Electrolyte System Research Articles

NiO/MnO2 coated on carbon felt as an electrode material for supercapacitor applications

Transition metal oxides have demonstrated excellent capability for charge storage when used in supercapacitor electrodes. This study undertook the hydrothermal synthesis of bimetallic nickel and manganese oxide (NiO/MnO2) on a carbon-felt (CF) substrate. NiO/MnO2/CF electrode was characterized and examined in a three-electrode system in a potassium hydroxide electrolyte. Cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge-discharge analyses revealed Faradaic behavior during charge storage, a specific capacity of 1627 F g-1, and a stability of 96.8% after 5000 consecutive charge-discharge cycles. Subsequent investigations were conducted in a two-electrode system for constructing a symmetrical supercapacitor using the NiO/MnO2/CF electrode. The energy and power densities were determined as 43Wh kg-1and 559 W kg-1. Additionally, the stability of the constructed supercapacitor device was examined over 5000 consecutive cycles, verifying a 92% stability through charge-discharge cycles. Finally, the fabricated supercapacitor was utilized to power an LED lamp, successfully maintaining the illumination for 53 s.

A near-single-ion conducting polymer-in-ceramic electrolyte for solid-state lithium metal batteries with superior cycle stability and rate capability

Composite solid-state electrolytes (CSE) represent a promising alternative to conventional porous separators and organic liquid electrolyte systems in commercialized lithium metal battery (LMBs), offering effective dendrite suppression, high interfacial compatibility and enhanced cycle life. This study introduces a polymer-in-ceramic electrolyte, which is synthesized by blending perovskite-type inorganic electrolyte Li1.5La1.5TeO6 (LLTeO) with polymethyl methacrylate (PMMA) and polyvinylidene fluoride (PVDF), denoted as PMMA/PVDF-LLTeO. The resulting CSE features a dense, non-porous structure, high mechanical strength, excellent thermal stability, and a broad electrochemical window. Notably, with the incorporation of a high ceramic filler content (up to 70 %), the CSE promotes a hybrid ion transport mechanism, yielding a near-single-ion conducting behavior with an ion transference number of 0.833, and a high elastic modulus of approximately 1 GPa. These attributes collectively contribute to the suppression of dendrite growth, as analyzed through multiphysics-based simulations. Li//Li symmetric cells using PMMA/PVDF-LLTeO-70 exhibit robust lithium stripping-plating stability, with a critical current density of 0.45 mA cm−2. Furthermore, the corresponding Li//LiFePO4 cells exhibit superior rate performance and cyclic stability, achieving over 150 cycles with a capacity retention rate of 92.2 % at high temperatures (60 °C). This research highlights the potential of the proposed CSE with high-temperature applications, significantly improving the safety and performance of LMBs

Quantitative Analysis of Complex Aluminum Electrolytes by X-Ray Fluorescence.

The future production of electrolytic aluminum will be characterized by low temperature, low carbon emissions, and environmental friendliness, which will result in a more complex electrolyte system. Real-time analysis of electrolytes can significantly enhance the efficiency of the electrolytic process. However, accurately analyzing the composition of complex aluminum electrolytes online has been a technical challenge. This research primarily focuses on determining the ingredient contents of complex aluminum electrolytes based on elemental concentrations measured using X-ray fluorescence (XRF) according to an applicable standard. Calibration curves were established based on 53 standard samples of complex aluminum electrolytes to establish relationships between XRF fluorescence intensity and real concentrations. Analysis conducted on industrial complex electrolytes confirms that these newly constructed curves effectively reduce relative errors to less than 3%. Additionally, a feasible solution is proposed for determining the cryolite ratio (CR) in aluminum electrolytes using XRF. Results demonstrate an average deviation as low as approximately 0.02, fully meeting industrial production requirements. This technique offers numerous benefits including rapid analysis, ease of use, and cost savings.

