Walnut-structure Si-G/C materials with high coulombic efficiency for long-life lithium ion batteries.

ABSTRACT: Nano-sized silicon is a potential high energy density anode material for lithium ion batteries. However, the practical use of a nano-Si anode is still challenging due to its low coulombic efficiency, poor scalability and cycling stability. Herein, a Si/graphite/carbon (Si-G/C) composite with a core-shell structure was fabricated by a facile two-step chemical process, stirring-evaporating followed by heat treatment. The composite structure consists of a graphite core, coated first by silicon and then amorphous carbon, which was decomposed by pitch. The as-prepared Si-G/C composite anode demonstrates a first cycle capacity of about 650 mA h g^-1, over 90% coulombic efficiency, and high capacity retention of 96.7% after 50 cycles. When paired with a commercial NCA cathode, superior

SUBMITTER: Xiao C 

PROVIDER: S-EPMC9083468 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature