Performance Sodium-ion Batteries Research Articles

Cu-Occupied Ni-Site O3-Type Layered NaNi0.5Mn0.5O2 with Enhanced Rate Performance for Sodium-ion Batteries

Cu-Occupied Ni-Site O3-Type Layered NaNi0.5Mn0.5O2 with Enhanced Rate Performance for Sodium-ion Batteries

Effect of concentration of dextrose-derived hard carbon anode on the electrochemical performance for sodium-ion batteries

Effect of concentration of dextrose-derived hard carbon anode on the electrochemical performance for sodium-ion batteries

Two-step synthesis of hard carbons anode material from poplar wood with enhanced performance for sodium-ion batteries

Two-step synthesis of hard carbons anode material from poplar wood with enhanced performance for sodium-ion batteries

Boosting sodium-ion battery performance with vanadium substituted Fe, Ni dual doped fluorophosphate cathode over a wide temperature range

Recently, polyanionic material has been identified as the most attractive choice for the cathode in sodium-ion batteries. However, the poor electronic conductivity of Na3V2(PO4)2F3 (NVPF) limits its electrochemical performance, while the presence of vanadium increases material costs. To address these challenges, we have synthesized carbon-coated Fe, Ni dual-doped NVPF (Na3V1.9Fe0.01Ni0.09(PO4)2F3) via a rota tumbler assisted sol-gel process and reported for the first time. Comprehensive studies reveal that dual doping significantly affects the structural, morphological, and electrochemical properties of the material. Rietveld refinement shows that doping adjusts the crystal structure, enlarging Na⁺ diffusion pathways and enhancing diffusion kinetics. Na3V1.9Fe0.01Ni0.09(PO4)2F3 exhibits a superior capacity of 115.58 mAhg−1 at 0.1C, 92.86 mAhg−1 at 2C, 87.79 % cyclic retention at 2C after 500 cycles. The optimized material demonstrates robust performance across a wide temperature range (55 °C to −21.1 °C). Furthermore, full-cell constructed using Na3V1.9Fe0.01Ni0.09(PO4)2F3 as cathode and hard carbon as anode delivers an impressive capacity of 87.01 mAhg−1 at 1C and a retention of 94.50 % for 100 cycles at 0.5C. Moreover, reducing the vanadium content in the cathode helps lower the overall manufacturing costs. Our research demonstrates that Na3V1.9Fe0.01Ni0.09(PO4)2F3 is a promising option for a high-performance cathode in sodium-ion batteries.

Enhanced Na-Ion Electrochemical Performance through Cu Doping-Mediated Sb2Se3 Phase Transformation into CuSbSe2 with Improved Kinetics.

This work investigates the influence of structural and electronic modification on the electrochemical performance of conversion and alloying materials. The CuSbSe2, a promising 2D layered conversion-and-alloying material is being investigated with references to parent pristine Sb2Se3 and a doped version of later Sn0.2Sb1.8Se3 for their sodium-ion battery performance. The CuSbSe2 with layered structure is well known to accommodate lattice distortions via inter-layer movement, potentially mitigating distortions brought about by the Alkali ion (Na in this case) insertion. In contrast, the parent conversion-cum-alloying material Sb2Se3 with its one-dimensional crystal structure leads to structural disintegration during battery operation. The Sn-doped analog, Sn0.2Sb1.8Se3, comparatively exhibits enhanced kinetics owing to the reduced long-range order. The 2D layered, CuSbSe2 despite exhibiting2D long-range order exhibits superior electrochemical performance owing to the favorable electronic and structural features. The CuSbSe2 exhibits a reversible capacity of 881 mAh g-1 compared to 516 mAh g-1 for Sn0.2Sb1.8Se3 and 429 mAh g-1 for Sb2Se3, with an improved Coulombic efficiency as well. The transient electrochemical investigations of Electrochemical Impedance Spectroscopy (EIS) and Galvanostatic intermittent titration techniques (GITT) reveal that better performance exhibited by CuSbSe2 may well be attributed to kinetics owing to enhanced diffusion coefficients in the intercalation and conversion regime.

Integrating Multiple Redox-Active Units into Conductive Covalent Organic Frameworks for High-Performance Sodium-Ion Batteries.

