-ion battery anodes in order to improve the energy density beyond the theoretical limit of graphite (372 mAh/g).1 These efforts have frequently been hampered by poor cycling stability resulting from the substantial volume change of silicon during lithiation/de-lithiation cycles. It has recently been demonstrated that careful selection of conductive graphite and carbon black additives leads to significantly reduced aging phenomena in silicon-based composite electrodes.2 Electrochemical results will be presented for an optimized surface-modified carbon matrix that leads to highly favorable cycling stability in combination with commercially available silicon-based active materials. Bulk and surface properties of these composite electrodes will be discussed. References: 1a) Besenhard, J. O.; Komenda, P.; Paxinos, A.; Wudy, E. Solid State Ionics 1986, 18-19 (2), 823; b) Wilson, A. M.; Dahn, J. R. J. Electrochem. Soc. 1995, 142, 2, 326; c) Son, I. H.; Park, J. H.; Kwon, S.; Park, S.; Rümmeli, M. H.; Bachmatiuk, A.; Song, H. J.; Ku, J.; Choi, J. W.; Choi, J.; Doo, S.; Chang, H. Nature Commun. 2015, 6, 7393. 2a) Du, Z.; Dunlap, R. A.; Obrovac, M. N. J. Electrochem. Soc. 2014, 161 (10), A1698; b) Petibon, R.; Chevrier, V. L.; Aiken, C. P.; Hall, D. S.; Hyatt, S. R.; Shunmugasundaram, R.; Dahn, J. R. J. Electrochem. Soc. 2016, 163 (7), A1146. |
