Three types of next generation batteries are currently being envisaged among the international community: metal-air batteries, multivalent cation batteries and all-solid-state batteries. These battery designs require high-performance, safe and cost effective electrolytes that are compatible with optimized electrode materials. Solid electrolytes have not yet been extensively employed in commercial batteries as they suffer from poor ionic conduction at acceptable temperatures and insufficient stability with respect to lithium-metal. Here we show a novel type of glasses, which evolve from an antiperovskite structure and that show the highest ionic conductivity ever reported for the Li-ion (25 mS cm À1 at 25 C). These glassy electrolytes for lithium batteries are inexpensive, light, recyclable, non-flammable and non-toxic.Moreover, they present a wide electrochemical window (higher than 8 V) and thermal stability within the application range of temperatures.

The advent of a Li+ or Na+ glass electrolyte with a cation conductivity σi > 10−2 S cm−1 at 25 °C and a motional enthalpy ΔHm = 0.06 eV that is wet by a metallic lithium or sodium anode is used to develop a new strategy for an all-solid-state, rechargeable, metal-plating battery.

A thermodynamic assessment of the Bi-Sn-Zn ternary system was carried out using the CALPHAD approach along with thermodynamic descriptions from new assessments of the Bi-Sn and Bi-Zn systems. Selected experimental data from the literature and our own work were also used. New sets of optimized thermodynamic parameters were obtained that lead to a very good fit between the calculated and experimental data. The Bi-Sn-Zn system is one of the candidates for lead-free solder materials.

The binary Bi-Sn was studied by means of SEM (Scanning Electron Microscopy)/EDS (Energy-Dispersive solid state Spectrometry), DTA (Differential Thermal Analysis)/DSC (Differential Scanning Calorimetry) and RT-XRD (Room Temperature X-Ray Diffraction) in order to clarify discrepancies concerning the Bi reported solubility in (Sn). It was found that (Sn) dissolves approximately 10 wt% of Bi at the eutectic temperature.The experimental effort for the Bi-Zn system was limited to the investigation of the discrepancies concerning the solubility limit of Zn in (Bi) and the solubility of Bi in (Zn). Results indicate that the solubility of both elements in the respective solid solution is approximately 0.3 wt% at 200 • C.Three different features were studied within the Bi-Sn-Zn system. Although there are enough data to establish the liquid miscibility gap occurring in the phase diagram of binary Bi-Zn, no data could be found for the ternary. Samples belonging to the isopleths with w(Bi) ∼ 10% and w(Sn) ∼ 5%, 13% and 19% were measured by DTA/DSC. The aim was to characterize the miscibility gap in the liquid phase. Samples belonging to the isopleths with w(Sn) ∼ 40%, 58%, 77/81% and w(Zn) ∼ 12% were also measured by DTA/DSC to complement the study of Bi-Sn-Zn. Solubilities in the solid terminal solutions were determined by SEM/EDS. Samples were also analyzed by RT-XRD and HT-XRD (High Temperature X-Ray Diffraction) confirming the DTA/DSC results for solid state phase equilibria.

A room-temperature all-solid-state rechargeable battery cell containing a tandem electrolyte consisting of a Li-glass electrolyte in contact with a lithium anode and a plasticizer in contact with a conventional, low cost oxide host cathode was charged to 5 V versus lithium with a charge/discharge cycle life of over 23,000 cycles at a rate of 153 mA·g of active material. A larger positive electrode cell with 329 cycles had a capacity of 585 mAh·g at a cutoff of 2.5 V and a current of 23 mA·g of the active material; the capacity rose with cycle number over the 329 cycles tested during 13 consecutive months. Another cell had a discharge voltage from 4.5 to 3.7 V over 316 cycles at a rate of 46 mA·g of active material. Both the Li-glass electrolyte and the plasticizer contain electric dipoles that respond to the internal electric fields generated during charge by a redistribution of mobile cations in the glass and by extraction of Li from the active cathode host particles. The electric dipoles remain oriented during discharge to retain an internal electric field after a discharge. The plasticizer accommodates to the volume changes in the active cathode particles during charge/discharge cycling and retains during charge the Li extracted from the cathode particles at the plasticizer/cathode-particle interface; return of these Li to the active cathode particles during discharge only involves a displacement back across the plasticizer/cathode interface and transport within the cathode particle. A slow motion at room temperature of the electric dipoles in the Li-glass electrolyte increases with time the electric field across the EDLC of the anode/Li-glass interface to where Li from the glass electrolyte is plated on the anode without being replenished from the cathode, which charges the Li-glass electrolyte negative and consequently the glass side of the Li-glass/plasticizer EDLC. Stripping back the Li to the Li-glass during discharge is enhanced by the negative charge in the Li-glass. Since the Li-glass is not reduced on contact with metallic lithium, no passivating interface layer contributes to a capacity fade; instead, the discharge capacity increases with cycle number as a result of dipole polarization in the Li-glass electrolyte leading to a capacity increase of the Li-glass/plasticizer EDLC. The storage of electric power by both faradaic electrochemical extraction/insertion of Li in the cathode and electrostatic stored energy in the EDLCs provides a safe and fast charge and discharge with a long cycle life and a greater capacity than can be provided by the cathode host extraction/insertion reaction. The cell can be charged to a high voltage versus a lithium anode because of the added charge of the EDLCs.

