Materials For Lithium-ion Batteries Research Articles

Surface Pinning of Mn by Oxidation State Control for the Synthesis of Cobalt-Free, Ni-Rich, Core/Shell Structured Cathode Materials.

Motivated by the increasing cost, environmental concerns, and limited availability of Co, researchers are actively seeking alternative cathode materials for lithium-ion batteries. A promising strategy involves structure-modified materials, such as a NiMn core/shell system. This design leverages the high energy density of a Ni-rich core while employing an Mn-rich shell to enhance interfacial stability by suppressing unwanted reactions with the electrolyte. This approach offers improved cycling stability and reduced reliance on Co. However, the interdiffusion of Mn ions between the core and shell remains a significant challenge during synthesis. This work presents a facile approach to address the issue of Mn interdiffusion in core/shell cathode materials. The study demonstrates that partial oxidation of the precursor during the drying stage effectively enhances the Mn oxidation state. This strategy successfully suppresses Mn interdiffusion during subsequent calcination, leading to the preservation of the core/shell architecture in the final cathode material. This optimized structure mitigates interfacial reactions, enhances chemomechanical properties, and reduces crosstalk, a major contributor to rollover failure. This work presents a novel approach for synthesizing high-performance core/shell cathode materials for next-generation lithium-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.

Influence of iron phosphate on the performance of lithium iron phosphate as cathodic materials in rechargeable lithium batteries

Influence of iron phosphate on the performance of lithium iron phosphate as cathodic materials in rechargeable lithium batteries

Mo-doping modulated cationic vacancy in Zn3V2O8 with enhanced electrochemical performance for lithium-ion batteries

Given diverse redox reactions and abundant raw materials, Zn3V2O8 with high specific capacity is considered as a potential anode material for lithium-ion batteries. Same as other transition metal oxides, Zn3V2O8 suffers from infertile conductivity, sluggish ion diffusion and fast capacity loss derived from volume expansion during discharge/charge process, further hindering its application. In this work, a novel Mo doped Zn3V2O8 (Zn3V2-xMo5x/6O8) anode material with cationic vacancy (V vacancy) has been designed through a facile sol-gel method. It is found that a small Mo-doping amount has nearly no influence on the crystal structure, morphology and element valence states of Zn3V2O8. Mo doped Zn3V2O8 samples possess smaller charge transfer resistance and higher lithium ion diffusion coefficient. The results of electrochemical performance illustrate that Mo doped Zn3V2O8 can deliver higher reversible specific capacities and better rate capability compared with Zn3V2O8, which can be ascribed to the introduction of V vacancy. In particular, when Mo-doping amount is set as 0.03, the obtained Zn3V1.97Mo0.025O8 exhibits a reversible capacity of 481.1 mAh g−1 after 600 cycles at 1 A g−1. It is believed that this work could provide an effective and feasible strategy to construct high performance transition metal vanadate anode materials for lithium-ion batteries.

Deciphering the storage mechanism of biochar anchored with different morphology Mn3O4 as advanced anode material for lithium-ion batteries

Biochar is regarded as a promising lithium-ion batteries anode material, owing to its high cost-effectiveness. However, the poor specific capacity and cycling stability have limited its practical applications. A straightforward and cost-efficient solvothermal method is presented for synthesizing Mn3O4/biochar composites in this study. By adjusting solvothermal temperatures, Mn3O4 with different morphology is prepared and anchored on the biochar surface (MKAC-T) to improve the electrochemical performance. Due to the morphological effect of nanospherical Mn3O4 on the biochar surface, the MKAC-180 anode material demonstrates outstanding reversible capacity (992.5 mAh/g at 0.2 A/g), significant initial coulombic efficiency (61.1 %), stable cycling life (605.3 mAh/g at 1.0 A/g after 1000 cycles), and excellent rate performance (385.8 mAh/g at 1.6 A/g). Moreover, electro-kinetic analysis and ex-situ physicochemical characterizations are employed to illustrate the charge storage mechanisms of MKAC-180 anode. This study provides valuable insights into the “structure–activity relationship” between Mn3O4 microstructure and electrochemical performance for the Mn3O4/biochar composites, illuminating the industrial utilization of biomass carbon anode materials.

Incorporating ZIF-8-derived ZnSe into hollow carbon nanospheres as anodes for lithium-ion batteries

Transition metal selenides (TMSs) show great potential as anode materials for lithium-ion batteries (LIBs), boasting a high theoretical capacity. Nevertheless, their practical utility faces challenges, mainly stemming from significant volume changes that lead to rapid capacity decay during charge and discharge cycles. To overcome this challenge, we present a systematic approach involving the growth of uniformly dispersed ultrafine ZnSe nanoparticles derived from ZIF-8 on the surface of hollow carbon nanospheres (ZnSe@N-HCS/700). When utilized as an anode material for LIBs, the ZnSe@N-HCS/700 electrode demonstrates exceptional electrochemical performance. Specifically, it achieves a capacity of 1299 mAh g−1 after 100 cycles at a current density of 100 mA g−1 and maintains a capacity of 614 mAh g−1 even after 1800 cycles at 2500 mA g−1. The hollow structure of the composite alleviates the volume variation of ZnSe nanoparticles during charge and discharge processes, and provides a large reactive surface area, thereby significantly enhancing lithium storage capacity. In conclusion, our strategy presents an innovative approach to synthesize negative electrode materials with unique structures for LIBs.

Synergistic Engineering of CoO/MnO Heterostructures Integrated with Nitrogen-Doped Carbon Nanofibers for Lithium-Ion Batteries

The integration of heterostructures within electrode materials is pivotal for enhancing electron and Li-ion diffusion kinetics. In this study, we synthesized CoO/MnO heterostructures to enhance the electrochemical performance of MnO using a straightforward electrostatic spinning technique followed by a meticulously controlled carbonization process, which results in embedding heterostructured CoO/MnO nanoparticles within porous nitrogen-doped carbon nanofibers (CoO/MnO/NC). As confirmed by density functional theory calculations and experimental results, CoO/MnO heterostructures play a significant role in promoting Li+ ion and charge transfer, improving electronic conductivity, and reducing the adsorption energy. The accelerated electron and Li-ion diffusion kinetics, coupled with the porous nitrogen-doped carbon nanofiber structure, contribute to the exceptional electrochemical performance of the CoO/MnO/NC electrode. Specifically, the as-prepared CoO/MnO/NC exhibits a high reversible specific capacity of 936 mA h g−1 at 0.1 A g−1 after 200 cycles and an excellent high-rate capacity of 560 mA h g−1 at 5 A g−1, positioning it as a competitive anode material for lithium-ion batteries. This study underscores the critical role of electronic and Li-ion regulation facilitated by heterostructures, offering a promising pathway for designing transition metal oxide-based anode materials with high performances for lithium-ion batteries.

Balancing Ionic and Electronic Conduction at the LiFePO4 Cathode–Electrolyte Interface and Regulating Solid Electrolyte Interphase in Lithium‐Ion Batteries

AbstractRecently, in electric mobilities and stationary energy storage device applications, the development of long‐lasting, low‐cost, and high‐safety lithium‐ion batteries (LIBs) is widely studied. LiFePO4 (LFP) is a core cathode material for LIBs owing to its cost‐effectiveness and high safety. However, it exhibits low electronic conductivity and sluggish Li+ diffusion, hindering the application of LFP cathodes in high‐power battery industries. Herein, a triazole‐motivated electrolyte additive, 1‐(trimethylsilyl)−1H‐benzotriazole (TMSBTA) is presented, for mitigating iron dissolution via HF scavenging, reinforcing the robustness of the solid electrolyte interphase and constructing a cathode–electrolyte interface (CEI) to balance the ion and electron conduction of the CEI on the LFP cathode. Scanning probe microscopy performed in the conductive atomic force microscopy mode indicates that the electronically conductive CEI created by the oxidative decomposition of TMSBTA enables rapid and homogeneous lithiation and delithiation during cycling without morphological changes in the LFP particles. This study elucidates the design principles of the CEI on the LFP cathode and is expected to guide integrated electrolyte additive engineering for LFP‐containing LIBs.

