Nanoparticles constructed mesoporous coral-like Mn2O3 as high performance anode for lithium-ion batteries

As well established, the morphology and architecture of electrode materials greatly contribute to the electrochemical properties. Herein, a novel structure of mesoporous coral-like manganese (III) oxide (Mn₂O₃) is synthesized via a facile solvothermal method coupled with the carbonization under air. When fabricated as anode electrode for lithium-ion batteries (LIBs), the as-prepared Mn₂O₃ exhibits good electrochemical properties, showing a high discharge capacity of 1090.4 mAh g^?1 at 0.1 A g^?1, and excellent rate performance of 410.4 mAh g^?1 at 2 A g^?1. Furthermore, it maintains the reversible discharge capacity of 1045 mAh g^?1 at 0.1 A g^?1 after 380 cycles, and 755 mAh g^?1 at 1 A g^?1 after 450 cycles. The durable cycling stability and outstanding rate performance can be attributed to its unique 3D mesoporous structure, which is favorable for increasing active area and shortening Li⁺ diffusion distance.     

Interface bonding engineering for constructing a battery-type supercapacitor cathode with ultralong cycle life and high rate capability

The low rate and poor cycle greatly limit the large-scale applications of supercapacitors electrodes in energy storage field. In this work, the SnS₂/Ni₃S₂ nanosheets arrays are bonded on N/S co-doped graphene nanotubes though N–Sn/Ni and S–Sn/Ni interface bonds employing a simple hydrothermal method to form a self-supported battery-type supercapacitors cathode. A series of characterization and DFT calculations indicate that the interface bonding not only automatically generates the internal electric field and allows more redox reactions to carry out easily, but also effectively reduces the OH^? ions adsorption energy and maintains the integration of the electrode structure. This unique design greatly promotes the electronics/ions transfer and reaction kinetics of the cathode, and substantially enhances its rate capability and durability. Detailedly, a high specific capacity of 296.9 mAh g^?1 at 2 A g^?1 is obtained. More impressively, the cathode still holds 155.6 mAh g^?1 when the current density is enlarged to 100 A g^?1, as well as it can retain 84% initial capacity over 50,000 cycles. Besides, an assembled asymmetric supercapacitor utilizing the prepared N/S-GNTs@B–SnS₂/Ni₃S₂ nanosheets arrays cathode and activated carbon anode presents a large energy density of 51 W h kg^?1 at 850 W kg^?1 and outstanding cycling stability. This work provides an effective strategy for improving rate capability and cycle lifespan of battery-type supercapacitors electrodes, and pushes the metal compounds forward a significant step in the practical applications of energy storage devices.     

Phase-engineering strategy of MoS2 nanosheets embedded in Bronze-TiO2 nanobelts for boosting lithium storage

Regulating the molybdenum disulfide (MoS₂) anodes with controllable phase and structure shows promising application for advanced lithium-ion storage performance. Herein, phase- and structure-regulated 1T@2H MoS₂ nanosheet @TiO₂–B nanobelts are synthesized via a facile hydrothermal and ammoniation strategy. The stable 1T@2H MoS₂ is revealed by the formation of N–Mo covalent bonds via subtle structural analysis, including XPS, Raman and TEM analysis. TiO₂ nanobelts serve as the backbone for MoS₂ nanosheets to form highly active edged nanostructure. As a proof-of-concept study, this well-devised 1T@2H MoS₂@TiO₂–B electrode delivers much higher capacities of 830 mA h g^?1 at 100 mA g^?1 after 200 cycles. Even at a large rate of 2000 mA g^?1, the reversible capacity was still maintained at 530 mA h g^?1 after 1000 cycles. In addition, the EIS, GITT and pseudocapacitance analyses further demonstrate the introduced 1T MoS₂ not only boost the lithium-ion diffusion coefficient, but also modify the electrochemical kinetics of the composite anodes. This concept of phase engineering strategy will open opportunities for advanced energy storage applications and beyond.     

