High-performance Li-ion Battery Anodes Research Articles

Why Charge Rate Capability Tests Fail to Characterize Structured Electrodes in Lithium-Ion Batteries and How to Modify Them

Fast charging is one of the most essential criteria for the user acceptance of battery electric vehicles. Especially for high-loaded electrodes used in automotive applications, the rate capability is limited due to the transport limitations of lithium ions in the pores.1 Electrode structuring is a powerful tool to overcome those limitations by creating additional directed diffusion channels for lithium ions.2 Despite the frequently described reduction of the transport limitation of lithium-ion batteries,3 there are hardly any charge rate capability tests in the literature that demonstrate the improvement through structuring. Instead, most studies present discharge rate capability tests showing the desired performance increase due to structuring.4-8 This study will explain why charge rate capability tests fail to characterize electrodes in the transport-limiting C-rate range. For this purpose, graphite anodes underwent “structure calendering”, where electrodes are simultaneously mechanically structured and calendered using an embossing roller. Thus, identical electrode properties, except for the lower tortuosity, can be achieved compared to the non-structured graphite anodes that were only calendered. Despite their different tortuosities, we will show that structured and non-structured graphite anodes exhibit minimal capacity differences in the charge rate capability test. This is attributed to lithium plating, which shifts the anode potential to similar values, regardless of the transport properties of the investigated electrode. We will modify the test to characterize the charge rate capability of electrodes in the transport-limiting regime where lithium plating occurs. For this purpose, in the charge rate capability test, the current is superimposed with a sinusoidal signal and the voltage response is measured. This allows the continuous estimation of the cell impedance during charging. Previous studies have shown that this method allows to track the onset of the lithium plating reaction.9-10 Applying the modified charge rate capability test will demonstrate that this detrimental side reaction occurs significantly later in structured electrodes. Günter, F. J., & Wassiliadis, N. (2022). State of the Art of Lithium-Ion Pouch Cells in Automotive Applications: Cell Teardown and Characterization. Journal of The Electrochemical Society, 169(3), 030515. https://doi.org/10.1149/1945-7111/ac4e11Pfleging, W. (2017). A review of laser electrode processing for development and manufacturing of lithium-ion batteries. Nanophotonics, 7(3), 549–573. https://doi.org/10.1515/nanoph-2017-0044Mai, W., Usseglio-Viretta, F. L. E., Colclasure, A. M., & Smith, K. (2020). Enabling fast charging of lithium-ion batteries through secondary-/dual- pore network: Part II - numerical model. Electrochimica Acta, 341, 136013. https://doi.org/10.1016/j.electacta.2020.136013Keilhofer, J., Schaffranka, L., Wuttke, A., Günter, F., Hille, L., Dorau, F., & Daub, R. (2023). Mechanical Structuring of Lithium‐Ion Battery Electrodes Using an Embossing Roller. Energy Technology. https://doi.org/10.1002/ente.202200869Dubey, R., Zwahlen, M. D., Shynkarenko, Y., Yakunin, S., Fuerst, A., Kovalenko, M. V., & Kravchyk, K. V. (2021). Laser Patterning of High-Mass-Loading Graphite Anodes for High-Performance Li-Ion Batteries. Batteries and Supercaps, 4(3), 464–468. https://doi.org/10.1002/batt.202000253Habedank, J. B., Kriegler, J., & Zaeh, M. F. (2019). Enhanced Fast Charging and Reduced Lithium-Plating by Laser-Structured Anodes for Lithium-Ion Batteries. Journal of The Electrochemical Society, 166(16), A3940–A3949. https://doi.org/10.1149/2.1241915jesHabedank, J. B., Kraft, L., Rheinfeld, A., Krezdorn, C., Jossen, A., & Zaeh, M. F. (2018). Increasing the Discharge Rate Capability of Lithium-Ion Cells with Laser-Structured Graphite Anodes: Modeling and Simulation. Journal of The Electrochemical Society, 165(7), A1563–A1573. https://doi.org/10.1149/2.1181807jesHille, L., Xu, L., Keilhofer, J., Stock, S., Kriegler, J., & Zaeh, M. F. (2021). Laser structuring of graphite anodes and NMC cathodes – Proportionate influence on electrode characteristics and cell performance. Electrochimica Acta, 392, 139002. https://doi.org/10.1016/j.electacta.2021.139002Koseoglou, M., Tsioumas, E., Ferentinou, D., Jabbour, N., Papagiannis, D., & Mademlis, C. (2021). Lithium plating detection using dynamic electrochemical impedance spectroscopy in lithium-ion batteries. Journal of Power Sources, 512(September), 230508. https://doi.org/10.1016/j.jpowsour.2021.230508Straßer, A., Adam, A., & Li, J. (2023). In operando detection of Lithium plating via electrochemical impedance spectroscopy for automotive batteries. Journal of Power Sources, 580(July), 233366. https://doi.org/10.1016/j.jpowsour.2023.233366

