Ionic Transference Number Research Articles

Emerging trends and prospects in aqueous electrolyte design: Elevating energy density and power density of multivalent metal-ion batteries

Aqueous batteries, using multivalent metallic charge carriers (Zn2+, Mg2+, Ca2+, Al3+), show promise as next-generation electrochemical energy storage due to their adequate energy density, high power density, and cost-effectiveness. The electrolyte, serving as a bridge between the cathode and anode, plays a crucial role in functionality. However, the use of aqueous electrolytes introduces issues such as limited voltage range, slow kinetics of multivalent cations, and side reactions on metal surfaces. Electrolyte engineering has emerged as a key solution to overcome major challenges in multivalent metal-ion batteries. This innovative approach involves optimizing factors such as electrolyte concentration, specific additives, pH management, and manipulating the ligand effect of cation salts. Additionally, incorporating anti-freezing agents is crucial. A systematic review of this domain is crucial for further development and refinement of electrolyte engineering strategies. This review should primarily focus on assessing how these modifications can enhance energy and power densities, broaden the operational range of the batteries (by adjusting water activity and LUMO/HOMO energy levels), improve cation transport (via enhanced ion conductivity, dielectric constant, transference number, and solvation structure), and effectively mitigate detrimental side reactions, such as metal deposition, interphase formation, and hydrogen bonding regulation. The electrolyte design strategies in multivalent metal-ion systems are outlined in terms of their effectiveness in smoothing metal dendrites, managing solvation shells and free water molecules, and minimizing side reactions between the metal surface and electrolyte. The article proposes future innovation directions and development prospects for enhancing electrolyte design engineering in these systems.

Non‐Resonant Structure Induces N‐Rich Solid Electrolyte Interface toward Ultra‐Stable Solid‐State Lithium‐Metal Batteries

AbstractThe practical application of all‐solid‐state lithium metal batteries (ASSLMBs) is limited by lithium (Li) anode instability including Li dendrite formation and deteriorating interface with electrolytes. Here, a functional additive, isosorbide mononitrate (ISMN) with a non‐resonant structure (O2−N−O−) is reported, which improves its reactivity and is utilized to build a stable N‐rich solid electrolyte interface, effectively alleviating Li dendrite and side reactions for poly(vinylidene fluoride) (PVDF)‐lithium bis(trifluoromethane sulfonyl) imide (LiTFSI)‐based electrolyte (PLE‐ISMN). In addition, the ion‐dipole interaction between ISMN and Li ions facilitates the dissociation of LiTFSI to form carrier ions, improving the ionic conductivity (4.4 × 10−4 S cm−1) and transference number (0.50) of PLE‐ISMN. Consequently, the Li/Li symmetric cell delivers a high critical current density of 2.0 mA cm−2 and stable Li stripping/plating cycling over 5000 h with a capacity of 1.0 mAh cm−2. Moreover, the Li|LiFePO4 cell delivers an excellent initial discharge capacity of 154.0 mAh g−1 with an outstanding capacity retention of 88.9% after 500 cycles at 0.5 C. The Li|LiNi0.8Co0.1Mn0.1O2 cell also exhibits a good cycling performance at 4.4 V at 1 C.

Synthesis and Properties of Polyvinylidene Fluoride-Hexafluoropropylene Copolymer/Li6PS5Cl Gel Composite Electrolyte for Lithium Solid-State Batteries.

Gel electrolytes for lithium-ion batteries continue to replace the organic liquid electrolytes in conventional batteries due to their advantages of being less prone to leakage and non-explosive and possessing a high modulus of elasticity. However, the development of gel electrolytes has been hindered by their generally low ionic conductivity at room temperature and high interfacial impedance with electrodes. In this paper, a poly (vinylidene fluoride)-hexafluoropropylene copolymer (PVdF-HFP) with a flexible structure, Li6PS5Cl (LPSCl) powder of the sulfur-silver-germanium ore type, and lithium perchlorate salt (LiClO4) were prepared into sulfide gel composite electrolyte films (GCEs) via a thermosetting process. The experimental results showed that the gel composite electrolyte with 1% LPSCl in the PVdF-HFP matrix exhibited an ionic conductivity as high as 1.27 × 10-3 S·cm-1 at 25 °C and a lithium ion transference number of 0.63. The assembled LiFePO4||GCEs||Li batteries have excellent rate (130 mAh·g-1 at 1 C and 54 mAh·g-1 at 5 C) and cycling (capacity retention was 93% after 100 cycles at 0.1 C and 80% after 150 cycles at 0.2 C) performance. This work provides new methods and strategies for the design and fabrication of solid-state batteries with high ionic conductivity and high specific energy.

Characterization of methylcellulose based composite polymer electrolytes reinforced with Reduced-Graphene oxide

This work reports the effect of reduced-graphene oxide (ReGO) on the conductivity and other properties of ammonium bromide (NH4Br) doped methylcellulose-based electrolytes. Hydrazine monohydrate, N2H2·H2O is used as the reducing agent in synthesising ReGO from graphene oxide (GO). Methylcellulose-NH4Br-ReGO based electrolytes are prepared using solution cast method. Fourier transform infrared (FTIR) analysis provides the evidence of interaction between the materials. Introduction of 0.3 wt% ReGO has maximized the conductivity of electrolyte up to (9.00 ± 0.38) × 10−4 S cm−1. From transport analysis, the conductivity is found to be influenced by the number density (n) and mobility (μ) of ion. Conductivity result is supported by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) analysis. Ionic transference number (tion) of the highest conducting electrolyte is found to be 0.94, thus confirming ions as the dominant charge carriers. The highest conducting electrolyte shows a potential stability up to 1.7 V.

Weak Electrostatic Force on K+ in Gel Polymer Electrolyte Realizes High Ion Transference Number for Quasi Solid-State Potassium Ion Batteries.

Quasi-solid-state potassium-ion batteries (SSPIBs) are of great potential for commercial use due to the abundant reserves and cost-effectiveness of resources, as well as high safety. Gel polymer electrolytes (GPEs) with high ionic conductivity and fast interfacial charge transport are necessary for SSPIBs. Here, the weak electrostatic force between K+ and electronegative functional groups in the ethoxylated trimethylolpropane triacrylate (ETPTA) polymer chains, which can promote fast migration of free K+, is revealed. To further enhance the interfacial reaction kinetics, a multilayered GPE by in situ growth of poly(vinylidenefluoride-co-hexafluoropropylene) (PVDF-HFP) on ETPTA (PVDF-HFP|ETPTA|PVDF-HFP) is constructed to improve the interface contact and provide sufficient K+ concentration in PVDF-HFP. A high ion transference number (0.92) and a superior ionic conductivity (5.15 × 10-3 S cm-1) are achieved. Consequently, the SSPIBs with both intercalation-type (PB) and conversion-type (PTCDA) cathodes show the best battery performance among all reported SSPIBs of the same cathode. These findings demonstrate that potassium-ion batteries have the potential to surpass Li/Na ion batteries in solid-state systems.

Confining Polymer Electrolyte in MOF for Safe and High-Performance All-Solid-State Sodium Metal Batteries.

Nanoconfined polymer molecules exhibit profound transformations in their properties and behaviors. Here, we present the synthesis of a polymer-in-MOF single ion conducting solid polymer electrolyte, where polymer segments are partially confined within nanopores ZIF-8 particles through Lewis acid-base interactions for solid-state sodium-metal batteries (SSMBs). The unique nanoconfinement effectively weakens Na ion coordination with the anions, facilitating the Na ion dissociation from salt. Simultaneously, the well-defined nanopores within ZIF-8 particles provide oriented and ordered migration channels for Na migration. As a result, this pioneering design allows the solid polymer electrolyte to achieve a Na ion transference number of 0.87, Na ion conductivity of 4.01×10-4 S cm-1, and an extended electrochemical voltage window up to 4.89 V vs. Na/Na+. The assembled SSMBs (with Na3V2(PO4)3 as the cathode) exhibit dendrite-free Na-metal deposition, promising rate capability, and stable cycling performance with 96 % capacity retention over 300 cycles. This innovative polymer-in-MOF design offers a compelling strategy for advancing high-performance and safe solid-state metal battery technologies.

Chitosan as a suitable host for sustainable plasticized nanocomposite sodium ion conducting polymer electrolyte in EDLC applications: Structural, ion transport and electrochemical studies

The challenge in front of EDLC device is their low energy density compared to their battery counter parts. In the current study, a green plasticized nanocomposite sodium ion conducting polymer blend electrolytes (PNSPBE) was developed by incorporating plasticized Chitosan (CS) blended with polyvinyl alcohol (PVA), doped with NaBr salt with various concentration of CaTiO3 nanoparticles. The most optimized PNSPBE film was subsequently utilized in an EDLC device to evaluate its effectiveness both as an electrolyte and a separator. Structural and morphological changes were assessed using XRD and SEM techniques. The PNSPBE film demonstrated a peak ionic conductivity of 9.76×10−5 S/cm, as determined through EIS analysis. The dielectric and AC studies provided further confirmation of structural modifications within the sample. Both TNM and LSV analyses affirmed the suitability of the prepared electrolyte for energy device applications, evidenced by its adequate ion transference number and an electrochemical potential window of 2.86 V. Electrochemical properties were assessed via CV and GCD techniques, confirming non-Faradaic ion storage, indicated by the rectangular CV pattern at low scan rates. The parameters associated with the designed EDLC device including specific capacitance, ESR, power density (1950 W/kg) and energy density (12.3 Wh/kg) were determined over 1000 cycles.

Poly (Vinylidene Fluoride-Hexafluoropropylene)-Lithium Titanium Aluminum Phosphate-Based Gel Polymer Electrolytes Synthesized by Immersion Precipitation for High-Performance Lithium Metal Batteries.

Gel polymer electrolytes (GPEs) have high safety and excellent electrochemical performance, so applying GPEs in lithium batteries has received much attention. However, their poor lithium ion transfer number, cycling stability, and low room temperature ionic conductivity seriously affect the utilization of gel polymer electrolytes. This paper successfully synthesized flexible poly (vinylidene fluoride-hexafluoropropylene)-lithium titanium aluminum phosphate (PVDF-HFP-LATP) gel polymer electrolytes using the immersion precipitation method. The resulting GPE has a porous honeycomb structure, which ensures that the GPE has sufficient space to store the liquid electrolyte. The GPE has a high ionic conductivity of 1.03 ×10-3 S cm-1 at room temperature (25 °C). The GPE was applied to LiFePO4/GPE/Li batteries with good rate performance at room temperature. The discharge specific capacity of 1C was as high as 121.5 mAh/g, and the capacity retention rate was 94.0% after 300 cycles. These results indicate that PVDF-HFP-LATP-based GPEs have the advantage of simplifying the production process and can improve the utility of gel polymer lithium metal batteries.

Robust Solid-State Na-CO2 Battery with Na2.7Zr2Si2PO11.7F0.3-PVDF-HFP Composite Solid Electrolyte and Na15Sn4/Na Anode.

Solid-state Na-CO2 batteries are a kind of energy storage devices that can immobilize and convert CO2. They have the advantages of both solid-state batteries and metal-air batteries. High-performance solid electrolyte and electrode materials are important for improving the performance of solid-state Na-CO2 batteries. In this work, we investigate the influence of fluorine doping on the structure and ionic conductivity of Na3Zr2Si2PO12 (NZSP). An ionic conductive solid electrolyte membrane was prepared by compositing the inorganic solid electrolyte Na2.7Zr2Si2PO11.7F0.3 (NZSPF3) with poly(vinylidene fluoride)-co-hexafluoropropylene (PVDF-HFP). It shows an ionic conductivity of up to 2.17 × 10-4 S cm-1 at room temperature, a high sodium ionic transfer number of ∼0.70, a broad electrochemical window of ∼5.18 V, and better mechanical strength. Furthermore, we studied the Na15Sn4/Na composite foil with the ability to inhibit dendrite as the anode for solid-state Na-CO2 batteries. Through density functional theory (DFT) calculations, the Na15Sn4 particle has been verified with a strong sodiophilic property, which reduces the nucleation barrier during the deposition process, leading to a lower overpotential. The symmetric cell assembled with the composite solid-state electrolyte NZSPF3-PVDF-HFP and Na15Sn4/Na composite anode can inhibit the growth of Na dendrites effectively and maintain the stability of the whole cell structure. Solid-state Na-CO2 batteries assembled with Ru-carbon nanotube (Ru-CNTs) as cathode catalysts exhibit a high discharge capacity of 6371.8 mAh g-1 at 200 mA g-1, excellent cycling stability for 1100 h, and good rate performance. This work provides a promising strategy for designing high-performance solid-state Na-CO2 batteries.

Reversible characterization of power generation and steam electrolysis for protonic ceramic cells with bi-layer electrolyte of BaZr0.8Yb0.2O3-δ and BaZr0.1Ce0.7Y0.1Yb0.1O3-δ

This work presents the reversible operation between fuel cell and steam electrolysis modes in a protonic ceramic cell (PCC) with a bi-layer electrolyte structure composed of BaZr0.8Yb0.2O3-δ and BaZr0.1Ce0.7Y0.1Yb0.1O3-δ. PCC using the bi-layer electrolyte demonstrated a slightly less leakage current and an improved performance than other samples using only BaZr0.8Yb0.2O3-δ electrolyte. In the fuel cell mode, the cell exhibited the maximum power density of 0.61 W cm−2 at 600 °C. Meanwhile, in steam electrolysis mode at 600 °C, the cell showed a current density of 0.94 A cm−2 and a Faraday efficiency 46% when operating in thermoneutral voltage. However, when evaluated in steam electrolysis mode at 600 °C with a current density of 0.6 A cm−2 for 250 h, it was confirmed that the air electrode had deteriorated, causing a decrease in Faraday efficiency from 46% to 25% after 250 h of operation, indicating a degradation in the efficacy of leak current mitigation during extended operating conditions. After 250 h operating a distribution of relaxation times analysis revealed a characteristic peak at low frequencies that could be associated with variation in the ionic transference number of the electrolyte after long-term operation.

Tunneling Interpenetrative Lithium Ion Conduction Channels in Polymer-in-Ceramic Composite Solid Electrolytes.

Polymer-in-ceramic composite solid electrolytes (PIC-CSEs) provide important advantages over individual organic or inorganic solid electrolytes. In conventional PIC-CSEs, the ion conduction pathway is primarily confined to the ceramics, while the faster routes associated with the ceramic-polymer interface remain blocked. This challenge is associated with two key factors: (i) the difficulty in establishing extensive and uninterrupted ceramic-polymer interfaces due to ceramic aggregation; (ii) the ceramic-polymer interfaces are unresponsive to conducting ions because of their inherent incompatibility. Here, we propose a strategy by introducing polymer-compatible ionic liquids (PCILs) to mediate between ceramics and the polymer matrix. This mediation involves the polar groups of PCILs interacting with Li+ ions on the ceramic surfaces as well as the interactions between the polar components of PCILs and the polymer chains. This strategy addresses the ceramic aggregation issue, resulting in uniform PIC-CSEs. Simultaneously, it activates the ceramic-polymer interfaces by establishing interpenetrating channels that promote the efficient transport of Li+ ions across the ceramic phase, the ceramic-polymer interfaces, and the intervening pathways. Consequently, the obtained PIC-CSEs exhibit high ionic conductivity, exceptional flexibility, and robust mechanical strength. A PIC-CSE comprising poly(vinylidene fluoride) (PVDF) and 60 wt % PCIL-coated Li3Zr2Si2PO12 (LZSP) fillers showcasing an ionic conductivity of 0.83 mS cm-1, a superior Li+ ion transference number of 0.81, and an elongation of ∼300% at 25 °C could be produced on meter-scale. Its lithium metal pouch cells show high energy densities of 424.9 Wh kg-1 (excluding packing films) and puncture safety. This work paves the way for designing PIC-CSEs with commercial viability.

Ion correlations in quaternary ionic liquids electrolytes

Lithium-ion batteries are currently the most popular and widely used energy storage devices, almost omnipresent within modern society in portable devices, electrical vehicles, energy storage stations, and so on. The demand for more efficient, more durable, and more sustainable batteries is rapidly growing. The electrolyte is a key element to improve the performance of lithium-ion batteries. In this work, we focus on quaternary ionic liquid electrolyte (ILE), which uses a four-component ionic liquid as the solvent. Quaternary ILE has found wide applications in energy storage systems, but the ion transport in the electrolyte has not been fully characterized to provide the best strategy for performance optimisation. In this work, we systematically analyse the ion transport in the quaternary ILE and uncover how the correlations between various ions affect the conductivity of the electrolyte. We have found that lithium ions are transported in charge clusters, leading to a negative effective transference number of lithium ions. Furthermore, we identify the stable cluster conformations in ILE by cluster analysis and quantum chemical computing. This work highlights the necessity of considering ion correlations in multi-component electrolyte systems.

Cation-Conduction Dominated Hydrogels for Durable Zinc-Iodine Batteries.

Zinc-iodine batteries have the potential to offer high energy-density aqueous energy storage, but their lifetime is limited by the rampant dendrite growth and the concurrent parasite side reactions on the Zn anode, as well as the shuttling of polyiodides. Herein, a cation-conduction dominated hydrogel electrolyte is designed to holistically enhance the stability of both zinc anode and iodine cathode. In this hydrogel electrolyte, anions are covalently anchored on hydrogel chains, and the major mobile ions in the electrolyte are restricted to be Zn2+. Specifically, such a cation-conductive electrolyte results in a high zinc ion transference number (0.81) within the hydrogel and guides epitaxial Zn nucleation. Furthermore, the optimized Zn2+ solvation structure and the reconstructed hydrogen bond networks on hydrogel chains contribute to the reduced desolvation barrier and suppressed corrosion side reactions. On the iodine cathode side, the electrostatic repulsion between negative sulfonate groups and polyiodides hinders the loss of the iodine active material. This all-round electrolyte design renders zinc-iodine batteries with high reversibility, low self-discharge, and long lifespan.

Nanoengineered Functional Cellulose Ionic Conductor Toward High‐ Performance All‐Solid‐State Zinc‐Ion Battery

AbstractThe rechargeable zinc‐ion battery is regarded as a promising candidate for the next‐generation energy storage system, however, zinc dendrite growth and hydrogen evolution reaction (HER) have greatly hindered the practical application of the battery. Herein, a functionalized, nano‐engineering Zn2+ coordinated carboxylate cellulose solid‐state electrolyte (denoted as Zn‐CCNF@XG) for zinc‐ion battery is constructed through a straightforward approach. According to the experimental and density functional theory (DFT) results of dissociation energy, the notably decreased dissociation energy by −COOH is favorable to Zn2+ de‐coordinating and rapid ion‐hopping in Zn‐CCNF@XG to achieve high ionic conductivity and transference number. More importantly, the engineered molecular channels are beneficial to enlarging the distance between the nanofibril chains, providing a larger space for the movement of Zn2+. Benefiting from the coordination of Zn2+ with −OH in carboxylate cellulose nanofibrils, Zn‐CCNF@XG as a good ionic conductor displays a high ionic conductivity of 1.17 × 10−4 S cm−1 and transference number of 0.78. The Zn||NaV3O8·1.5H2O full cell with Zn‐CCNF@XG maintains a capacity retention of 83.46% with a coulombic efficiency of 99.99% after 3000 cycles (1 A g−1). The proposed strategy by introducing a functional group to cellulose nanofibrils effectively avoids the dendrite and HER, providing valuable guidelines for the practical application of zinc‐ion batteries.

