Due to its low average voltage, low voltage hysteresis, good rate capability, low irreversible capacity, low volume expansion during lithiation causing excellent cycle life, graphite has been the material of choice as anode material .
However, the low theoretical specific capacity limits the application potential of graphite anodes. With its high theoretical specific capacity, silicon is the most promising anode material. However, the use of pure silicon is severely restricted by its mechanical behavior during charge/discharge cycling. Crystallization effects and massive volume changes during cycling seriously limit the cycle life of battery cells with Silicon as main component . Therefore, Silicon/graphite blends seem to be the preferred route towards high energy anode formulations with relevant life times.
In this context it is essential to understand the interplay between the various components of the blend electrodes for optimized performances, which is addressed in the current publication.
Different industrially available graphites (KS6, KS6L. MCMB, LFP2, ECC Graphit) and a Silicon alloy material were used for anode preparation in order to investigate their structural morphologies and electrochemical performance of the resulting electrodes. The electrodes were tested in coin cell assemblies and charged and discharged at various rates. The morphologies of fresh and aged electrodes were investigated by means of optical and electron microscopy. Furthermore the volume changes of cells were monitored in order to relate it with the morphological appearance, porosity and graphite type.
 M. N. Obrovac and V. L. Chevrier, “Alloy Negative Electrodes for Li-Ion Batteries,” Chemi. Rev., pp. 11444–11502, 2014.
 W. J. Zhang, “A review of the electrochemical performance of alloy anodes for lithium-ion batteries,” J. Power Sources, vol. 196, no. 1, pp. 13–24, 2011.