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Current potassium‐ion batteries (PIBs) are limited in safety and lifetime owing to the lack of suitable electrolyte solutions. To address these issues, herein, we report an innovative non‐flammable electrolyte design strategy that leverages an optimal moderate solvation phosphate‐based solvent which strikes a balance between solvation capability and salt dissociation ability, leading to superior electrochemical performance. The formulated electrolyte simultaneously exhibits the advantages of low salt concentration (only 0.6 M), low viscosity, high ionic conductivity, high oxidative stability, and safety. Our electrolyte also promotes the formation of self‐limiting inorganic‐rich interphases at the anode surface, alongside robust cathode‐electrolyte interphase on iron‐based Prussian blue analogues, mitigating electrode/electrolyte side reactions and preventing Fe dissolution. Notably, the PIBs employing our electrolyte exhibit exceptional durability, with 80 % capacity retention after 2,000 cycles at high‐voltage of 4.2 V in a coin cell. Impressively, in a larger scale pouch cell, it maintains over 81 % of its initial capacity after 1,400 cycles at 1 C‐rate with high average Coulombic efficiency of 99.6 %. This work represents a significant advancement toward the realization of safe, sustainable, and high‐performance PIBs. [ABSTRACT FROM AUTHOR]

Rechargeable Zinc batteries (RZBs) are considered a potent competitor for next‐generation electrochemical devices, due to their multiple advantages. Nevertheless, traditional aqueous electrolytes may cause serious hazards to long‐term battery cycling through fast capacity fading and poor Coulombic efficiency (CE), which happens due to complex reaction kinetics in aqueous systems. Herein, we proposed the novel adoption of the protic amide solvent, N‐methyl formamide (NMF) as a Zinc battery electrolyte, which possesses a high dielectric constant and high flash point to promote fast kinetics and battery safety simultaneously. Dendrite‐free and granular Zn deposition in Zn‐NMF electrolyte assures ultra‐long lifespan of 2000 h at 2.0 mA cm−2/2.0 mAh cm−2, high CE of 99.57 %, wide electrochemical window (≈3.43 V vs. Zn2+/Zn), and outstanding durability up to 10.0 mAh cm−2. This work sheds light on the efficient performance of the protic non‐aqueous electrolyte, which will open new opportunities to promote safe and energy‐dense RZBs. [ABSTRACT FROM AUTHOR]

Asymmetric supercapacitors (ASCs), which combine the advantages of electric double-layer capacitors and pseudocapacitors, have attracted more and more research interest. However, the performance of water-based ASCs often faces the challenge of electrolyte freezing at low temperatures. To resolve the problem, a ternary deep eutectic solvent (DES) with an eutectic point of less than -100 °C was first prepared. After the DES was integrated into a polymer matrix composed of microcrystalline cellulose (MCC), hydroxyethyl cellulose (HEC), and poly(vinyl alcohol) (PVA), a flexible and non-flammable eutectogel was fabricated. The optimized eutectogel not only exhibited an ionic conductivity of 23.4 mS cm -1 even at -20 °C, but also displayed a tensile strength value of about 0.37 MPa and an elongation value at break of nearly 600 %. The ASC with a eutectogel demonstrated a high voltage window of 0-1.8 V, an energy density of 15.13 Wh kg -1 at a power density of 87.52 W kg -1 , and fantabulous cycling stability with ∼90 % capacitance retention after 5000 cycles. The flexible ASC with such a eutectogel could work well in a wide temperature range from -20 to 60 °C. It is expected that this work could present valuable insights for the development of wide-temperature gel polymer electrolytes in ASC applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

With the lightest green structural material for 21st century, a significant weight reduction effect was expected to solve the lightweight problem in aerospace and other fields. However, the material's poor mechanical properties and flammability limited its widely application in such fields. In this paper, the GWK series alloys (Mg-5.3Gd-4.11Y-0.13Zr, Mg-5.5Gd-4.22Y-0.19Zr, and Mg-5.46Gd-4.02Y-0.20Zr, in wt.%) were designed, and we explored the effect of alloy composition and process on the microstructure and properties of GWK series alloys subject to casting, homogenization, extrusion, ageing and ignition. The result show that Mg-5.3Gd-4.11Y-0.13Zr alloy after T4 treatment at 500 °C/6 h obtains an excellent solid solution effect. In addition, the aged alloy shows a good balance of mechanical properties, a tensile strength of 405 MPa, yield strength of 275 MPa, as well as elongation of 8.12%, and excellent non-flammability. [ABSTRACT FROM AUTHOR]

