Silicon/carbon composites based on natural microcrystalline graphite as anode for lithium-ion batteries

Abstract

Silicon/carbon composite is considered as one of the most potential anode materials to be commercialized because of silicon’s high specific capacity and carbon’s stability. Natural microcrystalline graphite features abundant resources, low price, and high stability. In consideration of these, it is an ingenious strategy to combine natural microcrystalline graphite with silicon as the anode material of lithium-ion batteries. In this paper, silicon/natural microcrystalline graphite@ carbon layer composites were fabricated by a two-step chemical vapor deposition (CVD) method. In this structure, natural microcrystalline graphite serves as the carbon matrix; silicon grows evenly on the surface and then pyrolytic carbon provides a tight coating. Therefore, the prepared composites deliver a high specific capacity of 560 mA h g−1 after 200 cycles at a current density of 100 mA g−1. This paper provides a potential method for large-scale production and is expected to solve the high-level application problem of natural microcrystalline graphite.