Anode Material For Li-ion Batteries Research Articles

Investigation of N C and B C bilayers as anode materials for Li-ion batteries by first-principles calculations.

The best choice today for a realistic method of increasing the energy density of a metal-ion battery is to find novel, effective electrode materials. In this paper, we present a theoretical investigation of the properties of hitherto unreported two-dimensional B C and N C bilayer systems as potential anode materials for lithium-ion batteries. The simulation results show that N C bilayer is not suitable for anode material due to its thermal instability. On the other hand B C is stable, has good electrical conductivity, and is intrinsically metallic before and after lithium intercalation. The low diffusion barrier (0.27 eV) of Li atoms shows a good charge and discharge rate for B C bilayer. Moreover, the high theoretical specific capacity (579.57 mAh/g) connected with moderate volume expansion effect during charge/discharge processes indicates that B C is a promising anode material for Li-ion batteries.

β12-Borophene/Graphene Heterostructure as a High-Performance Anode Material for Li-Ion Batteries.

In the world of two-dimensional (2D) materials, various Borophene allotropes have gained significant attention for their remarkable specific capacity. However, the instability of monolayers has challenged experimental investigations of innovative approaches. Due to this limitation, in this work, graphene was investigated as a sublayer with the aim of providing stability to the β12-borophene monolayer. This study delves into the potential of a novel β12-borophene/graphene (β12-B/G) van der Waals (vdW) heterostructure using Quantum Espresso software based on vdW-corrected density functional theory. Our investigation includes exploring thermal and dynamical stability, adsorption energy, open circuit voltage, specific capacity, and diffusion barrier energy properties. Impressively, the calculated specific capacity reached 907 mAh/g, outperforming other 2D materials and heterostructures. The combination of a graphene layer not only ensures dynamical stability but also provides the adsorption energy of lithiumon the β12-borophene layer, simultaneously decreasing the diffusion barrier energy in comparison with the β12-borophene monolayer. The calculated open circuit voltage falls in the range 0.08-1.09 V, rendering it suitable for an overall average commercial voltage. For the borophene layer, the computed diffusion barrier energies are approximately 0.52 and 0.78 eV. Collectively, these findings underscore the potential of theβ12-B/G heterostructure as an advanced anode material for lithium-ion batteries.

In Situ Integration of a Flame Retardant Quasisolid Gel Polymer Electrolyte with a Si-Based Anode for High-Energy Li-Ion Batteries.

Silicon (Si) stands out as a promising high-capacity anode material for high-energy Li-ion batteries. However, a drastic volume change of Si during cycling leads to the electrode structure collapse and interfacial stability degradation. Herein, a multifunctional quasisolid gel polymer electrolyte (QSGPE) is designed, which is synthesized through the in situ polymerization of methylene bis(acrylamide) with silica-nanoresin composed of nanosilica and a trifunctional cross-linker in cells, leading to the creation of a "breathing" three-dimensional elastic Li-ion conducting framework that seamlessly integrates an electrode, a binder, and an electrolyte. The silicon particles within the anode are encapsulated by buffering the QSGPE after cross-linking polymerization, which synergistically interacts with the existing PAA binder to reinforce the electrode structure and stabilize the interface. In addition, the formation of the LiF- and Li3N-rich SEI layer further improves the interfacial property. The QSGPE demonstrates a wide electrochemical window until 5.5 V, good flame retardancy, high ionic conductivity (1.13 × 10-3 S cm-1), and a Li+ transference number of 0.649. The advanced QSGPE and cell design endow both nano- and submicrosized silicon (smSi) anodes with high initial Coulombic efficiencies over 88.0% and impressive cycling stability up to 600 cycles at 1 A g-1. Furthermore, the NCM811//Si cell achieves capacity retention of ca. 82% after 100 cycles at 0.5 A g-1. This work provides an effective strategy for extending the cycling life of the Si anode and constructing an integrated cell structure by in situ polymerization of the quasisolid gel polymer electrolyte.

