An oxyhalide solid-state electrolyte material, and a preparation method and application thereof

Abstract

The application belongs to the technical field of battery materials, and particularly relates to an oxyhalide solid electrolyte material and a preparation method and application thereof. The preparation method comprises the following steps: mixing ZrCl4 and LiOH under the protection of an inert atmosphere; putting the obtained mixture and zirconia balls into a zirconia jar, and ball milling under the protection of an inert atmosphere to obtain LiZr 1.25 OC14 powder; adding LiBr powder into the LiZr 1.25 OC14 powder, and continuously ball milling under the protection of an inert atmosphere to obtain a LiZr 1.25 OC14-xLiBr primary sample; heating, heat preservation and cooling of the primary sample in a vacuum sealed quartz tube, grinding, and obtaining a LiZr 1.25 OC14-xLiBr powder material. The LiBr doping is performed on the LiZr 1.25 OC14 material, and heat treatment is performed, so that the ionic conductivity and cycle stability of the halide solid electrolyte of the lithium battery are improved, the preparation method is simple, the cost is low, no waste water and waste gas are generated, and the industrial implementation is easy.

Description

Technical Field

[0001] This invention belongs to the field of battery materials technology, and specifically relates to an oxygen halide solid electrolyte material, its preparation method, and its application. Background Technology

[0002] All-solid-state lithium batteries (ASSLBs) have been widely used due to their high energy density and high safety. Solid electrolytes (SEs) are a key component of ASSLBs, and halide solid electrolytes have received much attention in recent years. However, existing halide solid electrolytes mainly suffer from insufficient ionic conductivity and poor cycle stability, which seriously affects the efficient application of solid electrolytes.

[0003] Chinese invention patent CN119591155A discloses a method for preparing an oxychloride electrolyte material, the material itself, and an all-solid-state battery. The method includes: providing raw materials, which include a metal chloride and lithium hydroxide; and reacting the metal chloride with lithium hydroxide in an inert gas atmosphere to obtain the oxychloride electrolyte material. Using lithium hydroxide as the lithium raw material is inexpensive, reducing preparation costs. Hydrogen chloride is generated during the mixing process, providing an acidic catalytic environment and shortening the preparation time. Furthermore, the prepared oxychloride electrolyte material incorporates oxygen and chlorine elements, and the oxychloride framework structure formed by these elements is a clearly flexible ionic framework structure. This ionic framework structure reduces the lithium-ion diffusion activation energy, thereby improving the room-temperature ionic conductivity of the oxychloride electrolyte material. However, the metal chlorides targeted in this patent are tantalum chloride and niobium chloride, which are expensive raw materials, hindering large-scale commercialization. Without doping and heat treatment, the electrochemical performance of the resulting electrolyte material is generally poor. Summary of the Invention

[0004] To address the shortcomings of existing methods, this invention provides an oxyhalide solid electrolyte material, its preparation method, and its applications.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A method for preparing an oxygen halide solid electrolyte material includes the following steps:

[0007] (1) Mix ZrCl4 and LiOH under an inert atmosphere;

[0008] (2) The mixture obtained in step (1) and the zirconia balls were placed in a zirconia jar and ball-milled under an inert atmosphere to obtain LiZr. 1.25 OCl4 powder;

[0009] (3) The LiZr obtained in step (2)1.25 LiBr powder was added to OCl4 powder and ball-milled further under an inert atmosphere to obtain LiZr. 1.25 Initial sample of OCl4-xLiBr;

[0010] (4) Take the LiZr obtained in step (3) 1.25 The initial OCl4-xLiBr sample was heated, held at that temperature, cooled, and ground in a vacuum-sealed quartz tube to obtain LiZr. 1.25 OCl4-xLiBr powder material, where x represents the mixture of LiBr powder and LiZr. 1.25 Mass percentage of OCl4 powder.

[0011] Preferably, the molar ratio of ZrCl4 to LiOH in step (1) is 1-1.5:1.

[0012] Preferably, the mass ratio of the zirconia balls to the raw materials in step (2) is 10-20:1.

[0013] Preferably, the ball milling speed in step (2) or (3) is 500-1000 rpm and the ball milling time is 5-10 h.

[0014] Preferably, the LiBr powder and LiZr powder in step (3) 1.25 The mass ratio of OCl4 powder is 4%-10%, where x = 4%-10%.

