Transparent flexible glassy inorganic solid electrolytes and methods of making the same

Abstract

The present invention provides a transparent flexible glassy inorganic solid electrolyte having the following chemical formula: NaAlO a Cl 4‑2a -X x ; wherein X is selected from one or more of SeO2, TeO2, and GeO2; 0.4≤a≤0.8, 0.01≤x≤0.1. The present invention also provides a method of making the transparent flexible glassy inorganic solid electrolyte of the present invention. The solid electrolyte of the present invention is transparent and flexible at room temperature, while at the same time having excellent ionic conductivity.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical energy storage. Specifically, this invention relates to a transparent, flexible, glassy inorganic solid electrolyte and its preparation method. Background Technology

[0002] Given the rapid development of sodium-ion batteries, liquid electrolytes are not the best choice in terms of safety. Using new inorganic amorphous solid electrolytes to improve safety performance and energy density is currently a more promising approach.

[0003] Sodium-ion solid electrolytes can currently be classified into the following categories: oxides, sulfides, halides, organic polymers, and inorganic-organic composite solid electrolytes.

[0004] In terms of flexibility, organic polymers and inorganic-organic composite solid electrolytes have a natural advantage, as their organic segments give them good processability. Solid polymer electrolytes (PEO, polyethylene oxide) are crystalline at room temperature, but their low ionic conductivity is a drawback, and they require higher operating temperatures to maintain good ionic conductivity. Neither organic polymers nor inorganic-organic composite solid electrolytes meet the required light transmittance for practical applications.

[0005] Common oxide and sulfide solid electrolytes cannot meet the requirements, lacking both flexibility and light transmittance. Due to the lack of freely rotating chain segments in halide electrolytes, only a very small number of solid electrolytes can achieve light transmittance but lack flexibility; or they can be flexible but lack the transparency of glass.

[0006] Therefore, there is an urgent need for a solid electrolyte that is transparent and flexible at room temperature and also has excellent ionic conductivity. Summary of the Invention

[0007] The purpose of this invention is to provide a solid electrolyte that is transparent and flexible at room temperature, while also possessing excellent ionic conductivity. This solid electrolyte is amorphous in structure. Macroscopically, this solid electrolyte material maintains a polymeric softness and a glassy transparency at room temperature.

[0008] Another object of the present invention is to provide a method for preparing the solid electrolyte of the present invention.

[0009] The above-mentioned objective of the present invention is achieved through the following technical solution.

[0010] In the context of this invention, the term "room temperature" refers to 25°C to 35°C.

[0011] In a first aspect, the present invention provides a transparent, flexible, glassy inorganic solid electrolyte having the following chemical formula: NaAlO a Cl 4-2a -X x ;in,

[0012] X is selected from one or more of SeO2, TeO2 and GeO2;

[0013] 0.4≤a≤0.8, 0.01≤x≤0.1.

[0014] The inventors of this application unexpectedly discovered that the addition of Sb₂O₃ powder caused sodium tetrachloroaluminate (NaAlCl₄) crystals to form an amorphous structure, achieving polymer-like flexibility. Not wishing to be limited by theory, it is possible that the addition of Sb₂O₃ powder introduces oxygen bridges, connecting the originally isolated aluminum atoms, causing the sodium tetrachloroaluminate crystals to form chain segments and thus an amorphous structure, achieving polymer-like flexibility. In this invention, the Sb element volatilizes in the form of SbCl₃ and does not remain in the product.

[0015] The inventors of this application also unexpectedly discovered that the addition of X powder did not further alter the structure of the substrate. Instead, while maintaining high ionic conductivity and flexibility, it unexpectedly increased transparency, making it approach the transparency of glass. This is likely because the addition of X powder did not further alter the substrate structure, but rather acted as an additive, uniformly interspersed and dispersed within the chain segment network. Transparent solid electrolytes are advantageous for using optical characterization to investigate ion transport and visualize dendrite growth.

[0016] Preferably, in the transparent flexible glassy inorganic solid electrolyte of the present invention, 0.03 ≤ x ≤ 0.06.

[0017] Preferably, in the transparent flexible glassy inorganic solid electrolyte of the present invention, the ionic conductivity of the solid electrolyte is 10. -6 -2×10 -3 S / cm.