Sulphonated coal tar pitch as a carbon source to develop the storage capacity of Fe2O3@C materials

Utilizing metal oxides as substitutes for carbon anodes is imperative in advancing LIBs. Recently, the researchers regarding to the Fe2O3 have become very popular owing to its advantages such as a high theoretical capacity (1007 mAh g-1), cost-effectiveness and sustainability. In our present studies, the Fe2O3@SCTPC (Fe2O3 nanosphere coated by carbons which are obtained by the carbonizations using the sulphonated coal tar pitches) materials are firstly and successfully fabricated by a one-step hydrothermal method using the Fe(NO3)3·9H2O and sulphonated coal tar pitches (SCTPs). An intriguing observation is that the nanosphere Fe2O3 is encapsulated by carbons with a core-shell structure. This specific core-shell structure effectively mitigates the volume expansion of Fe2O3, and exhibits a notable enhancement in conductivity. Thanks to this unique structure, the Fe2O3@SCTPC electrode has a maximum capacity of 1106.74 mAh g-1 after 100 cycles at a current density of 0.1Ag-1 and a high reversible specific capacity of 373.5 mAh g-1 after 500 cycles at a current density of 2Ag-1, when it is used as an anode material for Li-ion battery. These results suggest that adjusting the structures of carbons is crucial to develop the potential storage capacity of the covered Fe2O3.

Versatile multi-lithiophilic metal oxide nano seeds embedded in hollow carbon nanospheres via electrostatically functional template for dendrite-free lithium metal anodes

Lithium metal anodes, which are promising candidates for anode materials in Li-ion batteries, are highly regarded for their combination of high energy density and low electrochemical potential, making them a compelling option for next-generation anodes. However, the growth of dendritic Li during the charging and discharging processes, along with the resulting decrease in stability and efficiency, poses a significant obstacle to the commercialization of Li metal anodes. To address the challenges associated with Li metal anodes, we propose the use of hollow carbon incorporating zinc oxide (ZnO) and magnesium oxide (MgO) as anode materials. ZnO has high lithiophilicity, enabling selective reactions with Li ions, and MgO exhibits a low nucleation overpotential. By placing these two substances inside the hollow carbon structure, stable Li growth can occur within the hollow carbon, enabling the formation of a reliable Li metal anode. Furthermore, to simplify and precisely synthesize the proposed structure, polystyrene-b-polyacrylic acid was introduced. Metals such as Zn and Mg can be uniformly attached to the hollow carbon through the carboxylic group of acrylic acid. The synthesized structure exhibited significantly improved Li storage performance compared to that of hollow carbon. It demonstrated superior metrics, achieving a Coulombic efficiency of 99.8% over 350 cycles. The introduction of Zn and Mg with distinct properties effectively enhanced the internal storage performance of Li in hollow carbon.

Solid-state lithium batteries composed of hematite and oxide electrolyte

As Li-ion battery anode materials, two types of hematite (Fe2O3(big), Fe2O3(ultrafine)) were evaluated by using liquid electrolyte and oxide-based solid electrolyte. Although the anode using Fe2O3(ultrafine) with larger specific surface area showed a high initial reversible capacity in the liquid-electrolyte cell, there was a steep capacity decay in the cycling test. In the solid-electrolyte cell, we obtained very low reversible capacities of 40 mA h g−1 for the anode using Fe2O3(big) with smaller specific surface area. In contrast, the capacity of Fe2O3(ultrafine) anode was as high as 400 mA h g−1 at the 20th cycle. This is the first demonstration of charge–discharge reactions for Fe2O3 anode in oxide-based solid-state batteries. The Fe2O3(ultrafine) particles were dispersed relatively uniformly between solid electrolyte in the active layer, suggesting that the contact area between Fe2O3 and solid electrolyte becomes large. Consequently, Fe2O3(ultrafine) could benefit from larger contact area delivering the suitable reaction site for Li+ to improve the anode performance.

