Lithium supplementing device, battery production system and lithium supplementing method of pole piece

Abstract

The invention provides a lithium supplementing device, a battery production system and a lithium supplementing method of a pole piece. The lithium supplementing device comprises a shell, an unwinding mechanism, a winding mechanism and an evaporation mechanism. The shell is provided with a first cavity, a second cavity, a third cavity, a first opening and a second opening, the first opening communicates with the first cavity and the second cavity, the second opening communicates with the first cavity and the third cavity, and the second cavity is used for receiving passivation gas. The unwinding mechanism is arranged in the first cavity and is used for arranging a base material to be supplemented with lithium; the winding mechanism is arranged in the second cavity and used for pulling the base material to penetrate through the first opening and winding the base material. The evaporation mechanism is arranged in the third cavity, and lithium is evaporated on the surface of the base material through the second opening by the evaporation mechanism. The reliability of the battery monomer can be improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a lithium replenishment device, a battery production system, and a method for replenishing lithium on electrodes. Background Technology

[0002] Battery cells are widely used in electronic devices such as mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools. Battery cells can include nickel-cadmium battery cells, nickel-metal hydride battery cells, lithium-ion battery cells, and rechargeable alkaline zinc-manganese battery cells, among others.

[0003] In the development of battery technology, improving the reliability of individual battery cells has always been a research direction. Summary of the Invention

[0004] In view of the above problems, this application provides a lithium replenishment device, a battery production system, and a lithium replenishment method for electrodes, which can improve the reliability of battery cells.

[0005] In a first aspect, this application provides a lithium replenishment device, comprising a housing, an unwinding mechanism, a winding mechanism, and a vapor deposition mechanism. The housing has a first cavity, a second cavity, a third cavity, a first opening, and a second opening. The first opening connects the first cavity and the second cavity, and the second opening connects the first cavity and the third cavity. The second cavity is used to receive passivation gas. The unwinding mechanism is disposed in the first cavity and is used to hold the substrate to be replenished with lithium. The winding mechanism is disposed in the second cavity and is used to pull the substrate through the first opening and wind it up. The vapor deposition mechanism is disposed in the third cavity and vapor deposits lithium onto the surface of the substrate through the second opening.

[0006] In the above scheme, by setting a second cavity in the lithium replenishment device, after the lithium is deposited and during the winding process, the substrate of the electrode comes into contact with the passivation gas, and the lithium on the substrate is passivated by the passivation gas, so that a dense passivation layer is formed on the lithium-plated surface of the substrate, thereby reducing the risk of lithium being corroded in the air, reducing the risk of fire or even explosion caused by direct contact between lithium and water vapor, and improving the reliability of the battery cell.

[0007] In some embodiments, the lithium replenishment device further includes a first partition and a second partition, the first partition being disposed between the first cavity and the second cavity and having a first opening, and the second partition being disposed between the first cavity and the third cavity and having a second opening.

[0008] In the above scheme, by setting the first partition and the second partition, it is beneficial to simplify the separation structure of the first cavity, the second cavity and the third cavity inside the shell, thereby reducing the manufacturing cost of the shell.

[0009] In some embodiments, the first cavity and the third cavity are arranged sequentially along a first direction, thereby reducing the difficulty of vapor deposition and improving production efficiency.

[0010] In some embodiments, the lithium replenishment device further includes a plurality of guide rollers disposed between the unwinding mechanism and the winding mechanism to guide the substrate transmission.

[0011] In the above scheme, by setting multiple guide rollers to guide the transmission direction of the substrate, the transmission mechanism of the substrate is simplified and the manufacturing cost of the lithium replenishment device is reduced.

[0012] In some embodiments, the guide roller includes a first guide roller disposed on the side of the second opening opposite to the third cavity, and the first guide roller is disposed on the periphery of the second opening.

[0013] In the above scheme, by setting the first guide roller so that the substrate can move above the second opening, the possibility of wrinkles or other phenomena occurring during the substrate transmission process during vapor deposition is reduced, thereby reducing the possibility of creases in the substrate causing a decrease in production yield and improving the reliability of the battery cell.

[0014] In some embodiments, the guide roller further includes a second guide roller disposed on the drive path between the second opening and the winding mechanism. The number of second guide rollers includes a plurality of them, and at least a portion of the plurality of second guide rollers are disposed in the second cavity.

[0015] In the above scheme, the above settings allow a portion of the expanded vapor-deposited substrate to be placed in the second cavity, increasing the passivation time of the expanded vapor-deposited substrate, further increasing the thickness of the passivation layer formed by passivation, thereby improving the protective performance of the passivation layer and improving the reliability of the battery cell.