[0018] Preferably, in the transparent flexible glassy inorganic solid electrolyte of the present invention, the ionic conductivity of the solid electrolyte is 10. -4 -2×10 -3 S / cm.

[0019] Secondly, the present invention provides a method for preparing the transparent, flexible, glassy inorganic solid electrolyte of the present invention, which includes the following steps:

[0020] (1) Mix NaCl and AlCl3 powders evenly, heat to 200-500℃ and keep warm for 1-24 hours to obtain precursor NaAlCl4;

[0021] (2) The precursor NaAlCl4 is ground into powder and then mixed evenly with Sb2O3 powder. The mixture is heated to 200-400℃ and kept at that temperature for 1-5 hours to obtain the solid electrolyte NaAlO. a Cl 4-2a ;

[0022] (3) The solid electrolyte NaAlO a Cl 4-2a After grinding into powder, it is mixed evenly with powder X. The mixture is heated to 200-500℃ and kept at that temperature for 1-5 hours to obtain a transparent, flexible, glassy inorganic solid electrolyte NaAlO. a Cl 4-2a -X x ;

[0023] in,

[0024] X is selected from one or more of SeO2, TeO2 and GeO2;

[0025] 0.4≤a≤0.8, 0.01≤x≤0.1.

[0026] Preferably, in the method described in this invention, in step (1), NaCl and AlCl3 powders are uniformly mixed and heated to 200-250°C and kept at that temperature for 3-6 hours to obtain the precursor NaAlCl4.

[0027] Thirdly, the present invention provides a method for preparing the transparent, flexible, glassy inorganic solid electrolyte of the present invention, which includes the following steps:

[0028] (1) Mix NaCl and AlCl3 powders evenly, heat to 200-500℃ and keep warm for 1-24 hours to obtain precursor NaAlCl4;

[0029] (2) The precursor NaAlCl4 is ground into powder and then mixed evenly with Sb2O3 powder and X powder. The mixture is heated to 200-500℃ and kept at that temperature for 1-5 hours to obtain a transparent, flexible, glassy inorganic solid electrolyte NaAlO3. a Cl 4-2a -X x ;

[0030] in,

[0031] X is selected from one or more of SeO2, TeO2 and GeO2;

[0032] 0.4≤a≤0.8, 0.01≤x≤0.1.

[0033] The transparent, flexible, glassy inorganic solid electrolyte NaAlO in this invention a Cl 4-2a -X x It can be applied to sodium-ion all-solid-state batteries.

[0034] The present invention has the following beneficial effects:

[0035] (1) The transparent flexible glassy inorganic solid electrolyte NaAlO of the present invention a Cl 4-2a -X x It exhibits excellent machinability (i.e., flexibility) at room temperature. The low melting temperature allows the transparent, flexible glassy inorganic solid electrolyte of this invention to solve the cathode interface problem of the sodium-ion superconductor NASICON, resulting in good interface compatibility. Compared to polymer PEO (polyethylene oxide) electrolytes, the transparent, flexible glassy inorganic solid electrolyte of this invention can achieve an ionic conductivity of 10 at room temperature. -4 S / cm, even reaching 10 -3 The S / cm ratio ensures operation at room temperature. Furthermore, compared to sulfide amorphous solid electrolytes, the transparent, flexible, glassy inorganic solid electrolyte of this invention exhibits excellent oxidation resistance, will not be oxidized and decomposed by the positive electrode under high voltage operation, and is resistant to high oxidation potentials.

[0036] (2) The transparent flexible glassy inorganic solid electrolyte of the present invention has a simple preparation process and does not require a complicated preparation method like inorganic-organic composite solid electrolytes.

[0037] (3) The transparent flexible glassy inorganic solid electrolyte of the present invention also meets the requirement for transparency, which can greatly reduce the scattering of light by the material. Attached Figure Description

[0038] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings, wherein:

[0039] Figure 1 The solid electrolyte NaAlO prepared in Example 3 is shown. 0.69 Cl 2.6 -(SeO2) 0.03 The transparency test results, with a test wavelength of 532nm;

[0040] Figure 2 The solid electrolyte NaAlO prepared in Example 3 is shown. 0.69 Cl 2.6 -(SeO2) 0.03 Electrochemical performance when assembled into a solid-state battery;

[0041] Figure 3 The XRD patterns of the solid electrolytes prepared in Examples 1-7 are shown.

