A LATP solid electrolyte and its preparation method and use

Abstract

The present invention belongs to the field of battery materials technology and provides a LATP solid electrolyte, its preparation method, and use. The preparation method comprises dry-mixing a LATP solid raw material, an inorganic weak acid powder, and an organic alcohol powder, wherein the organic alcohol powder comprises at least one of polyvinyl alcohol, polyethylene glycol, or polypropylene alcohol, to obtain a mixed material; and sintering the mixed material to obtain the LATP solid electrolyte. By using the organic alcohol powder and the inorganic weak acid powder to neutralize the acidity and alkalinity of the phosphorus and lithium sources, an efficient, mild, and uniform reaction is effectively ensured. By replacing the long wet ball milling process with a dispersion medium with dry mixing, the uneven dispersion and segregation of the various raw materials caused by the organic dispersion medium are avoided, as well as the amplified particle size differences of the raw materials caused by long ball milling, effectively improving the consistency of the raw materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery materials and relates to a LATP solid electrolyte and a preparation method and application thereof. Background Art

[0002] Lithium-ion batteries, with their advantages of high operating voltage, high energy density, and long cycle life, are currently widely used in vehicle power, energy storage grids, and consumer electronics. To further meet market demand for lithium-ion batteries, developing lithium-ion batteries with higher energy density, improved safety, and longer cycle life has become imperative. Semi-solid, quasi-solid, and all-solid-state batteries, which use solid-state electrolytes to completely or partially replace liquid electrolytes, have become a research priority due to their advantages, such as energy density up to 500 Wh / kg, higher safety, and longer cycle life.

[0003] Among solid electrolytes, LATP solid electrolyte (lithium aluminum titanium phosphate) has the advantages of low cost, good environmental adaptability, and high ionic conductivity. It has made significant progress in industrialization. The theoretical ionic conductivity of LATP solid electrolyte can be as high as 1×10 -3 S / cm, which basically meets the requirements of all-solid-state batteries for electrolyte performance. However, the ionic conductivity of the LATP solid electrolyte actually prepared so far is only 1×10 -4 S / cm, which is far lower than the theoretical value. The low actual conductivity will seriously affect the lithium ion migration rate inside the solid electrolyte, hindering the development of solid-state battery technology.

[0004] To address this issue, the traditional improved process uses ethanol ball milling-calcination for high-entropy doping to prepare high-performance LATP solid electrolytes. However, this solution has the problem that the calcination and ball milling processes take too long, and the ball milling process of each substance easily causes the difference in the state of the raw materials to increase, the particle size ratio to be unbalanced, and thus causes uneven distribution. In addition, high-entropy element doping also amplifies the hazards of uneven element distribution, resulting in poor consistency and stability of product performance. In addition, due to the different acidity and alkalinity of lithium salts, phosphates and other oxide raw materials in the raw materials, local reactions are very likely to occur during the mixing process, which will also lead to deterioration of product performance.

[0005] Therefore, exploring new methods to synthesize high-performance LATP solid electrolytes has important practical significance. Summary of the Invention

[0006] In view of the problems existing in the prior art, the present invention aims to provide a LATP solid electrolyte and its preparation method and use. The preparation method comprises dry-mixing LATP solid raw materials, inorganic weak acid powder, and organic alcohol powder to obtain a mixed material; and sintering the mixed material to obtain the LATP solid electrolyte. By using organic alcohol powder and inorganic weak acid powder to neutralize the acidity and alkalinity of the phosphorus source and lithium source, an efficient, mild, and uniform reaction is effectively ensured. By replacing the long wet ball milling process with a dispersion medium with dry mixing, the uneven dispersion and segregation of the various raw materials caused by the organic dispersion medium are avoided, as well as the amplification of raw material particle size differences caused by long ball milling, effectively improving the consistency of the raw materials.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a method for preparing a solid electrolyte, the preparation method comprising:

[0009] LATP solid raw material, inorganic weak acid powder and organic alcohol powder are dry-mixed to obtain a mixed material; and the mixed material is sintered to obtain a LATP solid electrolyte.

