A full solid-state lithium ion battery containing a halide-oxide composite solid-state electrolyte

Abstract

The application discloses a full solid-state lithium ion battery containing a halide oxide composite solid electrolyte. The halide oxide composite solid electrolyte promotes the amorphization of the zirconium-based halide oxide by introducing a lithium salt containing a phosphate radical into the zirconium-based halide oxide, effectively improves the lithium ion transmission rate and ionic conductivity, has good variability and excellent high-voltage stability. The full solid-state battery comprises a composite solid electrolyte sheet, a composite positive electrode sheet and a composite negative electrode sheet. The composite positive electrode sheet comprises a binder composed of the polymerization of (E)-4-methoxybut-2-ene acid and (2-acrylamidoethyl) tert-butyl carbamate, which can improve the interface bonding force of the composite positive electrode sheet, and improve the peeling force and ionic conductivity. The preparation process of the application is simple, the raw material cost is low, and the application has the potential for large-scale production.

Description

Technical Field

[0001] The present invention belongs to the technical field of batteries, and in particular relates to an all-solid-state lithium-ion battery containing a halide oxide composite solid electrolyte. Background Art

[0002] Lithium-ion batteries, with their high energy density, lightweight design, and long lifespan, have been widely used in various fields, including mobile electronic devices, electric vehicles, and aerospace. However, current commercial liquid lithium-ion batteries also present a series of problems, including high-temperature decomposition of the electrolyte, gas production, and lithium dendrites piercing the separator. Furthermore, the flammable and explosive nature of organic electrolytes poses serious safety risks.

[0003] In recent years, all-solid-state lithium batteries using inorganic solid electrolytes have attracted widespread attention due to their high energy density and high safety. Among various inorganic solid electrolytes, halide-based solid electrolytes, especially chloride solid electrolytes, stand out due to their high ionic conductivity, high mechanical compliance and wide electrochemical window. Despite these advantages, achieving high performance and low cost of halide solid electrolytes remains a huge challenge. Many halide solid electrolytes with high ionic conductivity rely on expensive metal components such as Ta, La, In, etc., which limits their practicality. In contrast, zirconium-based halides have significant cost advantages due to the high abundance of Zr elements in the earth's crust. However, their relatively low ionic conductivity limits their widespread application in high-performance all-solid-state batteries.

[0004] Therefore, it is of great significance to use cheap raw materials and simple methods to prepare halide-based solid electrolytes and all-solid-state lithium-ion batteries with high room-temperature ionic conductivity and relative stability to high-potential positive electrodes. Summary of the Invention

[0005] The object of the present invention is to provide an all-solid-state lithium-ion battery containing a halide oxide composite solid electrolyte with a high lithium ion transmission rate.

[0006] The technical solutions adopted by the present invention to achieve the above-mentioned purpose are:

[0007] An all-solid-state lithium-ion battery comprises a composite solid electrolyte, a composite positive electrode sheet and a composite negative electrode sheet, wherein the composite solid electrolyte comprises an amorphous phase component and a crystalline phase component.

[0008] Preferably, the amorphous phase component includes zirconium-based oxyhalide.

[0009] Preferably, the crystalline phase component comprises a lithium phosphate-containing salt.

[0010] Preferably, the composite solid electrolyte is expressed as xA-Li 2+2y ZrCl4O1+y wherein 0≤x≤0.3, 0≤y≤1, A is a lithium salt containing phosphate.

[0011] Preferably, the lithium salt containing phosphate comprises Li 1.3 Al 0.3 Ti 1.7 (PO4)3, Li 1.5 Al 0.5 Ge 1.5 at least one of (PO4)3and Li3PO4.

[0012] Preferably, the zirconium oxyhalide comprises a zirconium source compound, a lithium source compound, and an oxygen source compound.

[0013] Preferably, the zirconium source compound comprises ZrCl4.

[0014] Preferably, the lithium source compound comprises at least one of LiCl, Li2O, and Li2CO3.

[0015] Preferably, the oxygen source compound comprises at least one of Li2O, Li2CO3, and LiOH.

[0016] Preferably, the composite cathode sheet comprises a composite solid electrolyte and a binder.

[0017] Preferably, the polymeric monomers of the binder comprise (E)-4-methoxybut-2-enoic acid and tert-butyl (2-acrylamidoethyl)carbamate.

[0018] Preferably, the mass ratio of tert-butyl (2-acrylamidoethyl)carbamate to (E)-4-methoxybut-2-enoic acid is 10-100:15-150.

[0019] (E)-4-methoxybut-2-enoic acid and tert-butyl (2-acrylamidoethyl)carbamate as polymeric monomers of the binder form a network structure through synergistic polymerization, and their flexible polymer skeleton and groups such as methoxy, amide, and tert-butyl groups jointly play a role, on the one hand, to improve the cohesive force of the binder through hydrogen bonding and to enhance the interfacial adhesion; on the other hand, to form a lithiumophilic site to promote the transmission of lithium ions in the binder network and to optimize the compatibility of the electrode and electrolyte interface, thereby synergistically improving the peeling strength and ion conduction efficiency of the composite cathode sheet.

