Organic-inorganic composite solid-state battery electrolyte and preparation device

Abstract

The invention discloses an organic-inorganic composite solid-state battery electrolyte and a preparation device, and relates to the field of lithium batteries. The invention relates to an organic-inorganic composite solid-state battery electrolyte, which comprises an organic-inorganic composite solid-state battery electrolyte, the electrolyte is prepared by stirring and compounding an organic polymer matrix, an inorganic solid electrolyte material, an ionic liquid and an additive, the particle size and composition of the inorganic solid electrolyte material are optimized, the ionic conductivity is remarkably improved through the synergistic effect of the inorganic solid electrolyte material, the organic polymer matrix and the ionic liquid, and the electrolyte has good flexibility and strength due to the compounding of the organic polymer matrix and the inorganic material and the addition of the additive; the solid electrolyte can adapt to the volume change of the battery, the interface contact between the electrolyte and an electrode material is improved by selecting proper organic polymers and additives, the interface resistance is reduced, the growth of lithium dendrites is effectively inhibited, the solid electrolyte is non-flammable and non-volatile, and the safety of the battery is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium batteries, and in particular to an organic-inorganic composite solid-state battery electrolyte and a preparation device thereof. Background Art

[0002] With the continuous development of science and technology, future electric vehicles, smart grids and flexible wearable electronic devices require electrochemical energy storage devices with high energy density, long cycle life and high safety. Among them, lithium-ion batteries have been widely studied and applied since they were commercialized by Sony in the 1990s. After research and development, lithium-ion batteries based on graphite anodes and transition metal oxide cathodes have difficulty breaking through the energy density limit and are insufficient to provide long driving range for electric vehicles and power smart / multifunctional electronic products. Therefore, in recent years, some promising lithium batteries, such as lithium metal batteries with ultra-high theoretical energy density, have attracted increasing attention.

[0003] However, the organic electrolyte in lithium-ion batteries is flammable and explosive at high temperatures, posing a serious safety hazard. At the same time, since the metallic lithium negative electrode is very prone to producing lithium dendrites, they may pierce the diaphragm and cause a short circuit. Therefore, the development of new electrolytes that inhibit dendrite growth and are inherently safe is the key to promoting the development of high-energy-density lithium batteries. In view of this, the present invention is proposed. Summary of the Invention

[0004] The purpose of the present invention is to provide an organic-inorganic composite solid-state battery electrolyte and a preparation device. By optimizing the particle size and composition of the inorganic solid-state electrolyte material, and the synergistic effect with the organic polymer matrix and ionic liquid, the ionic conductivity of the electrolyte is significantly improved, which is beneficial to improving the charge and discharge performance of the battery, thereby solving the problems raised in the above-mentioned background technology.

[0005] To achieve the above-mentioned object, the present invention provides the following technical solutions: an organic-inorganic composite solid-state battery electrolyte, comprising an organic-inorganic composite solid-state battery electrolyte;

[0006] The organic polymer matrix, inorganic solid electrolyte material, ionic liquid and additives are mixed and compounded;

[0007] The organic polymer matrix is ​​a blend of polyethylene oxide and polyvinylidene fluoride-hexafluoropropylene, the inorganic solid electrolyte material is lithium lanthanum zirconium oxide, the ionic liquid is 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, and the additive is a mixture of vinylene carbonate and silicon dioxide.

[0008] Exemplarily, the organic polymer matrix accounts for 40%-60% of the total mass, and the mass ratio of polyethylene oxide to polyvinylidene fluoride-hexafluoropropylene is 2:1-3:1;

[0009] The inorganic solid electrolyte material accounts for 40%-60% of the total mass, and the particle size of the lithium lanthanum zirconium oxide is 10nm-100nm;

[0010] The ionic liquid accounts for 10%-20% of the total mass, the additive accounts for 5%-10% of the total mass, and the mass ratio of vinylene carbonate to silicon dioxide is 1:1-2:1.

