Journal of The Electrochemical Society

Molten salts are of particular interest for a variety of industrial applications. As such, accurate characterization of species’ concentrations within the molten salt media is critical to ensure a well-controlled unit operation. Although electroanalytical tools are properly suited for precise in situ monitoring in these systems, uncompensated ohmic resistance RΩ can lead to erroneous, technique-dependent results. Using numerical simulations applied to a model system, this work will first illustrate then quantify the extent to which RΩ attenuates square wave voltammograms. This approach allows for post-experiment correction that leads to converging results across voltammetric techniques and facilitates accurate predictions of species’ concentrations.

Low concentration detection and analysis of dissolved characteristic gas Acetylene (C2H2) in oil is one of the effective methods for power transformer condition maintenance to ensure safety. The MEMS gas sensor based on the nanostructured material has become a research hotpot for detecting the C2H2. In this work, SnO2 and NiO thin films were successively deposited by RF sputtering, followed by annealing at different temperatures to prepare NiO/SnO2 heterostructures, and the C2H2 sensor chips were prepared by MEMS (microelectromechanical systems) compatible process by using the SnO2/NiO thin films as sensitive materials. The results showed that the detection limit of the MEMS sensor based on the NiO/SnO2 (NiO/SnO2-2) film annealed at 450 °C was as low as 0.2 × 10⁻⁶ toward C2H2. The sensor exhibits a high response at 260 °C (S = 7.9 toward 1.4 × 10⁻⁶ C2H2), which is about 4.5 times that of pure SnO2(1.8). Meanwhile, it has an extremely short response time (13 s and 19 s). This study reveals that dissolved acetylene gas in transformer oil can be detected more efficiently by the sensor with nanostructured heterojunctions as sensitive materials.

This work underlines the modification and effect of iron doping on different characteristics of NiO nanoparticles. The facile hydrothermal method was followed to form pristine and iron doped (4% and 8%) NiO sample. The X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), transmission electron microscopy (TEM), UV–Vis spectroscopy and Raman spectroscopy techniques were employed for the identification of phase, morphology, microstructural details and optical property of the as synthesized Fe doped NiO samples. XRD measurements of the as synthesized Fe doped NiO samples revealed the polycrystalline nature with the crystallite size varying from 11 nm–20 nm showing hexagonal structure. Surface morphology investigation carried out by using SEM showed the varied morphology of as synthesized samples. UV–vis investigation revealed a red shift with increasing iron doping content, which corresponds to a decrease in optical bandgap values from 3.4 eV for pure NiO to 2.2 eV for 8% Fe doped NiO sample thus giving a wide tuneable absorption bandgap. The study of cyclovoltammetry and PEIS demonstrates the novelty of this work showing exceptionally high electrochemical performance in a three-electrode system with highest specific capacitance of 977 F g⁻¹ at scan rate of 20 mV sec⁻¹ for 8% doped sample.Vibrating sample magnetometry (VSM) measurement shows good ferromagnetic behaviour with high coercivity for iron doped NiO sample making it a useful MRI agent. The results demonstrate as synthesised iron doped NiO nanoparticles as viable material for supercapacitor applications.

Poly(aniline-co-o-toluidine) (PANI-POT) copolymer represents a significant advancement in the field of conjugated copolymers, providing enhanced electrochemical performance in neutral media. However, the incorporation of inorganic species into copolymer matrices has the potential to further increase electroactivity. For this reason, the electrochemical synthesis of PANI-POT copolymers was conducted in the presence of Ni, Mo and W elements on indium tin oxide (ITO) substrate. Examination of the resulting composite films revealed new electrochemical and morphological characteristics, such as reversible behavior, a shift in the oxidation peak and smoother, more rigid surfaces. Despite these improvements, the electroactivity of the composite films was reduced compared to the pure copolymer, as indicated by the anodic charge densities of 1.84 mC cm⁻² for PANI-POT, 0.2 mC s⁻¹ for PANI-POT/NiMoW, 0.23 mC cm⁻² for PANI-POT/NiW, 0.30 mC cm⁻² for PANI-POT/NiMo and 0.96 mC cm⁻² for PANI-POT/MoO2. This study explored the factors responsible for reduction in electrochemical performance of the copolymer upon the incorporation of Ni, Mo and W, despite the favorable electrochemical properties of these elements, and discussed the potential applications of the new electrochemical and physical characteristics, such as protective coating.