[0015] Preferably, the heating rate in step (4) is 5-20℃ / min, the heating temperature is 180-200℃, and the holding time is 1-3h.

[0016] An oxygen halide solid electrolyte material prepared by the above preparation method.

[0017] Application of an oxygen halide solid electrolyte material prepared by the above preparation method in all-solid-state lithium batteries.

[0018] The positive and beneficial effects of this invention are as follows:

[0019] 1. This invention uses LiZr 1.25 Using OCl4 solid electrolyte material as the substrate medium, LiBr powder was incorporated, and LiZr was synthesized under mechanical ball milling and heat treatment conditions. 1.25 OCl4-xLiBr solid electrolyte powder, compared to LiZr 1.25 OCl4 solid electrolyte material, LiZr prepared 1.25 OCl4-xLiBr solid electrolyte powder exhibits high ionic conductivity and better cycle stability. This invention utilizes the properties of LiZr... 1.25LiBr doping of OCl4 material improves the ionic conductivity of lithium-ion battery halide solid electrolytes, among which LiZr... 1.25 OCl4-10%LiBr showed the best improvement in ionic conductivity. Furthermore, heat treatment lowered its activation energy and significantly improved its cycle stability, further enhancing its ionic conductivity. This provides a new approach and method for preparing oxyhalide solid electrolytes with high ionic conductivity and high cycle stability. In addition, the solid electrolyte material preparation method of this invention is simple, low-cost, and generates no wastewater or waste gas, making it easy to implement industrially and widely applicable in the field of all-solid-state lithium batteries. Attached Figure Description

[0020] Figure 1 The LiZr prepared in Examples 1-6 1.25 XRD comparison of OCl4-xLiBr.

[0021] Figure 2 The LiZr prepared in Examples 1-6 1.25 EIS comparison of OCl4-xLiBr.

[0022] Figure 3 Examples 1 and 4, 7 show the LiZr before and after heat treatment. 1.25 XRD comparison of OCl4-xLiBr.

[0023] Figure 4 Examples 1 and 4, 7 show the LiZr before and after heat treatment. 1.25 EIS comparison of OCl4-xLiBr.

[0024] Figure 5 The LiZr prepared in Example 1 1.25 EIS plot of OCl4 at varying temperatures.

[0025] Figure 6 The LiZr prepared in Example 4 1.25 EIS plot of OCl4-10%LiBr at varying temperatures.

[0026] Figure 7 The LiZr prepared in Example 7 1.25 EIS diagram of OCl4-10%LiBr heat treatment at varying temperatures.

[0027] Figure 8 Examples 1 and 4, 7 show the LiZr before and after heat treatment. 1.25 Comparison of activation energies of OCl4-xLiBr.

[0028] Figure 9 The LiZr prepared in Example 7 1.25Lithium symmetric cycling diagram after OCl4-10%LiBr heat treatment. Detailed Implementation

[0029] The present invention will be further described below with reference to some specific embodiments.

[0030] Example 1

[0031] A method for preparing an oxygen halide solid electrolyte material includes the following steps:

[0032] Take 1.75g ​​ZrCl4 powder and 0.144g LiOH powder (molar ratio of 1.25:1) in an agate mortar and grind manually for 10 minutes in a glove box filled with argon.

[0033] The ground powder was transferred to a zirconia vacuum ball mill jar, and 30g of zirconia grinding balls with a diameter of 5mm were added. The mass ratio of zirconia balls to raw material was 15:1. After sealing, the ball mill jar was filled with argon gas and milled at 500rpm for 10 hours. After milling, LiZr was obtained. 1.25 OCl4 sample.

[0034] Example 2

[0035] A method for preparing an oxygen halide solid electrolyte material includes the following steps:

[0036] Take 1.75g ​​ZrCl4 powder and 0.144g LiOH powder (molar ratio of 1.25:1) in an agate mortar and grind manually for 10 minutes in a glove box filled with argon.

[0037] The ground powder was transferred to a zirconia vacuum ball mill jar and 30g of zirconia grinding balls with a diameter of 5mm were added. The mass ratio of zirconia balls to raw materials was 15:1. After sealing, the ball mill jar was filled with argon gas and milled at 500rpm for 10h.

