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The controls of proton transfer through membranes involve fundamental properties of chemical energy conversion in industrial devices as well as living systems. In particular, ion-exchange membranes are generally used as superior proton conductors for polymer electrolyte fuel cells (PEFC) due to the fluidic nature of water, although the cell operation above the boiling point (>100 degrees C) has been considered to provide a higher efficiency and an easier humidity management. We show that biomembranes consisting of uracil and chitin phosphate have large anhydrous proton conductivities over a wide temperature range from room temperature to 160 degrees C with sufficient thermal stabilities. Water-free conductivities exceeding 10(-3) S cm(-1) have been obtained in the elastic polymeric material, and the fuel cell employing the biomembrane as an electrolyte exhibited a stable current generation under non-humidified H2/O2 conditions at 160 degrees C.

3D printing technologies have been adapted to enable the fabrication of lithium-ion batteries (LIBs), allowing flexible designs such as micro-scale 3D shapes. Here, we demonstrate 3D-printable gel electrolytes, printed at room temperature. The electrolyte gel solidified by UV irradiation maintains its structural integrity and high lithium-ion conductivity, enabling fully 3D-printed quasi-solid-state LIBs. [ABSTRACT FROM AUTHOR]

Solidified lithium conducting hybrid electrolyte is designed and processed to realize the large scale and flexible solid state Li battery satisfying energy capability and safety issue. This paper presents a solidified inorganic-organic hybrid electrolyte to obtain commercially-acceptable ionic conductivity and a stable electrochemical window to prevent electrolyte decomposition in Li ion batteries. Li 3 PO 4 coated with solidified [Li][EMI][TFSI] ionic liquid is developed as hybrid electrolyte material. The material has high electrochemical stability on a high-voltage cathode and metallic anode, and the solid electrolyte has high ionic conductivity. This Li 3 PO 4 -[Li][EMI][TFSI] hybrid electrolyte has the advantages of long-term operation, safety and flexibility, so it may be suitable for use in high-voltage cathodes and Li anode. [ABSTRACT FROM AUTHOR]

Quasi-solid-state electrolyte consisting of a pseudo-ternary system, RTILs - Li-TFSA - fumed silica nanoparticles, were prepared for use as electrolytes of the all-solid-state lithium rechargeable battery. EMI-TFSA, DEME-TFSA and PP13-TFSA were chosen as RTIL solvents. It was found that the pseudo-ternary composites had liquid-like high ionic conductivity as well as self-diffusion coefficients in spite of the solid-like appearances regardless of RT1L solvent species. Stability of the quasi-solid-state electrolytes to lithium electrodes was investigated by lithium symmetric cells with ac and dc techniques. All-solid-state bulk cells were assembled and the charge - discharge characteristics were evaluated. A stable charge - discharge cycles could be performed with high cathode utilization ratios such as above 85% with comparatively lower c-rates. At higher c-rates, the discharge capacities of our all-solid-state cells using the quasi-solid-state electrolytes are smaller than that using a conventional organic electrolyte with a separator. This suggests that the power density of our all-solid-state cells is essentially limited by slow lithium-ion transport similarly to RTIL - Li-salt mixtures. Based on the above results, the correlation between the charge - discharge cycling performance of our all-solid-state cells and the stabilities of the quasi-solid-state electrolytes were discussed. [ABSTRACT FROM AUTHOR]

We have fabricated solidified electrolytes by using an ionic liquid (BMI TFST) and TiO2; the electrolyte materials exhibit a high conductivity of 10-2 S cm-1 at intermediate temperatures due to self-assembled ionic transport channels. [ABSTRACT FROM AUTHOR]

