Practical Application Of Sodium-ion Batteries Research Articles

Charge-Compensation-Driven Failure Mechanism of Ni Redox in Fe-Rich Ni/Fe/Mn-Based O3-Type Layered Oxide Sodium-Ion Cathodes.

For cathode materials of sodium-ion batteries, O3-type Ni/Fe/Mn-based (Na-NFM) layered oxides have garnered extensive attention because of high economic viability, environmental friendliness, and the potential for high energy density. Among them, Fe-rich compositions exhibit higher initial charge capacity and lower bill-of-material costs, while they fade rapidly and exhibit low initial coulombic efficiency, hindering their commercialization prospects. In this work, we investigate the failure of Fe-rich Na-NFM materials through X-ray absorption spectroscopy methods. The results reveal a combined failure mechanism that encompasses not only the conventional theory of Fe migration but also an abnormal Ni-redox deterioration, which has not yet been reported. More factors related to the failure of Fe-rich Na-NFM layered oxides are discussed in detail. These findings are expected to inspire targeted research efforts toward Fe-rich Na-NFM materials, thereby accelerating the practical application of sodium-ion batteries.

Advances and Challenges of Porous Structure on Solid–Liquid Interfaces in Polyanionic Sodium‐Ion Batteries

AbstractThe sodium‐ion batteries (SIBs) are expected to be the substitute for lithium‐ion batteries (LIBs) because of their low cost, high abundance, and similar working mechanism. Among them, polyanion‐type electrodes show great application prospects due to their superior ion diffusion channels and structural stability. However, there are still many scientific issues that need to be thoroughly investigated, especially the formation mechanism, structural stability, and interface impedance of solid–liquid interfaces. Therefore, it is of great significance to systematically study the mechanism of interface reaction and the electrochemical behavior, to promote the further practical application of SIBs. Fortunately, the polyanionic electrodes can effectively improve the transport dynamics and the interfacial stability of the solid–liquid interfaces through constructing the porous structure, surface modification, and electrolyte strategies, thus improving the cycle and rate performance. This review discusses the characteristics and formation mechanisms of electrode/electrolyte interface (EEI), as well as their electrochemical behavior in porous structures with different dimensions. Furthermore, this review covers the application of porous materials in improving transport kinetics and EEI. In particular, it highlights the various strategies employed to comprehend the interplay among structure, chemistry, preparation methods, and the mechanisms of porous electrodes that ultimately affect the electrochemical properties of SIBs.

Off-Stoichiometry of Sodium Iron Pyrophosphate as Cathode Materials for Sodium-Ion Batteries with Superior Cycling Stability.

As one of the important devices for large-scale electrochemical energy storage, sodium-ion batteries have received much attention due to the abundant resources of raw materials. However, whether it is a base station power source, an energy storage power station, or a start-stop power supply, long energy cycle life (more than 5000 cycles), high stability, and safety performance are application prerequisites. Regrettably, currently, few sodium-ion batteries can meet this requirement, mainly due to shortcomings in positive electrode performance. We report a sufficiently stable sodium-ion battery cathode material, Na2Fe0.95P2O7, that retains 97.5% capacity after 5000 charge/discharge cycles. The use of nonstoichiometry in the lattice enables simultaneous modification of the crystal and electronic structure, promoting Na2Fe0.95P2O7 to be extremely stable while still being able to achieve a capacity of 92 mAh g-1 and stable cycling at high temperatures up to 60 °C. Our results confirm the positive effect of nonstoichiometric ratios on the performance of Na2Fe0.95P2O7 and provide a reliable idea to promote the practical application of sodium-ion batteries.

Ultrafast synthesis of hard carbon for high-rate and low-temperature sodium-ion storage through flash Joule heating

Developing effective strategies to promote the sodium-ion storage performance of hard carbon anodes is essential for its practical application in sodium-ion batteries. The carbonization process plays a crucial role in regulating the microstructure of hard carbon. Conventional carbonization methods of slow-heating have hit a bottleneck in structural controls of hard carbon materials. Herein, hard carbon with high-rate and low-temperature sodium storage capability is ultrafast synthesized by flash Joule heating. Compared to the hard carbon synthesized by conventional slow-heating, the hard carbon synthesized by flash Joule heating has smaller particle size, larger interlayer spacing, and larger closed-pores leading to superior performance. This work provides a simple and effective method of boosting sodium-ion storage performance for hard carbon materials.

