High Conductivity Solid Electrolyte Research Articles

Ta-Doped Li7La3Zr2O12 for Water-Stable Lithium Electrode of Lithium-Air Batteries

Garnet-type high lithium ion conductivity solid electrolytes with nominal compositions of Li7-xLa3Zr2-xTaxO12 (x = 0–0.7) were prepared by using a sol-gel precursor and are proposed as the protective layer for a water-stable lithium electrode for lithium-air rechargeable batteries. The Li6.75La3Zr1.75Ta0.25O12 (LLZ-0.25Ta) composition sintered at 1,180°C for 36 h showed the highest relative density of 96.7% and resistance to water permeation. The LLZ-0.25Ta was stable in contacting with lithium metal and also in a saturated LiOH/10 M LiCl aqueous solution. The total and bulk conductivities of the sintered LLZ-0.25Ta pellet were 5.20 × 10−4 and 6.55 × 10−4 S cm−1 at 25°C, respectively. The Li/LLZ-0.25Ta/Li cell showed a stable cell resistance of 310 Ω cm2 at 25°C for 4 months. However, polarization experiments on the Li/LLZ-0.25Ta/Li cell suggest a lithium dendrite short-circuit after 100 s at 0.5 mA cm−2 and after 2000 s of polarization at 0.1 mA cm−2 at room temperature.

Solution-Based Synthesis and Characterization of Lithium-Ion Conducting Phosphate Ceramics for Lithium Metal Batteries

High conductivity solid electrolytes are promising solutions for extremely high energy density battery systems including Li/air and Li/sulfur. Lithium aluminum titanium phosphate (LATP) ceramics have among the highest reported ionic conductivities and are promising candidates as solid electrolytes. Li1.3Al0.3Ti1.7(PO4)3 powders were synthesized for the first time via a solution-based method at synthesis temperatures as low as 650 °C. The ceramic powders are characterized using X-ray powder diffraction, solid state magic angle spinning (MAS) nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The effect of Li and Al local structure and the presence of amorphous and crystalline impurities on electrolyte morphology and sinterability have been studied in detail.

High Conductivity Solid Oxide Electrolyte Composite-Laminates Utilizing Scandia/Ceria Co-Doped Zirconia Core with Yttria Stabilized Zirconia Outer Skins

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Organic ionic plastic crystals: recent advances

Investigations into the synthesis and utilisation of organic ionic plastic crystals have made significant progress in recent years, driven by a continued need for high conductivity solid state electrolytes for a range of electrochemical devices. There are a number of different aspects to research in this area; fundamental studies, utilising a wide range of analytical techniques, of both pure and doped plastic crystals, and the development of plastic crystal-based materials as electrolytes in, for example, lithium ion batteries. Progress in these areas is highlighted and the development of new organic ionic plastic crystals, including a new class of proton conductors, is discussed.

Potassium-conductive solid electrolytes in systems K2 − 2x M2 − x V x O4(M = Al, Fe)

New high-conductivity solid electrolytes based on potassium monoaluminate and monoferrite are synthesized by partial substitution of V5+ for three-charged cations. In both systems, the introduction of vanadium cations leads to a substantial increase in the conductivity, with the maximum values corresponding to upper boundaries of the monophase solid solution regions. The principal factors responsible for the high conductivity are the formation of potassium vacancies at the substitutions M3+ → V5+ + 2V’K and the extension of the temperature range of existence of high-temperature modifications of KAl(Fe)O2.

Preparation of High Lithium Ion Conductive Glass-Ceramics Solid Electrolytes in the LiTi<sub>2</sub>(PO<sub>4</sub>)<sub>3</sub> System by the Mechanochemical Method and their Application as Coating Materials of LiCoO<sub>2</sub>

Amorphous fine powder in the Li2O-Al2O3-TiO2-P2O5 (LATP) system were prepared directly from a mixture of Li2O, Al2O3, TiO2, and P2O5 as starting materials using a mechanical milling technique at room temperature. LATP glass-ceramics were obtained by heat treatment of the mechanochemically prepared amorphous powder over the crystallization temperature. X-ray diffraction peaks due to LiTi2(PO4)3 and AlPO4 crystals for LATP glass-ceramics were observed. Thus, high lithium ion conducting LATP glass-ceramics solid electrolytes were prepared successfully from the mechanochemically prepared amorphous powder. The LATP glass-ceramic fine particles were investigated as coating materials of LiCoO2 cathode in lithium ion batteries. The LATP glass-ceramics coated LiCoO2 electrode materials exhibited a good charge-discharge performance for charging up to a high voltage (4.5 V vs. Li/Li+).

High Ion Conductive Solid Polymer Electrolytes Based on the Organic-Inorganic Hybrid Matrix

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Toward Commercialization of the Beta-Alumina Family of Ionic Conductors

The beta-alumina family of materials has played a central role in the field of solid-state ionics. β- and β-alumina have been a principal theme in the field ever since Yao and Kummer reported the extraordinarily high conductivity for sodium β-alumina. The material “came of age” at a time when there was great interest in the science and technology of highconductivity solid electrolytes. A previous MRS Bulletin review introduced this broad family of materials, examining the range of compositions and the two major structures. The beta-alumina family emerged as almost an ideal system in which to explore structure-property relations, as its unusual structure is responsible for its remarkable ion-transport properties. Although the initial interest in this material, and the one which endures to this day, is its rapid sodium-ion transport, the rich ion-exchange chemistry added a dimension to this material that few inorganic systems can match, let alone exceed. β-alumina, in particular, is an almost universal solid electrolyte for cations. It constitutes a broad family of solid electrolytes whose properties are dependent upon the nature of the ion inserted into the conduction plane. As a result, the β-aluminas have served as model systems for a wide range of studies: proton transport and mixed-ion diffusion, order-disorder reactions, and superlattice phenomena. Moreover, these β-alumina compositions demonstrated that fast-ion transport was not limited to a few monovalentions, but could be extended to divalent and even trivalent cations. With the latter materials, the interest was not necessarily ion transport, but optical properties instead. The presence of trivalent cations in this unusual structure, coupled with the ability to control the chemistry of the local environment, enabled the β-aluminas to exhibit a number of novel optical properties.

Lithium ion migration pathways in LiTi2(PO4)3 and related materials

The diffusion pathways of Li+ ions within the frameworks of the high conductive solid electrolytes LiTi2(PO4)3 and the Al-doped one Li1.3Ti1.7Al0.3P3O12 are determined by molecular mechanics and molecular dynamics methods. From a potential energy profile for the lithium migration in LiTi2(PO4)3, the barrier height of lithium migration is estimated as 28.95 kJ/mol (0.30 eV) which is in excellent agreement with experimental data. The main influence on the activation energy of lithium diffusion is caused by changes in electrostatic interactions. Long molecular dynamics simulations for Li1.3Ti1.7Al0.3P3O12 also confirm a solid state diffusion process via rare and sporadic hopping of Li+ ions from their energy minimum site to a neighboring energy minimum site.

Investigations on a High-conductivity Solid Electrolyte System, Bi2O3–Y2O3

Investigations on a High-conductivity Solid Electrolyte System, Bi2O3–Y2O3

Electron beam writing in thin films of highly conducting solid electrolytes RbAg4I5and CsAg4Br3−xI2+x

Abstract The structures of thin films of RbAg4I5 and CsAg4Br3-x I2+x, vacuum deposited on thin carbon supports, were investigated in a scanning transmission electron microscope. It has been found that a phase with a high ionic conductivity (solid electrolyte) formed in annealed films is very sensitive to electron irradiation. The use of a focused electron beam is demonstrated to produce directly features in films of the solid electrolytes.

High conductivity solid electrolytes in the crystalline state at room temperature

By “high conductivity solid electrolytes”, the present author refers to the electrolytes exhibiting ionic conductivities higher than 10 −3 S cm −1 in the solid state. As high conductivity solid electrolytes in the crystalline state at room temperature, we have some univalent ion conductors such as H +, Li +, Na +, Ag +, Cu + and F − conductors. In this paper, some of their characteristics are described briefly.

ChemInform Abstract: Structure and Properties of Sn(II)‐β′′‐Alumina.

AbstractSingle crystals of Sn(II)‐β''‐alumina are prepared by ion‐exchange of Na‐β''‐alumina using molten anhydrous SnCl2 (400 °C, inert atmosphere, 20 min).

