Rechargeable Research Articles

Modulation in Spin State of Co3O4 Decorated Fe Single Atom Enables a Superior Rechargeable Zinc-Air Battery Performance.

High-performance bifunctional electrocatalyst for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is the keystone for the industrialization of rechargeable zinc-air battery (ZAB). In this work, the modulation in the spin state of Fe single atom on nitrogen doped carbon(Fe1-NC) is devised by Co3O4 (Co3O4@Fe1-NC), and a mediate spin state is recorded. Besides, the d band center of Fe is downshifted associated with the increment in eg filling revealing the weakened interaction with OH* moiety, resulting in a boosted ORR performance. The ORR kinetic current density of Co3O4@Fe1-NC is 2.0- and 5.6 times higher than Fe1-NC and commercial Pt/C, respectively. Moreover, high spin state is found for Co in Co3O4@Fe1-NC contributing to the accelerated surface reconstruction of Co3O4 witnessed by operando Raman and electrochemical impedance spectroscopies. A robust OER activity with overpotential of 352mV at 50mA cm-2 is achieved, decreased by 18 and 60mV by comparison with Co3O4@NC and IrO2. The operando Raman reveals a balanced adsorption of OH* species and its deprotonation leading to robust stability. The ZAB performance of Co3O4@Fe1-NC is 193.2mW cm-2 and maintains for 200h. Furthermore, the all-solid-state ZAB shows a promising battery performance of 163.1mW cm-2.

A Promising Approach to Ultra-Flexible 1 Ah Lithium-Sulfur Batteries Using Oxygen-Functionalized Single-Walled Carbon Nanotubes.

Lithium-sulfur (Li-S) batteries represent a promising solution for achieving high energy densities exceeding 500Wh kg-1, leveraging cathode materials with theoretical energy densities up to 2600Wh kg-1. These batteries are also cost-effective, abundant, and environment-friendly. In this study, an innovative approach is proposed utilizing highly oxidized single-walled carbon nanotubes (Ox-SWCNTs) as a conductive fibrous scaffold and functional interlayer in sulfur cathodes and separators, respectively, to demonstrate large-area and ultra-flexible Li-S batteries with enhanced energy density. The free-standing sulfur cathodes in the Li-S cells exhibit high energy density maintaining 806 mAh g-1 even after 100 charge-discharge cycles. Additionally, oxygen-containing functional groups on the SWCNTs significantly improve electrochemical performance by promoting the adsorption of lithium polysulfides. Employing Ox-SWCNTs in both cathodes and interlayers, the study achieves high-capacity Li-S pouch cells that consistently deliver a capacity of 1.06 Ah and a high energy density of 909 mAh g-1 over 50 charge-discharge cycles. This strategy not only significantly enhances the electrochemical performance of Li-S batteries but also maintains excellent mechanical flexibility under severe deformation, positioning this Ox-SWCNT-based architecture as a viable, light-weight, and ultra-flexible energy storage solution suitable for commercializing rechargeable Li-S batteries.

Formation of H2O2 in Near-Neutral Zn-air Batteries Enables Efficient Oxygen Evolution Reaction.

Rechargeable Zn-air batteries (ZABs) with near-neutral electrolytes hold promise as cheap, safe and sustainable devices, but they suffer from slow charge kinetics and remain poorly studied. Here we reveal a charge storage mechanism of near-neutral Zn-air batteries that is mediated by formation of dissolved hydrogen peroxide upon cell discharge and its oxidation upon charge. This H2O2-mediated pathway facilitates oxygen evolution reaction (OER) at ~1.5 V vs. Zn2+/Zn, reducing charge overpotentials by ~0.2-0.5 V and mitigating carbon corrosion - a common issue in ZABs. The manifestation of this mechanism strongly depends on the electrolyte composition and positive electrode material, contributing up to ~60% of the capacity with ZnSO4solutions and carbon nanotubes. Enhancing the H2O2-mediated pathway offers a route to higher energy efficiency and durability in near-neutral ZABs, advancing practical, sustainable energy storage.

Metal-Mediated Chlorine Transfer for Molten Salt-Driven Thermodynamic Change on Silicon Production.