Optimizing Hard Carbon Anodes from Agricultural Biomass for Superior Lithium and Sodium Ion Battery Performance.

Biomass-derived carbon materials are gaining attention for their environmental and economic advantages in waste resource recovery, particularly for their potential as high-energy materials for alkali metal ion storage. However, ensuring the reliability of secondary battery anodes remains a significant hurdle. Here, we report Areca Catechu sheath-inner part derived carbon (referred to as ASIC) as a high-performance anode for both rechargeable Li-ion (LIBs) and Na-ion batteries (SIBs). We explore the microstructure and electrochemical performance of ASIC materials synthesized at various pyrolysis temperatures ranging from 700 to 1400 °C. ASIC-9, pyrolyzed at 900 °C, exhibits multilayer stacked sheets with the highest specific surface area, and the least lateral size and stacking height. ASIC-14, pyrolyzed at 1400 °C, demonstrates the most ordered carbon structure with the least defect concentration and the highest stacking height and an increased lateral size. ASIC-9 achieves the highest capacities (676 mAh/g at 0.134C) and rate performance (94 mAh/g at 13.4C) for hosting Li+ ions, while ASIC-14 exhibits superior electrochemical performance for hosting Na+ ions, maintaining a high specific capacity after 300 cycles with over 99.5% Coulombic efficiency. This comprehensive understanding of structure-property relationships paves the way for the practical utilization of biomass-derived carbon in various battery applications.

MOFite: A High-Density Lithiophilic and Scalable Metal-Organic Framework Anode for Rechargeable Lithium-Ion Battery.

Developing an anode material that has better performance efficiency than commercial graphite while keeping the features of economic scalability and environmental safety is highly desirable yet challenging. MOFs are a promising addition to the ongoing efforts, however, the relatively poor performance, chemical instability, and large-scale economic production of efficiency-proven pristine MOFs restrict their utility in real-life energy storage applications. Furthermore, hierarchical porosity for lucid mass diffusion, high-density lithiophilic sites are some of the structural parameters for improving the electrode performance. Herein, we have demonstrated the potential of economically scalable salicylaldehydate 3D-conjugated-MOF (Fe-Tp) as a high-performance anode in Li-ion batteries: the anode-specific capacity achieved up to 1447 mA h g-1 at 0.1 A g-1 and 89% of cyclic stability after 500 cycles at 1.0 A g-1.for pristine MOF. More importantly, incorporating 10% Fe-Tp doping in commercial graphite (MOFite) significantly enhanced lithium storage, doubling capacitance after 400 cycles. It signifies the potential practical utility of Fe-Tp as a performance booster for commercial anode material.

Multi-Doping Exploration of (Sb, Bi and Ba) by First Principles on Ordered Zn–Si–P Compounds as High-Performance Anodes for Next-Generation Li-Ion Batteries

Chalcopyrite ZnSiP2 has emerged as a promising anode material for next generation Li-ion-based batteries due to its high theoretical capacity. First principles multiple-dopant effect computations were made on the structural, electronic, magnetic, and thermodynamic responses for chalcopyrite ZnSiP2(1−x)Sbx, ZnSiP2(1−x)Bix, Zn(1−x)BaxSiP2, and Zn1−xBaxSiP2(1−x)Sbx, using both the norm conserving, ultra-soft pseudopotentials with generalized gradient approximation (GGA+PBE) and the main frame of density functional theory. Lattice coefficient volume, bulk modulus, formation energy, and total energy of host materials were computed and compared with experimental and theoretical results. Energy band gap for the pure chalcopyrite ZnSiP2 system (1.4 eV) matches previous data and validates the accuracy of current calculations as doping concentration (x = 0.6, 0.9, and 0.12) of (Sb, Bi, and Ba) at Zn and P sites increases. The corresponding band gap decreases, resulting in greater enhancement in electronic conductivity. Finally, the phonon dispersion relation, phonon density of states, vibration frequencies of phonon, Gibbs free energy, enthalpy, entropy effect, and Debye temperature (θ D) were estimated to confirm the thermodynamic stability of both pure and doped systems. These investigations are predicted to contribute a deeper sympathy of the doping effects on ZnSiP2, facilitating further advancements in anode materials design for Li-ion batteries.