[0010] The preparation method described herein utilizes an acid-base balance-assisted method to synthesize LATP solid electrolytes. By using inorganic weak acid powder and organic alcohol powder as acid-base balance auxiliary materials, the inorganic weak acid reduces the alkalinity of the lithium source (e.g., lithium carbonate) in the LATP solid raw material, and the organic alcohol powder locks in the phosphorus source (e.g., phosphate) in the LATP solid raw material, reducing local reactions and moderating the intensity of the acid-base reaction. This ensures uniform mixing and a mild, efficient, and uniform reaction. Furthermore, by replacing the conventional method of long-term liquid-phase ball milling in a dispersion medium with a specific dry mixing method, problems such as segregation, incomplete reaction, and side reactions caused by uneven distribution of multiple substances can be effectively avoided. Furthermore, the method effectively shortens mixing time, achieving rapid mixing in a short period of time and avoiding damage to the materials caused by long-term ball milling, which can lead to increased material variability. This preparation method is simple to operate, fast to produce, and easily scalable. It can also produce high-performance LATP solid electrolyte products with high ionic conductivity, promising broad prospects.

[0011] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following technical solutions, the technical objectives and beneficial effects of the present invention can be better achieved and realized.

[0012] As a preferred technical solution of the present invention, based on the mass of the LATP solid raw material as 100%, the mass of the inorganic weak acid powder accounts for 0.1% to 1.5%, for example, 0.1%, 0.12%, 0.15%, 0.18%, 0.2%, 0.23%, 0.25%, 0.28%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.2%, 1.5%, etc., preferably 0.2% to 1.4%, more preferably 0.4% to 1.2%.

[0013] As a preferred technical solution of the present invention, the inorganic weak acid powder includes at least one of boric acid, silicic acid, metasilicic acid or oxalic acid.

[0014] Preferably, the particle size D of the inorganic weak acid powder is 50 It is 10nm~50μm, for example, 10nm, 25nm, 50nm, 75nm, 100nm, 300nm, 500nm, 800nm, 1μm, 3μm, 5μm, 8μm, 10μm, 13μm, 15μm, 18μm, 20μm, 23μm, 25μm, 28μm, 30μm, 33μm, 35μm, 38μm, 40μm, 45μm, 48μm or 50μm, etc.

[0015] As a preferred technical solution of the present invention, based on the mass of the LATP solid raw material as 100%, the mass of the organic alcohol powder accounts for 0.1% to 1.5%, for example, 0.1%, 0.12%, 0.15%, 0.18%, 0.2%, 0.23%, 0.25%, 0.28%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.2%, 1.5%, etc., preferably 0.2% to 1.4%, and more preferably 0.4% to 1.2%.

[0016] Preferably, the organic alcohol powder includes at least one of polyvinyl alcohol, polyethylene glycol or polypropylene alcohol.

[0017] Preferably, the particle size D of the organic alcohol powder is 50 It is 10nm~50μm, for example, 10nm, 25nm, 50nm, 75nm, 100nm, 300nm, 500nm, 800nm, 1μm, 3μm, 5μm, 8μm, 10μm, 13μm, 15μm, 18μm, 20μm, 23μm, 25μm, 28μm, 30μm, 33μm, 35μm, 38μm, 40μm, 45μm, 48μm or 50μm, etc.

[0018] In the present invention, the reactivity of the organic alcohol powder increases during the sintering process, but its molecular weight has little effect on the acid-base reaction. The more common and commonly used molecular weights of each substance can be applied to the present invention, but ultra-high molecular weights far exceeding the common market level should not be used. For example, the common molecular weight of polyvinyl alcohol is 16,000 to 200,000, while polyvinyl alcohol with an ultra-high degree of polymerization greater than 200,000 should not be used.

[0019] As a preferred technical solution of the present invention, the LATP solid raw material includes a lithium source, an aluminum source, a titanium source and a phosphorus source.

[0020] Preferably, the lithium source includes at least one of lithium carbonate, lithium hydroxide or lithium oxide.

[0021] Preferably, the aluminum source comprises aluminum oxide and / or aluminum hydroxide.

[0022] Preferably, the titanium source comprises titanium dioxide and / or titanate.

[0023] Preferably, the phosphorus source includes at least one of ammonium dihydrogen phosphate, diammonium hydrogen phosphate or ammonium phosphate.

