Anode Material For Lithium-ion Batteries Research Articles

Electric-Thermal Analysis of Power Supply Module in Graphitization Furnace

Graphite, a key anode material in lithium-ion batteries, primarily relies on the Acheson graphitization furnace (AGF) for production. This research focuses on the power supply module of the AGF, particularly the electrodes and their power transmission clamps. A three-dimensional transient electric-thermal-fluid coupling model was developed to numerically analyze the temperature and electric field distributions during operation. The study revealed that heat conduction through furnace electrodes dominates temperature rise. Notably, clamping plates within transmission clamps exhibit high temperatures and gradients, posing a thermal failure risk. Efficient cooling plate design with liquid-cooled channels is crucial for temperature control. Additionally, maintaining high electrode temperatures reduces resistivity, lowering power consumption in the power supply module. This study provides insights into optimizing AGF power supply module design, emphasizing the importance of effective cooling strategies for clamping plates and the benefits of maintaining elevated electrode temperatures for energy efficiency.

Construction of 2D/1D rGO/H2Ti3O7 composite as anode for high performance lithium-ion batteries

Ultrafine one-dimensional (1D) H2Ti3O7 nanowires were prepared by a hydrothermal reaction with high concentration of KOH as base source. Then 2D/1D rGO/H2Ti3O7 architecture was constructed and investigated as the anode material for lithium-ion batteries. Benefiting from the addition of rGO nanosheets and the retention of ultrafine 1D H2Ti3O7 nanowires, the rGO/H2Ti3O7 electrode presented superior electrochemical performance with excellent rate capability, long cycling stability and high capacity in half cells. It delivered high reversible capacities of 274 mAh g−1 at 0.1 A g−1 and 163 mAh g−1 at 1 A g−1, as well as a long-term cycling performance (259.3 mAh g−1 at 0.2 A g−1 after 1000 cycles). The excellent electrochemical performance of the composite can be attributed to the unique architecture with smaller diameter of 1D H2Ti3O7 nanowires and conductive rGO nanosheets to shorten the transmission distance of electrons and Li+ and improve the electrical conductivity in rGO/H2Ti3O7 composite.

Preparation and electrochemical properties of nitrogen-doped starch hard carbon anode materials for lithium-ion battery

Here, we report the synthesis of hard carbon materials (CSHs) made from corn starch and their application as an anode in lithium-ion batteries. The study shows that the microstructure and electrochemical properties of CSHs are affected by nitrogen doping. It is found that nitrogen is embedded in the carbon layer with graphite nitrogen, pyridyl nitrogen, and pyrrole nitrogen, so that the surface morphology was changed and reduced the disorder of the materials. The electrochemical test results show that the introduction of nitrogen elements can increase the reversible capacity of the material, with the first discharge capacity reaching above 426.35 mAh g−1, and the rate performance also improves. When melamine and pre-carbonized corn starch are carbonized at a mass ratio of 1:9, the obtained material has a reversible capacity of 122.04 mAh g−1 at a rate of 2 C. During the carbonization process, the nitrogen in melamine is doped into the carbon materials, improving the electrochemical performance of the material.

Magnesiothermic reduction SiO coated with vertical carbon layer as high-performance anode for lithium-ion batteries

Silicon monoxide (SiO), as one of the most competitive anode materials for lithium-ion batteries (LIBs), has received considerable attention. Nevertheless, poor initial Coulombic efficiency (ICE) and larger volume change are the main obstacles to the application of SiO. Here, we suggest a controllable route for the modification of micro-sized SiO via magnesiothermic reduction. To prevent the excessive growth of Si grains caused by the overheating reaction, the solid-state thermal reaction between Mg and SiO is achieved by mixing a certain proportion of NaCl at a suitable temperature, resulting in a loose surface and porous structure of SiO particles, which is conducive to the transportation of lithium ions and electrons. Combined with chemical vapor deposition (CVD), the carbon-coated SiOx composites (M-SiOx@C-R, where R is the molar ratio for Mg and SiO) exhibit unique morphology structure and remarkable electrochemical characteristics. As expected, the vertical carbon network improves the conductivity and alleviates the volume expansion of SiOx. Notably, the M-SiOx@C-0.75 electrode offers a large initial specific capacity of 2283.17 mAh g−1 with a higher ICE of 86.03 % at 100 mA g−1. Furthermore, the full cells using M-SiOx@C-0.75 composite as the negative electrode and LiNi0.8Co0.1Mn0.1O2 (NCM811) as the positive electrode were assembled. After 150 cycles, the full cell still delivers a high specific capacity of 72.22 mAh g−1 (with a retention rate of 47 %). This work provides a feasible route for the fabrication of applicable SiO-based anode materials.

