Performance Of Li-ion Batteries Research Articles

Enhancing the Performance and Stability of Li-Ion Batteries with Fluorinated Electrolytes: Insights from MD Simulation and Experimental Analysis

The significance of using fluorinated electrolytes, particularly fluorinated ethylene carbonate (FEC) and difluoro ethylene carbonate (DFEC), in the electrolyte system of 1.2 M LiPF6 in dimethyl carbonate (DMC)/fluorinated solvent (FEC/DFEC), was explored using classical molecular dynamic (MD) simulation and density functional theory (DFT) calculation in this work. Various parameters, such as radial distribution function (RDF), integral over RDF, transference number, coordination number, and solvation energy, were analyzed. The study demonstrated that DFEC enhances the reduction in binding energy of the solvation sheath compared to FEC. Additionally, the electrochemical performance of a practical full-cell 18650 of LiNi0.88Co0.10Al0.02O4 (NCA) cathode and graphite anode batteries was examined, confirming that 1.2 M LiPF6 in DMC/FEC/DFEC (4:0.5:0.5 %v) demonstrated the highest capacity retention after 1,000 cycles, surpassing 1.2M LiPF6 in DMC/fluorinated (4:1 %v, FEC and DFEC, respectively) and the previous electrolyte 1.2 M LiPF6 in EC/EMC/DEC/FEC (1:1:1:1.3 %V). Spectroscopy techniques, including DEMS, NMR, and GC-MS, were utilized to investigate the electrolyte decomposition, revealing CO2 and H2 as the main gas products during decomposition. NMR results identified some species, such as HF, H2O, acetal, formaldehyde, and unknown products, while GC-MS confirmed that all the solvents in the electrolyte take part in the decomposition process. This study highlights the potential of fluorinated electrolytes in battery systems and provides insight into their decomposition mechanism, contributing to the development of more efficient and stable battery systems.

Influence of Cyclic Alkyl Carbonate Ring-Opening Processes on Electrode/Electrolyte Interphase Formation in Li-Ion Batteries

Cyclic alkyl carbonates, such as ethylene and vinylene carbonate (EC and VC), form solid electrolyte interphases (SEI) suppressing continuous solvent reduction at the graphite anode. There is a consensus that the choice of carbonate clearly affects SEI performance. VC has been observed to polymerize, forming poly(VC), but also to release major amounts of CO2,1,2 which are two seemingly contradictory processes. In this work, we present a detailed study of reaction pathways of EC and VC in typical Li-ion battery electrolytes. The rate of the decomposition reactions of these carbonates in presence of hydroxide is monitored using an injection cell coupled mass spectrometer at varying temperatures ranging from 30°C to 60°C. The activation energies from the Arrhenius relationship between the CO2 evolution rate and the cell temperature confirms that VC hydrolysis is autocatalytic rather than stoichiometric. Direct quantifications and comparisons of the solubilized reaction products will be done over varying times and temperatures with the help of in-situ nuclear magnetic resonance (NMR) and Raman spectroscopy that will help in clarifying the individual steps in the reaction process. The kinetic studies of EC and VC hydrolysis in model systems like this is an important step towards improving our understanding towards carbonates as there is always some trace amounts of hydroxides present in the cells. The complex interconversions and equilibria of these organic alkyl carbonates and oxides investigated herein, will add to the knowledge of interphase formation processes, and support the tailoring of electrolyte formulations in order to enhance performance of future Li-ion batteries.

In Situ Raman Spectroelectrochemical Investigation of Composite Si Nanoparticle-Based Anode for Li-Ion Batteries during (de)Lithiation Process

