Mechanochemical synthesis of Si/Cu3Si-based composite as negative electrode materials for lithium ion battery.

ABSTRACT: Mechanochemical synthesis of Si/Cu3Si-based composite as negative electrode materials for lithium ion battery is investigated. Results indicate that CuO is decomposed and alloyed with Si forming amorphous Cu-Si solid solution due to high energy impacting during high energy mechanical milling (HEMM). Upon carbonization at 800?°C, heating energy induces Cu3Si to crystallize in nanocrystalline/amorphous Si-rich matrix enhancing composite rigidity and conductivity. In addition, residual carbon formed on outside surface of composite powder as a buff space further alleviates volume change upon lithiation/delithiation. Thus, coin cell made of C-coated Si/Cu3Si-based composite as negative electrode (active materials loading, 2.3?mg?cm-2) conducted at 100?mA?g-1 performs the initial charge capacity of 1812?mAh?g-1 (4.08 mAh cm-2) columbic efficiency of 83.7% and retained charge capacity of 1470?mAh?g-1 (3.31 mAh cm-2) at the end of the 100th cycle, opening a promised window as negative electrode materials for lithium ion batteries.

SUBMITTER: Hou SC 

PROVIDER: S-EPMC6107536 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature