Stable Electrolyte Research Articles

Starfish-Inspired Solid-State Li-ion Conductive Membrane with Balanced Rigidity and Flexibility for Ultrastable Lithium Metal Batteries.

The performance of solid-state lithium-metal batteries (SSLMB) is often constrained by the low ionic conductivity, narrow electrochemical window, and insufficient mechanical strength of polyethylene oxide (PEO)-based electrolytes. Inspired by the soft-outside, rigid-inside structure of starfish, we designed multifunctional "starfish-type" composite polymer electrolytes (CPEs) using electrospinning technology. These CPEs feature a three-dimensional rigid skeleton network composed of polyacrylonitrile/metal-organic frameworks/ionic liquids (PAN/MOFs/ILs), creating continuous and efficient Li+ transport channels: MOFs impart rigidity, PEO acts as a cushioning outer layer to enhance interfacial compatibility, and ILs reduce interfacial resistance. The resulting CPEs exhibited excellent ionic conductivity (4.37×10-4 S cm-1), a wide electrochemical window (5.34 V), uniform lithium-ion flux, and a high transference number (0.69). Leveraging these synergistic advantages, the Li/CPEs/Li symmetric cell demonstrated outstanding dendrite suppression for over 1300 hours, and the LiFePO4/CPEs/Li cell retained 90.1 % capacity after 2100 cycles at 1.0 C, which is the best performance reported for SSLMB with MOF/PEO. The formation of multi-component solid-electrolyte interphase and its role in stabilizing lithium metal cycling were systematically elucidated through theoretical simulations and spectroscopic analysis. This nature-inspired design provides a promising strategy for the development of stable solid-state electrolytes with extended lifespans.

Antiplasmodial Potentials, Phytocompounds and the Possible Toxic Effects of Administration of Ethylacetate Extract of Spondias mombin Linn.

Malaria, caused by Plasmodium parasites, is a global health concern. Natural products, such as plant extracts, are investigated for new antimalarial agents. Spondias mombin, traditionally used for medicinal purposes, was examined for its effects on parasitemia, haematological parameters, antioxidant activities, liver function biomarkers, and serum electrolytes in Plasmodium berghei-infected mice. Mice received varying doses of the ethylacetate extract. Various dosages of the extract and the prescribed medication dramatically slowed the parasite's growth. The extract significantly improved red blood cell (RBC) and platelet counts, particularly at higher doses. Hemoglobin levels were decreased dose-dependently. Antioxidant analysis showed increased superoxide dismutase (SOD), glutathione peroxidase (GPx), and reduced catalase (CAT) activities and malondialdehyde (MDA) levels, indicating robust antioxidant properties. Liver function tests showed mixed effects, with elevated AST, ALP, and TB levels at some doses, yet decreased ALT at the highest dose, suggesting possible hepatoprotective effects. Serum electrolyte levels remained stable. Seventy-eight (78) bioactive components were identified in the extract by GC-MS analysis. The extract demonstrated substantial antimalarial and antioxidant capacities, with minimal liver stress and stable electrolyte levels, suggesting safety as an adjunct therapy for malaria. Further research is needed to ascertain the specific antimalarial bioactive constituents and their mechanisms of action.

Shielding Fluoride Ion Basicity through Diurea Coordination for Nonaqueous Fluoride Shuttle Batteries

AbstractThe strong basicity of fluoride ions leads to detrimental nucleophilic attack on organic components in the electrolytes, such as β‐hydrogen elimination reactions with organic cations and solvents, converting “naked” F− into corrosive and unstable bifluoride (HF2−) ions. These reactions significantly constrain the choice of suitable solvents and salts to develop electro(chemical) stable fluoride ion electrolytes. In this work, we replaced the triple water ligands typically present in industrial organic fluoride salts with dual 1,3‐diphenylurea (DPU) coordination via hydrogen bonding interaction. This modification successfully suppressed the Lewis basicity of fluoride ions, providing long‐term chemical stability (over 1000 hours) across a wide range of aprotic solvents, a broadened electrochemical stability window (−2.5–0.9 V vs. Ag+/Ag) and high ionic conductivity (1.7 mS cm−1) at room temperature. Additionally, the weaker hydrogen bonding in F−‐DPU coordination, compared to the conventional boron‐based anion acceptor (AA) strategy that relies on intensive Lewis acid‐base interactions, facilitates faster (de)fluorination kinetics at the electrode. The proposed room temperature fluoride ion batteries sustain improved electrochemical performance by pairing with the Pb‐PbF2 anode and BiF3 or Ag cathode.

Gradual release fluorine from additive to construct a stable LiF-Rich cathode electrolyte interphase for high-voltage all-solid-state lithium batteries

Gradual release fluorine from additive to construct a stable LiF-Rich cathode electrolyte interphase for high-voltage all-solid-state lithium batteries

Imidazolium-Based Ionic Liquid Electrolytes for Fluoride Ion Batteries.

The fluoride-ion battery (FIB) is a post-lithium anionic battery that utilizes the fluoride-ion shuttle, achieving high theoretical energy densities of up to 1393 Wh L-1 without relying on critical minerals. However, developing liquid electrolytes for FIBs has proven arduous due to the low solubility of fluoride salts and the chemical reactivity of the fluoride ion. By introducing a chemically stable electrolyte based on 1,3-dimethylimidazolium [MMIm] bis(trifluoromethanesulfonyl)imide [TFSI] and tetramethylammonium fluoride (TMAF), we achieve an electrochemical stability window (ESW) of 4.65 V, ionic conductivity of 9.53 mS cm -1, and a solubility of 0.67 m. The origin of this high solubility and the solvation structure were investigated using NMR spectroscopy and neutron total scattering, showing a fluoride solvation driven by strong electrostatic interactions and weak hydrogen bonding without covalent H-F character. This indicates the chemical stability of 1,3-dimethylimidazolium toward the fluoride ion and its potential as an electrolyte for high-voltage FIBs.

Shielding Fluoride Ion Basicity through Diurea Coordination for Nonaqueous Fluoride Shuttle Batteries.

The strong basicity of fluoride ions leads to detrimental nucleophilic attack on organic components in the electrolytes, such as β-hydrogen elimination reactions with organic cations and solvents, converting "naked" F- into corrosive and unstable bifluoride (HF2-) ions. These reactions significantly constrain the choice of suitable solvents and salts to develop electro(chemical) stable fluoride ion electrolytes. In this work, we replaced the triple water ligands typically present in industrialorganic fluoride salts with dual 1,3-diphenylurea (DPU) coordination via hydrogen bonding interaction. This modification successfully suppressed the Lewis basicity of fluoride ions, providing long-term chemical stability (over 1000 hours) acrossa wide range of aprotic solvents, a broadened electrochemical stability window (-2.5 ~ 0.9 V vs. Ag+/Ag) and high ionic conductivity (1.7 mS cm-1) at room temperature. Additionally, the weaker hydrogen bonding in F--DPU coordination, compared to the conventional boron-based anion acceptor (AA) strategy that relies on intensive Lewis acid-base interactions, facilitates faster (de)fluorination kineticsat the electrode. The proposed room temperature fluoride ion batteries sustain improved electrochemical performance by pairing with the Pb-PbF2 anode and BiF3 or Ag cathode.

Salt-Concentrated Electrolyte Constructing High Elasticity Modulus Interphase for Li-Rich Layered Oxide Cathode.