The key degradation processes in the composite anode for the Li-ion batteries (LIBs) prepared using Si nanoparticles (SiNPs) with two types of a conductive carbon-based matrix [carbon black (CB) and carbonized polypyrrole (CPPy)] were studied by in situ Raman spectroelectrochemistry (SEC). This combined technique provides non-destructive and real-time monitoring of the chemical and structural changes that occur during battery operation. These processes, such as the crystal lattice changes (expansion/contraction) and possible degradation/amorphization of silicon, the solid electrolyte interphase (SEI) layer formation on the electrode surface during the charge/discharge reactions, and the stability of the carbon-based matrix, significantly affect the performance of Si-based LIBs in many ways. Especially, the large silicon volume expansion (more than 300%) and associated stress cause mechanical instability resulting in rapid capacity fading. To overcome this challenge, various strategies have been proposed, including the use of CPPy as a conductive matrix to prevent large volumetric changes and also provide a pathway for electron transfer.This study investigates the initial degradation mechanisms such as the formation of the SEI layer, as well as possible structural changes caused by the volume expansion of SiNPs. The shift of the first-order Raman peak of Si at 521 cm-1 which is assigned to crystalline silicon is related to the stress evolution in nanoparticles caused by the (de)lithiation-induced stress (tensile-to-compressive transition) in SiNPs and the native oxide on their surface. Additionally, the detailed in situ Raman measurement of the first lithiation cycle allowed us to detect the decomposition of the electrolyte (LiPF6 in EC/DMC) close to the Si surface which is associated with SEI layer formation. A decrease in the intensity of the Raman vibrational modes (700–1050 cm−1) of EC/DMC corresponding to the decomposition of the electrolyte was observed at reduction potentials of 0.8 V and 0.3 V vs. Li/Li+ corresponding to the same potentials determined by cyclic voltammetry. The Si-based anode containing CPPy as active carbon showed better electrochemical properties (higher charge/discharge capacity and cycling stability) in Li-ion batteries than Si/CB despite the higher conductivity of the latter. The correlation between the chemical structure of the active carbon and the electrochemical properties of the resulting Si-based anodes will be discussed.Acknowledgment: This work was supported by the Czech National Foundation, Project No. 21–09830S.

Correlating Solid-Electrolyte Interface Composition to Charge Transfer Resistance for Improved Low-Temperature Performance of Lithium-Ion Batteries

The adverse impact of low temperatures on Li-ion batteries (LIBs) is a well known challenge. Currently, at subfreezing temperatures, the efficiency of conventional LIBs greatly decreases compared to their room temperature performance, which of course severely limits the performance of applications using LIBs in the colder regions on the planet. From a fundamental perspective, the causes of such performance decreases are yet to be fully understood, but are believed to be related to the ability of ions to move through the various phases (as well as move across phase interfaces) that exist in the battery.Several studies have been conducted to improve the low-temperature performance of LIBs, most of them focusing on using solvents with lower viscosity and higher dielectric constant to promote transport through the electrolyte at the lower temperatures so as to achieve lower bulk resistance (Rbulk) of the cell. However, our Electrochemical Impedance Spectroscopy (EIS) studies at low temperatures have indicated that it is the charge transfer resistance (Rct) that grows exponentially as we go to sub-zero Celsius temperatures and is responsible for the increase in the total resistance of the cell. EIS on 3-electrode cells have shown that the anode side (Gr) is predominantly responsible for the poor cell performance, necessitating our focus on the charge transfer process in the Gr-electrolyte interface. We observe that the Rct is not only related to the Li-solvation shell but also to the composition of the Solid Electrolyte Interface (SEI). By modifying the electrolyte, such as by changing the salt concentration, adding additives, and changing the solvent, significant changes in the interface and hence in the RSEI and Rct of the cell have been observed. By combining EIS with various techniques like mass spectrometry, differential capacity analysis and SEM, we have been able to better understand the SEI composition and its impact on interfacial resistances. We specifically focus on the influence of SEI composition on the charge-transfer resistance of the cell, correlating the effect of amounts of LiF and carbonates in the SEI with the interfacial performance of the cell. Through these relations, we aim to facilitate the development of electrolytes by having a better understanding of the solvation shells and the SEI composition for low temperature performance.

Unexplored Reaction Pathways of Ethylene Carbonate during Solid Electrolyte Interphase Formation

The solid electrolyte interphase (SEI) keeps eluding our grasp. Fundamental understanding of Li-ion battery performance will not be complete until the major underlying reaction pathways of SEI formation and growth have been described.1 Although the SEI has been observed to be a complex and highly diverse matrix of in-/organic crystalline and amorphous aggregates, likely only few compounds are functional, i.e. passivate the electrode while at the same time sustaining the Li+ transport. The aim of the presentation is to provide experimental evidence for hitherto largely unexplored reaction pathways of several commonly observed SEI compounds (such as lithium ethyl dicarbonate, abbr. LEDC) and prove how the formation of the same can be altered by the choice of electrolyte additives. For instance, Electrochemical Quartz Crystal Microbalance with Dissipation monitoring complemented by Online Electrochemical Mass Spectrometry is demonstrated to separate electrochemical from chemical reactions in a multistep SEI formation process.2-3 Based on our experimental findings, the role and implication of each compound (be it LiOH, Li2O, LEDC, etc.) in the SEI formation process will be discussed.4

Construction of Co1-xS Nanoparticles Embedding in N-Doped Amorphous Carbon@Graphene with Enhanced Li-Ion Storage.

