A reactive molecular dynamics simulation of the Lithiated Silicon/Carbon composite anode in Lithium ion batteries
Alireza Ostadhossein (Pennsylvania State University), Adri van Duin (Pennsylvania State University)
Lithium ion batteries: When Chemistry meets Mechanics
Tue 10:45 - 12:15
Salomon 003
Lithium ion batteries (LIBs) are widely used as power devices for portable electronics. For more demanding applications such as powering electric vehicles, LIBs with radically improved energy density and power capability are highly desirable. Silicon, owing to its large theoretical energy density (4200 mA h g-1) becomes one of the most promising anode materials for the next-generation LIBs, as it has a Li storage capacity about 10 times larger than that of the carbonaceous anodes used in commercial LIBs. However, Li insertion/extraction cycling induces huge volumetric expansion and stress inside the electrodes, causing fast dissociation or cracking. A Molecular Dynamics (MD) simulation using the ReaxFF reactive force field has been performed to illustrate the possibility of using carbon nanotubes (CNTs) for the SiNW reinforcement to control the volume expansions. The atomistic understanding of stress phenomena in the SiNW encapsulated within the CNT will provide an effective way to avoid the pulverization in Si anodes of LIBs.