[0011] A device for preparing an organic-inorganic composite solid-state battery electrolyte comprises a preparation tank, wherein two sides of the preparation tank are symmetrically connected to a first feeding hopper and a second feeding hopper, respectively; a discharge port is provided at the bottom of the preparation tank, and a solenoid valve is provided at the discharge port;

[0012] Also includes:

[0013] A first storage tank, a second storage tank, and a third storage tank are equidistantly arranged on the top of the preparation tank;

[0014] Connecting feeding pipes at the discharge ports of the first storage tank, the second storage tank, and the third storage tank, wherein the feeding pipes are located inside the preparation tank;

[0015] A metering pump provided between the discharge ports and the feeding pipes of the first, second and third storage tanks is used to accurately meter the materials;

[0016] a screen box fixedly connected to the interior of the preparation tank and located above the first and second feeding hoppers;

[0017] a stirring mechanism for stirring and mixing the electrolyte slurry, wherein the stirring mechanism is installed inside the preparation tank, and the screen box is connected to the stirring mechanism;

[0018] The toggle plates are equidistantly arranged inside the screen box, and the toggle plates rotate in a circle inside the screen box.

[0019] Exemplarily, the stirring mechanism includes a driving motor, a first rotating shaft, a stirring rod and a U-shaped scraper. A through opening is opened in the middle position of the screen box, the driving motor is bolted in the through opening of the screen box, the first rotating shaft key is connected to the output shaft at one end of the driving motor, the stirring rod is symmetrically fixedly connected to both sides of the first rotating shaft, the U-shaped scraper is fixedly connected to the outer side of the stirring rod, and the U-shaped scraper slides against the inner wall of the preparation tank.

[0020] Exemplarily, the drive motor is a dual-shaft motor, and the output shaft at the other end of the drive motor is keyed to a second rotating shaft, the top of the second rotating shaft is fixedly connected to a hemispherical mixing disk, the inner top of the preparation tank is fixedly connected to a fixing rod, the bottom end of the fixing rod is fixedly connected to an arc-shaped plate, the arc-shaped plate slides against the inner wall of the hemispherical mixing disk, the feeding port of the feeding pipe is located above the hemispherical mixing disk, and the toggle plate is fixedly connected to the hemispherical mixing disk by a connecting rod.

[0021] Exemplarily, a circle of inclined guide rings is fixedly connected to a position near the hemispherical mixing disk in the preparation tank, and the inclined guide rings are located on the outside of the hemispherical mixing disk.

[0022] Exemplarily, the interiors of the first storage tank, the second storage tank, and the third storage tank are all fixedly connected with inclined guide blocks, and the inclined guide blocks gradually tilt downward near the discharge ports of the first storage tank, the second storage tank, and the third storage tank.

[0023] Exemplarily, a transparent observation window is fixedly connected to the surface of the preparation tank, and the first storage tank, the second storage tank and the third storage tank are all transparent glass tanks.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The present invention significantly improves the ionic conductivity of the electrolyte by optimizing the particle size and composition of the inorganic solid electrolyte material, as well as the synergistic effect with the organic polymer matrix and ionic liquid, which is beneficial to improving the charge and discharge performance of the battery.

[0026] 2. The present invention provides the electrolyte with good flexibility and strength through the compounding of the organic polymer matrix and the inorganic material and the addition of additives, which can adapt to the volume change of the battery during use, improve the cycle life of the battery, and achieve good mechanical properties.

[0027] 3. The present invention improves the interface contact between the electrolyte and the electrode material by selecting appropriate organic polymers and additives, reduces the interface resistance, improves the overall performance of the battery, and achieves excellent interface compatibility.

[0028] 4. The present invention utilizes the solid electrolyte itself, which is non-flammable and non-volatile, has good interface stability and long cycle performance, and effectively inhibits the growth of lithium dendrites, greatly improving the safety of the battery and achieving good safety performance.