Cobalt sulfide is deemed a promising anode material, owing to its high theoretical capacity (630mAhg-1). Due to its low conductivity, fast energy decay, and the huge volume change during the lithiation process limits its practical application. In this work, a simple and large-scale method are developed to prepare Co1-xS nanoparticles embedding in N-doped carbon/graphene (CSCG). At a current density of 0.2C, the reversible discharge capacity of CSCG maintains 937mAhg-1 after 200 cycles. The discharge capacity of CSCG maintains at 596mAhg-1 after 500 cycles at the high current density of 2.0C. The excellent performance of CSCG is due to its unique structural features. The addition of rGO buffered volume changes while preventing Co1-xS from crushing/aggregating during the cycle, resulting in multiplier charge-discharge and long cycle life. The N-doped carbon provides a simple and easy way to achieve excellent performance in practical applications. Combined with density functional theory calculation, the presence of Co-vacancies(Co1-x) increases more active site. Moreover, N-doping carbon is beneficial to the improve adsorption energy. This work presents a simple and effective structural engineering strategy and also provides a new idea to improve the performance of Li-ion batteries.

A Brief Overview of Silicon Nanoparticles as Anode Material: A Transition from Lithium-Ion to Sodium-Ion Batteries.

The successful utilization of silicon nanoparticles (Si-NPs) to enhance the performance of Li-ion batteries (LIBs) has demonstrated their potential as high-capacity anode materials for next-generation LIBs. Additionally, the availability and relatively low cost of sodium resources have a significant influence on developing Na-ion batteries (SIBs). Despite the unique properties of Si-NPs as SIBs anode material, limited study has been conducted on their application in these batteries. However, the knowledge gained from using Si-NPs in LIBs can be applied to develop Si-based anodes in SIBs by employing similar strategies to overcome their drawbacks. In this review, a brief history of Si-NPs' usage in LIBs is provided and discuss the strategies employed to overcome the challenges, aiming to inspire and offer valuable insights to guide future research endeavors.

Internal Heating Techniques for Lithium-Ion Batteries at Cold Climates: An Overview for Automotive Applications

Lithium-ion (Li-ion) batteries suffer from substantial capacity and power degradation at low temperatures, severely deteriorating the performance of battery-based transportation electrification. To overcome this issue, different preheating techniques have been proposed to recover the performance of Li-ion batteries in cold climates. Among these, internal heating schemes are more promising than traditional conductive and convective approaches owing to their superiorities in terms of high efficiency, rapid speed, and uniform temperature distribution. This paper reviews various internal heating methodologies developed in recent years for Li-ion batteries, including mutual pulse current heating, alternating current heating, compound heating, and all-climate-battery based heating. Specifically, the effects of low temperatures on Li-ion batteries are first outlined in terms of cell performance and electrochemical characteristics. Then, the heat generation mechanism during internal heating is briefly described, based on which the internal temperature monitoring methods are also investigated considering the temperature gradient. Next, a comprehensive literature survey on different internal heating schemes with their basic principles, benefits, and drawbacks is presented. Finally, future trends of internal heating methods to benefit automotive battery performance are discussed in terms of key technologies, promising opportunities, and challenges.

The enhanced performance of Li-ion batteries based on Co-MOF/MXene composites

Electrospinning is carried out to fabricate Ti3C2Tx@Co nanocomposite films composed of 2D Ti3C2-encapsulated Co nanoparticles derived from Co-MOF precursors. The unique 1D nanochain structure inherits not only the high electrochemical activity, but also excellent electron and ionic conductivity. The Co nanoparticles with good conductivity and MXene with high electrochemical activity improve the electrochemical properties giving rise to high capacity and good cycling stability. The Ti3C2 flakes partially accommodate the volume changes during Li+ insertion/extraction and the electrospinning technique prevents self-aggregation of Ti3C2 flakes and aggregation of ZIF-67 nanoparticles, consequently producing a larger surface area and more active sites on the flexible anode. As a result, the MXene/Co composite has excellent properties such as a high reversible capacity of 422 mA h g−1 after 500 charging-discharging cycles at a current density of 1 A/g and retained capacity of 177 mA h g−1 at a rate of 5 A/g. The materials and strategy have large potential in commercial energy storage devices.