Pyridinic N‐Dominated Hard Carbon with Accessible Carbonyl Groups Enabling 98% Initial Coulombic Efficiency for Sodium‐Ion Batteries

AbstractHard carbon (HC) has been widely regarded as the most promising anode material for sodium‐ion batteries (SIBs) due to its decent capacity and low cost. However, the poor initial Coulombic efficiency (ICE) of HC seriously hinders its practical application in SIBs. Herein, pyridinic N‐doped hard carbon polyhedra with easily accessible carbonyl groups and in situ coupled carbon nanotubes are rationally synthesized via a facile pretreated zeolitic imidazolate framework (ZIFs)‐carbonization strategy. The comprehensive ex/in situ techniques combined with theoretical calculations reveal that the synergy of pyridinic‐N and carbonyl groups promoted by the pretreatment and carbonization process would not only optimize the Na+ adsorption energy but also accelerate the desorption of Na+, significantly suppressing the irreversible capacity loss. As a result, the as‐synthesized hard carbon polyhedra as an anode can deliver an unprecedented high ICE of 98% with a large reversible capacity of 389.4 mAh g−1 at 0.03 A g−1. This work may provide an effective strategy for the structural design of HC with high ICE.

Designing Advanced Electrolytes for High-Safety and Long-Lifetime Sodium-Ion Batteries via Anion-Cation Interaction Modulation.

Safety hazards caused by flammable electrolytes have been major obstacles to the practical application of sodium-ion batteries (SIBs). The adoption of nonflammable all-phosphate electrolytes can effectively improve the safety of SIBs; however, traditional low-concentration phosphate electrolytes are not compatible with carbon-based anodes. Herein, we report an anion-cation interaction modulation strategy to design low-concentration phosphate electrolytes with superior physicochemical properties. Tris(2,2,2-trifluoroethyl) phosphate (TFEP) is introduced as a cosolvent to regulate the ion-solvent-coordinated (ISC) structure through enhancing the anion-cation interactions, forming the stable anion-induced ISC (AI-ISC) structure, even at a low salt concentration (1.22 M). Through spectroscopy analyses and theoretical calculations, we reveal the underlying mechanism responsible for the stabilization of these electrolytes. Impressively, both the hard carbon (HC) anode and Na4Fe2.91(PO4)2(P2O7) (NFPP) cathode work well with the developed electrolytes. The designed phosphate electrolyte enables Ah-level HC//NFPP pouch cells with an average Coulombic efficiency (CE) of over 99.9% and a capacity retention of 84.5% after 2000 cycles. In addition, the pouch cells can operate in a wide temperature range (-20 to 60 °C) and successfully pass rigorous safety testing. This work provides new insight into the design of the electrochemically compatibility electrolyte for high-safety and long-lifetime SIBs.

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.

Hard carbon from a sugar derivative for next-generation sodium-ion batteries.

Sodium-ion batteries have emerged as a promising secondary battery system due to the abundance of sodium resources. One of the boosters for accelerating the practical application of sodium-ion batteries is the innovation in anode materials. This study focuses on developing a high-performance hard carbon anode material derived from hydroxymethylfurfural, produced from carbohydrates, using a straightforward thermal condensation method. The process results in a unique pseudo-graphitic material with abundant microporosity. Electrochemical evaluations demonstrate excellent sodium storage performance by maintaining the plateau capacity even at higher current densities. This translates to a promising energy density when coupled with the cathode material. However, we also discuss the influence of electrolyte composition on the performance of the hydroxymethylfurfural-derived hard carbon, emphasizing the critical role of electrolyte optimization for the development of efficient and sustainable carbonaceous anode materials for next-generation sodium-based batteries.

Micro-stress pump with variation of stress to boost the ion transport for high-performance sodium-ion batteries

The sluggish kinetics limits the practical application of sodium-ion batteries (SIBs), the innovative strategy and design of materials with fast reaction kinetics are important for SIBs. To solve the issues,...

