Preparation device of high-purity lithium

Abstract

The utility model discloses a preparation device of high-purity lithium. A high-purity lithium preparation device comprises: an anode structure unit, which comprises an anode tank and an anode current collector, the anode tank is used for accommodating an anode molten salt, and the anode current collector is inserted into the anode molten salt in the anode tank; the cathode structural unit comprises a cathode groove, a solid electrolyte structural part and a cathode current collector, and the cathode groove and the solid electrolyte structural part are sequentially distributed in the first direction and are fixedly connected with each other to form a first cavity; and the lithium storage unit is arranged outside the anode tank and is communicated with the first chamber through the cathode tank to form a closed second chamber. According to the embodiment of the invention, the high-purity lithium metal can be conveniently obtained at low cost, and meanwhile, the high-purity lithium metal can be safely and efficiently collected.

Description

Technical Field

[0001] The present application relates to a device for preparing metallic lithium, and in particular to a device for preparing high-purity lithium. Background Art

[0002] Over the past 30 years, metallic lithium has become a valuable resource as an energy material. As the lightest and lightest metal in nature, lithium is an important component of modern batteries. It is not only widely used in daily mobile phones or laptops, but also widely used in the rapidly expanding electric vehicle industry. It is the preferred negative electrode material for the next generation of high-energy density batteries (such as all-solid-state lithium metal batteries, Li-S batteries, etc.). At the same time, lithium metal is also widely used in light alloys and chemical reagents for the production of organic lithium compounds. The demand for metallic lithium is expected to increase significantly in the next few decades, and the sustainability of lithium resources has received increasing attention from academia and industry.

[0003] At present, the industrial preparation of high-purity metallic lithium adopts the method of electrolyzing high-purity lithium chloride molten salt. This method requires the use of high-purity LiCl and KCl as raw materials. The high-purity molten salt is to prevent the impurities in the molten salt from contaminating the metallic lithium. The high-purity molten salt not only increases the process steps for preparing high-purity metallic lithium, but also increases the cost of raw materials. After preparing high-purity metallic lithium, the traditional process mostly uses manual scooping of lithium liquid, which is complicated to operate and has safety hazards. Utility Model Content

[0004] The embodiment of the present application provides a high-purity lithium preparation device, which can obtain high-purity metallic lithium conveniently and at low cost, and can also collect high-purity metallic lithium safely and efficiently.

[0005] An embodiment of the present application provides a high-purity lithium preparation device, including: an anode structural unit, including an anode tank and an anode current collector, the anode tank is used to accommodate an anode molten salt, and the anode current collector is inserted into the anode molten salt in the anode tank; a cathode structural unit, including a cathode tank, a solid electrolyte structural component and a cathode current collector, the cathode tank and the solid electrolyte structural component are successively distributed along a first direction and are fixedly connected to each other to form a first chamber, the first chamber is inserted into the anode tank through the solid electrolyte structural component. The cathode current collector is at least partially inserted into the cathode molten salt, at least partially extends out of the cathode tank and is insulated and sealed with the cathode tank; and a lithium storage unit, which is arranged outside the anode tank and is connected to the first chamber through the cathode tank to form a closed second chamber.

[0006] In any embodiment of the present application, the lithium storage unit includes a lithium storage tank and a lithium conducting tube, and the lithium conducting tube is connected between the first chamber and the lithium storage tank in a manner of being inclined from the cathode tank toward the lithium storage tank; the second chamber includes the space defined by the first chamber, the lithium storage tank and the lithium conducting tube.

[0007] In any embodiment of the present application, a first through hole is opened on the side wall of the cathode tank, one end of the lithium conducting tube is connected to the first through hole, and the minimum height difference between the first through hole and the cathode molten salt liquid level is 5 to 10 cm.

[0008] In any embodiment of the present application, the lithium conducting tube is detachably connected to the first through port or fixedly connected to the first through port.

[0009] In any embodiment of the present application, the minimum diameter of the lithium conducting tube is 3 to 5 cm.

[0010] In any embodiment of the present application, the angle θ formed between the lithium conducting tube and the side wall of the cathode slot has a value range of 25 to 75°.

[0011] In any embodiment of the present application, there are multiple lithium storage units.

