Anode Material For Li-ion Batteries Research Articles

Colloidal hot injection synthesis of Cu2FeSnS4 nanoparticles towards an enhanced capacity anode material for Li-ion batteries

The increasing demand for portable energy storage devices has prompted a considerable exploration into advanced anode material with higher Li-ion battery capacities. Quaternary chalcopyrite semiconductors have generated significant attention as promising materials in applications such as optoelectronic devices, energy conversion, and energy storage devices. In this paper, Cu2FeSnS4 (CFTS) nanoparticles were prepared through a colloidal hot injection method (HIM). The structural analysis indicates that the CFTS nanoparticles exhibit a pure tetragonal structure characterized by high crystallinity. The morphological and elemental analysis shows the stoichiometric synthesis of CFTS nanoparticles with significant agglomeration of crystallites, accompanied by variation in size. The CFTS nanoparticles, employed as an anode material for Li-ion batteries, demonstrated significant performance characterized by high reversible capacity and stability at ambient temperature. The initial discharge capacity is achieved at 1181 mAhg−1 and retains 528 mAhg−1 during charge-discharge cycles within the voltage range of 0.005 to 3.0 V (versus Li/Li+) after 5 cycles. The CFTS nanoparticle performance findings indicate its promising implementation as an anode electrode in Li-ion batteries.

In-Plane Mesoporous 3D Flower-Like Mo2Ti2C3Clx MXene Anodes for Li-Ion Batteries: From Structure to Performance.

MXenes are known for their exceptional electrical conductivity and surface functionality, gaining interest as promising anode materials for Li-ion batteries. However, conventional 2D multilayered MXenes often exhibit limited electrochemical applicability due to slow ion transport kinetics and low structural stability. Addressing these challenges, this study develops a 3D flower-type double transition metal MXene, Mo2Ti2C3Clx, with precisely engineered in-plane mesoporosity using HF-free Lewis acid-assisted molten salt method, coupled with intercalation and freeze-drying. The molar ratio of Lewis acid to eutectic salts is meticulously controlled to create the mesoporosity, which is preserved through freeze-drying. Molecular dynamics (MD) simulations assess the impact of in-plane pore size on the structure and transport dynamics of electrolyte components. Density functional theory (DFT) shows that chlorine surface functional groups significantly reduce Li-ion diffusion barriers, thereby enhancing ion transport and battery performance. Electrochemical evaluations reveal that small-sized (2-5nm) mesoporous Mo2Ti2C3Clx achieves a specific capacity of 324 mAh g-1 at 0.2 A g-1 and maintains 97% capacity after 500 cycles at 0.5 A g-1, outperforming larger-pored (10nm) and non-porous variants. This research highlights a scalable strategy for designing mesoporous materials that optimize ion transport and structural stability, essential for advancing next-generation high-performance energy storage solutions.

DFT study of lithium adsorption on silicon quantum dots for battery applications

Understanding lithium (Li) adsorption in silicon quantum dots (SiQDs) is crucial for optimizing Li-ion battery (LIB) anode materials. We systematically investigated Li adsorption in ten hydrogenated SiQDs (Si10H16, Si14H20, Si18H24, Si22H28, Si26H30, Si30H34, Si35H36, Si39H40, Si44H42, and Si48H46) across five adsorption sites (bridge(B), on-top(T), hollow-tetrahedral inner(Tdinner), hollow-tetrahedral surface(Tdsurface), and hollow-hexagonal(Hex)), utilizing density functional theory (DFT) with the M06–2X hybrid functional and 6-31G+(d) basis set. Findings identify Tdinner as the most favorable adsorption site, with a binding energy (Ebind) of 0.80–1.00 eV, dependent on SiQD size. The adsorption site exerts a more pronounced impact on Ebind than the cluster size. Multiple adsorptions in SiQDs show increased Ebind per Li atom with Li atom number. Molecular volume changes, independent of Li atom number but site-dependent, exhibit a maximum of 2.51 %. SiQD energy gap, influencing conductivity, varies with size, larger SiQDs being more conductive, especially with Li adsorption. Conclusively, our study recommends large-sized SiQDs as optimal LIB anode materials, offering high capacity, minimal volume expansion, and reasonable conductivity. This research addresses a theoretical gap, illuminating the impact of Li adsorption on SiQD molecular volumes and electronic structures, aiding in the design of enhanced capacity silicon anodes for LIB.

Lithiophilic Multichannel Layer to Simultaneously Control the Li-Ion Flux and Li Nucleation for Stable Lithium Metal Batteries.