Elevating the Practical Application of Sodium-Ion Batteries through Advanced Characterization Studies on Cathodes

Sodium-ion batteries (SIBs) have emerged as promising alternatives to their lithium-ion counterparts due to the abundance of sodium resources and their potential for cost-effective energy storage solutions. The chemistry for SIBs has been investigated since the 1980s, but it went through a slow research and development process. Recently, there has been an acceleration in technology maturation due to a supply chain crisis originating from unequal resource distribution and sustainability and safety concerns regarding lithium-ion batteries. However, the practical application of SIBs has been hindered primarily by challenges related to cathode materials, specifically, surface and structural stabilities in different conditions. Through the integration of advanced techniques such as in situ spectroscopy, operando diffraction, and high-resolution microscopy, a comprehensive understanding of the cathode’s dynamic behavior and degradation mechanisms can be achieved. The identified structural modifications, phase transitions, and degradation pathways offer critical insights into the design of robust cathode materials with prolonged cycling stability, fast charging capability, high energy density, great low-temperature performance, and safety. This review underscores the pivotal role of cutting-edge characterization techniques in guiding the development of high-performance sodium-ion batteries, thereby fostering the realization of sustainable and efficient energy storage solutions for diverse technological applications.

Designing hollow Ti3C2@TiSe2 composites for long cycle life of sodium-ion storage

The construction of an anode material with high electrical conductivity and long cycle stability was essential for the practical application of Sodium-ion batteries (SIBs). Hollow Ti3C2@TiSe2 composites were successfully synthesized using in situ selenization methods from MXene-derived materials. The composites obtained in this study exhibited an impressive reversible capacity, attaining a specific capacity of 561 mAh g−1 when tested at a current density of 0.1 A g−1.The specific capacity remained stable at 201 mAh g−1 through 12,000 cycles at a high current density of 10 A g−1. When utilizing Na3V2(PO4)3@C (NVP@C) as the cathode in a full cell, it demonstrated a sustained specific capacity of 138 mAh g−1 over 50 cycles at a current density of 100 mA g−1. Additionally, a capacity of 98 mAh g−1 was maintained over 500 charge-discharge cycles at a higher current density of 1000 mA g−1. The reaction mechanism of Na+ was confirmed through reaction kinetics and ex-situ XRD test. This study demonstrated that the special hollow structure comprised of Ti3C2 and TiSe2 enhanced the material's structural stability as well as the surface activity.

Two-dimensional layered In2P3S9: A novel superior anode material for sodium-ion batteries

Developing reliable and efficient anode materials is essential for the successfully practical application of sodium-ion batteries. Herein, employing a straightforward and rapid chemical vapor deposition technique, two-dimensional layered ternary indium phosphorus sulfide (In2P3S9) nanosheets are prepared. The layered structure and ternary composition of the In2P3S9 electrode result in impressive electrochemical performance, including a high reversible capacity of 704 mA h g−1 at 0.1 A g−1, an outstanding rate capability with 425 mA h g−1 at 5 A g−1, and an exceptional cycling stability with a capacity retention of 88% after 350 cycles at 1 A g−1. Furthermore, sodium-ion full cell also affords a high capacity of 308 and 114 mA h g−1 at 0.1 and 5 A g−1. Ex-situ X-ray diffraction and ex-situ high-resolution transmission electron microscopy tests are conducted to investigate the underlying Na-storage mechanism of In2P3S9. The results reveal that during the first cycle, the P–S bond is broken to form the elemental P and In2S3, collectively contributing to a remarkably high reversible specific capacity. The excellent electrochemical energy storage results corroborate the practical application potential of In2P3S9 for sodium-ion batteries.

An effective strategy to prepare non-graphitic carbon with increased pseudo-graphitic content for sodium-ion battery anode with enhanced plateau capacity

The practical application of sodium-ion batteries is mainly hindered by relatively low energy density, which can be effectively overcome by increasing the pseudo-graphitic content in non-graphitic carbon (NGC) anodes. Herein, a simple and efficient strategy was reported to promote the growth of pseudo-graphitic domains in NGC thanks to the synergistic effect of pre-carbonization and NaOH etching using semi-coke as precursor. Based on pre-carbonization at 800 °C and NaOH etching with NaOH/carbon ratio of 0.5 at 600 °C, the resultant NGC (FC-800–0.5–600) exhibits a 13 % increase in percentage of pseudo-graphitic structure meanwhile 14 % decrease for graphite-like structure, but similar content of highly disordered structure compared with its counterpart. Notably, although similar in sloping capacity, FC-800–0.5–600 possesses much higher plateau capacity (<0.1 V) of 218.6 mAh g−1 than its counterpart (174.9 mAh g−1), which is attributed to the enhanced “interlayer intercalation” effect related with pseudo-graphitic structure. Thus, FC-800–0.5–600 can deliver an impressive reversible capacity of 326.8 mAh g−1 at 20 mA g−1, together with a considerable ICE of 84.7 %. This work proposed an effective strategy to increase pseudo-graphitic structure content in NGC, providing a rational guide for designing high-performance anodes in SIBs for practical use.

