Preparation and Performance of In Situ Carbon-Coated Silicon [email protected]@carbon Microspheres Composite Anode Material for Lithium-Ion Batteries

Lingtong Meng,2,3

Chunping Hou,1,2*Email

Jiao Hou,3

Haidong Xie,1

Zeyu Yue,1

Hui Lu,1,2

Shaolin Yang1,2 

Bolin Gong3*Email

1College of Materials Science and Engineering, North Minzu University, Yinchuan, Ningxia, 750021, China

2Ningxia Silicon Target & Silicon Carbon Anode Material Engineering Technology Research Center, Yinchuan, Ningxia, 750021, China

3College of Chemistry and Chemical Engineering, North Minzu University, Yinchuan, Ningxia, 750021, China

Abstract

Silicon monoxide (SiO)@[email protected] microspheres (CMSs) composites with core-shell structures were prepared by the hydrothermal method combined with subsequent heat treatment, using glucose as a carbon source. SEM analysis showed that this process resulted in SiO particles that were uniformly coated by the pyrolytic carbon layer and surrounded by CMSs. With increasing quantities of glucose added, the cycle performances of [email protected]@CMSs composites were improved remarkably, with a moderate amount of glucose addition resulting in the greatest performance. Specifically, among the four composite samples, [email protected]@CMSs-2 had the best cycle performance, delivering a high initial capacity of 1024.5 mAh g-1 at 50 mA g-1 and a specific capacity of 638.6 mAh g-1 after 60 cycles at a current density of 200 mA g-1. Even at a current density of 1.5 A g-1, it was still able to deliver a reversible capacity of about 450 mAh g-1. This was attributed to the formation of mesoporous carbon coating and CMSs by the hydrothermal synthesis of glucose. The mesoporous pyrolytic carbon coating of glucose increases the lithium ion diffusion rate and improves the conductivity of the material. At the same time, the volume expansion of the material during lithiation/delithiation is restrained by carbon coating and the CMSs serve as a buffer to alleviate volumetric stress. Therefore, [email protected]@CMSs-2 is a stable material with improved cycle performance.

Preparation and Performance of In Situ Carbon-Coated Silicon Monoxide@C@carbon Microspheres Composite Anode Material for Lithium-Ion Batteries