Memory effect highlighting in silicon anodes for high energy density lithium-ion batteries

Abstract: A memory effect occurring on silicon electrodes during lithium insertion/deinsertion was revealed by means of electrochemical characterizations. The reversible capacity fading is triggered when the electrodes are cycled between Li-rich compositions, which are actually achieved in selected conditions (current density, voltage window, electrode thickness). It is correlated with a structural evolution of Li-rich alloys, i.e. the crystallization of Li15Si4 or the probable ordering of other Li-rich phases. It should be avoided in Li-ion practical cells by an appropriate cell design. [Copyright &y& Elsevier]