Ion-dipole interactions assist small molecular additives to regulate Li+ coordination of poly(ethylene) oxide-based polymer electrolyte

Polymer electrolyte is an attractive material for constructing high-performance solid-state batteries. However, the overall low room-temperature ionic conductivity and low transference number impede the practical application of polymer electrolyte. Ion-dipole interaction, as non-covalent interactions, has the potential to regulate Li+ coordination. It will contribute to the selectivity filter of ion conduction and improve overall ion conduction performance. Herein, we introduced benzene sulfonamide (BS) and N-methylbenzenesulfonamide (NBS) into PEO-LiTFSI complexes, respectively. The ion-dipole interactions of Li···-N-H might be provided by the organic molecules. Due to the difference in the molecular structure between BS and NBS, the stronger ion-dipole interactions between NBS and Li+ could significantly improve the coordination of Li+. As a result, PEO-LiTFSI-NBS delivers an extraordinary ionic conductivity of 1.08 × 10−4 S cm−1 at 30 °Ϲ and a high lithium ion transference number of 0.77. When employed in assembling LiFePO4|Li solid-state battery, the specific discharge capacity could reach 151.90 mAh g−1 with a high coulombic efficiency of around 99.92 % at 50 μA cm−2 (35 °Ϲ).

Ion Conducting Polyethylene Oxide‐Based Polymer Electrolyte Dopped with Ionic Liquid‐Trifluoromethanesulfonic Chloride

AbstractIn last few decades, polymer electrolyte is the most promising candidate for the fabrication of electrochemical devices. In current work, the influence of adding the room‐temperature ionic liquid (trifluoromethanesulfonic chloride – CClF3O2S) in polyethylene oxide (PEO): ammonium iodide (NH4I) polymer electrolyte has been studied. The IL‐doped polymer electrolyte films are synthesized by solution casting method with varying stoichiometric ratios. Several experimental techniques including optical polarizing microscope, impedance spectroscopy, X‐ray diffraction, Linear sweep voltammetry, Ionic transference number thermal analysis, and electrical conductivity measurements at room temperature have been studied in detail. The complex material's maximum conductivity has been determined to be 3.3 × 10−5 S cm−1 at room temperature. The POM images show the increase in amorphous region which further confirm the improvement in ionic conductivity. Ionic transference number 0.96 shows the system is purely ionic in nature. The ESW of the IL doped polymer electrolyte is also sawed to be 3.32 V which is suitable for the fabrication of electrochemical devices.

Influence of Carbon Black on Conductivity and Structure of Polyethylene Oxide Based Polymer Electrolyte Film

AbstractThe potential applications of carbon black are expected to grow as science and technology improve offering up new possibilities for innovation throughout disciplines included in the field of energy storage. The present work shows the influence of carbon black to improve the ionic conductivity of the polymer electrolyte. The synthesis of polyethylene oxide: ammonium iodide based polymer electrolyte incorporated with carbon black varying from 0.01 to 0.06 wt% with respect to PEO: NH4I system by solution casting method. Different characterizations like polarized optical microscopy (POM), impedance spectroscopy, and ionic transference number (tion) are studied in detail. The maximum ionic conductivity is achieved at 0.05 wt% carbon black shows 1.20 × 10−5 S cm−1 at ambient temperature. In accordance with POM data, the amorphous region has increased whereas the crystalline region has shrunk which further indicated the increase in ionic conductivity. The value of (tion) is calculated to be 0.97 which shows the system is ionic in nature. PEO based polymer electrolyte doped carbon black can be used for the fabrication of energy storage devices.

