Improving the electrochemical properties of SiO@C anode for high-energy lithium ion battery by adding graphite through fluidization thermal chemical vapor deposition method

Abstract

A series SiO/graphite@C (SGC) composites electrode are successfully prepared by a fluidization thermal chemical vapor deposition (FTCVD) route in a kilogram-scale fluidized bed CVD equipment. This strategy can avoid the effect of particle agglomeration on carbon coating during heating reaction. The phase composition, element distribution, particle appearance and electrochemical properties of the as-obtained SGC composite is investigated in detail. The charge specific capacity of SGC-37 is close to 799.1 mAh g−1 after 100 cycles at 200 mA g−1. The SGC-37 shows a high capacity retention of 93.7% after 100 cycles, which much higher than that of SiO, SiO@C, SGC-73 and SGC-55 (the retention rates are 26.3%, 56.8%, 75.5% and 89.6%, respectively). The reason is mainly because improve Li ion diffusion coefficient, shorten transfer pathway of Li ion and ease to the volume change of SiO due to surface carbon coating and graphite addition. The FTCVD methods is not only an efficient method to prepared SGC anode, but also is may easy to apply to surface carbon coating of another particle material.