The development of silicon (Si) material poses a great challenge with profound technological advancements for semiconductors, photo/photoelectric systems, solar cells, and secondary batteries. Typically, Si production involves the thermochemical reduction of silicon oxides, where chloride salt additives help properly revamp the reaction mechanism. Herein, we unravel the chemical principles of molten AlCl3 salt in metallothermic reduction. Above its melting temperature (Tm ≈ 192°C), three AlCl3 molecules coordinate with each metal (M) atom (e.g., conventional Al andMg, or even thermodynamically unfeasible Zn) to form metal-AlCl3 complexes, M(AlCl3)3. In the molten AlCl3 salt media, all complexes directly lead to the universal formation of AlOCl byproduct and as-reduced Si spheres through internal Cl* transfer during the reduction reaction. Intriguingly, highly oxophilic metal (i.e., Mg) establishes additional energetic shortcuts in reaction pathways, where AlCl3 directly detaches an oxygen atom, accompanied by strong metal-oxygen interactions and Cl* transfer within the same complex. Moreover, the thermodynamic stability of the metal-AlCl3 complex residue (MAl2Cl8) and the microstructure of post-treated Si do change according to the metal choice, imparting disparate physicochemical properties for Si. This work offers insights into the scalable production of tailored Si materials for industrial applications, along with cost-effective operations at 250°C.

Electrostatic Aspect of the Proton Reactivity in Concentrated Electrolyte Solutions.

Water-in-salt electrolytes with a surprisingly large electrochemical stability window of ≤3 V have revived interest in aqueous electrolytes for rechargeable lithium-ion batteries. However, recent reports of acidic pH measured in concentrated electrolyte solutions appear to be in contradiction with the suppressed activity of the hydrogen evolution reaction (HER). Therefore, the fundamental thermodynamics of proton reactivity in concentrated electrolyte solutions remains elusive. In this work, we have used density functional theory-based molecular dynamics (MD) simulations and the proton insertion method to investigate how the HER potential shifts in concentrated LiCl solutions under both acidic and alkaline conditions. Our results show that the intrinsic HER activity increases significantly with the salt concentration under acidic conditions but remains relatively constant under alkaline conditions. Moreover, by leverage over finite-field MD simulations, it is found that a determining factor for the HER activity is the Poisson potential of the liquid phase, which increases in concentrated electrolyte solutions with comparable values from both density functional theory and point-charge models.

Energetics and Dynamics of Metal-Ion Coordination with Ionic Liquid Electrolytes: A Combined DFT and AIMD Investigation for Rechargeable Batteries

Energetics and Dynamics of Metal-Ion Coordination with Ionic Liquid Electrolytes: A Combined DFT and AIMD Investigation for Rechargeable Batteries

Hydro–Wind–PV–Integrated Operation Optimization and Ultra-Short-Term HESS Configuration

In order to address the challenges associated with optimizing multi-timescale operations and allocating ultra-short-term energy storage for HWP integration, this study takes into account both the economic and reliability aspects of the HWP integration base. It proposes a model for optimizing operations and allocating energy storage capacity, achieving optimization across long-term, short-term, and ultra-short-term operations for an MECB. Initially, operation optimization is implemented for an entire group of terraced hydropower plants by regulating them with annual regulating capabilities on a long-term timescale. The objectives are to maximize the daily average minimum output and annual power generation. Subsequently, short-term operation optimization focuses on maximizing HWP power feed-in, minimizing new energy power curtailment, and reducing residual load standard deviation while ensuring the guaranteed output optimization results for the long term. Finally, to mitigate ultra-short-term fluctuations in new energy, a HESS with specified capacity and power is configured with the goal of minimizing comprehensive costs. Additionally, to address the challenge of smoothing negative fluctuations, which is hindered by charging and discharging efficiency limitations, a variable baseline is introduced, deviating from the conventional 0 MW baseline. A simulation study based on data from the hydro–wind–PV hybrid project in the Beipanjiang River Basin, China, demonstrates the following: (1) after long-term system optimization, the total power generation capacity of the system increases by 9.68%, while the peak-to-valley difference in output is significantly reduced; (2) short-term system optimization significantly reduces both the average variance in residual loads and the amount of power curtailed over five representative days; (3) the system incorporates 398.62 MWh of lithium-ion battery storage with a power of 412.47 MW and 51.09 MWh of supercapacitor storage with a power of 223.32 MW, which, together, completely smooth out the ultra-short-term fluctuations in new energy output.

