Silicon-based Anode Materials Research Articles

Boosting the initial coulombic efficiency for SiO anodes through component controlling and microcrystalline size limiting regulated by carbon layer

Silicon-based anode materials are attracting considerable attention due to their high specific capacity for further improving the energy density of lithium-ion batteries (LIBs). Among them, silicon monoxide (SiO) has a good balance between high specific capacity and cycling lifespan, which is increasingly valuable in the market of lithium-ion batteries. However, its poor initial coulombic efficiency (ICE) severely impedes the commercialization of SiO. Although prelithiation and surface carbon coating are considered effective methods to reduce irreversible consumption during the initial lithiation process, the synergistic relationship between prelithiation and carbon coating has not yet been confirmed. Herein, we used LiH as solid-phase prelithiation reagent and acetylene as carbon source for carbon coating to improve the ICE as well as cyclic stability of SiO anode. Results show that the process sequence of pre-lithiation and carbon coating has a significant impact on regulating the internal lithium silicate components and the microcrystalline size of silicon and lithium silicates. A prioritizing carbon layer coating subsequent to prelithiation can achieve physical barrier effect, effectively regulating the prelithiation reaction process to refine the internal silicon and lithium silicate crystal material, and avoiding the formation of lithium-poor Li2Si2O5 phase. The obtained SOC-P sample exhibits a superior ICE of 88.1 % and a stable irreversible capacity of 842.9 mAh/g after 200 cycles. This work provides practical reference idea for solving the low initial efficiency issue of SiO anode material.

Reducing the SiOx layer on Si/reduced graphene oxide enables fast and reversible lithium-ion storage capability for lithium-ion batteries

To investigate whether the presence of a SiOx layer affects the electrochemical performance of silicon-based materials, particularly the silicon-carbon anode material, a facile and scalable process involving HCl etching, annealing, and HF etching was employed to synthesize a silicon-carbon composite (Si/SiOx-rGO) and reduce the SiOx layer content at the silicon-carbon interface to obtain a Si-rGO composite. Experimental results demonstrate that this method effectively reduces the SiOx content in the composite. By decreasing the SiOx layer content, the Si-rGO composite exhibits the specific capacities of 758.3 mAh g−1 at 3 A g−1 and 557 mAh g−1 at 5 A g−1. After 200 cycles at 2 A g−1, it still retains a capacity of 930.8 mAh g−1. These findings offer comprehensive insights into the SiOx layer at the silicon-carbon interface, thereby enhancing the application of silicon-based anode materials.

Advanced Micro/Nanostructure Silicon-Based Anode Materials for High-Energy Lithium-Ion Batteries: From Liquid- to Solid-State Batteries

Advanced Micro/Nanostructure Silicon-Based Anode Materials for High-Energy Lithium-Ion Batteries: From Liquid- to Solid-State Batteries

Structures and properties of carbon-doped silicon as anode material for lithium ions battery: A first-principles study

Anode materials for lithium ions battery have been much less investigated than the cathode materials. Recently, silicon-based anode materials have attracted attentions for its high theoretical capacity. In the present work, the structures and properties of carbon doped silicon as the anode materials of lithium ions battery were investigated by first-principles method. In the doping concentration range from 1.56 % to 15.6 %, the results show that the stronger Si–C covalent bond leads to a higher bulk modulus of the carbon-doped silicon structures. The band gap of the doped structure decreases with increased doping concentration. The volume expansion can be suppressed by the doping of the carbon atom, and the structures with higher carbon concentrations had a better suppression effect. Meanwhile, the lithium diffusion energy barrier increases with the carbon doping concentration.