[0024] Preferably, the mass amount of the lithium source is in excess of 1% to 50%, for example, 1%, 3%, 5%, 8%, 10%, 13%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 33%, 35%, 38%, 40%, 42%, 45%, 48% or 50%.

[0025] Preferably, the particle size D of the LATP solid raw material is 50 It is 10nm~100μm, for example, 10nm, 25nm, 50nm, 75nm, 100nm, 300nm, 500nm, 800nm, 1μm, 3μm, 5μm, 8μm, 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 45μm, 50μm, 55μm, 60μm, 65μm, 70μm, 75μm, 80μm, 85μm, 90μm, 95μm or 100μm, etc.

[0026] As a preferred technical solution of the present invention, the dry mixing process includes first pre-dry mixing the inorganic weak acid powder with the lithium source to obtain a mixture A, and simultaneously pre-dry mixing the organic alcohol powder with the phosphorus source to obtain a mixture B, and then dry mixing the mixture A, the mixture B, the aluminum source and the titanium source to obtain the mixed material;

[0027] Preferably, the time for the first pre-dry mixing and the second pre-dry mixing is ≤2h, for example, 2h, 1.8h, 1.5h, 1.3h, 1h, 0.8h, 0.5h, 0.3h, 0.2h, 0.1h, 5min, 3min or 1min, etc., preferably 1min~1h, more preferably 1min~5min.

[0028] As a preferred technical solution of the present invention, the dry mixing time is ≤4h, for example, 4h, 3.8h, 3.5h, 3.3h, 3h, 2.8h, 2.5h, 2.3h, 2h, 1.8h, 1.5h, 1.3h, 1h, 0.8h, 0.5h, 0.3h, 0.2h or 0.1h, 5min, 3min or 1min, etc., preferably 1min~3h, more preferably 2min~10min.

[0029] Preferably, the equipment used for the dry mixing includes at least one of an agate mortar, a small juicer, a Chinese medicine mixer, a ball mill, a V-shaped mixer or a high-pressure mixer.

[0030] As a preferred technical solution of the present invention, the sintering temperature is 800~1000℃, for example, 800℃, 830℃, 850℃, 880℃, 900℃, 920℃, 940℃, 960℃, 980℃ or 1000℃, and the sintering time is 2~6h, for example, 2h, 2.3h, 2.5h, 2.8h, 3h, 3.2h, 3.5h, 3.8h, 4h, 4.2h, 4.5h, 4.8h, 5h, 5.3h, 5.5h, 5.8h or 6h, etc.

[0031] Preferably, the equipment used for the sintering includes at least one of a box furnace, a muffle furnace, a tube furnace, a pusher kiln or a roller kiln.

[0032] In a second aspect, the present invention provides a LATP solid electrolyte obtained according to the preparation method described in the first aspect.

[0033] Preferably, the particle size D of the LATP solid electrolyte is 50 It is 50nm~10μm, for example, 50nm, 65nm, 75nm, 85nm, 95nm, 100nm, 150nm, 230nm, 300nm, 360nm, 420nm, 500nm, 660nm, 740nm, 800nm, 850nm, 900nm, 960nm, 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, 7μm, 8μm, 9μm or 10μm, etc.

[0034] In a third aspect, the present invention provides a battery comprising the LATP solid electrolyte described in the second aspect.

[0035] It should be noted that due to space limitations and to avoid redundancy, the present invention does not exhaustively list all point values ​​within the above numerical range, but is not limited to the listed values. Other unlisted values ​​within the above numerical range are also applicable.

[0036] Compared with the existing technical solutions, the present invention has at least the following beneficial effects:

[0037] The preparation method of the present invention is beneficial to reducing local reactions, mitigating the intensity of acid-base reactions, ensuring uniform mixing, and reacting mildly, efficiently, and uniformly by using inorganic weak acid powder and organic alcohol powder as auxiliary materials for acid-base balance, thereby ensuring uniform mixing, and a mild, efficient, and uniform reaction. At the same time, by replacing the long-term liquid-phase ball milling method in the dispersion medium in the prior art with a specific dry mixing method, the problems of segregation, insufficient reaction, or side reactions caused by uneven distribution of various substances can be effectively avoided. The mixing time can be effectively shortened, and rapid mixing can be achieved in a short time, avoiding damage to the material caused by long-term ball milling, resulting in increased material differences. The preparation method is simple to operate, has a fast production speed, is easy to amplify, and can obtain a high-performance LATP solid electrolyte product with high ionic conductivity, which has broad prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is the EIS test graph of the LATP solid electrolyte obtained in Example 1.