[0020] Preferably, the anode sheet comprises a sulfide solid electrolyte.

[0021] Preferably, the sulfide solid electrolyte comprises Li6PS5Cl.

[0022] More preferably, the polymerization monomer of the binder comprises allyl 2,2,3,3,3-pentafluoropropyl ether, and the mass ratio of allyl 2,2,3,3,3-pentafluoropropyl ether to (E)-4-methoxybut-2-enoic acid is 10-100:15-150. Allyl 2,2,3,3,3-pentafluoropropyl ether and (2-acrylamidoethyl) tert-butyl carbamate participate in the polymerization reaction together and play a synergistic role; the three-dimensional skeleton structure of the binder network is strengthened by cross-linking, and the cohesion and mechanical toughness of the polymer matrix are improved, thereby significantly enhancing the peeling strength of the composite cathode sheet; the strong electron-withdrawing effect of fluorine atoms reduces the surface energy of the binder to improve the wettability with the electrode material, construct an ion transmission channel, and improve the ionic conductivity of the all-solid-state battery.

[0023] The application also provides a preparation method of the composite solid-state electrolyte, comprising:

[0024] Preparation of the composite solid-state electrolyte: under the protection of argon, a lithium phosphate salt, a zirconium source compound, a lithium source compound, and an oxygen source compound are uniformly mixed, zirconia balls are added, and ball milling is performed at a speed of 550-700 rpm for 19-30 h to obtain the composite solid-state electrolyte.

[0025] Preferably, the lithium phosphate salt comprises Li 1.3 Al 0.3 Ti 1.7 (PO4)3, Li 1.5 Al 0.5 Ge 1.5 (PO4)3, and Li3PO4.

[0026] Preferably, the zirconium source compound comprises ZrCl4.

[0027] Preferably, the lithium source compound comprises at least one of LiCl, Li2O, and Li2CO3.

[0028] Preferably, the oxygen source compound comprises at least one of Li2O, Li2CO3, and LiOH.

[0029] Preferably, the molar ratio of the lithium phosphate salt to the zirconium source compound is 0.1-2:2-40.

[0030] Preferably, the molar ratio of the lithium source compound to the zirconium source compound is 6.5-65:5-50.

[0031] Preferably, the molar ratio of the oxygen source compound to the zirconium source compound is 6.5-65:5-50.

[0032] Preferably, the particle size of the zirconia balls is 5-15 mm.

[0033] Preferably, the mass molar ratio of the zirconium oxide balls to the zirconium source compound is 7-70 g:5-50 mmol.

[0034] The application also provides a preparation method of the binder, comprising:

[0035] Preparation of the binder: dissolve ammonium persulfate in deionized water to obtain an ammonium persulfate solution; add (E)-4-methoxybut-2-enoic acid, tert-butyl (2-acrylamidoethyl) carbamate, sodium dodecyl sulfate and OP-10 emulsifier in deionized water, perform ultrasonic emulsification, add the ammonium persulfate solution at 70-80°C, and react for 10-15 h under a nitrogen atmosphere to obtain the binder.

[0036] Preferably, the mass ratio of ammonium persulfate to deionized water in the ammonium persulfate solution is 6-60:150-1500.

[0037] Preferably, the mass ratio of (E)-4-methoxybut-2-enoic acid to deionized water is 15-150:225-2250.

[0038] Preferably, the mass ratio of tert-butyl (2-acrylamidoethyl) carbamate to (E)-4-methoxybut-2-enoic acid is 10-100:15-150.

[0039] Preferably, the mass ratio of sodium dodecyl sulfate to (E)-4-methoxybut-2-enoic acid is 0.75-7.5:15-150.

[0040] Preferably, the mass ratio of OP-10 emulsifier to sodium dodecyl sulfate is 0.3-4:0.75-7.5.

[0041] Preferably, the mass of the ammonium persulfate solution is measured by the mass of ammonium persulfate therein, and the mass ratio of ammonium persulfate to (E)-4-methoxybut-2-enoic acid is 6-60:15-150.

[0042] More preferably, the preparation of the binder can further add allyl 2,2,3,3,3-pentafluoropropyl ether.

[0043] More preferably, the mass ratio of allyl 2,2,3,3,3-pentafluoropropyl ether to (E)-4-methoxybut-2-enoic acid is 10-100:15-150.

[0044] The application also provides a preparation method of a composite positive electrode sheet, comprising:

[0045] Preparation of the composite positive electrode sheet: uniformly mix the positive electrode active material, the conductive agent and the composite solid-state electrolyte, ball mill at a rotation speed of 80-120 rpm for 0.5-1.5 h, and press into a sheet under a pressure of 250-350 MPa to obtain the composite positive electrode sheet.

[0046] Preferably, the positive active material comprises LiNi 0.83 Co 0.12 Mn 0.05 O2.

[0047] Preferably, the conductive agent comprises conductive carbon.

[0048] Preferably, the mass ratio of the positive active material to the conductive agent is 35-350:0.5-5.

[0049] Preferably, the mass ratio of the composite solid-state electrolyte to the conductive agent is 15-150:0.5-5.