Interconnected SnO2/graphene+CNT network as high performance anode materials for lithium-ion batteries

As a metal oxide with a high theoretical capacity, SnO₂ is considered to be one of the promising alternative anode materials in lithium-ion batteries. However, the pulverization of electrodes caused by the large volume expansion of SnO₂ during repeated charge/discharge hinders its practical application. Here, SnO₂ nanoparticles decorated on a 3D carbon network structure formed by the interconnection of graphene and CNT (SnO₂/G + CNT), which is designed and successfully synthesized via in situ chemical synthesis and thermal treatment. In this structure, the SnO₂ with nanosized can increase energy storage points and decrease the ions transport length, the carbon network can build a high conductive network that facilitates electron transport and alleviate the volume expansion to prevent electrode pulverization. In addition, graphene has a high specific surface area effect that facilitates lithium-ion storage, and the CNT also supports the graphene frame to make the carbon skeleton structure more stable, and provides a large number of ion transport channels, increasing the active sites of the reaction. Due to this excellent structure with synergistic effects, the SnO₂/G + CNT electrode exhibits superior reversible capacity (1227.2 mAh g^-1 at 0.1 A g^-1 after 200 cycles), superior rate capacity (549.3 mAh g^-1 at 3.0 A g^-1) and long cycle stability (1630.1 mAh g^-1 at 0.5 A g^-1 after 1000 cycles).     

Sb particles embedded in N-doped carbon spheres wrapped by graphene for superior K+−Storing performances

Antimony (Sb)-based nanocomposites have emerged as an attractive class of anode materials for potassium ion batteries as they exhibit large theoretical capacity and impressive working voltage. However, the tardy potassium ion diffusion characteristic, unstable Sb/electrolyte interphase, and huge volume variation pose a grand challenge that hinder the practical use of Sb-based anodes for potassium ion batteries. Herein, we develop a simple yet robust strategy to fabricate a three-dimensional N-doped carbon (N–C) porous microspheres and reduced graphene oxides (rGO) dual-encapsulated Sb hierarchical structures (denoted Sb@N–C/rGO), which are pursued for resolving the stubborn issues of Sb-based compounds for PIBs. As expected, such judiciously crafted Sb@N–C/rGO anode renders a set of intriguing electrochemical properties, representing a high reversible specific capacity of 586 mAh g^?1 at a current density of 0.2 A g^?1 after 200 cycles and excellent long-cycle stability of 358 mAh g^?1 at 1.0 A g^?1 after 1000 cycles. It is believed that the work can provide deep understanding and new insight to develop the alloying-type electrode materials for rechargeable batteries.     

NiSe2 encapsulated in N-doped TiN/carbon nanoparticles intertwined with CNTs for enhanced Na-ion storage by pseudocapacitance

Transitional metal selenides are considered as potential anode candidates for sodium-ion batteries (SIBs) because of their relatively high theoretical capacity and environmental benign. However, the large volume change derived from the conversion reaction and the sluggish kinetics due to the inherent low electrochemical conductivity hinder their practical application. Herein, composite materials of NiSe₂ encapsulated in nitrogen-doped TiN/carbon nanoparticles with carbon nanotubes (CNTs) on the surface (NiSe₂@N-TCP/CNTs) are fabricated via pyrolysis and selenization processes. In this composite, TiN inside the carbon matrix can enhance the conductivity and structural stability. CNTs that are in-situ grown on the surface not only further enhance the conductivity of the composites, but also offer sufficient space to buffer the volume expansion and alleviate serious aggregation of NiSe₂ nanoparticles. Benefit from these merits, the NiSe₂@N-TCP/CNTs showed a lower charge transfer resistance and a faster Na⁺ diffusion rate than materials without growing CNTs. When used as the anode of SIBs, the NiSe₂@N-TCP/CNTs electrode delivered a reversible capacity of 344.0 mAh g^?1 after 1000 cycles at 0.2 A g^?1, and still maintained at 272.7 mAh g^?1 even at a high current density of 2 A g^?1. The remarkable electrochemical performance is mainly attributed to the special designed hierarchical structures and pseudocapacitance sodium storage behavior.     

Electrochemical method integrating exfoliation and in-situ growth to synthesize MoS2 nanosheets/MnO2 heterojunction for performance-enhanced supercapacitor