Solid-State Construction of CuO-Cu2O@C with Synergistic Effects of Pseudocapacity and Carbon Coating for Enhanced Electrochemical Lithium Storage.

The pseudocapacitive effect can improve the electrochemical lithium storage capacity at high-rate current density. However, the cycle stability is still unsatisfactory. To overcome this issue, a multivalent oxide with a carbon coating represents a plausible technique. In this work, a CuO-Cu2O@C composite has been constructed by a one-step bilayer salt-baking process and utilized as anode material for lithium-ion batteries. At a current density of 2.0 A g-1, the as-prepared composite delivered a stable discharge capacity of 431.8 mA h g-1 even after 600 cycles. The synergistic effects of the multivalence, the pseudocapacitive contribution from copper, and the carbon coating contribute to the enhanced electrochemical lithium storage performance. Specifically, the existence of cuprous suboxide improves the electrochemical conductivity, the pseudocapacitive effect enhances the lithium storage capacity, and the presence of carbon ensures cycle stability. The testing results show that CuO-Cu2O@C composite has broad application prospects in portable energy storage devices. The present work provides an instructive precedent for the preparation of transition metal oxides with controllable electronic states and excellent electrochemical performance.

In-situ assembly of 3D VS2/Reduced graphene oxide with superior lithium ion storage performance: The role of heterojunction

VS2 is a potential anode material for lithium-ion batteries (LIBs) due to its advantageous properties. Herein, a novel three-dimensional (3D) VS2/reduced graphene oxide (rGO) heterostructure (VS2-rGO) was fabricated by in-situ assembly of caterpillar-like VS2 nanosheets on rGO. This 3D VS2-rGO with a well-defined heterojunction interface is engineered to mitigate the volumetric expansion of VS2 during Li + intercalation/deintercalation cycles. This optimized design promotes enhanced conductivity across the heterojunction, facilitating efficient electron and ion transport. The VS2-rGO electrode shows higher reversible capacity and better rate performance (644.02 mA h g−1 at 0.1 A g−1 after 140 cycles, 526.66 mA h g−1 at 2 A g−1) as compared to the pure VS2 electrode (433.69 mA h g−1 at 0.1 A g−1 after 140 cycles, 63.91 mA h g−1 at 2 A g−1). Ex-situ XRD analysis suggests that the Li + storage mechanism in the VS2-rGO electrode involves the initial intercalation, followed by intercalation and conversion. The lower Li + diffusion barrier within the VS2-rGO heterojunction (0.183 eV) compared to the VS2 layers (0.225 eV), as predicted by first-principles calculations, resulting the enhanced Li + transport kinetics and improved cycling performance of the VS2-rGO electrode material. This work offers novel perspectives for the influence of heterojunctions on LIBs.

One step for the construction of MnCO3-Mn3O4 composite for the high-performance lithium-ion batteries

In this work, MnCO3-Mn3O4 composite materials were prepared by one-step solvothermal method. The structure, morphology and chemical composition were characterized and analyzed. As the anode materials of lithium-ion batteries, the formed MnCO3-Mn3O4 composites on the basis of initial KMnO4/DMF weight ratio of 1:40 and 1:20 delivered the specific discharge capacities of 654.8 and 598.7 mA h g−1 after 100 cycles at a current density of 1.0 A g−1. The testing results indicate that MnCO3-Mn3O4 composite has significant advantage in electrochemical lithium storage capacity and can be utilized as one prospective anode material for the high performance lithium-ion batteries.

