Lithium Ion Storage Performance Research Articles

In-situ synthesis of FeV2O4@Fe3C heterostructures embedded in the carbon nanosheets for lithium ion batteries

Transition metal vanadates have become the focus of anode materials research due to their abundant raw material reserves, high theoretical capacity and higher electrochemical activity than single metal oxides. However, the shortcomings such as low electrical conductivity, severe aggregation and volume expansion can lead to poor electrochemical performance. Herein, the FeV2O4@Fe3C heterostructures embedded in the carbon nanosheets are designed and prepared, which delivers the outstanding lithium ion storage performance owing to the synergetic effect between FeV2O4 and Fe3C@C. This work could offer an effective avenue for the heterostructure design and performance improvement of anode electrodes for lithium ion batteries.

Surface-modified spinel high entropy oxide with hybrid coating-layer for enhanced cycle stability and lithium-ion storage performance.

High-entropy oxide (HEO) has emerged as a promising anode material for high-energy lithium-ion batteries (LIBs) due to its high theoretical specific capacity. However, the further application of HEO is restricted by its complicated interface problems and inevitable expansion effect. In this work, a simple approach to coat spinel HEO (FeCoNiCrMn)3O4 with a hybrid layer of lithium titanate (LTO) and carbon is presented. The coating is applied through a solution-chemistry method followed by calcination under an inert atmosphere. This hybrid layer significantly improves the electrochemical kinetics and stability at the electrode/electrolyte interface. Additionally, the diffusion of Ti4+ into the HEO bulk during synthesis provides an inactive metal skeleton, potentially improving cycle stability. Electrochemical test results show that the HEO@LTO/C achieved a reversible specific capacity of 1090 mA h g-1 at 0.5 A g-1 and remained stable after 800 cycles. Moreover, the first-coulomb efficiency was increased from 63.7% to 72.8%, and rate performance has improved by at least 100 mA h g-1. This work demonstrates that hybrid surface-modifying of HEO is an effective measure to improve and stabilize its electrochemical properties.

Exfoliation and restacking route to Keggin-Al13-treated layered ruthenium oxide for enhanced lithium ion storage performance

Ruthenium oxide nanosheets were used as hosts for the Keggin-Al13. The synthesized AR-150 has stable cycling performance as an anode material for lithium-ion batteries.

Uniformly anchoring Sb2O5 nanoparticles on graphene sheets via Co2+-induced deposition for enhanced lithium/sodium-ion storage

A Co–Sb2O5/rGO nanocomposite was prepared by a facile Co2+-induced deposition process. The interactions between Sb2O5 and rGO were enhanced by initial in situ formation of CoSb2Sb6, resulting in greatly improved lithium-ion storage performance.

Enhanced lithium-ion storage of the SiOx@C anode enabled by carbon coating coupled with MXene as a conductive binder

The MXene as a multi-functional binder, together with the carbon coating, endows the SiOx anode with excellent lithium-ion storage performance.

C@SnS2 core-shell 0D/2D nanocomposite with excellent electrochemical performance as lithium-ion battery anode

C@SnS2 core-shell 0D/2D nanocomposite was successfully prepared by a one-step hydrothermal method. The SnS2 nanosheets were heterogeneously nucleated and grown on the surface of carbon spheres. As an anode for lithium-ion batteries, the electrochemical performance of the C@SnS2 composite outperforms that of SnS2 nanoflowers. After 100 cycles, the reversible discharge specific capacity reaches an impressive value of 802 mAh g−1 at a current density of 100 mA g−1. Even after 600 cycles, the discharge specific capacity remains a value of 442 mAh g−1, under a high current density of 1 A g−1. This remarkable lithium-ion storage performance can be attributed to the unique core-shell nanostructure and the synergy between SnS2 nanosheets and carbon spheres. This study advances our understanding of the vital role of carbon in fabricating nano-heterojunction or composite electrodes and provides a feasible route to significantly improve the electrochemical properties of SnS2 and other metal sulfides.