[0050] More preferably, a binder can also be added in the preparation of the composite positive electrode sheet.

[0051] More preferably, the mass ratio of the binder to the conductive agent is 2.5-25:0.5-5.

[0052] The application also provides a preparation method of a composite negative electrode sheet, comprising:

[0053] Preparation of the composite negative electrode sheet: composite sulfide solid-state electrolyte on the surface of the negative active material, and press into a sheet under a pressure of 300 MPa to obtain the composite negative electrode sheet.

[0054] Preferably, the negative active material comprises lithium-indium alloy.

[0055] Preferably, in the lithium-indium alloy, the proportion of lithium atoms is 1-30 at%.

[0056] Preferably, the sulfide solid-state electrolyte comprises Li6PS5Cl.

[0057] Preferably, the mass ratio of the negative active material to the sulfide solid-state electrolyte is 3.5-35:25-250.

[0058] The application also provides a preparation method of a full solid-state lithium battery, comprising:

[0059] Preparation of the full solid-state lithium battery: press the composite solid-state electrolyte into a sheet under a pressure of 250-350 MPa to obtain an electrolyte sheet, evenly spread the electrolyte sheet on the composite positive electrode sheet, coat Li6PS5Cl on the surface of the electrolyte sheet, spread the negative electrode sheet, and press under a pressure of 250-350 MPa for 2-4 min to obtain the full solid-state lithium battery.

[0060] Preferably, the mass ratio of the electrolyte sheet to the composite positive electrode sheet is 10-100:1-10.

[0061] Preferably, the mass ratio of Li6PS5Cl to the electrolyte sheet is 0.5-5:10-100.

[0062] Preferably, the mass ratio of the composite negative electrode sheet to the composite positive electrode sheet is 1-10:1-10.

[0063] The present invention utilizes a phosphate-containing lithium salt and a zirconium-based oxyhalide solid electrolyte, along with a binder formed by polymerization of (E)-4-methoxybut-2-enoic acid and tert-butyl (2-acrylamidoethyl)carbamate. This advantageously achieves the following benefits: achieving a highly amorphous zirconium-based oxyhalide matrix, optimizing interfacial compatibility between the electrode and electrolyte, improving the ionic conductivity of the all-solid-state lithium-ion battery, and reducing overall raw material costs. Therefore, the present invention provides an all-solid-state lithium-ion battery containing an oxyhalide composite solid electrolyte with a high lithium ion transport rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 Schematic diagram of a scanning electron microscope image of the composite solid electrolyte prepared in Example 1.

[0065] Figure 2 Schematic diagram of a scanning electron microscope image of the composite solid electrolyte prepared in Example 2.

[0066] Figure 3 Schematic diagram of the X-ray diffraction pattern of the composite solid electrolyte.

[0067] Figure 4 Schematic diagram of the AC impedance spectrum of an all-solid-state lithium-ion battery.

[0068] Figure 5 Schematic diagram of the rate performance of all-solid-state lithium-ion batteries.

[0069] Figure 6 Schematic diagram of the long-cycle performance of all-solid-state lithium-ion batteries at 30°C.

[0070] Figure 7 Schematic diagram of the long-cycle performance of all-solid-state lithium-ion batteries at a cutoff voltage of 4.5 V. DETAILED DESCRIPTION

[0071] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0072] The concepts involved in the present application will be described below in combination with the drawings. It should be noted that the following description of the various concepts is only intended to make the content of the present application easier to understand, and does not represent a limitation on the scope of protection of the present application; meanwhile, the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0073] Example 1:

[0074] Preparation of the composite solid electrolyte: Li 1.3 Al 0.3 Ti 1.7 PO4)3, ZrCl4 and Li2O were uniformly mixed, zirconia balls were added, and ball milling was performed at a speed of 600 rpm for 20 h to obtain the composite solid electrolyte. Li 1.3 Al 0.3 Ti 1.7 The molar ratio of Li2O to ZrCl4 was 13:10, and the mass molar ratio of the zirconia balls to ZrCl4 was 35 g:10 mmol.

[0075] Preparation of the composite positive electrode sheet: LiNi 0.83 Co 0.12 Mn 0.05 O2, conductive carbon and the composite solid electrolyte were uniformly mixed, zirconia balls were added, and ball milling was performed at a speed of 100 rpm for 1 h, and a sheet was prepared by pressing under a pressure of 300 MPa to obtain the composite positive electrode sheet. LiNi 0.83 Co 0.12 Mn 0.05 The mass ratio of LiNiO2 to conductive carbon was 70:1, the mass ratio of the composite solid electrolyte to conductive carbon was 30:1, the particle size of the zirconia balls was 10 mm, and the mass ratio of the zirconia balls to conductive carbon was 1000:1.

[0076] Preparation of the composite negative electrode sheet: Li6PS5Cl was compounded on the surface of a lithium-indium alloy, and a sheet was prepared by pressing under a pressure of 300 MPa to obtain the composite negative electrode sheet. In the lithium-indium alloy, the atomic percentage of lithium was 1.5 at%; the mass ratio of the lithium-indium alloy to Li6PS5Cl was 7:50.

