High Rate Performance Research Articles

Sodium-Rich Prussian Blue Analogs Synthesized with Reducing Sodium Salt for Enhanced Rate and Cycling Stability Sodium-Ion Storage.

Prussian blue analogs (PBAs) as cathode material for sodium-ion batteries have attracted widespread attention due to their affordability, simple synthesis, and high theoretical capacity. Nevertheless, the oxidation of Fe2+ and sodium loss lead to poor electrochemical properties which restrict the practical use of PBAs. Herein, a simple coprecipitation approach based on sodium salt-reduction-assisted synthesis was proposed to construct high-sodium PBAs. The sodium bisulfite (NaHSO3) not only effectively inhibits the oxidation of Fe2+ but also increases the mole ratio of Na+ in the resulting products. The optimized sample exhibits excellent specific capacity (131.1 mAh g-1 at 0.1C), high rate performance (103.9 mAh g-1 at 10C), and good cyclic performance (94.8% capacity retention after 200 cycles). Experimental results reveal that the sample synthesized with sodium bisulfite possesses improved sodium-ion diffusion kinetics and stable crystal structure. In this study, a scalable method is introduced for the synthesis of PBAs with excellent electrochemical properties and further applications.

Dual Active Site Covalent Organic Framework Anode Enables Stable Aqueous Proton Batteries.

Aqueous proton batteries(APBs) have attracted increasing interest owing to their potential for grid-scale energy storage with extraordinary sustainability and excellent rate abilities. However, there are limited anode materials and it remains a great challenge to effectively balance capacity and cycling performance. Here, we report a covalent organic framework containing C=O and C=N dual active sites (TABQ-COF) as a high-capacity and long-cycle anode for proton batteries. The proton storage ability of the dual active sites and the up to nine proton redox chemistry mechanisms for each repetitive unit have been demonstrated by experiments and density functional theory calculations. The insoluble TABQ-COF electrode displayed a remarkably high specific capacity of 401 mAh g-1, outstanding cycling stability (100% capacity retention after 7500 cycles) and high rate performance (90 mAh g-1 at 50 A g-1). When coupling with a MnO2 cathode, the constructed TABQ-COF//MnO2 battery achieves a reversible capacity of 247 mAh g-1 at 5 A g-1,with a remarkable capacity retention of 100% over 10000 cycles. Furthermore, the TABQ-COF//MnO2 battery can operate well and shows high capacity and cycle stability in a frozen electrolyte at -40°C, implying great potential for energy storage at extreme temperatures.

Mesoporous Single-Crystal FeFe(CN)6 Microspheres for Superior Potassium-Ion Storage.

Metal hexacyanoferrates (HCFs), also known as Prussian blue analogues, are ideal cathodes for potassium-ion batteries (PIBs) due to their nontoxicity and cost-effectiveness. Nevertheless, obtaining metal HCF cathode materials with both long-term cycling stability and high rate performance remains a daunting challenge. In this study, we present mesoporous single-crystalline iron hexacyanoferrate (MSC-FeHCF) microspheres, featuring a single-crystalline structure that contains interconnected pores spanning the entire crystal lattice. This unique architecture not only enables the electrolyte to fully penetrate into the single crystal, but also shorten the K+ diffusion distance. Additionally, the confinement effect of mesopores on interior water mitigates the excessive side reactions. The stress during battery cycling can be dispersed through multiple paths to alleviate the internal strain. The MSC-FeHCF microspheres exhibit unprecedented long-term cycling performance, achieving a specific discharge capacity of 123.5 mAh g-1 at 30 mA g-1 and 87.1 mAh g-1 after 2000 cycles at 500 mA g-1, providing 85.8% of the initial capacity. More importantly, the MSC-FeHCF microspheres exhibit high rate capability, delivering 86.7 mAh g-1 at 3 A g-1. This study introduces an innovative strategy for engineering metal HCF cathode materials, thereby opening a novel avenue for the development of high-efficiency electrode materials for PIBs.

Sodium Ion Diffusion Behavior in Multiple Open/Closed Pore Ratios of Novel β-Cyclodextrin-Derived Hard Carbon Anode Materials.

Plateau-dominated hard carbon with a high rate of performance is challenging to obtain, and the in-depth mechanism of pore structure on the diffusion of sodium ions remains unclear. In this study, a facile liquid-phase molecular reconstruction strategy is proposed to regulate the orientation of the β-cyclodextrin molecules and prepare spherical hard carbon with continuous and ordered pore channels. Through detailed characterization, this approach is confirmed to optimize the accumulation of Na+ in the dispersion region, thus improving the plateau kinetics and enhancing the utilization of closed pores. The as-obtained β-cyclodextrin-derived spherical hard carbon has a much greater specific surface area (129 m2 g-1) than the pristine sample (2.91 m2 g-1) but a similar initial Coulombic efficiency. Additionally, the plateau region still exists when the current density is at 30 C (7.5 A g-1), contributing to a high capacity of 179 mAh g-1. This study provides a meaningful promotion to kinetics of hard carbon at the low-voltage region.

