Solid-state battery compound solid electrolytes, composite electrolytes and environmentally friendly battery utilization

Abstract

This application belongs to the field of solid-state batteries, and particularly relates to a solid-state battery compound solid-state electrolyte, a composite solid-state electrolyte, and environmentally friendly battery utilization. The solid-state battery compound solid-state electrolyte is characterized by the following general formula: AwBxCyDz, where A contains one or more of Li, Na, K, Ca, Mg, Fe, Cu, V, and Cr; B contains one or more of La, Sr, Y, Ba, Ga, Bi, Ce, Sm, Pr, Nd, Al, Ni, and Co; C contains one or more of Zr, Nb, Ti, Ta, Mo, Rh, Ir, Pt, Sb, Sc, Zn, Ru, W, Mn, Si, and P; and D contains one or more of F, Cl, Br, I, O, and S, wherein 1≤w≤8, 0≤x≤5, 0≤y≤4, and 0≤z≤15. The solid-state battery compound solid-state electrolyte of this application is easily prepared into suitable films or exhibits high conductivity or can be combined with other electrolytes to achieve similar effects.

Description

Technical Field

[0001] This application belongs to the field of solid-state batteries, and particularly relates to a solid-state battery compound solid-state electrolyte, a composite solid-state electrolyte, and the environmentally friendly utilization of batteries. Background Technology

[0002] Solid-state batteries and their electrolytes offer advantages such as high energy density, enhanced safety, significantly reduced negative electrode material usage, and smaller size, minimizing the need for separators and electrolytes in traditional batteries. The distance between the positive and negative electrodes in solid-state batteries can be reduced to just a few to tens of micrometers, drastically reducing battery thickness. This leads to the prospect of miniaturization, thin-film production, and flexibility. Solid-state batteries are also safer, potentially solving the problems of lithium dendrite formation and separator puncture leading to short circuits in traditional lithium batteries. Furthermore, solid-state batteries promise to address the issues of organic liquid electrolytes in traditional batteries, which are prone to side reactions, oxidation, decomposition, gas generation, and combustion at high temperatures. Additionally, the large amount of valuable metal components in traditional electrolyte lithium batteries entering the environment poses serious harm to humans and the environment. Meanwhile, lithium, cobalt, and nickel are scarce metals with high demand, making the recycling and reuse of metals from traditional electrolyte batteries an urgent issue. Therefore, finding efficient and cost-effective recycling and environmentally friendly methods for the green and sustainable development of lithium batteries is the right path.

[0003] Solid-state battery compounds and solid electrolytes have good chemical stability. Because they are relatively stable in air and do not easily undergo chemical reactions, they can maintain good performance even in high-temperature or harsh environments, thereby improving battery safety and lifespan. However, existing solid-state battery compounds and solid electrolytes are brittle and difficult to fabricate suitable films. They also have poor compatibility with electrodes or other electrolytes, low conductivity at room temperature, and lack the necessary raw materials for their preparation. Summary of the Invention

[0004] To address one of the aforementioned problems, this application provides a solid-state battery compound solid electrolyte, the compound having the general formula: AwBxCyDz, wherein A comprises one or more of Li, Na, K, Ca, Mg, Fe, Cu, V, and Cr; B comprises one or more of La, Sr, Y, Ba, Ga, Bi, Ce, Sm, Pr, Nd, Al, Ni, and Co; C comprises one or more of Zr, Nb, Ti, Ta, Mo, Rh, Ir, Pt, Sb, Sc, Zn, Ru, W, Mn, Si, and P; and D comprises one or more of F, Cl, Br, I, O, and S, wherein 1≤w≤8, 0≤x≤5, 0≤y≤4, and 0≤z≤15.

[0005] Preferably, the compound includes Li7La3Zr2O12 LiNi 0.8 Co 0.1 Mn 0.1 O2, containing Li 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 One or more of the compounds.

[0006] A method for preparing a solid-state battery compound solid electrolyte, containing Li 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.0 5O 11.99 F 0.02 The preparation method of the compound is as follows:

[0007] According to the molar ratio of Li:Na:K:Al:La:Zr:Si:F of 70:0.8:4:0.4:30:19.5:0.5:0.22, weigh out Li₂CO₃, K₂O, Na₂O, Al(OH)₃, La(NO₃)₃·6H₂O, Zr(NO₃)₄, C₈H₂O, and F. 21 NSi, (C 13 H 14 F3NO2)n or powder A are added sequentially with stirring to deionized water, the pH is adjusted to 5-7 to form a solution, heated and stirred to form a gel, dried and pulverized into powder, and then the powder is sintered at 1000-1200°C to become a Li-containing powder. 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.9 9F 0.02 The compound is denoted as powder B.

[0008] Furthermore, the Li-containing 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 Preparation of the compound, wherein the Li-containing compound 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr1.95 Si 0.05 O 11.99 F 0.02 The preparation of the compound includes by means of the (C) 13 H 14 The process of shaping F3NO2)n or powder A into a branched mesh.