Two-dimensional (2D) molybdenum disulfide (MoS₂) nanomaterials have become one of the promising options for constructing excellent supercapacitors. However, the application of MoS₂ materials is limited by low energy density, and the difficulty of large-scale and low-cost preparation seriously hinders its practical application in the field of energy storage. Here, the exfoliation of the MoS₂ nanosheets and the loading of MnO₂ nanoparticles on the MoS₂ nanosheets are realized in one step by electrochemical method. A series of characterization methods have fully confirmed that the electrochemical method has successfully prepared the MoS₂ nanosheet/MnO₂ (MoS₂ NS/MnO₂) heterojunction. The experimental results show that the MoS₂ NS/MnO₂ heterojunction has better electrochemical performance than a single MoS₂ nanosheet. It has a good capacitance even in a neutral solution, and its specific capacitance is 275 F g^?1 at a current density of 2 A g^?1. In addition, a supercapacitor device based on MoS₂ NS/MnO₂ heterojunction was constructed, which not only exhibited excellent capacitive performance, but also exhibited 10,000 charge-discharge cycle stability under 10 A g^?1 conditions. This work provides an experimental basis for the preparation of 2D nanosheets and the large-scale preparation of functionalized 2D material heterojunctions by electrochemical methods.     

Sucrose derived microporous–mesoporous carbon for advanced lithium–sulfur batteries

A microporous–mesoporous carbon has been successfully prepared via carbonization of sucrose followed by heat treatment process. The obtained porous carbon possesses abundant micropores and mesopores, which can effectively increase the sulfur loading. The composite exhibited a remarkable initial capacity of 1185 mAh g^?1 at 0.2 A g^?1 and maintained at 488 mAh g^?1 after 200 cycles, when employed for lithium?sulfur batteries. Moreover, the composite displayed enhanced rate capabilities of 1124, 914 and 572 mAh g^?1 at 0.2, 0.5 and 1.0 A g^?1. The outstanding electrochemical capabilities and facile low?cost preparation make the new microporous–mesoporous carbon as an excellent candidate for lithium sulfur batteries.     

PPy modified 1T-MoS2 hollow spheres with cohesive architecture as high-performance anode material for Li-ion batteries

A cohesive architecture of 1T-MoS₂ covered by PPy composite (1T-MoS₂@PPy) is successfully fabricated by a simple hydrothermal reaction followed by an in-situ polymerization route. The composite material consists of 1T-MoS₂ hollow microsphere and conductive PPy coating layer. The cohesive architecture enables the composite to show rapid shuttle of electrons/lithium ions and good ductility to buffer the volume changes during charging and discharging process when it is used as anode material. As expected, 1T-MoS₂@PPy composite exhibits a favorable discharge capacity up to 970.3 and 407.1 mAh g^?1 at 0.2 and 3 A g^?1, respectively. In addition, the composite also achieves impressive cycling performance of 717.1 mAh g^?1 at 1 A g^-1 after 500 cycles. This study provides a meaningful guidance in rational design of anode materials with cohesive architecture as well as high electrochemical performance.     

A facile polymer-pyrolysis preparation of submicrometer CoMoO4 as an electrode of lithium ion batteries and supercapacitors

In the present work, submicrometer CoMoO₄ is successfully prepared by a facile polymer-pyrolysis method. The phase, structure, composition and morphology of the obtained sample are characterized by several techniques. The proper reaction temperature is 600 °C. As an anode material of lithium half-battery, the sample prepared at 600 °C exhibits a stable reversible capacity of 667.6 mAh g^?1 at a current density of 0.2 A g^?1. A 96.7% capacity retention is observed between 10 and 100 cycles, where lithium storage reaction is dominated by ionic diffusion, and the diffusion coefficient of lithium ion is about 0.12 × 10^?15 cm² s^?1. As electrode of supercapacitors, a high specific capacitance of around 304.6 F g^?1 is achieved at a current density of 0.5 A g^?1 after 1000 cycles. Therefore, the polymer-pyrolysis method shows great promise in preparing the CoMoO₄.     

Improving electrochemical performance of NCM811 cathodes for lithium-ion batteries via consistently arranging the hexagonal nanosheets with exposed {104} facets

Layered high-nickel LiNi_0.8Co_0.1Mn_0.1O₂ is a promising candidate of the next generation cathode materials for lithium-ion batteries. However, severe cycling instability and fast capacity drop induced by anisotropic structured change restrict its wide application. To address these defects, the structure design of cathodes is conducted. Herein, a hierarchical layered LiNi_0.8Co_0.1Mn_0.1O₂ cathode consisting of orderly stacking hexagonal nanosheets with exposed active {104} facets is successfully synthesized by an improved co-precipitation process and followed with a high temperature lithiation reaction. Benefiting from this unique texture, exposed active {104} facets with lower surface energy supply 3D barrier-free Li⁺ ion diffusion channels, significantly improving the efficiency of the Li⁺ diffusion. Moreover, the consistent arrangement of nanosheets in the manner of the {001} facets close attachment is beneficial to alleviate the stress caused by the anisotropic structured change. Thus, this cathode material presents both superior reversible capability (203.8 mAh g^?1 at 0.1C, 184.5 mAh g^?1 at 1 C, 173.0 mAh g^?1 at 5 C and 161.3 mAh g^?1 at 10 C) and stable cycling performance (capacity retention of 89.3% after 100 cycles at 1 C, 55.3% after 300 cycles at 5 C and 59.6% after 300 cycles at 10 C).     