Li-ion batteries are commonly used as electrochemical energy storage systems due to their high energy density. However, few Li-ion batteries can reliably function at elevated temperatures, which is necessary for space and defense applications. In this study, Li-ion electrolytes were prepared and investigated for use at 100°C. The previously developed baseline electrolyte, 1.0 M lithium hexafluorophosphate (LiPF6) in 1:1 ethylene carbonate (EC):ethyl-methyl carbonate (v/v) with 2 wt. % vinylene carbonate (VC), was altered to observe the effects of the lithium salts lithium difluoro(oxalato)borate (LiDFOB) and lithium difluorophosphate (LiDFP), and the fluorinated co-solvent 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TTE). The resulting formulations showed significantly improved capacity retention at 100°C in multiple cell configurations. X-ray photoelectron spectroscopy characterization of the electrodes following cycling at high temperatures with the improved electrolyte revealed the cathode-electrolyte-interface to be boron-rich, while the graphite anodes were found to have little boron but were more fluorine rich compared to the baseline anodes. Raman spectroscopy determined notable changes in solvation structure upon addition of the TTE diluent. Overall, the use of various Li salts as well as the TTE co-solvent improved specific capacity retention at 100°C in Li-ion cells.

Platinum and palladium are the most suitable electrode materials for studying the kinetics and mechanism of various electrochemical processes. Consequently, their behavior in electrochemical systems has been the subject of extensive study. However, the effect of pulse alternating current (PAC) on Pt and Pd in aqueous electrolytes represents a relatively new area of research for electrochemical process technologies. It was demonstrated that employing PAC with a frequency of 50 Hz to platinum in NaOH electrolyte result in the formation of Pt particles (7.6 nm) containing a PtOx phase (0.25±0.03 wt.%). The dissolution of platinum in NaCl electrolyte resulted in the formation of only platinum chloride complexes. The palladium in the NaOH electrolyte was passivated when PAC was employing to Pd electrodes. In the NaCl electrolyte, the formation of Pd-PdO particles (42±2 wt.% of PdO) was observed. The crystallite size for Pd and PdO was 7.9 and 1.99 nm, respectively. The discrepancy in the chemical properties of two metals belonging to the transition metals of group VIII of the periodic system, which are characterized by the same space group (Fm3m), can be attributed to the combination of electronic and redox properties of Pt and Pd.

This work analyzes the detection of carbamazepine (CBZ), a commonly used pharmaceutical that exhibits extended persistence in aquatic habitats, by the application of advanced sensor technologies. Owing to its chemical stability, CBZ is resistant to natural degradation, posing significant ecological risks in aquatic environments. Conventional techniques for CBZ detection, such as high-performance liquid chromatography and spectrophotometry, require intricate laboratory configurations and significant sample preparation, restricting their use for fast in situ monitoring. To tackle these issues, we created a portable electrochemical sensor using screen-printed electrodes on a flexible polyester-based substrate. Under optimized conditions, the sensor demonstrated high sensitivity in a linear detection range from 1 to 20 µM with a detection limit of 0.8 M by differential pulse voltammetry technique. Recovery range was found to be 93% to 107%, which further confirmed reliability, showing consistency in CBZ detection across varied concentration levels in wastewater. Preliminary results on continuous measurements have been carried out, demonstrating a promising application for prolonged analysis in real-settings.

Pаtulin is а mycotoxin synthеsizеd by Pеnicillium, Byssochlаmys, аnd Аspеrgillus gеnеrа especially in wаtеr аnd sugаr-rich fruits such аs аpplеs аnd grаpеs, аs wеll аs in sеаfood, tomаtoеs, аnd cеrеаls. Due to its high toxicity for humans, it is essential to have on-site screening methods for fruits, vegetables, seafood and their processing products like apple juice. Therefore, a disposable textile sensor based on combined diamond like carbon – Ag nanolayer which was modified with two porphyrins: Zinc-protoporphyrin IX (znpp-IX), and 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphine Manganese(III)chloride (mnoep) to give two different 2D sensors were designed. The 2D sensors were used for the on-site assay of patulin in different types of apple juices. The wide working concentration ranges allow the reliable assay of patulin from 1 amol l⁻¹ to 1 mmol l⁻¹ and with high sensitivities (up to 1 × 10¹¹ s⁻¹mol⁻¹l) and with limits of quantificationup to 0.10 pmol l⁻¹. Recoveries higher than 95.00% with relative standard deviation lower than 1.00% were recorded for the assay of patulin in apple juice.