[0009] Preferably, the Li2CO3 preparation adopts a method for the recovery and extraction of lithium, cobalt, and nickel from lithium batteries, including the first step: recovery and extraction of non-lithium valuable metals; and the second step: lithium recovery.

[0010] Preferably, the one containing (C) 13 H 14 The preparation method of substance F3NO2)n involves dissolving 1-(3,4-difluorophenyl)prop-2-en-1-amine and (E)-4-fluorobut-2-enoic acid in an aqueous solution at a molar ratio of 1:1.

[0011] This application also provides a composite solid electrolyte, comprising a combination of any solid-state battery compound solid electrolyte and the aforementioned polymer solid electrolyte, wherein the polymer solid electrolyte comprises a chemical formula (C... 13 H 14 Substances containing F3NO2)n or substances containing molecular structural formula I.

[0012] Preferably, a composite solid electrolyte, wherein the combination includes a compound and a polymer solid electrolyte matched and composited, or the polymer solid electrolyte is used to form a branched network of the compound before being matched and composited.

[0013] Preferably, the matching composite includes a branched network containing Li. 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.0 5O 11.99 F 0.02 Compound powder and polymer solid electrolyte powder are matched and composited to form a film.

[0014] This application also provides a method for preparing a composite solid electrolyte, wherein a certain amount of powder A is prepared into a solution with deionized water, lithium carbonate is added according to the mass ratio, and the solution is heated until the pH no longer decreases. Then, powder B is added according to the mass ratio and stirred to form a uniform gel. The gel is then coated and dried, and the gel is recorded as a film.

[0015] This application also provides a compound solid-state or composite solid-state battery, comprising at least one type of solid electrolyte.

[0016] The beneficial effects of this application are that the solid-state battery compound solid electrolyte of this application has at least one of the following effects.

[0017] Solid-state battery compounds and solid electrolytes are easy to prepare into suitable films or have high conductivity, or they can be combined with other electrolytes to achieve good results.

[0018] 1. Solid-state battery compound solid electrolyte disc b is easy to prepare a suitable film. Furthermore, the solid-state battery compound solid electrolyte disc b has a soft branched network structure. The disc shows a 0.1 mm indentation to a certain depth, which is attributed to the elastic shrinkage of its branched network structure.

[0019] 2. The solid-state battery compound solid electrolyte wafer b has high conductivity. Furthermore, the small arcs appearing on the solid-state battery compound solid electrolyte wafer b reflect the high conductivity of Li. 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 The compound material has good ion diffusion and migration capabilities, and at least the modification and doping of Na, K, Al, Si, O and F have certain beneficial effects on the material.

[0020] 3. Solid-state battery compounds: Solid electrolytes are easily combined with other electrolytes. Specifically, substances containing structural formula I have spatially distinct amine groups, fluoride ions, carboxyl groups, etc., which are beneficial to Li-containing compounds. 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.9 9F 0.02 The spatial structure of solid-state battery compounds and solid electrolytes, along with their combination or interaction with lithium, makes it easier to match and combine them in a composite manner, resulting in a synergistic gain effect in conductivity results. Attached Figure Description

[0021] Figure 1 This is a graph showing the test results of the cobalt recovery control agent in this application;

[0022] Figure 2 The infrared spectrum of solid electrolyte membrane a in a polymer solid-state battery is shown.

[0023] Figure 3 Electron micrographs of compound solid electrolyte powder B and composite solid electrolyte membrane b;

[0024] Figure 4 XRD pattern of compound solid electrolyte powder B;

[0025] Figure 5Impedance spectra of disc b and control disc prepared for compound solid electrolyte powder B at room temperature. Detailed Implementation

[0026] The method for recovering and extracting lithium, cobalt, and nickel from lithium batteries includes the following steps: Step 1: Recovery and extraction of non-lithium valuable metals: In 100ml of acid solution, add 3-10% lithium-containing solid powder raw material (preferably waste batteries containing lithium, nickel, and cobalt). Adjust the pH to below 5 and stir at room temperature until the content of nickel, cobalt, and manganese ions in the solution no longer increases. Then, add 1-3 moles of ammonia and ammonium ions (ammonium chloride is preferred, with a molar ratio of ammonia to ammonium chloride of 2:1). The molar ratio of ammonia to ammonium ions is 1:1-3. Control the pH at 8-9 and stir at 30-70℃ for 10-120 minutes. After filtration, collect the precipitate containing high-valence heavy metal ions. Then, add 0.1-0.3g of sodium hydroxide to the filtrate and filter to separate and collect the cobalt-containing precipitate. Next, add 0.1-0.3g of sodium hydroxide to the filtrate and filter to separate and collect the nickel-containing precipitate. Slowly add phosphoric acid to the filtrate, controlling the pH to 6-8, and filter to separate the ferric phosphate precipitate. Use at least two identical cuvettes (preferably 10mm) to take filtrate samples, designating them as test sample cuvettes and control sample cuvettes respectively. Add cobalt recovery control agent (0.005-0.02g) in parallel to both cuvettes. A solution of 0.02% cobalt recovery control agent (preferably added in 0.1-0.5 ml) is prepared. The pH of the liquid in the test sample cuvette is controlled to not exceed 10. The reaction is allowed to proceed for 30 minutes, and the absorbance is measured at 520 μm using a spectrophotometer. Similarly, the pH of the liquid in the control sample cuvette is controlled to not exceed 3. The reaction is allowed to proceed for 30 minutes, and the absorbance is measured at 520 μm using a spectrophotometer. When the difference between the absorbance of the test sample and the control sample is less than 0.25, it indicates that the cobalt content in the filtrate is less than 0.1%. Then, the lithium recovery step is performed. If the difference between the absorbance of the test sample and the absorbance of the control sample is greater than 0.25, the steps before taking the filtrate sample need to be repeated until the difference between the absorbance of the test sample and the absorbance of the control sample in the filtrate is less than 0.25 (in the above test, the same test results were obtained by replacing the cobalt recovery control agent with 5-Cl-PADAB at 1.25 times the cobalt recovery control dose. Therefore, in the non-lithium valuable metal recovery and extraction step, the cobalt recovery control agent can be replaced by 5-Cl-PADAB). The method of this application recovers cobalt and nickel sequentially and controls the cobalt recovery to a filtrate content of less than 0.1%.

