Anode Material For Li-ion Batteries Research Articles

Sustainable Li-ion anode material from Fe-catalyzed graphitization of paper waste

A novel method for the conversion of paper towel waste to biographite anode material is developed and optimized for use in Li-ion batteries. The surge in demand for Li-ion battery anode materials coupled with the unsustainable and inefficient methods of producing battery-grade graphite necessitate alternative carbon feedstocks and graphitization technologies. Paper waste (PW) is identified as a suitable carbon feedstock for iron-catalyzed graphitization due to its sustainability, low cost, low ash content, and ample supply for the intended end use. A Box Behnken experimental design for statistical optimization is pursued for untreated and pre‑carbonized PW with factors of temperature (1100–1300 °C), hold time (1–5 h), and iron catalyst loading (0.5–1.5× fixed carbon content) with biographite crystal size as the primary response variable. Temperature and iron catalyst loading are found to be significant factors, whereas hold time is found to be insignificant. Reversible capacities of the biographite anodes are found to be 340–355 mAh g−1 with 99 % capacity retention over 100 cycles, indicating good electrochemical performance relative to commercial graphite anodes. The initial Coulombic efficiency of untreated and pre‑carbonized biographites, however, are 77 % and 75 %, respectively, suggesting parasitic reactions including electrolyte decomposition.

Design and Performance of a New Zn0.5Mg0.5FeMnO4 Porous Spinel as Anode Material for Li-Ion Batteries.

Due to the low capacity, low working potential, and lithium coating at fast charging rates of graphite material as an anode for Li-ion batteries (LIBs), it is necessary to develop novel anode materials for LIBs with higher capacity, excellent electrochemical stability, and good safety. Among different transition-metal oxides, AB2O4 spinel oxides are promising anode materials for LIBs due to their high theoretical capacities, environmental friendliness, high abundance, and low cost. In this work, a novel, porous Zn0.5Mg0.5FeMnO4 spinel oxide was successfully prepared via the sol-gel method and then studied as an anode material for Li-ion batteries (LIBs). Its crystal structure, morphology, and electrochemical properties were, respectively, analyzed through X-ray diffraction, high-resolution scanning electron microscopy, and cyclic voltammetry/galvanostatic discharge/charge measurements. From the X-ray diffraction, Zn0.5Mg0.5FeMnO4 spinel oxide was found to crystallize in the cubic structure with Fd3¯m symmetry. However, the Zn0.5Mg0.5FeMnO4 spinel oxide exhibited a porous morphology formed by interconnected 3D nanoparticles. The porous Zn0.5Mg0.5FeMnO4 anode showed good cycling stability in its capacity during the initial 40 cycles with a retention capacity of 484.1 mAh g-1 after 40 cycles at a current density of 150 mA g-1, followed by a gradual decrease in the range of 40-80 cycles, which led to reaching a specific capacity close to 300.0 mAh g-1 after 80 cycles. The electrochemical reactions of the lithiation/delithiation processes and the lithium-ion storage mechanism are discussed and extracted from the cyclic voltammetry curves.

Chemical and Structural Factors Affecting the Stability of Wadsley-Roth Block Phases.

Wadsley-Roth phases have emerged as highly promising anode materials for Li-ion batteries and are an important class of phases that can form as part of the oxide scales of refractory multiprinciple element alloys. An algorithmic approach is described to systematically enumerate two classes of Wadsley-Roth crystallographic shear structures. An analysis of algorithmically generated Wadsley-Roth phases reveals that a diverse set of oxide crystal structures belongs to the Wadsley-Roth family of phases. First-principles calculations enable the identification of crystallographic and chemical factors that affect Wadsley-Roth phase stability, pointing in particular to the importance of the number and nature of the edges shared by neighboring metal-oxygen octahedra. A systematic study of Wadsley-Roth phases in the Ti-Nb-O ternary system shows that the cations with the highest oxidation states segregate to octahedral sites that minimize the number of shared edges, while cations with the lowest oxidation state accumulate to edge-sharing octahedra at shear boundaries.