[0029] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the present invention;

[0031] Figure 2 It is a schematic diagram of the cross-sectional structure of the present invention;

[0032] Figure 3 It is a schematic diagram of the top view of the structure of the present invention;

[0033] Figure 4 This is a schematic structural diagram of the screen box of the present invention;

[0034] Figure 5 For the present invention Figure 2 A schematic diagram of the partially enlarged structure at center A;

[0035] Figure 6 For the present invention Figure 2 Schematic diagram of the locally enlarged structure at point B in the middle.

[0036] In the figure: 1. Preparation tank; 101. First feeding hopper; 102. Second feeding hopper; 103. Drive motor; 104. First rotating shaft; 105. Stirring rod; 106. U-shaped scraper; 107. First storage tank; 108. Second storage tank; 109. Third storage tank; 1010. Metering pump; 1011. Feeding pipe; 1012. Inclined guide block; 1013. Transparent observation window; 2. Screen box; 3. Second rotating shaft; 301. Hemispherical mixing disk; 302. Fixed rod; 303. Arc plate; 304. Connecting rod; 305. Toggle plate; 306. Inclined guide ring. DETAILED DESCRIPTION

[0037] 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.

[0038] The present invention provides an organic-inorganic composite solid-state battery electrolyte, comprising an organic-inorganic composite solid-state battery electrolyte;

[0039] It is made of organic polymer matrix, inorganic solid electrolyte material, ionic liquid and additives;

[0040] The organic polymer matrix is ​​a blend of polyethylene oxide and polyvinylidene fluoride-hexafluoropropylene, the inorganic solid electrolyte material is lithium lanthanum zirconium oxide, the ionic liquid is 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, and the additive is a mixture of vinylene carbonate and silicon dioxide.

[0041] Preferably, the organic polymer matrix accounts for 40%-60% of the total mass, and the mass ratio of polyethylene oxide to polyvinylidene fluoride-hexafluoropropylene is 2:1-3:1;

[0042] The inorganic solid electrolyte material accounts for 40%-60% of the total mass, and the particle size of lithium lanthanum zirconium oxide is 10nm-100nm;

[0043] The ionic liquid accounts for 10%-20% of the total mass, the additive accounts for 5%-10% of the total mass, and the mass ratio of vinylene carbonate to silicon dioxide is 1:1-2:1.

[0044] Example 1:

[0045] The organic polymer matrix accounts for 40% of the total mass, among which the mass ratio of polyethylene oxide to polyvinylidene fluoride-hexafluoropropylene is 3:1; the inorganic solid electrolyte material accounts for 40% of the total mass, among which the particle size of lithium lanthanum zirconium oxide is 10nm; the ionic liquid accounts for 10% of the total mass; the additives account for 5% of the total mass, among which the mass ratio of vinylene carbonate to silica is 2:1.

[0046] Example 2:

[0047] The organic polymer matrix accounts for 60% of the total mass, of which the mass ratio of polyethylene oxide to polyvinylidene fluoride-hexafluoropropylene is 2:1; the inorganic solid electrolyte material accounts for 60% of the total mass, of which the particle size of lithium lanthanum zirconium oxide is 100nm; the ionic liquid accounts for 20% of the total mass; the additives account for 10% of the total mass, of which the mass ratio of vinylene carbonate to silica is 1:1.

[0048] Example 3:

[0049] like Figure 1-6 As shown;

[0050] A device for preparing an organic-inorganic composite solid-state battery electrolyte comprises a preparation tank 1, with a first feeding hopper 101 and a second feeding hopper 102 symmetrically connected to the two sides of the preparation tank 1, and a discharge port is provided at the bottom of the preparation tank 1, and a solenoid valve is provided at the discharge port;

[0051] Also includes:

[0052] A first storage tank 107, a second storage tank 108 and a third storage tank 109 are equidistantly arranged on the top of the preparation tank 1;

[0053] Connect the feeding pipe 1011 at the outlet of the first storage tank 107, the second storage tank 108 and the third storage tank 109, and the feeding pipe 1011 is located inside the preparation tank 1;