Adsorption of Imidazolium‐Based Ionic Liquid On Pt(111) Surface Studied Using Density Functional Theory

AbstractThe strength and nature of adsorption of imidazolium‐based tetraflouroborate ionic liquid (IL) on platinum surface has been investigated via first principle‐based density functional theory method. Adsorption of both IL cation and IL ion‐pair as a function of increasing alkyl chain length is taken into consideration. Three different orientations of ionic liquid cations are found to be stable with higher adsorption energy noticed for the alkyl chain parallel to the platinum surface. The anions are found to stabilize the IL cation orientation where the alkyl chain is oriented perpendicular the platinum surface. These results are further corroborated by the charge transfer analysis and electron density difference maps. The significant charge transfer between the ionic liquid pair and the surface indicates electrochemical applications for systems involving electrolytes and metal surface, where electrostatic interactions play a major role. The results of this investigation can be helpful for further analysis of electrode–electrolyte systems as well as the development of force field parameters for these systems.

Multipoint Anionic Bridge: Asymmetric Solvation Structure Improves the Stability of Lithium-Ion Batteries.

In this study, a novel concept of multipoint anionic bridge (MAB) is proposed and proved, which utilizes anions with different sites to connect with the asymmetric solvation structure (ASS). Compared to usual solvation structures, this study utilizes the multifunctional groups of difluoro(oxalate)borate anion (ODFB-), which can connect with Li+. By tailoring the concentration, the anion serves as a bridge between different solvated structures. The electrolyte is investigated through in situ techniques and simulations to draw correlations between different solvation structures and reaction pathways. The proposed design demonstrates remarkable high-temperature performance on both the anode and cathode sides, enabling stable cycling of LCO||graphite (0.5 Ah, 1.0 C) pouch cell for over 200 cycles at 80°C and facilitating Li||MCMB and Li||LFP cells to deliver stable performance for 200 cycles at 100°C. This work paves the way for the development of high-performance electrolyte systems by designing and using new multipoint anions to construct ASSs.

Unlocking Molecular Interactions of Biredox Eutectic Electrolyte for Non‐Aqueous Symmetrical Organic Redox Flow Batteries

AbstractBiredox deep‐eutectic solvents (DESs)‐based electrolytes have shown unique features in non‐aqueous asymmetrical redox flow batteries (RFBs) that can potentially mitigate the crossover issue. However, strong intermolecular interactions among the electrolyte constituents in DESs bring in practical challenges such as limited mass transfer rates, slow redox kinetics, and degraded cyclability. Here, by using a novel biredox‐type DES based on 4‐methoxy‐2,2,6,6‐tetramethyl‐1‐piperidinyloxy (4‐MeO‐TEMPO) and 3,3′‐dimethylazobenzene (3,3′‐Azo) as a model electrolyte system, the intermolecular interaction involving in the biredox DESs is unlocked by first‐principles calculations, and their influence on the electrochemical performance of biredox DESs couples is systematically investigated in comprehensive consideration of the solvents and the supporting salts. It demonstrates that employing tetrabutylammonium bis‐trifluoromethane sulfonimidate‐acetonitrile as the supporting electrolyte synergistically weakens the intermolecular interactions within the DESs, thereby significantly promoting the redox kinetics and electrochemical reversibility in non‐aqueous symmetrical RBFs. With such an optimized electrolyte, a prototype symmetrical cell under static mode is capable of delivering a high output voltage of ∼2.15 V, a decent cyclability, and the exceptional rate capability with a current density of 25 mA cm−2. This study provides a simple yet effective way to develop advanced RFBs with dependable electrolyte regulation.

