PVA generated carbon-coated natural graphite anode material for enhanced performances of lithium-ion batteries

The surface modification of electrode active materials has attracted considerable attention as a straightforward approach to enhance properties of lithium-ion batteries. In this study, we present a facile method for preparing surface-modified natural graphite (NG) by uniformly mixing NG with polyvinyl alcohol (PVA) and subsequent carbonization to obtain carbon-coated NG as an anode material for lithium-ion batteries. The optimal performance was achieved when the mass ratio of PVA to NG is 1:5. The carbon-coated NG anode material demonstrated a stable discharge specific capacity of about 400 mAh g-1 and excellent cycle retention (72.8% after 100 cycles at 0.2 C), showing an average capacity of 24% that is higher than that of NG. Furthermore, carbon-coated NG also presented superior rate performance compared with pure NG. The concept of coating NG with PVA-derived carbon proposed in this paper paves the way for innovative high-performance lithium-ion battery anode materials.