[0038] After finishing, open the ball mill jar and add 0.07576g of LiBr (LiZr). 1.25 The mass ratio of OCl4 powder to LiBr powder was 1:0.04. After resealing, the mixture was ball-milled at 500 rpm for 10 hours in an argon-filled environment. After ball milling, the obtained LiZr was collected. 1.25 OCl4-4%LiBr solid electrolyte material.

[0039] Example 3

[0040] A method for preparing an oxygen halide solid electrolyte material includes the following steps:

[0041] Take 1.75g ​​ZrCl4 powder and 0.144g LiOH powder (molar ratio of 1.25:1) in an agate mortar and grind manually for 10 minutes in a glove box filled with argon.

[0042] The ground powder was transferred to a zirconia vacuum ball mill jar and 30g of zirconia grinding balls with a diameter of 5mm were added. The mass ratio of zirconia balls to raw materials was 15:1. After sealing, the ball mill jar was filled with argon gas and milled at 500rpm for 10h.

[0043] After finishing, open the ball mill jar and add 0.1326g of LiBr (LiZr). 1.25 The mass ratio of OCl4 powder to LiBr powder was 1:0.07. After resealing, the mixture was ball-milled at 500 rpm for 10 hours in an argon-filled environment. After ball milling, the obtained LiZr was collected. 1.25 OCl4-7%LiBr solid electrolyte material.

[0044] Example 4

[0045] A method for preparing an oxygen halide solid electrolyte material includes the following steps:

[0046] Take 1.75g ​​ZrCl4 powder and 0.144g LiOH powder (molar ratio of 1.25:1) in an agate mortar and grind manually for 10 minutes in a glove box filled with argon.

[0047] The ground powder was transferred to a zirconia vacuum ball mill jar and 30g of zirconia grinding balls with a diameter of 5mm were added. The mass ratio of zirconia balls to raw materials was 15:1. After sealing, the ball mill jar was filled with argon gas and milled at 500rpm for 10h.

[0048] After finishing, open the ball mill jar and add 0.1894g of LiBr (LiZr). 1.25 The mass ratio of OCl4 powder to LiBr powder was 1:0.1. After resealing, the mixture was ball-milled at 500 rpm for 10 hours in an argon-filled environment. After ball milling, the obtained LiZr was collected. 1.25 OCl4-10%LiBr solid electrolyte material.

[0049] Example 5

[0050] A method for preparing an oxygen halide solid electrolyte material includes the following steps:

[0051] Take 1.75g ​​ZrCl4 powder and 0.144g LiOH powder (molar ratio of 1.25:1) in an agate mortar and grind manually for 10 minutes in a glove box filled with argon.

[0052] The ground powder was transferred to a zirconia vacuum ball mill jar and 30g of zirconia grinding balls with a diameter of 5mm were added. The mass ratio of zirconia balls to raw materials was 15:1. After sealing, the ball mill jar was filled with argon gas and milled at 500rpm for 10h.

[0053] After finishing, open the ball mill jar and add 0.2462g of LiBr (LiZr). 1.25 The mass ratio of OCl4 powder to LiBr powder was 1:0.13. After resealing, the mixture was ball-milled at 500 rpm for 10 hours in an argon-filled environment. After ball milling, the obtained LiZr was collected. 1.25 OCl4-13%LiBr solid electrolyte material.

[0054] Example 6

[0055] A method for preparing an oxygen halide solid electrolyte material includes the following steps:

[0056] Take 1.75g ​​ZrCl4 powder and 0.144g LiOH powder (molar ratio of 1.25:1) in an agate mortar and grind manually for 10 minutes in a glove box filled with argon.

[0057] The ground powder was transferred to a zirconia vacuum ball mill jar and 30g of zirconia grinding balls with a diameter of 5mm were added. The mass ratio of zirconia balls to raw materials was 15:1. After sealing, the ball mill jar was filled with argon gas and milled at 500rpm for 10h.

[0058] After finishing, open the ball mill jar and add 0.2841g of LiBr (LiZr). 1.25 The mass ratio of OCl4 powder to LiBr powder was 1:0.15. After resealing, the mixture was ball-milled at 500 rpm for 10 hours in an argon-filled environment. After ball milling, the obtained LiZr was collected. 1.25 OCl4-15%LiBr solid electrolyte material.