Innovative design of silicon-core mesoporous carbon composite for high performance anode material in advanced lithium-ion batteries

Silicon is widely recognized as an exceptionally auspicious anode material for lithium−ion batteries due to its remarkable specific capacity, suitable operational potential, and ecologically innocuous characteristics. This study presents a novel silicon@void@FC (fibrous carbon) composite anode material for lithium-ion batteries. Utilizing a one-step synthesis approach, the resulting hollow core–shell structure, combined with a mesoporous carbon shell, demonstrates exceptional electrochemical performance. The Si@Void@FC electrode exhibits remarkable cycle stability and rate performance, maintaining structural integrity over 500 cycles without observable degradation. The outer carbon shell acts as a protective layer and accommodates silicon volume expansion during cycling, preventing excessive contact with the electrolyte. The rich mesoporous structure facilitates efficient lithium-ion diffusion, enhancing lithiation and delithiation processes. The simplified one-step synthesis method further streamlines the preparation process, eliminating the need for complete silica template formation. This innovative Si@Void@FC composite material holds promise for advancing lithium-ion battery technology, addressing challenges associated with silicon-based anode materials, and offering insights into the design and synthesis of high-performance energy storage materials.

Enhancing the cycling stability of commercial silicon nanoparticles by carbon coating and thin layered single-walled carbon nanotube webbing

Silicon-based anode materials are considered as the most attractive alternatives to traditional graphite anodes, thereby advancing the evolution of new-generation lithium-ion battery technology. However, the inadequate electrical conduction of silicon-based materials, along with severe volume expansion during charging and discharging processes, limits their further technological applications. Herein, a dual-layer carbon shell configuration is designed to efficiently alleviate the substantial volumetric expansion of silicon during cycles, while simultaneously improving the efficiency of both electron and lithium ions. The effectiveness of this layered buffering approach is credited to the networked structure of outer single-walled carbon nanotubes (SWCNTs) layer, which is firmly attached to the inner carbon shell's surface. The modified structure not only elevates the level of electrical conduction, but also significantly reduces the internal stress due to silicon's expansion. The developed Si@C@SWCNT electrode materials exhibit high capacity of 1267.3 mA h g−1 after 500 cycles at 1 A g−1, and sustains an elevated rate capacity of 863 mA h g−1 at 8 A g−1. This study highlights the enormous potential of Si@C@SWCNT composites for use in lithium-ion batteries and provides new perspectives for further exploration and utilization of silicon-carbon anodes.

Comparison of commercial silicon-based anode materials for the design of a high-energy lithium-ion battery

Comparison of commercial silicon-based anode materials for the design of a high-energy lithium-ion battery

FIRST-PRINCIPLES COMPUTATIONAL INSIGHTS INTO SILICON-BASED ANODE MATERIALS: RECENT PROGRESS AND PERSPECTIVES

Silicon-based material is one of the most promising substitutes for commercial graphite anodes for the next generation lithium-ion batteries due to its extremely high theoretical capacity. However, the huge volume changes during the charging and discharging processes will cause rapid capacity decay and a short cycle life. Developing novel silicon-based materials requires a fundamental understanding of their properties. However, in many cases, the present experiments are incapable of completely mimicking real battery-operation conditions, and detailed information about the electrochemical mechanisms and ion and electron kinetic transport at the electrode/electrolyte interface is still ambiguous due to their complexity. First-principles calculations have become an effective method for predicting and interpreting the characteristics of electrode materials, understanding the electrochemical mechanisms at the atomic scale and delivering rational design strategies for electrode materials. In this review, the first-principles calculations of silicon-based anode materials in recent years, based on different modification strategies, are summarized. First, we introduce the diffusion kinetics of lithium ions in silicon and the mechanism of structure changes during the lithiation process. Then, typical examples of novel Si-based anodes, including 2D nanomaterials, silicide materials and coating materials based on theoretical predictions, are presented. Finally, we provide perspectives and future directions of first-principles calculations on Si-based anodes.

In Situ Copper Coating on Silicon Particles Enables Long Durable Anodes in Lithium-Ion Batteries.