Anion-derived cathode interface engineering enables ether-based electrolytes for sodium-ion batteries

High-performance sodium-ion batteries (SIBs) require not only non-aqueous electrolytes with high ion conductivity but also high interfacial compatibility with both electrodes. Ether-based electrolytes are considered one of the most promising electrolyte systems for SIBs due to the advantages of high reduction stability and weakly desolvating power. However, conventional ether-based electrolytes are easy to decompose and deteriorate on the cathode/electrolyte interface under high voltage, which greatly restricts their practical application in SIBs. Herein, a novel and effective interfacial stabilization strategy is proposed and systemically investigated. A homogeneous and compact cathode electrolyte interphase (CEI) film rich in fluorides and borides can be successfully constructed on the cathode surface by pre-cycling of NVP@C cathode in the NaODFB-DEGDME electrolyte. The ODFB anion-derived CEI film can effectively inhibit the continuous oxidation decomposition of NaPF6-DEGDME electrolytes. As a result, the Na||NVP@C half-cell can stably cycle for 1500 cycles with high average Coulombic efficiency (CE, >99.7 %) at 5C. This work illustrates the significance of the composition and structure of CEI film for improving the interfacial stability of high-voltage SIBs with ether-based electrolytes.

A novel Na8Fe5(SO4)9@rGO cathode material with high rate capability and ultra-long lifespan for low-cost sodium-ion batteries

Sodium-ion batteries (SIBs) are regarded as the most promising technology for large-scale energy storage systems. However, the practical application of SIBs is still hindered by the lack of applicable cathode materials. Herein, a novel phase-pure polyanionic Na8Fe5(SO4)9 is designed and employed as a cathode material for SIBs for the first time. The Na8Fe5(SO4)9 has an alluaudite-type sulfate framework and small Na+ ion diffusion barriers. As expected, the as-synthesized Na8Fe5(SO4)9@rGO exhibits a high working potential of 3.8 ​V (versus Na/Na+), a superior reversible capacity of 100.2 mAh g−1 at 0.2 ​C, excellent rate performance (∼80 mAh g−1 at 10 ​C, ∼63 mAh g−1 at 50 ​C), and an ultra-long cycling life (91.9% capacity retention after 10,000 cycles at 10 ​C, 81% capacity retention after 20,000 cycles at 50 ​C). We use various techniques and computational methods to comprehensively investigate the electrochemical reaction mechanisms of Na8Fe5(SO4)9@rGO.

Poly(p-phenylenediamine)-Coated Metal-Organic Frameworks for High-Performance Sodium-Ion Batteries: The Balance of Capacity and Stability.

Metal-organic frameworks (MOFs) with well-defined porous structures and highly active frameworks are considered as promising electrode materials for sodium-ion batteries (SIBs). However, the structure pulverization upon sodiation/desodiation impacts on their practical application in SIBs. To address this issue, poly(p-phenylenediamine) (PPA) was uniformly coated onto the surface of MIL-88A, a typical Fe-based MOF through in situ polymerization initiated by the metal ions (Fe3+) of MIL-88A. Used as an anode material for SIBs, the PPA-coated MIL-88A, denoted as PPA@MIL-88A, showed significantly improved electrochemical performance. A reversible capacity as high as 230 mAh g-1 was achieved at 0.2 A g-1 even after 500 cycles. MIL-88A constructed with electrochemically active Fe3+ and fumaric acid ligands guarantees the high specific capacity, while the PPA polymer coating effectively inhibits the pulverization of MIL-88A. This work provides an efficient strategy for improving the structure and cycling stability of MOFs-based electrode materials.

Optimization of sodium storage performance by structure engineering in nickel-cobalt-sulfide.