The rational design of porous covalent organic frameworks (COFs) with high conductivity and reversible redox activity is the key to improving their performance in sodium-ion batteries (SIBs). Herein, we report a series of COFs (FPDC-TPA-COF, FPDC-TPB-COF, and FPDC-TPT-COF) based on an organosulfur linker, (trioxocyclohexane-triylidene)tris(dithiole-diylylidene))hexabenzaldehyde (FPDC). These COFs feature two-dimensional crystalline structures, high porosity, good conductivity, and densely packed redox-active sites, making them suitable for energy storage devices. Among them, FPDC-TPT-COF demonstrates a remarkably high specific capacity of 420 mAh g-1 (0.2 A g-1), excellent cycling stability (~87 % capacity retention after 3000 cycles, 1.0 A g-1) and high rate performance (339 mAh g-1 at 2.0 A g-1) as an anode for SIBs, surpassing most reported COF-based electrodes. The superior performance is attributed to the dithiole moieties enhancing the conductivity and the presence of redox-active carbonyl, imine, and triazine sites facilitating Na storage. Furthermore, the sodiation mechanism was elucidated through in situ experiments and density functional theory (DFT) calculations. This work highlights the advantages of integrating multiple functional groups into redox-active COFs for the rational design of efficient and stable SIBs.

Valence switching of bismuth in ferricyanide as cathode materials for sodium-ion batteries

Sodium-ion batteries (SIBs) are considered potential alternatives to lithium-ion batteries, and the key to their widespread use lies in finding efficient and cost-effective cathode materials. Ferricyanides have emerged as promising candidates for SIBs cathodes due to their low cost and open channel structure allowing for favorable ion and electron transport. However, traditional ferricyanides such as Prussian blue (PB) and its analogs (PBAs) have a limited two-electron transfer capacity, which hampers their practical application. Bi-based ferricyanide materials with multiple valence states, low toxicity and abundant resources are attractive for electrochemical reactions and enable multiple electron transfers to develop high-capacity cathode materials. In this study, we synthesized a rod-like BiHCF·4H2O sample using a simple coprecipitation method. After dehydration, the rod-like BiHCF compounds with a robust framework and reduced lattice water defects demonstrated good electrochemical performance in SIBs. The rod-like BiHCF electrode exhibited a specific capacity of 221 mAh g−1 at 20 mA g−1 based on a three-electron transfer of Bi3+/Bi0. A full SIBs composed of a BiHCF cathode and Bi anode demonstrated acceptable performance, indicating potential for practical applications. This work provides valuable insights into the development of redox-active site substitution strategies for high performance positive electrode materials in SIBs.

STUDYING THE ELECTROCHEMICAL PROPERTIES OF POTASSIUM-DOPED SODIUM-MANGANESE OXIDE CATHODE MATERIALS FOR SODIUM-ION BATTERIES

The development of layered sodium manganese oxide cathode materials with high capacity and long life is one of the keys to boosting the performance of sodium-ion batteries (SIBs), but it remains a great challenge. In this work, a potassium doped P2-type sodium manganese oxide, Na0.8K0.1Mn0.9O2 (NKMO), is developed as a high-capacity and long-lasting cathode for high-performance SIBs. Sodium-potassium-manganese oxide Na0.8K0.1Mn0.9O2 was synthesized by a conventional solid-state reaction method. Crystal structure and morphology of the NKMO material were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The NKMO material was utilized to fabricate CR2032-type coin cells, and later evaluated for its electrochemical characteristics. The electrochemical characteristics of NKMO were evaluated through cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charging-discharging (GCD) at different current densities on a NEWARE battery testing system. The NKMO material had a superior initial charge and discharge capacity, approximately 130 mAh.g-1 and 125 mAh.g-1, respectively, within the voltage range of 1.5-4 V at a current density of 0.1 C. Remarkably, the capacity remained stable at 100 mAh.g-1 even after 100 cycles. These findings indicate that NKMO is a highly promising cathode material for sodium-ion batteries.