Innovative green intense tetra-eutectic solvent (ITES) for recovery via occlusion co-precipitation at room temperature

Lithium iron phosphate (LiFePO4) is the widely used cathode material for safe and high-power lithium-ion batteries (LIBs) for electric vehicles (EVs). Therefore, numerous challenges to re-manufacturing, re-use, and recovery from spent LiFePO4/C are tolerated if evaluated early in the innovation process. Herein, innovative green intense tetra-eutectic solvent (ITES) has been used to recover a new Li-metal co-intercalation compound from spent LiFePO4/C cathode material, which is simple and cost-effective. The ITES leaching concerning organic solution with active hydrogen donor-acceptor salts creates a coordination environment through occlusion co-precipitate new co-intercalation compound at room temperature. Innovative green ITES-10 solution has successfully recovered a new Li-metal co-intercalation regarding the active hydrogen donor-acceptor bonding coordination environment of ITES adequate leaching solution and proposed recovery mechanism. The ICP-MS value of recovery metal (7Li) efficiency (%) of ITES-10 leaching for spent LiFePO₄/C cathode materials reaches approximately 0.452% at room temperature for recovery of new co-intercalation compound, besides the fresh LiFePO₄/C cathode materials (as reference), approximately 0.805%, respectively. Therefore, innovative ITES is considered to recover spent Li-based cathode materials in our future works concerning high leaching recovery rates below 100 °C in experimental conditions.

Characteristics and properties of anode materials for lithium-ion batteries

Lithium-ion secondary batteries (LIBs) are battery systems with high energy densities. They are essential components of todays information-rich, mobile societys portable, entertainment, computing, and telecommunications technology. After 1981, most of the research on anode materials mainly focused on the anode containing Li, such as LiAl alloy, LiC alloy, etc. These materials have high prices, unstable cycling performance, and are difficult to be commercialized. The successful commercialization of LIBs began in 1991 with SONYs manufacturing of petroleum coke-based anode materials. Among them, anode plays a crucial role in LIBs. Anode materials that have been commercialized include carbon, alloys, and lithium titanate. Lithium-ion batteries using carbon anode materials and lithium titanate anode materials can meet the needs of electric vehicles (EVs) and large-scale energy storage applications to a certain extent, and alloy anode materials can promote the energy density of LIBs. The properties of the commercialized anode materials are covered in this paper. Next generation anode materials such as silicon anode materials are also introduced.

Synergistic boost in Fe3O4 anode performance for li-ion batteries via Zn and Cu double doping and multi-walled carbon nanotube composite integration

In this study, a novel nanocomposite material comprising pure Fe3O4 (FO), doped Zn0.5Cu0.5Fe2O4-3 (ZCFO-3), and Zn0.5Cu0.5Fe2O4-3@ Multi-walled carbon nanotube (ZCFO-3@MWCNT) nanocomposite material is carefully prepared using a simple one-step hydrothermal process. Comprehensive surface and morphological analysis are conducted using X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), and High-resolution transmission electron microscopy (HRTEM), while compositional studies are investigated through Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The electrochemical performance is fully analyzed through Cyclic voltammetry (CV), Electrochemical impedance spectroscopy (EIS), rate capability tests, discharge/charge capacity, and cyclic stability evaluations. Among these three nanomaterials, ZCFO-3@MWCNT nanocomposite at 100 mA g−1 current density reveals the best performance, with a discharge capacity of 1974 mAh g–1, ZCFO-3 and FO reveal 1340 mAh g–1 and 1317 mAh g–1 respectively. After 800 cycles at 500 mA g−1 current density, ZCFO-3@MWCNT stays strong with a discharge capacity of 646 mAh g–1, while ZCFO-3 manages only 362 mAh g–1 and FO only 111 mAh g–1. After 1200 cycles at 500 mA g−1, the nanocomposite still delivers 518 mAh g–1. This study suggests that ZCFO-3@MWCNT could be a promising anode material for lithium-ion batteries.