Synergistic structure and oxygen-vacancies engineering of lithium vanadate for kinetically accelerated and pseudocapacitance-dominated lithium storage

The high reversibility, capacity, and safety make lithium vanadate (LVO) an attractive anode to Li-ion batteries, yet they still suffer from the low intrinsic electrical conductivity and ion diffusion rate. Modulating the electronic and crystal structure of materials by vacancies engineering could significantly affect the lithium storage performance. Herein, high concentration of oxygen-vacancies incorporated Li3VO4 nanowires (HLVO) were prepared to make up conductivity and ion diffusion kinetics of LVO as a competitive fast-charging anode. The oxygen-vacancies were derived from the controllable oxidation of local V4+ ions via the thermal treatment, enabling the redistribution of electrons and optimized charge‐transport properties of LVO on the basis of the experimental results and theoretical calculations. The reduced reaction energy barriers, enhanced Li-ion diffusion, improved electrical conductivity, and additional active sites induced by oxygen-vacancies drastically accelerate the redox kinetics, enhancing the capacitive behavior. Thus, the HLVO anode delivers superior electrochemical performance with large specific capacities of 553.8 mA h g−1, exceptional rate capacity of 312.2 mA h g−1 even at 4.0 A g−1 and excellent cycling stability. This finding provides the credence to the prospect of vacancy engineering contributing to develop the matter-of-fact transition metal oxides as high-performance anodes for Li-ion batteries.

Encapsulating biomass-derived SiOx with internal conductive channels in nitrogen-doped flexible carbon cages for high performance Li ion-battery anodes

N-doped flexible porous carbon encapsulated SiOx/C (p-NC/SiOx/C-3) was synthesized using rice husks as both the silicon and carbon source. When utilized as an anode for lithium ion batteries, p-NC/SiOx/C-3 delivers excellent cycling performance.

Cost-Effective Milled Silicon and Exfoliated Graphene Anode for High-Performance Li-Ion Batteries

Lithium-ion batteries play a significant role in modern electronics and electric vehicles. However, current lithium-ion battery chemistries are unable to satisfy the increasingly heightened expectations regarding energy demand and reliability. To boost the overall energy density while ensuring the safety of Li batteries, researchers have focused on developing the battery materials [1]. Silicon has an ultrahigh theoretical capacity and has been regarded as the best choice for next-generation lithium-ion battery anodes, but it also suffers from dramatic expansion during cycling [2]. Hence mitigating volume expansion is one of the main challenges towards developing a successful Si based anodes. Herein, a facile air-controlled electrospray method to directly deposit silicon/graphene (Si/Gr) onto current collectors was described. This method is inspired by an electrospinning process and possesses all the advantages that electrospinning has such as low cost, easy scaling up, and simultaneous solvent evaporation during the spraying process. Cost-effective silicon/graphene (Si/Gr) composite electrodes have been investigated for the multiple benefits of Gr in providing mechanical integrity to buffer the silicon volume expansion while maintaining electronic contact with Si to provide a Li-ion transport pathway and to form a uniform solid electrolyte interface (SEI) layer. Our results revealed a superior battery performance including a capacity of 1000 mAh/g at 2C rates and minor capacity loss during long cycling. The details of synthesis, characterization, and lithium-ion battery results of the hybrid anodes will be presented.