Boehmite [bey-mahyt] is a unique aluminum oxide hydroxide nanostructure. It consists of nanosheets of octahedral aluminum ions with surface hydroxyl groups. Owing to exceptional reinforcing behavior, boehmite nanoparticles have gained immense attention as polymeric nanofillers. Essential matrices used with the boehmite based nanocomposites include poly(methyl methacrylate), polyethylene, polypropylene, polyamide, epoxy, and other polymers. In this review, all-inclusive considerations on the design, morphology, mechanical, thermal, electrical, ion conducting, flame retardancy, electrochemical, and other physical properties, and advances related to the polymer/boehmite nanocomposites are presented. The polymer/boehmite nanocomposites have been employed for the membranes (water filtration/dye removal), coatings (anti-corrosion/self-healing), Li-ion batteries, and non-flammability purposes. [ABSTRACT FROM AUTHOR]

High thermal conductivity, high strength and non-flammability have successfully been achieved concurrently for the first time in Mg-4.5Al-2.5Ca, Mg-5Al-3Ca, Mg-6Al-4Ca, and Mg-4Al-2Ca-0.03Be (at%) alloys, which are produced by hot extrusion of the heat-treated cast alloys. These alloys consist of α-Mg, and C36, C14 and C15 compounds, and exhibit a high thermal conductivity of 111-119Wm-1K-1, a high ignition temperature of 1343-1408K and a high tensile yield strength of 318-363 MPa. [ABSTRACT FROM AUTHOR]

With the lightest green structural material for 21st century, a significant weight reduction effect was expected to solve the lightweight problem in aerospace and other fields. However, the material’s poor mechanical properties and flammability limited its widely application in such fields. In this paper, the GWK series alloys (Mg-5.3Gd-4.11Y-0.13Zr, Mg-5.5Gd-4.22Y-0.19Zr, and Mg-5.46Gd-4.02Y-0.20Zr, in wt.%) were designed, and we explored the effect of alloy composition and process on the microstructure and properties of GWK series alloys subject to casting, homogenization, extrusion, ageing and ignition. The result show that Mg-5.3Gd-4.11Y-0.13Zr alloy after T4 treatment at 500 °C/6 h obtains an excellent solid solution effect. In addition, the aged alloy shows a good balance of mechanical properties, a tensile strength of 405 MPa, yield strength of 275 MPa, as well as elongation of 8.12%, and excellent non-flammability.

Polyhedral oligomeric silsesquioxane (POSS) is an inorganic-organic nanostructure. POSS nanocage possesses silica core and organic functionalities at corners. POSS has been familiarized with various thermoplastic and thermosetting polymeric matrices. Polyurethane is an imperative polymer used with POSS nanofiller through physical mixing or chemical interaction methods. Inclusion of POSS may advance thermal, mechanical, rheological, crystallinity, morphological, non-flammability and other characteristics of polyurethane nanocomposite. This state-of-the-art article précises design and development of polyurethane/POSS nanocomposite. Versatility of POSS and compatibilization effect have been deliberated on properties and performance of polyurethane. Recent progress of polyurethane/POSS nanocomposite toward non-flammability, anti-corrosion and biomedical relevance has been conversed. [ABSTRACT FROM AUTHOR]