[0012] In any embodiment of the present application, the cathode cell is a cell body including a first open end, the first open end of the cathode cell is butt-connected to the end of the solid electrolyte structure, and the butt-connection is sealed by glass sealing, inorganic salt sealing or mechanical crimping.

[0013] In any embodiment of the present application, there are multiple cathode structural units, the multiple cathode structural units are distributed in an array in the anode tank, the number of anode current collectors is one or more, and the multiple cathode structural units share the anode current collector in a one-to-many manner.

[0014] In any embodiment of the present application, a second through-port is provided in the bottom wall of the cathode slot, the cathode current collector extends out of the cathode slot through the second through-port, and at the second through-port, the bottom wall and the cathode current collector are sealed by glass sealing, inorganic salt sealing or mechanical crimping, wherein the bottom wall of the cathode slot is located at the top of the first chamber.

[0015] The high-purity lithium preparation device of the embodiment of the present application can, through the selective permeability of the solid electrolyte structural parts, allow only lithium ions to exist near the cathode current collector, thereby obtaining high-purity metallic lithium conveniently and at low cost; at the same time, through the setting of the lithium storage unit, the metallic lithium generated in the first chamber enters the second chamber of the lithium storage unit under its own fluidity, thereby replacing the manual scooping process operation and collecting the metallic lithium safely and efficiently. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0017] Figure 1A schematic diagram of the structure of a high-purity lithium preparation device provided in some embodiments of the present application is shown;

[0018] Figure 2 This is a constant voltage electrolysis curve diagram when using the preparation device shown in the present application to electrolyze molten salt to prepare metallic lithium.

[0019] Reference numerals:

[0020] 1- anode structural unit; 11- anode current collector; 12- anode molten salt; 13- anode tank;

[0021] 2- cathode structural unit; 21- cathode current collector; 22- second through port; 23- cathode slot; 24- cathode molten salt; 25- first opening end; 26- solid electrolyte structural member;

[0022] 3-lithium storage unit; 31-lithium conducting tube; 32-lithium storage tank. DETAILED DESCRIPTION

[0023] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0025] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0026] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0027] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0028] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0029] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0030] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0031] In the present application, the term "parallel" includes not only the absolutely parallel situation, but also the roughly parallel situation conventionally recognized in engineering; meanwhile, "vertical" includes not only the absolutely vertical situation, but also the roughly vertical situation conventionally recognized in engineering.

[0032] Combine the following Figure 1-2 The high-purity lithium preparation device provided in the embodiments of the present application is introduced.

[0033] Please also read Figure 1 to Figure 2 , Figure 1 The schematic diagram of the structure of the high-purity lithium preparation device provided in some embodiments of the present application is shown. Figure 2 This is a constant voltage electrolysis curve diagram when using the preparation device shown in the present application to electrolyze molten salt to prepare metallic lithium.

[0034] like Figure 1 As shown, a high-purity lithium preparation device provided in an embodiment of the present application includes: an anode structure unit 1, a cathode structure unit 2 and a lithium storage unit 3. The anode structure unit 1 includes an anode tank 13 and an anode current collector 11. The anode tank 13 is used to accommodate an anode molten salt 12. The anode current collector 11 is inserted into the anode molten salt 12 in the anode tank 13. The cathode structure unit 2 includes a cathode tank 23, a solid electrolyte structure 26 and a cathode current collector 21. The cathode tank 23 and the solid electrolyte structure 26 are successively distributed along a first direction and are fixed to each other to form a first chamber. The first chamber is inserted into the anode molten salt 12 in the anode tank 13 through the solid electrolyte structure 26. The cathode current collector 21 is at least partially inserted into the cathode molten salt 24, at least partially extends out of the cathode tank 23 and is insulated and sealed with the cathode tank 23. The lithium storage unit 3 is arranged outside the anode tank 13, and is connected to the first chamber through the cathode tank 23 to form a closed second chamber.

[0035] By setting the solid electrolyte structure 26, only lithium ions exist near the cathode current collector 21, so that high-purity metallic lithium can be obtained conveniently and at low cost; at the same time, by setting the lithium storage unit 3, the metallic lithium generated in the first chamber enters the second chamber of the lithium storage unit 3 under its own fluidity, thereby replacing the manual scooping process operation and collecting the metallic lithium safely and efficiently.