Abstract: Nano-sized Li4Ti5O12 powders with high dispersivity were fabricated by a sol–gel process using P123 as surfactant, which exhibited much better high rate performance towards Li+ insertion/extraction as compared to the densely aggregated Li4Ti5O12 particles although the primary grain sizes of both samples were almost the same. The Li4Ti5O12 electrode prepared from the well-dispersed nanopowders can preserve 88.6% of the capacity at 0.1Ag−1 when being cycled at 1Ag−1, which is obviously higher than that of the densely aggregated sample, in which only 30% capacity can be retained. By improving the dispersivity, the specific surface area of the Li4Ti5O12 nanoparticles, hence the electrode–electrolyte contact area was increased; meanwhile, more homogeneous mixing of the active materials with carbon black was achieved. All these factors might have resulted in the better high rate performance. [Copyright &y& Elsevier]

We have fabricated solidified electrolytes by using an ionic liquid (BMI TFST) and TiO2; the electrolyte materials exhibit a high conductivity of 10-2 S cm-1 at intermediate temperatures due to self-assembled ionic transport channels. [ABSTRACT FROM AUTHOR]

The article reports on the synthesis of a self-ordered, crystalline glass, mesoporous nanocomposite with high proton conductivity. Mesoporous inorganic materials have a pore size range of 2-50 nm and have several properties that may be beneficial for their use as possible solid-state electrolyte alternatives. Mesoporous materials as a proton conducting electrolyte for fuel cells have been reported. At the intermediate temperature region, proton conductivity decreases by the evaporation of water because the origin of proton conduction in mesoporous material is based on the physisorbed water in the pore.

Abstract: Polyacrylonitrile sulfide (PAN-S) was synthesized for use as a positive electrode of a lithium rechargeable battery. To assemble the lithium rechargeable battery with an all-solid-state cell configuration, we also prepared a quasi-solid-state electrolyte consisting of a room temperature ionic liquid (RTIL)-like equimolar complex of tetraethylene glycol dimethyl ether (tetraglyme, G4)–lithium bis(trifluoromethanesulfonyl)amide (Li-TFSA) and fumed silica nanoparticles. The lithium rechargeable battery with the PAN-S positive electrode, quasi-solid-state electrolyte and lithium negative electrode showed high capacity and good cycle performance. The 2nd and 50th discharge capacities were 450 and 390mAhg−1, respectively, with nearly 100% Coulombic efficiency without remarkable capacity fade during the operation. [Copyright &y& Elsevier]

Abstract: Quasi-solid-state electrolytes (QSEs), consisting of pseudo-ternary system, i.e., room temperature ionic liquid (RTIL)-lithium bis(trifluoromethanesulfonyl)amide (Li-TFSA)-fumed silica nano particles, were prepared for use as electrolytes in bulk-type all-solid-state cell configuration lithium-sulfur rechargeable batteries. Regardless of the high concentration of RTIL-Li-salt mixtures with fumed silica nano particles, i.e., 80-90% volume ratio, the composites were white powders. Further blending with 5wt% polytetrafluoroethylene (PTFE) powder caused the composite powders to become transparent sheets of 30-200 μm in thickness. The electrolyte sheets exhibited liquid-like high apparent conductivities regardless of their solid-like appearance. Sulfur utilization ratios were enhanced using conductive additives with high specific surface areas. Cells with notable performance were successfully assembled after the optimization of the RTIL solvent composition, electrolyte thickness, and conductive additive species. The initial discharge capacity was 1100mAh g−1 at 0.05 C. After 45 discharge-charge cycles, the discharge capacity was still 690mAhg−1. This performance is comparable to lithium-sulfur cells that use the RTIL-Li-salt liquid electrolytes. [Copyright &y& Elsevier]

Abstract: Even though the use of solid-state electrolytes for all-solid-state lithium battery applications has been a topic of great interest, an optimal material for this purpose has not been found. On the basis of the fact that ionic liquids are solidified at oxide particle surfaces and become quasi-solid materials, we previously fabricated a new lithium-ion-conducting solid electrolyte material comprising silica nano-particles and an ionic liquid that exhibited high ion conductivity comparable to the bulk ionic liquid. In the current study, this electrolyte was applied in the fabrication of an all-solid-state lithium secondary battery cell, by using three-dimensional structural cathode mixing the solid electrolyte and a cathode material (LiCoO2). The most important feature of the newly developed cell is that it was fabricated using thick films. There are no prior reports of all-solid-state secondary batteries employing thick films that exhibit high capacity. In this design, all of the cathode active materials could make contact with the electrolyte and the electron-conducting material despite the all-solid-state nature of the device. As a result, we have succeeded in the fabrication of an all-solid-state lithium secondary battery exhibiting high capacity of 126mAhg−1, nearly equal to theoretical capacity 138mAhg−1, despite the use of a micrometer order thick-film device. This study paves the way for the application of a new approach to the all-solid-state lithium secondary battery design. [Copyright &y& Elsevier]