Nitrogen-oxygen co-doped nanocarbon anodes derived from a Lewis acid-alkaline paired supermolecule structure for lithium-ion hybrid capacitors

Carbon-based material is a practical, low-cost class of anode for lithium-ion batteries (LIBs). Commercial graphite anodes exhibit restricted theoretical capacity and poor rate performance. In contrast, amorphous carbon anodes, with their large interlayer spacing and defect sites, offer superior reversible lithium-ion storage capacity. The capability of storing lithium ions can be further facilitated by enhanced surface capacitive adsorption sites through heteroatom doping strategies in concert with porous structure design. Herein, we synthesize a Lewis acid-alkaline paired supramolecule by rhodanine and melamine and produce N/O co-doped porous carbon materials (RMC) from this supramolecule by one-step carbonization method. The RMC electrodes display a high reversible lithium-ion storage capacity of 544 mAh g−1 and robust rate performance. This work presents a novel and effortless approach for the preparation of N/O co-doped porous carbon materials to be utilized as anode materials with remarkable lithium-ion storage performances.

Core-Shell Structure Trimetallic Sulfide@N-Doped Carbon Composites as Anodes for Enhanced Lithium-Ion Storage Performance.

The high specific capacity of transition metal sulfides (TMSs) opens up a promising new development direction for lithium-ion batteries with high energy storage. However, the poor conductivity and serious volume expansion during charge and discharge hinder their further development. In this work, trimetallic sulfide Zn-Co-Fe-S@nitrogen-doped carbon (Zn-Co-Fe-S@N-C) polyhedron composite with a core-shell structure is synthesized through a simple self-template method using ZnCoFe-ZIF as precursor, followed by a dopamine surface polymerization process and sulfidation during high-temperature calcination. The obvious space between the internal core and the external shell of the Zn-Co-Fe-S@N-C composites can effectively alleviate the volume expansion and shorten the diffusion path of Li ions during charge and discharge cycles. The nitrogen-doped carbon shell not only significantly improves the electrical conductivity of the material, but also strengthens the structural stability of the material. The synergistic effect between polymetallic sulfides improves the electrochemical reactivity. When used as an anode in lithium-ion batteries (LIBs), the prepared Zn-Co-Fe-S@N-C composite exhibits a high specific capacity retention (966.6 mA h g-1 after 100 cycles at current rate of 100 mA g-1) and good cyclic stability (499.17 mA h g-1 after 120 cycles at current rate of 2000 mA g-1).

Controllable preparation of wrapped Fe2O3@rGO composites and their lithium ion storage performance

In this paper, reduced graphene oxides wrapped hollow Fe2O3 spheres (Fe2O3@rGO) were successfully prepared by solvothermal method. Results show that plenty of Fe-O-C bonds between reduced graphene oxides and Fe2O3 significantly improved electron transfer rate of the composite anodes, and confinement effect of reduced graphene oxides slowed the pulverization rate of Fe2O3 during charge/discharge process. As expected, wrapped structured Fe2O3@rGO anode exhibited high rate capability of 514 mA·h/g at high current of 5.0 A/g and durable cycling life over 500 cycles with a capacity of 987 mA·h/g under 0.5 A/g with a capacity retention of 81.1%. This work provides an effective strategy for the preparation of high-rate and long-life graphene composite anode materials.

Ultrafast high-temperature sintering of high-entropy oxides with refined microstructure and superior lithium-ion storage performance

Ultrafast high-temperature sintering of high-entropy oxides with refined microstructure and superior lithium-ion storage performance

Zinc ion exchange assisted synthesis of R-TiO2@C hollow spheres with superior lithium-ion storage performance