Sulfuric acid treatment to control the microcrystalline structure of starch-based hard carbon for sodium storage

By treating starch with different concentrations of sulfuric acid, we investigated the effect of cross-linked starch-based hard carbon on the performance of sodium-ion batteries (SIBs) at various concentrations. After treatment, the optimal sample exhibits a spherical microstructure, which can provide effective active sites and enhance structural stability, thereby achieving high capacity and long cycle life for SIB electrodes. In subsequent electrochemical tests, after 100 cycles at low current density of 0.1 A g−1, the capacity of H40 remains of 306 mA h g−1. And under the high current density of 1 A g−1, the capacity of H40 can still maintain of 228 mA h g−1, exhibiting a high capacity retention rate of 89 %, which is higher than other samples. This study provides a promising approach for the large-scale production of biomass-derived carbonaceous SIBs anodes.

Areal capacity balance to maximize the lifetime of layered oxide/hard carbon sodium-ion batteries

Optimizing the areal capacity balance between the negative and positive electrodes is crucial for enhancing the performance of sodium-ion batteries (SIBs). This study investigates NaNi1/3Fe1/3Mn1/3O₂ || hard carbon full cells with varying N/P ratios, employing three-electrode measurements to evaluate cycling performance and identify failure mechanisms in situ. A novel full cell design principle is proposed to determine the threshold N/P ratio for sodium plating. Electrochemical tests demonstrate that an N/P ratio slightly above the threshold value, particularly around 0.9, provides the best cycling performance within 1.5–4.1 V. The cycling degradation mechanism with different N/P ratios was also elucidated. It is due to either the PE or NE exceeding its critical window, leading to active material loss on the positive side and loss of sodium inventory on the negative side. The research further emphasizes that reasonably adjusting the working voltage window can significantly extend the battery's lifetime by suppressing degradation processes. The optimized cell, with an N/P ratio of 0.9 and operating within a 1.0–4.0 V window, demonstrates an 81 % capacity retention over 500 cycles. These findings provide a practical framework for designing high-performance SIBs that balance energy density and longevity.

Optimizing O3-type cathode materials with modified collector for sodium-ion batteries: Insights of interfacial reaction between collector and electrolyte

In order to obtain a sodium-ion battery with high energy density and good kinetic properties, high specific capacity of O3-type NaNi1/3Fe1/3Mn1/3O2 (NFM111) cathode material and high ion migration rate of NaClO4 electrolyte are selected. The cycling performance of NaNi1/3Fe1/3Mn1/3O2 is tested at 0.5 C after pre-activation at 0.1 C. During the electrochemical testing, a kind of side reaction products are found on the surface of the electrode piece. Through Scanning emission microscopy (SEM), X-ray photoelectron spectroscopy analysis (XPS) and Raman tests, side reaction products are found on the current collector with NaClO4 and Fluoroethylene carbonate (FEC). The protective layers are constructed on the surface of Al foil to effectively avoid the occurrence of side reactions. The prepared half cells have excellent stability and rate performance by the modified current collector. After 100 cycles at 0.5 C, the specific discharge capacity is 106 mA h g−1. The specific discharge capacity at 5 C is 107.2 mA h g−1. This measure provides a new idea to the NFM111 cathode materials electrochemical test and offers research basis for the design of sodium ion battery with excellent dynamic performance. Meanwhile, it also eliminates industry doubts about the performance of sodium-ion batteries.

Coal-based graphene derived from different coal ranks: exceptional sodium storage performance in sodium-ion batteries.

Coal is a premium carbon material precursor as anode materials for sodium-ion batteries (SIBs). Additionally, developing anode materials with large capacity and rapid charging performance is essential for the advancement of SIBs. Consequently, in this work, coal-based reduced graphene oxide (CrGO) was prepared as an anode materials for SIBs by a modified Hummers-high temperature thermal reduction method with different ranks of coal (coal-based graphite, CG) as a precursor. The CG prepared from higher-rank coal exhibits a higher degree of graphitization, and its graphene layers are easier to exfoliate. The unique microstructure of CrGO provides stability during the sodium storage process and exhibits fast ion capacitive adsorption behavior, enhancing reaction kinetics. CrGO, with an initial reversible capacity of up to 331 mA h g-1 at a current density of 0.03 A g-1, achieves a specific capacity of 75 mA h g-1, even at a high current density of 10 A g-1. Notably, CrGO also maintains a good specific capacity of 123 mA h g-1 after 1000 cycles at a current density of 1 A g-1, with a capacity retention rate of 91.8%. This study highlights the potential for using coal-derived materials in the development of high-performance anode materials for SIBs, promoting the green and high-value utilization of coal.