[0027] The second step is the lithium recovery step. In the filtrate after the first step of valuable metal recovery and extraction, 0.02-2% carbonic acid is added, heated and stirred until precipitation occurs, and the filtrate is filtered to separate the remaining manganese. Then, at least 0.02% carbonic acid is added to the filtrate to completely precipitate the lithium, and the filtrate is dried to obtain the finished lithium carbonate product.

[0028] The content analysis of the lithium carbonate obtained in the second step showed that its calcium content was less than 0.02% by mass, the heavy metal content (calculated as lead) was less than 0.001% by mass, and other impurities were not lower than those of analytically pure lithium carbonate. Therefore, the lithium carbonate prepared in this application is beneficial for use as a raw material for the preparation of lithium batteries or solid-state lithium batteries. Preferably, the lithium carbonate prepared above is used as a raw material for the preparation of polymer solid-state battery electrolytes or solid-state electrolytes of substance or compound of structural formula I.

[0029] Furthermore, this method also includes a third step: the separation and recycling of the cobalt recovery control agent. This involves repeatedly collecting the sample solution containing the cobalt recovery control agent after the first step (i.e., collecting the liquid containing the cobalt recovery control agent in a cuvette). Preferably, at least 3 kg of the sample solution is collected during industrial production. The sample solution is filtered using (3-micron) filter paper to separate the cobalt recovery control agent after the reaction. The separated cobalt recovery control agent is then repeatedly rinsed with an acid solution with a pH not exceeding 3. Simultaneously, the cobalt content in the rinsing solution is tested using a spectrophotometer. If the test results show the presence of cobalt ions, rinsing and testing continue until the cobalt ion content in the rinsing solution no longer increases. The rinsed cobalt recovery control agent is then dried, granulated, and reused. (The cobalt ion content in the solution after ignition of the cobalt recovery control agent is then measured using atomic absorption spectrometry, indicating that the cobalt recovery control agent can be regenerated with an acid solution with a pH not exceeding 3 after absorbing cobalt ions.) This method is beneficial for resource recovery and reducing environmental pollution. In the third step, 5-Cl-PADAB cannot be used to replace the cobalt recovery control agent. Furthermore, the acid solution used to immerse the lithium-containing solid raw material in the first step of this invention can be the leaching solution after rinsing. More preferably, the lithium-containing solid raw material and the acid solution react in a countercurrent manner to achieve countercurrent leaching of metals from the lithium solid raw material. The method of this invention is beneficial for the environmentally friendly recycling of valuable metals from waste batteries. The recycling process has low energy consumption, requires small amounts of acid, is highly efficient and fast, the recycling method is easy to master, and the impurities in the recycled product are stably controlled, which is beneficial for use as a raw material in battery manufacturing. The recycling process is environmentally friendly and efficient. The hydrochloric acid involved in the above steps can also be the recycled hydrochloric acid involved in this application. The pH of the raw material hydrochloric acid involved in this application cannot exceed 1.8.

[0030] The following describes the process of treating or recovering hydrochloric acid from the gas generated in the acid produced in this application, including but not limited to the following scheme: The waste gas contains a small amount of partially absorbed HCl waste gas. This waste gas is collected and sucked into a storage tank. If the waste gas does not meet the emission standards, when treating the waste gas that does not meet the emission requirements, since the treatment of hydrochloric acid waste gas is water absorption and alkali absorption, generally when treating hydrochloric acid waste gas with a high concentration, water is absorbed into hydrochloric acid. The hydrochloric acid recovered from this waste gas can be reused. The reused hydrochloric acid is called recovered hydrochloric acid. If an unexpected situation occurs and it cannot be reused, then in order to ensure that the emission standards are met, alkali is added for absorption. The water or alkali absorbed above is the absorption liquid.