Synergistic effect of interlayered doping and surface modification to improve the performance of Li-rich manganese-based cathode materials

Li-rich manganese-based oxides (LRMOs) with high energy density have been intensively studied, but their practical use as cathode materials for lithium-ion batteries is still impeded by the shortcomings such as low initial coulombic efficiency, voltage decay and poor rate capability. To address these issues, element Nb is selected to bulk dope and simultaneously surface modify the hierarchical Li1.20Mn0.54Co0.13Ni0.13O2 spheres in this work. Synergistic effect of Nb doping and surface modification on the crystalline structure and electrochemical performance of the resultant LRMOs is characterized in detail. The results suggest that Nb5+ ions are doped into the interlayer sites within the crystals while the LiMn2O4 and LiNb3O8 double layers are coated on the primary nanoparticles. The galvanostatic charge-discharge measurements reveal that the optimal LRMO-Nb2 sample can deliver the capacities of 286 and 167 mAh g−1 at the rates of 0.1 C and 5 C, respectively, and retains a capacity of 191 mAh g−1 at 1 C rate after 200 cycles. Ex-situ XRD patterns prove that the layered structure is strongly pillared by the interlayer-doped Nb5+ during the delithiation/lithiation processes. Especially, some lithium vacancies formed around Nb5+ ions can accelerate the diffusion of Li+ ions, which was proved by DFT calculations and experimental results. Our research demonstrates that cooperating of the interlayered doping of Nb5+ with surface coating of LiNb3O8 layer can improve rate capability and cyclability of the resultant LRMOs significantly.

Commonly used commercialized cathode materials in lithium ion batteries and the corresponding enhancement with the help of nanotechnology

Commonly used commercialized cathode materials in lithium ion batteries and the corresponding enhancement with the help of nanotechnology

Mathematical Model for a Lithium-Ion Battery with a SiO/Graphite Blended Electrode Based on a Reduced Order Model Derived Using Perturbation Theory

Abstract Silicon oxide (SiO) is a promising anode material for high-energy lithium-ion batteries, as it is made from low-cost precursors, has a potential close to that of Li, and has high theoretical specific capacity. However, the applications of SiO are limited by the intrinsic low electrical conductivity, large volume change, and low coulombic efficiency, which often lead to poor cycling performance. A common strategy to address these shortcomings is to blend SiO with graphite active materials to form a composite anode for better capacity retention. In this work, we derive a reduced order model (ROM1) using perturbation theory. We employ the multi-site, multi-reaction (MSMR) framework of a composite porous electrode blend consisting of two lithium-host materials, SiO and graphite. The ROM1 model employs a single-particle model (SPM) approach as the leading-order solution and involves the numerical analysis of a single, nonlinear partial differential equation for each host material that describes diffusion by means of irreversible thermodynamics, wherein chemical-potential gradients are the driving forces for the diffusion. The first-order correction treats losses other than that of the SPM.

Effect of Subtle Changes in Ni2+/Ni3+ and Particle Surface Area in LiNi0.5Mn0.5-xCoxO2 (x = 0.1 - 0.3) Cathode Materials for Lithium-Ion Batteries

Abstract In Li[Ni,Mn,Co]O2 (NMC) cathode materials, small changes in transition metal ratio and particle surface area can significantly impact capacity retention. To understand the combined effect of transition metal ratio and the particle surface area, we studied LiNi0.5Mn0.5-xCoxO2 (x = 0.1-0.3) particles with two different morphologies: dense, spherical particles and high-surface area aggregates. All compositions in this series contain the same percentage of Ni but have differing amounts of Ni2+ and Ni3+. While Ni2+ tends to induce anti-site defects predominantly in the bulk, Ni3+ promotes particle surface reconstruction, both of which negatively impact capacity retention. Upon cycling to 4.4 V for 100 cycles, we observe that particles of high surface area with high Ni3+ concentration undergo the most severe capacity degradation. However, high surface area particles with high proportion of anti-site defects undergo sluggish capacity fade. Overall, with 60% of Ni2+ and 40% of Ni3+, spherical NMC 532 particles endure the detrimental effects of anti-site defects and surface reconstruction, but neither too prominently and thus emerges as the best candidate among the studied samples. This study highlights the synergy between transition metal ratio and particle surface area and how it determines the properties of the NMC cathode materials.