Glass, unlike a crystalline solid, contains atoms and molecules that do not occupy fixed positions. A glass that contains molecules that attract one another can age with time. We report such a glass that contains A 2 O and (OA) − electric dipoles (A = Li or Na). At a temperature T < 1.2T g ≈ 110 • C (T g is the glass transition temperature) the electric dipoles coalesce with time into clusters within which, unlike in ice, some dipoles condense into ferroelectric, negatively charged molecules locally charge-compensated by weakly attracted A + ions. In an applied electric field, the dipoles are oriented and, over time depending on the T < 110 • C, are aligned parallel to the field axis to yield a solid A + electrolyte with an ionic conductivity σ i > 10 −2 S cm −1 and a huge dielectric constant that makes it suitable for many applications, including safe rechargeable batteries of high energy density and long cycle life. The A-glass electrolytes (A = Li or Na) formed from A 2.99 Ba 0.005 ClO + xH 2 O (x < 1) exhibit an unusually high dielectric constant as well as an alkali-ion conductivity σ i > 10 −2 S cm −1 at 25• C after the glass has been conditioned. 1 The solvated water leaves the glass as HCl during heating to 250• C; and most, if not all, of the residual OH − are evaporated as H 2 O above 230Measurement of the inverse loss tangent, tan −1 δ = ε /ε , as a function of frequency at different temperatures showed two resonant frequencies that were coupled to one another. We interpret these resonances to be due to rotational vibrations of the A 2 O and OA − electric dipoles. The vibrations were coupled in the temperature interval 70 < T < 90• C at a frequency 10 < f < 500 Hz, and a chronopotentiometric measurement of the dc current in a symmetric Li/Ca doped Li-glass/Li cell at 44• C 1,2 showed an increase with time of the lithium conductivity in the as-prepared Li-glass. The as-prepared glasses were furnace cooled, not quenched, to 25• C. In this paper we investigate the frequency and temperature dependences of the dielectric constant and how the activation enthalpy H m for a Na + hop in an Au/Na-glass/Au cell is conditioned by an orientation of electric dipoles. We show that a designed thermal history under an applied ac electric field can provide a rapid increase of dc cation conductivity to a σ i > 10 −2 S cm −1 and decrease of an activation energy of mobility to H m = 0.06 eV at 25• C. Materials and MethodsSynthesis.-Nominal glass/amorphous solid electrolytes Na 2.99 Ba 0.005 O 1+x Cl 1-2x were processed in a wet synthesis as described previously 1 from the commercial precursors NaCl (99.9%, Merck), Na(OH) (>99%, Merck), and Ba(OH) 2 · 8H 2 O (98.5%, Merck). The glass products were dried by HCl evaporation at lower temperatures and the loss of the OH − by the reaction 2OH − = O 2− + H 2 O↑ above 230• C as previously shown in Ref. 1; the reaction leaves a glass/amorphous solid containing electric dipoles. Samples "as prepared" were slowly cooled down to room temperature. Some samples were subject to heating ...

In this work, we investigated the systems of (Li, Ca)-O-(Cl, Br) under high pressure and temperature for the synthesis of lithium-rich anti-perovskite (LiRAP) halides. We successfully synthesized Li 3-x Ca x/2 OCl anti-perovskite with x = 0.0, 0.1, 0.2 near 0.5 GPa and temperatures of 400-425 K and Li 3 OBr anti-perovskite at 3.0 GPa and 450 K. Different from the synthetic route previously reported at ambient pressure, LiA + 2LiOH → Li 3 OA + H 2 O, the LiRAP halides under high P-T conditions are formed by dehydration of endmember and Ca-doped halide hydrates with a general formula of Li 2x+1 A(OH) 2y , where A can be Cl or Br and x must be equal to y. This proposed formula predicts several new halide hydrates including Li 3 Cl(OH) 2 , Li 5 Cl(OH) 4 , Li 3 Br(OH) 2 , and Li 5 Br(OH) 4 , indicating that halide hydrates are structurally flexible to accommodate a range of lithium and hydroxide occupancies in the puckered layers of [Li 2x+1 (OH) 2y

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