Stable electrolytes are urgently required for lithium-ion batteries based on lithium-rich layered oxides (LLOs), which generally suffer from fast capacity and voltage decay at high voltages up to 4.8 V. Herein, we report a salt-concentrated electrolyte consisting of 4 M lithium hexafluorophosphate (LiPF6) salt in ester solvents of fluoroethylene carbonate (FEC) and dimethyl carbonate (DMC) to alleviate the above challenges. The solvent structure in the 4 M electrolyte shows more volatile DMC integrated with Li+ and more free antioxidative FEC compared with a 1 M electrolyte, broadening the operation voltage. Simultaneously, this electrolyte endows a thin yet high elasticity modulus LiF-rich interphase on the LLOs surface, which can effectively prevent diverse side reactions and transition metal migration, consequently improving the electrochemical performance with a voltage decay of only 0.46 mV/cycle and capacity retention of 80.3% after 500 cycles. This simple and effective approach boosts the development of high-energy-density batteries using LLOs.

Green Electrolytes for Aqueous Ion Batteries: Towards High‐Energy and Low‐Temperature Applications

AbstractAqueous battery systems are increasingly recognized for their potential as environmentally friendly next‐generation energy storage solutions. However, their commercialization faces challenges due to the need for electrolytes that can operate stably at high voltages and in low‐temperatures. Traditional approaches to address these issues often involve materials that compromise the green nature. This review highlights the importance of developing environmentally friendly materials to improve the performance of aqueous electrolytes under high voltage in different types of aqueous electrolytes such as water‐in‐salt, molecular crowding electrolytes, eutectic electrolytes and cosolvents. In addition, we review advances in different types of aqueous electrolytes focused on using sustainable materials to achieve stable electrolytes at low‐temperature by suppressing water crystallization and lowering the freezing point. By integrating these innovations, we envision a future where aqueous batteries offer both high performance and eco‐friendliness, contributing significantly to the development of sustainable energy systems.

Anion Modulation: Enabling Highly Conductive Stable Polymer Electrolytes for Solid‐State Li‐Metal Batteries

Solid polymer electrolytes (SPEs) are promising ionic conductors for developing high‐specific‐energy solid‐state lithium metal batteries. However, developing SPEs with both high ionic conductivity and interfacial compatibility remains a challenge. Here, we propose a design concept of an anion‐modulated polymer electrolyte (termed AMPE) for high‐voltage Li metal batteries. Specifically, we design the AMPE by incorporating high‐voltage‐resistant and high charge density units with an anion receptor unit. The high‐voltage‐resistant and high charge density segments contribute to achieving a decent voltage tolerance of the polymer chains and ensure sufficient carrier ions. The anion receptor, represented by a boron‐containing molecule, promotes the generation of free Li+ by dissociating anion‐cation pairs. More importantly, the strong interaction between the electron‐deficient B and the TFSI− in the matrix promotes the anion reduction to form a stable anion‐derived mosaic‐like solid electrolyte interphase on the Li‐metal anode. As a result, the AMPE exhibits a high Li+ conductivity of 3.80×10−4 S cm−1 and effectively suppresses lithium dendrites, enabling an all‐solid‐state Li|AMPE|LiCoO2 cell to achieve a cycle life of 700 cycles at an operating voltage of 4.40 V. This design concept would inspire efforts to develop high‐performance SPEs for high‐specific‐energy solid‐state lithium metal batteries.

Anion Modulation: Enabling Highly Conductive Stable Polymer Electrolytes for Solid-State Li-Metal Batteries.