Abstract: Anhydrous nafion-benzimidazole (bz) blend membranes were prepared by room temperature and autoclave solution processing. The physico-chemical properties of anhydrous nafion-bz blend membranes using different solution processing were investigated by TG-DTA, dynamic elastic modulus, XRD, SAXS, and proton conductivity. The nafion-bz blend membrane using autoclave solution processing improved the properties such as a flexibility, density, homogeneity and dynamic elastic modulus, while the crystalline in a macroscopic crystal structure and proton conductivity was nearly the same. [ABSTRACT FROM AUTHOR]

Abstract: Ionic conduction properties of layered double hydroxides (LDHs), [Mg(1 − x)Al(x)(OH)2](CO3) x/2·nH2O (═CO3-type) and [Mg(1 − x)Al(x)(OH)2](OH) x ·nH2O (═OH-type), have been investigated in the temperature range of 25–200°C under saturated water vapor pressure (100% RH). Conductivity was measured by the complex impedance method using pressed pellet samples. The conductivity of an OH-type sample (x =0.25) is as high as 4×10−3 Scm−1 already at room temperature. On heating, it increases as slowly (the activation energy E a ∼55meV) as those of liquid electrolyte solutions, suggesting that ions are transported via exchange of protons between OH− and H2O species in the interlayer space of the LDH (a kind of the Grotthus mechanism). The conductivity at 200°C reaches 3×10−2 Scm−1. Although the conductivity of the CO3-type counterpart is considerably low (∼10−6 Scm−1) at room temperature, it increases with increasing temperature with showing a jump by about four orders of magnitude around 80°C, after which the compound is turned into an almost the same liquid-like conductor as the OH-type sample; the conductivity jump is probably due to the interlayer reaction CO3 2− +H2O=2OH− +CO2 (g). Thus those Mg–Al LDH materials show the potential application as solid electrolyte materials for intermediate temperature fuel cells, not only because they have high conductivity but also they should not suffer from the degradation by CO2 which is a serious problem for conventional anion exchange membranes. [Copyright &y& Elsevier]

Abstract: Ionogel electrolytes at medium temperatures were prepared by composite of ionic liquid [1-butyl-3-methylimidazole][bis-(fluoromethanesulfonyl) amide] ([BMIM][TFSI]) with the proton-conducting inorganic solid acid CsHSO4. The incorporation of only 10 wt.% of the ionic liquid into the solid acids drastically increased the conductivity of solid acids over a wide temperature range. The ionogel electrolytes contained up to 40 wt.% of the ionic liquid within their inorganic CsHSO4 networks and had an ion conductivity of 2×10−2 S/cm. [Copyright &y& Elsevier]

Abstract: In this study, we synthesized a molecular hybrid conductor electrolyte using PWA ([H3PW12O40·nH2O]) and [1-butyl-3-methylimidazole][bis-(fluoromethanesulfonyl) amide] ([BMIM][TFSI]) ionic liquid. The [BMIM][TFSI] ionic liquid can interact with the strongly acidic PWA. The hybrids were hydrophilic, and included some water molecules in the structure of the hybrids. The water molecules remained up to 80°C, contributing to improve conductivity under an anhydrous N2 atmosphere. The conductivity of PWA-[BMIM][TFSI] hybrid under anhydrous conditions increased from 10−4 S/cm to 0.04S/cm at 60°C. The conductivity of the hybrids at each temperature was higher than that of pure PWA and [BMIM][TFSI] under anhydrous condition. It can be due to the protonic carriers. [Copyright &y& Elsevier]