Tungsten Bronze W3Nb2O14 Nanorod: The Low-Strain and Preferred Orientation Enables Long-Life for High-Rate Lithium-Ion Storage.

Tungsten bronze oxides have emerged as attractive materials for energy storage owing to their fast charge-discharge property. However, the internal weakness of low capacity and short cycling performance impedes their development in wide application. In this work, the tungsten bronze W3Nb2O14 nanorods with preferred orientation (001) were prepared by hydrothermal method for the first time. It not only displays high-rate performance but also exhibits high capacity (201 mA h g-1 at 0.2 C) and long cycling property (80% capacity retention at 50 C after 3000 cycles). Notably, in situ XRD revealed the c evolution frustrates the V increase, and the maximum unit-cell volume expansion is only 2.9% during lithiation/delithiation, reflecting the long cycle performance is benefit from the low strain and preferred orientation. The ex-situ 6Li NMR spectra revealed that the lithiation and delithiation present preference based on the size of tunnels in the crystal framework.

Ionogel-Based Electrodes for Non-Flammable High-Temperature Operating Electrochemical Double Layer Capacitors.

The design of interfaces between nanostructured electrodes and advanced electrolytes is critical for realizing advanced electrochemical double-layer capacitors (EDLCs) that combine high charge-storage capacity, high-rate capability, and enhanced safety. Toward this goal, this work presents a novel and sustainable approach for fabricating ionogel-based electrodes using a renewed slurry casting method, in which the solvent is replaced by the ionic liquid (IL), namely 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide (EMIFSI). This method avoids time-consuming and costly electrolyte-filling steps by integrating the IL directly into the electrode during slurry preparation, while improving the rate capability of EDLCs based on non-flammable ILs. The resulting ionogel electrodes demonstrate exceptional electrolyte accessibility and enable the production of symmetric EDLCs with high energy density (over 30Wh/kg based on electrode material weight) and high-rate performance. These EDLCs could operate at temperatures up to 180°C, far exceeding the limitations of traditional EDLCs based on organic electrolytes (1M TEABF4 in acetonitrile, up to 65°C). Ionogel-type EDLCs exhibit remarkable stability, retaining 88% specific capacity after 10000 galvanostatic charge/discharge cycles at 10Ag-1 and demonstrating superior retention compared to conventional EDLCs (50%), while also maintaining 92.4% energy density during 100h floating tests at 2.7V. These electrochemical properties highlight their potential for robust performance under demanding conditions.

Li1.6AlCl3.4S0.6: a low-cost and high-performance solid electrolyte for solid-state batteries.

Solid electrolytes (SEs) are crucial for advancing next-generation rechargeable battery technologies, but their commercial viability is partially limited by expensive precursors, unscalable synthesis, or low ionic conductivity. Lithium tetrahaloaluminates offer an economical option but exhibit low Li+ conductivities with high activation energy barriers. This study reports the synthesis of lithium aluminum chalcohalide (Li1.6AlCl3.4S0.6) using inexpensive precursors via one-step mechanochemical milling. The resulting Cl-S mixed-anion sublattice significantly improves the ionic conductivity from 0.008 mS cm-1 for LiAlCl4 to 0.18 mS cm-1 for Li1.6AlCl3.4S0.6 at 25 °C. Structural refinement of the high-resolution XRD patterns and 6Li magic-angle-spinning (MAS) NMR quantitative analysis reveals the formation of tetrahedrally-coordinated, face- and edge-shared LiCl x S y octahedra that facilitate 3D Li+ transport. Ab initio molecular dynamics (AIMD) simulations on Li1.6AlCl3.4S0.6 support an enhanced 3D network for Li+ migration with increased diffusivity. All-solid-state battery (ASSB) half-cells using Li1.6AlCl3.4S0.6 exhibit high-rate and long-term stable cycling performance. This work highlights the potential of Li1.6AlCl3.4S0.6 as a cost-effective and high-performance SE for ASSBs.

An MgV3O8 anode exhibiting enhanced rate capability and stability for lithium storage applications.