Solid polymer electrolytes (SPEs) are promising ionic conductors for developing high-specific-energy solid-state lithium metal batteries. However, developing SPEs with both high ionic conductivity and interfacial compatibility remains a challenge. Here, we propose a design concept of an anion-modulated polymer electrolyte (termed AMPE) for high-voltage Li metal batteries. Specifically, we design the AMPE by incorporating high-voltage-resistant and high charge density units with an anion receptor unit. The high-voltage-resistant and high charge density segments contribute to achieving a decent voltage tolerance of the polymer chains and ensure sufficient carrier ions. The anion receptor, represented by a boron-containing molecule, promotes the generation of free Li+ by dissociating anion-cation pairs. More importantly, the strong interaction between the electron-deficient B and the TFSI- in the matrix promotes the anion reduction to form a stable anion-derived mosaic-like solid electrolyte interphase on the Li-metal anode. As a result, the AMPE exhibits a high Li+ conductivity of 3.80×10-4 S cm-1 and effectively suppresses lithium dendrites, enabling an all-solid-state Li|AMPE|LiCoO2 cell to achieve a cycle life of 700 cycles at an operating voltage of 4.40 V. This design concept would inspire efforts to develop high-performance SPEs for high-specific-energy solid-state lithium metal batteries.

Room-temperature ionic liquid electrolytes for carbon fiber anodes in structural batteries

Structural batteries require thermally stable electrolytes paired with carbon fibers (CFs), which offer advantages of lightweight, high mechanical strength, and good electrical conductivity. This work evaluated various room-temperature ionic-liquids (RTILs) as compatible electrolytes for CF anodes and LiFePO4 (LFP) cathodes on CFs. This LFP/CF full-cell design eliminates Cu and Al current-collectors, potentially enhancing gravimetric energy and reducing costs. Among various RTILs, LiTFSI in N-propyl-N-methylpyrrolidinium (PYR13) – bis(fluorosulfonyl)imide (FSI) offered promising LFP/CF full-cell performances, attributed to the formation of solid electrolyte interphase (SEI) layer on the CF anode with components such as Li2Sx, Li2S–SO3, LiF, LixFy and F–SO2, identified through X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Electrochemical impedance spectroscopy (EIS) and distribution of relaxation times (DRT) analyses further confirmed the electrochemical stability of the SEI layer on CF anodes. The LFP/CF cell delivered an initial capacity of 119 mAh/g and relatively high Coulombic efficiency when using the 1 M LiTFSI in PYR13-FSI. CF cycled in different electrolytes exhibit varying mechanical properties with up to 10.08 % loss in tensile strength, which may be related to CF surface degradation during cycling. The 1 M LiTFSI in PYR13-FSI is non-flammable, offering a significant thermal safety. This work successfully demonstrated the significant potential of 1 M LiTFSI in PYR13-FSI RTILs, which enables the use of CF as both an anode active material and cathode current collector for structural battery applications.

Cellulose-based water-in-salt ZnBr2 hydrogels with multiple functions for energy storage devices

A new simple preparation method for water-in-salt-type cellulose hydrogels filled with ZnBr2 is reported. The ZnBr2 hydrogel electrolyte can be applied to zinc-ion hybrid supercapacitors and Zn-Br interfacial batteries. The water-in-salt ZnBr2 hydrogel serves as a stable electrolyte for good electrochemical performance in zinc-ion hybrid supercapacitors without redox reactions and can participate in the charging/discharging process of the Zn‒Br interfacial battery through the redox reaction of halogen anions. The assembled zinc-ion hybrid supercapacitor exhibits a specific capacitance of 241.8 F g-1 at 0.5 A g-1. Furthermore, after a 10000-cycle-long charging/discharging test at 5 A g-1, the coulombic efficiency is found at nearly 100%. The interfacial battery reaches the highest energy efficiency of 66% at a current density of 3 mA cm-2 at 0–1.8 V and displays a good cycle life with an 88% average coulombic efficiency at 3 mA cm-2. This work expands the application of hydrogels and provides new possibilities for optimizing the high performance of electrolytes.