Low diffusion barrier in black phosphorene/graphdiyne heterostructure for ultrafast Li-ion battery anode

Black phosphorene (BlackP) with low diffusion barriers has been extensively researched as one of the new Li-ion batteries (LIBs) anode materials. Nevertheless, the poor mechanical properties and elastic stiffness of BlackP obviously limit its practical application. Thus, owing to the excellent mechanical properties and good elastic stiffness exhibited by Graphdiyne (GDY), the BlackP/GDY Van der Waals (vdW) heterostructure was investigated in our study to overcome those disadvantages on the basis of the density functional theory (DFT). Our results suggest that the BlackP/GDY vdW heterostructure has favorable mechanical properties and high thermodynamic stability with a small lattice mismatch, which is owing to the synergistic effect existed in BlackP and GDY. Besides, the adsorption energy of Li adsorption on the BlackP/GDY vdW heterostructure evidently enhanced along with the changing of the heterostructure from semiconductor to metallic. Moreover, the maximum theoretical storage capacity (384.703 mA h/g) of the BlackP/GDY vdW heterostructure is larger than that of Graphite (372 mA h/g). Above all, the minimum diffusion barrier (0.083 eV) is extremely low, which is vital for achieving ultrafast charge and discharge rates. These favorable advantages suggest that the BlackP/GDY vdW heterostructure is a viable ultrafast LIBs anode material.

Multiwalled-Carbon-Nanotube-Modified Li2ZnTi3O8 as Anode with Improved Cycling Stability and Rate Capability for Lithium-Ion Batteries

Due to its better electronic conductivity and larger lithium intercalation capacity, a multiwalled-carbon-nanotube (MWCNT)-modified Li2ZnTi3O8 (LZTO) has significant potential for use as an anode material for Li-ion batteries. The rapid and affordable ball-mill-aided solid state approach is used to synthesize LZTO with MWCNT-modified Li2ZnTi3O8 (LZTO@MWCNTs). Electrochemical performance tests of the anode material were carried out using cyclic voltammetry (CV), galvanostatic charge-discharge measurement, and electrochemical impedance spectroscopy (EIS). The CV experiments reveal that the LZTO@MWCNT electrode has a lower anodic and cathodic peak potential difference (0.184 V) than the LZTO electrode (0.211 V) and LZTO@MWCNT electrode has better electrochemical reversibility than that of pristine electrode after five cycles utilizing the same procedure. LZTO@ MWCNTs anode material has a higher charge-discharge capacity than LZTO anode material at 0.1–5 C rates. After 100 cycles, the initial discharge capacities of LZTO@MWCNT electrode are 227 and 142 mAh g−1 at the 1C–5C rate, respectively, whereas the initial discharge capacities of LZTO electrode are only144 and 28 mAh g−1 in the same condition. The charge transfer and SEI resistance of the LZTO anode are 19.31 and 62.74 ohms, respectively, after 30 cycles at 1C, according to the EIS data. Additionally, the values for the LZTO@MWCNTs anode are 7.93 and 12.06 ohms for charge transfer and SEI resistance, respectively.

Functionalized MBenes as promising anode materials for high-performance alkali-ion batteries: a first-principles study

The discovery of novel electrode materials based on two-dimensional (2D) structures is critical for alkali metal-ion batteries. Herein, we performed first-principles computations to investigate functionalized MXenes, Mo2BT2 (T = O, S), which are also regarded as B-based MXenes, or named as MBenes, as potential anode materials for Li-ion batteries and beyond. The pristine and T-terminated Mo2BT2 (T = O, S) monolayers reveal metallic character with higher electronic conductivity and are thermodynamically stable with an intrinsic dipole moment. Both Mo2BO2 and Mo2BS2 monolayers exhibit high theoretical Li/Na/K storage capacity and low ion diffusion barriers. These findings suggest that functionalized Mo2BT2 (T = O, S) monolayers are promising for designing viable anode materials for high-performance alkali-ion batteries.