Addressing the significant obstacles of volume expansion and inadequate electronic conductivity in silicon-based anode materials during lithiation is crucial for achieving a long durable life in lithium-ion batteries. Herein, a high-strength copper-based metal shell is coated in situ onto silicon materials through a chemical combination of copper citrate and Si-H bonds and subsequent heat treatment. The formed Cu and Cu3Si shell effectively mitigates the mechanical stress induced by volume expansion during lithiation, strengthens the connection with the copper substrate, and facilitates electron transfer and Li+ diffusion kinetics. Consequently, the composite exhibits a reversible specific capacity of 1359 mA h g-1 at 0.5 A g-1 and maintains a specific capacity of 837 mA h g-1 and an 83.5% capacity retention after 400 cycles at 1 A g-1, surpassing similar reports on electrochemical stability. This facile copper plating technique on silicon surfaces may be used to prepare high-performance silicon-based anodes or functional composites in other fields.

Recent progress and challenges in silicon-based anode materials for lithium-ion batteries

This review highlights the importance of silicon-based anodes in lithium-ion batteries, emphasizing their improved performance through modifications involving binders, coatings, composites, and electrolytes.

Two step pyrolysis synthesis method of graphite-enhanced Nano-Si/Pitch composite as long cycle life anode for lithium-ion batteries

Energy storage devices have become the dominant power source in various fields due to their capacity, lifespan, and eco-friendliness. However, there is a need to develop new energy storage devices with higher energy and power density to meet increasing energy demands. Silicon-based anode materials have considerable potential for developing long-lasting, high-capacity energy storage devices, specifically lithium-ion batteries. However, the practical use of these batteries faces challenges like significant volume variations, silicon instability during charging and discharging, and restricted conductivity. This work used silicon nanoparticles from waste industrial solar cells and mixed them with pitch derived from coal tar in a tetrahydrofuran (THF) solvent to form a homogenous Si@Pitch nanocomposite. Pitch-derived carbon helps hold the silicon particles together, reducing the detrimental effects of volume expansion. It acts as a matrix that accommodates the structural changes in silicon during lithiation and delithiation. The Pyrolyzed Si@Pitch-2:1 nanocomposite electrode developed through an efficient two-step pyrolysis technique demonstrated outstanding performance. When charged at a rate of 500 mA·g−1 over 200 cycles, it showed a high discharge capacity of 1524 mAh·g−1, with an average coulombic efficiency of 99.8% and a discharge capacity retention of 75.7%. Combining silicon nanoparticles and pitch derived from recycled industrial waste contributes to the impressive results. This efficient synthesis method can improve the anode materials used in lithium-ion batteries.

Improving SiOx Electrode Performance in Pressurized Pouch Cells with a Ceramic Coated Separator

The global electric vehicle (EV) landscape, driven by environmental concerns, has propelled the demand for high-capacity battery materials. Silicon-based anode materials have emerged as promising candidates due to their remarkable capacity. However, the inherent challenge lies in their substantial volume expansion during operation, exceeding 300%, which causes structural instability within the electrode.To counteract this issue, a direct compression method is employed to mitigate the anode's volumetric expansion, ensuring sustained adhesion between active materials and current collectors. This approach promotes consistent electrical connectivity and augments capacity retention. Nevertheless, excessive pressure can detrimentally affect separators with limited mechanical resilience, resulting in pore constriction. This constriction impedes the efficient flow of electrolytes between the separator and electrode, leading to premature lithium depletion.In our study, we compressed SiOx electrodes using Ceramic Coated Separator (CCS). CCS's unique combination of mechanical reinforcement, improved wetability, and enhanced ionic conductivity played a pivotal role, ultimately contributing to the overall improvement in electrode performance. We employed digital-twin simulations, utilizing the Finite Volume Method (FVM), to investigate the influence of CCS on various aspects. Digital-twin simulations involve creating a computational replica of the real object's geometry, allowing us to replicate its behavior and characteristics in a virtual environment, thereby enabling a detailed and accurate assessment of CCS effects. This included analyzing the enhancement of mechanical properties, such as the evaluation of von Mises stress and effective stiffness. Furthermore, we explored how CCS impacted the deformation of separators under pressure and closely monitored the movement of lithium ions within them.The findings underscore the successful integration of CCS into SiOx electrodes, resulting in a substantial improvement in life and performance under pressure conditions. This research contributes valuable insights to the advancement of battery technology, particularly in the context of EVs, by addressing critical challenges associated with silicon-based anode materials.

