Perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) shows promise as an organic electrode material for lithium-ion batteries, but its dissolution in organic electrolytes severely limits practical application. To address this, this study designed and synthesized two PTCDA-based conjugated microporous polymers (TAPB-PTCDA and PBAPD-PTCDA), aiming to suppress dissolution through polymerization while simultaneously increasing the density of electroactive carbonyl groups to enhance lithium storage performance. These materials were constructed using PTCDA as the electroactive center, coupled via C-N bonds with triamine (TAPB) and tetraamine (PBAPD) linkers, respectively. Structural characterization confirmed the successful synthesis of the target polymers, which exhibited excellent thermal stability (retaining approximately 80% of their mass up to 550 degrees C) and abundant microporous structures. Electrochemical tests revealed that PBAPD-PTCDA, with its higher carbonyl density and larger conjugated framework, delivered superior performance compared to TAPB-PTCDA. After 400 cycles at a current density of 0.5 A g-1, PBAPD-PTCDA maintained a high reversible specific capacity of 268.6 mA h g-1, significantly surpassing the 222.2 mA h g-1 of TAPB-PTCDA. This study demonstrates that increasing the density of electroactive carbonyl groups in conjugated microporous polymers through molecular design is an effective strategy for improving the lithium storage performance of organic electrode materials.

Coal-derived graphene quantum dots (GQDs), rich in oxygen-containing functional groups and exhibiting a high degree of crystallinity, were incorporated into polyacrylonitrile-based carbon nanofibers via electrospinning to fabricate GQD-reinforced carbon nanofibers. The GQDs formed a conductive framework within the fibers and intertwined to construct an integrated conductive network. This unique dual-conductive architecture enables the carbon nanofiber fabrics to achieve rapid charge/discharge performance. This architecture endowed the carbon nanofibers with abundant mesoporous and macroporous, while simultaneously providing efficient pathways for rapid ion transport within the electrolyte. When applied as self-supporting supercapacitor electrode materials, the resulting carbon nanofibers demonstrated excellent capacitance and rate capability. At a current density of 1 A g- 1, the specific capacitance reached 261 F g- 1. Under an ultra-high current density of 500 A g- 1, the capacitance retention remained as high as 52%.

NASICON-type Na4MnV(PO4)3 (NMVP) has attracted considerable attention for its open 3D framework and high theoretical capacity. However, the material suffers from relatively poor electronic conductivity, which limits its rate capability. Additionally, during charge and discharge process, the Jahn-Teller effect of Mn3+ can trigger lattice distortion, resulting in inferior cycling stability. In this study, nitrogen (N) was doped into the carbon layer of Na4MnV(PO4)3 via a sol-gel method to synthesize a series of Na4MnV(PO4)3-PVPX materials (x = 0, 0.01, 0.02, and 0.03). Among the series, NMVP/C-PVP0.02 exhibited outstanding performance, delivering a discharge capacity of 107.8 mAh g-1 at 0.2C and retaining 87.8% of its capacity after 100 cycles. Moreover, it maintained 71% of its initial capacity even after 1,500 cycles at 5C. Furthermore, a full cell assembled with a hard carbon anode (HC//NMVP/C-PVP0.02) achieved a discharge capacity of 84.5 mAh g-1 at 5C. This work presents a promising strategy for advancing the commercialization of polyanion-type cathode materials. The nitrogen-doped carbon coating effectively enhances the structural stability of NMVP and facilitates the rapid (de)intercalation of sodium ions, thereby improving its overall electrochemical performance.