[0042] Figure 4 The solid electrolyte NaAlO prepared in Example 3 is shown. 0.69 Cl 2.6 -(SeO2) 0.03 It becomes a transparent material after solidification.

[0043] Figure 5 The solid electrolyte NaAlO prepared in Example 3 is shown. 0.69 Cl 2.6 -(SeO2) 0.03 Impedance diagram;

[0044] Figure 6 The solid electrolyte NaAlO prepared in Example 3 is shown. 0.69 Cl 2.6 -(SeO2) 0.03 EDS energy spectrum;

[0045] Figure 7 The solid electrolyte NaAlO prepared in Example 3 is shown. 0.69 Cl 2.6 -(SeO2) 0.03 SEM (Scanning Electron Microscopy) image;

[0046] Figure 8 The light transmittance of the solid electrolytes prepared in Example 4, Comparative Example 1 and Comparative Example 2 at wavelengths of 400-900 nm is shown.

[0047] Figure 9 The solid electrolyte NaAlO prepared in Comparative Example 1 is shown. 0.42 Cl 3.2 The transparency test results were obtained, with the test wavelength being 532nm. Detailed Implementation

[0048] The present invention will be further described in detail below with reference to specific embodiments. The embodiments given are only for illustrating the present invention and are not intended to limit the scope of the present invention.

[0049] The following embodiments and comparative examples of the present invention underwent some performance tests:

[0050] Ionic conductivity testing: First, the material is ground into powder, then pressed into a transparent, amorphous solid electrolyte sheet under certain pressure, and then tested using an electrochemical workstation. The test temperature is 35℃.

[0051] Transparency measurement: The material is first ground and crushed, then pressed into a transparent amorphous solid electrolyte sheet under certain pressure. The transparency of the transparent material is then determined by analyzing the transmitted light at each wavelength using a spectrophotometer.

[0052] LSV test: First, the material is ground and crushed, and then pressed into a transparent amorphous solid electrolyte sheet under a certain pressure. Then, sodium metal and carbon black positive electrodes (mixed with solid electrolyte) are placed on both sides of the transparent amorphous solid electrolyte sheet, and then the test is carried out through an electrochemical workstation.

[0053] Battery cycle testing: First, a transparent amorphous solid electrolyte film is rolled out. Then, the transparent amorphous solid electrolyte film is placed on a NASICON ceramic sheet, and the positive electrode is placed on the film. The film is melted and tightly bonded to the NASICON and the positive electrode through heat treatment. A sodium-tin alloy is placed on the other side of the NASICON ceramic sheet. The NSCION is then placed in a battery casing and sealed. Cyclic discharge testing is performed using Wuhan Landian Battery Testing Equipment under conditions of 0.3C and a voltage of 2.5-4.2V.

[0054] Example 1

[0055] NaAlO 0.48 Cl3-(SeO2) 0.03 Preparation

[0056] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained precursor NaAlCl4 was ground into powder and then uniformly mixed with Sb2O3 and SeO2 powders in a 1:0.16:0.03 molar ratio. The mixture was heated to 250℃ and held for 2 hours. After ICP analysis, the elemental content was measured to obtain a transparent, flexible, glassy inorganic solid electrolyte, NaAlO4. 0.48 Cl3-(SeO2) 0.03 .

[0057] The solid electrolyte of this embodiment has the following properties as measured:

[0058] Ionic conductivity at room temperature (35℃): 8×10 -4 S / cm;

[0059] Oxidation resistance potential: 4V;

[0060] Reduction potential: 0.6V;

[0061] Melting point: 150℃;

[0062] At room temperature, macroscopically it is transparent, glassy, ​​and flexible.

[0063] Example 2

[0064] NaAlO 0.6 Cl 2.8 -(SeO2) 0.03 Preparation

[0065] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained NaAlCl4 precursor was ground into powder and then uniformly mixed with Sb2O3 and SeO2 powders in a 1:0.2:0.03 molar ratio. The mixture was heated to 300℃ and held for 2 hours. After ICP analysis, the elemental content was measured to obtain a transparent, flexible, glassy inorganic solid electrolyte, NaAlO4. 0.6 Cl 2.8 -(SeO2) 0.03 .