Self-assembled Si-based anode combined with electrostatic spinning method to realize high-performance lithium-ion batteries

Addressing the volume expansion when silicon and metal oxides alone are used as anode materials for lithium-ion batteries. This study used a simple self-assembly method and electrostatic spinning technique to prepare silicon@copper oxide@carbon nanofibres (CNFs) anodes with dual modification. The high rigidity of metal oxide CuO and the excellent cycling stability of CNFs effectively reduce the buildup of silicon particles, alleviate the volume expansion effect, and improve the electrical conductivity, which leads to better cycling stability and larger specific capacity of lithium-ion batteries. An excellent reversible specific capacity of 748.5 mAh g‐1−1 was observed after 800 cycles at a high current density of 1 A g−1. In addition, the surface of Si@CuO@CNFs electrodes remains smooth and undamaged after 800 cycles, and the increase in cross-sectional thickness is about 68 %, which is significantly smaller than the 300 % increase in cross-sectional thickness of pure Si anode and effectively improves the specific capacity of Li-ion batteries. This research optimizes the design of silicon-based anode materials with simple and mature process technology, which makes an indispensable contribution to developing high-efficiency, long-life, and environmentally friendly lithium-ion batteries. The easy availability and non-polluting nature of the materials used also effectively reduce the reliance on rare or expensive elements, minimize the production process's environmental impact, and vigorously promote the global energy transition and low-carbon green development strategy.

Hollow Ni/NiO@N-doped porous carbon for lithium ion battery anode based on dual-buffering strategy

As a promising anode material of lithium-ion batteries (LIBs), the poor electrical conductivity and severe volume expansion during cycling of nickel oxide (NiO) greatly limit its practical application. Here, a hollow nitrogen-doped porous carbon-loaded hollow Ni/NiO nanocomposite (Ni/NiO@HNC) was obtained by introducing Ni2+ into hollow covalent organic framework (HCOF) and then calcining the Ni2+/HCOF. The as-prepared Ni/NiO is nanoscale and hollow, which effectively accommodates the expanded volume of NiO. Hollow nitrogen-doped porous carbon (HNC) obtained from HCOF can further accommodate the expanded volume of NiO. The residual Ni and HNC can improve the electrical conductivity of Ni/NiO@HNC greatly. The regular pores of HNC inherited from HCOF facilitate the Li+ transfer. Thus, the Ni/NiO@HNC-2 composites exhibited outstanding cycle stability and rate performance when utilized as anode materials in LIBs. Even after 200 cycles at 0.1 A g−1, the capacity was still kept at 695.1 mAh g−1. The work provides an idea to prepare LIBs anodes based on dual-buffering strategy.

Formation of hollow stepped FePBA@rGO anode for high-performance lithium-ion batteries

Prussian blue and its analogues (PBAs) have been considered promising anode materials for lithium-ion batteries (LIBs) owing to their high theoretical capacity and cost-effectiveness. However, they often encounter challenges such as poor electronic conductivity and structural instability. Herein, we introduce a hollow stepped FePBA framework structure coated with reduced graphene oxide (FePBA@rGO). This sophisticated design significantly improves electronic conductivity and optimizes the diffusion pathways for lithium ions, leading to exceptional cycling stability and rate performance. The FePBA@rGO-15 anode developed in this study shows a notable rate capability of 294 mAh g−1 at a current density of 2 A g−1. More significantly, it demonstrates exceptional lithium storage performance, maintaining a capacity of 1245 mAh g−1 after 600 cycles at a current density of 1 A g−1. Density functional theory simulations further support our findings by illustrating that the robust interface between FePBA and rGO significantly accelerates the reactions kinetics of Li+ within the FePBA framework. This study represents a significant advancement towards improving the capacity and cycling stability of PBA-based anode materials, offering promising prospects for future battery applications.

Enhancing Rapid Li+/Na+ Storage Performance via Interface Engineering of Reduced Graphene Oxide-Wrapped Bimetallic Sulfide Nanocages.