[0039] Figure 2 This is the EIS test graph of the LATP solid electrolyte obtained in Example 4.

[0040] Figure 3 This is the EIS test graph of the LATP solid electrolyte obtained in Example 12.

[0041] Figure 4 This is the EIS test graph of the LATP solid electrolyte obtained in Comparative Example 1.

[0042] Figure 5 This is the EIS test graph of the LATP solid electrolyte obtained in Comparative Example 2.

[0043] Figure 6 This is the EIS test graph of the LATP solid electrolyte obtained in Comparative Example 3. DETAILED DESCRIPTION

[0044] The technical solution of the present invention is further illustrated below through specific implementation methods.

[0045] It should be apparent to those skilled in the art that the embodiments are only intended to help understand the present invention and should not be considered as specific limitations of the present invention.

[0046] Example 1

[0047] This embodiment provides a method for preparing a LATP solid electrolyte, the preparation method comprising:

[0048] Weigh 2640g of lithium carbonate, 770g of aluminum oxide, 6790g of titanium dioxide, 17250g of ammonium dihydrogen phosphate, 210g of boric acid and 210g of polyvinyl alcohol in solid powder form. The particle size D of lithium carbonate, aluminum oxide, titanium dioxide and ammonium dihydrogen phosphate is 50 The particle size of boric acid is between 10nm and 100μm. 50 In the range of 10nm~50μm, the particle size of polyvinyl alcohol is D 50 The particle size ranges from 10 nm to 50 μm. That is, based on the total mass of lithium carbonate, aluminum oxide, titanium dioxide, and ammonium dihydrogen phosphate as 100%, the mass of boric acid accounts for 0.77%, and the mass of polyvinyl alcohol accounts for 0.77%. The lithium carbonate and boric acid are pre-dry-mixed for 3 minutes to form mixture A. At the same time, ammonium dihydrogen phosphate and polyvinyl alcohol are pre-dry-mixed for only 3 minutes to form mixture B. Mixture A, mixture B, and the remaining raw materials are placed in a high-speed mixer and dry-mixed for 5 minutes. The mixing is then completed to obtain a mixed material. The resulting mixed material is placed in a sagger and sintered in a sintering furnace. The sintering temperature is set at 900°C and the sintering time is 4 hours to obtain the LATP solid electrolyte.

[0049] Example 2

[0050] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, the mass of boric acid is adjusted from 210 g to 15 g, so that the mass proportion of boric acid is adjusted from 0.77% to 0.055%. Except for the above, other conditions are exactly the same as those in Example 1.

[0051] Example 3

[0052] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, the mass of boric acid is adjusted from 210 g to 60 g, so that the mass proportion of boric acid is adjusted to 0.22%. Except for the above, other conditions are exactly the same as those in Example 1.

[0053] Example 4

[0054] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, the mass of boric acid is adjusted from 210 g to 120 g, so that the mass proportion of boric acid is adjusted to 0.44%. Except for the above, other conditions are exactly the same as those in Example 1.

[0055] Example 5

[0056] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, the mass of boric acid is adjusted from 210 g to 240 g, so that the mass proportion of boric acid is adjusted to 0.87%. Except for the above, other conditions are exactly the same as those in Example 1.

[0057] Example 6

[0058] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, the mass of boric acid is adjusted from 210 g to 480 g, so that the mass proportion of boric acid is adjusted to 1.74%. Except for the above, other conditions are exactly the same as those in Example 1.

[0059] Example 7

[0060] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, the mass of polyvinyl alcohol is adjusted from 210 g to 10 g, so that the mass proportion of polyvinyl alcohol is adjusted from 0.77% to 0.04%. Except for the above, other conditions are exactly the same as those in Example 1.

[0061] Example 8

[0062] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, the mass of polyvinyl alcohol is adjusted from 210 g to 60 g, so that the mass proportion of polyvinyl alcohol is adjusted from 0.77% to 0.22%. Except for the above, other conditions are exactly the same as those in Example 1.