Accelerating the Development of New Silicon-Based Anode Materials

In this work we have demonstrated the feasibility of using thin film systems as a steppingstone to accelerate the development of commercially relevant silicon-based anode materials for Li-ion batteries. Understanding new materials in conventional particle-based electrode systems is often complex. Lithium and electrolyte interact not only with the active material particles, but also with the different supporting components of the electrode, leaving it difficult to directly assess the electrochemical contribution of the active material. This is further complicated by the electrochemical behavior of such electrodes also being strongly dependent on processing conditions, like casting and drying procedures. Additionally, it is often also a challenge to synthesize such materials in particle form with the required chemical composition and monodispersity in the first place. Therefore, it would be highly beneficial to study and screen new anode materials without having to assume and assess these different factors. That is of particular importance during the optimization stage of the chemical composition for the active material, for which a significant number of samples is typically needed. Thus, evaluating the material in a thin film system is a simple and reproducible method of determining a material’s potential as a future anode material.Such thin films of active materials can reliably be made with a large range of thicknesses, compositions, element combinations and coatings, using multiple flexible and reproducible thin film deposition techniques available. In the present work, we have investigated silicon-based materials made by PECVD and sputtering: pure silicon and sub-stoichiometric versions of silicon nitride, silicon carbide, and silicon phosphide (SiNx, SiCx, SiPx). For evaluation of the applicability of the thin film model system, in several cases we have also compared the results to particles of the same material with similar chemical composition synthesized via a free space CVD process [1].Preliminary evaluation shows good agreement between results for thin film systems compared to what is known for particles of the same material. SiNx particles show good agreement with thin film results where a high nitrogen content decreases the capacity, while increasing the stability due to the formation of a stabilizing matrix around the active silicon [2]. Differences in the differential capacity analysis of similar materials in particle and thin film forms demonstrates the greater complexity in interpreting the data from the more intricate particle-based systems. SiCx is known to react in a similar fashion as SiNx where its coulombic efficiency and capacity decreases with increasing carbon-content, while its stability has been seen to increase due to a similar stabilizing matrix [3]. Reference s : [1] H. F. Andersen et al., ECS Trans., vol. 62, no. 1, pp. 97–105, 2014.[2] A. Ulvestad et al., ACS Nano, vol. 15, no. 10, pp. 16777–16787, 2021.[3] X. D. Huang et al., RSC Adv., vol. 8, no. 10, pp. 5189–5196, 2018.

In-Situ Convertible Amorphous Silicon Nitride (SiNx) Anode: Resolving the Long-Term Cyclic Instability of Silicon