[0059] Example 7

[0060] A method for preparing an oxygen halide solid electrolyte material includes the following steps:

[0061] Take 1.75g ​​ZrCl4 powder and 0.144g LiOH powder (molar ratio of 1.25:1) in an agate mortar and grind manually for 10 minutes in a glove box filled with argon.

[0062] The ground powder was transferred to a zirconia vacuum ball mill jar and 30g of zirconia grinding balls with a diameter of 5mm were added. The mass ratio of zirconia balls to raw materials was 15:1. After sealing, the ball mill jar was filled with argon gas and milled at 500rpm for 10h.

[0063] After finishing, open the ball mill jar and add 0.1894g of LiBr (LiZr). 1.25 The mass ratio of OCl4 powder to LiBr powder was 1:0.1. After resealing, the mixture was ball-milled at 500 rpm for 10 hours in an argon-filled environment. After ball milling, the obtained LiZr was collected. 1.25 OCl4-10%LiBr initial sample;

[0064] The initial sample was placed in a quartz tube, vacuum sealed, and heated to 200°C in a tube furnace at a heating rate of 5°C / min. It was then held at this temperature for 3 hours. After the holding period, the vacuum quartz tube was immediately removed and immersed in a beaker containing liquid nitrogen. Once cooling was complete, the sample was ground to obtain LiZr. 1.25 OCl4-10%LiBr heat-treated solid electrolyte material.

[0065] Performance testing

[0066] In an argon-filled glove box, take an appropriate amount of the prepared, untreated LiZr. 1.25 OCl4-x%LiBr powder was evenly spread in the central groove of the XRD anaerobic cell and sealed with high-temperature resistant tape. Each sealed XRD anaerobic cell was then tested using an Empyrean X-ray diffractometer at a scan rate of 20° / min and a scan range of 10°–75°. The test results are shown below. Figure 1 and 3 ;

[0067] Weigh 100 mg of the LiZr prepared in the corresponding example. 1.25 OCl4-xLiBr powder samples were pressed into solid discs with a diameter of 1 cm. These discs were placed between two stainless steel rods and assembled into a mold battery in an argon-filled glove box. Performance testing was then conducted, and the results are shown below. Figure 2 , 4 -8.

[0068] Weigh 100 mg of LiZr prepared in Example 7 1.25 OCl4-10%LiBr heat-treated powder samples were pressed into solid discs with a diameter of 1 cm. These discs were then placed between two lithium discs of the same diameter of 1 cm and assembled into button batteries in an argon-filled glove box. Figure 9 A 0.1mAh coin cell battery at 0.1mA / cm 2Cyclic performance graph obtained from current density testing.

[0069] Figure 1 For LiZr 1.25 OCl4-xLiBr (x is 4%-15%) and LiZr 1.25 The XRD pattern of OCl4 clearly shows that LiZr doped with LiBr... 1.25 The peak intensity of LiCl in OCl4 decreased, and the overall XRD peaks were amorphous, indicating that the doping of LiBr reduced the peak intensity of LiZr. 1.25 The amorphousness of OCl4 is enhanced.

[0070] Figure 2 For LiZr 1.25 OCl4-xLiBr (x is 4%-15%) and LiZr 1.25 The EIS comparison chart of OCl4, tested under the conditions of a frequency range of 0.1-100000Hz and a voltage amplitude of 5mV, shows that doping with 10% LiBr affects the performance of LiZr. 1.25 OCl4 showed the best impedance reduction and the greatest increase in ionic conductivity, providing a clear target for heat treatment in subsequent modification experiments.

[0071] Figure 3 Whether or not LiZr is heat-treated 1.25 OCl4-10%LiBr and LiZr 1.25 The XRD patterns of OCl4 clearly show that the heat-treated LiZr... 1.25 OCl4-10%LiBr exhibits a relatively weak ZrO2 peak, but the overall state remains amorphous.

[0072] Figure 4 Whether or not LiZr is heat-treated 1.25 OCl4-10%LiBr and LiZr 1.25 The EIS comparison chart of OCl4, tested under the conditions of a frequency range of 0.1-100000Hz and a voltage amplitude of 5mV, shows that LiZr 1.25 The ionic conductivity of OCl4 is 3.26 × 10⁻⁶. -4 S cm -1 After heat treatment, LiZr 1.25 The ionic conductivity of OCl4-10%LiBr is 1.01 × 10⁻⁶. -3 S cm -1 LiZr after heat treatment 1.25 OCl4-10%LiBr further improved the ionic conductivity, increasing it from the order of magnitude of 10. -4 Upgraded to 10 -3 This is more conducive to the transport of lithium ions.