The development of rapid and stable ionic conduction pathways is imperative for solid-state electrolytes to fulfil their role in achieving high-performance lithium metal batteries. In this study, a novel anthraquinone-based conjugated microporous polymer (PTAQ) was successfully designed and synthesized, and incorporated as a functional filler with polyacrylonitrile (PAN) to prepare a high-performance Li+-PTAQ-PAN composite polymer solid-state electrolyte. The successful synthesis of PTAQ was confirmed by FTIR, NMR, and XPS. Research indicates that the electron-rich carbonyl groups in PTAQ serve as effective lithium-ion binding sites, and DFT calculations demonstrated their ability to significantly promote lithium salt dissociation and establish fast and ordered lithium-ion transport pathways. The resulting 15 wt%Li+-PTAQ-PAN electrolyte exhibits high ionic conductivity (3.36 & times; 10-4 S cm-1 at 25 degrees C), a high lithium-ion transference number (0.68), and a wide electrochemical window (5.4 V) at room temperature. The formation of a LiF-rich solid electrolyte interphase facilitates uniform lithium deposition, which enables the Li+-PTAQ-PAN solid-state electrolyte to function reliably for over 2000 h at 0.025 mA cm-2. Furthermore, this stability translates to outstanding electrochemical performance in full cells, as evidenced by Li||LiFePO4 batteries maintaining a high specific capacity of 190.9 mAh g-1 after 800 cycles at 0.5 C and exhibiting remarkable rate capability. This work provides a new material design and strategy for developing safe and high-performance solid-state lithium batteries.

The high theoretical energy density and low cost of room-temperature sodium‑sulfur batteries (RT NaS batteries) make them promising for grid-scale energy storage, yet polysulfide shuttling and sluggish conversion kinetics impede their development. This study designed a phase-engineered multicomponent composite Mo2C/Fe0.5Mn0.2Ni0.3/FeCo/Ni3Mo3C (CAT) as an advanced sulfur host, which synergistically integrated adsorption, conduction, and electrocatalysis. The heterogeneous interface of the Mo2C matrix and Fe-based alloy phases induced a built-in electric field via interfacial electron coupling, which enhanced polysulfide adsorption through optimized d-band centers and significantly lowered the energy barrier of the solid-solid Na2S2/Na2S conversion rate-determining step. Consequently, the CAT S/C cathode exhibited a high initial capacity of 1308 mAh g-1 at 0.1C. It achieved an initial capacity of 1140 mAh g-1 at 1C and maintained stable performance over 1600 cycles with minimal decay. Furthermore, in situ impedance and distribution of relaxation times analyses revealed highly reversible interfacial kinetics and stable charge-transfer behavior during cycling. This study highlighted a rational phase-engineering strategy for constructing multiphase synergistic systems. Additionally, it provided deep mechanistic insights into interfacial electrocatalysis for stable RT NaS batteries.

F-doping creates vacancies, boosting Li + transport and structure, enabling a high rate and long cycle life for regenerated LiMn 2 O 4 .

Solid-state batteries are increasingly regarded as a key future energy storage option because they are highly safe and exhibit increased energy density, enabling them to address the drawbacks of traditional liquid lithium-ion batteries. Nevertheless, their industrial deployment is still hindered by obstacles, including significant interfacial resistance, limited ionic conductivity, and inadequate interface stability. To address these limitations, this work introduces a combined approach that employs defect modulation alongside rational structural design. A three-dimensional nanofibrous network composite solid electrolyte (NATP-TiO2-PAN) was fabricated via electrospinning, incorporating Al3+-doped oxygen-deficient NaTi2(PO4)3 (NATP) and TiO2 into a polyacrylonitrile (PAN) polymer matrix. Defect engineering via Al3+ doping introduces oxygen vacancies into the NATP framework. These vacancies broaden the electrochemical window and decrease the activation energy for Li+ transport, thereby enhancing Li+ mobility. Computational results indicate that the (110) crystal plane of NATP is strongly compatible with lithium metal, promoting stable Li+ adsorption and the formation of a passivated interface, thereby suppressing lithium dendrite growth. The NATP-TiO2-PAN composite electrolyte demonstrates a high ionic conductivity of 1.06 × 10-4 S cm-1 at 60 °C and a wide electrochemical stability window of 4.5 V. The assembled Li|NATP-TiO2-PAN|Li symmetric cell maintains stable cycling for more than 1100 h with minimal polarization, confirming effective dendrite suppression. Benefiting from the stabilized interface and mitigation of volume expansion, the assembled quasi-solid-state Li|NATP-TiO2-PAN|FeS2 battery delivers excellent cycling stability, retaining 350 mAh g-1 after 800 cycles at 500 mA g-1 and maintaining more than 50% capacity retention after 1500 cycles at 1000 mA g-1. This work provides a promising material design strategy and experimental foundation for developing highly safe, high-performance quasi-solid-state lithium-ion batteries (QSSBs).