Mxene and GaIn Alloy Nanostructures Regulate Zn Surface Ion Deposition for High-Performance Zinc-Ion Battery.

Zinc is an ideal energy storage material because of its low toxicity, nonflammability, and good biocompatibility. However, the commercial application is seriously hindered due to problems such as dendrite growth, hydrogen evolution, and interface passivation caused by "dead zinc" in the process of cyclic deposition. Herein, a nanoscale deposition dispersion model is designed in order to achieve directional deposition and uniform distribution of zinc ions for the growth of interfacial dendrites. Liquid metal GaIn was combined with Mxene for this nanostructure, which provides a rapid ion transfer channel to achieve lower overpotentials, a more uniform electric field distribution, and stronger corrosion resistance in a core-shell structure to achieve interface reaction suppression. The material was coated on the surface of the zinc metal as an artificial protective layer. It has a better cycle life at 1 mA·cm-2 compared with the bare Zn metal anode, achieving a long cycle time of 1100 h and an ultralow voltage lag (28.1 mV). It maintains the stability for 1000 cycles at 1 mA·cm-2 after assembling the complete battery. This provides a way to improve the performance of zinc-ion secondary batteries and paves the way for the next generation of energy storage devices.

Skeletal Rearrangement of Azo Compounds Enables Low‐Potential, High‐capacity Organic Anodes for Rechargeable Alkaline Batteries

The widespread adoption of rechargeable alkaline batteries is plagued by the performance‐limiting metal anodes, which are prone to (electro)chemical corrosion and raise environmental or economic concerns. Organic redox‐active materials offer a potential solution, but they typically struggle with dissolution‐induced degradation and insufficiently negative reduction potentials. Herein, we introduce benzo[c]cinnoline and its derivatives (collectively referred to as BCCs), a class of aromatic azo compounds with fused‐ring structure, as promising organic anode materials. BCCs exhibit pronounced aromaticity and Brønsted basicity, conferring low reduction potentials and intrinsic insolubility in alkaline solutions. Paired with the industrially established nickel hydroxide cathode, these batteries deliver high capacity (297 mAh g−1anode), output voltage of 1.3 V, and extended cycle life (≈ 16000 cycles). Notably, they also operate efficiently at extremely low temperatures down to −85 °C with an 8 M KOH electrolyte. We further explore the feasibility for all‐organic alkaline batteries by paring BCCs with the dihydro form of 4,4'‐azopyridine, utilizing azo compounds for both anode and cathodes. This chemistry leverages the unique properties of small organic molecules to achieve batteries with high capacity (236 mAh g–1), fast charging (1200 C), and easy recyclability.

Skeletal Rearrangement of Azo Compounds Enables Low‐Potential, High‐capacity Organic Anodes for Rechargeable Alkaline Batteries

The widespread adoption of rechargeable alkaline batteries is plagued by the performance‐limiting metal anodes, which are prone to (electro)chemical corrosion and raise environmental or economic concerns. Organic redox‐active materials offer a potential solution, but they typically struggle with dissolution‐induced degradation and insufficiently negative reduction potentials. Herein, we introduce benzo[c]cinnoline and its derivatives (collectively referred to as BCCs), a class of aromatic azo compounds with fused‐ring structure, as promising organic anode materials. BCCs exhibit pronounced aromaticity and Brønsted basicity, conferring low reduction potentials and intrinsic insolubility in alkaline solutions. Paired with the industrially established nickel hydroxide cathode, these batteries deliver high capacity (297 mAh g−1anode), output voltage of 1.3 V, and extended cycle life (≈ 16000 cycles). Notably, they also operate efficiently at extremely low temperatures down to −85 °C with an 8 M KOH electrolyte. We further explore the feasibility for all‐organic alkaline batteries by paring BCCs with the dihydro form of 4,4'‐azopyridine, utilizing azo compounds for both anode and cathodes. This chemistry leverages the unique properties of small organic molecules to achieve batteries with high capacity (236 mAh g–1), fast charging (1200 C), and easy recyclability.