Engineering defect-enabled 3D porous MoS2/C architectures for high performance lithium-ion batteries

Designing defect-rich MoS₂/C architectures with three-dimensional (3D) porous frame effectively improve the electrochemical performance of lithium-ion batteries (LIBs) owing to the improved conductivity and decreased diffusion distance of Li⁺ ions for lithium storage. Herein, we report a reliable morphology engineering method combining with tunable defects to synthesize defect-rich MoS₂ nanosheets with a few layers entrapped carbon sheath, forming a 3D porous conductive network architecture. The defect-rich MoS₂ nanosheets with expanded interlayers can provide a shortened ion diffusion path, and realize the 3D Li⁺ diffusion with faster kinetics. A 3D conductive interconnected carbon network is able to improve interparticle conductivity, concurrently maintaining the structural integrity. Benefiting from these intriguing features, the as-prepared MoS₂/C architectures exhibit excellent electrochemical performance: a high reversible capacity of 1163 mAh g⁻¹ at a current density of 0.1 A g⁻¹ after 100 cycles and a high rate capability of 800 mAh g⁻¹ at 5 A g⁻¹. Defect content in MoS₂/C architectures can be obtained by changing H₂ concentration. Compared with the counterparts with few defects, the defect-rich MoS₂/C architectures show improved electrochemical stability with a superior cycle life, illustrating a highly reversible capacity of 751 mAh g⁻¹ at 0.5 A g⁻¹ after 500 cycles.     

Zn–Mn-ptcda derived two-dimensional leaf-like Zn0·697Mn0·303Se/C composites as anode materials for high-capacity Li-ion batteries

As the most widely used energy storage device today, lithium-ion batteries (LIBs) will determine the convenience and durability of people's future energy life to a certain extent. At present, there are many and mature researches on cathode materials for LIBs, so it is crucial to seek a high-performance anode material. In recent years, due to considerable theoretical capacity, abundant raw material reserves and unique physicochemical properties, Zn and Mn selenium compounds have become research hotspots for LIBs anode materials. In this work, a new MOF material Zn–Mn-ptcda was synthesized by a simple hydrothermal reaction. Using Zn–Mn-ptcda as the precursor, two-dimensional (2D) elliptical leaf-shaped Zn_0·697Mn_0·303Se/C composites were synthesized by direct selenization. Zn_0.697Mn_0.303Se/C has a large specific surface area of 213.9 m² g^?1, belongs to the mesoporous structure, and possesses excellent lithium storage performance, especially the rate performance. It has a reversible capacity of 1005.14 mAh g^?1 after 110 cycles at a current density of 100 mA g^?1. After 1000 cycles at a high current density of 1 A g^?1, it still maintains a good capacity of 653.79 mAh g^?1.     

Vertically aligned,polypyrrole encapsulated MoS2/graphene composites for high-rate LIBs anode

Ultrathin MoS₂ nanosheets were vertically anchored on the reduced graphene oxide (MoS₂/rGO) via hydrothermal method. To further engineering the surface conductivity, ultrathin polypyrrol (PPy) layer was coated on the MoS₂/rGO composite via in situ polymerization to form a bi-continuous conductive network with a sandwich-like structure. The graphene nanosheets and the PPy coating can facilitate the electrons transfer rate, while the ultrathin MoS₂ nanosheets can enhance the utilization efficiency of the active materials. The obtained MoS₂/rGO-10 composite exhibits high reversible specific capacity (970?mAh?g^?1 at 0.1?A?g^?1) and rate capability (capacity retention of 64% at 3.2?A?g^?1). Moreover, the PPy@MoS₂/rGO hybrids reveal lower specific capacity but better rate capability, and a “trade-off” effect between electrons and ions transfer resistance was observed. This easy-scalable PPy surface conductivity engineering strategy may be applied in the preparation of high-performance LIBs active materials.     