Frontiers in β″-Alumina Research

Beta and β″-alumina are remarkable solid electrolytes whose study has been a principal theme in the field of solid state ionics ever since Yao and Kummer first reported the exceptionally high conductivity of sodium β-alumina in 1967. The unusual properties of sodium β-alumina stimulated widespread interest in both the science and technology of high conductivity solid electrolytes. Since Yao and Kummer's seminal work, many solid electrolytes have been explored, but interest in the β and β″-aluminas has endured, principally because of their virtually unique ability to undergo ion exchange in which the sodium ions are replaced by a wide variety of monovalent, divalent, and trivalent cations as well as various protonic species. The β and β″-aluminas thus are not single compounds, but a family of solid electrolytes with diverse properties and potential technological applications.Kummer first pointed out the ion exchange properties of sodium β-alumina by showing that the sodium ions in the structure can be replaced by different monovalent cations, such as Li+, K+, as well as H(H2O)x+ and NH4+. More recent studies have shown that the ion exchange chemistry of sodium β″-alumina, is far richer than that of sodium β″-alumina. In fact, the sodium ion content of β″-alumina can be exchanged for virtually any +1, +2, or +3 cation in the periodic chart.

Recent developments in β″ alumina

The multivalent β″-aluminas are the first family of high conductivity solid electrolytes for divalent and trivalent cations. The rich ion exchange chemistry of these materials leads to a variety of chemical environments within the conduction plane which consequently influence their ion transport and optical properties. This paper reviews some of the pertinent structural aspects of the multivalent β-aluminas and considers the properties of selected systems which contain either mixed ions or ions with two valence states within the conduction plane. The results indicate that the multivalent exchanged β-aluminas are excellent materials for studying the effects of ion/lattice and ion/ion interactions in 2-dimensional systems.

Ionically high conductive solid electrolytes composed of graft copolymer-lithium salt hybrids

Preparation a partir de poly [methacryloyl oligo (oxyde d'ethylene)] et de LiOCl 4 ou LiPF 6

Performance of Ag/RbAg4I5/I2 solid electrolyte batteries after ten years storage

Solid state batteries were designed around the high conductivity solid electrolyte material RbAg4I5, with the polyiodide salts of tetramethylammnium iodide (Me4NI5 and Me4NI9) as cathodes and silver as the anode. Three-volt batteries, comprising five cells were designed into a hermetic package and fabricated for evaluaton. In March of 1983 these batteries completed 10 years of sto rage at temperatures of -15°C and 23°C. Some disproportionation of the solid electrolyte occurred during the low temperature storage with an increase in the resistance of about two orders of magnitude. This resistive degradation of the batteries was found to be reversible.

Divalent beta″-aluminas: High conductivity solid electrolytes for divalent cations

The Na + content of beta″-alumina can be replaced by a variety of divalent cations in simple ion exchange reactions. The resulting divalent beta″-aluminas are the first family of high conductivity solid electrolytes for divalent cations. Divalent beta″-aluminas which have been prepared so far include conductors of Ca 2+, Sr 2+, Ba 2+, Zn 2+, Cd 2+, Pb 2+, Hg 2+, and Mn 2+. Most have conductivities of about 10 -6 (Ω cm) -1 at 40°C and 10 -1 (Ω cm) -1 at 300–400°C. However, the conductivity of Pb 2+ beta″ alumina is 4.6x10 -3 (Ω cm) -1 at 40°C, nearly equal to that of Na + beta″-alumina. Preliminary structures studies indicate that order-disorder reactions among the divalent cations and vacancies in the conduction region of beta″-alumina critically influence conductivity in the structure.

Preparation and characterization of the solid electrolyte system RbCu4i2− xCl3+ x (−0.25⩽ x⩽0.75)

The quaternary system RbCu 4I 2− x Cl 3+ x (−0.25⩽0.75) which includes the high copper ion conductivity solid electrolyte Rb 4Cu 16I 7Cl 13 has been studied by means of X-ray diffraction, photoacoustic spectroscopy, X-ray photoelectron spectroscopy, and electrical conductivity measurements. Samples were prepared starting with purified CuCl, CuI, and RbI. It was found that the lattice constant of the solid electrolyte varies from 10.011 to 10.019 Å (±0.002 Å) within the range 0.125< x<0.25. This fact indicates the existence of a solid solution in a narrow compositional range.

New solid electrolytes for sensor applications

Beta and beta″ alumina remain the most versatile solid electrolytes for cations. They are the only solid electrolytes, with the exception of the closely-related beta and beta″ gallates, which conduct a variety of ions. In general, most ions are more conductive in beta″ alumina than in beta alumina. With the protonic and divalent forms, the differences are dramatic. The protonic beta″ aluminas are high-conductivity solid electrolytes for various protonic species. They are unusually stable and might possibly find applications in sensors functioning in the range of about 0 to 300 °C. The divalent beta″ aluminas have no precedent. Their use in sensors may be restricted by problems of ion specificity. But, since no comparable compounds exist, they may lead to devices which were previously impossible for want of suitable materials.