Nanostructured anode materials hold the key to advance the performance of the corresponding lithium-ion batteries as advanced electrochemical energy storage devices. Here, we designed a zinc exchange assisted phase change strategy as an acid-free and well-controlled approach to successfully synthesize a kind of rutile phase TiO2 @C (R-TiO2 @C) hollow spheres with well-defined size by using SiO2 spheres as sacrificial templates. The exchanged zinc ions in an alcohol solvothermal reaction were considered as a phase transition medium to promote the formation of a high-quality rutile TiO2 crystal through a high temperature solid-state heat way. By this way, the final morphologies of rutile phase TiO2 nanocrystals were well controlled, and the rutile TiO2 phase transformation temperature was lower than that of conventional one-step high temperature calcination way (without zinc ions exchange). Note that it successfully avoided using acids as mediums to promote the formation of rutile phase TiO2 crystal in the nano process. Meanwhile, the carbon layer formed by a hydrothermal carbonization reaction not only provided self-supporting solid-state in situ reducing medium for Zn2+ to Zn vapor but also produced conductive porous carbon coating porous and robust R-TiO2 spherical shell with nanosized subunits. The reaction process and mechanism of zinc ions induced phase transformation were discussed. Benefiting from the nanoscale morphology-regulation and hollow structure with enhanced ability of ion and electron transfer as well as electrolyte transport, the resultant R-TiO2 @C hollow spheres can significantly promote Li ions storage and deliver a high reversible specific capacity of 115.6 mAh g-1 at 5.0 C over 1600 cycles. A typical electrochemical reaction on Li ions inserted into TiO2 crystal was simply elaborated as well. This work demonstrates its great potential for practical application in lithium-ion batteries.

Consecutive engineering of anodic graphene supported cobalt monoxide composite and cathodic nanosized lithium cobalt oxide materials with improved lithium-ion storage performances

Downsizing the electrochemically active materials in both cathodic and anodic electrodes commonly brings about enhanced lithium-ion storage performances. It is particularly meaningful to explore simplified and effective strategies for exploiting nanosized electrode materials in the advanced lithium-ion batteries. In this work, the spontaneous reaction between few-layered graphene oxide (GO) and metallic cobalt (Co) foils in mild hydrothermal condition is for the first time employed to synthesize a reduced graphene oxide (RGO) supported nanosized cobalt monoxide (CoO) anode material (CoO@RGO). Furthermore, the CoO@RGO sample is converted to nanosized lithium cobalt oxide cathode material (LiCoO2, LCO) by taking the advantages of the self-templated effect. As a result, both the CoO@RGO anode and the LCO cathode exhibit inspiring lithium-ion storage properties. In half-cells, the CoO@RGO sample maintains a reversible capacity of 740.6 mAh·g−1 after 300 cycles at the current density of 1000 mA·g−1 while the LCO sample delivers a reversible capacity of 109.1 mAh·g−1 after 100 cycles at the current density of 100 mA·g−1. In the CoO@RGO//LCO full-cells, the CoO@RGO sample delivers a reversible capacity of 553.9 mAh·g−1 after 50 cycles at the current density of 200 mA·g−1. The reasons for superior electrochemical behaviors of the samples have been revealed, and the strategy in this work can be considered to be straightforward and effective for engineering both anode and cathode materials for lithium-ion batteries.

N/O/P ternary-doped coal-based hierarchical porous carbon networks for high lithium-ion storage performance

Constructing porous structure and surface modification are effective ways to enhance the Li-ion storage performance of commercial graphite anode for lithium-ion batteries (LIBs). Herein, nitrogen, oxygen and phosphorus ternary-doped coal-based hierarchical porous carbon networks (N/O/P-CCNs) were prepared through liquid oxidation combined with self-assembly method. The N/O/P-CCNs have a three-dimensional porous carbon network structure formed by cross-linking carbon nanosheets with an appropriate specific surface area (321 m2 g−1) and distribution of micro-, meso- and macropore, while the surfaces of carbon nanosheets are doped with nitrogen, oxygen and phosphorus. Due to unique hierarchical porous structure and the synergistic effect of ternary doping, the N/O/P-CCNs anode exhibits excellent Li-ion storage properties with initial reversible capacity of 1079 mAh g−1, which is much higher than that of coal-based graphite anode (382 mAh g−1). Besides, the N/O/P-CCNs anode also has superior rate capability (336 and 275 mAh g−1 at 1.0 and 2.0 A g−1) and cycle stability with a high capacity retention (near 100 % after 100 cycles). The excellent electrochemical performance is not only related to the hierarchical pore structure that can provide efficient channels for lithium-ion transport, but also to the ternary-doping of nitrogen, oxygen and phosphorus that can provide more active sites for lithium-ion storage and enhance conductivity. This work provides a novel and effective design strategy for developing high-performance anode materials for LIBs.