Theoretical studies of C3N3Li/graphene heterostructure as a promising anode material of lithium-ion battery

The electrochemical properties of g-CN and g-CN/graphene heterostructure as anode materials for lithium-ion batteries were investigated by density functional calculations. It is shown that the Li adsorbed in the pore of g-CN has strong interactions with g-CN and a high diffusion energy barrier, leading to Li being trapped in the pores. After the pores of g-CN are fully adsorbed (C3N3Li), the migration energy barrier of Li ion on the surface of C3N3Li decreased to 0.56 eV. The calculated capacity (197 mAh/g) using C3N3Li as the host system is in agreement with experiment results. Similarly, the adsorption energy of Li in the pore of g-CN in the g-CN/graphene heterostructure is − 2.74 eV and the diffusion energy barrier (2.44 eV) for Li ion is still too high to migrate in the adjacent pores. Therefore, C3N3Li/graphene was used as the host anode system, and suitable adsorption energies (−0.81 eV), low migration energy barrier (0.43 eV), and a capacity of 694 mAh/g were obtained, which suggests that C3N3Li/graphene can be a promising anode material for Li-ion battery.

Synthesis and electrochemical properties of nano-Si/C composite anodes for lithium-ion batteries

Phenolic resin was coated on the surface of nano-Si by a microencapsulation technique, and then carbonized under Ar protection to prepare a nano-Si/C composite. The composites were first prepared using 4 different mass ratios (1:2, 1:4, 1:6, 1:8) of phenolic resin to nano-Si. The obtained average thicknesses of amorphous carbon coating were 7, 4.5, 3.7, 2.8 nm, respectively. By comparing the cycling and rate capability, the best electrochemical performance was obtained when this ratio was 1:4, with a 4.5 nm amorphous carbon coating. The electrochemical properties of this material were then comprehensively evaluated, showing excellent electrochemical performance as an anode material for Li-ion batteries. At a current density of 100 mAg−1, the material had a first specific discharge capacity of 2 382 mAhg−1, a first charge specific capacity of 1667 mAhg−1, and an initial coulombic efficiency of 70%. A discharge specific capacity of 835.6 mAhg−1 was retained after 200 cycles with a high coulombic efficiency of 99.2%. In addition, the nano-Si/C composite demonstrated superior rate performance. Under current densities of 100, 200, 500, 1 000 and 2 000 mAg−1, the average specific discharge capacities were 1 716.4, 1 231.6, 911.7, 676.1 and 339.8 mAh g−1, respectively. When the current density returned to 100 mA g−1, the specific capacity returned to 1 326.4 mAh g−1.

Correlation between microstructure, thermodynamic stability, and electric work of tin sulfide active anode materials for Li-ion batteries

The precipitation and hydrothermal synthesis methods were utilized to prepare phase pure SnS and SnS2 materials with different degrees of crystallinity, particle sizes, and morphology. The crystallite size, morphology, and phase composition of the as-synthesized materials were determined. The limiting molar enthalpies of solution of sulfur, the as-prepared materials, and that of a commercially available, macro-crystalline SnS2 in tin were established by drop calorimetry and subsequently, the enthalpies of formation were derived. The obtained enthalpies of formation of SnS range from − 48.8 to − 52.8 kJ mol−1 of atoms and for SnS2 from − 50.2–51.0 kJ mol−1 of atoms, which aligns well with existing literature results. For SnS, a trend towards less exothermic enthalpy of formation with decreasing crystallite size was observed. The obtained data of the as-prepared SnS2 materials did not clearly show such a trend and were further compared to that from commercially available, macro-crystalline SnS2. The obtained enthalpy of formation was even less exothermic compared to as-prepared SnS2 materials. After ball-milling of macro-crystalline SnS2 its formation enthalpy was the most exothermic of all SnS2 samples. An explanation of these unexpected results is given based on the energetics of crystallite size versus particle shape and size. Furthermore, the as synthesized and purchased materials were subjected to electrochemical discharge tests, and from the resulting voltage (as a function of x in LixSnS and LixSnS2) curves, the electrochemical work of the lithiation reactions was derived.