[0031] The absorption process can be handled using jet spraying equipment, a device that utilizes the energy of a high-speed jet stream to transport waste gas and absorb liquid. In jet spraying equipment, high-pressure liquid converts liquid energy into kinetic energy through nozzles, thereby transporting the gas-liquid mixture to the next treatment device or system. During the treatment process, waste gas first enters the jet spraying equipment through one or more nozzles. At the nozzles, high-pressure liquid mixes with the waste gas. The high-pressure liquid contains water to absorb the liquid, and hydrogen chloride in the waste gas readily combines with the absorbent liquid to form hydrochloric acid. The high-speed flow energy of the liquid absorbs harmful substances in the waste gas. Then, the gas-liquid mixture enters a diffuser, where kinetic energy is converted into pressure energy, thus achieving further treatment of the waste gas. After jet treatment, the HCl content in the waste gas can be recycled or reduced to meet emission standards.

[0032] This application also provides a method for preparing a cobalt recovery control agent.

[0033] 0.5 mol of 5-Cl-PADAB was added to a three-necked flask containing 50 ml of methanol solution, followed by 0.8 mol of (1-chlorovinyl)cyclopropane. The mixture was stirred at 0–25 °C for 3 h, kept at 30 °C for 3 h, and then allowed to stand at 35 °C with frequent stirring for 12 h. After heating and filtration to separate the methanol-containing solution, C was obtained. 16 H 16 ClN5, C 16 H 16 ClN5 was added to methanol to prepare a 30% solution. Then, 0.05% azobisisobutyronitrile (AIBN) was added, and the mixture was heated under nitrogen gas until it became viscous. After testing, the molecular weight was determined to be not less than 1 million. Granulation and drying were then performed, followed by infrared spectroscopy testing. The cobalt recovery control agent test results are as follows: Figure 1 ,Depend on Figure 1As can be seen from the above, the characteristic absorption of chlorine-containing groups is at 600-700 cm⁻¹ and 1000-1300 cm⁻¹, azobenzene at 1570-1550 cm⁻¹ and 323 cm⁻¹, the absorption peak of pyridine is located at 1580 cm⁻¹, and no large olefin absorption waves are observed at 2930 cm⁻¹ and 2850 cm⁻¹, indicating that the double chemical bond is open. The absorption wavelengths of diamines are at 3500-3150 cm⁻¹ and 1350-1100 cm⁻¹, and cyclopropane in the infrared is at 3310-3000 cm⁻¹. From the above analysis, it can be concluded that the formation of molecules with the molecular formula [C 16 H 16 ClN5]n or substances containing the following structural formula II,

[0034]

[0035] Use [C] 16 H 16 ClN5]n replaces 5-Cl-PADAB in the cobalt reagent spectrophotometric method in GB / T 4325.8-2013 for testing alloy steel containing 0.05% cobalt. 16 H 16 The same effect was achieved when the amount of ClN5]n was 80% of that of 5-Cl-PADAB, with a repeatability limit of 0.0007%. Furthermore, the analytical task was performed at least due to the presence of diamine and cyclopropane structures, using the [C]n described in this application. 16 H 16 The ClN5]n test for 0.05% cobalt alloy steel achieves repeatability of test results in the shortest time compared to the 5-Cl-PADAB test under the same conditions. Furthermore, tests using other cobalt-containing liquids also show that [C]n is applicable. 16 H 16 ClN5]n replaces 5-Cl-PADAB, but uses [C]n from this application. 16 H 16 ClN5]n was prepared as an aqueous solution of less than 30% by mass and filtered through filter paper with a pore size of less than 5 micrometers. All [C]n added 16 H 16 ClN5]n is retained on the filter paper, while under the same conditions, the 5-Cl-PADAB can all pass through filter paper with a pore size of less than 5 micrometers.

[0036] The following describes a polymer solid-state battery electrolyte of this application, wherein the polymer solid-state battery electrolyte comprises one or more groups, including alcohol groups, hydroxyl groups, amine groups, halogen groups, sulfonic acid groups, acyl groups, rare hydrocarbon materials, or carboxyl groups.

[0037] In one embodiment of this application, the rare hydrocarbon material, containing amine groups, halogenated groups, and carboxyl groups comprises a chemical formula (C...13 H 14 Substances containing F3NO2)n or substances containing the following molecular structural formula I

[0038]

[0039] Contains (C) 13 H 14 The preparation method of substance F3NO2)n involves dissolving 15g of 1-(3,4-difluorophenyl)prop-2-en-1-amine and (E)-4-fluorobut-2-enoic acid in a molar ratio of 1:1 in 100g of aqueous solution, adding 0.5% ammonium sulfate and 0.5% ammonium bisulfite, heating the reaction at 30-60℃ for no less than 6 hours to form a viscous polymer, granulating, drying and grinding it into powder, denoted as powder A. Powder A contains a substance with the following molecular structural formula I.