Effect of glycerin on the physical properties of polyvinyl alcohol/sodium alginate blend

Because of the abundance of sodium resources, sodium-ion batteries (NIBs) offer a promising alternative electrochemical energy storage solution. One of the current roadblocks to the development of NIBs technology is a lack of electrode materials capable of reversibly storing/releasing sodium ions for a sufficiently long time. Thus, this work aims to study, theoretically, the effect of glycerin incorporation on polyvinyl alcohol (PVA)/sodium alginate (Na Alg) blend as electrode materials for NIBs. The electronic, thermal, and quantitative structure-activity relationship (QSAR) descriptors of polymer electrolytes based on a blend of PVA and Na Alg and glycerin are the main topics of this work. These properties are examined here using semi-empirical methods and the density functional theory (DFT). Bandgap energy (Eg) is examined because the structural analysis reveals details regarding the interactions between PVA/Na Alg and glycerin. The findings indicate that the addition of glycerin caused the Eg value to drop to 0.2814 eV. The molecular electrostatic potential surface, or MESP, shows the electron-rich and deficit regions throughout the electrolyte system as well as the distribution of molecular charges. Thermal parameters that are studied include enthalpy (H), entropy (ΔS), heat capacity (Cp), Gibbs’ free energy (G), and heat of formation. Additionally, the study examines several QSAR descriptors, such as total dipole moment (TDM), total energy (E), ionization potential (IP), Log P, and Polarizability. The results show that H, ΔS, Cp, G, and TDM increased with increasing temperature and glycerin content. Meanwhile, heat of formation, IP, and E decreased, improving reactivity and polarizability. Additionally, the cell voltage increased to 2.488 V due to glycerin addition. The overall DFT and PM6 calculations of cost-effective PVA/Na Alg based glycerin electrolytes indicate that they can partially replace lithium-ion batteries due to their multifunctionality, but requires further improvement and investigations.

A review of recent developments in the design of electrolytes and solid electrolyte interphase for lithium metal batteries

AbstractLithium metal batteries offer a promising solution for high density energy storage due to their high theoretical capacity and negative electrochemical potential. However, implementing of these batteries faces challenges related to electrolyte instability and the formation of a solid electrolyte interphase (SEI) on the lithium (Li) metal anode. The decomposition of liquid electrolytes leading to the creation of the SEI emphasizes the significance of the type of Li salt, solvent, and additives designed and used, as well as their interactions during the formation of the SEI. For practical applications, ensuring both the reversibility of the Li metal anode and electrolyte stability at high voltages is crucial. In this review, we explore recent advancements in addressing these challenges through new designs of electrolytes and SEI engineering practices. Specifically, we investigate the effects of electrolyte systems, including carbonate‐based and ether‐based solutions, along with modifications to these electrolyte systems aimed at achieving a more stable interface with the Li metal anode. Additionally, we discuss various artificial SEI structures based on organic and inorganic components. By critically examining recent research in these areas, this review provides valuable insights into current state‐of‐the‐art strategies for enhancing the performance and safety of Li metal batteries.image

Dielectric additive induced weak Li solvation towards stabilized solid electrolyte interface for 4.6V lithium metal batteries

Developing stable electrode-electrolyte interphases on Li metal anode (LMA) and high voltage cathode is crucial for producing durable Li metal batteries. Electrolyte engineering has been regarded as an efficient way to in-situ construct stable and robust interphase. Herein, a dielectric electrolyte system is proposed by introducing LiNbO3 nanoparticles to liquid carbonate-based electrolyte for regulating Li+ solvation structure, and thus inducing stable inorganic-rich solid electrolyte interphase. Moreover, these dielectric nano LiNbO3 additives can regulate the Li+ flux through their build-in electric field to guide dendrite free Li deposition. These multi-functional features of LiNbO3 allow for exceptional cyclic performance in both symmetric cell configuration (3300 h at 0.5 mA cm−2 and 1 mA h cm−2) and Li||LiNi0.8Co0.1Mn0.1O2 half-cell charged at 4.6 V with capacity retention of 80% over 200 cycles. These results demonstrate great potential of dielectric electrolyte on improving the performance of lithium metal batteries.