[0066] Measurements showed that the amorphous solid electrolyte of this embodiment possesses the following properties:

[0067] Ionic conductivity at room temperature (35℃): 1×10 -3 S / cm;

[0068] Oxidation resistance potential: 4.1V;

[0069] Reduction potential: 0.8V;

[0070] Melting point: 200℃;

[0071] At room temperature, macroscopically it is transparent, glassy, ​​and flexible.

[0072] Example 3

[0073] NaAlO 0.69 Cl 2.6 -(SeO2) 0.03 Preparation

[0074] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained precursor NaAlCl4 was ground into powder and then uniformly mixed with Sb2O3 and SeO2 powders in a 1:0.23:0.03 molar ratio. The mixture was heated to 250℃ and held for 2 hours. After ICP analysis, the elemental content was measured to obtain a transparent, flexible, glassy inorganic solid electrolyte, NaAlO4. 0.69 Cl 2.6 -(SeO2) 0.03 .

[0075] Measurements showed that the amorphous solid electrolyte of this embodiment possesses the following properties:

[0076] Ionic conductivity at room temperature (35℃): 9×10 -4 S / cm;

[0077] Oxidation resistance potential: 4.3V;

[0078] Melting point: 250℃;

[0079] Reduction potential: 1V;

[0080] At room temperature, macroscopically: transparent, vitreous, flexible (e.g.) Figure 4 (As shown).

[0081] Figure 1 The solid electrolyte NaAlO prepared in Example 3 is shown. 0.69 Cl 2.6 -(SeO2) 0.03 The transparency test results were obtained, with the test wavelength being 532nm. Figure 1 The average light transmittance of the selected area is shown to be between 0.55 and 0.6, which is close to the transmittance of ordinary optical glass.

[0082] Figure 2 Example 3 shows the NaAlO obtained 0.69 Cl 2.6 -(SeO2) 0.03 All-solid-state battery assembled with transparent, flexible, glassy inorganic solid electrolyte: Na-Sn / / NASICON / / NaAlO 0.69 Cl 2.6 -(SeO2) 0.03 / / Electrochemical performance of NVOPF at 0.3C and 60℃. Figure 2 This demonstrates that, without additional treatment, the battery can operate normally at 60°C and 0.3C without short circuits or open circuits by simply combining the positive electrode, an amorphous solid electrolyte film, a NASICON ceramic sheet, and a sodium-tin alloy negative electrode. This indicates that the interface between the positive electrode and the NASICON electrolyte, after being treated with NaAlO4, is effectively controlled. 0.69 Cl 2.6 -(SeO2) 0.03 Improved contact ensures good battery operation.

[0083] Figure 3 The XRD structure diagram for this embodiment shows that, apart from a small number of lithium chloride impurity peaks, the rest are broad amorphous peaks.

[0084] Figure 4 The solid electrolyte NaAlO prepared in Example 3 is shown.0.69 Cl 2.6 -(SeO2) 0.03 It becomes a transparent material after solidification.

[0085] Figure 5 The solid electrolyte NaAlO prepared in Example 3 is shown. 0.69 Cl 2.6 -(SeO2) 0.03 Impedance diagram. Figure 5 It exhibits good ionic conductivity at room temperature.

[0086] Figure 6 The solid electrolyte NaAlO prepared in Example 3 is shown. 0.69 Cl 2.6 -(SeO2) 0.03 The EDS spectrum is shown. The spectrum reveals that the main elements Al, Na, O, and Se are uniformly distributed in the material, while Sb is almost entirely absent.

[0087] Figure 7 The solid electrolyte NaAlO prepared in Example 3 is shown. 0.69 Cl 2.6 -(SeO2) 0.03 The image shows a scanning electron microscope (SEM) image. As can be seen from the image, the obtained solid electrolyte has a smooth surface and good morphology.