[0040] A method for preparing a polymer solid-state battery electrolyte involves preparing a solution with a viscosity not exceeding 10 mPa·s using a certain amount of powder A with deionized water, preferably using a digital six-speed rotational viscometer to test the viscosity, adding lithium carbonate (A:lithium carbonate mass ratio of 30:1) according to a mass ratio, heating to 60 degrees Celsius and stirring until the pH of the solution no longer decreases, coating the solution with a plate and drying it, with a coating thickness not exceeding 1 cm, preferably 1 mm, and cutting it into 12 mm round pieces using a cutting machine, denoted as film a, i.e., film a belongs to a type of polymer solid-state battery electrolyte;

[0041] The membrane a remained at a constant weight after being dried in a constant temperature drying oven at 250 degrees Celsius for 48 hours, indicating that the membrane a has high thermal stability. The lithium carbonate is preferably lithium carbonate prepared in the lithium cobalt nickel recovery and extraction method in lithium batteries. In addition, the above 1-(3,4-difluorophenyl)prop-2-en-1-amine can be replaced by 2,2,2-trifluoroethyl acrylate, and the (E)-4-fluorobut-2-enoic acid can also be replaced by (E)-4,4,4-trifluorobut-2-enoic acid.

[0042] The infrared spectra of membrane a for the polymer solid-state battery electrolyte are as follows: Figure 2 ,Depend on Figure 2 As can be seen, characteristic absorptions of fluorine groups and phenyl groups appear at 2930, 2700, 1590, 1410, 1080, 790, and 770 cm⁻¹, an amine group appears at approximately 1500 cm⁻¹, a hydroxyl peak is at 1600 cm⁻¹, and no obvious olefin C=C stretching vibration is observed at 1640 cm⁻¹. Therefore, powder A contains a substance with the following molecular structure formula I.

[0043]

[0044] The above-described method for preparing a polymer solid-state battery electrolyte further includes, before the second step, a process of adding a compound solid-state electrolyte; after the second step, a process of combining membrane a with the surface of the compound solid-state electrolyte (in a non-gel state), wherein the combination of membrane a with the surface of the compound solid-state electrolyte constitutes a polymer solid-state electrolyte; membrane a or the combination of membrane a with the surface of the compound solid-state electrolyte also belongs to the matching composite in the above combination.

[0045] A certain amount of powder A is prepared into a solution with a viscosity not exceeding 10 mPa·s using deionized water. Lithium carbonate is added in a mass ratio of 30:1 (A:lithium carbonate mass ratio is 30:1). The solution is heated to 60 degrees Celsius and stirred until the pH of the solution no longer decreases. Then, Li7La3Zr2O is added in a mass ratio. 12 Or, after stirring LLZO powder to form a homogeneous gel (powder A: Li7La3Zr2O) 12 Or the mass ratio of LLZO powder is 1-4:5-6, Li7La3Zr2O 12 Alternatively, use LLZO powder (referred to as control powder, available on the market), coat it with a plate and dry it. The coating thickness should not exceed 1.3 mm, preferably 1 mm. Cut the film into 12 mm round pieces using a cutting machine. These are called control films. The control films contain Li7La3Zr2O. 12 Alternatively, LLZO powder compounds and polymer solid-state battery electrolyte powder A can be matched and compounded.

[0046] The following describes a solid-state battery compound solid electrolyte of this application. The compound has the general formula: AwBxCyDz, where A contains one or more of Li, Na, K, Ca, Mg, Fe, Cu, V, and Cr; B contains one or more of La, Sr, Y, Ba, Ga, Bi, Ce, Sm, Pr, Nd, Al, Ni, and Co; C contains one or more of Zr, Nb, Ti, Ta, Mo, Rh, Ir, Pt, Sb, Sc, Zn, Ru, W, Mn, Si, and P; and D contains one or more of F, Cl, Br, I, O, and S, where 1 ≤ w ≤8, 0≤x≤5, 0≤y≤4, 0≤z≤15, (when any of A, B, C, or D is composed of multiple elements, the corresponding w, x, y, and z quantities are the algebraic sum of the multiple constituent elements. Preferably, each element in A has a common valence range of 1 to 2.9; each element in B preferably has a common valence greater than 2; each element in C preferably has a common valence not less than 4; and each element in D preferably has a common valence not greater than -2). The solid-state electrolyte of this application, as a lithium-ion battery cell, has profound significance in the field of solid-state batteries.

[0047] The following describes a specific embodiment of a solid-state battery compound solid electrolyte.

[0048] The compound includes Li7La3Zr2O 12 LiNi 0.8 Co 0.1 Mn 0.1 O2, containing Li 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 One or more of the compounds.

