Although lithium ion batteries are predominant in battery storage technologies, their specific capacity that falls short of gasoline can still be further improved. Silicon is considered as a promising anode material due to its high specific capacity (~3500 mAh/g). However, this high specific capacity leads to drastic volume expansion, which undermines the cycling stability of electrode. In this study, we incorporated lignin as carbon precursor in recycled silicon to form a carbon/silicon composite material. The lignin was first dissolved in alkline solutions to form a well covering layer around silicon particle. This composite material was then pyrolyzed at 600 °C under argon atmosphere with or without conductive carbon KS6. The results indicated conductive carbon KS6 can serve as a seed in the pyrolysis process and the composite with KS6 provided a stable cycle life. In our cycling test, the initial specific capacity of the electrode with KS6 was 714.6 mAh/g, and, after 50 cycles, it retained up to 90% of the initial capacity at a high charging rate of 700 mA/g (~1C). With the excellent specific capacity retention and fast charging properties, this composite shows a great potential to be practically applied in future energy storage applications.

Conductive graphite incorporated carbon/silicon composites as negative electrode materials for lithium ion cells

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.