Pyrite-type iron disulfide (FeS2), characterized by its abundance, high theoretical specific capacity, non-toxicity, and excellent thermal safety, has attracted extensive attention for secondary energy storage systems. However, liquid-phase electrolyte-based batteries often suffer from drastic volume changes in active materials and polysulfide shuttling during cycling, severely compromising cycling stability. In contrast, employing solid-state electrolytes can suppress these side reactions at the source, providing a promising pathway for the deep utilization of FeS2. Nevertheless, enhancing the conduction efficiency and long-term stability of Li+ in polymer matrices remains a major unresolved challenge. To address this issue, we synthesised a novel lanthanide-based metal-organic framework (La-MOF) material for the first time. Employing solution blending and electrospinning techniques, we uniformly embedded its porous microcrystals within a polyacrylonitrile network. Subsequently, by combining this network with lithium bis(trifluoromethanesulfonyl)imide, we successfully prepared a composite polymer electrolyte. The resulting composite polymer electrolyte (CPE) exhibited an ionic conductivity of 2.75 & times; 10-4 S cm-1 at 60 degrees C, a lithium-ion transference number of 0.84, and an electrochemical stability window extending up to 5.06 V. Theoretical simulations reveal that the La-MOF selectively immobilizes TFSI- anions via multi-site hydrogen bonding and coordination interactions, while facilitating rapid Li+ migration through continuous transport pathways. When paired with an FeS2 cathode, the CPE enables stable cycling with an initial discharge capacity of 828 mAh g-1 at 500 mA g-1 and a retained capacity of 686 mAh g-1 after 400 cycles. This work demonstrates a dual-anchoring mechanism for anion immobilization and cation conduction, providing a feasible strategy toward high-energy quasi solid-state batteries.

The practical application of aqueous Zn-ion batteries (AZIBs) is limited by uncontrollable dendrite growth at the Zn anode interface and parasitic reactions induced by moisture. A novel molecular anchoring strategy is proposed, which involves incorporating N-hydroxysuccinimide (NHS) as a multifunctional electrolyte additive to regulate Zn2+ deposition and stabilize the electrode-electrolyte interface. The rigid five-membered ring structure of NHS, together with its carbonyl (C & boxH;O) and N-hydroxyl (N & horbar;OH) functional groups, enables strong and orderly adsorption on the Zn surface, creating a spatial shielding and solvation regulation. This effect not only homogenizes the electric field and ion current to achieve dendrite-free zinc deposition but also effectively blocks water molecules from contacting the negative electrode, thereby suppressing hydrogen evolution and corrosion. The NHS-containing electrolyte demonstrates exceptional performance, with a cycle life of 4200 h at 1 mA cm-2/1 mAh cm-2 and a Coulombic efficiency of 99.83%. Furthermore, the fabricated Zn||NH4V4O10 full cells exhibit excellent cycling stability, retaining 80% of their initial capacity after 1000 extended cycles at 5 Ag-1. This work elucidates the synergistic mechanism through which NHS optimizes the electrolyte environment and regulates interfacial chemistry, thereby providing a scientific basis for the development of more efficient and stable AZIBs.

A Zn-doped regenerated LiMn 2 O 4 material exhibits high rate performance and excellent cycling stability.

The development of anode materials with high-rate capability and long-cycle stability is essential for advancing lithium-ion batteries (LIBs). Herein, we realize the rational modulation of 3D flower-like hierarchical NbOPO4 via...

