Foamed silicon particles as a high capacity anode material for lithium-ion batteries

Abstract

We report foamed Si particles as a high-performance lithium storage material prepared by a milling-assisted alkaline etching process. The resulting foamed Si electrode showed excellent cycling performance of over 300 cycles with an initial discharge capacity of about 2750 mA h g.

Silicon Anodes for High‐Performance Storage Devices: Structural Design, Material Compounding, Advances in Electrolytes and Binders

“…The design and preparation that from 0D to 2D nano‐silicon anode has largely solved this problem. In order to obtain nanoscale silicon particles, generally, a grinding assisted alkaline etching or a mechanical milling method directly at room temperature may be employed . In addition, silicon nanoparticles prepared to use high energy ball milling techniques also exhibit excellent electrochemical performance .…”

Hollow Graphene as an Expansion-Inhibiting Electrical Interconnector for Silicon Electrodes in Lithium-Ion Batteries

“…Lithium-ion batteries (LIBs), which have contributed to the rapid development of information communication technology, have attracted considerable attention as power sources for electric vehicles and large-scale energy storage systems. − With expanding markets for new battery applications, the demand for LIBs with greater energy density has increased. , To overcome theoretical energy-density limitations in LIBs, numerous electrode materials have been suggested over the past few decades. , Among them, silicon has been identified as a possible replacement for graphite as an anode material because its capacity (3579 mA h g –1 , Li 15 Si 4 ) is about 10 times that of graphite (372 mA h g –1 , LiC 6 ). − However, huge volume changes of silicon during alloying and dealloying reactions with lithium can lead to physical degradation of silicon electrodes in the form of delamination from the current collector and the breakdown of electrical conducting pathways, hindering the practical use of silicon as an anode material for LIBs. − To address the issues associated with volume changes of silicon, multiple strategies have been suggested with respect to the composition and microstructure of silicon-based anode materials. Inactive matrix-employed structures such as SiO x , , Si–C composites, , silicon alloys, , and porous silicon − are typical examples suggested for the purpose of minimizing the volume expansion of Si-based anode materials. For example, silicon–transition-metal nanocomposites such as Si/TiFeSi 2 and Si/Ti 4 Ni 4 Si 7 composite materials suppressed volume change during cycling, which was possible by limiting the amount of Li stored in these composites up to Li 21 Si 8 , not the Li-richest Li–Si phase (Li 15 Si 4 ). , Free voids in silicon-based anode materials can also help regulate volume changes of silicon during cycling. − Properly designed polymeric binders are known to play a key role in solving chronic problems in silicon electrodes by maintaining electrical conduits in silicon electrodes and sustaining the mechanical integrity of the silicon electrode during the charge–discharge process. , Various types of polymeric materials have been suggested to improve the mechanical strength and adhesion of silicon electrodes. , Recently, polymeric materials with intermolecular hydrogen bonds have exhibited remarkable abilities to enhance the structural stability of silicon electrodes, repairing the mechanical damage caused by volume changes of silicon through self-healing chemistry. ,…”

“…Inactive matrix-employed structures such as SiO x , , Si–C composites, , silicon alloys, , and porous silicon − are typical examples suggested for the purpose of minimizing the volume expansion of Si-based anode materials. For example, silicon–transition-metal nanocomposites such as Si/TiFeSi 2 and Si/Ti 4 Ni 4 Si 7 composite materials suppressed volume change during cycling, which was possible by limiting the amount of Li stored in these composites up to Li 21 Si 8 , not the Li-richest Li–Si phase (Li 15 Si 4 ). , Free voids in silicon-based anode materials can also help regulate volume changes of silicon during cycling. − Properly designed polymeric binders are known to play a key role in solving chronic problems in silicon electrodes by maintaining electrical conduits in silicon electrodes and sustaining the mechanical integrity of the silicon electrode during the charge–discharge process. , Various types of polymeric materials have been suggested to improve the mechanical strength and adhesion of silicon electrodes. , Recently, polymeric materials with intermolecular hydrogen bonds have exhibited remarkable abilities to enhance the structural stability of silicon electrodes, repairing the mechanical damage caused by volume changes of silicon through self-healing chemistry. , Suppressing the dimensional changes in silicon electrodes was also possible by providing the pores in silicon electrodes using a pore generator such as triethanolamine and polystyrene. , Pores formed inside a silicon electrode absorb the expansion of silicon upon lithiation, thereby suppressing mechanical degradation of the silicon electrode. However, additional treatment, for example, thermal vaporization of a polymeric pore generator at elevated temperature, is needed to create pores in silicon electrodes.…”

Real‐Time Dilation Observation of Si‐Alloy Electrode Using Thermally Treated Poly (Amide‐Imide) as a Binder for Lithium Ion Battery

“…[5][6][7] Mechanical stress caused by repeated volume changes results in the degradation of Si, as well as electrical contact loss between Si, conductive agent and current collector in the electrode, eventually showing capacity fading during cycling. [8][9][10] To address this technical issue of Si-based electrodes, various material strategies such as modifying the structure and composition of Si including nano-structured Si, [11][12][13] active Si/inactive material composites, [14][15][16][17] and porous Si-based material [18][19][20][21] have been suggested.…”