The development of high-performance electrode materials is crucial for the advancement of sodium ion batteries (SIBs), and NiCo2S4 has been identified as a promising anode material due to its high theoretical capacity and abundant redox centers. However, its practical application in SIBs is hampered by issues such as severe volume variations and poor cycle stability. Herein, the Mn-doped NiCo2S4@GNs composite electrodes with hollow nanocages were designed using a structure engineering method to relieve the volume expansion and improve the transport kinetics and conductivity of the NiCo2S4 electrode during cycling. Physical characterization and electrochemical tests, combined with Density functional theory (DFT) calculations indicate that the resulting 3% Mn-NCS@GNs electrode demonstrates excellent electrochemical performance (352.9 mA h g-1 (200 mA g-1) after 200 cycles, and 315.3 mA h g-1 (5000 mA g-1)). This work provides a promising strategy for enhancing the sodium storage performance of metal sulfide electrodes.

One dimensional pea-shaped NiSe2 nanoparticles encapsulated in N-doped graphitic carbon fibers to boost redox reversibility in sodium-ion batteries

In recent years, sodium-ion batteries (SIBs) have emerged as a promising technology for energy storage systems (ESSs) because of the abundance and affordability of sodium. Recently, metal selenides have been studied as promising high-performance conversion-type anode materials in SIBs. Among them, nickel selenide (NiSe2) has received considerable attention due to its high theoretical capacity of 495 mAh g–1 and conductivity. However, it still suffers from poor cycling stability because of the low electrochemical reactivity, large volume expansion, and structural instability during cycles. To address these challenges, NiSe2 nanoparticles encapsulated in N-doped graphitic carbon fibers (NiSe2@NGCF) were synthesized by using ZIF-8 as a template. NiSe2@NGCF showed a high discharge capacity of 558.3 mAh g–1 with a fading rate of 0.14% per cycle after 200 cycles at 0.5 A g–1 in 0.01–3.0 V. At a very high current density of 5 A g–1, the capacity still displayed excellent long-term cycle life with a discharge capacity of 406.1 mAh g–1 with a fading rate of 0.016% per cycle after 3000 cycles. The mechanism of the excellent electrochemical performance of NiSe2@NGCF was thoroughly investigated by ex-situ XRD, TEM, and SEM analyses. Furthermore, NiSe2@NGCF//Na3V2(PO4)3 full-cell also delivered an excellent reversible capacity of 378.7 mAh g−1 at 0.1 A g−1 after 50 cycles, demonstrating its potential for practical application in SIBs.

Boosting the Development of Hard Carbon for Sodium‐Ion Batteries: Strategies to Optimize the Initial Coulombic Efficiency

AbstractGiven the merits of affordable cost, superior low‐temperature performance, and advanced safe properties, sodium‐ion batteries (SIBs) have exhibited great development potential in large scale energy storage applications. Among various emerging carbonaceous anode materials applied for SIBs, hard carbon (HC) has recently gained significant attention regarding their relatively low cost, wide availability, and optimal overall performance. However, the insufficient initial Coulombic efficiency (ICE) of HC is the main bottlenecks, which is inevitably hindering their further commercial applications. Herein, an in‐depth holistic exposition about the reasons causing the unsatisfied ICE and the recent advances on effective improvement strategies are comprehensively summarized in this review, which have been divided into two aspects including the intrinsic property (degree of graphitization, pore structure, defect, et al.) and the extrinsic factor (electrolyte, electrode materials, et al.). In addition, future prospects and perspectives on HC to enable practical application in SIBs are also briefly outlined.

CuSe2 Nanocubes Enabling Efficient Sodium Storage.

As the most promising candidate for lithium-ion batteries (LIBs), the electrochemical performance of sodium-ion batteries (SIBs) is highly dependent on the electrode materials. Copper selenides have established themselves as potential anode materials for SIBs due to their high theoretical capacity and good conductivity. However, the poor rate performance and fast capacity fading are the major challenges to their practical application in SIBs. Herein, single-crystalline CuSe2 nanocubes (CuSe2 NCs) are successfully synthesized via a solvothermal method. As an anode of SIBs, the CuSe2 NCs render an almost 100% initial Coulombic efficiency, an outstanding long cycle life, e.g., 380 mA h g-1 after 1700 cycles at 10 A g-1, and an unprecedented rate performance of 344 mA h g-1 at 50 A g-1. Ex situ X-ray diffraction (XRD) patterns reveal the crystalline transformation of energy-storage materials, and the density functional theory (DFT) conclusion suggests that fast and stable ion diffusion kinetics enhances their electrochemical performance upon sodiation/desodiaton. The investigation into the mechanism provides a theoretical basis for subsequent practical applications.