Realizing Ultrahigh Cycle Life Anode for Sodium-Ion Batteries through Heterostructure Design and Introducing Electro Active Polymer Coating.

Bi2S3 has attracted increasing attention in sodium-ion batteries (SIBs) for its high theoretical capacity and low discharge platform. However, the sodium storage performance of Bi2S3 is limited by poor electrical conductivity and volume expansion during cycling. Herein, we report a special polypyrrole (PPy)-coated MoS2/Bi2S3 (MBS@PPy) heterostructure composite obtained by hydrothermal reaction as an anode material for SIB. As a result, the MBS@PPy composites demonstrate exceptional electrochemical performance in SIB, exhibiting a high capacity of 361.1 mA h g-1 at 10 A g-1 and showcasing remarkable rate performance. Even under a high current density of 35 A g-1, the specific capacity remains stable at 280 mA h g-1 after 2,000 cycles. Furthermore, a successfully assembled Na3V2(PO4)3//MBS@PPy sodium-ion full cell can achieve an impressive specific capacity of approximately 400 mA h g-1 after 300 cycles at 0.5 A g-1. In MBS@PPy composites, the polypyridine coating not only improves the interfacial conductivity of nanorods but also effectively inhibits the agglomeration between nanorods due to large volume changes. The MoS2 heterostructure further inhibits the coarsening of the internal structure, improves electron transport and reaction kinetics, and increases the rate capability of the material. This work provides an effective strategy to develop energy storage materials with superior electrochemical properties.

Inorganic-Enriched Solid Electrolyte Interphases: A Key to Enhance Sodium-Ion Battery Cycle Stability?

The characteristics of solid electrolyte interphase (SEI) at both the cathode and anode interfaces are crucial for the performance of sodium-ion batteries (SIBs). The research demonstrates the merits of a balanced organic component, specifically the organic sodium alkyl sulfonate (ROSO2Na) featured in this work, in conjunction with the inorganic sodium fluoride (NaF), to enhance the interfacial stability. Using a customized electrolyte, it has optimized the interphase, curbing excess NaF production, and created a thin and uniform NaF/ROSO2Na-rich SEI layer. It offers exceptional protection against interface deterioration, transition metal dissolution, and concurrently ensures a consistent reduction in interfacial impedance. This creative approach results in a substantial improvement in the performance of both the Na0.9Ni0.4Fe0.2Mn0.4O2 cathode and the hard carbon anode. The cathode demonstrates remarkable average Coulombic efficiency exceeding 99.9% and a capacity retention of 81% after 500 cycles. Furthermore, the Ah-level pouch cell has shown outstanding performance with an 87% capacity retention after 400 cycles. Moving beyond the prevailing focus on inorganic-rich SEI, these results highlight the effectiveness of the customized organic-inorganic hybrid SEI formulation in improving SIB technology, offering an adaptable solution that ensures superior interfacial stability.

New anode materials for sodium-ion batteries: NixCa2-xAl-Cl LDH and CoyCa2-yAl-Cl LDH prepared from dechlorination wastes

Layered double hydroxides (LDHs) are considered promising materials in energy storage. Herein, we design a one-step ion-exchange route to prepare two new LDH-based materials, NixCa2-xAl-Cl LDH and CoyCa2-yAl-Cl LDH as anode materials for sodium-ion batteries (SIBs), using Ca2Al(OH)6Cl·2H2O (Ca2Al-Cl LDH) generated from disposing of chlorine-containing wastewater as the feed material. The high-electroactive Ni2+ and Co2+ replace a part of low-electroactive Ca2+ in Ca2Al-Cl LDH, forming NixCa2-xAl-Cl LDH and CoyCa2-yAl-Cl LDH materials with tunnel-like and defective structure, and abundant active sites. Density functional theory calculations indicate that the incorporation of Ni2+ and Co2+ effectively drives electron transfer and directly influences the charge density surrounding the active center, thereby enhancing the conductivity of NixCa2-xAl-Cl LDH and CoyCa2-yAl-Cl LDH. Ex situ XRD and XPS analyses demonstrate a redox reaction between Na+ and NixCa2-xAl-Cl LDH/CoyCa2-yAl-Cl LDH during the discharging/charging process. The NixCa2-xAl-Cl LDH and CoyCa2-yAl-Cl LDH materials exhibit excellent electrochemical performance for SIBs. Among them, Ni0.8Ca1.2Al-Cl LDH and Co0.6Ca1.4Al-Cl LDH deliver discharge capacities of 256.9 and 292.8 mAh g−1 after 200 cycles at 0.2 A g−1 and maintain the discharge capacities of 102 and 118.1 mAh g−1 after 600 cycles at 2 A g−1. This study provides a simple and low-cost method to prepare LDH-based anode materials for SIBs. It also provides a new path for the conversion of low-value dechlorination wastes into high-value-added products.