Transition-metal sulfide is considered to be an admirable transformational electrode material due to low cost, large specific capacity, and good reversibility in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). Herein, the reduced graphene oxide-wrapped open bimetallic sulfide (NiS2-Co3S4@rGO) nanocage, derived from nickel-cobalt Prussian blue, was obtained by two-step calcination. There are luxuriant pore structures in the nanocage composite with a specific surface area of 85.28 m2 g-1, which provides plentiful paths for rapid transmission of Li+/Na+ and alleviates the volume stress caused by insertion and extraction of alkali metal ions. The excellent interface combination of bimetallic sulfide wrapped in reduced graphene oxide improves the conductivity and overall performance of the battery. Thanks to the special interface engineering, the open NiS2-Co3S4@rGO nanocage composite displays rapid lithium storage properties with an average diffusion coefficient of 8.5 × 10-13 cm2 s-1. Moreover, after 300 cycles, the reversible capacity of the composite is 1113.2 mAh g-1 at 1 A g-1. In SIBs, the capacity of the open NiS2-Co3S4@rGO composite is 487.9 mAh g-1 when the current density is 5 A g-1. These preeminent performances demonstrate the enormous development prospects of bimetallic sulfide nanocage as anode material in LIBs and SIBs.

Highly Graphitized Coal Tar Pitch-Derived Porous Carbon as High-Performance Lithium Storage Materials.

Because of its high specific capacity and superior rate performance, porous carbon is regarded as a potential anode material for lithium-ion batteries (LIBs). However, porous carbon materials with wide pore diameter distributions suffer from low structural stability and low electrical conductivity during the application process. During this study, the calcium carbonate nanoparticle template method is used to prepare coal tar pitch-derived porous carbon (CTP-X). The coal tar pitch-derived porous carbon has a well-developed macroporous-mesoporous-microporous hierarchical porous network structure, which provides abundant active sites for Li+ storage, significantly reduces polarization and charge transfer resistance, shortens the diffusion path and promotes the rapid transport of Li+. More specifically, the CTP-2 anode shows high charge capacity (496.9 mAh g-1 at 50 mA g-1), excellent rate performance (413.6 mAh g-1 even at 500 mA g-1), and high cycling stability (capacity retention rate of about 100 % after 1,000 cycles at 2 A g-1). The clean and eco-friendly large-scale utilization of coal tar pitch will facilitate the development of high-performance anodes in the field of LIBs.

Electrospun three dimensional TiO2@N/P co-doped carbon nanofibers framework as high-performance anode materials for lithium-ion batteries

Electrospinning combined with heating treatment is employed to fabricate N/P co-doped carbon nanofibers encapsulating homogenous ultrafine TiO2 nanoparticles (TiO2@N/P-CNFs). Characterization results reveal that one-dimensional electrospun composite nanofibers with high electronic conductivity and structural integrity are interconnected with each other to construct a three-dimensional conductive nanofiber network as efficient ion/electron transport channels. Specifically, the Li//TiO2@N/P-CNFs coin cell delivers an initial discharge specific capacity of 754.9 mAh/g at 100 mA/g and maintains the reversible specific capacity of 486.1 mAh/g after 100 cycles. Moreover, the cell expresses the exceptional rate capability with discharge specific capacity of 272.2 mAh/g at 2000 mA/g, whose capacity can be restored to 474.3 mAh/g as soon as the current density is returned to 100 mAh/g. Furthermore, Li//TiO2@N/P-CNFs cell demonstrates a significant pseudocapacitive contribution of 78% at 1.0 mV/s. The excellent electrochemical performance can be explained by the fact that the N/P co-doping strategy is promising strategy for facilitating Li+ ions storage and transfer by broadening interlayer distance and increasing the distribution of defects and active sites. Besides, ultrafine TiO2 nanoparticles with diameter of about 7 nm harness excellent mechanical strength to maintain structural stability upon cycling. Therefore, easily fabricated TiO2@N/P-CNFs composite nanofibers with excellent electrochemical properties may be served as a promising option for advanced anode materials for lithium-ion batteries.

Carbon Nanotubes Connecting and Encapsulating MoS2-Doped SnO2 Nanoparticles as an Excellent Lithium Storage Performance Anode Material.