The two-electron oxygen reduction reaction (ORR) using an electrochemical method is considered a viable green technology for generating H2O2. Platinum group metals demonstrate excellent H2O2 generation performance due to their superior ORR activity and stability. However, the high cost of these electrocatalysts is a significant barrier to the widespread adoption of this technology, prompting research into non-precious metal catalysts as alternatives. In this work, Co3O4 nanoparticles with sized from 5 to 10 nm were synthesized on MXene sheets. Compared with Co3O4/C and MXene, the results indicated that Co3O4/MXene exhibited the best electrochemical performances, with an electron transfer number of ∼3.1 during oxygen reduction and an H2O2 selectivity of ∼47%. Co3O4/MXene also demonstrated great stability. After 5000 cycles, the H2O2 selectivity and electron transfer number remained at 50% and 3.0, respectively. After 12 h of continuous testing, Co3O4/MXene exhibited a high Faraday efficiency of 50% and H2O2 yield of 0.14 mol h⁻¹ g⁻¹, with H2O2 selectivity increasing to 68.7% and an electron transfer number of 2.6. The excellent electrochemistry is attributed to the synergistic effect between MXene and Co3O4. This study provides valuable insights into non-precious metal electrocatalysts for H2O2 generation.

Vanadium redox flow batteries (VRFBs) are a promising solution for integrating intermittent renewable energy sources into the existing power grid. However, enhancing the electrochemical performance of VRFBs is critical for their widespread adoption in grid-scale energy storage. This study investigates the impact of adding a porous binder to a carbon-cloth electrode, with a focus on optimizing thermal activation conditions. The electrochemical performance of the binder-coated electrodes compared to uncoated electrodes is evaluated through electrochemical impedance spectroscopy, polarization curve measurements, and charge-discharge cycling. The surface morphology and structural integrity of the binder-coated electrodes at each activation stage are examined using various material characterization techniques to assess the effects of thermal activation. The results are benchmarked against the experiments using non-coated electrodes to determine the performance improvements offered by the binder coating. Notably, the study reveals that binder-coated electrodes exhibit significantly lower resistance and improved efficiency compared to their uncoated counterparts, with optimal activation conditions enhancing performance metrics crucial for VRFB applications. These findings provide valuable insights for further optimizing electrode design and activation strategies, advancing the development of more efficient VRFB systems for large-scale energy storage.

Lithium-ion batteries have a great potential in stationary energy storage, both for first- and second life, but the understanding and tools to evaluate cell degradation needs to be improved. In this study, the degradation of batteries subjected to three types of stationary services, as well as the repurposing of cells from more demanding to a milder application is investigated. The milder cycle is frequency regulation with a maximum C-rate of 1.5 C (FR1.5C) and the more demanding cycles peak shaving with a C-rate of 1 C (PS1C) and FR and PS combined (FRPS2C). The main driver for accelerated capacity loss was identified as the state-of-charge (SOC) change during operation, increasing the rate of degradation for PS and FRPS. The cell impedance was measured and fitted to a physics-based model to deconvolute the sources of polarization increase. A tortuosity increase in the negative electrode was seen for all cells, as well as a resistance increase. FRPS2C and PS1C further showed a decrease in the electrolyte mass transport properties. When repurposed to the milder FR1.5C application, PS1C showed a clear decrease in capacity loss rate while more heterogeneous degradation might be the reason for a higher rate of degradation for the repurposed FRPS2C cell.

The performance of Lithium-Sulfur (Li-S) batteries is significantly influenced by material selection and manufacturing processes, with conductive carbon and slurry formulation playing crucial roles. In this study, the impact of carbon morphology and solvent/solid ratio in slurry preparation on microstructure and electrochemical performance of sulfur cathodes was investigated. Various carbon structures, such as nanotubes, sheets, and particles, were explored, and the solvent volume was adjusted to assess their effects on electrode architecture and electrochemical performance. Our findings demonstrate that the binder dissolution process and consequent electrode architecture and performance are highly influenced by both the carbon structure and slurry solvent volume. Furthermore, it was observed that, contrary to common assumption, advanced carbon structures are not necessary for enhanced capacity and durability of Li-S cathodes. Accordingly, the best cycling durability was achieved by optimizing the slurry with 300 µL/mgPVDF of NMP solvent and using Ketjen black as the conductive carbon, resulting in an initial capacity of 1029 mAh/gS, with a retention of 830 mAh/gS after 500 cycles. These results, obtained at a high areal loading of 4.5 mgS/cm², demonstrate the commercial potential of the proposed electrode formulation and processing method without reliance on advanced materials or techniques.