Rechargeable alkali metal (i.e., lithium, sodium, potassium)‐based batteries are considered as vital energy storage technologies in modern society. However, the traditional liquid electrolytes applied in alkali metal‐based batteries mainly consist of thermally unstable salts and highly flammable organic solvents, which trigger numerous accidents related to fire, explosion, and leakage of toxic chemicals. Therefore, exploring non‐flammable electrolytes is of paramount importance for achieving safe batteries. Although replacing traditional liquid electrolytes with all‐solid‐state electrolytes is the ultimate way to solve the above safety issues, developing non‐flammable liquid electrolytes can more directly fulfill the current needs considering the low ionic conductivities and inferior interfacial properties of existing all‐solid‐state electrolytes. Moreover, the electrolyte leakage concern can be further resolved by gelling non‐flammable liquid electrolytes to obtain quasi‐solid electrolytes. Herein, a comprehensive review of the latest progress in emerging non‐flammable liquid electrolytes, including non‐flammable organic liquid electrolytes, aqueous electrolytes, and deep eutectic solvent‐based electrolytes is provided, and systematically introduce their flame‐retardant mechanisms and electrochemical behaviors in alkali metal‐based batteries. Then, the gelation techniques for preparing quasi‐solid electrolytes are also summarized. Finally, the remaining challenges and future perspectives are presented. It is anticipated that this review will promote a safety improvement of alkali metal‐based batteries. [ABSTRACT FROM AUTHOR]

In this study, it was aimed to investigate the usability of compounds in inorganic structure and the effect of these compounds used in composites on the mechanical properties of composites in order to give fire retardant properties to glass fiber reinforced polyester composites (CTP). Antimony trioxide (Sb2O3), aluminum hydroxide (Al(OH)3) and zinc borate (2ZnO3.BrO3.3H2O) were added by different proportions (5%, 10%, 15%, 20%, 25%, 30%) to resin blends to improve the non-flammability of the composites. In experimental study, the combustion behavior of the doped CTP composites produced using different inorganic compounds was determined by international combustion standards ASTM D-635, ASTM D-3801 and ASTM D-5048. In addition, thermo gravimetric analysis (TGA) was applied in order to determine the thermal behavior of the produced GRP composites due to temperature increase and tensile test were applied according to ASTM 638-14.As a result, when the flame retardant additive ratio is 15% or more in the GRP composites, the hand lay production became difficult due to the increase in viscosity. According to ASTM D-3801, when 30% AH (Aluminum hydroxide) is used, non-combustible material in V1 class can be produced. All FRP composites containing flame retardants were included in the HB (Horziontal burning) slowly burning material class. Flame retardant use generally reduced the tensile strength of GRP composites, but it was found that 10% increase in AT (Antimony trioxide)-doped CTPs. [ABSTRACT FROM AUTHOR]

The effect of Al content on the texture evolution and recrystallization behavior of the non-flammable Mg sheet alloys containing Ca and Y was investigated in this study. With a decrease in the Al content from 3 wt.% to 1 wt.%, the amounts of the other alloying elements dissolved in the matrix, especially Ca, are increased. The increase of the alloying elements in a solid solution brought out the retarded recrystallization and weakened texture with the basal poles tilted toward the sheet transverse direction. Extension twinning activity increased when Al content with decreasing, resulting in the texture broadening towards the sheet transverse direction in the as-rolled sheets. The textures of the AZXW1000 and AZXW2000 sheets weaken uniformly in all sample directions during annealing, while the AZXW3000 sheet shows less weakening of the rolling direction split component. The texture weakening of the alloys with lower Al contents is attributed to the retarded recrystallization caused by the larger amount of the dissolved Ca solutes. Based on the non-basal texture and relatively stable grain structure, the Mg alloy sheet containing a relatively small amount of Al is advantageous to improve the formability.

A new Mg alloy with the composition of Mg-8Al-0.3Zn-0.1Mn-0.3Ca-0.2Y was successfully fabricated by a low-temperature, low-speed indirect extrusion process. The extruded alloy showed excellent mechanical properties, i.e., a tensile yield strength of 379.3 MPa, ultimate tensile strength of 421.7 MPa, elongation of 11.3%, and yield asymmetry of 0.95, as well as a very high chip ignition temperature of 820 °C. The outstanding mechanical properties are attributed to the microstructural characteristics of the extruded alloy, that is, (i) grain boundary strengthening by fine recrystallized grains, (ii) precipitation hardening by abundant fine Mg 17 Al 12 precipitates, and (iii) strain hardening by the deformed non-recrystallized region with a strong basal texture that is unfavorable for basal slip during tension. Electron backscatter diffraction results showed that no twinning occurred in the recrystallized grains, which had a very small size of approximately 800 nm, whereas {10–12} twins were formed in the non-recrystallized grains even at low compressive stress, which consequently increased the yield asymmetry. [ABSTRACT FROM AUTHOR]

