Application In Sodium-ion Batteries Research Articles

Na-deficient P2-type layered oxide cathodes for practical sodium-ion batteries

Sodium-ion batteries (SIBs) have attracted enormous attention as candidates in stationary energy storage systems, because of the decent electrochemical performance based on cheap and abundant Na-ion intercalation chemistry. Layered oxides, the workhorses of modern lithium-ion batteries, have regained interest for replicating their success in enabling SIBs. A unique feature of sodium layered oxides is their ability to crystallize into a thermodynamically stable P2-type layered structure with under-stoichiometric Na content. This structure provides highly open trigonal prismatic environments for Na ions, permitting high Na+ mobility and excellent structural stability. This review delves into the intrinsic characteristics and key challenges faced by P2-type cathodes and then comprehensively summarizes the up-to-date advances in modification strategies from compositional design, elemental doping, phase mixing, morphological control, and surface modification to sodium compensation. The updated understanding presented in this review is anticipated to guide and expedite the development of P2-type layered oxide cathodes for practical SIB applications.

Phosphorus‑carbon based hybrid electrodes for sodium ion batteries

In this study, commercial phosphorus powders were first subjected to mechanical ball-milling at varying times and reinforced with graphene oxide and multiwall carbon nanotubes to improve their electrochemical performances. All these processes were carried out by ball milling method to provide mechanical alloying of phosphorus. Subsequently, the crystallinity of the samples was analyzed by X-ray diffraction method, while the morphology of the samples was examined by field emission scanning electron microscopy. The main obstacles that inhibit the reversibility and the cyclic stability of red phosphorus are low electronic conductivity and huge volumetric expansion. Reinforcing amorphized phosphorous with multi-walled carbon nanotube and graphene oxide composites has presented similar initial capacity of 2100 mAh g−1. In addition, reversible capacity of multi-walled carbon nanotube and graphene oxide reinforced samples presented 370 mAh g−1 and 507 mAh g−1 after 250 cycles, respectively. Our results have shown that graphene oxide reinforced composites could be an alternative electrode material for sodium ion battery applications.

Scalable Synthesis of Layered Bismuth Germanate (Bi12GeO20) for Supercapacitors and Sodium ion Battery Applications

Scalable Synthesis of Layered Bismuth Germanate (Bi12GeO20) for Supercapacitors and Sodium ion Battery Applications

Investigating the effect of calcination temperature on the electrochemical properties of Na4MnV(PO4)3/NC@CNTs cathode materials for sodium ion batteries

Manganese-based NASICON-type Na4MnV(PO4)3 (NVMP) is used as an alternative material to the cathode materials (Na3V2(PO4)3) for sodium-ion battery (SIBs). By selecting the cheap and easily available and environmentally non-polluting Mn element to replace part of the highly toxic and expensive V element, it has the advantages of higher voltage platform, lower cost and weaker toxicity. However, the low intrinsic conductivity and poor cycling stability of NVMP severely limit its application in SIBs. In this paper, N-doped double carbon layer-coated NVMP composites (NVMP/NC@CNTs) are prepared by adding additional urea as a nitrogen source and CNTs as a carbon source using a simple and feasible sol-gel synthesis method, which improves their electronic conductivity and structural stability. On this basis, the effects of calcination temperature on the lattice structure, specific surface area, carbon disorder, Na+ diffusion coefficient (DNa+) and electrochemical properties of NVMP/NC@CNTs composites are mainly investigated. The results show that the optimal annealing temperature is 650 °C, and the NVMP/NC@CNTs material has the highest discharge capacity (105.6 mAh g−1 at 0.1C), the best rate performance (75.7 mAh g−1 at 5C), and the most stable cycling stability (79.4 %/89.3 % for 500 cycles at 1C / 5C, respectively). Even at high rate of 10C, an impressive cycling stability (77.5 % capacity retention over 1500 cycles). The sodium storage mechanism, electrochemical performance and pseudo-capacitance contribution of NVMP/NC@CNTs-650 are further investigated by kinetic analysis, GITT test, ex-situ XPS, XRD and EIS characterization. Finally, the assembled NVMP/NC@CNTs-650 || hard carbon (HC) full cell manifests a high capacity of 87.2 mAh g−1 with capacity retention of 92.5 % over 50 cycles at 1C. The results reveal that the appropriate annealing temperature can help to prepare electrochemically excellent and structurally stable NVMP composites, while the co-modification of N-doped dual-nanocarbon can produce a large number of defects and active sites, which is expected to facilitate the commercialization of SIBs.

Bi Nanospheres Embedded in N-Doped Carbon Nanowires Facilitate Ultrafast and Ultrastable Sodium Storage.

Sodium ion batteries (SIBs) are considered as the ideal candidates for the next generation of electrochemical energy storage devices. The major challenges of anode lie in poor cycling stability and the sluggish kinetics attributed to the inherent large Na+ size. In this work, Bi nanosphere encapsulated in N-doped carbon nanowires (Bi@N-C) is assembled by facile electrospinning and carbonization. N-doped carbon mitigates the structure stress/strain during alloying/dealloying, optimizes the ionic/electronic diffusion, and provides fast electron transfer and structural stability. Due to the excellent structure, Bi@N-C shows excellent Na storage performance in SIBs in terms of good cycling stability and rate capacity in half cells and full cells. The fundamental mechanism of the outstanding electrochemical performance of Bi@N-C has been demonstrated through synchrotron in-situ XRD, atomic force microscopy, ex-situ scanning electron microscopy (SEM) and density functional theory (DFT) calculation. Importantly, a deeper understanding of the underlying reasons of the performance improvement is elucidated, which is vital for providing the theoretical basis for application of SIBs.

Ti-doped O3-NaNi0.5Mn0.5O2 as high-performance cathode materials for sodium-ion batteries

With favorable electrochemical activity, NaNi0.5Mn0.5O2(NNMO) has been a key cathode material in sodium-ion batteries. However, the phase-transition irreversible and kinetics sluggish issues in NaNi0.5Mn0.5O2 greatly limit its application in sodium-ion batteries. Here, various Ti-doped O3-NaNi0.5Mn0.5-xTixO2 cathode materials were fabricated via solid-phase method. The extra Ti-doping treatment effectively stabilized the transition layer of metal and enlarged the Na layer spacing, as well as suppressed the Na+/vacancy ordering. In particular, the obtained O3-NaNi0.5Mn0.46Ti0.04O2 (NNMOTi-4) exhibits initial reversible capacity of 108.6 mAh g−1 at 0.1C and remarkable 65.2% capacity retention after 100 cycles at 1C. Accordingly, this work provides a facile Ti-doping strategy to regulate the structure and electrochemical performance of layered NaxTMO2 for sodium-ion batteries.

Insight into the effect of structural differences among pitch fractions on sodium storage performance of pitch-derived hard carbons

Pitch is an excellent precursor of hard carbons (HCs) with low-cost and high carbon content, enabling its commercial-scale application in sodium-ion batteries. Pre-oxidation is the key to obtaining pitch-derived HCs with disordered microstructures. However, pitch is a mixture of fractions with different molecular weights and structures. With the introduction of oxygen, the cross-linked structure established by each fraction could be different, the effect of which on the microstructure and sodium storage performance of HCs remains unclear. Here, we separate pitch into three fractions and further pre-oxidize and carbonize to produce HCs, in order to systematically investigate the effects of structural differences among pitch fractions on the cross-linking mechanism and microstructure of as-obtained HCs. It is found that tetrahydrofuran-insoluble (THFI) enables the enrichment of polar oxygen functional groups, thus enhancing its oxidative activity to obtain more oxygen for the construction of abundant three-dimensional cross-linked structure. It is conducive to preventing the rearrangement of carbon layers and promoting the development of micropores during high-temperature carbonization process, which facilitates the storage of sodium ions in the low-voltage plateau region. The resulting hard carbon (THFI-1400) has significantly improved overall sodium storage performances. This work provides a new strategy to prepare low-cost and high-performance HCs.

In-situ pre-sodiation of Prussian blue for the construction of high-performance sodium-ion batteries

Prussian blue and its analogs have attracted increasing attention owing to their stable structure and low cost, especially in the field of sodium-ion batteries. However, the insufficient sodium and high contents of water in the structure greatly hinder their practical applications. Herein, an in-situ pre-sodiation strategy is conducted to realize a one-step transformation of sodium-poor Prussian blue (NP-PB) to sodium-rich Prussian blue (NR-PB) without the introduction of other impurities. The introduced sodium ions take the place of coordination water, resulting in richer sodium ion transport channels and higher structural stability. Thanks to the high sodium content and low water content in the structure, the as prepared NR-PB presents a significantly higher initial coulombic efficiency of 95.18% compared to that of NP-PB (41.93%). When coupled with hard carbon (HC), the NP-PB//HC cell exhibits an ultra-high capacity retention of 93.71% after 300 cycles at a current density of 200 mAh/g. Our work provides guidance for the in-situ transformation of sodium-poor Prussian blue into sodium-rich Prussian blue, which is of great importance for the practical applications of sodium ion batteries.

Compositing pine pollen derived carbon matrix with Na4FeV(PO4)3 nanoparticle for cost-effective sodium-ion batteries cathode

Na super-ion conductor type material Na3V2(PO4)3 has been widely researched as the cathode of sodium-ion batteries (SIBs) in recent years, but the unsatisfying cost of Na3V2(PO4)3 impedes its wide application in SIBs. In this study, iron element is used to replace part of vanadium in Na3V2(PO4)3 to reduce its expense, and pine pollen is applied for the first time as a very effective carbon source to improve the performance of Na4FeV(PO4)3. The fabricated composite material achieves a capacity of 105 mA h g−1 under 0.2 C and fascinating cycling stability over 94 % under 2 C for 500 cycles and 98 % under 10 C for 1000 cycles. The excellent cycle performance is caused by the involvement of pine pollen that acts as a carbon matrix to enhance the electron conductivity and block the agglomeration of active material effectively, thus the well-dispersed nano sized Na4FeV(PO4)3 shortens the diffusion path of sodium ion and gains a remarkable rate capability. Moreover, the distinguished reversibility during the charge and discharge procedures is ascribed also to the robust structure of Na4FeV(PO4)3. This work provides an efficient route to realize the economic cathode material of SIBs with good performance.

Enhanced redox kinetics in hierarchical tubular FeSe2 by incorporating Se quantum dots towards high-performance sodium-ion batteries

Metal selenides have emerged as promising Na-storage anode materials owing to their substantial theoretical capacity and high cost-effectiveness. However, the application of metal selenides is hindered by inferior electronic conductivity, huge volume variation, and sluggish kinetics of ionic migration. In response to these challenges, herein, a hierarchical hollow tube consisting of FeSe2 nanosheets and Se quantum dots anchored within a carbon skeleton (HT-FeSe2/Se/C) is strategically engineered and synthesized. The most remarkable feature of HT-FeSe2/Se/C is the introduction of Se quantum dots, which could lead to high electron density near the Fermi level and significantly enhance the overall charge transfer capability of the electrode. Moreover, the distinctive hollow tubular structure enveloped by the carbon skeleton endows the HT-FeSe2/Se/C anode with robust structural stability and fast surface-controlled Na-storage kinetics. Consequently, the as-synthesized HT-FeSe2/Se/C demonstrates a reversible capacity of 253.5 mAh/g at a current density of 5 A/g and a high specific capacity of 343.9 mAh/g at 1 A/g after 100 cycles in sodium-ion batteries (SIBs). Furthermore, a full cell is assembled with HT-FeSe2/Se/C as the anode, and a vanadium-based cathode (Na3V2(PO4)2O2F), showcasing a high specific capacity of 118.1 mAh/g at 2 A/g. The excellent performance of HT-FeSe2/Se/C may hint at future material design strategies and advance the development and application of SIBs.

Iron‐Based Sulfate for Sodium‐Ion Batteries: Past, Present, and Future

Sodium‐ion batteries (SIBs) are crucial energy equipment that sustain low cost and better environmental benefit. Nevertheless, the practical energy density of SIBs is limited by cathode material. Over last decades, the iron‐based sulfate (IBS) has been extensively studied owing to its numerous advantages, including a large theoretical specific energy (over 100 Wh kg−1), high working potential (above 3.4 V), low cost, good structural stability, and environmental friendliness. Nevertheless, the application of IBS in SIBs is limited by its unsuitable electrolyte and low electronic/ionic conductivity. This review summarizes recently developed results on IBS materials for SIBs, ranging from the phase diagram–composition structure–electrochemical performance to modification research. A generalized summary of the future prospects of IBS‐based materials is also provided, with the hope of inspiring further advances in their application in SIBs.

Sb-Doped Biphasic P2/O3-Type Mn-Rich Layered Oxide Cathode Material for High-Performance Sodium-Ion Batteries.

Mn-rich P2-type layered oxide cathode materials suffer from severe capacity loss caused by detrimental phase transition and transition metal dissolution, making their implementation difficult in large-scale sodium-ion battery applications. Herein, we introduced a high-valent Sb5+ substitution, leading to a biphasic P2/O3 cathode that suppresses the P2-O2 phase transformation in the high-voltage condition attributed to the stronger Sb-O covalency that introduces extra electrons to the O atom, reducing oxygen loss from the lattices and improving structural stability, as confirmed by first-principle calculations. Besides, the enhanced Na+ diffusion kinetics and thermodynamics in the modified sample are associated with the enlarged lattice parameters. As a result, the proposed cathode delivers a discharge capacity of 142.6 mAh g-1 at 0.1C between 1.5 and 4.3 V and excellent performance at a high mass loading of 8 mg cm3 with a specific capacity of 131 mAh g-1 at 0.2C. Furthermore, it also possesses remarkable rate capability (90.3 mAh g-1 at 5C), specifying its practicality in high-energy-density sodium-ion batteries. Hence, this work provides insights into incorporating high-valent dopants for high-performance Mn-rich cathodes.

Density functional theory analysis of Na4Mn4Ti5O18 for sodium ion battery electrode

Density functional theory study has been performed on Na4Mn4Ti5O18 to evaluate its application feasibility as an electrode in Na ion battery. Two types of void in the structure of Na4Mn4Ti5O18, viz., Z shaped tunnel and polyhedral pentagonal void, has been observed that act as guest sites for reversible migration of Na+ ions. It is also noted that electrochemically active sites are placed in Z shaped tunnel that act as host for Na+ during anodic response while it acts as the Na+ donor during cathodic response. The Mn atom, located in the Z-shape tunnel, acts as redox active site for both cathodic and anodic response via formation of redox couple Mn+3/Mn+4 and Mn+3/Mn+2 respectively. On the other hand, Mn atom present at square pyramidal site remains inert during charge–discharge process. The redox action in Na4Mn4Ti5O18, occurring due to intercalation and de-intercalation of 2Na+ ions per formula unit, has been noted to exhibit voltage ∼2.63 V and 3.82 V respectively. The theoretical capacity ∼128 mAhg−1 has been estimated corresponding to migration of 2Na+ in Na4Mn4Ti5O18 structure. The present simulation study indicates the possibility of electrode action in Na4Mn4Ti5O18 for sodium ion battery application.

Progress and Prospect of Bimetallic Oxides for Sodium-Ion Batteries: Synthesis, Mechanism, and Optimization Strategy.

Sodium-ion batteries (SIBs) are considered as an alternative to and even replacement of lithium-ion batteries in the near future in order to address the energy crisis and scarcity of lithium resources due to the wide distribution and abundance of sodium resources on the earth. The exploration and development of high-performance anode materials are critical to the practical applications of advanced SIBs. Among various anode materials, bimetallic oxides (BMOs) have attracted special research attention because of their abundance, easy access, rich redox reactions, enhanced capacity and satisfactory cycling stability. Although many BMO anode materials have been reported as anode materials in SIBs, very limited studies summarized the progress and prospect of BMOs in practical applications of SIBs. In this review, recent progress and challenges of BMO anode materials for SIBs have been comprehensively summarized and discussed. First, the preparation methods and sodium storage mechanisms of BMOs are discussed. Then, the challenges, optimization strategies, and sodium storage performance of BMO anode materials have been reviewed and summarized. Finally, the prospects and future research directions of BMOs in SIBs have been proposed. This review aims to provide insight into the efficient design and optimization of BMO anode materials for high-performance SIBs.

Dual Design on Hierarchically Hollow MoTe2/C with Ion/Electron Channel Engineering for High-Performance Sodium Storage.

Transition-metal tellurides have been investigated as novel anode materials for application in sodium-ion batteries (SIBs) due to their rich active sites and unique and controllable layered nanostructures. However, the weak structural strength and inferior intercalation/deintercalation kinetics inhibit the development of transition-metal tellurides. In this work, MoTe2/C composites with two different hollow nanostructures are designed and prepared. By adjustment of the precursor structure, MoTe2/C-2 exhibits superior sodium-storage performance because of its uniquely hollow nanostructure with self-assembled 2D flexible nanosheets grown on the external surface. MoTe2/C-2 delivers a higher specific capacity (276 mAh g-1 at 0.1 A g-1 after 300 cycles), much more than MoTe2/C-1 (201 mAh g-1 at 0.1 A g-1 after 300 cycles), and exhibits a long-time cycling performance (131 mAh g-1 at 1 A g-1 after 2000 cycles). The excellent sodium-storage performance derived from the rational structure design is beneficial for shortening the ion paths, facilitating the sodiation/desodiation process, and reinforcing the intrinsic structural stability, thus boosting the reaction kinetics and prolonging the cycling life. Meanwhile, the assembled full-cell maintains 101 mAh g-1 at 0.1 A g-1 after 50 cycles and lights an electric watch. The findings provide several new views for preparation of more transition-metal tellurides with multi-ion/electron migration channel engineering.

Tin-antimony/carbon composite porous fibers: electrospinning synthesis and application in sodium-ion batteries

In this work, tin-antimony/carbon composites porous fibers were successfully synthesized by an electrospinning method combined with two-step heat treatment processes, in which SnCl2 and SbCl3 were used as tin and antimony sources, and polyacrylonitrile (PAN) and polymethyl methacrylate (PMMA) were used as binders and pore-forming agents. The as-synthesized tin-antimony/carbon composites were systematically characterized by x-ray Diffraction (XRD), Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), Energy-Dispersive Spectrometer (EDS), x-ray Photoelectron Spectroscopy (XPS), and Thermogravimetric Analysis-Differential Scanning Calorimetry (TG-DSC). The results indicate that the composite material consists of one-dimensional nitrogen-doped carbon porous fibers as the main matrix, with a three-dimensional network structure in which Sn, SnO2, and SnSb particles are encapsulated. Furthermore, the tin-antimony/carbon composites porous fibers were utilized as self-supported negative electrode for sodium-ion batteries. The results showed that the SNbM-2 sample electrode calcined at 800 °C demonstrated the best cycling stability and rate capability among all the sample electrodes, with a discharge capacity of 319.5 mAh·g−1 maintained after 100 cycles at a current density of 0.1 A·g−1. The excellent electrochemical performance of the SNbM-2 sample electrode is benefited from its unique porous structure and the carbon fiber network structure encapsulating Sn, SnO2, and SnSb particles, which could effectively shorten the Na+ ion transport distance and mitigate electrode volume expansion.

Mechanically Robust Self-Organized Crack-Free Nanocellular Graphene with Outstanding Electrochemical Properties in Sodium Ion Battery.

Crack-free nanocellular graphenes are attractive materials with extraordinary mechanical and electrochemical properties, but their homogeneous synthesis on the centimeter scale is challenging. Here, a strong nanocellular graphene film achieved by the self-organization of carbon atoms using liquid metal dealloying and employing a defect-free amorphous precursor is reported. This study demonstrates that a Bi melt strongly catalyzes the self-structuring of graphene layers at low processing temperatures. The robust nanoarchitectured graphene displays a high-genus seamless framework and exhibits remarkable tensile strength (34.8MPa) and high electrical conductivity (1.6 × 104 S m-1). This unique material has excellent potential for flexible and high-rate sodium-ion battery applications.

Interface engineering of metal sulfides-based composites enables high-performance anode materials for sodium-ion batteries

Metal sulfides (MSs) have attracted much attention as anode materials for sodium-ion batteries (SIBs) due to their high sodium storage capacity. However, the unsatisfactory electrochemical performance induced by the huge volume change and sluggish kinetics hampered the practical application of SIBs. Herein, guided by the heterostructure interface engineering, novel multicomponent metal sulfide-based anodes, including SnS, FeS, and Fe3N embedded in N-doped carbon nanosheets (SnS/FeS/Fe3N/NC NSs), have been synthesized for high-performance SIBs. The as-prepared SnS/FeS/Fe3N/NC NSs with abundant heterointerfaces and high conductivity of N-doped carbon nanosheet matrix can shorten the Na+ diffusion path and promote reaction kinetics during the sodiation/desodiation process. Moreover, the presence of Fe3N can promote the reversible conversion of SnS and FeS during the cycling process. As a consequence, when evaluated as anode materials for SIBs, the SnS/FeS/Fe3N/NC NSs can maintain a high sodium storage capacity of 473.6 mAh g-1 after 600 cycles at 2.0 A g-1 and can still provide a high reversible capacity of 537.4 mAh g-1 even at 5.0 A g-1 This discovery offers a novel strategy for constructing metal sulfide-based anode materials for high-performance SIBs.

Architectural design of anode materials for superior alkali-ion (Li/Na/K) batteries storage

Developing high-performance anode materials remains a significant challenge for clean energy storage systems. Herein, we investigated the (MXene/MoSe2@C) heterostructure hybrid nanostructure as a superior anode material for application in lithium, sodium, and potassium ion batteries (LIBs, SIBs, and PIBs). Moreover, the anode structure’s stability was examined via the open-source Large-scale atomic/molecular massively Parallel Simulator code. Our results indicated that the migration of SIBs toward the anode material is significantly greater than other ions during charge and discharge cycles. Therefore, SIBs systems can be competitive with PIBs and LIBs systems. In addition, the average values of the potential energies for the anode materials/ions complexes are about ~ − 713.65, ~ − 2030.41, and ~ − 912.36 kcal mol−1 in systems LIBs, SIBs, and PIBs, respectively. This study provides a rational design strategy to develop high-performance anode materials in SIBs/PIBs/LIBs systems, which can be developed for other transition metal chalcogenide-based composites as a superior anode of alkali metal ion battery storage systems.

Structurally Stable, Low H2O Prussian Blue Analogs toward High Performance Sodium Storage

AbstractPrussian blue analogues (PBAs) are recognized as promising cathode materials for sodium‐ion batteries (SIBs) due to their facile synthesis, low‐cost, high capacity, and environmental friendliness. However, high water content (>10 wt%) in the framework and unsatisfactory structural stability of PBAs are still the bottlenecks for industrial applications. Herein, interstitial K‐doping is employed to minimize the interstitial water and enhance the structural stability of Na2‐xFeMn[Fe(CN)6] (FeMnPBA), thereby boosting the sodium storage performance. The 3% K‐doping (K‐FeMnPBA3) demonstrates a much‐reduced water content of 6.9%, accompanied by a notably enhanced capacity of 139.1 mAh g−1 at 100 mA g−1 and a remarkable capacity retention of 77.1% after 700 cycles. Furthermore, the K‐FeMnPBA3/hard carbon (HC) pouch cell achieves a stable cyclability with 82.6% capacity retention after 600 cycles. This research offers valuable insights into low‐water PBAs for practical applications in SIBs.