A mesh-type assembly and stirrer assembly were developed to improve the performance of liquid cadmium cathodes for the electrodeposition of U and Ce from LiCl-KCl molten salt at 773 K. The thermodynamic basis for electrodepositing U and Ce was established through the calculation of equilibrium potentials and cyclic voltammograms, while also examining the co-deposition of Li. Thereafter, U and Ce electrodeposition was performed by galvanostatic electrolysis, and the current efficiency was determined. It was found that both assemblies effectively hampered the growth of U dendrites and Ce-Cd dendritic alloys. However, the utilization of the mesh-type assembly resulted in a greater current efficiency for U, with the maximum deposited amount attaining 7.7 wt% U/Cd without causing U dendrites formation. In contrast, the current efficiency for Ce was enhanced after using the stirrer assembly due to an improved diffusion flux of Ce ions. Finally, cathode deposits were characterized by scanning electron microscopy, energy-dispersive spectroscopy, and X-ray diffraction, which revealed that disrupted fine U dendrites were randomly scattered in the Cd bulk, and that the CeCd11 dendritic alloys were also damaged, leading to an increased atomic ratio of Ce to Cd at the Cd bottom.

Lithium has been widely investigated owing to its high theoretical specific capacity and low electrochemical potential. This is required for high-energy-density lithium batteries such as lithium–sulfur (Li–S) batteries. Recently, Li–S batteries with polysulfide-insoluble electrolytes, such as sulfolane (SL) and triglyme (G3), have attracted research attention because they suppress the dissolution of lithium polysulfide intermediates. However, lithium dendrite growth on the Li metal anode during the charging–discharging process causes an internal short-circuit, which may lead to serious accidents. To realize a Li–S battery, a fail-safe system to prevent short-circuits is essential. In this study, we investigated the cycle degradation mechanism of a Li metal anode in SL and G3 electrolytes using electrochemical impedance spectroscopy. The changes in charge transfer resistance (Rct) and solid electrolyte interphase resistance (RSEI) of Li-Li symmetrical cells in SL and G3 electrolytes was measured under charge–discharge cycling in detail down to internal short-circuits. Consequently, in both the electrolyte systems, the RSEI and Rct behaviors were disparate during cycling, and a mechanism for the short-circuit process was proposed. In addition, before the short-circuit process occurred, the change in the trend of Rct from stable to increasing was indicative of an imminent short-circuit.

Partial lithiation of silicon active materials for lithium-ion batteries recently gained attention as a promising mitigation strategy for the degradation phenomena associated with the severe volume expansion upon the lithiation, particularly in the case of large, microscale silicon particles. It was suggested that this is caused by the formation of a stabilizing core-shell-like particle structure in the first cycles, consisting of a crystalline core and amorphous silicon shell. In this study, we investigated the microstructure of partially lithiated microscale silicon particles using transmission electron microscopy (TEM). When observed via TEM, the contrast difference in amorphous and crystalline silicon is utilized to reveal previously lithiated areas inside the silicon microparticle. We investigated the influence of lower cutoff potentials and amorphization progress in half-cells. We also examined the changes over prolonged cycling in full-cells with an NCA cathode after 12 and 243 cycles. Silicon particle pulverization was not observed for any sample, even though we found that substantial parts of the particles' insides had been lithiated. We suggest that the diffusion of Li along grain boundaries and stacking faults plays an essential part in the amorphization and cycling of microscale Si particles but does not lead to their cracking or pulverization.

Simulation models are nowadays indispensable to efficiently assess or optimize novel battery cell concepts during the development process. Electro-chemo-mechano models are widely used to investigate solid-state batteries during cycling and allow the prediction of the dependence of design parameters like material properties, geometric properties, or operating conditions on output quantities like the state of charge. One possibility of classification of these physics-based models is their level of geometric resolution, including three-dimensionally resolved models and geometrically homogenized models, known as Doyle-Fuller-Newman or pseudo two-dimensional models. Within this study, the advantages and drawbacks of these two types of models are identified within a wide range of the design parameter values. Therefore, the sensitivity of an output quantity of the models on one or a combination of parameters is compared. In particular, the global sensitivity, i.e., the sensitivity in a wide range of parameter values, is computed by using the Sobol indices as a measure. Furthermore, the local sensitivity of the difference in the output quantities of both models is evaluated to identify regions of parameter values in which they contain significant deviations. Finally, remarks on the potential interplay between both models to obtain fast and reliable results are given.