Electrical and Structural Properties of Poly (Methyl Methacrylate) Doped Potassium Iodide (KI) Solid Polymer Electrolyte

AbstractA high‐conducting salt‐doped polymer electrolyte layer has been created here for use in photocell technologies. The solution casting method is used to produce ion conducting film where poly (methyl methacrylate) (PMMA) is used as the host polymer and potassium iodide (KI) as the dopant. The conductivity and amorphic increases of the polymer electrolytes with the addition of salt concentrations helps in the enhancement of the charge transfer properties. Using electrochemical impedance spectroscopy (EIS), ionic conductivity is evaluated where maximum conductivity is 3.99 × 10−6 S cm‐1 at 20 wt% KI concentration. Polarized optical microscopy (POM) shows the reduction in crystallinity by salt doping, while Fourier transforms infrared spectroscopy (FTIR) shows the complexation as well as composite nature of the film. Ionic transference number (tion) measurement shows the predominantly ionic nature of this polymer electrolyte.

Coaxially MXene-confined solid-state electrolyte for flexible high-rate lithium metal battery

Solid-state polymer electrolytes (SPEs) possess conspicuous merits of facile manufacturing, superior mechanical toughness, and favorable chemical stability with Li anodes, but the intrinsically low room temperature ionic conductivity (∼10−8 −10−6 S cm−1) and negligible Lithium-ion transfer number (0.1–0.2) badly inhibited its commercial application in lithium metal batteries (LMBs). Herein, we design the three-dimensionally and coaxially MXene-confined solid-state polymer electrolyte (C-MX SPE) for the directional acceleration movement of Li+ ion by introducing MXene nanosheets into the polyacrylonitrile (PAN) fiber. Benefiting from the confinement effect, the homogeneously and coaxially MXene-confined SPE possess an impressive Li+ ion transference number of 0.72 and ionic conductivity of 3.07 × 10−3 S cm−1 at room temperature, which are 3 and 20 times of magnitude higher than the randomly MXene-dispersed (R-MX) SPE (0.22 and 1.61 ×10−4 S cm−1), respectively. Also, the Lithium/SPE/Lithium symmetric cell exhibits a flat galvanostatic charge/discharge under 1 mA cm−2 for 2000 h without dendrites, revealing its 3D skeleton structure could mechanically suppress Li dendrite growth. Based on it, the assembled flexible solid-state lithium metal batteries (SSLMBs) possess a rate-capability of 101 mAh g−1 @ 10 C, a capacity retention of 85.18% after 500 cycles @ 1 C at room temperature and a stability of bending-needling-cutting performance. Evidently, this three-dimensionally and coaxially MXene-confined SPE may represent a promising strategy to address the random distribution and agglomeration of inorganic fillers in SPE and guide a direction for the development of high-performance, secure, and flexible SSLMBs.

PEMBANGUNAN PENYIMPANAN TENAGA HIJAU DARIPADA SELULOSA BAKTERIA, SELULOSA METIL DAN KANJI KENTANG

A natural polymer known as bacterial cellulose (BC), derived from a symbiotic culture of bacteria and yeast (SCOBY), is utilized as the electrodes for the electrochemical double-layer capacitors (EDLC). Bacterial cellulose which can be easily obtained from the local market, possesses an exceptional structure that allows for the elimination of non-biodegradable binders and the use of current collectors in the EDLC electrodes. A green polymer electrolyte system consisting of methylcellulose, potato starch and lithium bromide. This electrolyte demonstrates a conductivity of (1.38 ± 0.54) × 10-4 S/cm, electrochemical stability of 1.3 V, and an ionic transference number of 0.98. The optimized electrolyte is used in the EDLC. Cyclic voltammetry analysis reveals that he fabricated EDLC has a capacitive behavior without any peaks indicating redox reactions. The EDLC undergo charging and discharging for up to 5000 cycles, with specific capacitances of 26 F/g. The EDLC shows a maximum power density of 1730 W/kg, with energy density of 3.6 Wh/kg.