[0077] Preparation of the all-solid-state lithium battery: the composite solid electrolyte was pressed into a sheet under a pressure of 300 MPa to obtain an electrolyte sheet, the electrolyte sheet was uniformly laid on a composite positive electrode sheet, a composite negative electrode sheet was laid thereon, and the Li6PS5Cl side of the composite negative electrode sheet was in contact with the electrolyte sheet side, and the composite negative electrode sheet was pressed under a pressure of 300 MPa for 3 min to obtain the all-solid-state lithium battery. The mass ratio of the electrolyte sheet to the composite positive electrode sheet was 70:7, and the mass ratio of the composite negative electrode sheet to the composite positive electrode sheet was 57:7.

[0078] Example 2: Compared with Example 1, the difference is only in the preparation of the composite solid electrolyte.

[0079] Preparation of the composite solid electrolyte: under the protection of argon, Li 1.3 Al 0.3 Ti 1.7 PO4)3, ZrCl4 and Li2O were uniformly mixed, and zirconium oxide balls were added, and ball milling was performed at a speed of 600 rpm for 20 h to obtain the composite solid electrolyte. Li 1.3 Al 0.3 Ti 1.7 The molar ratio of (PO4)3 to ZrCl4 was 1:10, the molar ratio of Li2O to ZrCl4 was 13:10, the particle size of the zirconium oxide balls was 10 mm, and the mass molar ratio of the zirconium oxide balls to ZrCl4 was 35 g:10 mmol.

[0080] Example 3: Compared with Example 1, the difference is only in the preparation of the composite solid electrolyte.

[0081] Preparation of the composite solid electrolyte: under the protection of argon, Li 1.3 Al 0.3 Ti 1.7 PO4)3, ZrCl4 and Li2O were uniformly mixed, and zirconium oxide balls were added, and ball milling was performed at a speed of 600 rpm for 20 h to obtain the composite solid electrolyte. Li 1.3 Al 0.3 Ti 1.7 The molar ratio of (PO4)3 to ZrCl4 was 1.5:10, the molar ratio of Li2O to ZrCl4 was 13:10, the particle size of the zirconium oxide balls was 10 mm, and the mass molar ratio of the zirconium oxide balls to ZrCl4 was 35 g:10 mmol.

[0082] Example 4: Compared with Example 1, the difference is only in the preparation of the composite solid electrolyte.

[0083] Preparation of the composite solid electrolyte: under the protection of argon, Li 1.3 Al 0.3 Ti 1.7Li3PO4, ZrCl4and Li2O were uniformly mixed, zirconium oxide balls were added, and ball milling was performed at a rotation speed of 600 rpm for 20 h to obtain a composite solid electrolyte. The molar ratio of Li3PO4to ZrCl4was 1 : 10, the molar ratio of Li2O to ZrCl4was 13: 10, the particle size of the zirconium oxide balls was 10 mm, and the mass molar ratio of the zirconium oxide balls to ZrCl4was 35 g: 10 mmol. 1.3 Al 0.3 Ti 1.7 The molar ratio of Li3PO4to ZrCl4was 1 : 10, the molar ratio of Li2O to ZrCl4was 13: 10, the particle size of the zirconium oxide balls was 10 mm, and the mass molar ratio of the zirconium oxide balls to ZrCl4was 35 g: 10 mmol.

[0084] Example 5: This example is compared with Example 1, and the only difference is the preparation of the composite solid electrolyte.

[0085] Preparation of the composite solid electrolyte: Li3PO4, ZrCl4and Li2O were uniformly mixed under argon protection, zirconium oxide balls were added, and ball milling was performed at a rotation speed of 600 rpm for 20 h to obtain a composite solid electrolyte. The molar ratio of Li3PO4to ZrCl4was 1 : 10, the molar ratio of Li2O to ZrCl4was 13: 10, the particle size of the zirconium oxide balls was 10 mm, and the mass molar ratio of the zirconium oxide balls to ZrCl4was 35 g: 10 mmol.

[0086] Example 6:

[0087] Preparation of the composite solid electrolyte: Li 1.3 Al 0.3 Ti 1.7 Li3PO4, ZrCl4and Li2O were uniformly mixed, zirconium oxide balls were added, and ball milling was performed at a rotation speed of 600 rpm for 20 h to obtain a composite solid electrolyte. The molar ratio of Li3PO4to ZrCl4was 1 : 10, the molar ratio of Li2O to ZrCl4was 13: 10, the particle size of the zirconium oxide balls was 10 mm, and the mass molar ratio of the zirconium oxide balls to ZrCl4was 35 g: 10 mmol. 1.3 Al 0.3 Ti 1.7 The molar ratio of Li3PO4to ZrCl4was 1 : 10, the molar ratio of Li2O to ZrCl4was 13: 10, the particle size of the zirconium oxide balls was 10 mm, and the mass molar ratio of the zirconium oxide balls to ZrCl4was 35 g: 10 mmol.