The development of anode materials with high rate performance as well as favourable working durability is key for next-generation lithium-ion batteries (LIBs). Here, MgV3O8 is reported as an advanced anode material, using a facile and scalable solution combustion technology. The MgV3O8 anode shows a "near-zero" volume change (<10% over 1000 cycles). This can be explained by a solid-solution Li+ storage mechanism, leading to superior cycling stability. Consequently, the MgV3O8 electrode achieves a remarkable capacity of approximately 102.6 mA h g-1 at 2.0 A g-1, along with a low fading rate of 0.001% per cycle over 3000 cycles.

Preparation of NCM622 cathode material by complex combustion method and its energy storage performance

With the increasing demand for high-capacity and high-rate lithium batteries, ternary cathode materials with high-capacity and high-rate performance became more and more important. In order to obtain ternary cathode material with high performance, a combustion method was developed in this paper. Specifically, nickel, cobalt and manganese metal ions were fully complexed with organic matter (citric acid), assisted with the surfactant (polyvinyl pyrrolidone), and then a ternary cathode material (NCM622) precursor with nano-meter structure was prepared. After being performed with suitable calcination operations, the NCM622 cathode material was prepared. The obtained materials were characterized by XRD, SEM, XPS, particle size analysis and electrochemical performance tests. The results showed that the material obtained at 850 ℃ for 10h exhibited good dimensional uniformity, good layered structure and low lithium nickel mixing degree. Moreover, it had excellent electrochemical performance: its discharge specific capacity with general charge and discharge voltage range (2.8-4.3V) was up to 209.1 mAh.g-1 (0.2C), and its capacity decay rate was about 101.1% after 100 cycles at 0.5C in half-battery conditions. Even at 10C, it still had a discharge capacity of 116.4 mAh.g-1, showing excellent capacity and rate performance.

Needs Assessment for Public Health Competency in Infection Prevention and Control: Importance and Performance Analysis (IPA) of Infectious Disease Response Practitioners.

The Field Epidemiology Training Program Frontline, initiated by the Korea Disease Control and Prevention Agency in 2019, aims to enhance the competencies of infectious disease practitioners across 17 regions in South Korea. With the September 2024 amendment to the Infectious Disease Prevention Act mandating infectious disease prevention and crisis response training for government employees who are associated with infectious diseases responses, there is an urgent need to assess and optimize the effectiveness and cost-efficiency of such competency-based education programs amidst constraints of budget and manpower. This study examined the educational needs and priorities of public health competencies among infectious disease practitioners. The competency framework for Infectious Disease Response Practitioners (IDRP) in South Korea was used to evaluate the validity, importance, and performance level of competencies for infectious disease response personnel. For the training needs analysis, differences in performance by group were analyzed, and an importance performance analysis (IPA) was conducted using the Borich Needs Assessment based on the IPA matrix to derive training priorities. The analysis revealed a significant gap between perceived importance and self-reported performance levels in most competencies, especially epidemiologic methods. Competencies related to safety and ethics, fieldwork, and crisis management have high importance and performance ratings, indicating a need for ongoing training. Of the 27 competencies, the IPA identified specific training needs and priorities, suggesting eight competencies for focused intervention to strengthen the capacity of IDRPs. The IDRP competency framework in South Korea plays a pivotal role in establishing a standardized, competency-based approach to training IDRP. The identified gaps and training priorities highlight the need for continued curriculum development and the integration of real-world, field-based scenarios into training programs.

Facile fabrication of cellulose-derived hard carbon for high-rate performance sodium-ion batteries by regulating degrees of polymerization

We employ a molecular engineering strategy to regulate the polymerization degree of cellulose, resulting in the formation of multi-layered short graphite microcrystals and abundant closed pores, thereby achieving an outstanding rate performance.

Designing locally ordered structures of MnO2 for high-rate cathodes in aqueous zinc-ion batteries

A MnO2 cathode design is proposed. It combines locally ordered nanocrystallites with a long-range amorphous structure, improving ion transfer and electronic conductivity for enhanced high-rate performance in aqueous zinc-ion batteries.

Coffee Shortens Reaction Times and Enhances Performance in Taekwondo Simulations

In this study, the impact of coffee on taekwondo simulation performance and reaction times is examined. Pre- and post-consumption reaction times as well as performance metrics were measured during high-intensity simulated sparring sessions in a controlled trial with trained taekwondo practitioners. The subjects were split into two groups, one of which got a placebo and the other a caffeine supplement. The findings showed that as compared to the placebo group, the caffeine group exhibited noticeably faster reaction times and higher performance ratings. According to the research, coffee may be a useful ergogenic aid in martial arts, helping competitors perform better and be more responsive. The long-term consequences of caffeine consumption in combat sports and its implications for training regimens should be investigated further.

