Glass-ceramic Solid Electrolyte Research Articles

Effects of Cr2O3 doping on crystallization behavior and electrochemical properties of Li2O–Al2O3–TiO2–P2O5–SiO2 glass-ceramics

Bulk glass-ceramic solid electrolytes of the Li2O–Al2O3–TiO2–P2O5–SiO2 system were prepared by melt-quenching and one-step heat treatment method in this work. The effects of the gradual substitution of Al3+ by Cr3+ and the elevation of the heat treatment temperature on the phase composition, microstructure, and ionic conductivity of the solid electrolytes were systematically investigated. The results show that the major crystalline phase is LiTi2(PO4)3, and the conductivity of the glass-ceramics initially enhances and then decreases as the Cr2O3 content increases from 0 mol% to 3 mol%. The highest conductivity is obtained when the Cr2O3 content is 2 mol%, measuring 4.45 × 10−4 S/cm at 25 °C. Additionally, the mechanism of the surface exfoliation of the glass-ceramics and the enhancement achieved by doping with Cr3+ are explained according to microstructure analysis. This work provides a simple method to enhance the electrical conductivity and physical properties of LATP glass-ceramic solid electrolytes, which is of great significance for the design of lithium-ion solid electrolytes.

Synthesis of Sb-doped Li10P3S12I solid electrolyte and their electrochemical performance in solid-state batteries

The glass-ceramic Li10P3S12I solid electrolyte exhibited moderate ionic conductivity of ∼3 mS cm−1, but it shows low interface stability with lithium, poor moisture stability, and the electrochemical performance is not well established with respect to lithium. In this work, we enhance the ionic conductivity, interface stability, and air stability using Sb-substitution in Li10P3S12I glass-ceramic solid electrolyte using a high-energy ball milling process followed by a low heat treatment process. The ionic conductivity analysis reveals that the prepared Li10.1P2.95Sb0.05S12I glass ceramic composition shows a higher ionic conductivity of 5.9 mS cm−1 at 25 °C than Li10.1P2.95Sb0.05S12I (5.06 mS cm−1). The Li10.1P2.95Sb0.05S12I glass ceramic symmetric cell exhibits a better critical current density of 1 mA cm−2 than bare (0.7 mA cm−2). Also, it demonstrates better DC cyclability at 0.25 mA cm−2 without internal short circuits after 80 cycles. The Sb-substitution not only enhanced the ionic conductivity, also increased the moisture stability according to HSAB theory. The lithium solid-state battery is constructed using the Li10.1P2.95Sb0.05S12I electrolyte that demonstrates a high discharge capacity of 146 mAh g−1 at 0.1C rate than bare electrolyte (126 mAh g−1).

Scaling up picosecond laser ablation of a LATGP-type glass-ceramic solid electrolyte for all-solid-state battery production

All-solid-state batteries are an intensively studied technology expected to complement conventional lithium-ion batteries in the near future. Research into fundamental production processes is crucial for enabling economic, industrial-scale all-solid-state battery production. Laser radiation is a production tool suited for contour cutting and surface structuring of inorganic solid electrolyte separators. In the scope of this work, the laser ablation of the commercial glass-ceramic solid electrolyte lithium aluminum germanium titanium phosphate (LAGTP) using ultrashort-pulsed laser radiation at different wavelengths, fluences, and pulse repetition rates is studied. Ablation thresholds, efficiencies, and rates were determined by manufacturing percussion drillings, trenches, and cavities. Geometry dependencies, such as the ablation rate decay with advancing depth during laser cutting, necessitated an application-oriented determination of ablation metrics. The surface qualities of the solid electrolyte layers were evaluated after laser ablation by scanning electron microscopy and surface roughness measurements. A wavelength of 532 nm was found to be beneficial compared to shorter and longer wavelengths in terms of productivity and ablation quality, reaching volume ablation efficiencies up to 36 μm3∙μJ−1 and surface roughnesses Sa below 500 nm. The determined metrics are discussed for ablation cutting and structuring of solid electrolyte layers in all-solid-state battery production, considering throughput and surface quality. The results provide insight into the ablation behavior of glass-ceramic materials and support the application of ultrashort-pulsed laser ablation in next-generation battery production.

Realizing high-capacity all-solid-state lithium-sulfur batteries using a low-density inorganic solid-state electrolyte

Lithium-sulfur all-solid-state batteries using inorganic solid-state electrolytes are considered promising electrochemical energy storage technologies. However, developing positive electrodes with high sulfur content, adequate sulfur utilization, and high mass loading is challenging. Here, to address these concerns, we propose using a liquid-phase-synthesized Li3PS4-2LiBH4 glass-ceramic solid electrolyte with a low density (1.491 g cm−3), small primary particle size (~500 nm) and bulk ionic conductivity of 6.0 mS cm−1 at 25 °C for fabricating lithium-sulfur all-solid-state batteries. When tested in a Swagelok cell configuration with a Li-In negative electrode and a 60 wt% S positive electrode applying an average stack pressure of ~55 MPa, the all-solid-state battery delivered a high discharge capacity of about 1144.6 mAh g−1 at 167.5 mA g−1 and 60 °C. We further demonstrate that the use of the low-density solid electrolyte increases the electrolyte volume ratio in the cathode, reduces inactive bulky sulfur, and improves the content uniformity of the sulfur-based positive electrode, thus providing sufficient ion conduction pathways for battery performance improvement.

Fast ion conduction and stable [Na-Si-P] glass-ceramic solid electrolyte mixed with hafnium and scandium ions: Application to Na-ion full cell

NASICON type glass and glass-ceramic electrolyte materials have become very attractive choices recently to integrate into any Na+ ion storage system. This investigates glass and glass-ceramic electrolytes using the formula: 45(Na2O + NaF)-10SiO2-35P2O5-(10-x)HfO2-xSc2O3 (labeled as [NSP]90(10-x)HfScx; x = 0, 2, 4, 6, 8, 10 mol%) via the high energy mechanical milling followed by heat treating for different schedules. The thermal stability parameter (ΔT = Tc-Tg) and bulk conductivity are obtained to be highest for [NSP]90(10-x)HfScx glass electrolyte before and after heat treatment. XRD results revealed of Glass-ceramic powder that NASICON type Na3Sc2(PO4)3 and triclinic Na2HfSi2O7 major crystalline phases, which are reported to be highly conductive and stable. [NSP]90Hf4Sc6 −12 h glass-ceramic electrolyte stabilizes more against Na- metal than its corresponding [NSP]90 (10-x)HfScx glass electrolyte. The lowest interfacial resistance of [NSP]90Hf4Sc6 −12 h is observed than its pristine ell, directly ascribes the compatibility of Na metal-[NSP]90Hf4Sc6-12 h/Na electrolyte combination. The irreversible capacity and stability of full cell NVMP/[NSP]90Hf4Sc6/NVZn is also explored in light of the oxidation and redox reaction behavior.

Low temperature ensures FeS2 cathode a superior cycling stability in Li7P3S11-based all-solid-state lithium batteries

All-solid-state lithium sulfide batteries exhibit great potential as next-generation energy storage devices due to their low cost and high energy density. However, the poor conductivity of the solid electrolytes and the low electronic conductivity of sulfur limit their development. In this work, the highly conductive Li7P3S11 glass-ceramic solid electrolyte with room temperature conductivity of 1.27 mS cm−1 is synthesized and combined with the FeS2 cathode and Li-In anode to fabricate FeS2/Li7P3S11/Li-In all-solid-state Li-S battery. The assembled battery delivers high initial discharge capacities of 620.8, 866.4 mAh g−1, and 364.8 mAh g−1 at 0.1C under room temperature, 60°C and 0°C, respectively. It shows a discharge capacity of 284.8 mAh g−1 with a capacity retention of 52.4% after 80 cycles at room temperature. When the operating temperature rises to 60°C, this battery suffers a fast decay of capacity in 40 cycles. However, this battery sustains a high discharge capacity of 256.6 mAh g−1 with a capacity retention of 87.9% after 100 cycles under 0°C, smaller volume expansion of ASSBs at 0°C keep the solid/solid contact between the electrolyte particles, thus resulting in better electrochemical performances. EIS and in situ pressure characterizations further verify that the differences of electrochemical performances are associated with the volume variations caused by the temperature effects. This work provides a guideline for designing all-solid-state Li-S which is workable in a wide temperature range.

Delithiation dynamics of the LICGC electrolyte out of the voltage limits

The recently developed concept of an all-solid-state Li battery is deemed by many as a breakthrough toward safer and higher-capacity rechargeable devices. This, in turn, motivates the researchers in pushing all the battery components up to and beyond operational limits to test the materials’ performance. Herein we present an in-situ characterization of the response of the Lithium Conductive Glass-Ceramic (LICGC) solid electrolyte to the application of a cycling voltage, extending the operating limits up to ±15 V. The purpose was to clarify the dynamics of the delithiation process out of the standard conditions. The Atomic Force Microscopy (AFM) has been employed to monitor the evolution of the LICGC surface morphology induced by high voltage. The in-situ measurement showed that the delithiation of LICGC (encompassed with thin metallic current collectors) leads to the out-diffusion of Li through defects in the current collectors, and the formation of the Li-based nanoparticles (NPs) on the sample surface. The growth of NPs and the formation of nano-to-macro clusters is dependent on the applied voltage: the higher the voltage the larger the NPs. The AFM results are supported by the Neutron Depth Profiling data, which confirm high concentrations of Li in NPs, and by X-rays photoelectron spectroscopy, which clarifies the composition of NPs.

Development of high ionic-conductive Li1.5Al0.5Ge1.5(PO4)3 glass-ceramic solid electrolyte sheet at low temperature using glass/powder composite

Development of high ionic-conductive Li1.5Al0.5Ge1.5(PO4)3 glass-ceramic solid electrolyte sheet at low temperature using glass/powder composite

Influence of R=Y, Gd, Sm on Crystallization and Sodium Ion Conductivity of Na5RSi4O12 Phase.

New sodium-based battery concepts require solid electrolytes as ion conducting separators. Besides NaSICON and β-Al2O3 in the Na2O-R2O3-SiO2 system (R = rare earth), a rarely noticed glass-ceramic solid electrolyte with the composition Na5RSi4O12 (N5-type) exists. The present study addresses the investigation of the ionic conductivity of Na5RSi4O12 solid electrolytes sintered from pre-crystallized glass-ceramic powders. The sintering behavior (optical dilatometry), the microstructure (SEM/EDX), and phase composition (XRD), as well as electrochemical properties (impedance spectroscopy), were investigated. To evaluate the effect of the ionic radii, Y, Sm and Gd rare elements were chosen. All compositions were successfully synthesized to fully densified compacts having the corresponding conducting N5-type phase as the main component. The densification behavior was in agreement with the melting point, which decreased with increasing ionic radii and specific cell volume. Alternatively, the ionic conductivities of N5-phases decreased from Y to Gd and Sm containing samples. The highest ionic conductivity of 1.82 × 10−3 S cm−1 at 20 °C was obtained for Na5YSi4O12 composition. The impact of grain boundaries and bulk conductivity on measured values is discussed. A powder-based synthesis method of this glass-ceramic solid electrolyte using different rare earth elements opens possibilities for optimizing ionic conductivity and scalable technological processing by tape casting.

Stabilizing Interface between Li2S-P2S5 Glass-Ceramic Electrolyte and Ether Electrolyte by Tuning Solvation Reaction.

Using solid-liquid hybrid electrolytes is an effective strategy to overcome the large solid/solid interfacial resistance in all-solid-state batteries and the safety problems in liquid batteries. The properties of the solid/liquid electrolyte interphase layer (SLEI) are essential for the performance of solid-liquid hybrid electrolytes. In this work, the solvation reactions between Li2S-P2S5 glass-ceramic solid electrolytes (SEs) and ether electrolytes were studied, and their influence on the SLEI was examined. Although 1,2-dimethoxyethane (DME) reacted with the Li2S-P2S5 glass-ceramic SE to form a dense SLEI, 1,3-dioxolane (DOL) severely corroded the SE, resulting in a loose SLEI. Consequently, a stable SLEI formed with DME. Using a combination of the Li2S-P2S5 glass-ceramic SE and the DME-based liquid electrolyte (LE), stable lithium plating/stripping cycles over 1000 h and a hybrid Li-S battery that retained a specific capacity of 730 mAh g-1 after 200 cycles were demonstrated. The knowledge of the reactions between the sulfide electrolytes and the organic LEs is instructive for the design of stable sulfide-liquid hybrid electrolytes for advanced batteries.

Preparation, Microstructure and Electrical Conductivity of LATP/LB Glass Ceramic Solid Electrolytes

The Li2O-Al2O3-TiO2-P2O5 system glass ceramic solid electrolytes were prepared by adding Li3BO3 (LB) frits. The phase composition, microstructure and electrical properties of glass ceramics were investigated by using X-ray diffraction, scanning electron microscopy and AC impedance spectroscopy. The results show that the principal crystalline phase of all glass ceramic samples was LiTi2(PO4)3. The grain sizes of glass ceramic sample increase with the increase of sintering temperature. When the additive amount of LB is 1wt %, the glass ceramic solid electrolyte sintered at 950 oC shows the highest room-temperature ionic conductivity of 1.9×10−4 S.cm−1, which can be expected to be used in solid-state lithium-ion batteries.

Sintering of sodium conducting glass ceramics in the Na2O-Y2O3-SiO2-system

A solid electrolyte is a core component for the development of low temperature sodium batteries with metallic Na-anode. The Na5YSi4O12 (N5) composition in the Na2O-Y2O3-SiO2 system shows a high ionic conductivity comparable to NASICON or β-Al2O3. Up to date glass ceramic solid electrolytes of this type have been mainly prepared by crystallization of monolithic, molten glass components. We show that this material can be processed via the glass-ceramic powder route starting with a glass powder. A glass with a composition according to the stoichiometry of the Na5YSi4O12-phase and tailored by addition of P2O5 allows the separation of sintering and crystallization of the glass powder resulting in dense microstructure. Thermophysical properties and phase content have been correlated with ionic conductivity. The densification and crystallization are completed at temperatures below 1100 °C. Grain conductivities up to 0,18 mS cm−1 at room temperature in sintered glass ceramic microstructures are demonstrated.

Optimization of lithium ion conductivity of Li2S-P2S5 glass ceramics by microstructural control of crystallization kinetics

To improve the Li ion conductivity in a glass-ceramic solid electrolyte, the microstructural control for Li2S-P2S5 glass ceramics was investigated based on crystallization kinetics. 75Li2S∙25P2S5 (mol.%) glass was synthesized by a ball-milling method, and glass-ceramics were prepared by crystallization with heat treatment at various temperatures with appropriate holding times. Crystallization kinetics—nucleation rate, I, and crystal growth rate, U, of 75Li2S∙25P2S5 glass—were determined by differential thermal analysis and in situ transmission electron microscopy (TEM). The obtained parameters were referred to optimize the heat treatment conditions. Through the optimization, Li ion conductivity was improved by 80% in comparison with the glass electrolyte, in which a conductivity of 1.33 × 10−3 S cm−1 was achieved at room temperature by controlling the microstructure and the formation of a network structure in the glass matrix. This approach brings out the best performance of 75Li2S∙25P2S5 glass-ceramics. The effective medium theory was adopted to discuss the formation of a fast ion-conducting network for the improvement of Li ion conductivity. The present method can provide an effective preparation route of a glass-ceramic solid electrolyte for all-solid Li-ion batteries.

Single-step ball milling synthesis of highly Li+ conductive Li5.3PS4.3ClBr0.7 glass ceramic electrolyte enables low-impedance all-solid-state batteries

Single-step ball milling synthesis of a highly conductive glass ceramic solid electrolyte enables a low-impedance all-solid-state battery.

The Preparation of Li1.5Al0.5Ge1.5(PO4)3 Glass-Ceramics with Lithium-Ion Conductivity from an Oxalate Precursor

An Li1.5Al0.5Ge1.5(PO4)3 glass-ceramic solid electrolyte having a NASICON structure and possessing lithium-ion conductivity is prepared. The differential scanning calorimetry data show that the oxalate precursor significantly reduces the melting temperature of a raw material by 200–300°C to synthesize the Li1.5Al0.5Ge1.5(PO4)3 glass ceramics. The glass appears to be transparent and colorless after melting at 1150°C and subsequent cooling. The glass transition temperature is 512°C, whereas an intense exothermic crystallization peak of Li1.5Al0.5Ge1.5(PO4)3 is observed at 633°C. The monophase glass-ceramics, free of nonconductive impurities, is obtained via glass crystallization at 850–900°C. The ionic conductivity of the Li1.5Al0.5Ge1.5(PO4)3 glass-ceramics is 2 × 10–4 S/cm at room temperature.

Quasi-solid sodium ions electrolyte of $${\hbox {Na}}_{2} \hbox {O}{-} {\hbox {B}}_{2} {\hbox {O}}_{3}{-} {\hbox {SiO}}_{2} {-} {\hbox {H}}_{2} \hbox {O}$$ system hydrated glass