[0088] Example 4

[0089] NaAlO 0.69 Cl 2.6 -(SeO2) 0.04 Preparation

[0090] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained precursor NaAlCl4 was ground into powder and then uniformly mixed with Sb2O3 and SeO2 powders in a 1:0.23:0.04 molar ratio. The mixture was heated to 250℃ and held for 2 hours. After ICP analysis, the elemental content was measured to obtain a transparent, flexible, glassy inorganic solid electrolyte, NaAlO4. 0.69 Cl 2.6 -(SeO2) 0.04 Its structure is shown in the appendix. Figure 3 .

[0091] Measurements showed that the amorphous solid electrolyte of this embodiment possesses the following properties:

[0092] Ionic conductivity at room temperature (35℃): 2×10 -3 S / cm;

[0093] Oxidation resistance potential: 3.9V;

[0094] Reduction potential: 1V;

[0095] Melting point: 300℃;

[0096] At room temperature, macroscopically it is transparent, glassy, ​​and flexible.

[0097] Example 5

[0098] NaAlO 0.69 Cl 2.6 -(SeO2) 0.05 Preparation

[0099] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained precursor NaAlCl4 was ground into powder and then uniformly mixed with Sb2O3 and SeO2 powders in a 1:0.23:0.05 molar ratio. The mixture was heated to 250℃ and held for 2 hours. After ICP analysis, the elemental content was measured to obtain a transparent, flexible, glassy inorganic solid electrolyte, NaAlO4. 0.69 Cl 2.6 -(SeO2) 0.05 .

[0100] Measurements showed that the amorphous solid electrolyte of this embodiment possesses the following properties:

[0101] Ionic conductivity at room temperature (35℃): 1×10 -3 S / cm;

[0102] Oxidation resistance potential: 4V;

[0103] Reduction potential: 0.8V;

[0104] Melting point: 270℃;

[0105] At room temperature, macroscopically it is transparent, glassy, ​​and flexible.

[0106] Example 6

[0107] NaAlO 0.69 Cl 2.6 -(GeO2) 0.045 Preparation

[0108] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained precursor NaAlCl4 was ground into powder and then uniformly mixed with Sb2O3 and GeO2 powders in a 1:0.23:0.045 molar ratio. The mixture was heated to 250℃ and held for 2 hours. After ICP analysis, the elemental content was measured to obtain a transparent, flexible, glassy inorganic solid electrolyte, NaAlO4. 0.69 Cl 2.6 -(GeO2) 0.045 .

[0109] Measurements showed that the amorphous solid electrolyte of this embodiment possesses the following properties:

[0110] Ionic conductivity at room temperature (35℃): 1.1 × 10⁻⁶ -3 S / cm;

[0111] Oxidation resistance potential: 3.8V;

[0112] Reduction potential: 1V;

[0113] Melting point: 270℃;

[0114] At room temperature, macroscopically: transparency decreases, it becomes glassy, ​​and it becomes flexible.

[0115] Example 7

[0116] NaAlO 0.69 Cl 2.6 -(GeO2) 0.05 -(SeO2) 0.05 Preparation

[0117] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained precursor NaAlCl4 was ground into powder and then uniformly mixed with Sb2O3, GeO2, and SeO2 powders in a molar ratio of 1:0.23:0.05:0.05. The mixture was heated to 250℃ and held for 2 hours. After ICP analysis, the elemental content was measured to obtain a transparent, flexible, glassy inorganic solid electrolyte, NaAlO4. 0.69 Cl 2.6 -(GeO2) 0.045 .

[0118] Measurements showed that the amorphous solid electrolyte of this embodiment possesses the following properties:

[0119] Ionic conductivity at room temperature (35℃): 0.7 × 10⁻⁶ -3 S / cm;

[0120] Oxidation resistance potential: 3.7V;

[0121] Reduction potential: 1V;

[0122] Melting point: 240℃;

[0123] At room temperature, macroscopically: transparency decreases, it becomes glassy, ​​and it becomes flexible.

[0124] Comparative Example 1

[0125] NaAlO 0.42 Cl 3.2 Preparation

[0126] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained precursor NaAlCl4 was ground into powder and then uniformly mixed with Sb2O3 powder in a 1:0.14 molar ratio. The mixture was heated to 250℃ and held for 2 hours. After ICP analysis, the elemental content was measured to obtain the flexible glassy inorganic solid electrolyte NaAlO3. 0.42 Cl 3.2 .