Intelligent fuzzy-PSO based grid connected solar EV charging station for electric buses to enhance stability and energy management

Abstract Modern power networks are relying more and more on Distributed Generation (DG) and solar energy-powered Electric Bus (EB) charging stations; nevertheless, controlling the charging process under situations of peak EB load and variable solar irradiation presents considerable hurdles. This study presents a coordinated control approach that maximizes energy distribution for solar (PV)-based EB charging stations by using an intelligent energy management system (IEMS). Through the analysis of load demand and meteorological data in real time, the IEMS optimizes PV generation and grid power consumption, thereby halving peak power demand, minimizing system losses, and easing distribution grid stress. In order to enable dynamic modifications to the energy flow between PV power, the grid, and battery storage, the method integrates an adaptive neuro-based fuzzy control system that anticipates solar energy generation and predicts EB load demands. Furthermore, to balance power distribution between battery and ultracapacitor systems and control energy storage in ultracapacitors, a fuzzy inference system optimized using Particle Swarm Optimization (PSO) is utilized. This prolongs battery life and guarantees effective energy management. The overall performance of the IEMS is improved by the fuzzy logic controller, which produces output signals that specify the best power distribution for any energy storage system. Digital simulations and a real-time hardware-in-loop experimental setup are used to validate the effectiveness of the proposed system, which shows notable gains in energy management, grid stability, and system efficiency. In order to improve intelligent energy management in grid-connected solar-powered systems, this study offers a viable method for incorporating renewable energy sources into EB charging stations.

Prototipe Pembangkit Tenaga Surya Kapasitas 20 Watt Peak Sebagai Sumber Utama Tenaga Listrik Autonomous Buoy

This research aims to examine the use of 20 Watt Peak photovoltaic energy as the main power supply of the prototype on the autonomous buoy because it is able to absorb energy from direct sunlight. Experimental research methods are used to measure voltage, current, and electrical power on components such as photovoltaic, solar charger controller, battery, and electric motor. Tests were conducted by varying the motor speed to analyze the power usage and the time taken to recharge the battery in a span of 10 minutes, to identify factors affecting the performance of the autonomous float. The test results show that at 0% motor speed, no power is used as the motor is not rotating. However, at 25% motor speed, the motor started to use 50.93 watts of power. When the motor speed was 100%, there was a considerable increase in power consumption, where the power consumption increased to 112.86 watts. Thus, these results show that the higher the motor speed, the more power is required. The test shows the change in buoy voltage when not working or when charging for 10 minutes. At 0% motor speed, the initial voltage remains 12 Volts. When charged, the voltage remains 12 Volts because it is not being used. At 25-50% motor speed, the voltage drops from 10 Volts when charging to 12 Volts. At 75-100% motor speed, the initial voltage of 9-10 Volts rises to 10-11 Volts when charging. This shows an increase in voltage when the buoy is charging autonomously or when it is not working. The conclusion of this research is that an understanding of the energy usage performance of autonomous buoys is necessary to optimize the energy usage of 20 Watt peak photovoltaic as a renewable energy source.

Optimising Grid-Connected PV-Battery Systems for Energy Arbitrage and Frequency Containment Reserve

This study introduces a novel method for optimising the size and control strategy of grid-connected, utility-scale photovoltaic (PV) systems with battery storage aimed at energy arbitrage and frequency containment reserve (FCR) services. By applying genetic algorithms (GA), the optimal configurations of PV generators, inverters/chargers, and batteries were determined, focusing on maximising the net present value (NPV). Both DC- and AC-coupled systems were explored. The performance of each configuration was simulated over a 25-year lifespan, considering varying pricing, solar resources, battery ageing, and PV degradation. Constraints included investment costs, capacity factors, and land use. A case study conducted in Wiesenthal, Germany, was followed by sensitivity analyses, revealing that a 75% reduction in battery costs is needed to make AC-coupled PV-plus-battery systems as profitable as PV-only systems. Further analysis shows that changes in electricity and FCR pricing as well as limits on FCR charging can significantly impact NPV. The study confirms that integrating arbitrage and FCR services can optimize system profitability.