Silicon (Si) has shown its promises as anode material for next-generation high-energy lithium-ion batteries (LIBs) due to its high theoretical capacity1. However, its practical application has been impeded by the severe cyclic instability caused by a large volume change during (de) lithiation. Recently, a new family of silicon-based anode materials called “in-situ convertible-type anode materials” has emerged to resolve the cyclic instability of silicon.2,3 This family includes sub-stoichiometric oxides, nitrides, and carbides of silicon (SiAx, where A = N, C, O). The working principle of these materials follow two mechanisms: (1) irreversible conversion and (2) reversible alloying/dealloying. During initial lithiation, the conversion reaction occurs, forming Si-Li nanodomains inside a stable Li-conductive matrix denoted as LiySixA (A=N, C, O). In the subsequent cycles, the Si-Li nanodomains reversibly alloying/dealloying with Li, while the Li-conductive matrix ensures stable cycling and good rate capability. Such composition mitigates the challenges associated with Si’s large volume change ensuring long-term cyclic stability.In this study, we demonstrate our approach on the development of silicon-rich, sub-stochiometric, amorphous silicon nitride (SiNx) nanoparticles, as an in-situ convertible-type anode material and its long-term cyclic performance for LIBs. In this approach, the SiNx nanoparticles are produced via the decomposition of silane gas in the presence of ammonia using an industrially scalable, free space reactor (FSR), which is developed and customized in our research institute (IFE) (Fig. 1a). Proper proportions of silane and ammonia gases are introduced into the reactor, leading to the nucleation and growth of SiNx nanoparticles. The synthesized SiNx nanoparticles exhibited Si-rich domain and amorphous structure with particle size between 100 nm - 200 nm (Fig. 1b), as confirmed by SEM, TEM and XRD characterizations. The presence of nitrogen in silicon dominated composition is revealed by energy dispersive electron spectroscopy (EDS) and Fourier-transform infrared spectroscopy (FTIR). The scalability and reproducibility of the FSR synthesis method makes it a promising approach for the industrial production of SiNx for advance anode materials for LIBs.The electrochemical performance of the synthesized SiNx anode is evaluated by galvanostatic cycling and electrochemical impedance spectroscopy. The electrochemical performance of the SiNx performed on the electrodes with the active mass loading of 0.987 mg/cm2 and cycled at C/5 rate has preserved its capacity about 852 mAh/g after around 600 cycles. As seen from Fig. 1c, the improved cyclic stability of the SiNx compared with pure silicon indicates that the Li-conductive matrix plays crucial role in stabilizing the anode. The authors emphasize the need for further investigation and collaboration, particularly in advance characterization, to better understand the composition and mechanisms of the Li-conductive matrix in the SiNx anode. Such detailed understanding can significantly benefit the conversion-type anode materials for their widespread use in future LIB technologies.References Zuo, X., Zhu, J., Müller-Buschbaum, P. & Cheng, Y.-J. Silicon based lithium-ion battery anodes: A chronicle perspective review. Nano Energy 31, 113–143 (2017).Ulvestad, A. et al. Stoichiometry-Controlled Reversible Lithiation Capacity in Nanostructured Silicon Nitrides Enabled by in Situ Conversion Reaction. ACS Nano 15, 16777–16787 (2021).Kilian, S. O. et al. Active Buffer Matrix in Nanoparticle-Based Silicon-Rich Silicon Nitride Anodes Enables High Stability and Fast Charging of Lithium-Ion Batteries. Advanced Materials Interfaces 9, 2201389 (2022). Figure 1

Pre-Lithiation of Silicon-Based Anode Materials: Concepts and Realization

The capacity in lithium ion battery (LIB) relies on active lithium, i.e., lithium-ions and electrons, which separately shuttle between the electrodes during charge and discharge. Given state-of-the art active materials for anodes, loss of active lithium and capacity remains a major challenge during LIB operation, in particular in the first charge/discharge cycle due to electrolyte decomposition and formation of solid electrolyte interphase (SEI).Pre-lithiation, i.e., artificial increase in active lithium amount into the battery is a promising strategy to counteract active lithium loss. Electrochemical(1) and chemical(2,3) methods of pre-lithiation can be distinguished. While electrochemical methods are based on the use of an external power source, the driving force of the chemical reaction is a negative change in the Gibb´s free energy which in the case of pre-lithiation is provided by the use of highly reactive chemical compounds (e.g. lithium-organic complex solutions or lithium metal). The use of lithium metal allows for a wide range of technological processes, including lamination of lithium foil, gas-phase deposition, application of lithium melts or suspensions containing lithium powder. In this contribution, various concepts of pre-lithiation will be discussed from experimental and up-scaling point of view on the example of Si-based anodes.(1) Haneke, L.; Pfeiffer, F.; Bärmann, P.; Wrogemann, J.; Peschel, C.; Neumann, J.; Kux, F.; Nowak, S.; Winter, M.; Placke, T., Insights into Electrolytic Pre‐Lithiation: A Thorough Analysis Using Silicon Thin Film Anodes. Small 2022, 2206092.(2) Adhitama, E.; Bela, M. M.; Demelash, F.; Stan, M. C.; Winter, M.; Gomez‐Martin, A.; Placke, T., On the Practical Applicability of the Li Metal‐Based Thermal Evaporation Prelithiation Technique on Si Anodes for Lithium Ion Batteries. Advanced Energy Materials 2023, 13 (3), 2203256.(3) Bärmann, P.; Mohrhardt, M.; Frerichs, J. E.; Helling, M.; Kolesnikov, A.; Klabunde, S.; Nowak, S.; Hansen, M. R.; Winter, M.; Placke, T., Mechanistic Insights into the Pre‐Lithiation of Silicon/Graphite Negative Electrodes in “Dry State” and After Electrolyte Addition Using Passivated Lithium Metal Powder. Advanced Energy Materials 2021, 11 (25), 2100925.