[0016] In some embodiments, the second cavity includes a first sub-cavity and a second sub-cavity, a winding mechanism is disposed in the first sub-cavity, at least a portion of the second guide rollers of a plurality of second guide rollers are disposed in the second sub-cavity, and at least one of the first sub-cavity and the second sub-cavity is used to receive passivation gas.

[0017] In the above scheme, the substrate after vapor deposition is further passivated to improve the flexibility of passivation, reduce the risk of thermal runaway of battery cells during charging and discharging, and improve the reliability of battery cells.

[0018] In some embodiments, the lithium replenishment device further includes a first vacuum valve for introducing passivation gas into the second chamber to control the gas pressure in the second chamber, thereby improving the lithium replenishment effect and simultaneously improving the density of the passivation layer and the reliability of the battery.

[0019] In some embodiments, the vapor deposition mechanism includes a vapor deposition element and a baffle, the vapor deposition element being located on the side of the baffle facing away from the second opening, and the baffle including a plurality of openings and a shielding portion surrounding the openings.

[0020] The above-described solution improves the precision of controlling the diffusion direction and range of lithium vapor, reduces the possibility of localized over-plating or under-plating, and enhances the uniformity of lithium vapor deposition. Furthermore, it reduces the likelihood of lithium vapor directly spraying onto a predetermined area of ​​the substrate surface, thereby reducing the possibility of lithium vapor contaminating that area and improving the reliability of the battery cell.

[0021] Secondly, embodiments of this application provide a battery production system, including the lithium replenishment device in any of the foregoing embodiments.

[0022] Thirdly, embodiments of this application provide a method for lithium replenishment of an electrode. The method includes evacuating a first cavity, a second cavity, and a third cavity. A passivating gas is then introduced into the second cavity. An unwinding mechanism and a rewinding mechanism are controlled to pull a substrate for vapor deposition, and the vapor-deposited substrate enters the second cavity to undergo a passivation reaction with the passivating gas, thereby forming a passivation layer on the surface of the lithium.

[0023] In some embodiments, the passivation gas includes oxygen and an inert gas, wherein the oxygen content is 30 vol% to 70 vol%.

[0024] In the above scheme, oxygen reacts with lithium to form a dense oxide film on the lithium-plated surface, thereby slowing down the corrosion of lithium by reactions with other gases in the air. Furthermore, by mixing inert gas and oxygen, the oxygen content is reduced, decreasing the possibility of an explosion during heating.

[0025] In some embodiments, the step of filling the second cavity with passivating gas includes: filling the second cavity with passivating gas at a first rate of 0.02 MPa to 0.05 MPa.

[0026] In the above scheme, during the vapor deposition process, the second vacuum valve and the third vacuum valve continuously evacuate the first chamber and the third chamber, respectively. By filling the passivation gas at the first rate, the influence of the passivation gas on the gas pressure in the first chamber and the third chamber when it enters the second chamber is reduced. On the other hand, the possibility of insufficient passivation gas due to the extraction of passivation gas in the second chamber by the second vacuum valve and the third vacuum valve during operation is reduced, thereby improving the passivation effect and improving the reliability of the battery cell.

[0027] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of a lithium replenishment device provided in an embodiment of this application;

[0030] Figure 2 This is a schematic diagram of another lithium replenishment device provided in the embodiments of this application;

[0031] Figure 3 This is a schematic diagram of another lithium replenishment device provided in the embodiments of this application;

[0032] Figure 4 This is a schematic flowchart of a lithium replenishment method for an electrode provided in an embodiment of this application.

[0033] Marker description

[0034] 10. Shell; 11. First cavity; 12. Second cavity; 121. First sub-cavity; 122. Second sub-cavity; 13. Third cavity;

[0035] 20. Unwinding mechanism;

[0036] 30. Receiving and unloading mechanism;

[0037] 40. Evaporation deposition mechanism; 41. Evaporation deposition component; 42. Baffle;

[0038] 50. Substrate;

[0039] 61. First partition; 62. Second partition;

[0040] 70. Guide roller; 71. First guide roller; 72. Second guide roller;

[0041] 81. First vacuum valve; 82. Second vacuum valve; 83. Third vacuum valve;

[0042] K1, first opening; K2, second opening; K3, third opening;

[0043] X, the first direction. Detailed Implementation

[0044] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0046] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0047] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0048] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0049] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0050] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0051] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0052] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0053] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0054] Unless otherwise specified, all steps of this application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order; for example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0055] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0056] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0057] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator, with the separator positioned between the positive and negative electrodes. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0058] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0059] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0060] As an example, the positive current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, nickel alloys, titanium, or silver. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0061] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.8 Co 0.15 Al 0.05 At least one of O2 and its modified compounds. Modified compounds refer to substances obtained by modification methods such as doping or coating based on the above-mentioned substances.