[0036] In some embodiments, the anode tank 13 can be surrounded by a side wall and a bottom to form a chamber for accommodating the anode molten salt 12. The manner in which the side wall and the bottom are surrounded is not specifically limited and can be adjusted by those skilled in the art as needed. As an example, the side wall and the bottom can be connected to each other by welding to form a chamber for accommodating the anode molten salt 12.

[0037] The material of the anode tank 13 includes at least one of ceramic, stainless steel and refractory bricks. The shape of the anode tank 13 is not specifically limited and can be adjusted by those skilled in the art as required. As an example, the anode tank 13 is cylindrical.

[0038] In some embodiments, the material of the anode current collector 11 may be a conductive material that is stable to the molten salt. As an example, the material of the anode current collector 11 includes at least one of stainless steel, a conductive carbon material, a metal, and an alloy. As an example, the material of the anode current collector 11 may be 304 stainless steel or 216L stainless steel.

[0039] It is understandable that the anode current collector 11 and the solid electrolyte structure 26 may be arranged at a preset distance to prevent direct contact and corrosion of the solid electrolyte structure 26 .

[0040] In some embodiments, the anode molten salt 12 is a low-purity salt or a mixed salt formed by multiple salts, which can conduct lithium ions. The anode molten salt 12 includes at least one of LiF, LiCl, LiBr, LiI and LiNO3, and the anode molten salt 12 also includes at least one of KF, NaF, RbF, CsF, BaF2, KCl, NaCl, RbCl, CsCl, BaCl2, KBr, NaBr, RbBr, CsBr, BaBr2, KI, NaI, RbI, CsI, BaI2, KNO3 and NaNO3, so as to form a eutectic salt system, thereby reducing the reaction temperature of electrolysis and improving the electrolysis efficiency.

[0041] In some embodiments, the material of the cathode tank 23 can be a metal or alloy that is stable to metallic lithium. As an example, the material of the cathode tank 23 is stainless steel and / or tungsten. The cathode tank 23 can be surrounded by a side wall and a bottom to form a chamber for accommodating the cathode molten salt 24. The manner in which the side wall and the bottom are surrounded is not specifically limited, and those skilled in the art can adjust it as needed. As an example, the side wall and the bottom can be connected to each other by welding to form a chamber for accommodating the cathode molten salt 24.

[0042] In some embodiments, the cathode molten salt 24 may be a salt or a mixed salt formed by multiple salts, which can play the role of conducting lithium ions. The cathode molten salt 24 may include at least one of LiI, LiCl, LiBr and LiF. The cathode molten salt 24 may also include at least one of CsI, KI, NaI, KCl, NaCl, CsCl, KBr, CsBr, KF and NaF to form a eutectic salt system, thereby reducing the reaction temperature of electrolysis and improving the electrolysis efficiency.

[0043] It is understandable that the solid electrolyte structure 26 can prevent atoms other than lithium ions from passing through, and can only allow lithium ions to pass through, so as to ensure that only lithium cations undergo reduction reaction on the cathode current collector 21 in the cathode structural unit 2 to produce metallic lithium, thereby improving the purity of metallic lithium. The solid electrolyte structure 26 can exist in different physical forms, and the size specifications are not specifically limited, and those skilled in the art can adjust them as needed. As an example, the physical form of the solid electrolyte structure 26 can be plate-shaped, columnar, bowl-shaped, sagger-shaped, and tubular, so as to match the shape of the cathode slot 23 and facilitate sealing.

[0044] In some embodiments, the material of the solid electrolyte structure 26 includes a polymer electrolyte and / or a compound electrolyte, and the material of the solid electrolyte structure 26 may also be doped with β-Al2O3. The compound electrolyte may include Li7La3Zr2O 12 , Li 6.4 La3Ta 0.6Zr 1.4 O 12 、LiTi2(PO4)3、Li 14 At least one of Zn(GeO4)4, Li2S-P2S5, LiBH4, LiI, Li3PO4, Li2B4O7 and lithium nitride phosphate.

[0045] In some embodiments, the cathode current collector 21 may be made of a metal or alloy that is stable to metallic lithium. As an example, the cathode current collector 21 may be made of stainless steel and / or tungsten.