[0088] Preparation of the binder: dissolve ammonium persulfate in deionized water to obtain an ammonium persulfate solution; add (E)-4-methoxybut-2-enoic acid, tert-butyl (2-acrylamidoethyl) carbamate, sodium dodecyl sulfate and OP-10 emulsifier in deionized water, ultrasonic emulsification, add the ammonium persulfate solution at 75℃, and react for 12h under a nitrogen atmosphere to obtain the binder. In the ammonium persulfate solution, the mass ratio of ammonium persulfate to deionized water is 12:300; the mass ratio of (E)-4-methoxybut-2-enoic acid to deionized water is 30:450, the mass ratio of tert-butyl (2-acrylamidoethyl) carbamate to (E)-4-methoxybut-2-enoic acid is 20:30, the mass ratio of sodium dodecyl sulfate to (E)-4-methoxybut-2-enoic acid is 1.5:30, and the mass ratio of OP-10 emulsifier to sodium dodecyl sulfate is 0.75:1.5; the mass of the ammonium persulfate solution is measured by the mass of ammonium persulfate therein, and the mass ratio of ammonium persulfate to (E)-4-methoxybut-2-enoic acid is 12:30.

[0089] Preparation of the composite positive electrode sheet: uniformly mix LiNi 0.83 Co 0.12 Mn 0.05 O2, conductive carbon, composite solid electrolyte and binder, ball mill at a speed of 100rpm for 1h, and press into a sheet under a pressure of 300MPa to obtain the composite positive electrode sheet. LiNi 0.83 Co 0.12 Mn 0.05 O2 and conductive carbon is 70:1, the mass ratio of composite solid electrolyte to conductive carbon is 30:1, and the mass ratio of binder to conductive carbon is 5:1.

[0090] Preparation of the composite negative electrode sheet: composite Li6PS5Cl on the surface of lithium-indium alloy, and press into a sheet under a pressure of 300MPa to obtain the composite negative electrode sheet. In the lithium-indium alloy, the atomic percentage of lithium is 1.5at%; the mass ratio of lithium-indium alloy to Li6PS5Cl is 7:50.

[0091] Preparation of the all-solid-state lithium battery: press the composite solid electrolyte into a sheet under a pressure of 300MPa to obtain an electrolyte sheet, uniformly lay the electrolyte sheet on the composite positive electrode sheet, lay the composite negative electrode sheet, and contact the Li6PS5Cl side of the composite negative electrode sheet with the electrolyte sheet side, and press under a pressure of 300MPa for 3min to obtain the all-solid-state lithium battery. The mass ratio of the electrolyte sheet to the composite positive electrode sheet is 70:7, and the mass ratio of the composite negative electrode sheet to the composite positive electrode sheet is 57:7.

[0092] Example 7: The difference between this example and Example 6 is only in the preparation of the binder.

[0093] Preparation of the adhesive: ammonium persulfate was dissolved in deionized water to obtain an ammonium persulfate solution; (E)-4-methoxybut-2-enoic acid, tert-butyl (2-acrylamidoethyl)carbamate, sodium dodecyl sulfate and OP-10 emulsifier were added in deionized water, ultrasonic emulsification was carried out, the ammonium persulfate solution was added at 75°C, and the reaction was carried out under a nitrogen atmosphere for 12h to obtain the adhesive. In the ammonium persulfate solution, the mass ratio of ammonium persulfate to deionized water was 12:300; the mass ratio of (E)-4-methoxybut-2-enoic acid to deionized water was 30:450, the mass ratio of tert-butyl (2-acrylamidoethyl)carbamate to (E)-4-methoxybut-2-enoic acid was 40:30, the mass ratio of sodium dodecyl sulfate to (E)-4-methoxybut-2-enoic acid was 1.5:30, and the mass ratio of OP-10 emulsifier to sodium dodecyl sulfate was 0.75:1.5; the mass of the ammonium persulfate solution was measured by the mass of ammonium persulfate therein, and the mass ratio of ammonium persulfate to (E)-4-methoxybut-2-enoic acid was 12:30.

[0094] Example 8: This example is compared with Example 6, and the only difference is the preparation of the adhesive.

[0095] Preparation of the adhesive: ammonium persulfate was dissolved in deionized water to obtain an ammonium persulfate solution; (E)-4-methoxybut-2-enoic acid, tert-butyl (2-acrylamidoethyl)carbamate, allyl 2,2,3,3,3-pentafluoropropyl ether, sodium dodecyl sulfate and OP-10 emulsifier were added in deionized water, ultrasonic emulsification was carried out, the ammonium persulfate solution was added at 75°C, and the reaction was carried out under a nitrogen atmosphere for 12h to obtain the adhesive. In the ammonium persulfate solution, the mass ratio of ammonium persulfate to deionized water was 12:300; the mass ratio of (E)-4-methoxybut-2-enoic acid to deionized water was 30:450, the mass ratio of tert-butyl (2-acrylamidoethyl)carbamate to (E)-4-methoxybut-2-enoic acid was 20:30, the mass ratio of allyl 2,2,3,3,3-pentafluoropropyl ether to (E)-4-methoxybut-2-enoic acid was 20:30, the mass ratio of sodium dodecyl sulfate to (E)-4-methoxybut-2-enoic acid was 1.5:30, and the mass ratio of OP-10 emulsifier to sodium dodecyl sulfate was 0.75:1.5; the mass of the ammonium persulfate solution was measured by the mass of ammonium persulfate therein, and the mass ratio of ammonium persulfate to (E)-4-methoxybut-2-enoic acid was 12:30.