Tuning the Particle Size Distribution at Cathode for Enhanced Li-Ion Battery Performance

Tuning the Particle Size Distribution at Cathode for Enhanced Li-Ion Battery Performance

Enhancing electrochemical performance of solid-state Li-ion batteries with composite electrolytes of fibrous LLZTO and PVDF-HFP: The role of LLZTO fiber diameter

Composite solid electrolytes (CSEs) are synthesized using poly(vinylidene fluoride-co-hexafluoropropylene) incorporated in a three-dimensional framework of Li6.75La3Zr1.75Ta0.25O12 (LLZTO) ceramic fibers with varying diameters (80 nm, 140 nm, 290 nm, and 6 μm). The influence of LLZTO fiber diameter on the electrochemical performance of the CSEs is investigated. LLZTO fibers of smaller diameter improve the mechanical strength and electrochemical properties of the CSEs, including conductivity, activation energy, and transference number of lithium ion (Li+). Lithium iron phosphate batteries based on different CSEs are evaluated in terms of Li+ polarization, charge-discharge capacity, cycle life, and rate capability. The battery utilizing CSE with 6 μm LLZTO fibers displays an initial discharge capacity of 147 mAh g−1 at 0.2C but has a short charge-discharge life of only 47 cycles, with poor capacity retentions of 64 % and 17 % at 0.5C and 1.0C, respectively. In contrast, the battery with CSE containing 80 nm LLZTO fibers exhibits excellent cycle stability and satisfactory rate capability, maintaining an initial capacity of 161 mAh g−1 at 0.2C for over 200 cycles, with capacity retentions of 95 % and 78 % at 0.5C and 1.0C, respectively. Finite element simulations are employed to elucidate the intricate Li+ flux and trajectory within the ceramic and polymer regions of the composite electrolytes. Such details are beyond the reach of experimental methods alone, thereby enabling us to unravel the mechanism underlying the enhanced electrochemical properties of Li+ in CSEs with thinner LLZTO fibers.

Application of Nanomaterials in the Negative Electrode of Lithium-Ion Batteries

Li-ion batteries (LIBs) widely power modern electronics. However, there are certain limitations in the energy density, cycle life, and safety of traditional lithium-ion batteries, which restrict their further application and development. Therefore, new methods and technologies need to be explored to improve the performance stability of LIB. The emergence of nanomaterials provides new ideas and methods for the improvement of lithium-ion batteries. Nanomaterials have special structures and properties, and can improve the performance of LIB by regulating their morphology, size, and surface chemical properties. An overview of the development in research on using nanomaterials in LIB is given in this article. First, the features and benefits of nanomaterials were described, as well as the basic principles and development history of lithium-ion batteries. The use and performance of nanomaterials in lithium-ion batteries were then elaborated from a variety of angles, including nanosilicon, nanocarbon, and nanoiron oxide. Finally, the future applications of nanomaterials in lithium-ion batteries were prospected, and their development trends and challenges were pointed out. This article aims to provide a reference for the application of nanomaterials in lithium-ion batteries and promote further development in this field.

Insights into the kinetics–morphology relationship of 1-, 2-, and 3D TiNb2O7 anodes for Li-ion storage

Understanding the influence of electrode material’s morphology on electrochemical behavior is of great significance for the development of rechargeable batteries, however, such studies are often limited by the inability to precisely control the morphology of electrode materials. Herein, nanostructured titanium niobium oxides (TiNb2O7) with three different morphologies (one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D)) were synthesized via a facile microwave-assisted solvothermal method. The influence of the morphological dimension of TiNb2O7 as electrode material on the electrochemical performance in Li-ion batteries (LIBs) and the underlying correlation with the electrochemical kinetics were studied in detail. 2D TiNb2O7 (TNO-2D) shows a superior rate capability and cycling stability, associated with improved kinetics for charge transfer and Li-ion diffusion, compared to the 1D and 3D materials. Operando X-ray diffraction measurements reveal the structural stability and crystallographic evolution of TNO-2D upon lithiation and delithiation and correlate the Li-ion diffusion kinetics with the lattice evolution during battery charge and discharge. Moreover, carbon-coated TNO-2D achieves enhanced rate capability (205 mAh·g−1 at 50 C) and long-term cycling stability (87% after 1000 cycles at 5 C). This work provides insights into the rational morphology design of electrode materials for accelerated charge transfer and enhanced fast-charging capability, pushing forward the development of electrode materials for high-power rechargeable batteries in future energy storage.

