Full Sodium-ion Batteries Research Articles

Dual-functional C-composited Na3.16Fe2.42(P2O7)2 cathode toward superior electrochemical performance for sodium-ion batteries

The development of a polyanion cathode for sodium-ion batteries is expected to accelerate the application of sodium-ion batteries in large-scale energy storage systems. However, the poor electrode conductivity is still a great challenge. In this paper, the novel carbon composite polyanion compound Na3.16Fe2.42(P2O7)2@C (NFP@C) is developed through high-energy ball milling followed by annealing. The porous NFP nanoparticles modified with dual-functional C-composited for amorphous carbon coating and carbon nanofibers interpenetrating deliver excellent capacity retention of 85.3% after 1000 cycles at 5 C, which is more outstanding than pure NFP. X-ray diffraction, in situ galvanostatic intermittent titration techniques, electrochemical impedance spectroscopy, and cyclic voltammetry were performed to investigate the stability and sodium diffusion of NFP@C. The results show that the systematic and comprehensive dual-functional conductive network modification enables NFP exhibit excellent electronic and ionic conductivities, thereby improving the rate capability and cycling stability. Furthermore, a soft package sodium-ion full battery assembled based on NFP@C reveals a high-capacity retention of 95.2% for 150 cycles at 0.5C. This carbon composite strategy is simple and efficient and could be easily and widely extended to other cathodes in grid-scale energy storage applications.

Binder-free 3D hierarchical Bi Nanosheet/CNTs arrays anode for full sodium-ion battery with high voltage above 4 V

Aiming to the repetitively large volume change and the inevitably loss of volumetric capacity of bismuth (Bi) based sodium-ion battery (SIB) during cycling, a binder-free Bi anode based on one-step electrochemical co-deposited three-dimensional Bi nanosheets and conductive carbon nanotube networks (Bi NS/CNTs) was developed. Compared with the sole Bi anode achieved via the same strategy, the co-deposition of 3D hierarchical Bi nanosheet/CNTs arrays manifests the strong interfacial adhesion and accommodates the volume change upon sodium alloying/dealloying. Such structural feature endows the Bi NS/CNTs anode a long-term cycling stability (383.72 mAh g−1 at 0.1 A g−1 after 200 cycles, 311.68 mAh g−1 at 1 A g−1 after 1000 cycles) and a good rate performance. A full SIB assembled with Bi NS/CNTs anode and Na3(VOPO4)2F@rGO cathode shows a high operating voltage (above 4 V) and a high energy density of 221.99 Wh kg−1, which outperforms many reported Bi-based analogues. This work may open a new opportunity for developing efficient SIB with high energy and good practicability.

A dynamic polyanion framework with anion/cation co-doping for robust Na/Zn-ion batteries

Among various cathode materials for sodium-ion batteries (SIBs), Na3V2(PO4)3 has an open and stable three-dimensional framework to reversibly (de)intercalate sodium ions (Na+), but its inherently insulated and stiff features originated from VO6 octahedron and PO4 tetrahedron result in limited capacity and poor rate performance. Herein, this work resolves these issues by implementing anion (Cl−) and cation (Mg2+) to respectively substitute a small fraction of O and V elements to expand Na+ migration channel and boost electronic conductivity, which is verified by both experiment and theory calculations. Even with carbon coating less than 1 wt% in content, which is one of the least carbon coating as reported, a dramatically improved capacity (120 mA h g−1 at 0.1 C) and rate performance (65 mA h g−1 at 30 C) are realized for Na3V1.95Mg0.05(PO4)2.9Cl0.1 in contrast to Na3V2(PO4)3 that merely releases 66.7 mA h g−1 at 0.1 C and decrease to 0 mA h g−1 at 30 C. Meanwhile, stable full SIBs and zinc-ion batteries are also demonstrated with this dynamic polyanion framework.

Exploration of a Na3V2(PO4)3/C –Pb full cell Na-ion prototype

Recent research focusses typically on sodium-ion half cells, and the progress of high performance and cost-effective full cells remains a critical obstacle to commercialize sodium-ion batteries. Here, we rationally design a full sodium-ion battery based on carbon coated Na3V2(PO4)3 (NVP-C) cathode and Pb anode materials. Carbon coated NVP is prepared via easy and one-step solid-state method. With 8 wt% carbon content, the obtained NVP-C core-shell structure provides an excellent reversible capacity of 104 mAh/g at C/10 rate, approaching towards its theoretical capacity. The NVP-C electrode even at a high 5 C rate delivers a primary reversible capacity of 87 mAh/g with 99.9% capacity retention almost after 3500 cycles. As an anode, Pb delivers an initial reversible capacity of 477 mAh/g at a fixed current density of 13 mA/g with a good cyclability and capacity retention of 98.5% over 50 cycles. The full cell constructed from the as-prepared materials exhibits a preliminary reversible capacity of 233 mAh/g at C/10 rate. In addition, the good rate capability including discharge energy density in the range of 170–180 Wh/kg makes the full cell a potential candidate in practical sodium-ion battery application. The excellent electrochemical behavior with simple, low-cost properties of fabricated full cell mark it as attractive option for high-energy energy storage applications.