[0063] Example 9

[0064] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, the mass of polyvinyl alcohol is adjusted from 210 g to 120 g, so that the mass proportion of polyvinyl alcohol is adjusted to 0.44%. Except for the above, other conditions are exactly the same as those in Example 1.

[0065] Example 10

[0066] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, the mass of polyvinyl alcohol is adjusted from 210 g to 240 g, so that the mass proportion of polyvinyl alcohol is adjusted from 0.77% to 0.87%. Except for the above, other conditions are exactly the same as those in Example 1.

[0067] Example 11

[0068] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, the mass of polyvinyl alcohol is adjusted from 210 g to 480 g, so that the mass proportion of polyvinyl alcohol is adjusted to 1.74%. Except for the above, other conditions are exactly the same as those in Example 1.

[0069] Example 12

[0070] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, boric acid is replaced by oxalic acid, and polyvinyl alcohol is replaced by polyethylene glycol. Except for the above, other conditions are exactly the same as those in Example 1.

[0071] Example 13

[0072] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, boric acid is replaced by metasilicic acid, and polyvinyl alcohol is replaced by polypropylene alcohol. Except for the above, other conditions are exactly the same as those in Example 1.

[0073] Example 14

[0074] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, boric acid is replaced by silicic acid, and polyvinyl alcohol is replaced by polyethylene glycol. Except for the above, other conditions are exactly the same as those in Example 1.

[0075] Example 15

[0076] This embodiment provides a method for preparing a LATP solid electrolyte. In the preparation method, lithium carbonate, aluminum oxide, titanium dioxide, ammonium dihydrogen phosphate, boric acid, and ammonium dihydrogen phosphate are simultaneously added to a high-pressure mixer and dry-mixed for 8 minutes to obtain the mixed material. Except for the above, other conditions are exactly the same as those in Example 1.

[0077] Comparative Example 1

[0078] This comparative example provides a method for preparing a LATP solid electrolyte. The preparation method does not use the boric acid and the ammonium dihydrogen phosphate. Except for the above, other conditions are exactly the same as those in Example 1.

[0079] Comparative Example 2

[0080] This comparative example provides a method for preparing a LATP solid electrolyte. The preparation method does not use the ammonium dihydrogen phosphate. Except for the above, other conditions are exactly the same as those in Example 1.

[0081] Comparative Example 3

[0082] This comparative example provides a method for preparing a LATP solid electrolyte, wherein the preparation method does not use boric acid. Except for the above, other conditions are exactly the same as those in Example 1.

[0083] Comparative Example 4

[0084] This comparative example provides a preparation method of LATP solid electrolyte, wherein lithium carbonate, aluminum oxide, titanium dioxide, ammonium dihydrogen phosphate, boric acid and ammonium dihydrogen phosphate are wet ball-milled, ethanol is used as a dispersion medium, the ball-milling time is 6 hours, and after drying and crushing, a mixed material is obtained. Except for the above, the other conditions are exactly the same as those in Example 1.

[0085] The particle size D of the LATP solid electrolyte obtained in the embodiment and the comparative example was measured. 50 test.

[0086] The ionic conductivity of the LATP solid electrolyte obtained in the embodiment and the comparative example was tested. The LATP solid electrolyte powder was die-cast into an electrolyte sheet at a certain pressure, and then the electrolyte sheet was sintered into a dense ceramic sheet. After gold spraying or brushing with conductive silver paste on both sides, an EIS test was performed using an electrochemical workstation to obtain its resistance value R. The ionic conductivity was calculated according to the formula σ=L / (R×S), where L is the thickness of the electrolyte sheet during the test (cm) and S is the area of ​​the electrolyte sheet during the test (cm). 2 ).

[0087] Figures 1 to 6 The EIS test graphs of the LATP solid electrolytes obtained in Example 1, Example 4, Example 12, and Comparative Examples 1, 2, and 3 are respectively shown. After obtaining the resistance value, the ionic conductivity is calculated according to the formula. The obtained results and the results obtained in other examples are recorded in Table 1.

[0088] Table 1

[0089]

[0090] Table 1 shows that, when acid-base balance auxiliary materials are used, LATP electrolyte materials with high conductivity and low particle size can be obtained, which facilitates the application of LATP electrolyte materials. However, adding too much or too little acid-base auxiliary materials will lead to varying degrees of reduced conductivity and increased particle size.