Bifunctional effects of nitrogen-doped carbon quantum dots on CoS2/mesoporous carbon composites for high-performance lithium-ion batteries

Cobalt disulfide (CoS2) stands as a promising candidate for anode materials in lithium-ion batteries due to its high theoretical capacity, but it faces challenges associated with the shuttle effect of lithium polysulfide during cycling. To address these issues, zeolitic imidazolate framework (ZIF)-derived composites have been extensively explored because of distinct advantages such as the formation of nano-sized particles, heteroatom doping, and highly porous structures. However, ZIF-derived carbon supports primarily consist of ultra-micropores that can impede lithium-ion diffusion. Herein, we aimed to enhance cycling stability by introducing a nitrogen-doped carbon quantum dot (NCQD) solution derived from N-methyl-2-pyrrolidone into cobalt-based ZIF-67 to modify the porosity and dope heteroatoms of CoS2 nanoparticle-embedded heteroatom-doped carbon composites (CoS2/NSC). The mildly acidic NCQD solution resulted in the partial etching of the ZIF-67 structure, along with the deposition of NCQDs as a nitrogen source. Notably, the pore sizes could be adjusted by varying the concentration of the NCQD solution, while retaining the nitrogen functional groups during carbonization. The electrode using CoS2/NSC with the 2.8 mL NCQD pre-treatment exhibited enhanced C-rate capability with the capacity of 392 mAh/g at 2.0 A/g. Moreover, the cycling stability was improved, with a capacity retention of 77 % after 100 cycles.

Carbothermal reduction between MOF-derived carbon and spent battery powder for metal recovery: Thermogravimetric behavior and kinetic analysis

The combined hydrometallurgical and pyrometallurgical process is an innovative method for recycling spent batteries. This process includes a carbothermic reduction step that reduces the valence of valuable metals in the batteries, facilitating subsequent leaching, which is a crucial stage in the recycling process. Additionally, the use of new carbon materials in electrode materials for ternary lithium batteries, referred to as LIBs, is increasing. These materials typically have high porosity and a large specific surface area. In this study, two types of nanoporous carbon (NC) commonly used in electrodes, namely Al-PCP-800 and ZIF-8–800, were prepared to investigate their effects on the carbothermic reduction stage of recycling spent batteries. The carbothermal reduction reactions of spent LIBs powder mixed with activated carbon and the two types of NC were examined using a thermogravimetric balance (TG/DTG). Kinetic characteristics were calculated in the interval of maximum weight loss rate using five kinetic models: VM, RPM, URCM, KAS, and FWO. The kinetic analysis revealed that the KAS and FWO models, which exhibited higher correlation coefficients, more accurately described the carbothermic reduction reactions. TG analysis showed that the sample mixed with 25 % ZIF-8–800 achieved the lowest temperature at the weight loss peak for the maximum weight loss rate, 769°C at a heating rate of 20 °C/min. Additionally, the reaction activity of NC with the positive material in the spent LIBs powder was stronger than that of activated carbon. Among the models, the sample mixed with 25 % ZIF-8–800 exhibited the lowest activation energies, recorded at 171.83, 28.48, 122.22, 199.49, and 143.45 kJ/mol, respectively. XRD and XPS characterizations of the roasted products from the spent LIBs powder mixed with the three carbon materials at various roasting end temperatures demonstrated that the cathode materials initially decomposed into Mn3O4, NiO, CoO, Li2O, and Li2CO3. At higher temperatures, Mn3O4, NiO, and CoO were further reduced to MnO, pure metallic Co, and pure metallic Ni, respectively. The sample mixed with ZIF-8–800 showed the most substantial reduction of metallic elements, with the relative contents of pure metallic Ni, pure metallic Co, and low-valent Mn elements reaching 5.50 %, 4.41 %, and 71.29 %, respectively, at a final roasting temperature of 800 °C. Therefore, NC demonstrated greater reactivity in the reduction reactions with the cathode material in the spent LIBs powder, ranking in the order of ZIF-8–800 > Al-PCP-800 > activated carbon.