[0062] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, a positive electrode active material is filled and / or deposited within the foamed metal.

[0063] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0064] As an example, the negative electrode current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, nickel alloys, titanium, or silver. The composite current collector may include a polymer material substrate and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0065] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0066] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0067] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials for battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0068] In some embodiments, the negative electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When foamed metal is used as the negative electrode sheet, the surface of the foamed metal may or may not have a negative electrode active material.

[0069] As an example, negative electrode active materials can be filled or / and deposited within the negative electrode current collector.

[0070] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0071] Currently, judging from market trends, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely applied in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of battery device applications, market demand is also constantly increasing.

[0072] In related technologies, battery devices include multiple battery cells. The electrode components within each cell enable the battery's charging and discharging functions. The lithium-ion exchange between the positive and negative electrodes allows the battery to store and release electrical energy. The positive electrode material includes lithium-ion-containing materials. Due to process issues during preparation, the positive electrode requires a lithium replenishment process to increase its lithium content and ensure the energy density of the battery cell. The lithium replenishment process involves vapor-depositing lithium onto the positive electrode substrate. The deposited substrate is then wound into a roll and placed in a space filled with passivating gas to passivate the lithium, forming a dense passivation layer on the lithium-plated surface. However, the interior of the wound substrate cannot fully react with the passivating gas, preventing some lithium from forming a dense passivation layer. This leads to lithium corrosion in the air and even fires caused by contact with moisture, reducing the reliability of the battery cell.

[0073] Based on the above-mentioned technical problems, this application provides a technical solution. By setting a second cavity in the lithium replenishment device, after the lithium is deposited and during the winding process, the substrate of the electrode comes into contact with the passivation gas, and the lithium on the substrate is passivated by the passivation gas, so that a dense passivation layer is formed on the lithium-plated surface of the substrate, thereby reducing the risk of lithium being corroded in the air, reducing the risk of fire or even explosion caused by direct contact between lithium and water vapor, and improving the reliability of the battery cell.

[0074] Figure 1 This is a schematic diagram of a lithium replenishment device provided in an embodiment of this application. Figure 2 This is a schematic diagram of another lithium replenishment device provided in the embodiments of this application.

[0075] Please see Figure 1 and Figure 2 This application provides a lithium replenishment device, which includes a housing 10, an unwinding mechanism 20, a winding mechanism 30, and a vapor deposition mechanism 40. The housing 10 has a first cavity 11, a second cavity 12, a third cavity 13, a first opening K1, and a second opening K2. The first opening K1 connects the first cavity 11 and the second cavity 12, and the second opening K2 connects the first cavity 11 and the third cavity 13. The second cavity 12 is used to receive passivation gas. The unwinding mechanism 20 is disposed in the first cavity 11 and is used to place the substrate 50 to be replenished with lithium. The winding mechanism 30 is disposed in the second cavity 12 and is used to pull the substrate 50 through the first opening K1 and wind the substrate 50. The vapor deposition mechanism 40 is disposed in the third cavity 13 and vapor deposits lithium onto the surface of the substrate 50 through the second opening K2.

[0076] Optionally, the shell 10 can be a single integral structure, for example, the shell 10 can be composed of multiple connected wall portions. Alternatively, the shell 10 can be a split structure, formed by a first shell portion 10 and a second shell portion 10. Of course, the shell 10 can also be formed by multiple shell portions 10.

[0077] Optionally, the first cavity 11 and the second cavity 12 can be separated by a baffle 42, a retaining wall, or other structures. Alternatively, the first cavity 11 and the third cavity 13 can be separated by a baffle 42, a retaining wall, or other structures. Alternatively, the second cavity 12 and the third cavity 13 can be separated by the first cavity 11; for example, a portion of the first cavity 11 may be located between the second cavity 12 and the third cavity 13. Or, the second cavity 12 and the first cavity 11 can be separated by the third cavity 13; for example, a portion of the third cavity 13 may be located between the second cavity 12 and the first cavity 11.