The anode properties of Nb-doped rutile TiO 2 electrodes were investigated in an ionic liquid electrolyte comprised of N -methyl- N -propylpyrrolidinium cation and bis(fluorosulfonyl)amide anion for use in a safe Na-ion battery. Although the electrolyte's conductivity was lower than that of a conventional organic electrolyte at 30 °C, it showed high conductivity comparable to that of the organic electrolyte at 60 °C. The Nb-doped TiO 2 electrode showed excellent cyclability in the ionic liquid electrolyte at 60 °C: a high capacity retention of 97% was observed even at the 350th cycle, which is comparable to value in the organic electrolyte (91%). In a non-flammability test in a closed system, no ignition was observed with the ionic liquid electrolyte even at 300 °C. These results indicate that combination of a Nb-doped TiO 2 anode and ionic liquid electrolyte gives not only an excellent cyclability but also high safety for a Na-ion battery operating at a temperature below the sodium's melting point of 98 °C. [ABSTRACT FROM AUTHOR]

The issue of the safety of Li-ion batteries is becoming more critical with the increase in their size for applications in large energy storage devices, such as hybrid electric vehicles (HEVs), and energy storage systems (ESSs) for smart grids. The thermal runaway of Li-ion batteries is considered to be caused by their flammable components, such as the volatile carbonate solvents of electrolytes. Room temperature ionic liquids (RTILs) have recently received much attention because of their characteristics of non-flammability and non-volatility. In addition, RTILs show high ionic conductivity and a wide electrochemical stability window. Therefore, RTIL-based electrolytes are considered one of the most promising candidates to improve the safety of Na-ion, as well as Li-ion batteries; indeed, RTIL-based electrolytes have shown excellent improvements in terms of thermal stability and electrochemical performance. This review provides a comprehensive overview of selected RTIL materials, including their physicochemical and electrochemical properties. Moreover, we discuss the failure mechanisms of certain RTIL-based electrolytes with various electrodes to suggest alternative strategies for improving their electrochemical performance. [ABSTRACT FROM AUTHOR]

Today, the requirement for clean, highly efficient, and safe energy seems to be higher and higher due to non-renewable energy and pollution of the environment. At this moment, lithium-ion batteries (LIBs) look like a reliable solution for this dilemma since they have huge energy density. However, the flammability of the conventional electrolyte used in the LIBs is one of critical disadvantages of LIBs, which compromises the safety issue of LIBs. Herein, we reported a non-flammable zwitterionic ionic liquid-based electrolyte named TLPEC, which was fabricated by simply mixing a novel zwitterionic ionic liquid TLP (93 wt%) and ethylene carbonate (EC, 7 wt%). The TLPEC electrolyte exhibited a wide electrochemical potential window of 1.65–5.10 V and a robust ionic conductivity of 1.0 × 10−3 S cm−1 at 20 °C, which renders TLPEC to be a suitable electrolyte for LIBs with enhanced safety performance. The LIBs, with TLPEC as the electrolyte, exhibited an excellent performance in terms of excellent rate capability, cycling stability, and high specific capacity at 25 and 60 °C, which were attributed to the stability and high ionic conductivity of TLPEC electrolyte during cycling as well as the excellent interface compatibility of TLPEC electrolyte with lithium anode. [ABSTRACT FROM AUTHOR]