[0046] In addition, the anode current collector 11 and the cathode current collector 21 are respectively connected to the positive electrode and the negative electrode of the circuit to form a current path, and redox reactions are respectively carried out at the anode current collector 11 and the cathode current collector 21 to produce high-purity metallic lithium.

[0047] It is understandable that the cathode current collector 21 and the solid electrolyte structure 26 may be arranged at a preset distance to prevent direct contact and corrosion of the solid electrolyte structure 26 .

[0048] Optionally, in order to improve safety in industrial production, a detachable part is provided on the outer surface of the side wall of the cathode slot 23 to fix the cathode structural unit 2 .

[0049] Optionally, in order to improve safety in industrial production, a cover plate is provided above the anode tank 13 .

[0050] The device can prepare high-purity metallic lithium. As an example, after the device is assembled according to the above scheme, the device is kept at 400°C and electrolyzed to prepare metallic lithium under the Land test system. The electrochemical curve of the operation process is as follows: Figure 2 As shown, the electrolysis process is constant voltage electrolysis, the voltage is 4.5V, the average current during the electrolysis process can reach about 1A, and the current density is 30mA / cm 2 The prepared metallic lithium product was subjected to ICP test analysis, and its purity could reach 99.999%.

[0051] In some embodiments, the lithium storage unit 3 includes a lithium storage tank 32 and a lithium conducting tube 31, and the lithium conducting tube 31 is connected between the first chamber and the lithium storage tank 32 in a manner that the cathode slot 23 is inclined toward the lithium storage tank 32; the second chamber includes the space defined by the first chamber, the lithium storage tank 32 and the lithium conducting tube 31.

[0052] The connection between the lithium conducting tube 31 and the cathode tank 23 is higher than the connection between the lithium conducting tube 31 and the lithium storage tank 32 , so that the molten metal lithium can flow smoothly along the lithium conducting tube 31 to the lithium storage tank 32 .

[0053] The material of the lithium storage tank 32 can be a metal or alloy that is stable to metallic lithium. As an example, the material of the lithium storage tank 32 is stainless steel and / or tungsten.

[0054] Optionally, in order to facilitate the removal of metallic lithium from the lithium storage tank 32 , a valve may be provided at the bottom of the lithium storage tank 32 .

[0055] In some embodiments, a first through hole is provided on the side wall of the cathode tank 23, one end of the lithium guide tube 31 is connected to the first through hole, and the minimum height difference between the first through hole and the liquid level of the cathode molten salt 24 is 5 to 10 cm. Optionally, the minimum height difference between the first through hole and the liquid level of the cathode molten salt 24 is independently selected from any value among 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, 10 cm, or a range value between any two of them. Within this range, it is possible to prevent the metallic lithium at the interface of the metallic lithium and the cathode molten salt from directly flowing out and bringing out a small amount of molten salt.

[0056] In some embodiments, the lithium conducting tube 31 can be detachably connected or fixedly connected to the first through port, so as to facilitate replacement of the lithium conducting tube 31 or prevent metal lithium from leaking from the connection. The material of the lithium conducting tube 31 can be a metal or alloy that is stable to metal lithium. As an example, the material of the lithium conducting tube 31 is stainless steel and / or tungsten.

[0057] In some embodiments, the minimum diameter of the lithium conducting tube 31 is 3 to 5 cm. Optionally, the minimum diameter of the lithium conducting tube 31 is independently selected from any value of 3.0 cm, 3.5 cm, 4.0 cm, 4.5 cm, 5.0 cm, or any range between the two. Within this range, the molten metal lithium can be ensured to flow smoothly along the lithium conducting tube 31 to the lithium storage tank 32.

[0058] In some embodiments, the angle θ formed between the lithium conducting tube 31 and the side wall of the cathode slot 23 is in the range of 25 to 75°. Optionally, the angle θ formed between the lithium conducting tube 31 and the side wall of the cathode slot 23 is independently selected from any value among 25°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75° or any range between the two. The angle within this range can make the metallic lithium liquid flow into the lithium storage tank 32 better without remaining in the lithium conducting tube 31.