Insightful interpretation of the unique stacking faults of Na3Ni2SbO6 through cobalt doping for enhanced sodium-ion battery performance

The O3-Na3Ni2SbO6 compound, with its hexagonal honeycomb cationic ordering, is a promising sodium-ion battery (SIB) cathode due to its phase transition steps and high average voltage. In this study, various concentrations of cobalt (Co) are doped into Na3Ni2SbO6 to replace nickel (Ni), increasing disorder within the transition metal layers. Co doping introduced specific stacking faults along the c-axis direction, resulting in an ambiguous configuration of Sb/Ni(Co) within each transition metal layer, while maintaining the honeycomb order. This disorderly arrangement optimized the electronic structure and reduced the energy barrier for reactions. Na3Ni1.6Co0.4SbO6 exhibited superior performance, with a higher initial discharge capacity (137.8 mAh g-1 at 0.1 C) and better rate performance (87 mAh g-1 at 5 C) compared to Na3Ni2SbO6 (113.6 mAh g-1 at 0.1 C, 74 mAh g-1 at 5 C), including improved long-term cyclic stability. The findings demonstrate that electrochemical performance can be significantly enhanced through atomic layer stacking disorder and the Na coordination environment, which is influenced by Na ion extraction and insertion, resulting in more gradual and smaller variations in lattice parameters, electronic structure, and crystal defects. This study provides a foundation for future designs of sodium-ion battery cathode materials with improved performance.

Polydopamine derived carbon coated cobalt molybdenum layered double hydroxide as highly stable anode materials of sodium-ion battery

Two-dimensional layered double hydroxide (LDH) has promising open spaces for efficient Na+ diffusion/migration. Also, cobalt-based materials have high theoretical capacities and molybdenum incorporations can enhance electrical conductivity. Therefore, cobalt and molybdenum LDH is considered as an efficient anode material of sodium-ion battery (SIB). Nevertheless, volume expansion of LDH may limits the electrochemical performance of SIB. In this work, polydopamine (PDA) derived carbon coated cobalt molybdenum LDH (CoMoLDH) is synthesized via the hydrothermal, polymerization and carbonization processes as a novel anode material of SIB. Hydrothermal and polymerization durations are optimized to regular the morphology of CoMoLDH and achieve the suitable thickness of carbon layer. The optimal carbon coated CoMoLDH (CoMoLDH-C-PDA) anode shows a high specific capacity of 779.9 mAh/g at 0.05 A/g. After 100 cycles, the CoMoLDH-C-PDA anodes still presents a specific capacity of 310.9 mAh/g corresponding to capacity retentions of 70.0%. High specific capacity, excellent rate performance and long-term cyclic ability of CoMoLDH-C-PDA are attributed to the higher Na+ diffusion coefficient and smaller charge-transfer resistances. This study brings a blueprint for modifying novel bimetallic LDH with well-designed carbon coating, which is worthy to apply on other bimetallic LDH for enhancing rate performance and cycle life of SIB in the future.