[0049] One embodiment of a solid-state battery compound solid electrolyte, containing Li 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.9 5Si 0.05 O 11.99 F 0.02 Preparation of the compound: Li₂CO₃, K₂O, Na₂O, Al(OH)₃, La(NO₃)₃·6H₂O, Zr(NO₃)₄, and C₈H₂O were weighed according to the molar ratio of Li:Na:K:Al:La:Zr:Si:F of 70:0.8:4:0.4:30:19.5:0.5:0.22. 21 NSi (butyldimethyl(dimethylamino)silane), (C 13 H 14 Three moles of F3NO2)n were added sequentially to deionized water with stirring, and the pH was adjusted to 5-7 to form a solution. The solution was heated to 30-45°C, and then preferably ultrasonically stirred for 1-5 hours to form a gel. After granulation, the gel was dried at 100°C by forced air drying and pulverized into powder. The powder was placed in an alumina crucible and then placed in a muffle furnace. The temperature was increased to 1000-1200°C at a rate of 2°C / min, held for 1-6 hours, and then cooled with the furnace. The sintered powder was placed in a ball mill jar, isoacetone was added, and the mixture was ball-milled at 600 r / min for 10 hours. The resulting powder (preferably about 300 mesh) was designated as powder B. This powder was then vacuum-dried in a vacuum drying oven for 6 hours to form a pre-use powder, which was stored in a desiccator. Additionally, the Li2CO3 preferred in the lithium battery includes lithium carbonate prepared using a lithium cobalt-nickel recovery and extraction method, which also provides suitable raw materials for the preparation of compound solid electrolytes.

[0050] Li 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si0.05 O 11.99 F 0.02 The preparation of the compound described in (C) 13 H 14 F3NO2)n is powder A, using non-lithium-containing (C) 13 H 14 F3NO2)n participates in the reaction to prevent (C) 13 H 14 The hydroxyl and amino groups in F3NO2)n affect the lithium content or structural design of the compound through lithium complexation and adsorption; furthermore, the (C 13 H 14 F3NO2)n or powder A has a branched network structure Li 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 The role of compounds.

[0051] The preparation method of membrane b or a composite solid-state battery electrolyte is as follows:

[0052] A certain amount of powder A was prepared into a solution with a viscosity not exceeding 10 mPa·s using deionized water. Lithium carbonate was added at a mass ratio of 30:1 (A:lithium carbonate = 30:1; using lithium-containing powder A is beneficial for lithium contact sites and lithium migration). The solution was heated to 60 degrees Celsius and stirred until the pH of the solution no longer decreased. Then, powder B was added at a mass ratio of 1-4:5-6 and stirred to form a homogeneous gel. The gel was then coated onto a plate and dried. The coating thickness was not more than 1.3 mm, preferably 1 mm. The coating was then cut into 12 mm round pieces, denoted as film b. Film b simultaneously achieved the branched network structure containing Li. 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 Compound powder B and polymer solid-state battery electrolyte powder A are matched and composited. Membrane b is another matched composite in the above combination, and membrane b is also a composite solid electrolyte.

[0053] The following are the parameter performance tests conducted on compound solid electrolyte powder B and composite solid electrolyte membrane b. Figure 3 Electron micrographs of compound solid electrolyte powder B and composite solid electrolyte membrane b. Figure 3 Image (B) is an electron micrograph of solid electrolyte powder B. Figure 3In (B), a branched mesh-like pattern can be seen (the arrow indicates the presence of a mesh and short line imprints). Figure 3 Image (b) is an electron microscope image of the composite solid electrolyte membrane. In image (b), we can see that the fragments, which resemble a branched network, are covered with intersecting polymer lines. This indicates that the combination of polymer and compound (the circle indicates the micron shadow of the polymer electron microscope image / the arrow indicates the micron shadow of the branched network fragments) is a polymer solid-state battery electrolyte part. The compound is shaped into a branched network and then matched with the polymer solid-state battery electrolyte.

[0054] Elemental analysis of powder B material was performed using ICP combined with XPS, and the concentration data of each element were processed by software to obtain the percentage of each element as shown in Table 1 below.

[0055] Table 1

[0056] element Li Na K Al La Zr Si O F ％ 26.3 0.33 1.67 0.16 12.53 8.14 0.20 50.10 0.083

[0057] Figure 4 The image shows the XRD pattern of compound solid electrolyte powder B. Figure 4 In the middle, powder B and Li7La3Zr2O 12 The standard card (PDF#40-0894 or PDF#45-0109) is a perfect match. Further analysis suggests the following: potassium-containing cubic crystals are found at approximately 19°, 31°, and 38° of 2θ; sodium-containing cubic crystals are found at approximately 33.48° and 43.29° of 2θ; aluminum-containing cubic crystals are found at 38.4° and 44.5° of 2θ; silicon-containing crystals are found at 21° and 27.5° of 2θ; and fluorine-containing crystals are found at approximately 10.9°, 18.8°, and 24.9° of 2θ. Combined with ICP elemental analysis of powder B, powder B is considered to be modified and doped with Na, K, Al, Si, O, and F, resulting in Li7La3Zr2O. 12 The complex compound or electrolyte formed by crystal formation is denoted as Li. 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 Compounds.

[0058] Furthermore, this test also provides a method for preparing a film by forming electrolyte discs for relevant performance testing. Powder B is selected as the implementation method: 0.1g of powder B (pre-used powder) is weighed and placed in a stainless steel mold (12mm in diameter), and pressed for 3 minutes under a pressure of 10-200MPa, with a thickness not exceeding 1cm or mm, forming a pre-pressed disc, which is denoted as disc b. If the measurement meets the requirements, it indicates that the compound solid electrolyte disc b is easy to prepare a suitable film. After surface treatment, it is placed in a vacuum drying oven for storage.