Enhancing lithium-ion storage performance of hollow CoS2/MoS2 nanospheres via N-doped carbon-coating

Transition metal sulfides (TMSs) have been considered as up-and-coming anode materials for lithium-ion batteries (LIBs) owing to their large theoretical capacity and good reversibility. However, obvious volume variation and sluggish kinetics greatly limit their practical application. To address this issue, we successfully design and fabricate hollow CoS2/MoS2 nanospheres and effectively enhance their lithium storage performance via N-doped carbon-coating (CoS2/MoS2@N-C). The unique hollow structure provides shortened ion-diffusion path, while the N-doped carbon shells buffer the severe volume changes during cycling and improve the electronic conductivity of the electrode. When used as an anode material for LIBs, the CoS2/MoS2@N-C displays high specific capacity (1056.9 mA h g−1 at 100 mA g−1), excellent cycling stability (653.9 mA h g−1 after 250 cycles at 1000 mA g−1), and rate capability (685 mA h g−1 at 2000 mA g−1). The CoS2/MoS2@N-C||LiFePO4 full-cell LIB is also assembled and exhibits remarkable performance. The remarkable electrochemical performance of CoS2/MoS2@N-C electrode could be assigned to the synergistic enhancement effect of the N-doped carbon coating and hollow structure, which efficiently shorten the ion diffusion path, boost the charge transfer rate, and alleviated the volume changes of the electrode upon cycling.

Rational design of a novel polypyrrole-coated and zirconium-doped lithium vanadium phosphate with outstanding rate performance for lithium-ion storage

The inferior electrical conductivity seriously prevents the application of monoclinic Li3V2(PO4)3 (LVP) cathode in lithium energy storage. In this research, we introduce a promising strategy of polypyrrole coating and Zr4+ doping to promote the conductivity of LVP material. The Zr4+-doped and polypyrrole-coated LVP (LVZxP@PPy) electrode is synthesized by a facile way followed by an in-situ pyrrole polymerization procedure for the first time. The substitution of Zr4+ in V3+ site can enlarge the lattice volume of LVP, providing a big diffusion channel for Li+ extraction and insertion. Besides, Zr4+ doping can also promote the intrinsic conductivity of LVP, whilst polypyrrole film can greatly promote the apparent conductivity. Therefore, the as-fabricated LVZxP@PPy electrode possesses outstanding rate property for lithium energy storage. Especially, LVZ5%P@PPy displays the specific capacities of 131.5 and 115.2 mA h g−1 at 0.1 and 5C respectively between 3 and 4.3 V. Meanwhile, it shows the high capacity retention of 95.7% over 400 cycles at 10C in the potential range of 3∼4.8 V.

Hollow multi-shelled spherical Co3O4/CNTs composite as a superior anode material for lithium-ion batteries

Hollow multi-shelled spherical Co3O4/CNTs composite was prepared by a facile MOF-assisted strategy by introducing carbon nanotubes (CNTs) directly into the precursor. The hierarchical porous structure of the obtained multi-shelled Co3O4 nanospheres can effectively alleviate volume change and facilitate the infiltration of electrolyte into the interior. The interconnected CNTs can reduce the electrochemical polarization by improving the conductivity of the body material. As an anode for lithium ion batteries, the as-synthesized Co3O4/CNTs composite exhibits superior lithium ion storage performance. A high reversible specific capacity of 653.1 mAh g−1 was obtained after 500 cycles at 1000 mA g−1, suggesting a significant inspiration for fabricating application for advanced electrochemical devices.

