Novel architecture of composite electrode for optimization of lithium battery performance

We show that the polymeric binder of the composite electrode may have an important role on the lithium trivanadate Li1.2V3O8 electrode performance. We describe a new tailored polymeric binder combination with controlled polymer–filler (carbon black) interactions that allows the preparation of new and more efficient electrode architecture. Using this polymeric binder, composite electrodes based on Li1.2V3O8 display a room temperature cycling capacity of 280 mAh g−1 (C/5 rate, 3.3–2 V) instead of 150 mAh g−1 using a standard-type (poly(vinylidene fluoride)–hexafluoropropylene (PVdF–HFP) binder) composite electrode. We have coupled scanning electron microscopy (SEM) observations, galvanostatic cycling and electrochemical impedance spectroscopy in order to define and understand the impact of the microstructure of the composite electrode on its electrochemical performance. Derived from these studies, the main key factors that provide efficient charge carrier collection within the composite electrode complex medium are discussed.