Design Lithium Exchanged Zeolite Based Multifunctional Electrode Additive for Ultra‐High Loading Electrode Toward High Energy Density Lithium Metal Battery

AbstractThe practicalization of a high energy density battery requires the electrode to achieve decent performance under ultra‐high active material loading. However, as the electrode thickness increases, there is a notable restriction in ionic transport in the electrodes, limiting the diffusion kinetics of Li+ and the utilization rate of active substances. In this study, lithium‐ion‐exchanged zeolite X (Li‐X zeolite) is synthesized via Li+ exchange strategy to enhance Li+ diffusion kinetics. When incorporated Li–X zeolite into the ultra‐high loading cathodes, it possesses i) high electron conductivity with a uniform network by reducing tortuosity, ii) decent ion conductivity attributes to modulated Li+ diffusivity of Li‐X and iii) high elasticity to prevent particle‐level cracking and electrode‐level disintegration. Moreover, Li–X zeolite at the solid/liquid interface facilitates the formation of a stable cathode electrolyte interface, which effectively suppresses side reactions and mitigates the dissolution of transition cations. Therefore, an ultra‐high loading (66 mg cm−2) cathode is fabricated via dry electrode technology, demonstrating a remarkable areal capacity of 12.7 mAh cm−2 and a high energy density of 464 Wh kg−1 in a lithium metal battery. The well‐designed electrode structure with multifunctional Li–X zeolite as an additive in thick cathodes holds promise to enhance the battery's rate capability, cycling stability, and overall energy density.

Tailoring eco-friendly siloxane-based electrolytes for high-performance lithium–sulfur batteries

Lithium–sulfur batteries (LSBs), with their ultra-high theoretical energy density (2600 Wh kg−1), are considered one of the most attractive high-energy batteries. However, the “shuttling effect” of polysulfides and the uncontrolled growth of lithium (Li) dendrites pose significant challenges to the practical implementation of LSBs. Herein, a lightweight and eco-friendly diethoxydimethylsilane (DEMS) is chosen as a multi-functional solvent for LSBs. The low polarity of DEMS promotes the “solid–solid” conversion of sulfurized polyacrylonitrile (SPAN) during charge–discharge processes, eliminating the shuttle effect of polysulfides. Moreover, the DEMS-based electrolyte enables highly reversible Li plating/stripping processes across a wide temperature range spanning from −20 to 60 °C. As a result, the Li/SPAN batteries using the DEMS electrolyte exhibit excellent cyclic stability at 0.2 C with retainable capacities of 524.4 mAh/g after 200 cycles, 598.8 mAh/g after 100 cycles, and 318.6 mAh/g after 50 cycles at 26, 60 and −20 °C, respectively. This study aims to identify low-cost and highly stable electrolytes through solvent screening to enhance the electrochemical performance of LSBs.

Transforming Zinc-Ion Batteries with DTPA-Na: A Synergistic SEI and CEI Engineering Approach for Exceptional Cycling Stability and Self-Discharge Inhibition.

Aqueous zinc-ion batteries (ZIBs) hold immense potential for large-scale energy storage, but their practical implementation faces significant challenges related to the zinc anode, including dendrite formation, corrosion, and hydrogen evolution. This study addresses these challenges by introducing diethylenetriamine pentaacetate sodium salt (DTPA-Na) as a novel electrolyte additive. DTPA-Na exhibits a unique dual functionality, enabling the formation of a robust, multi-layered solid electrolyte interphase (SEI) on the zinc anode and a stable cathode electrolyte interphase (CEI) on the MnOOH cathode. The engineered SEI effectively suppresses interfacial side reactions, facilitates uniform zinc deposition, and mitigates dendrite growth, while the CEI inhibits MnOOH dissolution and detrimental cathode side reactions. This synergistic SEI/CEI engineering approach significantly enhances ZIB performance, achieving remarkable cycling stability and self-discharge inhibition, as evidenced by the extended lifespan of Zn||Zn symmetrical cells (4400 hours at 0.5 mA/cm2) and the exceptional capacity retention of Zn||MnOOH full cells after prolonged rest (98.61 % after 720 hours).