Eco-saving and green anode materials for Li-ion batteries utilizing oxide-decorated biocarbon substrates proceeded from cassava residues

In this work, an eco-saving and green anode structure (CRC) of MnO/Mn3O4 nanoparticles (NPs) anchored on biocarbon substrates derived from cassava residues (CRs) was designed and fabricated successfully by an in-situ method from MnCl2 and CRs. The amount of MnO/Mn3O4 NPs in the CRC can be effectively modulated by altering the mass ratio of MnCl2 to CRs. In Li-ion batteries, CRC anodes exhibit outstanding electrochemical performances such as high Coulombic efficiency, high capacity, excellent rate capacity, and stable cycling. The high reversible capacity of 698 mAh g−1 at 100 mA g−1 can be achieved even after 100 cycles. This could be accredited to the special structure of MnO/Mn3O4 NPs and biocarbon substrates. First, CR-derived biocarbon favors the alleviation of volume change and prevents the aggregation of MnO/Mn3O4 NPs during cycling. Then, an appropriate amount of MnO/Mn3O4 NPs formed on the surface and empty cages of biocarbon generate various free contacting channels between the electrolyte and active materials. Finally, MnO/Mn3O4 NPs intensify the electrochemical activity of biocarbon, leading to an increase in Li-storage capacities. Therefore, the facile in-situ method in this work is quite promising to produce cost-effective and eco-friendly anodes for Li-ion batteries utilizing recycled CRs and simple chemicals.

Synthesis of silicon nanoparticles with various additions of inert salt as scavenger agent during reduction by the magnesiothermic method as anode lithium-ion batteries

A heat scavenger agent magnesiothermic reduction of quartz sand was used to make Si nanoparticles in a way that can be easily scaled up. Its source of SiO2 is safe for the environment, easy to get, and cheap. It can make silicon nanoparticles that work well as an anode material for Li-ion batteries. It is known that using inert salt NaCl has a better characterization of Si and electrochemical performance than KCl, KBr, and CaCl2. XRD diffractogram show 2θ are formed at 27.42°, 47.30°, 56.11°, 69.19°, and 76.37°. The surface area shows 9.75 m2/g, and the pore size is 15.35 Å. In the TEM images, it is found that the silicon shape is spherical. The electrical conductivity voltage of 1 V is 2599.33 µS/cm. The cyclic voltammetry curve during the highest oxidation is 0.57 V, and the lowest oxidation peak is 0.16 V. After the first cycle, the Rs is 4.22 Ω, and the Rct formed is 51.19 Ω. The first discharge capacity is 2599.57 mAh/g, corresponding to coulombic efficiencies at 97.12 %.

Monolayer TiC—A high-performance Dirac anode with ultralow diffusion barriers and high energy densities for Li-ion and Na-ion batteries