Spatially Confined Synthesis of SnSe Spheres Encapsulated in N, Se Dual-Doped Carbon Networks toward Fast and Durable Sodium Storage.

On account of the high theoretical capacity and preferable electrochemical reversibility, tin selenides have emerged as potential anode materials in the field of sodium ion batteries (SIBs). Unfortunately, the large volume changes, low electrical conductivity, and shuttling effect of polyselenides have impeded their real application. In this work, we present a spatially confined reaction approach for controllable fabrication of SnSe spheres, which are embedded in polydopamine (PDA)-derived N, Se dual-doped carbon networks (SnSe@NSC) through a one-step carbonization and selenization method. The NSC shell can not only buffer the volume changes during the cycling but also ensure strong coupling interaction between the SnSe core and carbon shell through Sn-C bonds, leading to excellent conductivity and structural integrity of the composite. Meanwhile, DFT theory calculations confirm that N, Se codoping in the carbon shell can endow the composite with enhanced adsorption energy and accelerated transfer ability of Na+. Consequently, the SnSe@NSC anode exhibits a high discharge capacity of 302.6 mA h g-1 over 500 cycles at 1 A g-1 and a competitive rate capability of 285.3 mA h g-1 at 10 A g-1. Additionally, a sodium ion full battery is assembled by coupling the SnSe@NSC anode with the cathode of Na3V2(PO4)3 and verified with good cycling durability (190 mA h g-1 at 1 A g-1 over 500 cycles) and high energy density (204.3 W h kg-1). Our scalable and facile design of heterostructured SnSe@NSC provides a new avenue to develop novel advanced anode materials for SIBs.

Tin-Based Anode Materials for Stable Sodium Storage: Progress and Perspective.

Because of concerns regarding shortages of lithium resources and the urgent need to develop low-cost and high-efficiency energy-storage systems, research and applications of sodium-ion batteries (SIBs) have re-emerged in recent years. Herein, recent advances in high-capacity Sn-based anode materials for stable SIBs are highlighted, including tin (Sn) alloys, Sn oxides, Sn sulfides, Sn selenides, Sn phosphides, and their composites. The reaction mechanisms between Sn-based materials and sodium are clarified. Multiphase and multiscale structural optimizations of Sn-based materials to achieve good sodium-storage performance are emphasized. Full-cell designs using Sn-based materials as anodes and further development of Sn-based materials are discussed from a commercialization perspective. Insights into the preparation of future high-performance Sn-based anode materials and the construction of sodium-ion full batteries with a high energy density and long service life are provided.

Epitaxial growth induced multilayer yolk-shell structured CoSe2 with promoting transport kinetics of sodium ion half/full batteries

Metal-organic framework (MOF)-derived yolk-shell structures are one of the most potential nanoarchitectures applied in second batteries and electrocatalysis. In this manuscript, a multilayer yolk-shell structured CoSe 2 has been fabricated via post carbonization and selenization processes of step-by-step crystal epitaxial growth of multilayer solid zeolitic imidazolate frameworks (ZIFs) precursor. When used as the anode of a sodium-ion half battery, the obtained multilayer yolk-shell structured CoSe 2 materials can maintain a discharge capacity of 352.9 mAh g −1 after the 2000 cycles at the current density of 1 A g −1 , which can be attributed to the special multilayer yolk-shell structure by providing the fast sodium ion transport. Besides, it also delivers excellent electrochemical performance in the sodium-ion full batteries, which further demonstrate the outstanding electrochemical property of the obtained multilayer yolk-shell structured CoSe 2 electrode material. • The multilayered yolk-shell CoSe 2 nano-dodecahedrons was successfully prepared. • The multilayered CoSe 2 with hollow structure effectively buffer volume expansion. • The multilayered yolk-shell CoSe 2 shows excellent long-term cycle stability in SIB. • The Na-ion full cell exhibits excellent rate capacity and cycle performance.