Graphene aerogel encapsulated Co3O4 microcubes derived from prussian blue analog as integrated anode with enhanced Li-ion storage properties

In lithium-ion batteries (LIB), cobalt oxide is considered an ideal anode material because of its theoretical specific capacity of up to 890 mAh g⁻¹, abundant resources, and low price. However, the volume expansion during the charging and discharging process and its lower conductivity have hindered its development. In this work, a metal-organic framework (MOF) was used as an initial template, encapsulated in graphene aerogels (GA) by hydrothermal and programmed temperature-controlled annealing and eventually formed into Co₃O₄ microcubes@GA composite. GA acts as a three-dimensional conductive network and mechanical skeleton, providing high electrical conductivity and structural stability to the composites. Moreover, the precursor's high porosity and stable structure are retained after annealing treatment. As an anode, the best long cycle life of Co₃O₄ microcubes@GA was achieved when the graphene oxide (GO) concentration was 3.0 mg ml⁻¹, reaching 1234.9 mAh g⁻¹ after 200 cycles at 1 A g⁻¹ with a coulomb efficiency (CE) of 98.97%.     

Construction of pseudocapacitive Li2-xLaxZnTi3O8 anode for fast and super-stable lithium storage

Lithium-ion capacitors (LICs) composed of battery-type anodes with large energy densities and capacitor-type cathodes with high power densities are considered as appealing energy-storage devices. Here, a LIC with good performance is constructed using active carbon (AC) as the cathode and Li_1.95La_0.05ZnTi₃O₈ (LL5ZTO) as the anode. LL5ZTO doped with La is synthesized via a one-step solid-state route. The kinetics and structural stability of LZTO are enhanced by La-doping. Thus, LL5ZTO exhibits good Li-storage performance. The discharge specific capacity reaches 182.6 mAh g^?1 at 3 A g^?1 (120th cycle) for LL5ZTO. The LIC based on the LL5ZTO anode and the AC cathode delivers an energy density of 59.72 Wh kg^?1 at 846.4 W kg^?1, and a high power density of 8771 W kg^?1 at 19.49 Wh kg^?1. Furthermore, the capacity retention is over 90% after 3000 cycles for the LIC at 2 A g^?1. The good electrochemical performance indicates that the constructed LIC is expected to use in advanced energy storage devices.     

Multilayer Si@SiOx@void@C anode materials synthesized via simultaneously carbonization and redox for Li-ion batteries

In the development of high-performance lithium-ion batteries (LIBs), the composition and structure of electrode materials are of critical importance. Silicon has a theoretical specific capacity 10 times that of graphite, nonetheless, its application as an anode material confronts challenge as it undergoes huge volume change and pulverization amidst the alloying and dealloying processes. Herein, a novel method to prepare a multilayer Si-based anode was proposed. Three layers, SiO₂, nickel and triethylene glycol (TEG), were coated successively on Si nanoparticles, which served respectively as the sources of SiO_x, sacrificial templates and carbon. Nickel can not only serve as a hollow template, but also play a catalytic role, which makes carbonization and redox reactions occur synchronously under a mild condition. Amid the carbonization process of TEG at 450 °C, several-nm-thick SiO₂ layer can react with the as-derived carbon to form a silicon suboxides (SiO_x (0 < x < 2)) intermedium layer. After removing the nickel template, a micro-nano scaled Si@SiO_x@void@C with conformal multilayer-structure can be obtained. The BET specific surface area and pore volume of powders were increased dramatically because of the derivation of abundant voids, which can not only buffer the swelling effect of silicon, but also provide richer ionic conductivity. The as-assembled half-cell with Si@SiOx@void@C as the anode material possesses high capacity (～1000 mAh g^?1 at 3 A g^?1), long cycle life (300 cycles with 77% capacity retention) and good rate performance (558 mAh g^?1 at 5 A g^?1).     