Dilithium pyridine-2, 5-dicarboxylate as potential anode material for Li-ion battery

Amongst various small molecules with different functional groups, conjugated carbonyls are the most promising materials for lithium storage at low potential. This work reports lithium storage in dilithium pyridine-2, 5-dicarboxylate small molecule. We show here that dilithium pyridine-2, 5-dicarboxylate reversibly stores 2 mol of Li-ion per molecule, giving a reversible capacity of 307 mAh/g at an average voltage of 1.0 V. The capacity retention after 500 cycles at 1C rate is 69 %. This material shows impressive rate performance with a capacity retention of 140 mAh/g at 5C rate. The inclusion of electronegative nitrogen in the benzene ring helps in improving the storage performance compared to lithium terephthalate. Further ex-situ studies demonstrate possible mechanism for reversible lithium storage. Our findings showcase that the deliberately engineered organic electrode material facilitates the development of high capacity lithium-ion battery.

A Fast-Charge Graphite Anode with a Li-Ion-Conductive, Electron/Solvent-Repelling Interface.

Graphite has been serving as the key anode material of rechargeable Li-ion batteries, yet is difficultly charged within a quarter hour while maintaining stable electrochemistry. In addition to a defective edge structure that prevents fast Li-ion entry, the high-rate performance of graphite could be hampered by co-intercalation and parasitic reduction of solvent molecules at anode/electrolyte interface. Conventional surface modification by pitch-derived carbon barely isolates the solvent and electrons, and usually lead to inadequate rate capability to meet practical fast-charge requirements. Here we show that, by applying a MoOx-MoNx layer onto graphite surface, the interface allows fast Li-ion diffusion yet blocks solvent access and electron leakage. By regulating interfacial mass and charge transfer, the modified graphite anode delivers a reversible capacity of 340.3 mAh g-1 after 4000 cycles at 6 C, showing promises in building 10-min-rechargeable batteries with a long operation life.

Large-Scale Synthesis of Highly Porous CuO/Cu2O/Cu/Carbon Derived from Aerogels for Lithium-Ion Battery Anodes.

In this work, an effective strategy for the large-scale fabrication of highly porous CuO/Cu2O/Cu/carbon (P-Cu-C) has been established. Cu-cross-linked aerogels were first continuously prepared using a continuous flow mode to form uniform beads, which were transformed into P-Cu-C with a subsequent pyrolysis process. Various pyrolysis temperatures were used to form a series of P-Cu-C including P-Cu-C-250, P-Cu-C-200, P-Cu-C-350, and P-Cu-C-450 to investigate suitable pyrolysis conversion processes. The obtained P-Cu-C series were utilized as anodes of lithium-ion batteries, in which P-Cu-C-250 exhibited a higher reversible gravimetric capacity, excellent rate capability, and superior cycle stability. The enhanced behavior of P-Cu-C-250 was benefitted from the synergistic interaction between uniformly dispersed CuO, Cu2O, Cu nanoparticles, and highly graphitized carbon with a large surface area and highly porous structure. More importantly, the preparation of P-Cu-C-250 could be scaled up by taking advantage of the continuous flow synthesis mode, which may provide pilot- or industrial-scale applications. The large-scale fabrication proposed here may give a universal method to fabricate highly porous metal oxide-carbon anode materials for electrochemical energy conversion and storage applications. Porous CuO/Cu2O/Cu/carbon derived from Cu-crosslinked aerogels was used as Li-ion battery anode materials, exhibiting a high reversible areal capacity, large gravimetric capacity, superior cycling performance, and excellent rate capacity. A continuous preparation method is established to ensure the product scaled up.

Reutilization of Silicon-Cutting Waste via Constructing Multilayer Si@SiO2@C Composites as Anode Materials for Li-Ion Batteries.