[0078] Optionally, the first cavity 11 and the second cavity 12 are connected through a first opening K1.

[0079] Optionally, the first cavity 11 and the third cavity 13 are connected by a second opening K2, and the first cavity 11 is located above the third cavity 13.

[0080] The unwinding mechanism 20 is used to unwind the rolled substrate 50 and convey the unwound substrate 50 through the guiding mechanism so that the substrate 50 can pass through the second opening K2.

[0081] The winding mechanism 30 is used to wind the unfolded and vapor-deposited substrate 50 into a roll. Optionally, multiple guiding mechanisms are provided between the unwinding mechanism 20 and the winding mechanism 30. The unwinding mechanism 20, the winding mechanism 30, and the multiple guiding mechanisms together form the transmission path of the substrate 50, and the substrate 50 is driven along the transmission path.

[0082] The vapor deposition mechanism 40 is used to heat and evaporate elemental lithium or other lithium materials and deposit them onto the surface of the substrate 50. Optionally, the vapor deposition mechanism 40 may include a vapor deposition element 41, which has a receiving space for containing lithium. A heating mechanism may be provided below the vapor deposition element 41 to vapor deposit the lithium within it. The evaporated lithium is then deposited onto the surface of the substrate 50 through the second opening K2. Optionally, the substrate 50 may be made of foamed metal, a porous material filled with interconnected or closed pores. During the vapor deposition process, some lithium enters the pores. After the lithium-plated surface of the substrate 50 expands and enters the second cavity 12, it undergoes a passivation reaction with a passivating gas. The passivating gas can also enter the pores and react with the lithium within them to further improve reliability.

[0083] The second chamber 12 is used to receive passivating gas. The substrate 50 enters the second chamber 12 and undergoes a passivation reaction with the passivating gas before winding, so that the lithium plating on the substrate 50 forms a dense passivation layer between windings. It is understood that passivation is a chemical process in which a dense and stable oxide or other compound film is formed on the material surface, which protects the material from further corrosion or chemical reactions. Passivation reactions typically occur on metals and their alloys, but can also occur on some non-metallic materials.

[0084] Alternatively, the winding mechanism 30 can be wound onto the traction substrate 50 by rotating it.

[0085] Optionally, the shape of the first opening K1 can match the shape of the substrate 50, for example, the shape of the first opening K1 is rectangular.

[0086] Optionally, the shape of the second opening K2 can be matched to the required vapor deposition area of ​​the substrate 50. For example, the second opening K2 can be a rectangular opening or a square opening. Alternatively, the second opening K2 can be a plurality of spaced-apart rectangular openings or square openings.

[0087] In this embodiment of the application, by setting a second cavity 12 in the lithium replenishment device, after the lithium is deposited and during the winding process, the substrate 50 of the electrode comes into contact with the passivation gas, and the lithium on the substrate 50 is passivated by the passivation gas, so that a dense passivation layer is formed on the lithium-plated surface of the substrate 50, thereby reducing the risk of lithium being corroded in the air, reducing the risk of fire or even explosion caused by direct contact between lithium and water vapor, and improving the reliability of the battery cell.

[0088] In some alternative embodiments, please refer to Figure 1 and Figure 2The lithium replenishment device also includes a first partition 61 and a second partition 62. The first partition 61 is disposed between the first cavity 11 and the second cavity 12 and has a first opening K1. The second partition 62 is disposed between the first cavity 11 and the third cavity 13 and has a second opening K2.

[0089] Optionally, the housing 10 may include an outer shell, with a first partition 61 connected to the outer shell, separating the first cavity 11 and the second cavity 12. Optionally, a second partition 62 connected to the outer shell separates the first cavity 11 and the third cavity 13. Optionally, the first partition 61 may be detachably connected to the outer shell to allow for replacement of different sizes of the first opening K1, thereby adapting to substrates 50 with different widths and thicknesses. Optionally, the second partition 62 may be detachably connected to the outer shell to allow for replacement of different sizes of the second opening K2, thereby adapting to substrates 50 with different vapor deposition areas.

[0090] The embodiments of this application, by setting the first partition 61 and the second partition 62, facilitate the simplification of the separation structure of the first cavity 11, the second cavity 12 and the third cavity 13 inside the shell, thereby reducing the manufacturing cost of the shell.

[0091] In some alternative embodiments, please refer to Figure 1 and Figure 2 The first cavity 11 and the third cavity 13 are arranged sequentially along the first direction X, thereby reducing the difficulty of vapor deposition and improving production efficiency.