Two-dimensional Dirac materials have stimulated substantial research interest as binder-free anodes in metal-ion batteries, owing to their ultrahigh electronic conductivity, large specific area, and higher energy density. Here, using first-principles density functional theory calculations, we have investigated the feasibility of monolayer TiC as a potential anode material for Li/Na-ion batteries. The results indicate that monolayer TiC exhibits excellent dynamical and thermal stability. The electronic structure of monolayer TiC shows semimetallic characteristics with a Dirac cone at the M high symmetry point and the formation of Ti or C vacancies transforms the Dirac cone into a nodal loop or a nodal surface, respectively. Thus, monolayer TiC possesses superior electrical conductivity, which can be further enhanced by the formation of Ti or C vacancies in the material. Furthermore, the calculated adsorption energy values of -0.85 and -0.46 eV for Li-ion and Na-ion, respectively, indicate that Li/Na atom adsorption over monolayer TiC is a favorable process. The density of states plots show that after the adsorption of a single Li/Na atom, monolayer TiC maintains its metallic state, which is advantageous for the diffusion of stored electrons. Most remarkably, monolayer TiC exhibits energy densities of 2684 and 2015 mWh/g for Li and Na, respectively, which are significantly higher than commercial graphite and most other 2D anode materials. The fully loaded TiC anode exhibits excellent cycle stability with volume expansions as low as 0.13 and 0.11%, for Li and Na, respectively. Furthermore, an ultrafast diffusivity with low energy barriers of 0.02 and 0.10 eV is found in monolayer TiC for Li-ion and Na-ion, respectively, which suggests that it has an excellent charge/discharge capability. These exceptional properties make monolayer TiC an excellent candidate as an anode material for Li-ion and Na-ion batteries. Finally, SiC(111) has been proposed as a candidate substrate for monolayer TiC due to its minimal lattice mismatch.

Two-dimensional Ni-MOF as a high performance anode material for lithium ion batteries

Metal organic frameworks (MOFs) have attracted extensive attention as electrode materials for use in Li-ion batteries owing to their diverse structural chemistry. Herein, a new type of two-dimensional (2D) Ni-MOF is presented as a high-performance anode material for rechargeable Li-ion batteries. The layered structure endows the Ni-MOF with free channels between the inter-layers, which is beneficial to Li+ ion diffusion, making it stand out from a crowd of porous 3D molecular materials. Strikingly, when tested at 100 mA g−1, Ni-MOF demonstrates a high capacity of 765 mA h g−1. The anode material also delivers superior rate performance and good cyclability. After being charged/discharged to high rates of 2 A/g, the anode could restore its initial capability at 100 mA g−1.

Isolation of cubic Si3P4 in the form of nanocrystals.

This article describes an approach for synthesizing silicon phosphide nanoparticles with a defective zinc blende structure under mild conditions through thermal annealing of hydrogenated silicon nanoparticles with red phosphorus. The synthesized Si3P4 nanoparticles were analyzed using FTIR, XRD, electron diffraction, EDX, TEM, Raman spectroscopy, X-ray fluorescence spectrometry, and UV-vis spectrophotometry. For the isolated cubic Si3P4 phase, a cell parameter of a = 5.04 Å was determined, and the bandgap was estimated to be equal to 1.25 eV. Because of the nanoscale dimensions of the obtained Si3P4 nanoparticles, the product may exhibit several exceptional properties as a precursor for diffusion doping of wafers and as anode material for Li-ion batteries. A similar method with a hydrogenation step offers the possibility to obtain other compounds, such as silicon selenides, arsenides, and sulfides.

Graphene-based anode materials in Li-Ion batteries

Doubtlessly, one of the most used electric power storage technologies at the moment is the lithium-ion battery (LIB). Meanwhile, in order to meet increasing needs for the present LIB performance, the improvement on the anode materials of LIB is one of the major study approaches. Among a wide range of options like silicon, metal oxides, and other compounds and mixtures, this review will mainly focus on the graphene-related LIB anode materials. By discussing the preparation processes and the electrochemical performance of various types of graphene-based and graphene-coated materials that are used for the anode of LIBs, the improvements of the addition of graphene in other materials have been reviewed, and the patterns of that have been analysed. This review helps summarize the current typical research results of the electrochemical properties of LIB anode materials based on graphene and gives suggestions about the future research focus on this specific category of materials by referring to the comparison of the data reviewed.