99.6% efficiency DC-DC coupling for green hydrogen production using PEM electrolyzer, photovoltaic generation and battery storage operating in an off-grid area

This paper presents a novel connection and control strategy for a hydrogen generation system using a proton exchange membrane electrolyzer powered by solar energy in an off-grid area without network backup. Given that, the proposed architecture is based on the indirect control of the Photovoltaic plant (achieved by removing a power-converter), the presented solution is more efficient and more reliable than the traditional scheme. Furthermore, with this innovation one can reach the same hydrogen production with smaller electrolyzers.The methodology includes detailed models of the photovoltaic panel and the electrolyzer, along with a control strategy that considers the degradation mechanisms of the electrolyzer to ensure reliable and prolonged operation. The results show that the proposed strategy keeps the operating power of the electrolyzer constant, even under variations in irradiance, thanks to energy storage in batteries. It is demonstrated that the proposed system offers efficiency above 99.6% during the analyzed period, with a 100% utilization rate of the electrolyzer, avoiding periods of inactivity and high current peaks. The study also includes simulations and experimental tests that confirm the feasibility and effectiveness of the presented solution, highlighting its advantages in terms of efficiency and investment costs compared to direct connections and other existing methods.

Chiral electrolytes for rechargeable metal batteries

Charge transfer at the liquid (electrolyte)-solid (metal) interfaces is of fundamental importance to metal electrochemical deposition that further determines the reversibility and kinetics of energy-dense rechargeable metal batteries (RMBs). We demonstrate the fast charge transfer at the electrolyte-metal interfaces for lithium metal by designing and synthesizing electrolytes with chiral solvents: R (or S)-1,2-dimethoxypropane (R-DMP or S-DMP) and R (or S)-4-methyl-1,3-dioxolane (R-MDOL or S-MDOL). The chiral-induced spin selectivity is considered to produce spin-polarized metal surfaces, enabling the improvement in charge transfer rate and efficiency. The deposited Li metal in chiral electrolytes shows smooth and uniform morphologies, as well as high initial (>95%) and average (∼99.2%) Coulombic efficiency for Li metal stripping/plating process, thus prolonging the life-span of batteries using thin lithium anode (50 μm) to 400 cycles till 80% capacity retention. This work provides a distinct approach to regulate metal deposition beyond the limitation of ion de-solvation.

Lead-acid battery desulfation using a high-frequency pulse desulfator in standalone PV systems

The work presented in this article contributes to the study of a standalone photovoltaic (PV) system with battery storage by creating an electronic board that allows for the recovery of the battery's capacity using pulse technology that uses high-energy pulses from the PV panel to break down and remove the sulfation buildup, which is a contributing factor in the failure of most lead-acid batteries. Different methods or treatments can be used to lessen the impact of sulfation or even get rid of it and achieve battery rejuvenation. Battery sulfation is a process in which sulfate crystals form on the plates of a lead-acid battery, impeding its ability to retain a charge, and decreasing the battery’s overall effectiveness. This process can happen due to various reasons, such as charging for a shorter time than required, charging for a longer period of time than required, or even not charging it for quite some time. Sulfation affects a battery’s lifespan and comes with adverse effects on its performance, though it can be prevented.

Optimized Smart Home Energy Management System: Reducing Grid Consumption and Costs through Real-Time Pricing and Hybrid Architecture

Utility authorities utilize various methods to promote end-user energy conservation, including higher tariff rates and demand response (DR) strategies. This paper investigates an Optimized Smart Home Energy Management System (OSHEMS) designed to minimize grid dependence and energy bills while ensuring reliable load delivery. A hybrid architecture prototype was implemented, integrating a photovoltaic (PV) array, battery storage, and the electrical grid. The system combines Maximum Power Point Tracking (MPPT) solar chargers and Pure Sine Wave (PSW) inverters for efficient energy management. The Home Energy Management Whale Optimization Algorithm (HEMWOA) was employed to optimize energy usage and achieve cost reduction while enhancing user comfort. Real-time pricing (RTP) tariffs incentivizing flexible energy consumption during peak hours were incorporated. OSHEMS manages, schedules, and monitors energy sources and appliances, determining the optimal consumption mix. Experimental results demonstrate a significant decrease in grid reliance (46.6%) and energy costs (57.7%) compared to non-scheduling scenarios. These findings highlight the potential of OSHEMS in promoting sustainable and cost-effective energy consumption in smart homes.