[0092] Optionally, the first direction X can be perpendicular to the horizontal plane. Of course, the first direction X can also be parallel to the horizontal plane. Taking the first direction X being perpendicular to the horizontal plane as an example, the first cavity 11 can be located above the third cavity 13. Of course, the first cavity 11 can also be located below the third cavity 13.

[0093] Optionally, at least a portion of the first cavity 11 and the second cavity 12 are sequentially arranged along a second direction. For example, a portion of the first cavity 11 and the second cavity 12 are sequentially arranged along a second direction, with another portion of the first cavity 11 located between the second cavity 12 and the third cavity 13. Optionally, the first direction X and the second direction intersect.

[0094] In some alternative embodiments, please refer to Figure 1 and Figure 2 The lithium replenishment device also includes multiple guide rollers 70, which are disposed between the unwinding mechanism 20 and the winding mechanism 30 to guide the substrate 50 in motion.

[0095] The substrate 50 on the transmission path between the unwinding mechanism 20 and the second opening K2 is the undeposited substrate 50, the substrate 50 above the second opening K2 is the substrate 50 during the deposition process, and the substrate 50 on the transmission path between the second opening K2 and the winding mechanism 30 is the deposited substrate 50. Optionally, the undeposited substrate 50 can be driven to the area above the second opening K2 by multiple guide rollers 70, passing above the second opening K2 to form the deposited substrate 50, and then driven to the winding mechanism 30 by multiple guide rollers 70.

[0096] This application embodiment simplifies the transmission mechanism of the substrate 50 and reduces the manufacturing cost of the lithium replenishment device by setting multiple guide rollers 70 to guide the transmission direction of the substrate 50.

[0097] In some alternative embodiments, please refer to Figure 1 and Figure 2 The guide roller 70 includes a first guide roller 71, which is disposed on the side of the second opening K2 facing away from the third cavity 13, and is disposed on the periphery of the second opening K2.

[0098] Optionally, the number of first guide rollers 71 may include two, with the two first guide rollers 71 respectively disposed on both sides of the second opening K2 along the length direction of the substrate 50, and the substrate 50 being driven along its own length direction to pass through the second opening K2.

[0099] Optionally, the two first guide rollers 71 can also be respectively disposed on both sides of the second opening K2 along the width direction of the substrate 50, the substrate 50 is driven along its own length direction, and the two sides of the substrate 50 along the width direction respectively drive the first guide rollers 71 to rotate.

[0100] Optionally, the first guide roller 71 is disposed in the first cavity 11. Alternatively, the first guide roller 71 is disposed in the second opening K2, and the first guide roller 71 is rotatably connected to the side wall of the second opening K2.

[0101] In this embodiment, by setting a first guide roller 71, the substrate 50 can move above the second opening K2, thereby reducing the possibility of wrinkles or other phenomena occurring during the transmission of the substrate 50 during vapor deposition, and further reducing the possibility of creases on the substrate 50 causing a decrease in production yield, thus improving the reliability of the battery cell.

[0102] In some alternative embodiments, please refer to Figure 1 and Figure 2 The guide roller 70 also includes a second guide roller 72, which is disposed on the transmission path between the second opening K2 and the winding mechanism 30. The number of second guide rollers 72 includes a plurality of them, and at least a portion of the plurality of second guide rollers 72 are disposed in the second cavity 12.

[0103] Optionally, the number of second guide rollers 72 may include one, two, three or more.

[0104] Optionally, there are two first guide rollers 71. The first first guide roller 71 and the second first guide roller 71 are located on both sides of the second opening K2 along the length of the substrate 50, respectively. The orthographic projection of the first first guide roller 71 on the second partition 62 is located on the side of the second opening K2 closer to the winding mechanism 30. The second guide roller 72 can be disposed between the first first guide roller 71 and the winding mechanism 30.

[0105] Optionally, multiple second guide rollers 72 may be disposed in the second cavity 12.

[0106] Optionally, a portion of the second guide rollers 72 are disposed in the second cavity 12, and another portion of the second guide rollers 72 are disposed in the first cavity 11.

[0107] In these alternative embodiments, the above-described configuration allows for an increased passivation time of a portion of the expanded vapor-deposited substrate 50 within the second cavity 12, further increasing the thickness of the passivation layer formed by passivation, thereby improving the protective performance of the passivation layer and enhancing the reliability of the battery cell.

[0108] Figure 3 This is a schematic diagram of another lithium replenishment device provided in the embodiments of this application.