Potassium doping towards enhanced Na-ion diffusivity in a fluorophosphate cathode for sodium-ion full cells

K+doping into the Na-site of a Na3V2(PO4)2O2F cathode creates Na vacancies and increases disordering in the crystal structure, which dramatically accelerates Na ion diffusivity with outstanding rate and cycle performances in sodium-ion full batteries.

Building a flexible and applicable sodium ion full battery based on self-supporting large-scale CNT films intertwined with ultra-long cycling NiCo2S4.

The major difficulties for the development of flexible energy storage batteries lie in the scalable manufacture of high-performance flexible electrodes with bending tolerance. In the present study, large-scale CNT films are prepared by a continuous production method and used to fabricate a self-supported flexible high-capacity conversion anode with ultra-long cycling life by the in situ growth of NiCo2S4 nanosheets tightly anchored on the CNTs. The CNTs produced via such a scalable method have interconnected porous channels, providing a large contact area between the active materials and electrolyte facilitating the electrochemical conversion reaction of NiCo2S4. An ultra-high rate capability is achieved in terms of a capacity of 280 mA h g-1 at 20 A g-1. The interlaced construction of NiCo2S4 nanosheets with CNTs and firm anchoring on the CNT film result in a remarkable ultra-long cyclability of the NiCo2S4/CNT electrode with a capacity retention rate of 96% after 7500 cycles. A flexible full battery device is further established with the NiCo2S4/CNT anode and Na3V2(PO4)3/CNT cathode with the sealed package of PDMS, exhibiting good cycling stability and mechanical durability under different bending states. The present work highlights a scalable flexible battery electrode material, and demonstrates its potential applications in flexible Na-ion batteries.

Advanced red phosphorus/carbon composites with practical application potential for sodium ion batteries

Although sodium ion batteries (SIBs) are one of the most promising battery technologies, their relatively low energy density impedes further development. This study presents the novel practical application potential of high-capacity red phosphorus (P) in full SIBs with reasonable energy density. Various optimization strategies are implemented systematically, which include the ball mill time, binders, conductive and electrolyte additives, and corresponding functional mechanisms are also conducted. In situ TEM and electrochemical characterization further indicate that the hybridization of hard carbon (HC) with desirable stability and phosphorus/carbon (PC) with large capacity is a preferred strategy to construct P-based full SIBs. The corresponding energy density is increased from 134 Wh Kg−1 (pure HC case) to 150 Wh Kg−1 (HC/PC case) through an electrochemical presodiation method. Notably, despite the various challenges faced by P anodes, the analysis conducted in this study is crucial for enabling the practical application of high-capacity phosphorus beyond laboratory research.

3D printed high-performance sodium ion and zinc ion full batteries

3D printing has unique advantages for the preparation of batteries. It is of great significance to 3D print sodium ion full batteries and aqueous zinc ion full batteries in view of the fact that they are very promising among post-lithium-ion batteries. Here, a facile 3D-printing strategy is proposed to fabricate sodium ion full batteries and aqueous zinc ion full batteries via the polymer-based inks with high active material content. The prepared electrode inks can be easily scaled up and have the shear thinning behaviors. Electrochemical analyses confirming that the 3D printed sodium ion full batteries and aqueous zinc ion full batteries both deliver high electrochemical performance. The former composed of sodium vanadium phosphate (Na3V2(PO4)3) cathode and anode delivers the high capacity (21 mAh g−1), high-rate capability (10 C), and long cycle stability (4000 cycles). Meanwhile, the latter constituted by vanadium dioxide (VO2(B)) cathode and zinc powders anode also reveals the high capacity (173 mAh g−1), high-rate capability (73 mAh g−1 at 1600 mA g−1), and long cycle stability. This 3D printing strategy provides a way to construct ultra-micro batteries, large-size batteries, and special-shaped batteries.

A low-cost NiSe2 derived from waste nickel foam as a high-performance anode for sodium ion batteries

Nickel selenide has a splendid future to become a hot anode for sodium ion batteries owing to the high theoretical capacity and unique electrical conductivity. Nevertheless, exploring low cost and high-performance nickel selenide is still critical to further application. Herein, NiSe2 with micro-structured features has been synthesized through a low-cost and one-step selenidation approach using disused nickel foam as raw material. Eminent reversible capacity (515 mAh g−1 at 0.1 A g−1), superior rate capability (310 mAh g−1 at 10 A g−1), and excellent cycling stability (318 mAh g−1 after 800 cycles at 1 A g−1) are exhibited for NiSe2 prepared at 550 °C for 4 h. Importantly, the initial Coulombic efficiency is also impressive (96%). Furthermore, the electrochemical mechanism is sufficiently explored by means of ex situ X-ray diffraction (XRD) and transmission electron microscopy (TEM). Besides, employing Na3V2(PO4)2F3@rGO as cathode and NiSe2 as anode has been assembled the sodium ion full battery, which delivers two high discharge plateaus of 1.86 and 2.72 V and reveals preeminent rate capacity and cycling stability. This work will come out with a new avenue for fostering the evolution of new metal selenide materials for energy storage and others.