Porous carbon with the synergistic effect of cellulose fibers and MOFs as the anode for high-performance Li-ion batteries

The commercial graphene for Li ion batteries (LIBs) has high cost and low capacity. Therefore, it is necessary to develop a novel carbon anode. The cellulose nanowires (CNWs), which has advantages of low cost, high carbon content, is thought as a good carbon precursor. However, direct carbonization of CNWs leads to low surface area and less mesopores due to its easy aggregation. Herein, the metal-organic frameworks (MOFs) have been explored as templates to prepare porous carbon due to their 3D open pore structures. The porous carbon was developed with the coordination effect of CNWs and MOFs. The precursor of MOFs coordinates with the −OH and − COOH groups in the CNWs to provide stable structure. And the MOFs was grown in situ on CNWs to reduce aggregation and provide higher porosity. The results show that the porous carbon has high specific capacity and fast Li+/electronic conductivity. As anode for LIBs, it displays 698 mAh g−1 and the capacity retention is 85 % after 200 cycles. When using in the full-battery system, it exhibits energy density of 480 Wh kg−1, suggesting good application value. This work provides a low-cost method to synthesize porous carbon with fast Li+/electronic conductivity for high-performance LIBs.

Cobalt Oxide 2D Nanosheets Formed at a Polarized Liquid|Liquid Interface toward High-Performance Li-Ion and Na-Ion Battery Anodes.

Cobalt oxide (Co3O4)-based nanostructures have the potential as low-cost materials for lithium-ion (Li-ion) and sodium-ion (Na-ion) battery anodes with a theoretical capacity of 890 mAh/g. Here, we demonstrate a novel method for the production of Co3O4 nanoplatelets. This involves the growth of flower-like cobalt oxyhydroxide (CoOOH) nanostructures at a polarized liquid|liquid interface, followed by conversion to flower-like Co3O4 via calcination. Finally, sonication is used to break up the flower-like Co3O4 nanostructures into two-dimensional (2D) nanoplatelets with lateral sizes of 20-100 nm. Nanoplatelets of Co3O4 can be easily mixed with carbon nanotubes to create nanocomposite anodes, which can be used for Li-ion and Na-ion battery anodes without any additional binder or conductive additive. The resultant electrodes display impressive low-rate capacities (at 125 mA/g) of 1108 and 1083 mAh/g, for Li-ion and Na-ion anodes, respectively, and stable cycling ability over >200 cycles. Detailed quantitative rate analysis clearly shows that Li-ion-storing anodes charge roughly five times faster than Na-ion-storing anodes.

Core–shell Cu1−x NCo3−y /a-CuFeCo antiperovskite as high-performance anode for Li-ion batteries

Currently, there is an emergent interest in the antiperovskite family of materials in the context of energy applications in view of their distinct and peculiar set of structural and electronic properties. This work examines the surface-modified antiperovskite nitride CuNCo3 as a high-performance anode material for Li-ion storage devices. The antiperovskite CuNCo3 was prepared by the hydrothermal method followed by calcination in the NH3 atmosphere. An amorphous layer on the surface of CuNCo3 (Cu1−x NCo3−y /a-CuFeCo) was also fabricated to enhance its performance as an anode material for Li-ion batteries. The surface-modified Cu1−x NCo3−y /a-CuFeCo material was noted to deliver an extraordinarily high reversible capacity of ∼1150 mAh g−1 at a current density of 0.1 A g−1, whereas the CuNCo3 showed a reversible capacity of ∼408 mAh g−1 at the same current density. The initial capacity of Cu1−x NCo3−y /a-CuFeCo exhibited excellent retention (>62%) even after 350 cycles. A ∼6 nm thin amorphous layer around the surface of pure CuNCo3 helped almost double the specific capacity as compared to the pure CuNCo3 due to the presence of a multi-redox center for Li-ion to react and also concomitantly improved electrical conductivity property. The cyclic stability of the Cu1−x NCo3−y /a-CuFeCo material at a higher current density (0.5 and 1.0 A g−1) was also noticeable. This work opens up new materials routes and promising processing strategies to develop high reversible capacity anodes for alkali ion batteries.

Fe-N-C decorated fibrous network-wrapped biomass SiOx/C with gradient conductive structure for high performance Li-ion battery anodes