[0059] Li7La3Zr2O purchased from the current market 12 Alternatively, LLZO powder (referred to as control powder) can be used to prepare round discs using the above preparation steps, which are referred to as control discs.

[0060] Furthermore, the combination or the matching composite in the combination can also press the membrane a onto both sides of the disc b to form a membrane ab, or press the membrane a onto both sides of a contrast disc to form a contrast membrane ab. This combination also belongs to the process of combining membrane a with the surface of the compound solid electrolyte.

[0061] The above membranes a, b, control membrane, disc b, control disc, membrane ab, and control membrane ab were placed flat between two stainless steel sheets with a diameter of 12 mm to form a stainless steel / electrolyte / stainless steel battery. Chemical testing was conducted using an analyzer and chemical workstation with AC impedance spectroscopy to test parameters such as the ionic conductivity and electrochemical window of the electrolyte (4.43). The battery temperature was controlled at room temperature or stabilized using a constant temperature oven. The test results are shown in Table 2 below.

[0062] Table 2

[0063] name electrical conductivity Electrochemical window V Membrane a 3.8 × 10⁻⁴ S·cm⁻¹ 4.4 membrane b 9.5 × 10⁻⁴ S·cm⁻¹ 5.3 Contrast membrane 6.4 × 10⁻⁴ S·cm⁻¹ 5.2 disc b 5.5 × 10⁻⁴ S.cm⁻¹ 5.5 Comparison of round pieces 3.7 × 10⁻⁴ S·cm⁻¹ 5.3 membrane ab 7.3 × 10⁻⁴ S·cm⁻¹ 5.2 Comparison of membranes ab 6.9 × 10⁻⁴ S·cm⁻¹ 4.5

[0064] Impedance spectroscopy tests were performed on disc b, a control disc made from compound solid electrolyte powder B, at room temperature. Figure 5 Impedance spectroscopy results of disc b (prepared from compound solid electrolyte powder B) and a control disc at room temperature are shown in the figure. Figure 5 As shown, compared to the control disc, the compound solid electrolyte disc b has higher conductivity. Furthermore, the small arcs appearing on the compound solid electrolyte disc b reflect the presence of Li... 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 The compound material has good ion diffusion and migration capabilities, and at least the modification and doping of Na, K, Al, Si, O and F have certain beneficial effects on the material.

[0065] As shown in Table 2, membrane a has good ionic conductivity, indicating that the amino, fluoride, carboxyl, hydroxyl, and polyfluoride groups arranged sequentially around the material containing structural formula I promote the exchange and transport of lithium ions. The high conductivity of membrane a reflects its good ion diffusion and migration capabilities, and the presence of structural formula I gives membrane a high electrochemical window.

[0066] Based on the above performance test results, the analysis shows that the combination includes the matching and composite of compound and polymer solid-state battery electrolyte, and the matching and composite of polymer solid-state battery electrolyte after the compound is branched into a network shape. Specifically, the matching and composite includes the branched network containing Li 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 Compound powder and polymer solid-state battery electrolyte powder are matched and composited to form a film, that is, for Li-containing... 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 The compatibility and principle analysis of compound powder and polymer solid-state battery electrolyte powder containing material of structural formula I are as follows:

[0067] Membrane b is composed of Li 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 The conductivity of the compound powder and the polymer solid-state battery electrolyte powder containing the substance of structural formula I, when combined, is higher than the sum of the conductivity of membrane a and wafer b, indicating that the Li-containing... 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 The compound powder and the polymer solid-state battery electrolyte powder containing the substance of structural formula I exhibit a synergistic gain effect in conductivity, and this effect is significantly better than that of the comparative film. The comparative film uses a matched composite of film a and a comparative disc, and the result is that the comparative film does not show a conductivity higher than the sum of the two, and no synergistic gain effect is observed. Combined with electron microscopy... Figure 3 It is known that the polymer solid-state battery electrolyte is made by shaping a branched network of compounds and then matching and compositing them. Analysis suggests that the polymer solid-state battery electrolyte contains substances with structural formula I, which will incorporate Li... 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F0.02 When a compound is branched into a network structure similar to that of its structural formula I, and then combined with a polymer solid-state battery electrolyte containing structural formula I, the two are at least similar in spatial structure. Furthermore, analysis suggests that the substances of structural formula I possess amine groups, fluoride ions, carboxyl groups, etc., around their spatial periphery, which are beneficial to Li. 6.4 Na 0.08 K 0.4 Al 0.0 4La3Zr 1.95 Si 0.05 O 11.99 F 0.02 The spatial structure of the compound and the interaction or combination of its lithium make it easier for the two to be matched into a composite combination, thus resulting in a synergistic gain effect in the conductivity results.