Although the Li metal has been gaining attention as a promising anode material for the next-generation high-energy-density rechargeable batteries owing to its high theoretical specific capacity (3860 mAh g-1), its practical use remains challenging owing to inherent issues related to Li nucleation and growth. This paper reports the fabrication of a lithiophilic multichannel layer (LML) that enables the simultaneous control of Li nucleation and growth in Li-metal batteries. The LML, composed of lithiophilic ceramic composite nanoparticles (Ag-plated Al2O3 particles), is fabricated using the electroless plating method. This LML provides numerous channels for a uniform Li-ion diffusion on a nonwoven separator. Furthermore, the lithiophilic Ag on the Li metal anode surface facing the LML induces a low overpotential during Li nucleation, resulting in a dense Li deposition. The LML enables the LiNi0.8Co0.1Mn0.1O2|| Li cells to maintain a capacity higher than 75% after 100 cycles, even at high charge/discharge rates of 5.0 C at a cutoff voltage of 4.4 V, and achieve an ultrahigh energy density of 1164 Wh kg-1. These results demonstrate that the LML is a promising solution enabling the application of Li metal as an anode material in the next-generation Li-ion batteries.

Lithiophilic Multichannel Layer to Simultaneously Control the Li-Ion Flux and Li Nucleation for Stable Lithium Metal Batteries.

Although the Li metal has been gaining attention as a promising anode material for the next-generation high-energy-density rechargeable batteries owing to its high theoretical specific capacity (3860 mAh g-1), its practical use remains challenging owing to inherent issues related to Li nucleation and growth. This paper reports the fabrication of a lithiophilic multichannel layer (LML) that enables the simultaneous control of Li nucleation and growth in Li-metal batteries. The LML, composed of lithiophilic ceramic composite nanoparticles (Ag-plated Al2O3 particles), is fabricated using the electroless plating method. This LML provides numerous channels for a uniform Li-ion diffusion on a nonwoven separator. Furthermore, the lithiophilic Ag on the Li metal anode surface facing the LML induces a low overpotential during Li nucleation, resulting in a dense Li deposition. The LML enables the LiNi0.8Co0.1Mn0.1O2|| Li cells to maintain a capacity higher than 75% after 100 cycles, even at high charge/discharge rates of 5.0 C at a cutoff voltage of 4.4 V, and achieve an ultrahigh energy density of 1164 Wh kg-1. These results demonstrate that the LML is a promising solution enabling the application of Li metal as an anode material in the next-generation Li-ion batteries.

Unveiling Electrochemical Properties of Silicon for Stable Cycling Performance of Silicon Anode Materials

Research on silicon (Si) as an anode material for Li-ion batteries has spanned two decades; however, certain electrochemical properties of Si remain unclear. Specifically, the cyclic voltammogram (CV) pattern of Li/Si cells varies from case to case, influenced not only by the material but also by the experimental conditions. In this work, slow cyclic voltammetry is employed to investigate Li/Si cells, resulting in three distinct CV patterns. It is further observed that the CV pattern, particularly during the delithiation, is contingent on the state-of-lithiation (SOL) during lithiation and correlates with the capacity fade of Li/Si cells in subsequent cycles. Additionally, it is revealed that the primary mechanism for capacity fade differs between nano-sized silicon (Si-NP) and micro-sized silicon (Si-MP). In brief, capacity fade in Li/Si-NP cells predominantly arises from parasitic reactions between the highly lithiated Li-Si alloy and electrolyte solvents, exacerbated by the large specific surface area of Si-NP materials, whereas capacity fade in Li/Si-MP cells is primarily attributed to the Li electrode rather than the Si-MP electrode due to the restricted lithiation of Si-MP materials. Finally, this work concludes that limiting the SOL of Li/Si cells offers a straightforward and effective pathway to achieving stable cycling performance.

In situ anchoring in carbon matrix of Bi2O2CO3 as a high-performance anode material for Li-ion batteries

In situ anchoring in carbon matrix of Bi2O2CO3 as a high-performance anode material for Li-ion batteries

Redox Mechanisms upon the Lithiation of Wadsley-Roth Phases.

The Wadsley-Roth family of transition metal oxide phases are a promising class of anode materials for Li-ion batteries due to their open crystal structures and their ability to intercalate Li at high rates. Unfortunately, most early transition metal oxides that adopt a Wadsley-Roth crystal structure intercalate Li at voltages that are too high for most battery applications. First-principles electronic structure calculations are performed to elucidate redox mechanisms in Wadsley-Roth phases with the aim of determining how they depend on crystal structure. A comparative study of two very distinct polymorphs of Nb2O5 reveal two redox mechanisms: (i) an atom-centered redox mechanism at early stages of Li intercalation and (ii) a redox mechanism at intermediate to high Li concentrations involving the bonding orbitals of metal-metal dimers formed by edge-sharing Nb cations. Our study motivates several design principles to guide the development of new Wadsley-Roth phases with superior electrochemical properties.

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.

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.

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.

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)3·9 H2O 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 0.1 A g−1 and a high reversible specific capacity of 373.5 mAh g−1 after 500 cycles at a current density of 2 A g−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.

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.

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.

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.