[0096] Example 9: This example is compared with Example 6, and the only difference is the preparation of the adhesive.

[0097] Preparation of the binder: ammonium persulfate was dissolved in deionized water to obtain an ammonium persulfate solution; (E)-4-methoxybut-2-enoic acid, tert-butyl (2-acrylamidoethyl)carbamate, allyl 2,2,3,3,3-pentafluoropropyl ether, sodium dodecyl sulfate and OP-10 emulsifier were added in deionized water, ultrasonic emulsification was performed, the ammonium persulfate solution was added at 75°C, and the reaction was carried out under a nitrogen atmosphere for 12 h to obtain the binder. In the ammonium persulfate solution, the mass ratio of ammonium persulfate to deionized water was 12:300; the mass ratio of (E)-4-methoxybut-2-enoic acid to deionized water was 30:450, the mass ratio of tert-butyl (2-acrylamidoethyl)carbamate to (E)-4-methoxybut-2-enoic acid was 20:30, the mass ratio of allyl 2,2,3,3,3-pentafluoropropyl ether to (E)-4-methoxybut-2-enoic acid was 40:30, the mass ratio of sodium dodecyl sulfate to (E)-4-methoxybut-2-enoic acid was 1.5:30, and the mass ratio of OP-10 emulsifier to sodium dodecyl sulfate was 0.75:1.5; the mass of the ammonium persulfate solution was measured based on the mass of ammonium persulfate therein, and the mass ratio of ammonium persulfate to (E)-4-methoxybut-2-enoic acid was 12:30.

[0098] Comparative Example 1: This comparative example is compared with Example 1, and the only difference is the preparation of the composite solid electrolyte.

[0099] Preparation of the composite solid electrolyte: ZrCl4 and LiCl were uniformly mixed under argon protection, zirconia balls were added, and ball milling was performed at a rotation speed of 600 rpm for 20 h to obtain the composite solid electrolyte. The molar ratio of ZrCl4 to LiCl was 10:20, the particle size of the zirconia balls was 10 mm, and the mass molar ratio of the zirconia balls to ZrCl4 was 40 g:10 mmol.

[0100] Comparative Example 2: This comparative example is compared with Example 1, and the only difference is the preparation of the composite solid electrolyte.

[0101] Preparation of the composite solid electrolyte: ZrCl4 and LiCl were uniformly mixed under argon protection, zirconia balls were added, and ball milling was performed at a rotation speed of 600 rpm for 20 h to obtain the composite solid electrolyte. The molar ratio of ZrCl4 to LiCl was 10:15, the particle size of the zirconia balls was 10 mm, and the mass molar ratio of the zirconia balls to ZrCl4 was 40 g:10 mmol.

[0102] Comparative Example 3: This comparative example is compared with Example 6, and the only difference is that tert-butyl (2-acrylamidoethyl)carbamate is not used in the preparation of the binder.

[0103] Comparative Example 4: This comparative example is compared with Example 6, the only difference is that (E)-4-methoxybut-2-enoic acid is not used in the preparation of the binder.

[0104] Comparative Example 5: This comparative example is compared with Example 6, the only difference is that (2-acrylamidoethyl) tert-butyl carbamate and (E)-4-methoxybut-2-enoic acid are not used in the preparation of the binder.

[0105] Test Example 1: Microstructure characterization of the composite solid-state electrolyte.

[0106] Test sample: composite solid-state electrolyte prepared in Examples 1-2.

[0107] Test method: The surface of the composite solid-state electrolyte is treated by gold spraying, and the microstructure of the composite solid-state electrolyte is observed by scanning electron microscopy.

[0108] The scanning electron microscope image of the composite solid-state electrolyte prepared in Example 1 is shown in FIG. 1, and the scanning electron microscope image of the composite solid-state electrolyte prepared in Example 2 is shown in FIG. 2. Figure 1 Figure 2 The scanning electron microscope image of the composite solid-state electrolyte prepared in Example 1 is shown in FIG. 1, and the scanning electron microscope image of the composite solid-state electrolyte prepared in Example 2 is shown in FIG. 2.

[0109] Test Example 2: X-ray diffraction test of the composite solid-state electrolyte.

[0110] Test sample: composite solid-state electrolyte prepared in Examples 1-4 and Comparative Example 2.

[0111] Test method: The composite solid-state electrolyte is uniformly filled into the groove of the sample holder, and the sample is tightly attached to the sample holder by compaction. The scanning angle 2θ is set between 10°-90°, and the scanning speed is set between 0.02°-0.05° / s. X-ray diffraction test is performed, and the diffraction spectrum is collected.

