Advanced hybrid-structured anodes for lithium-ion batteries

Two‐Layer Silicene on the SiC Substrate: Lithiation Investigation in the Molecular Dynamics Experiment

“…In both cases, i. e., for both vertical and horizontal intercalations of lithium, their presence above the centers of the six-membered Si rings is the most probable localization of Li atoms in the area of silicene sheets. We observed the similar effect in the behavior of lithium atoms in our previous calculations, [23][24][25][26][27][28][29][30] when the silicene channel located on different metal substrates (Ag, Ni, Al, Cu) was horizontally filled with lithium. Quantum-mechanical calculations show that for the singlelayer free-standing silicene, the preferred location of the lithium adatom is above the center of the six-membered Si ring (hollow site) with the binding energy of E b = 2.23 eV.…”

“…To organize the effect of the field on the ions, the corresponding component of the force was added at each time step to push the ions in the required direction. We selected the field value empirically in the MD calculations when lithium intercalation in the silicene channels on metallic [22][23][24][25] and nonmetallic [27,30,37] substrates was simulated. The used value of the electric field ensured the entry of the lithium ion into the channel, its movement along the channel, and fixation in the channel during 1 million time steps, i. e., 100 ps.…”

“…[39,40] It has successfully proven itself in modeling of two-dimensional systems. [22][23][24][25][26][27] The interactions between Si atoms of different silicene sheets, as well as between Si atoms of silicene and substrate atoms (C or Si) were described using the Morse potential with parameters reported in. [41] The Lennard-Jones potential was applied to describe the interactions between LiÀ Li, LiÀ Si, LiÀ C and parameters provided in.…”

“…Molecular dynamics experiments have shown that silicene (when it is located on different metal substrates (Ag, Ni, Cu) as well as on graphene) can remain stable after a single lithiation/ delithiation cycle. [22][23][24][25][26] Silicene is not destructed and returns to its original volume. In this case, defect-free silicene can have more significant stresses and a lower capacitance than silicene modified with vacancy defects.…”

An Ab Initio Study of Lithization of Two-Dimensional Silicon–Carbon Anode Material for Lithium-Ion Batteries

“…A high theoretical capacity of silicon (4200 mAh•g −1 ) and a suitable operating voltage make it one of the most promising anode materials for a LIB [2]. However, bulk crystalline or amorphous silicon cannot serve as a good anode material for LIB because of the large (up to 300%) volume change during cycling and low electrical conductivity [3]. Increasing the electrical conductivity of the electrode facilitates a fast LIB charging process.…”