[0054] The metering pump 1010 is provided between the discharge ports of the first storage tank 107, the second storage tank 108 and the third storage tank 109 and the feeding pipe 1011, and is used to accurately measure the materials;

[0055] The screen box 2 is fixedly connected to the inside of the preparation tank 1 and is located above the first feeding hopper 101 and the second feeding hopper 102;

[0056] A stirring mechanism for stirring and mixing the electrolyte slurry, the stirring mechanism is installed inside the preparation tank 1, and the screen box 2 is connected to the stirring mechanism;

[0057] The toggle plates 305 are equidistantly arranged inside the screen box 2 , and the toggle plates 305 rotate in a circle inside the screen box 2 .

[0058] Preferred;

[0059] like Figure 2 As shown, the stirring mechanism includes a driving motor 103, a first rotating shaft 104, a stirring rod 105 and a U-shaped scraper 106. A through opening is opened in the middle position of the screen box 2. The driving motor 103 is bolted into the through opening of the screen box 2. The first rotating shaft 104 is keyed to the output shaft at one end of the driving motor 103. The stirring rod 105 is symmetrically fixedly connected to both sides of the first rotating shaft 104. The U-shaped scraper 106 is fixedly connected to the outer side of the stirring rod 105. The U-shaped scraper 106 slides against the inner wall of the preparation tank 1.

[0060] After the preliminary processing of the various raw materials of the organic-inorganic composite solid-state battery electrolyte is completed, the staff can add the blend of polyethylene oxide and polyvinylidene fluoride-hexafluoropropylene, lithium lanthanum zirconium oxide, vinylene carbonate and silica into the first storage tank 107, the second storage tank 108 and the third storage tank 109 for temporary storage, and then the staff can add a certain amount of organic solvent acetonitrile into the preparation tank 1 through the first feeding hopper 101, and then the metering pump 1010 can be started to transport the blend of polyethylene oxide and polyvinylidene fluoride-hexafluoropropylene, lithium lanthanum zirconium oxide, vinylene carbonate and silica to the screen box 2 in the preparation tank 1 through the feeding pipe 1011 according to the specified mass ratio, and then the drive motor 103 can be started, so that the drive motor 103 drives the stirring rod 105 and the U-shaped scraper 106 to stir the organic solvent acetonitrile through the first rotating shaft 104, and then the toggle plate 305 can be controlled to rotate in the screen box 2;

[0061] At this time, the mixture of polyethylene oxide and polyvinylidene fluoride-hexafluoropropylene, lithium lanthanum zirconium oxide, vinylene carbonate and silicon dioxide will be uniformly and continuously scattered into the organic solvent acetonitrile through the mesh of the screen box 2 under the toggle of the toggle plate 305. After stirring for a period of time to fully mix the mixture of polyethylene oxide and polyvinylidene fluoride-hexafluoropropylene, lithium lanthanum zirconium oxide, vinylene carbonate and silicon dioxide with the organic solvent acetonitrile, 1-ethyl-3-methyl-1-nitropropene can be added through the second feeding hopper 102. A mixture of imidazole bis(trifluoromethanesulfonyl)imide salt, vinylene carbonate and silica is added to the preparation tank 1 in a mass ratio, and then stirred at 30°C-50°C for 3-5 hours to obtain an electrolyte mixed slurry. After stirring and preparation, the electromagnetic valve at the discharge port at the bottom of the preparation tank 1 can be opened to discharge the electrolyte mixed slurry and pour it into a mold. After drying in a vacuum drying oven at 50°C-70°C for 10-15 hours, demolding is performed to obtain an organic-inorganic composite solid-state battery electrolyte.

[0062] It is worth explaining;

[0063] The driving motor 103 is a dual-axis motor. The output shaft at the other end of the driving motor 103 is keyed to a second rotating shaft 3. The top of the second rotating shaft 3 is fixedly connected to a hemispherical mixing disk 301. The inner top of the preparation tank 1 is fixedly connected to a fixing rod 302. The bottom end of the fixing rod 302 is fixedly connected to an arc plate 303. The arc plate 303 slides against the inner wall of the hemispherical mixing disk 301. The feeding port of the feeding tube 1011 is located above the hemispherical mixing disk 301. The toggle plate 305 is fixedly connected to the hemispherical mixing disk 301 through a connecting rod 304.