Flexible phase change materials for low temperature thermal management in lithium-ion batteries

The performance of Li-ion batteries can degrade dramatically at cold ambient temperatures. The excess heat generated during battery operation can be stored by PCMs and then released at low ambient temperatures to insulate the battery. However, PCMs inevitably suffer from easy leakage and poor adaptability. In this study, we prepared a novel Oct/SEBS composite PCM and applied it in a low-temperature Li-ion battery thermal management system. The prepared Oct/SEBS has good shape stability, a sufficiently high latent heat (187.7 J/g), and thermally induced flexibility properties. In addition, the BTMS containing CPCM can exhibit excellent thermal insulation performance, which can insulate the Li-ion battery for more than 30 min even at −20 °C and increase the discharge capacity from 3.78 Ah to 5.49 Ah, which is very beneficial for the operation of the Li-ion battery at low temperatures.

Accurate Quantum Chemical Reaction Energies for Lithium-Mediated Electrolyte Decomposition and Evaluation of Density Functional Approximations.

An important concern related to the performance of Li-ion batteries is the formation of a solid electrolyte interphase on the surface of the anode. This film is formed from the decomposition of electrolytes and can have important effects on the stability and performance. Here, we evaluate the decomposition pathway of ethylene carbonate and related organic electrolyte molecules using a series of density functional approximations and correlated wave function (WF) methods, including the coupled-cluster theory with single, double, and perturbative triple excitations [CCSD(T)] and auxiliary-field quantum Monte Carlo (AFQMC). We find that the transition state barrier associated with ring opening varies widely across different functionals, ranging from 3.01 to 17.15 kcal/mol, which can be compared to the value of 12.84 kcal/mol predicted by CCSD(T). This large variation underscores the importance of benchmarking against accurate WF methods. A performance comparison of all of the density functionals used in this study reveals that the M06-2X-D3 (a meta-hybrid GGA), CAM-B3LYP-D3 (a range-separated hybrid), and B2GP-PLYP-D3 (a double hybrid) perform the best, with average errors of about 1.50-1.60 kcal/mol compared to CCSD(T). We also compared the performance of the WF methods that are more scalable than CCSD(T), finding that DLPNO-CCSD(T) and phaseless AFQMC with a DFT trial wave function exhibit average errors of 1.38 and 1.74 kcal/mol, respectively.

State-space modeling for electrochemical performance of Li-ion batteries with physics-informed deep operator networks

Online estimation of unobservable internal states is significant for safe operation of Li-ion batteries, and it constitutes one of the main functions of battery management system (BMS). The next-generation BMS expects model-based state estimation, especially with electrochemical models, which are accurate but often costly for solving. Therefore, it is required to build more easily executable state-space representation of electrochemical models for online state estimation. However, the traditional numerical methods for time discretization are relatively complicated, and the discretized system is not very flexible in modifying predictive time intervals. To address such issues, we introduce the concept of physics-informed operator learning for state-space modeling. Specifically, we propose an architecture, termed the physics-informed multiple-input operator network (PI-MIONet), to reformulate the state-space representation of the extended single particle (eSP) model. In this work, the PI-MIONet takes the Li-ion concentration of the whole electrode particle and current densities at the current time as the input functions, and predicts Li-ion concentration at any spatial-temporal location, which means that the forward predictions can be realized with user-defined step size. In addition, due to the capability of taking discretized functions as inputs, the PI-MIONet can be used for estimating states in the form of long vectors, and it can be conducted very efficiently, which makes it highly suitable for online applications in BMS. We verify the predictive performance of PI-MIONet through several synthetic experiments, and successfully apply it to the estimation of Li-ion concentration across the full particle with unscented Kalman filter algorithms.