[0059] In some embodiments, the number of lithium storage units is multiple. As an example, the number of lithium storage units may be 1, 2, or 3. A matching lithium storage unit may be set according to the generation rate of metallic lithium so that metallic lithium can be discharged in time to avoid the metallic lithium liquid level being higher than the first through port due to the excessively fast generation rate of metallic lithium.

[0060] In some embodiments, the cathode slot 23 is a slot body including a first open end 25, and the first open end 25 of the cathode slot 23 is butt-connected with the end of the solid electrolyte structure 26, and the butt-connection is sealed by glass sealing, inorganic salt sealing or mechanical crimping. As an example, when the shape of the solid electrolyte structure 26 is U-shaped, the first open end 25 of the cathode slot 23 is butt-connected with the open end (end) of the solid electrolyte structure 26 by glass sealing. As an example, when the shape of the solid electrolyte structure 26 is plate-shaped, the first open end 25 of the cathode slot 23 is butt-connected with the edge end of the solid electrolyte structure 26 by inorganic salt (a mixture of lithium carbonate and potassium carbonate, with a molar ratio of 1:4) sealing. The liquid level of the cathode molten salt 24 can be higher than the sealing point to prevent the generated metallic lithium from contacting the solid electrolyte structure 26 and corroding the solid electrolyte structure 26.

[0061] In some embodiments, there are multiple cathode structural units 2, which are distributed in an array in the anode tank 13, there are one or more anode current collectors 11, and the multiple cathode structural units 2 share the anode current collector 11 in a one-to-many manner.

[0062] Two or more cathode structural units 2 are arranged at intervals from each other and at least two cathode structural units 2 share one anode current collector 11. Each cathode structural unit 2 can be directly placed in the anode molten salt 12. A detachable part is arranged on the outer surface of the cathode slot 23 to fix the cathode structural unit 2, or a bracket is arranged on the inner wall (bottom or side wall) of the anode slot 13 to fix the cathode structural unit 2 to improve the safety of industrial production. Two or more cathode structural units 2 are arranged together in a chamber containing the anode molten salt 12 formed by the anode slot 13, thereby forming a multi-cathode common anode structural arrangement. It can be understood that the number of cathode structural units 2 can be multiple, and the corresponding number of anode current collectors 11 can be one or more. In this case, every two cathode structural units 2 or multiple cathode structural units 2 share one anode current collector 11.

[0063] In some embodiments, the bottom wall of the cathode slot 23 is provided with a second through hole 22, and the cathode current collector 21 extends out of the cathode slot 23 through the second through hole 22, and is sealed at the second through hole 22, between the bottom wall and the cathode current collector 21 by glass sealing, inorganic salt sealing or mechanical compression, wherein the bottom wall of the cathode slot 23 is located at the top of the first chamber. The shape of the cathode current collector 21 is not specifically limited, and those skilled in the art can adjust it as needed. As an example, the shape of the cathode current collector 21 is sheet-like or columnar.

[0064] As an example, the embodiment of the present application provides a high-purity lithium preparation device, including: an anode structural unit 1, a cathode structural unit 2 and a lithium storage unit 3. The anode structural unit 1 includes an anode tank 13 and an anode current collector 11, the anode tank 13 is used to accommodate an anode molten salt 12, and the anode current collector 11 is inserted into the anode molten salt 12 in the anode tank 13. The cathode structural unit 2 includes a cathode tank 23, a solid electrolyte structural member 26 and a cathode current collector 21, the cathode tank 23 and the solid electrolyte structural member 26 are successively distributed along a first direction and are fixed to each other to form a first chamber, the first chamber is inserted into the anode tank 13 by the solid electrolyte structural member 26, the cathode current collector 21 is at least partially inserted into the cathode molten salt 24, at least partially extends out of the cathode tank 23 and is insulated and sealed with the cathode tank 23. The lithium storage unit 3 includes a lithium storage tank 32 and a lithium guide tube 31, and the lithium guide tube 31 is connected between the first chamber and the lithium storage tank 32 in a manner that the cathode tank 23 is inclined toward the lithium storage tank 32.