Tuning the Solvation Structure of a Weakly Solvating Cyclic Ether Electrolyte for Wide‐Temperature Cycling of Lithium‐Sulfurized Polyacrylonitrile Batteries

AbstractSulfurized polyacrylonitrile (SPAN) cathodes in high energy‐density Li‐metal batteries have garnered widespread interest owing to their good cycling stability and moderately high capacities. However, their application is hindered by the low prevalence of advanced electrolytes that can simultaneously mitigate polysulfide generation at the cathode and stabilize the Li‐metal anode. Here, a weakly solvating electrolyte is presented, employing a single solvent tetrahydropyran (THP). The solvation structure is effectively tuned by adjusting the salt concentration to stabilize both the Li‐metal anode and SPAN cathode. This approach enables stable cycling with high SPAN loadings (≈5 mg cm−2) and lean electrolyte contents (≈5 µL mgSPAN−1) across a wide temperature range: 0 °C, room temperature, and 50 °C. A pouch cell with a high SPAN loading and a low electrolyte‐to‐SPAN (E/SPAN) ratio of 3 µL mg−1 shows a stable 79.1% capacity retention after 40 cycles. Additionally, THP can be effectively employed in localized high‐concentration electrolyte (LHCE) systems to reduce the diluent‐to‐solvent ratio for greater LHCE viability. The study demonstrates the potential of weakly solvating solvents in Li‐SPAN batteries, offering a pathway for their practical application.

Ternary-salt localized high-concentration electrolyte: An ideal companion facilitating stable high-voltage cycling of lithium metal batteries

The strategic design of novel electrolytes to further enhance the overall performance of lithium metal batteries (LMBs) is highly desirable. Herein, combining the synergistic effect of multiple functional lithium (Li) salts and the solvation structure advantage of localized high-concentration electrolyte (LHCE), we propose a novel ternary-salt localized high-concentration electrolyte (TSLHCE) termed CETHER3-TDE that achieves broad electrochemical stability window, dendrite-free Li deposition, effective electrode interface protection, flame retardancy, and significantly enhances the cycling performance of LMBs. CETHER3-TDE enables Li (50 μm thickness) ||NMC622 (13.8 mg cm−2, 2.50 mAh cm−2) cell to achieve an impressive capacity retention of 83 % after 300 cycles with a cut-off voltage of 4.4 V. Additionally, it enables the Li (50 μm thickness) ||NMC811 (19.8 mg cm−2, 3.96 mAh cm−2) cell to achieve a capacity retention of 83.6 % after 170 cycles, under an ultrahigh cut-off voltage of 4.6 V. Furthermore, the Li metal pouch cell employing CETHER3-TDE, featuring a low negative/positive (N/P) capacity ratio of 1.33 and lean electrolytes of 2.3gAh−1, attains an energy density of 413 Wh kg−1 and maintains stable cycling at 4.6 V. Moreover, analysis conducted by Accelerating Rate Calorimeter has verified that CETHER3-TDE enhances both the thermal stability as well as the thermal runaway trigger temperature of LMBs, thereby substantially improving their safety. This work provides valuable insights for future research on multi-salt complex electrolyte system for practical application in high-energy-density and high safety LMBs.

Investigation of modified deep eutectic solvent for high performance vanadium redox flow battery

Amidst the growing need for sustainable energy solutions, the vanadium redox flow battery (VRFB) emerges as a promising technology for large-scale grid energy storage. Compared to conventional aqueous electrolyte system, deep eutectic solvents (DES) have the potential to be considered as the smart electrolyte system for VRFB, owing to its exceptional features such as broad electrochemical window, facile synthesis, low vapor pressure, and economically viable. Unfortunately, original DES have inherently low ionic conductivity and high viscosity, limiting their applicability in flow batteries. To address this issue, we propose deep eutectic solvent (DES)-based vanadium electrolytes containing an optimal amount of aqueous acid and dispersed sulfonated multi-walled carbon nanotubes (sMWCNT) in a 1:6 choline chloride:ethylene glycol mixture (Eu-sMWCNT VIII/VIV) and in detail, evaluate the performance of a single-cell VRFB using this electrolyte. In this work, it is demonstrated that DES electrolyte can be made more conducting and less viscous with subtle modifications. The prepared electrolyte exhibits excellent electrochemical properties, showcasing high-capacity retention (90.0 % over 400 charge/discharge cycles at an applied current density of 30 mA cm-2) and efficiencies (average Coulombic and energy efficiencies of 84.0 % and 70.0 % over 400 cycles, respectively). This modified DES system holds potential as the future electrolyte for various flow battery technologies, enabling operation at higher applied current densities compared to reported DES-based flow batteries.