[0068] The following is an analysis of the beneficial effects of membrane a in improving the interface between the electrode and the solid electrolyte, or the combination of membrane a and the compound solid electrolyte interface:

[0069] A 50g stainless steel cylinder with a contact surface diameter of 5mm was horizontally pressed sequentially onto membrane a, membrane b, the control membrane, disc b, and the control disc. The depths to which the stainless steel cylinder penetrated and integrated into the membranes and discs were measured to be 0.6mm, 0.3mm, 0.2mm, 0.1mm, and 0.03mm, respectively. This indicates that the interfacial integration or containment of the membranes and discs decreases sequentially, with all membranes exhibiting better integration or containment than the disc. Furthermore, the conductivity of all membranes was 10-1. Within the range of -4, and considering the conductivity test results in Table 1, it can be seen that the interfacial contact depth or area of ​​the comparative membrane, membrane b, and membrane a increases sequentially, while the impedance decreases. Analysis suggests that the compatibility between the solid electrolyte and electrode of the comparative membrane, membrane b, and membrane a is better than that of the disc. The compound solid electrolyte disc b has a soft branched network structure. The 0.1 mm indentation depth of disc b is attributed to the elastic contraction of its branched network structure. Therefore, membranes a, b, and the comparative membrane can improve the compatibility between the solid electrolyte and the electrode and alleviate interfacial contact problems. Membranes a and b, and the comparative membrane a, are combinations of membrane a and the surface of the compound solid electrolyte, respectively. The conductivity test results combined with electron microscopy... Figure 3The surface structure shows that membrane a improves the contact or compatibility between the electrode and the solid electrolyte. The above process also includes a method for testing the compatibility and / or interface contact performance of the electrolyte and the electrode using membrane a. The membrane testing method for the compatibility and / or interface contact of the electrolyte and the electrode in this application is efficient, fast, and easy to operate. It can also be used in solid-state battery assembly. The solid-state battery in this application includes at least one combination of polymer solid-state battery electrolyte or solid-state battery compound solid-state electrolyte. For example, membrane a and the electrode are used to form a polymer solid-state battery, or membrane a, disc b and the electrode are used to form a composite or compound solid-state battery, or membrane b and the electrode are used to form a compound or composite solid-state battery.

[0070] Chemical testing was conducted on stainless steel / electrolyte / stainless steel batteries constructed using membrane a, membrane b, control membrane, disc b, membrane ab, and control membrane ab as electrolytes. After 400 cycles, the batteries still exhibited a discharge capacity of 130 mAh g⁻¹, and the average coulombic efficiency was higher than 99%. The aforementioned membranes and discs demonstrated high cycle stability.

[0071] Li 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 The presence of silicon in the compound is beneficial for structural stability and long-term cycling; F is beneficial for increased surface properties and ionic activity, which is beneficial for electrical conductivity; and the combination of Na, K, Al, and Si, including their large and small radii, is beneficial for lithium-ion migration, causing the compound to exhibit higher electrical conductivity than the test values ​​mentioned above.

Claims

1. A method for preparing a solid electrolyte, characterized in that: According to the molar ratio of Li:Na:K:Al:La:Zr:Si:F of 70:0.8:4:0.4:30:19.5:0.5:0.22, weigh out Li₂CO₃, K₂O, Na₂O, Al(OH)₃, La(NO₃)₃·6H₂O, Zr(NO₃)₄, C₈H₂O, and F. 21 NSi, (C 13 H 14 F3NO2)n was added sequentially with stirring to deionized water, the pH was adjusted to 5-7 to form a solution, heated and stirred to form a gel, dried and pulverized into powder, and then the powder was sintered at 1000-1200℃ to obtain Li. 6.4 Na 0.0 8K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 Solid electrolyte.

2. The method for preparing a solid electrolyte as described in claim 1, characterized in that: The Li2CO3 was prepared using a method that included the recovery and extraction of lithium, cobalt, and nickel.

3. The method for preparing a solid electrolyte as described in claim 1, characterized in that: The (C) 13 H 14 The preparation method of substance F3NO2)n involves preparing it by mixing 1-(3,4-difluorophenyl)prop-2-en-1-amine with (E)-4-fluorobut-2-enoic acid in a molar ratio of 1:

1.

4. A solid electrolyte, characterized in that: Including preparations made using any one of claims 1-3.

5. A composite solid electrolyte, characterized in that: It comprises a combination of the solid electrolyte obtained by claim 4 and a polymer solid electrolyte, wherein the polymer solid electrolyte is a substance with the following molecular structural formula I.

6. A method for preparing a composite solid electrolyte, characterized in that: A certain amount (C) 13 H 14 F3NO2)n was prepared into a solution with deionized water, and lithium carbonate was added according to the mass ratio. The solution was heated until the pH no longer decreased, and then Li2O3 prepared by the method of claim 1 was added according to the mass ratio. 6.4 Na 0.08 K 0.4 Al 0.04 La3Zr 1.95 Si 0.05 O 11.99 F 0.02 The mixture is stirred to form a homogeneous gel, then coated and dried to obtain the final product.

7. A solid-state battery, characterized in that: The electrolyte is composed of a solid electrolyte prepared using any one of the methods described in claims 1-3, or the electrolyte described in claim 4, or the electrolyte prepared using a method for preparing a composite solid electrolyte as described in claim 6.

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