[0112] The X-ray diffraction spectra of the composite solid-state electrolytes prepared in Examples 1-4 and Comparative Example 2 are shown in FIG. 3. Figure 3 1.3 As the amount of Li 0.3 Al 1.7 Ti 1.3 (PO4)3 increases, the peaks corresponding to ZrCl4 and Li2O in Examples 1-4 gradually weaken, and the characteristic peaks corresponding to Li 0.3 Al 1.7 Ti 1.3 (PO4)3 gradually increase, indicating that Li 0.3 ​​Ti 1.7 The addition of Li2O and (PO4)3 promotes the amorphization of the ZrCl4 and Li2O matrix.

[0113] Test Example 3: Peeling strength test of the composite cathode electrode sheet.

[0114] Test sample: composite cathode electrode sheet prepared in each example and comparative example.

[0115] Test method: the composite cathode electrode sheet is cut into a strip sample with a width of 15 mm and a length of 40 mm, a universal material testing machine is used, equipped with a 180° peeling clamp, the test speed is 15 mm / min, the electrode material surface is separated from the aluminum foil current collector, the material surface is fixed on the moving clamp, the aluminum foil is fixed on the static clamp, the maximum pulling force in the peeling process is recorded, and the average peeling force of the composite cathode electrode sheet is determined.

[0116] The peeling strength test results of the composite cathode electrode sheet are shown in Table 1:

[0117] Table 1: Peeling strength test results of the composite cathode electrode sheet

[0118]

[0119] Examples 1-4 show that by adjusting the amount of Li 1.3 Al 0.3 Ti 1.7 The amount of Li2O and (PO4)3 in the range shows that the effect of the amount of phosphoric acid lithium salt on the interface bonding force is relatively stable; Example 5 shows that by increasing the amount of Li2O and (PO4)3, the interface bonding force of the composite cathode electrode sheet is increased. 1.3 Al 0.3 Ti 1.7(PO4)3 is replaced by Li3PO4, and the peeling force is reduced compared with that of Example 1, indicating that there are differences in the compatibility of different lithium salt types with the system; Example 6 introduces a binder in the preparation of the composite positive electrode and optimizes the composition of the binder to improve the interaction between the components in the electrode, enhance the bonding strength of the electrode, and the peeling force is significantly improved compared with that of Example 1; Example 7 increases the amount of (2-acrylamidoethyl) tert-butyl carbamate, and the peeling force is further improved; Examples 8-9 introduce allyl 2,2,3,3,3-pentafluoropropyl ether and increase the ratio, which enhances the bonding network structure and achieves the highest peeling force; Comparative Example 1-2 did not use phosphate-containing lithium salts, and only ZrCl4 and LiCl were used to prepare the composite solid electrolyte. The peeling force was reduced compared with that of Example 1, confirming the importance of this component in maintaining the stability of the electrode structure; Comparative Example 3-4 lacked tert-butyl (2-acrylamidoethyl)carbamate or (E)-4-methoxybut-2-enoic acid in the binder, and the peeling force was reduced compared with that of Example 6; Comparative Example 5 lacked both tert-butyl (2-acrylamidoethyl)carbamate and (E)-4-methoxybut-2-enoic acid, and the peeling force was further reduced, indicating that the synergistic effect of the various components of the binder is indispensable for improving the interfacial bonding strength.

[0120] Test Example 4: Ionic conductivity test of all-solid-state lithium-ion battery.

[0121] Test samples: all-solid-state lithium-ion batteries prepared in various embodiments and comparative examples.

[0122] Test method: The ionic conductivity is measured by electrochemical impedance spectroscopy in air atmosphere, using Princeton PARSTAT MC electrochemical workstation connected to a computer, using the corresponding software for detection and data recording, the test frequency range is 1Hz-1000000Hz, and the disturbance voltage is 10mV. The ionic conductivity is calculated using the formula, where L is the electrolyte thickness, A is the surface area of ​​the stainless steel column, and R is the impedance value.

[0123] The AC impedance spectrum of the all-solid-state lithium-ion battery prepared by the present invention is as follows: Figure 4 As shown, the ionic conductivity test results of the all-solid-state lithium-ion battery prepared by the present invention are shown in Table 2.

[0124] Table 2 Ionic conductivity test of all-solid-state lithium-ion battery

[0125]

