writer：Juan Jin, Zhi-qiang Shi, Cheng-yang Wang
keywords：Polyacrylonitrile，Hard carbon microspheres ，Li-ion batteries
source：期刊
specific source：Solid State Ionics.
Issue time：2014年

A hard carbon microsphere (HCS) material with a uniform walnut kernel structure was prepared using polyacrylonitrile (PAN) asa a carbon precursor by a stabilization–carbonization method. The PAN–HCS preserves the original ellipsoidal shapes of natural polyacrylonitrile granules. Structural analysis shows that PAN–HCS is a kind of disordered carbon containing micropores and graphite-like micro-crystallites. The effects of heat-treatment temperature varying from 800 to 1500 °C on electrochemical performance were systemically studied. PAN–HCS–1250 obtained at 1250 °C as a negative material for lithium-ion batteries exhibits a reversible capacity of about 350 mAh g? 1 at 20 mA g? 1 with an excellent rate capability and cycling stability.