Investigating the Impact of Si/C Supraparticles Size Distribution on the Lifetime of Li-Ion Battery Half-Cells

The development of high-performance anodes for lithium-ion batteries (LiBs) with robust cycling stability has become a prominent area of research. In our recent study (Amin et al. 2023), we demonstrated that adopting a hierarchical structuring strategy via spray drying can significantly improve the cycle life of silicon-based anode materials in contrast to their nanoparticle building blocks (4 wt.% of compounding carbon). This method enhances the structural stability of the anode, thereby improving cyclic performance and paving the way for the development of high-capacity LIBs.However, beyond phenomenological proof of principles, understanding the effect of supraparticles size distribution on electrochemical performance is of great significance for making Si-based active materials ready for the LiBs industry. Therefore, we systematically investigated the correlations between supraparticle median sizes/size distributions and other supraparticle properties such as their BET surface area, slurry rheology, coated layer quality, and the electrochemical Coulombic efficiency of half-cells. These findings revealed that supraparticles with large median sizes are stable against processing as compared to small size supraparticles as can be seen from atomic force microscopic (AFM) images of coated layers in Fig 1a. It is also discovered that large supraparticles enhance the 3rd cycle Coulombic efficiency (2 formation cycles) of Li-ion half cells at 0.5 C as shown in Fig.1b. However, there exists an optimal median size/size distribution above which the Coulombic efficiency and cycling stability of the supraparticles in half-cells starts to decrease.In short, supraparticles exhibit properties (e.g., high layer stability, low surface reactions) that outperform those of individual nanoparticles. Understanding the role of supraparticle sizes in generating anodes with a hierarchical structure demonstrates great promises towards tailored materials for enhanced LiB performance. This enables us to further unravel process-structure-property relationships and understand the physics behind the improved electrochemical performance of supraparticles. Publication bibliography Amin, Adil; Loewenich, Moritz; Kilian, Stefan O.; Wassmer, Theresa; Bade, Stefan; Lyubina, Julia et al. (2023): One-Step Non-Reactive Spray Drying Approach to Produce Silicon/Carbon Composite-Based Hierarchically Structured Supraparticles for Lithium-Ion Battery Anodes. In J. Electrochem. Soc. DOI: 10.1149/1945-7111/acb66b. Figure 1

Dual immobilization of porous Si by graphene supported anatase TiO2/carbon for high-performance and safe lithium storage

Smart surface coatings have been proven to be an effective strategy to significantly enhance the electronic conductivity and cycling stability of silicon-based anode materials. However, the single/conventional coatings face critical challenges, including low initial Coulomb efficiency (ICE), poor cyclability, and kinetics failure, etc. Hence, we proposed a dual immobilization strategy to synthesize graphene supported anatase TiO2/carbon-coated porous silicon composite (denoted as PSi@TiO2@C/Graphene) using industrial-grade ferrosilicon as lithium storage raw materials through the simple etching, combined with sol–gel and hydrothermal coating processes. In this work, the dual immobilization from the “confinement effect” of the inner TiO2 shell and the “synergistic effect” of the outer carbon shell, improves the kinetics of the electrochemical reaction and ensures the integrity of the electrode material structure during lithiation. Furthermore, the introduction of the graphene substrate offers ample space for dispersing and anchoring the Si-based granules, which in turn provides a stable 3D conductive network between the particles. As a result, the PSi@TiO2@C/Graphene electrode delivers high reversible capacity of 1605.4 mAh g−1 with 93.65% retention at 0.5 A g−1 after 100 cycles (vs. 4th discharge), high initial Coulomb efficiency (82.30%), and superior cyclability of 1159.9 mAh g−1 after 250 cycles. The above results suggest that the particle structure has great potential for applications in Si-based anode and may provide some inspiration for the design of other energy storage materials.