[0065] As another example, an embodiment of the present application provides a device for preparing high-purity lithium, in which a cylindrical stainless steel with a diameter of 7 cm is selected as the anode tank 13, and 500 g of LiCl-KCl (molar ratio of 1:1) mixed molten salt is added to the anode tank 13; the solid electrolyte structure 26 uses a U-shaped LLZTO ceramic electrolyte tube with an inner diameter of 2 cm and a height of 10 cm; a cylindrical stainless steel is selected as the cathode tank 23, and the tube mouth of the solid electrolyte structure 26 is sealed with glass; a top cover with a second through hole 22 of 1 cm in the center is welded on the top of the cathode tank 23, and the cathode current collector 21 is sealed with glass at the second through hole 22. The cathode current collector 21 is a stainless steel column with a diameter of 3 mm, extending downward from the top of the cathode slot 23 to 1 cm from the bottom of the solid electrolyte structure 26; LiBr-KBr-CsBr (mass ratio of 42.75%:39.08%:18.17%) is added to the solid electrolyte structure 26, and the LiBr-KBr-CsBr molten salt level is higher than the tube mouth of the solid electrolyte structure 26; a first through port is opened 5 cm above the cathode molten salt level, and then a stainless steel lithium guide tube 31 with an inner diameter of 3 cm is welded obliquely downward, and the angle between the lithium guide tube and the side wall of the cathode slot is 45°; a stainless steel lithium storage tank 32 is welded at the other end of the lithium guide tube 31.

[0066] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A device for preparing high-purity lithium, characterized in that: include: An anode structural unit comprises an anode tank and an anode current collector, wherein the anode tank is used to contain an anode molten salt, and the anode current collector is inserted into the anode tank and arranged with the anode molten salt; A cathode structural unit, comprising a cathode slot, a solid electrolyte structural member and a cathode current collector, wherein the cathode slot and the solid electrolyte structural member are successively distributed along a first direction and are fixedly connected to each other to form a first chamber, wherein the first chamber is provided by inserting the anode molten salt into the anode slot through the solid electrolyte structural member, and the cathode current collector is at least partially inserted into the cathode molten salt, at least partially extends out of the cathode slot and is insulated and sealedly connected to the cathode slot; and The lithium storage unit is arranged outside the anode tank and is connected with the first chamber through the cathode tank to form a closed second chamber.

2. The preparation device according to claim 1, characterized in that: The lithium storage unit comprises a lithium storage tank and a lithium conducting tube, wherein the lithium conducting tube is connected between the first chamber and the lithium storage tank in a manner of being inclined from the cathode tank toward the lithium storage tank; The second chamber includes a space defined by the first chamber, the lithium storage tank and the lithium conducting tube.

3. The preparation device according to claim 2, characterized in that: The cathode tank side wall is provided with a first through hole, one end of the lithium conducting tube is connected to the first through hole, and the minimum height difference between the first through hole and the cathode molten salt liquid level is 5-10 cm.

4. The preparation device according to claim 3, characterized in that: The lithium conducting tube can be detachably connected to the first through port or fixedly connected to the first through port.

5. The preparation device according to claim 2, characterized in that: The minimum diameter of the lithium conducting tube is 3 to 5 cm.

6. The preparation device according to claim 2, characterized in that: The value range of the angle θ formed between the lithium conducting tube and the side wall of the cathode slot is 25-75°.

7. The preparation device according to claim 1, characterized in that: The number of the lithium storage units is multiple.

8. The preparation device according to claim 1, characterized in that: The cathode cell is a cell body including a first open end, the first open end of the cathode cell is butt-jointed to the end of the solid electrolyte structure, and the butt-joint is sealed by glass sealing, inorganic salt sealing or mechanical crimping.

9. The preparation device according to claim 1, characterized in that: The number of the cathode structural units is multiple, and the multiple cathode structural units are distributed in an array in the anode tank. The number of the anode current collectors is one or more, and the multiple cathode structural units share the anode current collector in a one-to-many manner.

10. The preparation device according to claim 1, characterized in that: The bottom wall of the cathode slot is provided with a second through-port, the cathode current collector extends out of the cathode slot through the second through-port, and the bottom wall and the cathode current collector are sealed at the second through-port by glass sealing, inorganic salt sealing or mechanical crimping, wherein the bottom wall of the cathode slot is located at the top of the first chamber.

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