Doping and carbon encapsulation modifications have been proven to be effective methods for enhancing the lithium storage performance of batteries. The hydrothermal method and ball milling are commonly used methods for material synthesis. In this study, a composite anode material rich in carbon nanotubes (CNTs) conductive tubular network connection and encapsulation of SnO2-MoS2@CNTs (SMC) was synthesized by combining these two methods. In this highly conductive network, nano-SnO2 particles are uniformly dispersed and embedded in MoS2 with a layered structure, and the obtained SnO2-MoS2 composite material is tightly connected and encapsulated by the tubular network of CNTs. It is worth noting that the incorporation of layered MoS2 not only effectively anchors the SnO2 nanoparticles, but also provides a broader space for lithium-ion movement due to the larger interlayer spacing. The conductive network of CNTs shortens the diffusion path of electrons and Li+ and provides more diffusion channels. The reversible capacity of the SnO2-MoS2@CNTs nanocomposite material remains at 1069.3 mA h g-1 after 320 cycles at 0.2 A g-1, and it exhibits excellent long-term cycling stability, maintaining 904.5 mA h g-1 after 1000 cycles at 1.0 A g-1. The composite material demonstrates excellent pseudocapacitive contribution rate performance, with a contribution rate of 87% at 2.0 mV s-1. The results indicate that SnO2-MoS2@CNTs has excellent electrochemical lithium storage performance and is a promising anode material for lithium-ion batteries.

Comparative insight into crystal evolutions of monodisperse MNb2O6 (M = Ni, Cu, Zn) spheres during electrochemical cycling in Li/Al-ion batteries

Niobates have emerged as advanced anode materials for lithium-ion batteries, owing to their inherently higher voltage and the occurrence of multiple one-electron redox reactions. However, there is a lack of comprehensive comparative analysis regarding their performance in lithium-ion and aluminum-ion battery applications. In this study, a facile solvothermal process is developed to synthesize uniform submicrospheres of three niobates: NiNb2O6, CuNb2O6, and ZnNb2O6 with large specific surface area and narrow size distribution. Their superior textural properties consisting of interconnected nanograins offer numerous active sites, delivering enhanced capacity and rate performance for the constructed half and full cells. Our in-situ XRD analysis reveals that all three niobates exhibit ultralow crystal volume expansion (< 6 %). But they exhibit distinct ion storage mechanisms: CuNb2O6 undergoes a phase transition to LiNb3O8 and NbO2 upon cyclic insertion of Li+ ions; NiNb2O6 mainly involves a classic hybrid-controlled process, facilitating easy ion insertion/extraction into/from the crystal lattices, especially at low sweep rates; while ZnNb2O6 stores charges via a pseudocapacitive-controlled process. Density functional theory (DFT) calculation and ex-situ XRD analysis confirm that CuNb2O6 outperforms the others, displaying the best electrochemical performance and holding promise as a high-energy electrode material thanks to favorable phase conversion, enhanced transport channels, porous structure and spherical morphology.

Novel design of Sn4P3@NxC electrodes and their electrochemical properties

Tin phosphide (SnxPy) is recognized as one of the most promising anode materials for lithium-ion batteries due to its exceptionally high theoretical capacity. However, its application is hampered by significant volume expansion during charge-discharge cycles and inferior electrical conductivity. Proper structural design plays a pivotal role in addressing these challenges, paving the way for high-performance anode materials. This study introduces a nitrogen-doped carbon-coated Sn4P3 nanosphere with a core-shell structure, employing dopamine as the nitrogen source. This innovative approach, utilizing template removal and solid-phase phosphorization, results in both the core and shell acting as active materials, thereby enhancing the volumetric energy density of the electrode. The internal voids within the shell layer mitigate volume expansion during charge-discharge cycles, while the presence of the nitrogen-doped carbon layer maintains the material's stability throughout cycling and improves its electrical conductivity. Electrochemical performance tests confirm this material's outstanding energy storage capability, with an initial Coulombic efficiency reaching up to 73.6 %. Furthermore, it maintains a stable capacity of 585 mAh g−1 after 1200 cycles at a current density of 2 A g−1. This research offers a design paradigm for developing novel energy storage materials.

MoS2/SnS heterostructure composite for high-performance lithium-ion battery anodes

Layered metal sulfides are potential anode materials for lithium-ion batteries (LIBs) because their unique structure makes them suitable for Li+ de-intercalation. As a typical 2D layered material, MoS2 is a potential anode material for LIBs due to the weak van der Waals forces between the layers, which facilitates the de-intercalation of Li+ and supports multiple Li+. However, when MoS2 is used as anodes for LIBs material, rapid capacity decay hinders the application. Coupling two different materials to form a heterogeneous structure is an effective way to solve the above problems. In this work, one-pot hydrothermal method is proposed to construct MoS2/SnS heterostructure composites. The electrochemical properties are significantly enhanced, which could be attributed to the presence of heterogeneous structures, leading to increase the electrode charge transfer rate and interfacial reaction kinetics. The results show that the discharge capacity of the MoS2/SnS-1.5 electrode is about 1492.1 mAh/g at 500 mA/g. Furthermore, assembled MoS2@SnS-1.5||LiCoO2 full cell displays a high discharge capacity of 226.1 mAh/g after 50 cycles at 500 mA/g. This facile method provides the application value of layered metal sulfides as LIBs anode materials.