Turn the dust into glory: Hierarchical porous carbon cubes derived from waste tire pyrolysis oil exhibits high capability in symmetric capacitors

Fabricating suitable porous carbon materials that are simultaneously applied in various electrochemical energy storage (EES) systems including supercapacitors (SCs) and lithium-ion capacitors (LICs) has an important significance in meeting the increasing demands in high energy density, high power density along with ultra-long life. Herein, cubic hierarchical porous carbon (CHPC) with abundant micro-mesoporous structures and moderate S, N co-doped atoms has been rationally designed by using MgO cubes as the templates and waste tire pyrolysis oil (WTPO) as carbon source and dopant. Attributed to the unique microstructures, the CHPC materials have been successfully utilized in different EES systems. In the aqueous electrolyte system, the assembled CHPC-2//CHPC-2 with 2 mg cm−2 delivered high specific capacitance of 199.0 at 1 A/g, along with 98.5 % capacity retention rate for 20,000 cycles at 6 A/g. Even at high mass loading of 12 mg cm−2, CHPC-12//CHPC-12 still can deliver high gravimetric and areal capacitances of 187.0 F g−1 and 2.24 F cm−2 at 10 A/g, showing an excellent high-loading performance. Even under extreme conditions of −40 and 60 °C, the assembled SCs still can deliver an ultrahigh capacity retention rate of 97.9 % and 100 % at 10 A/g for 2000 and 8000 cycles, respectively. In addition, the symmetric CHPC//CHPC LICs also have been assembled and displayed a maximal energy density of 133.5 Wh Kg−1 at 1178.2 W Kg−1. This work provides new insight into the high-value utilization of WTPO for prepared porous carbon with excellent electrochemical performance in various EES systems.

Synergistic Dual Electrolyte System of LATP and In‐ Situ Solod‐State PDOL System and its Improvement on the Performance of NCM811 Batteries

Abstract1,3‐Dioxolane (DOL) can undergo in‐situ polymerization in batteries to form solid‐state organic electrolyte PDOL. When applied to NCM811||Li battery system, PDOL electrolyte helps optimize the contact and interface stability between electrolyte and electrodes. This study explores the effects of PDOL with PE separators coated with Li1.3Al0.3Ti1.7(PO4)3(LATP) on the performance of NCM811||Li batteries. 2,2,2‐trifluoroethyl phosphite (DETFPi), was mixed with DOL at a 1 : 35 mass ratio. Then, LiBF4 was used to initiate in‐situ polymerization and thereby obtained DETFPi‐PDOL electrolyte after 24 h at room temperature. The composite electrolyte exhibits enhanced ion conductivity (1.59×10−4 S cm−1), high lithium ion transference number (0.78), wide electrochemical stability window (4.53 V), and high critical current density (2.2 mA cm−2). Li||PDOL@LATP||Li battery shows extremely low overpotential (35 mV) after a constant current stable cycle of 500 h at 1.0 mA cm−2. After 500 cycles at 1 C, the remaining capacity is 153.9 mAh g−1 with a capacity retention of 82.1 % in NCM811||PDOL@LATP||Li batteries. This indicates that the LATP coating on the surface of the PE separator plays an important role in optimizing the performance of DETFPI‐PDOL electrolyte batteries. LATP and DETFPI‐PDOL are effective in improving the cycling stability, rate performance, and interface state of NCM811 batteries.