[0091] In summary, the preparation method of the present invention is beneficial to reducing local reactions, mitigating the intensity of acid-base reactions, ensuring uniform mixing, and reacting mildly, efficiently, and uniformly by using inorganic weak acid powder and organic alcohol powder as acid-base balance auxiliary materials. At the same time, by replacing the long-term liquid-phase ball milling method in the dispersion medium in the prior art with a specific dry mixing method, the problems of segregation, insufficient reaction, or side reactions caused by uneven distribution of multiple substances can be effectively avoided. It can also effectively shorten the mixing time, achieve rapid mixing in a short time, and avoid long-term ball milling causing damage to the material, resulting in increased material differences. The preparation method is simple to operate, has a fast production speed, is easy to scale up, and can obtain a high-performance LATP solid electrolyte product with high ionic conductivity, which has broad prospects. The preparation method of the present invention is of great significance for the synthesis of LATP through acid-base synchronous assistance, and the prepared nano-LATP is of great significance in the fields of positive electrode material coating and organic-inorganic composite electrolytes.

[0092] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0093] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0094] In addition, the various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A method for preparing a LATP solid electrolyte, characterized in that: The preparation method comprises: LATP solid raw material, inorganic weak acid powder, and organic alcohol powder are dry-mixed, and the dry-mixing equipment is at least one of a V-shaped mixer and a high-pressure mixer to obtain a mixed material; based on the mass of the LATP solid raw material being 100%, the mass of the inorganic weak acid powder accounts for 0.1% to 1.5%; based on the mass of the LATP solid raw material being 100%, the mass of the organic alcohol powder accounts for 0.1% to 1.5%; the LATP solid raw material comprises a lithium source, an aluminum source, a titanium source, and a phosphorus source; the inorganic weak acid powder comprises at least one of boric acid, silicic acid, or metasilicic acid; the organic alcohol powder comprises at least one of polyvinyl alcohol, polyethylene glycol, or polypropylene alcohol; the lithium source comprises at least one of lithium carbonate, lithium hydroxide, or lithium oxide; and the phosphorus source comprises at least one of ammonium dihydrogen phosphate, diammonium hydrogen phosphate, or ammonium phosphate; The dry mixing process includes first pre-dry mixing the inorganic weak acid powder with the lithium source to obtain mixture A, and simultaneously pre-dry mixing the organic alcohol powder with the phosphorus source to obtain mixture B, and then dry mixing the mixture A, the mixture B, the aluminum source and the titanium source to obtain the mixed material; and sintering the mixed material to obtain the LATP solid electrolyte.

2. The method for preparing the LATP solid electrolyte according to claim 1, wherein The particle size D of the inorganic weak acid powder 50 10nm~50μm.

3. The preparation method of LATP solid electrolyte according to claim 1, characterized in that, The particle size D of the organic alcohol powder 50 10nm~50μm.

4. The method for preparing the LATP solid electrolyte according to claim 1, wherein The aluminum source includes aluminum oxide and / or aluminum hydroxide; the titanium source includes titanium dioxide and / or titanate; The mass amount of the lithium source is in excess of 1% to 50%; The particle size D of the LATP solid raw material 50 10nm~100μm.

5. The method for preparing the LATP solid electrolyte according to claim 4, wherein The time for the first pre-dry mixing and the second pre-dry mixing is ≤ 2 hours.

6. The method for preparing the LATP solid electrolyte according to claim 1 or 5, wherein: The dry mixing time is ≤4h.

7. The method for preparing the LATP solid electrolyte according to claim 1, wherein The sintering temperature is 800-1000°C and the sintering time is 2-6 hours; The equipment used for the sintering includes at least one of a box furnace, a muffle furnace, a tube furnace, a pusher kiln or a roller kiln.

8. A LATP solid electrolyte, characterized in that Obtained according to the preparation method according to any one of claims 1 to 7.

9. The LATP solid electrolyte according to claim 8, characterized in that The particle size D of the LATP solid electrolyte 50 50nm~10μm.

10. A battery, characterized in that: Contains the LATP solid electrolyte according to claim 8 or 9.

Images