Core–shell-structured Li[(Ni)0.5(Ni0.7Co0.3)0.5]O2 cathode material with high capacity and rate performance for high-energy Li-ion batteries

Core–shell-structured Li[(Ni)0.5(Ni0.7Co0.3)0.5]O2 cathode material with high capacity and rate performance for high-energy Li-ion batteries

Thermal Characteristics and Safety Aspects of Lithium-Ion Batteries: An In-Depth Review

This paper provides an overview of the significance of precise thermal analysis in the context of lithium-ion battery systems. It underscores the requirement for additional research to create efficient methodologies for modeling and controlling thermal properties, with the ultimate goal of enhancing both the safety and performance of Li-ion batteries. The interaction between temperature regulation and lithium-ion batteries is pivotal due to the intrinsic heat generation within these energy storage systems. A profound understanding of the thermal behaviors exhibited by lithium-ion batteries, along with the implementation of advanced temperature control strategies for battery packs, remains a critical pursuit. Utilizing tailored models to dissect the thermal dynamics of lithium-ion batteries significantly enhances our comprehension of their thermal management across a wide range of operational scenarios. This comprehensive review systematically explores diverse research endeavors that employ simulations and models to unravel intricate thermal characteristics, behavioral nuances, and potential runaway incidents associated with lithium-ion batteries. The primary objective of this review is to underscore the effectiveness of employed characterization methodologies and emphasize the pivotal roles that key parameters—specifically, current rate and temperature—play in shaping thermal dynamics. Notably, the enhancement of thermal design systems is often more feasible than direct alterations to the lithium-ion battery designs themselves. As a result, this thermal review primarily focuses on the realm of thermal systems. The synthesized insights offer a panoramic overview of research findings, with a deeper understanding requiring consultation of specific published studies and their corresponding modeling endeavors.

Protective behavior of phosphonate-functionalized imidazolium ionic liquid and its impact on the Li-ion battery performance

The commercial lithium-ion batteries (LIBs) rely on lithium hexafluorophosphate (LiPF6), which is extremely sensitive to moisture and liable to thermal decomposition. Lithium bis (trifluoro methane sulfonyl) imide (LiTFSI), as a promising electrolyte salt, possesses high thermal stability and excellent moisture tolerance. However, LiTFSI is closely related to severe corrosion of the aluminum (Al) current collector at high voltage. Herein, phosphonate-functionalized imidazolium ionic liquid (PFIL) is developed and utilized as an electrolyte co-solvent to inhibit the oxidative dissolution of the Al current collector. PFIL can suppress Al corrosion by participating in the interface reaction and forming a stable and reliable protective film on the surface of Al foils, as confirmed by X-ray photoelectron spectroscopy. Thanks to the corrosion suppression of the Al current collector, the Li||LiNi0.8Mn0.1Co0.1O2 (NCM811) cells with PFIL-containing electrolytes exhibit better cycling performance and improved capacity retention. This work proposes an effective strategy for the advancement of high-voltage LIBs and contributes to promoting the widespread use of the sulfone imide-based lithium salts.

SiO@Nb2O5@NC composite anodes with enhanced rate and cycle performance for Li-ion batteries

Although SiO/G (G denotes graphite) products are commercially available in nowadays, their scalable applications in Li-ion batteries are still limited by their poor stability and high cost. Herein, niobium oxide (Nb2O5) with open tunnel structure is composited with SiO in combination with N-doped carbon (NC) coating, which have jointly enhanced the rate and cycle performance of the resulting SiO@Nb2O5@NC composite anodes. Under optimum conditions, a capacity retention of 74% is preserved after 200 cycles at 0.2 A g−1, together with a high capacity of 666 mA h g−1 at 3 A g−1. Ex situ XRD analysis reveals that Nb2O5 is transformed to amorphous LixNb2O5 and electrochemical-inert NbO in the first lithiation process. The former exhibits fast Li+ migration rate and capacitive Li ion storage behavior, which may help to improve the electrochemical performance of SiO. Further mixing the SiO@Nb2O5@NC composite with spent graphite extracted from used LiFePO4 battery yields a high capacity and stable anode material that shows a high capacity retention of 79% after 500 cycles at 0.4 A g−1. This work may shed a light on the development of stable yet low cost SiO/G anode materials through pre-modification of SiO with Nb2O5 and utilization of cheap graphite resource.