Physics-based modeling of sodium-ion batteries part I: Experimental parameter determination

Sodium-ion batteries (SIBs) have been heralded as the most promising “beyond lithium” energy storage technology. This proclamation is based on recent technological trends and the outstanding performance of the state-of-the-art prototype 18650 and pouch cells. However, improving the design and performance of SIBs requires an in-depth understanding of the electrochemical behavior of the electrodes from both an experimental and physics-based modeling perspective. In this contribution, experimental characterizations of SIB electrode materials based on Na3V2(PO4)2F3 (NVPF) cathode and hard carbon (HC) anode are presented. The goal of this experimental investigation is to understand the individual electrode behavior and further elucidate relevant parameters for physics-based models. As a result, geometric, thermodynamic, and kinetic parameters are deduced from the two SIB electrodes. Based on the analyses of Na//NVPF and Na//HC half-cells, diffusion mass transport limitations and Ohmic losses are identified for both electrodes. These overpotential losses are equally present in full cell SIBs composed of NVPF and HC electrodes. These results are useful in the setup of SIB physics-based models.

Air/water/temperature-stable cathode for all-climate sodium-ion batteries

The development of high-performance cathodes for sodium-ion batteries (SIBs) is one key issue required for the success of large-scale energy storage systems. In addition to performance degradation during cycling, electrode materials are usually hampered by instability when stored in various environments severely restricting their practical application. Here, we report a stable cathode material that shows no obvious capacity attenuation in various storage conditions. The cathode is composed of regular and homogeneous Na 3 V 2 (PO 4 ) 2 O 2 F 0.99 Cl 0.01 (NVPFCl) microcubes, with electrochemical properties, including high specific capacity (128.2 mA h g -1 at 0.1 C), excellent rate capability (79.8 mA h g -1 at 20 C), long-term cycle life, and all-climate performance. Studies using in/ex situ characterization and electrode kinetics are implemented to reveal the possible reasons for the stability and electrochemical activity of NVPFCl. This work may provide a pathway for the development of all-climate and storage-stable SIB cathode materials. • Regular microcube-shaped NVPFCl as cathode material for SIBs • NVPFCl can be stored in air and water and at various temperatures • Structure evolution of NVPFCl before and after storage is studied via in situ XRD • NVPFCl exhibits notable rate capability, long cycle life, and all-climate stability Gu et al. report a stable Na 3 V 2 (PO 4 ) 2 O 2 F 0.99 Cl 0.01 cathode, which exhibits negligible capacity attenuation under various storage conditions, including 26 months of exposure to air, immersion in water, and storage at high/low temperatures. It also displays competitive electrochemical properties and all-climate performance in both half and full SIBs.

Alleviating mechanical degradation of hexacyanoferrate via strain locking during Na+ insertion/extraction for full sodium ion battery

Alleviating mechanical degradation of hexacyanoferrate via strain locking during Na+ insertion/extraction for full sodium ion battery

Rational Design of Yolk-Shell ZnCoSe@N-Doped Dual Carbon Architectures as Long-Life and High-Rate Anodes for Half/Full Na-Ion Batteries.

Transition-metal selenides (TMSs) have emerged as prospective anode materials for sodium ion batteries (SIBs), owing to their considerable theoretical capacity and intrinsic high electronic conductivity. Whereas, TMSs still suffer from poor rate capability and inferior cycling stability induced by sluggish kinetics and severe volume changes during de/sodiation processes. Herein, a hierarchical composite consisting of a zinc-cobalt bimetallic selenide yolk and nitrogen-doped double carbon shell (denoted as ZnCoSe@NDC) is engineered and fabricated successfully. The architecture of the as-fabricated material improves the Na-ion storage performance via increasing the electron transfer kinetics, accommodating volume expansion, and mitigating the generation of by-products. As expected, the ZnCoSe@NDC electrode delivers superior sodium storage performance with long cycling stability (344.5 mAh g-1 at 5.0 A g-1 over 2000 long-term cycles) and high-rate performance (319.2 mAh g-1 at 10.0 A g-1 ). Meanwhile, the NVP@C//ZnCoSe@NDC full SIB cells are constructed successfully, retaining 96.3% of its initial capacity at 0.5A g-1 after 200 loops. The outstanding electrochemical performance and the construction of hybrid SIBs will have far-reaching influences on the development of the various rechargeable batteries.