[0064] When the materials in the first storage tank 107, the second storage tank 108 and the third storage tank 109 are sucked into the preparation tank 1 by the metering pump 1010, the materials will first fall onto the hemispherical mixing disk 301 under the guidance of the feeding pipe 1011, and then the drive motor 103 is started, and the drive motor 103 will drive the hemispherical mixing disk 301 to rotate relatively slowly through the second rotating shaft 3, and then the hemispherical mixing disk 301 will mix the various materials with the cooperation of the arc plate 303, so as to facilitate the pre-mixing of the materials, so that the materials can be scattered through the screen box 2 onto the organic solvent acetonitrile added in advance into the preparation tank 1;

[0065] It can not only promote the thoroughness of the stirring and mixing of the electrolyte slurry, but also further improve the preparation rate and save preparation time. When the materials are mixed, the hemispherical mixing disk 301 is quickly driven to rotate, and the mixed materials will be thrown out from the hemispherical mixing disk 301 under the action of centrifugal force, and then fall into the screen box 2.

[0066] A circle of inclined guide ring 306 is fixedly connected to a position near the hemispherical mixing disk 301 in the preparation tank 1 , and the inclined guide ring 306 is located outside the hemispherical mixing disk 301 .

[0067] By setting the inclined guide ring 306, when the premixed material is thrown out of the hemispherical mixing disk 301 under the action of centrifugal force, the inclined guide ring 306 can guide the mixed material so that the mixed material can fully fall into the screen box 2.

[0068] Furthermore, the interiors of the first storage tank 107 , the second storage tank 108 and the third storage tank 109 are all fixedly connected with inclined guide blocks 1012 , which gradually tilt downward near the discharge ports of the first storage tank 107 , the second storage tank 108 and the third storage tank 109 .

[0069] By setting the inclined guide block 1012, the materials in the first storage tank 107, the second storage tank 108 and the third storage tank 109 can be diverted so that the metering pump 1010 can fully extract the materials.

[0070] Finally, a transparent observation window 1013 is fixedly connected to the surface of the preparation tank 1, and the first storage tank 107, the second storage tank 108 and the third storage tank 109 are all transparent glass tanks.

[0071] By setting the transparent observation window 1013, when the electrolyte slurry is stirred and mixed, it is convenient for the staff to check the stirring and mixing of the electrolyte slurry through the transparent observation window 1013. By making the first storage tank 107, the second storage tank 108 and the third storage tank 109 all made of transparent glass jars, it is convenient to check the remaining materials in the first storage tank 107, the second storage tank 108 and the third storage tank 109 through the first storage tank 107, the second storage tank 108 and the third storage tank 109 so that timely addition can be made.

[0072] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. An organic-inorganic composite solid-state battery electrolyte, characterized in that: Including organic-inorganic composite solid-state battery electrolytes; The organic polymer matrix, inorganic solid electrolyte material, ionic liquid and additives are mixed and compounded; The organic polymer matrix is ​​a blend of polyethylene oxide and polyvinylidene fluoride-hexafluoropropylene, the inorganic solid electrolyte material is lithium lanthanum zirconium oxide, the ionic liquid is 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, and the additive is a mixture of vinylene carbonate and silicon dioxide.

2. The organic-inorganic composite solid-state battery electrolyte according to claim 1, characterized in that: The organic polymer matrix accounts for 40%-60% of the total mass, and the mass ratio of the polyethylene oxide to polyvinylidene fluoride-hexafluoropropylene is 2:1-3:1; The inorganic solid electrolyte material accounts for 40%-60% of the total mass, and the particle size of the lithium lanthanum zirconium oxide is 10nm-100nm; The ionic liquid accounts for 10%-20% of the total mass, the additive accounts for 5%-10% of the total mass, and the mass ratio of vinylene carbonate to silicon dioxide is 1:1-2:

1.