[0127] Measurements showed that the amorphous solid electrolyte in this comparative example possessed the following properties:

[0128] Ionic conductivity at room temperature (35℃): 1×10 -4 S / cm;

[0129] Oxidation resistance potential: 4.1V;

[0130] Reduction potential: 1.5V;

[0131] Melting point: 170℃;

[0132] At room temperature, macroscopically, the crystal has a partially ordered structure, slightly resembling clay, with significantly reduced transparency and no flexibility.

[0133] Figure 9 The solid electrolyte NaAlO prepared in Comparative Example 1 is shown. 0.42 Cl 3.2 The transparency test results were obtained, with the test wavelength being 532nm. Figure 9 The average light transmittance of the selected area is shown to be 0.28, which is only half that of Example 3 of the present invention. This indicates that the electrolyte has poor light transmittance when no X is added for modification.

[0134] This comparative example shows that when X is absent, the transparency of the solid electrolyte is greatly reduced and it lacks flexibility.

[0135] Comparative Example 2

[0136] NaAlO 0.75 Cl 2.5 Preparation

[0137] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained NaAlCl4 precursor was ground into powder and then uniformly mixed with Sb2O3 powder in a 1:0.25 molar ratio. The mixture was heated to 250℃ and held for 2 hours. After ICP analysis, the elemental content was measured to obtain the flexible glassy inorganic solid electrolyte NaAlO3. 0.75 Cl 2.5 .

[0138] Measurements showed that the amorphous solid electrolyte in this comparative example possessed the following properties:

[0139] Ionic conductivity at room temperature (35℃): 1×10 -3 S / cm;

[0140] Oxidation resistance potential: 4.2V;

[0141] Reduction potential: 1.7V;

[0142] Melting point: 250℃;

[0143] At room temperature, macroscopically: opaque, flexible.

[0144] This comparative example shows that when X is missing, although some solid electrolytes can be flexible, they still have low transparency.

[0145] Figure 8 The light transmittance of the solid electrolytes prepared in Example 4, Comparative Example 1, and Comparative Example 2 at wavelengths of 400-900 nm is shown in the figure. It can be seen from the figure that the unmodified original material has lower transparency, significantly different from that of the standard glass sample.

[0146] Comparative Example 3

[0147] NaAlO 0.9 Cl 2.2 -(SeO2) 0.03 Preparation

[0148] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained precursor NaAlCl4 was ground into powder and then uniformly mixed with Sb2O3 and SeO2 powders in a 1:0.3:0.03 molar ratio. The mixture was heated to 250℃ and held for 2 hours. After ICP analysis, the elemental content was measured to obtain the flexible glassy inorganic solid electrolyte NaAlO. 0.9 Cl 2.2 -(SeO2) 0.03 .

[0149] Measurements showed that the amorphous solid electrolyte in this comparative example possessed the following properties:

[0150] Ionic conductivity at room temperature (35℃): 0.7 × 10⁻⁶ -3 S / cm;

[0151] Oxidation resistance potential: 4.15V;

[0152] Reduction potential: 1.5V;

[0153] Melting point: 250℃;

[0154] At room temperature, macroscopically: opaque, loss of flexibility.

[0155] This comparative example shows that when the O content is too high, the solid electrolyte becomes opaque and loses its flexibility.

[0156] Comparative Example 4

[0157] NaAlO 0.6 Cl 2.8 -(SeO2) 0.12 Preparation

[0158] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained precursor NaAlCl4 was ground into powder and then uniformly mixed with Sb2O3 and SeO2 powders in a 1:0.2:0.12 molar ratio. The mixture was heated to 250℃ and held for 2 hours. After ICP analysis, the elemental content was measured to obtain the flexible glassy inorganic solid electrolyte NaAlO. 0.6 Cl 2.8 -(SeO2) 0.12 .

[0159] Measurements showed that the amorphous solid electrolyte in this comparative example possessed the following properties:

[0160] Ionic conductivity at room temperature (35℃): 0.3 × 10⁻⁶ -3 S / cm;

[0161] Oxidation resistance potential: 4V;

[0162] Reduction potential: 1.5V;

[0163] Melting point: 250℃;

[0164] At room temperature, macroscopically: opaque, loss of flexibility.