Feasibilty of UVC-LED/H2O2 Advanced Oxidation Processes as a Hybrid Water Treatment System Uniting Secondary Battery and Microbial Fuel Cell

An innovative hybrid water treatment system consisting of an ultraviolet C light-emitting diode sequentially connected to a secondary battery and microbial fuel cells was developed and systematically optimized via an electrochemical performance test. According to standardized bio-dosimetry, the generated ultraviolet intensity powered by a pre-charged battery was determined to be 2.3×10-1 μW cm-2. The quantified UV intensity was used in calculating the fundamental kinetic parameters for the inactivation of microbial entities and the degradation of organic pollutants during UVC-LED and UVC-LED/H2O2 treatment processes. The fluence-based first-order rate constants were 1.07 and 2.43 cm2/mJ for Escherichia coli and 0.10 and 0.18 cm2/mJ for MS-2 bacteriophage, respectively. The study detected 2.76–8.00×10−16 M hydroxyl radicals at steady-state during UVC-LED/H2O2 treatment with 0.3–1mM H2O2. The second-order rate constant for atrazine during UVC-LED/H2O2 treatment was 1.90×109M−1 s−1 according to linear regression analysis of atrazine elimination over •OH exposure. This comprehensive investigation expands the application of microbial electrochemical systems in water treatment, providing a fundamental kinetic dataset for quantifying and predicting the microbial and (persistent) organic pollutants abatement.

Juno Observations Set New Constraints on the Electrodynamic Interaction Between Io and Jupiter.

Juno's highly elliptical polar orbits provide unprecedented in-situ observations of the electrodynamic interaction between Jupiter and its volcanic moon Io. These observations occur in regions never sampled before both near Io's orbit and near Jupiter's ionosphere and at distances between the two. Magnetic field data obtained during multiple traversals of magnetic field lines mapping to Io's orbit reveal remarkably rich and complex magnetic signatures near flux tubes connected to Io's orbital position. Here we present a methodology to model the distribution of currents along Io's flux tube (IFT) and Alfvén wings in such a way as to match the magnetic field signature observed during Juno's traversals of the IFT and Alfvén wings downstream of Io. We obtain the location, size and morphology of the current-carrying region as well as the distribution of currents within the IFT and Alfvén wings. The observed field-aligned currents exhibit strong filamentation, with upward and downward currents splitting into secondary cells rather than forming uniform structures. Additionally, there is a strong correlation between total field-aligned current intensity, particle energy flux, and Poynting flux, indicating efficient energy transfer and coupling in the Jupiter-Io system. Using all of Juno's traversals up to perijove (PJ) pass 42, we estimate the strength of the interaction with regards to distance along Io's extended tail, Io's position in the plasma torus and the magnetic field intensity at the footprint in Jupiter's ionosphere, illuminating the interaction of Jovian magnetospheric plasma with Io and setting important constraints in the Io-Jupiter interaction.

Improving both energetic and kinetic performances of osmotic battery for grid energy storage

Osmotic battery (OB), alternating the operation of reverse osmosis (RO) for charging and pressure-retarded osmosis (PRO) for discharging, is an emerging grid-scale energy storage system (ESS) that offers complementary advantages over other existing grid ESSs. OB utilizes osmotic pressure difference of two solutions as a media for energy storage. However, OB faces the issue of energetic-kinetic trade-off generally applicable in all the ESSs. This study aims to quantitatively analyze this trade-off in OB and to develop effective strategies to address this issue. Our analyses suggest that this trade-off can be addressed by (1) raising the initial high-salinity solution concentration (cHS,0), and (2) using more water permeable osmotic membranes with a suitable high-salinity solution. For example, increasing the cHS,0 from 1.2 M to 2.4 M increases energy density from 0.5 to >1.0 kWh·m−3 along with an enhanced power density and a stable high roundtrip efficiency (RTE) above 66 %, albeit requiring membranes with substantially improved mechanical strength. Furthermore, using high-permeance nanofiltration-type osmotic membranes with divalent high-salinity solution could improve the peak power density to above 50 W·m−2 while maintaining energetic performance. This study not only offers effective strategies to ease the energetic-kinetic trade-off but also recommends important directions for developing future osmotic membranes for OB.