Heterostructure Design of Amorphous Vanadium Oxides@Carbon/Graphene Nanoplates Boosts Improved Capacity, Cycling Stability and High Rate Performance for Zn2+ Storage

AbstractAs a promising power supplier, flexible aqueous zinc ion batteries (AZIBs) have drawn great attention and been demonstrated potential applications in portable electronic devices, yet their capacity, stability, and rate performance are severely limited by cathode materials. Herein, a spontaneous encapsulation and in situ phase transformation strategy is proposed for the construction of heterostructured amorphous vanadium oxide@carbon/graphene (A‐VOx@C/G) nanoplates as highly stable and efficient cathode materials for Zn2+ storage. In this design, A‐VOx provides abundant active sites with rapid ion diffusion channels and robust tolerance against ion insertion/extraction, while N‐doped carbon encapsulation and interlaced graphene network ensure efficient electron transfer. The mechanisms respectively for phase transformation during electrochemical amorphization and charge storage during cycling are investigated in detail. The as‐prepared A‐VOx@C/G achieves an outstanding electrochemical performance with 429 mAh g−1 at 0.5 A g−1, 73% retained at 20 A g−1 (315 mAh g−1), and excellent stability over 2000 cycles at 20 A g−1 (91% retention). Moreover, quasi‐solid‐state AZIBs assembled from A‐VOx@C/G cathode exhibit high flexibility and can sustain large mechanical deformation without performance degradation. It is believed that this study provides a guideline toward designing high‐performance cathode materials for AZIBs through structure optimization.

High Rate Performance of Single‐Crystalline NCM Upcycled from Spent Lithium‐Ion Batteries Via Direct Recovery and Modification

AbstractThe global expansion of spent lithium‐ion batteries (LIBs) presents both an urgent environmental issue and a significant economic opportunity, driving the development of diverse recycling processes worldwide. Direct regeneration is a promising method for recovering materials from spent LIBs. However, most existing direct regeneration methods focus solely on recovering cathodes without addressing further improvements in their performance. Herein, a direct regeneration method is reported to upcycle single‐crystalline lithium nickel manganese cobalt oxides (NCM) from spent polycrystalline NCM based on a facile phosphoric acid etching approach. Moreover, the Li3PO4 coating and PO43− polyanion doping are simultaneously achieved on the surface of single‐crystal NCM during the upcycling single‐crystalline process. The enlarged lattice spacing and fast ionic conductor coating layer enhance Li+ diffusion and mitigate phase transformations during delithiation/lithiation. Benefiting from the synergistic effect of single crystal structure and surface modification, the upcycled single‐crystalline LiNi0.65Co0.2Mn0.15O2 demonstrates excellent electrochemical performances, including large reversible capacity (≈186 mAh g−1 at 0.1C), high‐rate capability (≈142 mAh g−1 at 10C), and excellent cycling stability (≈99% retention for 100 cycles). This approach provides a novel and effective upcycling pathway to transform the spent LIBs into value‐added cathode materials, achieving a win–win situation for environmental protection and resource conservation.

Leaders Inflate Performance Ratings for Employees Who Use Robots to Augment Their Performance

ABSTRACTWith robot usage becoming increasingly prevalent in contemporary workplaces, a key task for supervisors is conducting performance ratings in the context of employee‐robot value co‐creation. In this research, we explore whether, how, and when employees' robot usage affects supervisors' performance ratings. Drawing upon attribution theory, we suggest that supervisors might overestimate the performance of employees who use robots at work. Across a pilot study, two experiments, and one field study, we find that employees' robot usage is positively associated with supervisors' illusory performance transference (i.e., supervisors' belief that robot–associated performance should be attributed to employees who use robots at work). In turn, this transference is positively associated with high performance ratings for the respective employees. Furthermore, the supervisor–perceived experience of robots (i.e., supervisors' perceptions that robots are able to feel emotions and sensations) weakens this indirect effect. We conclude by discussing the theoretical and practical implications of our findings and future directions.

High-Capacity and Long-Life Aqueous Zn-SPAN Batteries with Tandem Catalysis.