Bi-Continuous Si/C Anode Materials Derived from Silica Aerogels for Lithium-Ion Batteries

Poor cycling performance caused by massive volume expansion of silicon (Si) has always hindered the widespread application of silicon-based anode materials. Herein, bi-continuous silicon/carbon (Si/C) anode materials are prepared via magnesiothermic reduction of silica aerogels followed by pitch impregnation and carbonization. To fabricate the expected bi-continuous structure, mesoporous silica aerogel is selected as the raw material for magnesiothermic reduction. It is successfully reduced to mesoporous Si under the protection of NaCl. The as-obtained mesoporous Si is then injected with molten pitch via vacuuming, and the pitch is subsequently converted into carbon at a high temperature. The innovative point of this strategy is the construction of a bi-continuous structure, which features both Si and carbon with a cross-linked structure, which provides an area to accommodate the colossal volume change of Si. The pitch-derived carbon facilitates fast lithium ion transfer, thereby increasing the conductivity of the Si/C anode. It can also diminish direct contact between Si and the electrolyte, minimizing side reactions between them. The obtained bi-continuous Si/C anodes exhibit excellent electrochemical performance with a high initial discharge capacity of 1481.7 mAh g−1 at a current density of 300 mA g−1 and retaining as 813.5 mAh g−1 after 200 cycles and an improved initial Coulombic efficiency of 82%. The as-prepared bi-continuous Si/C anode may have great potential applications in high-performance lithium-ion batteries.

Ongoing advancement in examining si-based anode materials for lithium ion batteries

There is a developing interest in Lithium-ion batteries (LIBs) with more prominent energy thickness, and further developed cycling soundness has become progressively critical because of the rising fame of electric vehicles and convenient gadgets; efficient energy storage and utilization are vital for meeting these demands. Silicon-based materials offer a promising solution with a high hypothetical explicit limit, low lithium inclusion potential, predominance, and eco-agreeableness. Silicon has emerged as a formidable contender in advanced energy storage technology. Silicon-based materials are perceived as a highly promising option for the anode material in the up-and-coming age of LIBs. Despite the potential benefits of silicon-based anode materials, some limitations currently restrict their commercial use. Its significant volume changes during Li insertion/extraction resulting poor cycling performance and rapid electrochemical decay. This article summarizes current research on this issue. It analyzes silicon anode materials from two perspectives: different dimensional silicon nanostructures (zero-, one-, two-, and three-dimensional) and silicon-based composite materials. Like Carbon/Silicon composite materials. This article provides a comprehensive understanding of silicon anode materials' research status and a vital reference for optimizing their cycling abilities and improving their commercial value and serviceable range.

ZIFs derived multilayer carbon and CNT skeleton networks and graphene to encapsulate silicon nanoparticles for efficient lithium storage

The severe volume expansion and low electron mobility of silicon-based anode materials during cycling limit their further practical applications, and the use of a multilayer carbon skeleton network and graphene to encapsulate silicon nanoparticles is an effective strategy to cope with the volume expansion of silicon-alloyed anodes and to improve their electron transport. In this work, a carbon skeleton derived from dual ZIF materials was designed and the controlled growth of carbon nanotubes was achieved by changing the capping order of the ZIF materials, which effectively slowed down the capacity degradation of the battery during the cycling process. At a current density of 1 A g−1, the specific capacity of Si@D-C-ZIF@CNTs@rGO was maintained at 1498.3 mAh g−1 after 500 cycles, and the capacity was maintained at 96 % after 200 cycles of assembling Si@D-C-ZIF@CNTs@rGO as the anode into a full cell. The design of silicon-based anode materials with multi‑carbon skeletons is given a fresh concept by this work.