[0165] This comparative example shows that when there is too much SeO2, the solid electrolyte becomes opaque and loses its flexibility.

[0166] Comparative Example 5

[0167] NaAlCl4-(SeO2) 0.03 Preparation

[0168] NaCl and AlCl3 powders were uniformly mixed and ground in a 1:1 molar ratio, then placed in a muffle furnace and heated to 200℃ for 3 hours to obtain a homogeneous precursor NaAlCl4. The obtained NaAlCl4 precursor was ground into powder and then uniformly mixed with SeO2 powder in a 1:0.03 molar ratio. The mixture was heated to 250℃ and held for 2 hours. The elemental content was measured by ICP analysis to obtain the flexible glassy inorganic solid electrolyte NaAlCl4. 4- (SeO2) 0.03 .

[0169] Measurements showed that the amorphous solid electrolyte in this comparative example possessed the following properties:

[0170] Ionic conductivity at room temperature (35℃): 0.3 × 10⁻⁶ -4 S / cm;

[0171] Oxidation resistance potential: 3.8V;

[0172] Reduction potential: 1V;

[0173] Melting point: 200℃;

[0174] At room temperature, macroscopically: opaque, loss of flexibility.

[0175] This comparative example shows that when Sb2O3 is not added, both the transparency and flexibility of the solid electrolyte are lost.

Claims

1. A transparent, flexible, glassy inorganic solid electrolyte having the following chemical formula: NaAlO a Cl 4-2a -X x ;in, X is selected from one or more of SeO2, TeO2 and GeO2; 0.4≤a≤0.8, 0.01≤x≤0.

1.

2. The transparent flexible glassy inorganic solid electrolyte according to claim 1, wherein, 0.03≤x≤0.06。 3. The transparent flexible glassy inorganic solid electrolyte according to claim 1, wherein, The ionic conductivity of the solid electrolyte is 10. -6 -2×10 -3 S / cm.

4. The transparent flexible glassy inorganic solid electrolyte according to claim 1, wherein, The ionic conductivity of the solid electrolyte is 10. -4 -2×10 -3 S / cm.

5. A method for preparing a transparent, flexible, glassy inorganic solid electrolyte according to any one of claims 1-4, comprising the following steps: (1) Mix NaCl and AlCl3 powders evenly, heat to 200-500℃ and keep warm for 1-24 hours to obtain precursor NaAlCl4; (2) The precursor NaAlCl4 is ground into powder and then mixed evenly with Sb2O3 powder. The mixture is heated to 200-400℃ and kept at that temperature for 1-5 hours to obtain the solid electrolyte NaAlO. a Cl 4-2a ; (3) The solid electrolyte NaAlO a Cl 4-2a After grinding into powder, it is mixed evenly with powder X. The mixture is heated to 200-500℃ and kept at that temperature for 1-5 hours to obtain a transparent, flexible, glassy inorganic solid electrolyte NaAlO. a Cl 4-2a -X x ; in, X is selected from one or more of SeO2, TeO2 and GeO2; 0.4≤a≤0.8, 0.01≤x≤0.

1.

6. The method according to claim 5, wherein, In step (1), NaCl and AlCl3 powders are uniformly mixed and heated to 200-250℃ and kept at that temperature for 3-6 hours to obtain the precursor NaAlCl4.

7. A method for preparing a transparent, flexible, glassy inorganic solid electrolyte according to any one of claims 1-4, comprising the following steps: (1) Mix NaCl and AlCl3 powders evenly, heat to 200-500℃ and keep warm for 1-24 hours to obtain precursor NaAlCl4; (2) The precursor NaAlCl4 is ground into powder and then mixed evenly with Sb2O3 powder and X powder. The mixture is heated to 200-500℃ and kept at that temperature for 1-5 hours to obtain a transparent, flexible, glassy inorganic solid electrolyte NaAlO3. a Cl 4-2a -X x ; in, X is selected from one or more of SeO2, TeO2 and GeO2; 0.4≤a≤0.8, 0.01≤x≤0.1.

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