[0073] Figure 5-7 The figures show the temperature-dependent EIS curves of the corresponding batteries tested at frequencies ranging from 0.1 to 100,000 Hz, voltage amplitudes of 5 mV, and temperatures ranging from 30 to 80 °C. Figure 5 For LiZr 1.25 EIS comparison chart of OCl4 at varying temperatures. Figure 6 For LiZr 1.25 Temperature-dependent EIS comparison chart of OCl4-10%LiBr Figure 7 LiZr after heat treatment 1.25 Temperature-dependent EIS comparison of OCl4-10%LiBr, by Figure 5 It can be seen that LiZr 1.25 The impedance of OCl4 decreases with increasing temperature. Figure 6 It can be seen that LiZr 1.25 The impedance of OCl4-10%LiBr decreases with increasing temperature. Figure 7 It can be seen that after heat treatment, LiZr 1.25 The impedance of OCl4-10%LiBr decreases with increasing temperature.

[0074] Figure 8 Whether or not LiZr is heat-treated 1.25 OCl4-10%LiBr and LiZr 1.25 The activation energy comparison chart of OCl4, tested under the conditions of frequency range 0.1-100000Hz, voltage amplitude 5mV, and temperature range 30-80℃, clearly shows that the heat-treated LiZr 1.25 OCl4-10%LiBr has a lower activation energy, less resistance to lithium ion migration within it, higher transport efficiency, and better performance.

[0075] Figure 9 LiZr after heat treatment 1.25 The lithium symmetric cycling diagram of OCl4-10%LiBr shows that no short circuit occurred after nearly 1800 hours of cycling, indicating that there are few side reactions between it and lithium metal and that it has good stability during cycling.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solutions of the present invention, as long as they do not depart from the spirit and scope of the technical solutions of the present invention, should be covered within the scope of the claims of the present invention.

Claims

1. A method for preparing an oxyhalide solid electrolyte material, characterized in that, Includes the following steps: (1) Mix ZrCl4 and LiOH under an inert atmosphere; (2) The mixture obtained in step (1) and the zirconia balls were placed in a zirconia jar and ball-milled under an inert atmosphere to obtain LiZr. 1.25 OCl4 powder; (3) Apply the LiZr obtained in step (2) 1.25 LiBr powder was added to OCl4 powder and ball-milled further under an inert atmosphere to obtain LiZr. 1.25 Initial sample of OCl4-xLiBr; (4) Take the LiZr obtained in step (3) 1.25 The initial OCl4-xLiBr sample was heated and held at a temperature in a vacuum-sealed quartz tube. After the holding period, the vacuum quartz tube was immediately removed and immersed in a beaker containing liquid nitrogen for cooling. After cooling was complete, the sample was ground to obtain LiZr. 1.25 OCl4-xLiBr powder material, where x represents the mixture of LiBr powder and LiZr. 1.25 The mass percentage of OCl4 powder, where x = 4%-10%.

2. The method for preparing the oxyhalide solid electrolyte material according to claim 1, characterized in that, The molar ratio of ZrCl4 to LiOH in step (1) is 1-1.5:

1.

3. The method for preparing the oxyhalide solid electrolyte material according to claim 1, characterized in that, The mass ratio of the zirconia balls to the raw materials in step (2) is 10-20:

1.

4. The method for preparing the oxyhalide solid electrolyte material according to claim 1, characterized in that, The ball milling speed in step (2) or (3) is 500-1000 rpm and the ball milling time is 5-10 h.

5. The method for preparing the oxyhalide solid electrolyte material according to claim 1, characterized in that, The heating rate in step (4) is 5-20℃ / min, the heating temperature is 180-200℃, and the holding time is 1-3h.

6. An oxyhalide solid electrolyte material prepared by the preparation method according to any one of claims 1-5.

7. The application of an oxyhalide solid electrolyte material prepared by the preparation method according to any one of claims 1-5 in an all-solid-state lithium battery.

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