The reliable computation of microstructure metrics such as specific surface area and tortuosity factors is key to bridge the gap between the battery microscale and fast, homogenized cell models. In this work, we present an approach to compute the surface area of phases based on pixelated image data which is both easy-to-implement and computationally efficient. The concept is inspired from the diffuse surface representation in phase-field methods. Subsequently, the approach is validated and compared with common python libraries on two benchmark cases and actual battery microstructure data. The results underline the reliability and fast computational performance of the approach. Furthermore, the concept of through-feature connectivity in pixelated image data is introduced and explored to quantify the reliability of tortuosity factor computations. Overall, this work enhances the computational tools to bridge the scale from battery microstructures to cell models and gives an overview of state-of-the-art methodology. The developed code is published to further accelerate the scientific progress in this field.

The effects of polysulfide shuttle and volume expansion in lithium sulfur batteries limit their practical applications. In this work, a two-dimensional fabric with graphene cage interweaving was designed by the chemical vapor deposition method to resolve these issues. It has a large number of micropores, mesopores, and macropores. Sulfur was deposited in these pores by melting method to form sulfur/graphene complex. Polysulfides were confined within these pores, making them less likely to diffuse and shuttle. Graphene walls have strong flexibility and can alleviate the volume expansion effect during charge and discharge process. Sulfur/graphene complex as active materials were directly coated on aluminum foil by graphene oxide to build lithium-sulfur battery, where graphene oxide served not only as an adhesive but also as a conductive agent to improve the electrochemical performances of batteries. The lithium-sulfur battery had an initial capacity of 1400 mAh g-1 and high capacity retention (500 mAh g-1 after 200 cycles at 0.2 C rate). These results suggest that the reasonable design of material morphology for sulfur loading will effectively improve the performance of lithium sulfur batteries.

Understanding Li nucleation and growth mechanism during charging in solid electrolytes (SEs) is essential in development of all-solid-state batteries with metallic Li, because the Li dendrite could cause internal short-circuit by penetration of SE. However, it is still under debate how the factors including degradation of SE layer, the stacking pressure, and the microstructure affect the Li nucleation and growth in SE. In this study, the coupled current-deposition-stress models using the two-dimensional artificial SE structures have been developed by combination of finite element method and Monte Carlo simulations. The model assumed that Li flux on the SE grain induces an eigen strain in the deposited Li region, and Li grows into the SE layer by breaking grain boundary (GB). Degradation of SE was modelled as the decrease of fracture strength of GB using a coefficient. The effects of these microstructure and operation factors on GB fracture and Li deposition have been evaluated and discussed.

Understanding the electrochemical behavior of hydrogen adsorption at Pt-group metal surfaces, particularly in the context of non-well-defined nanoparticle surfaces, is crucial for advancing electrocatalytic applications such as the hydrogen evolution reaction (HER). This study investigates the non-Nernstian pH shifts observed for underpotential deposited Hupd-like cyclic voltammetry peaks on Pt, Ir, Pd, and Rh nanoparticles. Utilizing density functional theory calculations, we explore the potential-dependent stability of H and OH adsorbates at undercoordinated surface sites, emphasizing the role of non-ideal electrosorption valencies in these shifts. Our results support that the peaks arise predominantly from a direct H-OH replacement process and suggest the primary influence of partial charge transfer. The theoretical predictions show good agreement with experimental observations across various Pt-group metals, even on non-well-defined surfaces, and provide insights into cation-specific effects at Pt across the entire pH scale. This work not only clarifies the origin of the Hupd-like peak within the water stability region but also offers a foundation for understanding cation effects in HER kinetics, paving the way for more detailed analyses of cation type, concentration, and interfacial solvent structure.

Lithium-sulfur (Li-S) batteries are attracting significant attention because of their high capacity and high energy density. For Li-S batteries using highly concentrated sulfolane-based electrolytes (i.e., sparingly solvating electrolytes for Li2Sx) and S8 active materials, we developed a method of lifetime testing to evaluate the dynamic and static degradation behavior. Short- to medium-term discharge/charge tests and long-term storage tests were conducted. The capacity degradation after cycling in the medium term was attributed to changes in the utilization of long- and short-chain Li2Sx due to the incomplete recovery to S8. Storage tests were conducted under different temperature and state-of-charge (SOC) conditions. The discharge capacity at SOC70% decreased significantly more than that at SOC100%, demonstrating the difference in degradation behavior compared to that of typical lithium-ion batteries. The capacity retention rate decreased linearly with storage time up to approximately 9 months, revealing that degradation was accelerated by 2 times at SOC100% compared with that at SOC0%, from a simple liner analysis. The capacity also decreased with increasing storage temperature, exhibiting ∼2.4 times more degradation at 333.1 K than at 303.2 K. This may be due to the enhanced dissolution of the Li2Sx reaction intermediates in the electrolyte and the redox-shuttle effect.