The effect of Al content on the texture evolution and recrystallization behavior of the non-flammable Mg sheet alloys containing Ca and Y was investigated in this study. With a decrease in the Al content from 3 wt.% to 1 wt.%, the amounts of the other alloying elements dissolved in the matrix, especially Ca, are increased. The increase of the alloying elements in a solid solution brought out the retarded recrystallization and weakened texture with the basal poles tilted toward the sheet transverse direction. Extension twinning activity increased when Al content with decreasing, resulting in the texture broadening towards the sheet transverse direction in the as-rolled sheets. The textures of the AZXW1000 and AZXW2000 sheets weaken uniformly in all sample directions during annealing, while the AZXW3000 sheet shows less weakening of the rolling direction split component. The texture weakening of the alloys with lower Al contents is attributed to the retarded recrystallization caused by the larger amount of the dissolved Ca solutes. Based on the non-basal texture and relatively stable grain structure, the Mg alloy sheet containing a relatively small amount of Al is advantageous to improve the formability. [ABSTRACT FROM AUTHOR]

Safety concerns impede the deployment of Li-metal batteries, while the highly flammable electrolytes make main contribution to the hazard caused by the reactive Li with electrolytes. Fire-extinguishing electrolytes do exist, but their introductions into the batteries have generally resulted in cycle performance trade-offs. In this work, we report a new electrolyte that consists of 1 M lithium hexafluorophosphate dissolved in a single solvent of vinylethylene carbonate (VEC), enabling Li-metal batteries with the most reliability in terms of high safety, long cycle life and practical scale-up among the up-to-date strategies. Combining theoretical calculations with physical and electrochemical characterizations, we demonstrate that this new electrolyte is highly flame-retardant, thanks to the strong combination of VEC with hydrogen and hydroxide radicals, and provides Li-metal anode with excellent cycle stability, attributed to easy desolvation of Li ions in VEC and unique interphase chemistry that consists of inorganic Li 2 CO 3 underneath and organic –(CH 2 –CH 2 O) 2 - species on the top, originated from VEC reduction. Considering the low cost of VEC, this VEC-based electrolyte makes it possible for Li-metal batteries to be applied practically in large scale. VEC-based electrolyte enables Li-metal batteries more reliable than state-of-the-art approaches in terms of safety, cyclic stability and rate capacity. Image 1 • Highly safe and cyclabe Li-metal batteries are accomplished with a novel LiPF 6 /VEC electrolyte. • VEC is highly flame-retardant due to its strong combination of VEC with H⋅ and OH⋅ radicals, ensuring the highly safe batteries. • A unique interphase of underneath inorganic Li 2 CO 3 and top organic –(CH 2 –CH 2 O) 2 - species is established by VEC reduction. • High cyclability of the batteries is ensured with then unique interphase chemistry and the easy desolvation of Li ions in VEC. [ABSTRACT FROM AUTHOR]

• Non-flammable electrolyte with TMP and F-EPE improves the safety of SIB. • TMP/F-EPE electrolyte stabilizes the interface of NFM cathode during all processes. • The cycling life of NFM/HC pouch cell increases by using TMP/F-EPE electrolyte. Despite their beneficial effect on battery safety, non-flammable electrolytes often have an adverse side effect on the electrochemical performance of lithium and sodium ion batteries due to their poor compatibility with the electrodes. In this paper, we report a new non-flammable electrolyte consisting of trimethyl phosphate (TMP) and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (F-EPE) as non-flammable solvents and fluoroethylene carbonate (FEC) as additive with different concentration of Na salts, and a EC-DEC-FEC electrolyte was also prepared as baseline electrolyte. The flammability and non-flammability of the prepared electrolytes was tested. It is shown that the prepared electrolyte not only increases the capacity (129.9 vs. 122.5 mAh g−1 of baseline electrolyte) of NaNi 1/3 Fe 1/3 Mn 1/3 O 2 (NFM) cathode but also stabilizes the cyclability (70.8% retention after 500 cycles) of NFM/HC (HC: hard carbon) pouch cells. The dissolution of pristine NaNi 1/3 Fe 1/3 Mn 1/3 O 2 cathode material in different solvents and electrolytes, and the XPS patterns of the cycled NFM cathode in the prepared electrolytes were also studied to understand the capacity fading mechanism. These results indicate that this new non-flammable electrolyte holds great potential for application in rechargeable sodium-ion batteries. [ABSTRACT FROM AUTHOR]