Interface Engineering of Silicon/Carbon Thin-Film Anodes for High-Rate Lithium-Ion Batteries

Abstract

Silicon is one of the most promising alternative active materials for next-generation lithium-ion battery (LIB) applications due to its advantage of high specific capacity. However, the enormous volume variations during lithiation/delithiation still remain to be an obstacle to commercialization. In this work, binder-free pure silicon and silicon/carbon (Si/C) multilayer thin-film electrodes, prepared by scalable one-step magnetron sputtering, are systematically investigated by an interlayer strategy. Herein, we present a rationally structural modification by an amorphous carbon film to enhance the electrical conductivity, mechanical integrity, and electrochemical performance of Si film-based LIBs. Therefore, to maintain the consistency of the direct-contact layer with the electrolyte and current collection, symmetrical Si/C/Si and Si/C/Si/C/Si/C/Si electrodes are deliberately designed to study the influence of embedded carbon. An anode with a carbon content of 10.38 wt % yields an initial discharge specific capacity of 1888.74 mAh g–1 and a capacity retention of 96.82% (1243.56 mAh g–1) after 150 cycles at a high current density of 4000 mA g–1. It also shows that the best rate capability remains 96.0% of the initial capacity in the 70th cycle. At last, three mechanisms are proposed for an in-depth understanding of the interface effect. This work offers a new perspective scheme toward Si/C-based LIBs with a capability of high rate and high energy density.

Recent Developments of Nanomaterials and Nanostructures for High‐Rate Lithium Ion Batteries

“…-tuneable composition and structure -large specific surface area -tailorable porosity -disintegration during cycling -poor electrical conductivity -understating the influence of the porosity and distribution of the pores in the MOF framework -creating MOF-based nanocomposite with conductive additives [257], [259] Si/C nanostructures -excellent long-term stability -high specific storage capacity -high electrical conductivity -simply mixing carbon-based materials with si particles leads to serious aggregation -developing facile synthesis route for ultrathin 2D siligraphenes with high level of purity and uniformity -regulating the surface states of Si in the preparation of Si/C [260], [262] organics (anode)…”

“…[261] Recently, Si/C multilayer thin-film anodes without any binders and additives were prepared by magnetron sputtering deposition. [262] By modifying the stack structure of the sandwiched thin-film anodes, it was revealed that diffusion kinetics of lithium ions could be improved by local electric field created by Li x Si alloys at the interface, dangling bonds and/or defects between the multilayers. In an optimised condition, a capacity of 1244 mAh g À 1 at 1 C (4 A g À 1 ) after 150 operating cycles was achieved.…”

“…In an optimised condition, a capacity of 1244 mAh g À 1 at 1 C (4 A g À 1 ) after 150 operating cycles was achieved. [262] In addition to the layered structure, a compact graphite/Si/C with a core-shell architecture was developed by Zhao et al, in which the size and oxidation states of Si nanoparticles were controlled by sand milling. [263] By tuning the size and surface states of Si particles, volume variation of the electrode can be mitigated during operation.…”

Insight into the Origins of Figures of Merit and Design Strategies for Organic/Inorganic Lead‐Halide Perovskite Solar Cells

“…The degradation damage phenomenon is also present in other photoelectric devices. [203] Typical structural damage is widespread in complete PSCs, which include pores and point contacts between the electrode/ underlying layer, cracks/voids in transport and active layers, and in the detachment or discontinuity between the interfaces of functional layers due to heat-stressed, ion-migration, or halide-corrosion effects. A typical landform of a cross-sectional PSC is shown in Figure 6f.…”

Theoretical Study of a New Porous 2D Silicon-Filled Composite Based on Graphene and Single-Walled Carbon Nanotubes for Lithium-Ion Batteries

“…Silicon-based materials are considered as one of the most potential anode materials for LIB because of their high theoretical capacity of 4200 mAh•g −1 , for Li4.4Si [1][2][3][4][5][6][7][8][9][10]. There are various types of Li-Si intermetallic states.…”