[0126] Example 1-2 By adjusting Li 1.3 Al 0.3 Ti 1.7The molar ratio of (PO4)3 to ZrCl4 indicates that the addition of lithium phosphate salts within this ratio range can promote the amorphization of zirconium-based oxyhalides, provide more continuous ion transport channels, and increase ion conductivity; Example 3-4 improves Li 1.3 Al 0.3 Ti 1.7 The amount of (PO4)3 used leads to an increase in the crystalline phase in the system, which reduces the ionic conductivity compared with Example 2. In Example 5, Li 1.3 Al 0.3 Ti 1.7 (PO4)3 is replaced by Li3PO4, which means that the composite system has a low degree of amorphization, or its interface compatibility with zirconium-based halide oxide is poor, resulting in increased ion transmission resistance; Example 6 introduces a binder in the preparation of the composite positive electrode sheet and optimizes the composition of the binder to improve the interface contact of the components inside the positive electrode sheet (active material, conductive carbon, composite solid electrolyte) and reduce the interface resistance of ion transmission; Example 7 increases the amount of (2-acrylamidoethyl) tert-butyl carbamate, and the ion conductivity is further improved; Examples 8-9 introduce the proportion of allyl 2,2,3,3,3-pentafluoropropyl ether, enhance the bonding network structure, improve the density of the electrode, promote the continuous transmission of ions in the electrode, improve the interface compatibility, and achieve the highest ion conductivity; Comparison In Example 1-2, no phosphate-containing lithium salt was used, and only ZrCl4 and LiCl were used to prepare a composite solid electrolyte. The ionic conductivity was lower than that in Example 1. Due to the lack of the promoting effect of the phosphate-containing lithium salt, the zirconium-based halide oxide was difficult to form an amorphous structure, the grain boundary resistance was large, and the ion transmission efficiency was low. In Comparative Example 3-4, the ionic conductivity was lower than that in Example 6 due to the lack of (2-acrylamidoethyl)carbamic acid tert-butyl ester or (E)-4-methoxybut-2-enoic acid in the binder. Comparative Example 5 lacked both (2-acrylamidoethyl)carbamic acid tert-butyl ester and (E)-4-methoxybut-2-enoic acid, resulting in a loose internal structure of the electrode, poor interface contact, and interrupted ion transmission path, thereby reducing the conductivity. The ionic conductivity was further reduced compared with Comparative Example 3.

[0127] Test Example 5: Battery cycle stability test of all-solid-state lithium-ion battery.

[0128] Test sample: the all-solid-state lithium-ion battery prepared in Example 2.

[0129] Test method: The long cycle performance of all-solid-state lithium-ion batteries is tested using the LAND battery test system.

[0130] The rate performance of the all-solid-state lithium-ion battery prepared in Example 2 is as follows: Figure 5As shown, high capacity can still be maintained at a high rate of 3C, proving that the high ionic conductivity of the composite solid electrolyte ensures ion transport inside the battery and achieves excellent high-rate performance.

[0131] The long cycle performance of the all-solid-state lithium-ion battery prepared in Example 2 at 30°C is as follows: Figure 6 As shown, the high capacity is maintained at a current of 1C, and the capacity retention rate after 700 cycles is 88.6%, thanks to Li 1.3 Al 0.3 Ti 1.7 (PO4)3 has excellent high-pressure stability.

[0132] The long cycle performance of the all-solid-state lithium-ion battery prepared in Example 2 at a cut-off voltage of 4.5V is as follows: Figure 7 As shown in the figure, the capacity retention rate is 80.4%, and the stable operation shows that the prepared composite solid electrolyte effectively improves the overall energy density of the battery.

[0133] The embodiments and / or implementation methods described above are only used to illustrate the preferred embodiments and / or implementation methods for realizing the technology of the present invention, and do not impose any form of limitation on the implementation methods of the technology of the present invention. Any person skilled in the art may make slight changes or modifications to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as technologies or embodiments that are essentially the same as the present invention.

[0134] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of this application, they can also make several improvements, modifications or changes, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. An all-solid-state lithium-ion battery, comprising a composite solid electrolyte, a composite positive electrode sheet, and a composite negative electrode sheet, wherein the composite solid electrolyte comprises an amorphous phase component and a crystalline phase component, the amorphous phase component comprises a zirconium-based oxyhalide, and the crystalline phase component comprises a phosphate-containing lithium salt; the composite positive electrode sheet comprises a composite solid electrolyte and a binder, wherein the polymerizable monomers of the binder comprise (E)-4-methoxybut-2-enoic acid and tert-butyl (2-acrylamidoethyl)carbamate.

2. The all-solid-state lithium-ion battery according to claim 1, characterized in that: The composite solid electrolyte is expressed as xA-Li 2+2y ZrCl4O 1+y , wherein 0<x≤0.3, 0≤y≤1, and A is a lithium salt containing phosphate.

3. The all-solid-state lithium-ion battery according to claim 1, characterized in that: The phosphate-containing lithium salt includes Li 1.3 Al 0.3 Ti 1.7 (PO4)3、Li 1.5 Al 0.5 Ge 1.5 At least one of (PO4)3 and Li3PO4.

4. The all-solid-state lithium-ion battery according to claim 1, characterized in that: The raw materials for preparing the zirconium-based oxyhalide include a zirconium source compound, a lithium source compound and an oxygen source compound, and the zirconium source compound includes ZrCl4.

5. The all-solid-state lithium-ion battery according to claim 4, characterized in that: The lithium source compound includes at least one of LiCl, Li2O and Li2CO3.

6. The all-solid-state lithium-ion battery according to claim 4, characterized in that: The oxygen source compound includes at least one of Li2O, Li2CO3 and LiOH.

7. The all-solid-state lithium-ion battery according to claim 1, characterized in that: The mass ratio of the tert-butyl (2-acrylamidoethyl)carbamate to the (E)-4-methoxybut-2-enoic acid is 10-100:15-150.

8. The all-solid-state lithium-ion battery according to claim 1, characterized in that: The negative electrode sheet includes a sulfide solid electrolyte, and the sulfide solid electrolyte includes Li6PS5Cl.

Images