Aliovalent-Ion-Induced Lattice Regulation Based on Charge Balance Theory: Advanced Fluorophosphate Cathode for Sodium-Ion Full Batteries.

There are still many problems that hinder the development of sodium-ion batteries (SIBs), including poor rate performance, short-term cycle lifespan, and inferior low-temperature property. Herein, excellent Na-storage performance in fluorophosphate (Na3 V2 (PO4 )2 F3 ) cathode is achieved by lattice regulation based on charge balance theory. Lattice regulation of aliovalent Mn2+ for V3+ increases both electronic conductivity and Na+ -migration kinetics. Because of the maintaining of electrical neutrality in the material, aliovalent Mn2+ -introduced leads to the coexistence of V3+ and V4+ from charge balance theory. It decreases the particle size and improves the structural stability, suppressing the large lattice distortion during cathode reaction processes. These multiple effects enhance the specific capacity (123.8mAhg-1 ), outstanding high-rate (68% capacity retention at 20 C), ultralong cycle (only 0.018% capacity attenuation per cycle over 1000 cycles at 1 C) and low-temperature (96.5% capacity retention after 400 cycles at -25 °C) performances of Mn2+ -induced Na3 V1.98 Mn0.02 (PO4 )2 F3 when used as cathode in SIBs. Importantly, a feasible sodium-ion full battery is assembled, achieving outstanding rate capability and cycle stability. The strategy of aliovalent ion-induced lattice regulation constructs cathode materials with superior performances, which is available to improve other electrode materials for energy storage systems.

Solid-state fabrication of CNT-threaded Fe1-S@N-doped carbon composite as high-rate anodes for sodium-ion batteries and hybrid capacitors

Abstract Metal sulfide/carbon composites have emerged as promising sodium-storage anode materials because of their decent theoretical capacities and low cost. Nevertheless, conventional metal sulfide/carbon nanocomposites are generally prepared via wet-chemical methods such as solvothermal routes, which is fussy and hard to scale up for mass production. Herein, we develop a facile solid-state method, in which a Fe1−xS@N-doped carbon composite threaded by CNTs (FS@NC@CNT) is prepared by directly annealing a ball-milled mixture containing iron (III) diethyldithiocarbamate complex and graphitized multi-walled CNTs. Highly dispersed Fe1-xS nanophase in N-doped carbon together with the highly conductive graphitized CNT networks greatly facilitate ion transport and electron transfer and thus promote the conversion reaction kinetics. The FS@NC@CNT composite exhibits competitive reversible capacity (440 mAh g−1 at 0.05 A g−1), excellent rate capacity (330 mAh g−1 at 10 A g−1), and good cyclic stability (86.5% capacity retention after 450 cycles at 7 A g−1). Coupled with Na3(VO0.5PO4) 2F2 @GO cathode, the full sodium-ion battery (SIBs) exhibits a high capacity retention of 98% after 80 cycles at 0.2 A g−1. Inspired by such excellent sodium storage performance in both half and full SIBs, the potential application of the composite in sodium-ion hybrid capacitors (SIHCs) is further studies by coupling with zeolite-templated carbon as a cathode. The SIHC device can maintain 80% capacity after 4500 cycles at 1 A g−1.

Nitrogen Doped Carbon Coated Bi Microspheres as High-performance Anode for Half and Full Sodium Ion Batteries.

As two-dimensional (2D) materials, bismuth (Bi) has large interlayer spacing along c-axis (0.395 nm) which provides rich active sites for sodium ions, thus guaranteeing high sodium ion storage activity. However, its poor electrical conductivity, combined with its degraded cycling performance, restricts its practical application. Herein, Bi microsphere coated with nitrogen-doped carbon (Bi@NC) was synthesized. Owing to the unique Bi crystals and nitrogen-doped carbon layer, the obtained Bi@NC anode exhibited satisfactory cycling stability and superior rate capability. Moreover, after assembling Bi@NC anode with Na3 V2 (PO4 )3 @C cathode to full battery, excellent sodium storage performance was obtained (57 mA h g-1 after 2000 cycles at 1.0 A g-1 ).

Flexible quasi-solid-state sodium-ion full battery with ultralong cycle life, high energy density and high-rate capability

Flexible quasi-solid-state sodium-ion full battery with ultralong cycle life, high energy density and high-rate capability