Recyclability study for the next generation of cobalt-free lithium-ion battery systems with C-LNMO, Si/C- LRLO and TiNbO-LNMO active materials via hydrometallurgical route

The scarcity and uncertain supply of cobalt poses significant challenges for the lithium-ion battery industry. To address this issue, alternative chemistries excluding cobalt have been developed. Despite solving supply issues, these developments raise concerns about recyclability and their impact on current recycling trends.This study presents a recycling strategy and evaluates its performance for next-generation cobalt-free lithium-ion batteries. It focuses on three prototypes that use innovative cathode materials (titanium niobium oxide, carbon, and silicon/carbon) and electrolyte systems (ionic liquid and gelified). The proposed recycling process includes pyrolysis, mechanical separation, neutral and acid leaching, cementation, and neutralisation for selective metal separation.The results indicate that gelified electrolytes exhibit greater thermal stability than their liquid counterparts, indicating an effect on the degradation temperature and gas emissions, which are crucial for metal recovery. This study highlights the reduced toxicity of ionic liquid electrolytes and emphasises the need for strict pyrolysis gas handling due to hazardous emissions. High recovery rates (65–90 %) were achieved for nickel, manganese, lithium, and anode components.With potential for process optimisation to improve the quality of products, this study shows that cobalt-free battery systems can be integrated into existing recycling frameworks with adjustments, supporting progress towards sustainable battery practices.

Direct observation of sodium dendrites to decipher the complicated behavior of electrolyte systems

The compatibility of the electrolyte system with the metal anode, which is often overlooked, is pivotal in realizing the development of a long-life battery. In the present contribution, the compatibility of the diglyme-based electrolyte systems with the sodium metal anode is examined and found that the solvation structure of the electrolyte plays a central role in controlling the sodium deposition morphology. The localized Raman and 1H NMR spectroscopy reveals that the solvation structure for ClO4—, PF6—, and CF3SO3— is distinct and differs from each other. While a loose solvation structure is observed for ClO4—, CF3SO3— based electrolytes exhibit a compact solvation structure. In-situ optical microscopy provides real-time information about the sodium deposition morphology, varying from needle-, tree- and moose-like morphology in ClO4—, PF6—, and CF3SO3— based electrolytes, respectively. The Coulombic efficiency (Na//Cu) and stripping/plating overpotential of sodium (Na//Na) are also sensitive to the structure of the solvation shell. In addition, the post-cycle XPS analysis suggests that the CF3SO3— based electrolytes lead to the formation of an inorganic-rich SEI. This comprehensive study underscores the importance of electrolyte composition in achieving stable sodium metal anodes, providing valuable insights for the development of high-performance sodium metal batteries.

Revealing Energy Density in Porous Carbon Supercapacitors Using Hydroquinone Sulfonic Acid as Cathodic and Alizarin Red S as Anodic Redox Electrolytes.

Exploration of innovative strategies aiming to boost energy densities of supercapacitors without sacrificing the power density and long-term stability is of great importance. Herein, highly porous nitrogen-doped carbon spheres (NPCS) are decorated onto the graphite sheets (GSs) through a hydrothermal route, followed by a chemical activation. The capacitive performance of the NPCS is then enhanced by hydroquinone sulfonic acid (HSQA) incorporation in both cathodic electrolyte and electrode materials. Later, NPCS are decorated with polypyrrole (PPY), in which HSQA takes a versatile role as conjugated polymer dopant and cathodic redox additive. The capacitive performance of the negative electrodes is enhanced by incorporating of alizarin red S (ARS) as anodic redox additive. Finally, PPY(HQSA)@NPCS-GS//NPCS-GS asymmetric supercapacitor is assembled and tested in dual redox electrolyte system containing HQSA-cathodic and ARS-anodic electrolytes. This device delivers a remarkable energy density of 60.37 Wh kg-1, which is close or even better than lead acid batteries. Thus, the present work provides a novel pathway to develop high energy supercapacitors using redox active electrolytes for next-generation energy storage applications.