The study demonstrates an in-house developed eco-friendly vibration-assisted electrochemical polishing (ECP) process, where the electrolyte flushing with the squeezing action of the vibrating tool eliminates the electrolytic by-products in the inter-electrode gap (IEG). A two-dimensional numerical model is developed to study the squeezing effect on changing bubble faction, anodic dissolution, and current density distribution. The effect of process parameters such as current density, electrolyte flow velocity, IEG, vibration amplitude of the tool, and vibration speed is analysed based on the experimental design matrix of response surface methodology (RSM) for minimising average surface roughness (Ra) of SS 304 component fabricated by electrical discharge machining. The numerical results indicated an increased flow velocity at IEG due to the vibration, resulting in an effective flushing of generated gasses. Current, IEG, vibration speed of the tool, vibration amplitude, and interaction between current-IEG, current-vibration speed, and IEG-vibration speed are identified as the most influential parameters by implementing the analysis of variance. The parameters are optimised using RSM, leading to a 96.71% reduction in Ra value and a 62.54% lower Ra value than the ECP without vibration, indicating the effectiveness of vibration-assisted ECP to achieve a high surface finish using eco-friendly electrolytes.

The chemical dissolution of anodic alumina film was investigated using the re-anodization technique. The formation of thick oxide films in an alkaline electrolyte is thought to be difficult to achieve due to the high pH value and high solubility of anodic alumina. The dissolution rate of anodic film was found to be strongly affected by the pH of the solution used for chemical dissolution; the film dissolved significantly faster in a sodium hydroxide solution having a high pH of 13.11 than in acidic solutions commonly used for anodization, such as sulfuric acid (pH 0.98) and phosphoric acid (pH 1.54). Nevertheless, the addition of glycerol to the sodium hydroxide solution effectively suppressed the chemical dissolution of the anodic film. The change in solubility of the anodic alumina film in solution was greatly affected by the change in the dissociation of the solute in solution. The results demonstrated that oxide films more than 10 μm thick were produced in an alkaline electrolyte by adding glycerol to the solution. The suppression of the chemical dissolution of alumina by the addition of alcohol has thus been shown to occur not only in acid solutions but also in alkaline solutions.

Solid polymer electrolytes are promising alternatives to traditional liquid electrolytes for use in lithium batteries. Poly(ethylene glycol) diacrylate (PEGDA) is a versatile cross-linkable monomer that promotes easy incorporation of a variety of filler materials for solid electrolyte synthesis without the use of solvents. This study examines the effects that varying concentrations of SiO2, CeZrO4, V2O5, and succinonitrile have on the electrochemical performance of UV-cured PEGDA electrolytes. A composite polymer electrolyte containing 8% V2O5 and 30% succinonitrile in PEGDA was synthesized and exhibited a room-temperature ionic conductivity of 1.43x10-4 S/cm. The improvement in ionic conductivity of this electrolyte may be attributed to the synergistic effect of the two incorporated fillers resulting in decreased crystallinity of the polymer matrix. This study demonstrates that polymer electrolyte characteristics can be optimized by combining the benefits of multiple fillers.

We investigated the fabrication of graphite/PVdF anodes using electrostatic dry spray-coating, employing two different PVdF binders with different physicochemical properties such as primary particle size, crystallinity, melting temperature, and viscosity. We examine and compare the morphological, mechanical, electrical, and electrochemical properties of the dry-sprayed electrodes (DSEs). Significant differences were observed, particularly in terms of adhesion/cohesion, electrical resistivity, tortuosity, and electrochemical performance, with the PVdF binder characterized by a smaller particle size (178 nm) and a slightly higher melting temperature range (165–172°C), demonstrating superior long-term cycling stability. Specifically, the best electrode made with this binder achieved 188.3 mAh g-1 with over 94.9% capacity retention after 200 cycles. In contrast, the best electrode made with the PVdF binder with a larger particle size (270 nm) and a lower melting temperature range (155–172°C), showed a performance of 173.9 mAh g-1 with 88.3% capacity retention under the same conditions. Our findings highlight the necessity of adjusting fabrication conditions according to the specific characteristics of each PVdF binder to optimize the overall performance of the DSEs.