Zinc-ion hybrid capacitors (ZHCs) represent a promising class of energy storage devices. However, the rational design of cathode materials rich in active sites for efficient Zn2+ storage remains challenging. Through a hierarchical modulation strategy designed to synergistically optimize the pore structure and surface chemistry of carbon material, we develop a N/P/O co-doped, coal tar pitch (CTP)-derived hierarchically porous carbon (NP-OPC) for effectively zinc storage. Acid oxidation effectively suppresses polycondensation of CTP, while pre-carbonization with N/P dopant generates an initial porous framework in the carbon precursor and a heteroatom-affine environment, collectively enhancing the efficiency of KOH activation and promoting heteroatom doping during carbonization. The resulting NP-OPC possesses a well-developed hierarchical porosity, an ultrahigh surface area of 3522.2 m(2) g(-1), and substantial heteroatom doping of N (similar to 6.12 at.%), P (similar to 2.07 at.%), and O (similar to 8.14 at.%). The structural properties provide sufficient active sites for Zn2+ adsorption, rapid ion/electron transport, and optimized surface physicochemical properties. Consequently, the NP-OPC based aqueous ZHC delivers an exceptional capacity of 207.3 mAh g(-1) at 0.2 A g(-1) and exhibits exceptional cycling stability, retaining 91.1% of its initial capacity after 30,000 cycles at 10 A g(-1). Moreover, the assembled pouch device achieves both high energy density (138.6 Wh kg(-1)) and superior durability (89.5% capacity retention after 70,000 cycles at 10 A g(-1)). Through ex situ analyses and theoretical calculations, we elucidate the charge storage mechanism and identify the origin of the enhanced performance. This study offers a new avenue for the design of high-performance carbon materials derived from CTP.

Na7V4(P2O7)4(PO4) cathode materials with the advantage of superior cycling stability have been considered promising cathode candidates for sodium-ion batteries. However, their practical application is limited by low capacity and electronic conductivity. To address this issue, a Na7V4(P2O7)4(PO4)@NSC composite material was successfully synthesized by constructing an N/S co-doped carbon layer coating. N/S co-doping introduces abundant defects and active sites in carbon, boosting electronic conductivity. The formation of the C-S-V bond activates the V4+/V5+ redox process, which creates a multi-electron reaction and enhances capacity. The composite exhibits a capacity of 113.8 mAh g-1 at 0.1C, which remains 80.8 mAh g-1 even at 30C. The symmetric full battery retained 73.5% of its capacity after 1000 cycles at 5C. These results confirm the feasibility of N/S co-doping for NASICON-type cathodes, providing a modification strategy for subsequent research on exploiting the multielectron reaction characteristics of such NASICON cathodes.

Iron sulfides have attracted much attention in the field of anode materials due to their high theoretical capacity and low cost. Nevertheless, in practical applications, their performance is still limited by volume expansion and short cycle life during electrochemical cycling. In this study, a one-step high-temperature vulcanization method was used to design and synthesize nanoscale Fe7S8@CNS materials. As an anode for sodium-ion batteries (SIBs), the Fe7S8@CNS electrodes exhibited excellent electrochemical performance, with a remarkably high rate capability (451.2 mAh g-1 at 10 A g-1) and outstanding long-term cycling stability (432.1 mAh g-1 at 5 A g-1 after 3400 cycles). Kinetic analyses demonstrated that the coating of nano-carbon layers, along with N-and Sdoped carbon on Fe7S8, effectively enhanced the sodium storage capacity, improved cyclic stability, and promoted electron transfer. Moreover, the N-and S-doped carbon provided numerous active sites for Na+ adsorption, thereby facilitating electrolyte infiltration and enhancing Na+ transport. This work presents a simple method for synthesizing metal sulfide anode materials with superior performance, offering valuable insight into the development of high-performance anode materials for SIBs.