Hierarchical mesoporous Co3O4@C-N nanostructure rods derived from a metal-organic framework as high-performance anode for lithium-ion battery

A uniform hierarchical mesoporous Co3O4@C-N nanostructure rods were in situ fabricated successfully by developing a facile one-step strategy. Cobalt-based metal organic framework [Co3(ndc)(HCOO)3(μ-OH)(H2O)]n with special Co chine constructed framework structure treated as a precursor directly pyrolyzed in a mixed atmosphere of argon and oxygen (95:5) at 500 °C for 2 h. According to the XRD pattern, SEM, TEM, EDS mapping images and XPS spectrum analysis, the well-defined hierarchical mesoporous Co3O4@C-N nanostructure rods showed pure Co3O4 phase, are assembled from a large number of core–shell structured Co3O4@C-N spherical particles with an ultrasmall and uniform size (∼8 nm) which were further connected by N doped carbon net to form nanostructure rods. Using as anode material for lithium-ion batteries, these hierarchical mesoporous Co3O4@C-N nanostructure rods exhibit excellent electrochemical performance with high reversible capacity, rate capability and good cycling stability. They maintained a reversible specific capacity of more than 1000 mAh/g at 100 mA/g, and the discharge specific capacities at the 5 current density of 0.1, 0.2, 0.5, 1, 2, and 5 A/g reached 1123, 1094, 1044, 979, 879 and 688 mAh/g, respectively.

A facile one-pot synthesis of ultrafine Sn/N-doped carbon/graphene oxide composite for superior lithium-ion storage

Metallic Sn is considered as a promising candidate of anode materials for lithium-ion batteries (LIBs) owing to its high capacity and ease of preparation. However, it undergoes severe mechanical damage after several lithiation/delithiation cycles due to the large volume change (∼300%). In this study, ultrafine Sn nanograins are embedded in N-doped amorphous carbon and then anchored onto reduced graphene oxide (rGO) via a facile one-pot synthesis route. The resulting composite consists of highly active Sn nanograins, three-dimensional carbon frameworks and highly conductive graphene oxide matrices. This unique configuration endows the composite with promising electrochemical performance. It delivers a reversible capacity of 1392 mAh g−1 at a current density of 50 mA g−1. When cycled after 300 times at 500 mA g−1, it still maintains a reversible capacity of 805 mAh g−1.

Hydrothermal synthesis of SnO2/MoO3-x/rGO ternary nanocomposites as a high-performance anode for lithium ion batteries

The theoretical specific capacity of tin dioxide (SnO2) as a lithium-ion batteries (LIBs) anode material is up to 1494 mAh·g−1, far exceeding that of graphite. However, the low conductivity, volume expansion, crushing failure and particles agglomeration during charge/discharge cycles limit its application in LIBs. In this work, the SnO2/MoO3-x/rGO composite material was synthesized by one-step hydrothermal method, with SnO2 and amorphous MoO3-x tightly and uniformly anchored at the surface of reduced graphene oxide (rGO). The results of structural characterization and electrochemical performance evaluation show that amorphous MoO3-x can increase the reactive active sites, inhibit Sn particles aggregation, and promote the reversible reaction of SnO2. rGO effectively improves the electrical conductivity of the composite and buffers the volume change of Li-Sn alloying/dealloying during cycles. In addition, due to introduction of MoO3-x and rGO a stable SEI film can be formed at the material's surface to improve the cycle stability. SnO2/MoO3-x/rGO exhibits excellent rate performance and cycle performance. When the rGO content is 10.9 wt%, the reversible capacity of the composite reach 813 mAh·g−1 after 800 cycles at current density of 1.0 A·g−1, and 450.6 mAh·g−1 after 1000 cycles at current density of 5.0 A·g−1, with the capacity retention rate of 96.9%.