Porous Silicon and Conductive Polymer Binder Composite Electrode for Lithium Ion Batteries with Stable Cycling

Abstract

Silicon (Si) with porous structure could possibly accommodate the large volume expansion of Si in lithium ion batteries, avoiding fast capacity fading during charge/discharge. Herein, we report a composite electrode made from porous Si with only 5 wt% conductive polymer binder. By limiting the lithiation level, we demonstrate a stable cycled cell with a greatly extended cycle life and high coulombic efficiency beyond 99.5%. Both the morphology study and electrochemical characterization suggest that electrodes are able to accommodate over 50% volume change without any capacity fading during cell operation.