Zinc Chemistries of Hybrid Electrolytes in Zinc Metal Batteries: From Solvent Structure to Interfaces.

Along with the booming research on zinc metal batteries (ZMBs) in recent years, operational issues originated from inferior interfacial reversibility have become inevitable. Presently, single-component electrolytes represented by aqueous solution, "water-in-salt," solid, eutectic, ionic liquids, hydrogel, or organic solvent system are hard to undertake independently the task of guiding the practical application of ZMBs due to their specific limitations. The hybrid electrolytes modulate microscopic interaction mode between Zn2+ and other ions/molecules, integrating vantage of respective electrolyte systems. They even demonstrate original Zn2+ mobility pattern or interfacial chemistries mechanism distinct from single-component electrolytes, providing considerable opportunities for solving electromigration and interfacial problems in ZMBs. Therefore, it is urgent to comprehensively summarize the zinc chemistries principles, characteristics, and applications of various hybrid electrolytes employed in ZMBs. This review begins with elucidating the chemical bonding mode of Zn2+ and interfacial physicochemical theory, and then systematically elaborates the microscopic solvent structure, Zn2+ migration forms, physicochemical properties, and the zinc chemistries mechanisms at the anode/cathode interfaces in each type of hybrid electrolytes. Among of which, the scotoma and amelioration strategies for the current hybrid electrolytes are actively exposited, expecting to provide referenceable insights for further progress of future high-quality ZMBs.

PEG-based co-solvent aqueous electrolytes enabling high-energy rechargeable aqueous magnesium-ion batteries

In contrast to organic electrolyte systems, rechargeable aqueous magnesium-ion batteries (RAMIBs) offer unparalleled advantages, particularly in environmental sustainability, safety, cost-effectiveness, and their potential for large-scale energy storage. However, the practical implementation of RAMIBs has been hindered by the limited electrochemical stability of aqueous electrolytes. Although polyethylene glycol (PEG)-based aqueous electrolytes provide a wide electrochemical window, the poor ionic conductivity has restricted their widespread adoption. In this study, we address this challenge by employing trimethyl phosphate (TMP) and PEG400 as the co-solvent of aqueous magnesium-ion electrolytes. This combination significantly enhances the ionic conductivity to 4.44 mS cm−1 and increases the electrochemical stability window of the aqueous electrolyte by mitigating the activity of H2O. In addition, we underscore the role of TMP as a potent co-solvent in modulating the solvation structures of Mg2+ ions and modifying the electrochemical behavior of the electrolytes. Leveraging this advancement, in conjunction with a V2O5 cathode and a 3,4,9,10-perylenetetracarboxylic diimide (PTCDI) anode, the resulting RAMIBs demonstrate a remarkable discharge capacity of 227.6 mAh g−1, a large energy density of 157 Wh kg−1 and a high power density of 70 W kg−1. Our findings represent a significant stride toward exploiting the full potential of RAMIBs for future energy storage applications.

Electrochemical performance enhancement of perovskite-type Li0.3La0.57TiO3 ceramic electrolyte by controlling synthesis parameters

This study investigates the enhancement of the electrochemical performance of perovskite-type Li0.3La0.57TiO3 (LLTO) solid electrolytes through the optimization of synthesis parameters of a sol-gel process. The primary focus lies in examining the impact of calcination temperature on the structural, morphological, and electrochemical properties of LLTO. Our findings reveal that controlling the calcination temperature significantly influences the grain boundary resistance and overall ionic conductivity. The optimal calcination temperature was identified to be 800 °C, yielding a remarkable improvement in ionic conductivity at grain boundaries (0.88 mS/cm), and total ionic conductivity (0.54 mS/cm), at 30 °C. This enhancement is attributed to the refined microstructure, increased density, and reduced porosity, which collectively facilitate lithium-ion diffusion. These advancements in LLTO electrolytes present promising implications for their application in all-solid-state lithium-ion batteries, offering a safer and more efficient alternative to conventional liquid electrolyte systems.