Selenium enriched over-oxidized Mo3Se4 decorated MXene as a high-performance Li-ion battery anode material

The anode materials in Li-ion battery (LIB) are key components that define the performance of the cell. We have developed new selenium enriched and over-oxidized Mo3Se4 decorated MXene (Mo3Se4@Ti3C2Tx) composite as a promising anode material for Li-ion battery (LIB). By using selective experimental conditions, Mo3Se4@ Ti3C2Tx was successfully developed with unique structural and morphological features. When being employed as anode material in LIB, Mo3Se4@Ti3C2Tx delivered high stable reversible specific discharge capacity of 1250 mAh/g at 0.1C, which is significantly higher than traditional carbon-based anode materials. In addition, the composite retained 84.53 % of initial specific capacity when the C-rate was increased from 0.1C to 1.5C, implying excellent rate performance. The Mo3Se4@Ti3C2Tx composite also demonstrated remarkable cycling stability with negligible loss after 378 cycles. This exceptional electrochemical performance can be assigned to the exclusive architecture of Mo3Se4@Ti3C2Tx composite, leading to increase in exposure of active Li+ sites and structural stability.

Electrical bridging effects of dual-carbon microsphere frameworks in Si-based composite anodes for high-performance Li-ion batteries

Herein, the successful fabrication of a high-performance Si-based composite Li-ion battery (LIB) anode, comprising a dual-carbon framework of reduced graphene oxide (r-GO) and oxidized single-walled carbon nanohorns (o-NHs), was demonstrated using a simple and scalable spray-drying process followed by heat treatment (h-s-GO/Si/NH). The r-GO nanosheets in the h-s-GO/Si/NH anode acted as a robust spherical framework that facilitated the mechanical and electrical connection between the carbon-coated Si (c-Si) nanoparticles, homogeneous dispersion of c-Si and o-NH nanoparticles, and suppression of the volume expansion and pulverization that occur during lithiation/delithiation. Additionally, the o-NH nanoparticles incorporated in the h-s-GO/Si/NH composite served as electrical bridges between the r-GO nanosheets, resulting in enhanced electrical conductivity and effortless Li-ion shuttling. The h-s-GO/Si/NH composite anode exhibited high electrochemical performance with a very high initial gravimetric charge capacity (2961 mAh g−1 at 0.1 A g−1), stable initial Coulombic efficiency (80.6% at 0.2 A g−1), and high cycling stability (983 mAh g−1 at 0.2 A g−1 after 50 cycles). This study highlights the importance of the effective design of electrically conductive three-dimensional frameworks in Si-based composite anodes, which may contribute to the development of high-performance LIB anode materials.

Hard carbons from automotive shredder residue (ASR) as potential anode active material for sodium ion battery

Graphite, the most prominent anode material for Li-ion battery, exhibited very poor performance in sodium ion battery. The electrochemical intercalation of Na+ ions in graphite is impeded due to smaller interlayer spacing. Here, we have reported ASR derived hard carbon as a suitable anode electroactive material for Na-ion battery. Prepared via single step selective thermal transformation, the hard carbons contain defects, heteroatoms, nanopore, and ordered carbon zones with expanded interlayer spacing. Among all the hard carbons, the hard carbon synthesised at 1100 °C, showed better electrochemical performance owing to its improved structural and morphological properties. The electrochemical study reveals that hard carbon synthesised at 1100 °C provides initial reversible capacity of 434mAh/g at a current density of 10 mA/g with a capacity retention of 53% after 100 cycles. Issues like global warming and climate changes have made human to shift their energy choices from fossil fuels to renewable sources. Although Li-ion battery is currently dominating the energy market, yet it falls short to meet the growing large scale energy storage system (EES) demand. Na-ion battery is considered as a worthy contender for growing ESS. The hard carbon studied in this work, can be a potential candidate for use as anode active material in Na-ion battery.