The induced formation and regulation of closed-pore structure for biomass hard carbon as anode in sodium-ion batteries

Biomass hard carbon is regarded as an advanced anode materials for sodium ion batteries (SIBs) since it possesses balanced performance including satisfactory specific capacity, suitable operating voltage window and low cost. Although numerous instances of utilizing biomass-derived hard carbon in SIBs have been observed, the unregulated pore structure of these hard carbon materials significantly constrains the electrochemical performance of SIBs, leading to diminished initial Columbic efficiency (ICE) and plateau capacity. Herein, taking a biomass hard carbon derived from waste camellia seed shells (CSSHCs) as a template, we display a correlation between synthesis conditions and pore structure of CSSHCs. CSSHCs are synthesized via a facile route including pre‑carbonization, purifying, mechanical ball-milling and high-temperature carbonization, and it is found that adjusting the secondary calcination temperature can induce the formation of closed pore structure, which is of great benefit to increase the ICE and the plateau-capacity. Besides, it is also proved that the obtained CSSHCs anodes obey a sodium storage mechanism that can be classified as “adsorption-intercalation-pore filling”, which endows SIBs with a competitive electrochemical performance. Specifically, the obtained biomass hard carbons at 1300 °C exhibits the best electrochemical performance among these anodes with the reversible capacity of as high as 270.0 mAh g−1 and a high ICE of 80.1 %, together with an excellent cycle stability (91.0 % capacity retention after 200 cycles at 0.1C, 1C = 300 mA g−1). Therefore, this study provides a significant exploration and raw material support for the further utilization of the waste biomass and sustainable development of the anode materials for the large-scale application of SIBs.

Defect-rich hard carbon designed by heteroatom escape assists sodium storage performance for sodium-ion batteries

Sodium-ion batteries (SIBs) avoids the use of expensive cobalt element, and the abundance of sodium element is high, so it shows great application potential, and the development of sodium-ion battery materials is of great value. Biomass precursors have the advantages of low cost and widely and sufficiently distributed resources, and embody the environmental concept of waste utilization, however, the poor reversible specific capacity and initial coulombic efficiency (ICE) of pristine corn stover-derived hard carbons (CSHCs) limit their practical application value. In this paper, we propose a method to increase the reversible specific capacity of hard carbon and maintain high ICE, introduce heteroatoms into graphene-like nanosheets at low carbonization temperature, then escape heteroatoms through high pyrolysis temperature, create defects in the graphene-like carbon layer and expand the (002) layer spacing. Density functional theory (DFT) calculations show that defects are beneficial to the adsorption of Na+ on graphene-like nanosheets, and Na+ have a lower diffusion barrier between layers rich in defects and extended (002) layer spacing. Compared with the conventional low pyrolysis temperature heteroatom doping process, the present method exhibits superior ICE. In the ester-based electrolyte, the modified hard carbon (D-CSHC) exhibits a superior specific capacity of 284.5 mAh/g and an ICE of 85.9 % as compared to the pristine corn stover-derived hard carbon (233.5 mAh/g, 72.7 %). In addition, the capacity retention rate was 92.6 % after 500 turns of constant current cycles at 0.15 A/g.

Prussian White/Reduced Graphene Oxide Composite as Cathode Material to Enhance the Electrochemical Performance of Sodium-Ion Battery.

Prussian white (PW) is considered a promising cathode material for sodium-ion batteries. However, challenges, such as lattice defects and poor conductivity limit its application. Herein, the composite materials of manganese-iron based Prussian white and reduced graphene oxide (PW/rGO) were synthesized via a one-step in situ synthesis method with sodium citrate, which was employed both as a chelating agent to control the reaction rate during the coprecipitation process of PW synthesis and as a reducing agent for GO. The low precipitation speed helps minimize lattice defects, while rGO enhances electrical conductivity. Furthermore, the one-step in situ synthesis method is simpler and more efficient than the traditional synthesis method. Compared with pure PW, the PW/rGO composites exhibit significantly improved electrochemical properties. Cycling performance tests indicated that the PW/rGO-10 sample exhibited the highest initial discharge capacity and the best cyclic stability. The PW/rGO-10 has an initial discharge capacity of 128 mAh g-1 at 0.1 C (1 C = 170 mA g-1), and retains 49.53% capacity retention after 100 cycles, while the PW only delivers 112 mAh g-1 with a capacity retention of 17.79% after 100 cycles. Moreover, PW/rGO-10 also shows better rate performance and higher sodium ion diffusion coefficient (DNa+) than the PW sample. Therefore, the incorporation of rGO not only enhances the electrical conductivity but also promotes the rapid diffusion of sodium ions, effectively improving the electrochemical performance of the composite as a cathode material for sodium-ion batteries.