The rapid development of the photovoltaic industry has also brought some economic losses and environmental problems due to the waste generated during silicon ingot cutting. This study introduces an effective and facile method to reutilize silicon-cutting waste by constructing a multilayer Si@SiO2@C composite for Li-ion batteries via two-step annealing. The double-layer structure of the resultant composite alleviates the severe volume changes of silicon effectively, and the surrounding slightly graphitic carbon, known for its high conductivity and mechanical strength, tightly envelops the silicon nanoflakes, facilitates ion and electron transport and maintains electrode structural integrity throughout repeated charge/discharge cycles. With an optimization of the carbon content, the initial coulombic efficiency (ICE) was improved from 53% to 84%. The refined Si@SiO2@C anode exhibits outstanding cycling stability (711.4 mAh g-1 after 500 cycles) and rate performance (973.5 mAh g-1 at 2 C). This research presents a direct and cost-efficient strategy for transforming photovoltaic silicon-cutting waste into high-energy-density lithium-ion battery (LIB) anode materials.

The oxidation reaction mechanism and its kinetics for a carbonaceous precursor prepared from ethylene tar for use as an anode material for lithium-ion batteries

The oxidation reaction mechanism and its kinetics for ethylene tar were investigated in order to obtain a suitable anode material for Li-ion batteries. The oxidation of ethylene tar was divided into 3 stages (350–550, 550–700 and 700–900 K) according to the thermogravimetric curve. To reveal the oxidation reaction mechanism, the components of the gases evolved at different stages were analyzed by mass spectrometry and infrared technology. Based on these results the reaction was divided into 4 stages (323–400, 400–605, 605–750 and 750–860 K) to perform simulation calculations of the kinetics. Using the iso-conversion method (Coats-Redfern) to analyze the linear regression rates (R2) between 17 common reaction kinetics models and experimental data, an optimum reaction kinetics model for expressing the oxidation of ethylene tar was determined and the results were as follows. (1) During oxidation, the side chains of aromatic compounds first react with oxygen to form alcohols and aldehydes, leaving peroxy-radicals on aromatic rings. Subsequently, the aromatic compounds with peroxy-radicals undergo polymerization/condensation reactions to form larger molecules. (2) A fourth-order reaction model was used to describe the first 3 stages in the oxidation process, and the activation energies are 47.33, 18.69 and 9.00 kJ·mol−1 at 323–400, 400–605, 605–750 K, respectively. A three-dimensional diffusion model was applied to the fourth stage of the oxidation process, and the activation energy is 88.37 kJ·mol−1 at 750–860 K. A high softening point pitch was also produced for use as a coating of the graphite anode, and after it had been applied the capacity retention after 300 cycles increased from 51.54% to 79.07%.

Porous High-Entropy Oxide Anode Materials for Li-Ion Batteries: Preparation, Characterization, and Applications.

High-entropy oxides (HEOs), as a new type of single-phase solid solution with a multi-component design, have shown great potential when they are used as anodes in lithium-ion batteries due to four kinds of effects (thermodynamic high-entropy effect, the structural lattice distortion effect, the kinetic slow diffusion effect, and the electrochemical "cocktail effect"), leading to excellent cycling stability. Although the number of articles on the study of HEO materials has increased significantly, the latest research progress in porous HEO materials in the lithium-ion battery field has not been systematically summarized. This review outlines the progress made in recent years in the design, synthesis, and characterization of porous HEOs and focuses on phase transitions during the cycling process, the role of individual elements, and the lithium storage mechanisms disclosed through some advanced characterization techniques. Finally, the future outlook of HEOs in the energy storage field is presented, providing some guidance for researchers to further improve the design of porous HEOs.

Heterometallic-organic frameworks containing Fe(II) nodes as high-performance anode materials for Li-ion batteries

Heterometallic-organic frameworks containing Fe(II) nodes as high-performance anode materials for Li-ion batteries

CoS2 nanoparticles embedded in N-doped hollow carbon nanotubes as anode materials for high performance lithium-ion battery

CoS2 nanoparticles are effectively incorporated into N-doped hollow carbon nanotubes (CoS2@HC) through a combination of a straightforward oil bath method and a high-temperature sulfurization process. The CoS2@HC composite demonstrates exceptional electrochemical performance as an anode material in Li-ion batteries. The outstanding performance of this system can be attributed to the ingeniously designed hollow carbon nanotubes. These nanotubes not only possess high electrical conductivity, thus facilitating efficient electron transfer, but also provide ample space to accommodate volume changes. Furthermore, the ultrafine CoS2 nanoparticles embedded within the hollow carbon nanotubes offer a large surface area for effective electrolyte wetting and rapid ion diffusion during the cycling process. As a result, the CoS2@HC composite delivers a high capacity of 356.2 mAh·g−1 at 2000 mA·g−1 even after 1500 cycles, demonstrating remarkable cyclic stability.