The deficiency of cathode materials with efficient Zn2+ storage severely hinders the development of highperformance zinc-ion hybrid capacitors (ZHCs). Herein, a multi-level porous carbon material derived from coal tar pitch (CTP) with a well-designed pore size distribution is prepared. The process involves precarbonization of dicyandiamide (DCD) and CTP, followed by KOH-assisted pyrolysis. The bifunctional DCD (soft template/nitrogen source) and chemical activation of KOH, combing with the regulation of pyrolysis temperature, endow the optimized NPC-750 with developed porosity, large surface area of 3644 m2 g- 1, and favorable nitrogen/oxygen doping contents of 2.85/9.83 at. %. Thus, NPC-750 exhibits rich electrochemical active sites, rapid charge/mass transfer, and optimized physicochemical properties, including improved wettability to the electrode material and extra zincophilic sites derived from the pseudocapacitance of functional groups. The assembled ZHCs with NPC-750 cathode show a high capacity of 193.8 mAh g-1 at 0.2 A g-1, excellent rate performance of 97.0 mAh g-1 at 20 A g-1, and exceptional stability for 40,000 cycles with 91.8 % capacity retention. Moreover, the constructed quasi-solid-state device exhibits great Zn-ion storage performance, achieving an outstanding energy density of 125.3 Wh kg-1 at 154.5 W kg-1, surpassing many previous reports. This work sheds a light on the design of CTP-based carbon electrode for high-performance ZHCs.

Oxygen-deficient Mn2-xP2O7-y with modulated cation vacancies was synthesized using a solvothermal method; through the synergistic influence of these vacancies, the optimized manganese pyrophosphate anode (Mn1.93P2O7-y) exhibited enhanced electrochemical properties.

Fast-charging technology is indeed a critical technical problem for electric vehicles today. Improving the conductivity of electrode materials is one of the effective ways to solve this technical bottleneck. Here, we incorporated highly conductive MXene and carbon nanotubes into the electrode materials of Li4Ti5O12 (LTO) and LiFePO4 (LFP) to construct the composite electrode material 3D-LTO-CNT-MXene and 3D-LFP-CNT-MXene (named 3D-LTO and 3D-LFP). The 3D-LTO we synthesized demonstrated an impressive capacity of 146.2 mAh g−1 at a 20C rate (where 1C = 175 mA g−1), the 3D-LFP material exhibited a capacity of 104.6 mAh g−1 at a 20C rate (where 1C = 170 mA g−1). This remarkable rate capability can be attributed to the constructed three-dimensional conductive network, which facilitates enhanced electrical conductivity and electron migration rates, thereby promoting rapid charging and discharging of the batteries. Furthermore, we assembled a 3D-LTO||3D-LFP full cell, which demonstrated exceptional performance at a high rate of 10C (1C = 170 mA g−1), achieving an energy density of 68.34 Wh kg−1 and a power density of 1547.5 W kg−1. This work demonstrates the feasibility of constructing 3D highly conductive electrode materials for rapid charging and discharging at high rates. It paves the way for the commercial application of truly ultra-fast charging in electric vehicles.

With the massive use of electric vehicles, spent electrode materials with no application value pose a serious threat to resource reserves and ecosystems. Consequently, recycling the spent electrode materials appears to be imminent. This study considered that lithium iron phosphate (LiFePO4) within a water-stabilized voltage could undergo ionic leaching. Ammonium persulfate [(NH4)2S2O8], which has a high electrode potential, was used for selective leaching of the metal components from the spent LiFePO4 material. The effects of leaching temperature, time, and the solid-liquid ratio on the leaching effect were investigated. Under optimized conditions, 99.2 % of Li in the spent LiFePO4 could be leached effectively. The leaching reaction belonged to the typical chemical reaction control, and LiFePO4 was converted to FePO4 as Li+ was continuously leached into the solution. The leaching of the spent LiFePO4 using (NH4)2S2O8 did not require additional acids or bases to adjust the acidity of the solution, ensuring that the solution had a stable voltage. This strategy predicted that the selective leaching of metal components from the spent LiFePO4 material could be enhanced using (NH4)2S2O8, providing a certain basis for wet recovery in aqueous systems.