A fast-charging/discharging and long-term stable artificial electrode enabled by space charge storage mechanism

Lithium‐ion batteries with fast-charging/discharging properties are urgently needed for the mass adoption of electric vehicles. Here, we show that fast charging/discharging, long-term stable and high energy charge-storage properties can be realized in an artificial electrode made from a mixed electronic/ionic conductor material (Fe/LixM, where M = O, F, S, N) enabled by a space charge principle. Particularly, the Fe/Li2O electrode is able to be charged/discharged to 126 mAh g−1 in 6 s at a high current density of up to 50 A g−1, and it also shows stable cycling performance for 30,000 cycles at a current density of 10 A g−1, with a mass-loading of ~2.5 mg cm−2 of the electrode materials. This study demonstrates the critical role of the space charge storage mechanism in advancing electrochemical energy storage and provides an unconventional perspective for designing high-performance anode materials for lithium-ion batteries.

Study of binder effect on the lithium storage kinetics of copper phosphide nanotube anode

Copper phosphide (CP) stands out as a promising anode material for lithium-ion batteries due to its high theoretical capacity (1281 mAh g−1). However, the fast capacity decay of copper phosphide poses a significant challenge due to its huge volume change. Optimization of binder selection presents an effective way to harness the high lithium storage capacity of copper phosphide. In this study, copper phosphide nanotubes were synthesized using a hard template transformation method. The following investigation delved into the impact of different binders on the electrode structure and the lithium-ion storage performance of copper phosphide. Notably, employing polyacrylic acid (PAA) as a binder resulted in a stable capacity of 526.8 mAh g−1 over 400 cycles at 100 mA g−1 for the copper phosphide electrode. The remarkable lithium-ion storage property of the CP-PAA electrode is ascribed to the robust interaction between PAA and the P–O bond on the copper phosphide surface. This interaction not only mitigated volume expansion but also enhanced the kinetics of electrochemical reactions.

A comparative study on the production of Ni1/3Co1/3Mn1/3C2O4 cathode precursor material for lithium-ion batteries using batch and slug-flow reactors

The intermittent nature of the renewable energy sources drifts research interest towards various electrochemical energy storage devices, such as the lithium ion battery, which offers consistent power supply. The manufacturing cost and electrochemical performance of a battery pack largely depends on the quality of the cathode material, which further depends on the production method and its parameters. However, the traditional stirred tank-based co-precipitation manufacturing process for precursors of lithium nickel manganese cobalt oxide (NCM111) cathode suffers from inhomogeneity in the reaction environment, which leads to non-uniform morphology and particle size distribution (PSD). In this work, slug-flow-based manufacturing platform, which offers a homogeneous reaction environment, is used for the continuous production of NCM111 oxalate precursors. One of the novel features of this work is the comparative study between the quality of batch and slug-flow-derived products. The slug-flow-derived product is found to be better in terms of having bigger particle size, narrower PSD and higher tap density. The study on the single and dual-element precipitation in similar conditions to understand the co-precipitation behavior in the slug-flow manufacturing platform is also a unique feature of this work. Furthermore, the effect of NH4OH concentration and residence time (RT) on the electrochemical performance of cathode were also studied and it is found that the cathode precursors synthesized at a NH4OH concentration of 0.08 M and a RT of 2 minutes followed by lithiation shows a better electrochemical performance of 128 mAh g−1 at 0.1 C with cycling stability of more than 80% both at 0.5 C and 1 C.