Aqueous zinc-sulfur batteries are a high-capacity and cost-effective energy storage technology. However, the performance is plagued by the dissolution of intermediate polysulfides formed during conversion. Here, this issue is addressed by developing aqueous rechargeable Zn-sulfurized polyacrylonitrile (SPAN) batteries using tandem catalytic systems, containing water and tetraglyme (G4) with iodine (I2) additives. Mechanistic study and experiments reveal that the fully conjugated molecular configurations circumvent the formation of soluble polysulfides and enable reversible co-storage of H+/Zn2+ with multiple redox-active centers. The reduced I2 by G4 activates I-/I3 - redox couple in SPAN, reducing activation energy, and accelerating Zn-ion transfer kinetics. Additionally, it stabilizes the Zn anode by forming an organic-inorganic interphase that induces the generation of the predominant (002) plane. The as-assembled Zn-SPAN batteries exhibit excellent performances, with a high capacity of 1260.4 mAh g-1 at 0.2 A g-1, a high-rate performance (409.3 mAh g-1 at 5 A g-1), and a long cycling stability (81.8% capacity remained over 800 cycles at 2 A g-1). This work takes a crucial step forward in organosulfur compounds accompanied by multi-electron transfer for the high-performance aqueous zinc-ion batteries.

BioFire® Joint Infection Panel for Samples Other than Synovial Fluid.

Objectives: The early identification of infection-causing microorganisms through multiplex PCR panels enables prompt and targeted antibiotic therapy. This study aimed to assess the performance of the BioFire® Joint Infection Panel (BF-JIP) in analysing non-synovial fluid samples. Methods: We conducted a retrospective cohort study at Trieste University Hospital, Italy, on hospitalised adults with non-synovial fluid samples tested by both BF-JIP and traditional culture methods (November 2022-April 2024). Results: We evaluated 48 samples from 45 patients, including 24 abscess drainage fluids and 10 tissue samples. The BF-JIP showed high concordance (85.4%) and enhanced detection (4.3%) compared to culture methods. The BF-JIP excelled in cerebrospinal fluid (CSF) (100% accuracy and concordance) and in abscess drainage fluid (accuracy: 95.8%; concordance: 91.7%) identification and maintained high performance rates in patients under antibiotics. Conclusions: These findings suggest that BF-JIP is a valuable tool for accurate pathogen detection in various clinical samples, offering the additional advantage of being a rapid method.

High Data Rate MWD Mud Pulse Telemetry – From Mysteries to Discovery

Our new approach to MWD mud pulse telemetry offers significant increases over conventional data rates. Using waveguide acoustics, we show that common drilling communications channels support carrier frequencies exceeding several hundred Hertz. Such signals are prone to attenuation over large drillpipe distances. Low power, self-spinning “turbosirens” are designed, providing high torque and rotation rate performance at all flow rates without electric or hydraulic motor drives. The sirens rotate, drawing only on the kinetic energy of the mud, like flapping flags oscillating in wind. Our turbosirens are minimally affected by LCM jamming. Turbine and siren rotor components ride freely along longitudinal trenches built into rotating shafts. Both magically float into the oncoming mud as it slows down, thus, widening all gap spaces and freeing any trapped debris even as both travel opposite to the mud flow. In addition, “turbosirens in series” signal superposition, drawing on constructive wave interference, offers strong pressure signals at high frequencies without mechanical complexity. Rapid modulations are possible, also without motor drive, relying on rapidly acting electro-magneto rheological brakes powered by turbosirens. To take advantage of hardware capabilities, “Intelligent i FSK” telemetry, or Frequency Shift Keying creates clean signals without the ambiguous wave reflections found with PSK and randomized time shifts. Frequency pairs are not selected arbitrarily, but chosen from “neighboring pressure peaks and valleys” in frequency space as determined from bottomhole assembly waveguide Fourier analysis. Finally, surface signal processing and reflection removal are facilitated with time delay and differential equation algorithms. For deep wells where multiple drill pipe reflections are unlikely, analytical solutions for both are obtained assuming single reflections which do not involve windowing challenges and complicated digital filter design. Software and hardware developments patented, published and validated over the years, are integrated, refined and readied for controlled field tests.

Galvanic hydrogenation reaction in metal oxide

Rational reforming of metal oxide has a potential importance to modulate their inherent properties toward appealing characteristics for various applications. Here, we present a detailed fundamental study of the proton migration phenomena between mediums and propose the methodology for controllable metal oxide hydrogenation through galvanic reactions with metallic cation under ambient atmosphere. As a proof of concept for hydrogenation, we study the role of proton adoption on the structural properties of molybdenum trioxide, as a representative, and its impact on redox characteristics in Li-ion battery (LiB) systems using electrochemical experiments and first-principles calculation. The proton adoption contributes to a lattice rearrangement facilitating the faster Li-ion diffusion along the selected layered and mediates the diffusion pathway that promote the enhancements of high-rate performance and cyclic stability. Our work provides physicochemical insights of hydrogenations and underscores the viable approach for improving the redox characteristics of layered oxide materials.