Engineering a hierarchical reduced graphene oxide and lignosulfonate derived carbon framework supported tin dioxide nanocomposite for lithium-ion storage

Tin dioxide (SnO2) is widely recognized as a high-performance anode material for lithium-ion batteries. To simultaneously achieve satisfactory electrochemical performances and lower manufacturing costs, engineering nano-sized SnO2 and further immobilizing SnO2 with supportive carbon frameworks via eco-friendly and cost-effective approaches are challenging tasks. In this work, biomass sodium lignosulfonate (LS-Na), stannous chloride (SnCl2) and a small amount of few-layered graphene oxide (GO) are employed as raw materials to engineer a hierarchical carbon framework supported SnO2 nanocomposite. The spontaneous chelation reaction between LS-Na and SnCl2 under mild hydrothermal condition generates the corresponding SnCl2@LS sample with a uniform distribution of Sn2+ in the LS domains, and the SnCl2@LS sample is further dispersed by GO sheets via a redox coprecipitation reaction. After a thermal treatment, the SnCl2@LS@GO sample is converted to the final SnO2/LSC/RGO sample with an improved microstructure. The SnO2/LSC/RGO nanocomposite exhibits excellent lithium-ion storage performances with a high specific capacity of 938.3 mAh/g after 600 cycles at 1000 mA g−1 in half-cells and 517.1 mAh/g after 50 cycles at 200 mA g−1 in full-cells. This work provides a potential strategy of engineering biomass derived high-performance electrode materials for rechargeable batteries.

Metal-organic framework derived CdSe wrapped with rGO for enhanced lithium storage performance.

Considering the advantages of MOF-based, CdSe-based, and rGO-based materials, CdSe nanoparticles encapsulated with rGO (CdSe@rGO) were synthesized by a metal-organic framework derived method. CdSe nanoparticles encapsulated with rGO can effectively tolerate volume expansion and improve electrical conductivity, leading to excellent cycling stability (396 mAh g-1 at 0.3 A g-1 after 200 cycles, 311 mAh g-1 at 0.5 A g-1 after 500 cycles), and rate performance (562 mAh g-1 at 0.1 A g-1 and 122.2 mAh g-1 at 4 A g-1) for lithium-ion storage. This strategy for preparing metal selenides protected by carbon layers can be extended to the design of other high-performance materials.

TiO2/Ti3C2Tx composite as an anode material with ideal lithium-ion storage performance

Ti3C2Tx MXene holds great potential in anode materials of lithium-ion batteries (LIBs). However, its initial coulombic efficiency (ICE) and cycling performance are low because of its inner defects. Herein, TiO2 nanoparticles are grown in these defects, effectively suppressing solid electrolyte interface (SEI) layer growth and improving the stability of the electrode. As a result, the TiO2/Ti3C2Tx composite displays excellent electrochemical properties including a high ICE of 82.5% at 100 mA g−1, compared to 66.8% for Ti3C2Tx. Moreover, TiO2/Ti3C2Tx composite maintains a stable discharge capacity of 282.3 mAh/g at 100 mA g−1 for 200 cycles with a high-capacity retention of 81.2%, and displays a high discharge capacity of 187.4mAhg−1 at 2000 mA g−1. Our work develops an effective approach to improve the electrochemical performance of Ti3C2Tx MXene.

Solid-state mechanochemistry advancing two dimensional materials for lithium-ion storage applications: A mini review

The vigorous development of two-dimensional (2D) materials brings about numerous opportunities for lithium-ion batteries (LIBs) due to their unique 2D layered structure, large specific surface area, outstanding mechanical and flexibility properties, etc. Modern technologies for production of 2D materials include but are not limited to mechanochemical (solid-state/liquid-phase) exfoliation, the solvothermal method and chemical vapor deposition. In this review, strategies leading to the production of 2D materials via solid-state mechanochemistry featuring traditional high energy ball-milling and Sichuan University patented pan-milling are highlighted. The mechanism involving exfoliation, edge selective carbon radical generation of the 2D materials is delineated and this is followed by detailed discussion on representative mechanochemical techniques for tailored and improved lithium-ion storage performance. In the light of the advantages of the solid-state mechanochemical method, there is great promise for the commercialization of 2D materials for the next-generation high performance LIBs.