Theoretical design of C3N/Borophene heterostructure as high-performance anode materials for Li-ion batteries

Theoretical design of C3N/Borophene heterostructure as high-performance anode materials for Li-ion batteries

Open-framework iron(II) phosphate-oxalate as anode material for Li-ion batteries

Open-framework iron(II) phosphate-oxalate as anode material for Li-ion batteries

Synthesis of a Yolk-Shell Nanostructured Silicon-Based Anode for High-Performance Li-Ion Batteries

Silicon is a desirable anode material for Li-ion batteries owing to its remarkable theoretical specific capacity of over 4000 mAh/g. Nevertheless, the poor cycling performance of pure Si electrodes caused by dramatic volume expansion has limited its practical application. To alleviate the adverse effects of Si expansion, we have synthesized anode materials of nano-Si particles trapped in a buffering space and outer carbon-based shells (Si@Void@C). The volume ratio of Si nanoparticle to void space could be adjusted accurately to approximately 1:3, which maintained the structural integrity of the as-designed nanoarchitecture during lithiation/delithiation and achieved a notable specific capacity of ~750 mAh/g for as-prepared half-cells. The yolk-shell nanostructure alleviates volumetric expansion on both material and electrode levels, which enhances the rate performance and cycling stability of the silicon-based anode.

Facile decoration of fluorinated metal–organic frameworks on copper foil for regulated lithium deposition and robust solid electrolyte interface

Lithium metal is one of the most promising anode materials for Li-ion batteries. However, lithium metal anodes suffer from low coulomb efficiency, short cycle life, and even serious safety issues, owing to the incompatible Cu/Li interface and brittle solid electrolyte interface (SEI). A facile strategy is proposed to construct stable lithium metal anodes by regulating both the Cu/Li interface and SEI membrane with a thin layer of copper-tetrafluoroterephthalate (CuTFBDC), which can guide the uniform lithium deposition and the LiF-rich SEI. The prepared CuTFBDC@Cu foils can be applied as current collectors, and the assembled Li@CuTFBDC@Cu//Li symmetric cell exhibits a stable performance at a current density of 0.5 mA cm−2 for more than 3000 h, with a small voltage hysteresis of less than 11.5 mV, surpassing that of the bare Cu foil. The assembled Li@CuTFBDC@Cu//LFP (LiFePO4) full cell proceeds smoothly for 200 cycles at a current density of 2 C with a specific capacity of 133.8 mAh/g, and the capacity can be maintained at 125.29 mAh/g after 250 cycles. This facile strategy can provide a solution for both the Cu/Li interface and SEI membrane, showing an excellent prospect for practical applications in lithium metal batteries.

Lithium-Ion Diffusivity Increases with Block Size in Niobium Tungsten Oxide Shear Structures

Nb16W5O55 emerged as a high-rate anode material for Li-ion batteries in 2018 (Griffith et al.,Nature 2018, 559 (7715), 556–563). This exciting discovery ignited research in Wadsley-Roth (W-R) compounds, but systematic experimental studies have not focused on how to tune material chemistry and structure to achieve desirable properties for energy storage applications. In this work, we systematically investigate how structure and composition influences capacity, Li-ion diffusivity, charge-discharge profiles, and capacity loss in a series of niobium tungsten oxide W-R compounds: (3×4)-Nb12WO33, (4×4)-Nb14W3O44, and (4×5)-Nb16W5O55. Potentiostatic intermittent titration (PITT) data confirmed that Li-ion diffusivity increases with block size, which can be attributed to an increasing number of tunnels for Li-ion diffusion. The small (3×4)-Nb12WO33 block size compound with preferential W ordering on tetrahedral sites exhibits single electron redox and, therefore, the smallest measured capacity despite having the largest theoretical capacity. This observation signals that introducing cation disorder (W occupancy at the octahedral sites in the block center) is a viable strategy to access multi-electron redox behavior in (3×4) Nb12WO33. The asymmetric block size compounds (i.e., (3×4) and (4×5) blocks) exhibit the greatest capacity loss after the first cycle, possibly due to Li-ion trapping at a unique low energy pocket site along the shear plane. Finally, the slope of the charge-discharge profile increases with increasing block size, likely because the total number of energy-equivalent Li-ion binding sites also increases. This unfavorable characteristic prohibits the large block sizes from delivering constant power at a fixed C-rate more so than the smaller block sizes. Based on these findings, we discuss design principles for Li-ion insertion hosts made from W-R materials.