Fabrication of high performance silicon-based materials derived from natural biowastes plays a significant role in the green recycling of biomass resources. However, low utilization of organic component and poor lifespan hinders the its large scale applications. Herein, biomass derived SiOx/C-3 composite was encapsulated into Fe-N-C decorated carbon nanofibers network (Fe-N-C/SiOx/C-3) by a facile magnesiothermic reduction combined with electrostatic spinning strategy. The ingenious designed indirect contact biomass carbon/SiO2 interface effectively utilizes the organic components of rice husk and prevents the formation of SiC during reduction process. HAADF-STEM and XPS characterization confirmed the presence of Fe single atoms and the formation of Fe-N coordination bonds. Benefiting from the unique carbonaceous network and catalytic effect of Fe-N-C, the Fe-N-C/SiOx/C-3 exhibit excellent lithium storage properties (832.6 mAh g−1 after 250 cycles at 0.1 A g−1). Even at high current density (1 A g−1), the electrode can still remain a capacity of 602 mAh g−1 after 1000 cycles with capacity retention of 79.4%. The ex-situ SEM and XPS characterizations demonstrated that the gradient structure consisting of inner biomass-derived carbon and flexible carbonaceous networks enhanced the overall conductivity and structural integrity of the composite. Furthermore, the catalytic effect of Fe-N-C facilitates the rapidly formation of stable LiF-rich solid electrolyte interphase (SEI) films during charge/discharge process. The assembled LiFePO4‖Fe-N-C/SiOx/C-3 full cell shows excellent electrochemical performance (106.5 mAh g−1 after 100 cycles at 0.1A g−1), which provides insights into the fabrication of high performance biomass derived silicon based anodes.

Advancements in anode and cathode nanomaterials for high-performance Li-ion batteries

Commercially, lithium-ion batteries are the most popular batteries for electric devices, while energy density and stability have become more important for electric vehicles. Therefore, there is an increased interest in producing advanced lithium-ion batteries with a greater range of electric storage capability and improved electron transfer efficiency. Over the past few years, nanotechnology has been widely applied to enhance the physical properties of materials through the application of surface treatments or the modification of nanostructures. The significant development potential of nanotechnic applications for lithium-ion batteries is the reason for this discussion. There have been several advancements in graphene, carbon nanotubes, silicon-based and other metal-based anodes, lithium cobalt oxide, lithium iron phosphate, and nickel-based cathodes, their fabrication processes and understanding of mechanisms, as well as trends for further improvement of those previously discovered. These advancements have led to the development of batteries with greater capacity and greater performance, better stability, quicker charging times, and a longer cycle life.

Layered GeSe/thermally-reduced graphene oxide composites as efficient anodes for high-performance Li-ion batteries

Due to their layered structure and greater electrical conductivity compared to traditional metal oxides, layered metal selenides have been extensively explored as promising electrode materials for Li-ion batteries. The greatest obstacles to their continued growth, however, are the substantial volume change and particle agglomeration during cycling. In this work, layered GeSe/ thermally-reduced graphene oxide (TRG) composites were successfully synthesized by using a facile shear-force exfoliation approach. When a highly conductive TRG matrix was incorporated with GeSe particles, the resultant GeSe/TRG composite electrode achieved an impressive reversible capacity (>840.1 mAh g−1 at 0.1C), improved rate capability as well as excellent cycling stability. The remarkable improvement in electrochemical performance of the GeSe/TRG composite electrode corresponds to the TRG matrix, which potentially constructs an efficient conductive channel and serves as a flexible mechanical buffer for the restriction of volume expansion and particle aggregation.

Metal oxide- and metal-loaded mesoporous carbon for practical high-performance Li-ion battery anodes

The rapidly expanding Li-ion battery market needs new materials that can satisfy the increasing energy storage demand. Metal oxides and some metals such as tin are viable alternatives to graphite as Li-ion battery anodes, but their low conductivity and large volume change during cycling impose severe challenges that need to be overcome. Confinement of metal oxide and metal nanomaterials within mesoporous carbon (MC) is an effective strategy in this regard, but complex synthesis and nanoparticle aggregation have hindered its application. Herein, we report a facile, scalable and generalized methodology for the room-temperature synthesis of metal oxide and metal nanoparticles within a MC host. The approach has been successfully applied to achieve uniform distribution and prevent aggregation of a large variety of metal oxide and metal nanomaterials in MC support. These nanocomposites were screened as Li-ion battery anodes, and the optimal candidates were shown to be superior to previously reported systems. Our synthesis method was scaled up using commercial MC. The nanocomposites were validated in a high-loading electrode (4 mg/cm2) with a practical voltage range (< 2 V vs. Li+/Li), showing impressive initial Coulombic efficiency (> 100%), and excellent stability (∼ 500 mAh/g after 250 cycles at 0.2 A/g), which was 1.5–2x better than commercial graphite at the same testing conditions. The facile nature, universality and versatility of our approach make it possible to load various metal oxide and metal nanomaterials within different types of MC. These nanocomposites would be of significant interest to different fields, such as energy storage and conversion, sensing, and catalysis.