$${\hbox {Na}}_{2}\hbox {O} {-} {\hbox {B}}_{2} {\hbox {O}}_{3}{-} {\hbox {SiO}}_{2}{-} {\hbox {H}}_{2} {\hbox {O}}$$ system hydrated glass with $$T_{\mathrm {g}}$$ ranges from $$-10 \hbox { to } 150^{\circ }$$ C is synthesized by aqueous chemical methods and is applied to symmetrical cells as quasi-solid electrolyte. At the temperature around $$T_{\mathrm {g}}$$ , the solid state transforms to quasi-solid state, whose mechanical property keeps like gel electrolyte, but the conductivity leaps from $$5.31 \times 10^{-6} \, {\hbox {S cm}}^{-1}$$ to $$5.43 \times 10^{-3} \, {\hbox {S cm}}^{-1}$$ , much higher than most of the glass–ceramic electrolytes. As most of the solvated water is evaporated, $${\hbox {H}}_{2}{\hbox {O}}$$ left in the system distributes in the intervals as hydroxyl, which is much benefit to the ions transportation, and more important is to increase the voltage window to 2.24 V and even higher. The cycle performance is also researched. After 1000 circulations, there is still 65% capacity retention and no obvious damage is discovered in the electrolyte, which means much better cycle property of the electrolyte than gel electrolyte. Other compositions in the quasi-solid system including different contents of $${\hbox {B}}_{2}{\hbox {O}}_{3}$$ , $${\hbox {Na}}_{2} {\hbox {SO}}_{4}$$ and m in sodium silicate $${\hbox {NaO}}_{2}{\cdot }{\hbox {mSiO}}_{2}$$ are also studied. In general, quasi-solid $${\hbox {Na}}_{2}\hbox {O} {-} {\hbox {B}}_{2}{\hbox {O}}_{3}{-} {\hbox {SiO}}_{2}{-} {\hbox {H}}_{2}{\hbox {O}}$$ system owns better conductivity and cycle performance than most glass–ceramic solid electrolyte, and it is environment-friendly, inexpensive and practical to be used as sodium ions quasi-solid electrolyte.

Synthesis and characterizations of highly conductive and stable electrolyte Li10P3S12I

A novel glass-ceramic solid electrolyte Li10P3S12I is synthesized, which delivers a high ionic conductivity of 6.4 mS/cm at 25 °C and a low activation energy of 0.26 eV. Li10P3S12I also exhibits significantly enhanced stability and low interfacial resistance against Li metal compared with thiophosphates. Tracer-exchange Li NMR reveals that lithium ions transport preferably through the glass phase and glass-ceramic interface in Li10P3S12I. Careful control of the synthesis process to avoid complete crystallization helps stabilize the highly Li-conductive phase.

Freestanding all-solid-state rechargeable lithium batteries with in-situ formed positive electrodes

Abstracts Freestanding all-solid-state rechargeable lithium batteries (Li/LiPON/LATP sheet/Au, SSB) operating at 2.3 V were developed. The electrochemical insertion of lithium into a white-colored Li+ conductive glass-ceramic solid electrolyte (LATP) sheet transformed the electrolyte into a blue-colored in-situ formed electrode, which provided a low-resistance electrode/solid electrolyte interface of ca. 100 Ω cm2. In addition, the interfacial resistances at both Li/LiPON and LiPON/LATP were less than 100 Ω cm2, and all the components in the SSB were combined with low-resistance interfaces. As a consequence, the resultant SSB delivered a clear redox peak at 100 mV s−1 in the cyclic voltammetry measurements at 25 °C. The reaction region of the in-situ formed electrode was limited around the Au/LATP interface at 25 °C, but this region expanded into the LATP sheet at higher temperatures. At 100 °C, the resultant SSB delivered ca. 300 μΑh cm−2 and a volumetric energy density of 53 Wh L−1. The electronic conductivity of the in-situ formed electrode appeared to control the reaction region, and thus a SSB using a carbon-LATP composite sheet delivered a larger discharge capacity at 25 °C than that of the SSB using only LATP operated at 100 °C. The use of conductive LATP sheets may be a possible solution for developing SSBs that can be rationally designed according to the operational environments of the IoTs.

Amorphous versus Crystalline Li3PS4: Local Structural Changes during Synthesis and Li Ion Mobility

Glass–ceramic solid electrolytes have been reported to exhibit high ionic conductivities. Their synthesis can be performed by crystallization of mechanically milled Li2S–P2S5 glasses. Herein, the a...

Outstanding cycle stability and rate capabilities of the all-solid-state Li–S battery with a Li7P3S11 glass-ceramic electrolyte and a core–shell S@BP2000 nanocomposite

A Li7P3S11 glass-ceramic solid electrolyte and a core–shell S@BP2000 nanocomposite are used to fabricate all-solidstate Li–S batteries, which exhibit outstanding cycle stability and rate capabilities.