Chemical Roadmap toward Stable Electrolyte–Electrode Interfaces in All-Solid-State Batteries

Chemical Roadmap toward Stable Electrolyte–Electrode Interfaces in All-Solid-State Batteries

Exceptionally Stable Polymer Electrolyte Membrane Fuel Cells Enabled by One-Pot Sequential Atomic Layer Deposition of Titania and Platinum

Exceptionally Stable Polymer Electrolyte Membrane Fuel Cells Enabled by One-Pot Sequential Atomic Layer Deposition of Titania and Platinum

Acidic "Water-in-Salt" Electrolyte Enables a High-Energy Symmetric Supercapacitor Based on Titanium Carbide MXene.

Titanium carbide MXene, Ti3C2Tx, exhibits ultrahigh capacitance in acidic electrolytes at negative potentials yet poor stability at positive potentials, resulting in low-energy densities for Ti3C2Tx-based symmetric supercapacitors. Utilizing "water-in-salt" electrolytes has successfully expanded the stable operation potential window of MXenes. However, this advancement comes at the cost of sacrificing their high capacitance in acidic electrolytes. In this work, we report an acidic "water-in-salt" (AWIS) electrolyte composed of sulfuric acid and saturated lithium halide, which effectively doubled the energy density of the Ti3C2Tx-based symmetric supercapacitor compared to those with bare acidic electrolytes. Specifically, the AWIS electrolyte successfully expanded the voltage window of the symmetric device to 1.1 V. A high specific capacitance of 112.34 F g-1 (at 10 mV s-1) was obtained due to the presence of proton redox. As a result, the symmetric device achieved a high-energy density of 19.1 Wh kg-1 and a high capacitance retention of 96.3% after 10,000 cycles. This work demonstrates the importance of designing stable and redox-active electrolytes for high-energy MXene-based symmetric supercapacitors.

Ethyl Isopropyl Sulfone Modulating to Achieve Stable High-Voltage Electrolyte for Lithium-Ion Batteries.

The demand for efficient large-scale energy storage necessitates high-energy-density batteries, making research on high-voltage electrolytes particularly important. In this article, ethyl isopropyl sulfone (ES), which has a high dielectric constant, is added to traditional carbonate-based electrolyte solvents and analyzed. Based on calculated and analyzed results, different proportions of ES are added to the conventional carbonate-based electrolyte. The high-voltage performance, the influence on the surface of the electrode, the active material structure after cycling, the electrochemical behavior, and the impedance of the electrode were studied systematically. As a result, ES addition is applied in high-voltage lithium-ion batteries and exhibits excellent electrochemical properties. These results will provide support for the research and application of sulfone additives in increasing the decomposition voltage of lithium-ion battery electrolytes and improving battery cycle stability.

Preparation and characterisation of IPMC brakes modified with composite electrodes performance

Ionic Polymer Metal Composite (IPMC) can be used as flexible actuators and sensors in the fields of bionic machinery and medical devices. However, IPMC still suffer from poor actuation performance and high cost of electrode preparation in practical applications. Optimisation of electrodes and use of novel assembly processes are expected to solve these problems. In this paper, low-dimensional nanocarbon materials were used to modify the Nafion membrane. Appropriate amounts of carbon nanotubes and carbon black were weighed and dispersed in chitosan and acetic acid to form a stable electrolyte. A new IPMC was prepared by bonding carbon nanotube and carbon black films on the Nafion membrane using the hot pressing method. Scanning electron microscope images showed that the hybrid films composed of carbon nanotubes and carbon black were successfully hot pressed onto the surface of the Nafion membrane and the hybrid electrode layer composed of carbon nanotubes and carbon black was more homogeneous and densely packed. The results of driving performance tests show that the hybrid electrode-modified IPMC has excellent driving performance, with a maximum output displacement of 9.2 mm and a maximum output force of 9.9 mN at a voltage of 5.0 V. These results are 1.07 and 1.14 times higher than those of the carbon nanotube IPMC and 1.74 and 1.70 times higher than those of the carbon black IPMC under the same conditions, respectively.