3. A device for preparing an organic-inorganic composite solid-state battery electrolyte according to any one of claims 1 to 2, characterized in that: It comprises a preparation tank (1), wherein two sides of the preparation tank (1) are symmetrically connected to a first feeding hopper (101) and a second feeding hopper (102), and a discharge port is provided at the bottom of the preparation tank (1), and a solenoid valve is provided at the discharge port; Also includes: A first material storage tank (107), a second material storage tank (108), and a third material storage tank (109) are equidistantly arranged at the top of the preparation tank (1); Connecting the feeding pipes (1011) at the outlets of the first storage tank (107), the second storage tank (108), and the third storage tank (109), wherein the feeding pipes (1011) are located inside the preparation tank (1); A metering pump (1010) provided between the discharge ports of the first storage tank (107), the second storage tank (108), and the third storage tank (109) and the feeding pipe (1011) for accurately metering the material; A screen box (2) fixedly connected to the interior of the preparation tank (1) and located above the first feeding hopper (101) and the second feeding hopper (102); A stirring mechanism for stirring and mixing the electrolyte slurry, wherein the stirring mechanism is installed inside the preparation tank (1), and the screen box (2) is connected to the stirring mechanism; The toggle plates (305) are equidistantly arranged inside the screen box (2), and the toggle plates (305) rotate in a circular shape inside the screen box (2).

4. The device for preparing an organic-inorganic composite solid-state battery electrolyte according to claim 3, characterized in that: The stirring mechanism includes a driving motor (103), a first rotating shaft (104), a stirring rod (105) and a U-shaped scraper (106); a through opening is opened in the middle position of the screen box (2); the driving motor (103) is bolted into the through opening of the screen box (2); the first rotating shaft (104) is key-connected to the output shaft at one end of the driving motor (103); the stirring rod (105) is symmetrically fixedly connected to both sides of the first rotating shaft (104); the U-shaped scraper (106) is fixedly connected to the outer side of the stirring rod (105); and the U-shaped scraper (106) is slidably attached to the inner wall of the preparation tank (1).

5. The device for preparing an organic-inorganic composite solid-state battery electrolyte according to claim 4, characterized in that: The driving motor (103) is a dual-shaft motor. The output shaft at the other end of the driving motor (103) is keyed to a second rotating shaft (3). The top end of the second rotating shaft (3) is fixedly connected to a hemispherical mixing disk (301). The top end of the interior of the preparation tank (1) is fixedly connected to a fixing rod (302). The bottom end of the fixing rod (302) is fixedly connected to an arc-shaped plate (303). The arc-shaped plate (303) is slidably attached to the inner wall of the hemispherical mixing disk (301). The feeding port of the feeding pipe (1011) is located above the hemispherical mixing disk (301). The toggle plate (305) is fixedly connected to the hemispherical mixing disk (301) via a connecting rod (304).

6. The device for preparing an organic-inorganic composite solid-state battery electrolyte according to claim 5, characterized in that: A circle of inclined guide rings (306) is fixedly connected to a position near the hemispherical mixing disk (301) in the preparation tank (1), and the inclined guide rings (306) are located outside the hemispherical mixing disk (301).

7. The device for preparing an organic-inorganic composite solid-state battery electrolyte according to claim 3, characterized in that: The interiors of the first storage tank (107), the second storage tank (108) and the third storage tank (109) are all fixedly connected with inclined guide blocks (1012), and the inclined guide blocks (1012) are gradually inclined downward near the discharge ports of the first storage tank (107), the second storage tank (108) and the third storage tank (109).

8. The device for preparing an organic-inorganic composite solid-state battery electrolyte according to claim 7, characterized in that: A transparent observation window (1013) is fixedly connected to the surface of the preparation tank (1), and the first storage tank (107), the second storage tank (108) and the third storage tank (109) are all transparent glass tanks.

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