Candle soot-metal-organic framework-based hierarchical electrode as high-performance anode for Li-ion batteries

Recently, cobalt oxide-based materials have been considered high-performance anode materials. However, cobalt oxide materials display drawbacks such as capacity fade, poor cycle life, and substantial structural strain. In this work, we report a facile synthesis of carbon-cobalt oxide composite to improve the electrode's storage capabilities and cycle life. First, metal–organic framework-based cobalt oxide nano leaves are synthesized by simple coprecipitation followed by calcination. After that, candle soot-derived carbon nanoparticles are uniformly deposited on the cobalt oxide nano leaves by a simple flame synthesis method to form a composite electrode. The fractal-like interconnected carbon nanoparticles improve the electron conducting pathways. In contrast, metal–organic framework-derived porous cobalt oxide nano leaves enhance energy storage abilities through reversible conversion reactions. The superior performance of the composite electrode is established from the galvanostatic charge–discharge experiments. Also, the composite electrode has delivered outstanding specific capacities of 811 and 503 mAh g−1 at 50 and 1000 mA g−1 current densities, respectively. Furthermore, the composite electrode exhibited good cyclic stability at 1000 mA g−1 current density by delivering an excellent specific charge capacity of 490 mAh g−1 even after 400 cycles. Therefore, these superior electrochemical properties confirm the potential applicability in high-performance and stable Li-ion batteries.

Freestanding and Consecutive Intermixed N-Doped Hard Carbon@Soft Carbon Fiber Architectures as Ultrastable Anodes for High-Performance Li-Ion Batteries

Freestanding and Consecutive Intermixed N-Doped Hard Carbon@Soft Carbon Fiber Architectures as Ultrastable Anodes for High-Performance Li-Ion Batteries

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.

Engineering a polyaniline nanoneedles-coated multi-layered Co3O4/NiO microsphere as high-performance Li-ion battery anode

High energy-storage Li-ion battery needs a high-capacity anode. However, current graphite-based anode doesn’t meet this requirement, thus developing high performance anode materials is highly needed and significant. Here, we provide a rational engineering of a multi-layered hollow structure combining with surface coating of polyamine (PANI) layer, forming a Co3O4/NiO@PANI hybrid using for Li-ion battery anode. PANI is able to effectively improve the conductivity of active materials; besides, PANI is flexible, which can prevent the collapse of the structure caused by volume-expansion during charge and discharge. The multi-layered morphology improves the utilization ratio of voids inside the conventional hollow structured materials, which is significant to improve capacity in practical applications. The Co3O4/NiO@PANI hybrid-based anode shows a capacity of 1049 mAh g−1 along with a Coulombic efficiency of 99.3% after 100 cycles of 0.2 A g−1. Rate-performance of Co3O4/NiO@PANI exceeds that of the bare Co3O4/NiO. It is believed that the hierarchical structure combining multi-layered hollow morphology with surface coating of conductive polymer presented here would find broad applications for developing high-performance energy-storage hybrids.

Fe2O3/carbon derived from peanut shell hybrid as an advanced anode for high performance lithium ion batteries

Carbon materials derived from biomass behave sustainability, easy availability, low cost and environmentally benign. And Fe2O3 are considered as promising anodes for high-performance Li-ion batteries (LIBs) because of their rich electrochemical properties, higher theoretical capacity (1007 mAh g−1), non-toxicity, high corrosion resistance and safety. However, the high irreversible capacity loss and poor cycling stability of Fe2O3 hinders its commercial applications in LIBs. In this work, we have developed a Fe2O3@C derived from peanut shell composite by two-step hydrothermal method and low-temperature calcination with the assistance of Fe(NO3)3. As an anode for LIBs, the Fe2O3@C composite an excellent electrochemical performance in term of the specific capacity of 1000.8 mAh g−1 at 200 mA g−1 after 100 cycles, and high rate capability of 573.5 mAh g−1 even at 1 A g−1 after 200 cycles. This enhancement could be attributed to the porous carbon matrix combined with Fe2O3 nanoparticles which could increase contact area between electrolyte and active materials, improve conductivity, and accommodate the volume variations via additional void space during cycling. This work may be provide a new approach to improve anode materials using carbon derived-from biomass with larger reversible capacity and long cycle life in LIBs.