Si Nanowires: From Model System to Practical Li-Ion Anode Material and Beyond.

Nanowire (NW)-based anodes for Li-ion batteries (LIBs) have been under investigation for more than a decade, with their unique one-dimensional (1D) morphologies and ability to transform into interconnected active material networks offering potential for enhanced cycling stability with high capacity. This is particularly true for silicon (Si)-based anodes, where issues related to large volumetric expansion can be partially mitigated and the cycle life can be enhanced. In this Perspective, we highlight the trajectory of Si NWs from a model system to practical Li-ion battery anode material and future prospects for extension to beyond Li-ion batteries. The study examines key research areas related to Si NW-based anodes, including state-of-the-art (SoA) characterization approaches followed by practical anode design considerations, including NW composite anode formation and upscaling/full-cell considerations. An outlook on the practical prospects of NW-based anodes and some future directions for study are detailed.

First-Principles Studies on Transition Metal Doped Mo2B2 as Anode Material for Li-Ion Batteries.

New two-dimensional (2D) transition-metal borides have attracted considerable interest in research on electrode materials for Li-ion batteries (LIBs) owing to their promising properties. In this study, 2D molybdenum boride (Mo2 B2 ) with and without transition metal (TM, TM=Mn, Fe, Co, Ni, Ru, and Pt) atom doping was investigated. Our results indicated that all TM-doped Mo2 B2 samples exhibited excellent electronic conductivity, similar to the intrinsic 2D Mo2 B2 metal behavior, which is highly beneficial for application in LIBs. Moreover, we found that the diffusion energy barriers of Li along paths 1 and 2 for all TM-doped Mo2 B2 samples are smaller than 0.30 and 0.24 eV of the pristine Mo2 B2 . In particular, for 2D Co-doped Mo2 B2 , the diffusion energy barriers of Li along paths 1 and 2 are reduced to 0.14 and 0.11 eV, respectively, making them the lowest Li diffusion barriers in both paths 1 and 2. This indicates that TM doping can improve the electrochemical performance of 2D Mo2 B2 and that Co-doped Mo2 B2 is a promising electrode material for LIBs. Our work not only identifies electrode materials with promising electrochemical performance but also provides guidance for the design of high-performance electrode materials for LIBs.

A Study on the Nanostructural Evolution of Bi/C Anode Materials during Their First Charge/Discharge Processes.

As a candidate anode material for Li-ion batteries, Bi-based materials have attracted extensive attention from researchers due to their high specific capacity, environmental friendliness, and simple synthesis methods. However, Bi-based anode materials are prone to causing large volume changes during charging and discharging processes, and the effect of these changes on lithium storage performance is still unclear. This work introduces that Bi/C nanocomposites are prepared by the Bi-based MOF precursor calcination method, and that the Bi/C nanocomposite maintains a high specific capacity (931.6 mAh g-1) with good multiplicative performance after 100 cycles at a current density of 100 mA g-1. The structural evolution of Bi/C anode material during the first cycle of charging and discharging is investigated using in situ synchrotron radiation SAXS. The SAXS results indicate that the multistage scatterers of Bi/C composite, used as an anode material during the first lithiation, can be classified into mesopores, interspaces, and Bi nanoparticles. The different nanostructure evolutions of three types of Bi nanoparticles were observed. It is believed that this result will help to further understand the complex reaction mechanism of Bi-based anode materials in Li-ion batteries.