Tin antimony oxide @graphene as a novel anode material for lithium ion batteries

Bimetal oxides have attracted much attention due to their unique characteristics caused by the synergistic effect of bimetallic elements, such as adjustable operating voltage and improved electronic conductivity. Here, a novel bimetal oxide Sn_0.918Sb_0.109O₂@graphene (TAO@G) was synthesized via hydrothermal method, and applied as anode material for lithium ion batteries. Compared with SnO₂, the addition of Sb to form a bimetallic oxide Sn_0.918Sb_0.109O₂ can shorten the band gap width, which is proved by DFT calculation. The narrower band gap width can speed up the lithium ions transport and improve the electrochemical performances of TAO@G. TAO@G is a structure in which graphene supports nano-sized TAO particles, and it is conducive to the electrons transport and can improve its electrochemical performances. TAO@G achieved a high initial reversible discharge specific capacity of 1176.3 mA h g^?1 at 0.1 A g^?1 and a good capacity of 648.1 mA h g^?1 at 0.5 A g^?1 after 365 cycles. Results confirm that TAO@G is a novel prospective anode material for LIBs.     

Gill inspired hierarchical wrinkles of reduced graphene oxide encapsulated carbon nanotubes with significantly boosted supercapacitor performance

It has long been pursued in the energy storage community that 3D carbon materials can be constructed with 1D carbon nanotubes and 2D graphene in a proper manner that fully develops their appealing synergistic effects of high conductivity and large surface area. However, the present hybrid nanostructures suffer from either weak bonding strength or heavy dependence on high cost processing techniques. Here we report a gill-inspired hierarchical structure created by a simple annealing strategy, where carbon nanotubes are encapsulated in the wrinkles made of reduced graphene oxide, in resemblance to the vessels embedded in the wrinkle-like gill lamellae. The wrinkled structure enables enriched micropore structures and improved specific surface area, while the embedded carbon nanotubes guarantee the enhanced electrical conductivity. Thus, rGO@CNTs@AC (1000) achieved a 75% increase in the specific capacity @ 1 A g⁻¹ (200 F g⁻¹ vs. 120 F g⁻¹) when compared to a commericial AC in 1 M Et₄NBF₄/PC. In addition, the encapsulation strategy improved the supercapacitor stability by preventing the electrode materials from falling apart during the cycling. After 1000 cycles @ 1 A g⁻¹, the capacity retention rate of rGO@CNTs@AC (1000) remained above 90% while that of AC only maintained around 60%. More importantly, the proposed strategy should be applicable to general electrode materials for further improvement as supercapacitors. This work offers a novel bio-inspired strategy to effectively improve the supercapacitor performance by rationally designed hierarchical nanostructures.     

Construction of simultaneous modified Na3V2(PO4)3/C cathode with K/Zr substitution and carbon nanotubes enwrapping for high performance sodium ion battery

Na₃V₂(PO₄)₃ (NVP) has been deemed to be a prospective cathode material due to the unique NASICON-type framework for sodium ion battery (SIB). Nevertheless, the inferior intrinsic conductive property seriously impedes the development of NVP. Herein, the K/Zr co-substituted and carbon nanotubes (CNTs) enwrapped NVP/C composite is successfully synthesized through a facile sol-gel route. Notably, the introduced K⁺ in Na1 site possesses a pillar effect on the crystal structure to efficiently stabilize the framework. Meanwhile, Zr⁴⁺ with larger ionic radius successfully replaces of V³⁺, which is beneficial to expanding the interplanar spacing to facilitate the migration of Na⁺. Moreover, the enwrapped tubular CNTs can restrict the agglomerations of active grains to diminish the pathways for ionic and electronic transportation. Synthetically, the CNTs and amorphous coated carbon layers jointly construct a cross-linked 3D network to provide accelerated channels for electronic transportation. Consequently, the modified Na_2.96K_0.04V_1.93Zr_0.0525(PO₄)₃/C@CNTs composite exhibits superior electrochemical performance with excellent kinetic properties. Accordingly, it delivers a great capacity value of 110.8 mAh g^?1 at 0.1 C. Besides, it exhibits a reversible capacity of 102 mAh g^?1 at 2 C and maintains 89.7% after 300 cycles. As for a higher rate of 5 C, it releases an initial capacity of 99 mAh g^?1 and a high retention of 90.9% can be obtained after 1300 cycles. Significantly, the optimized sample delivers a high capacity of 91.2 mAh g^?1 at an ultra-high rate of 60 C and sustains 78.3% after 3000 cycles. Furthermore, the symmetric full cell is successfully fabricated and reveals superior high-rate capability with excellent stability. Therefore, this modified Na_2.96K_0.04V_1.93Zr_0.0525(PO₄)₃/C@CNTs composite would be a promising cathode material for practical applications in SIB.