[0109] In some alternative embodiments, please refer to Figure 3 The second cavity 12 includes a first sub-cavity 121 and a second sub-cavity 122. The winding mechanism 30 is disposed in the first sub-cavity 121. At least a portion of the second guide rollers 72 are disposed in the second sub-cavity 122. At least one of the first sub-cavity 121 and the second sub-cavity 122 is used to receive passivation gas.

[0110] The first sub-cavity 121 and the second sub-cavity 122 may be separated by a partition. Optionally, the second sub-cavity 122 may be separated from other cavities by a third partition. Optionally, the third partition may have a third opening K3. The number of third openings may include two. The winding mechanism 30 pulls the substrate 50 through one of the third openings K3 into the second sub-cavity 122 and exits the second sub-cavity 122 through the other third opening K3.

[0111] In some examples, a portion of the multiple second guide rollers 72 are disposed in the second sub-cavity 122, and another portion of the second guide rollers 72 are disposed in the first sub-cavity 121. In other examples, all of the multiple second guide rollers 72 are disposed in the second sub-cavity 122. In still other examples, a portion of the multiple second guide rollers 72 are disposed in the first sub-cavity 121, a portion of the second guide rollers 72 are disposed in the second sub-cavity 122, and a portion of the second guide rollers 72 are disposed in the first cavity 11.

[0112] In some examples, the first sub-cavity 121 is used to receive passivating gas, such that both the partially unfolded substrate 50 and the rolled substrate are disposed within the cavity filled with passivating gas. In other examples, the second sub-cavity 122 is used to receive passivating gas, such that a partially unfolded substrate 50 is disposed within the cavity filled with passivating gas. In still other examples, both the first sub-cavity 121 and the second sub-cavity 122 are used to receive passivating gas.

[0113] The embodiments of this application, through the above-described settings, further passivate the substrate 50 after vapor deposition, thereby improving the flexibility of the passivation process, reducing the risk of thermal runaway of the battery cell during charging and discharging, and improving the reliability of the battery cell.

[0114] In some alternative embodiments, please refer to Figures 1 to 3 The lithium replenishment device also includes a first vacuum valve 81, which is used to introduce passivation gas into the second chamber 12 to control the gas pressure of the second chamber 12, thereby improving the lithium replenishment effect and improving the density of the passivation layer and the reliability of the battery.

[0115] Optionally, the first vacuum valve 81 can be used to evacuate the second chamber 12.

[0116] Optionally, the first vacuum valve 81 can also be connected to other gas storage devices to allow the passivating gas in the gas storage device to enter the second chamber 12.

[0117] Optionally, the lithium replenishment device may also include a second vacuum valve 82 for evacuating the first chamber 11.

[0118] Optionally, the lithium replenishment device may also include a third vacuum valve 83 for evacuating the third chamber 13.

[0119] In this embodiment of the application, by setting a first vacuum valve 81 to evacuate the second chamber 12 and fill it with passivating gas, on the one hand, the evacuation of the first chamber 11 and the third chamber 13 can be unaffected, and on the other hand, the first vacuum valve 81 can be connected to the external environment to discharge the gas in the second chamber 12 to the external environment. Furthermore, the first vacuum valve 81 can also be connected to a gas storage device to fill the second chamber 12 with passivating gas.

[0120] In some alternative embodiments, please refer to Figure 1 The vapor deposition mechanism 40 includes a vapor deposition component 41 and a baffle 42. The vapor deposition component is located on the side of the baffle facing away from the second opening K2. The baffle 42 includes multiple openings and a shielding portion that surrounds the openings.

[0121] Optionally, the vapor-deposited part 41 may include a crucible.

[0122] Optionally, the baffle 42 is located between the vapor-deposited part 41 and the second opening K2. The opening allows lithium vapor to pass through and diffuse onto the surface of the substrate 50, while the baffle prevents lithium vapor from being directly sprayed onto a predetermined area on the surface of the substrate 50.

[0123] For example, the substrate 50 can be cut into two parts along its length during subsequent fabrication. The cut areas of the two parts of the substrate 50 can be blank areas of the substrate 50, and the shielding parts shield the blank areas of the two parts of the substrate 50. Of course, the substrate 50 can also be cut into three, four, or even more parts, with the number of shielding parts matching the number of cut parts of the substrate 50. For example, if the substrate 50 is cut into two parts, the number of shielding parts is one; if the substrate 50 is cut into three parts, the number of shielding parts is two; if the substrate 50 is cut into four parts, the number of shielding parts is three.

[0124] By setting the above-described configuration, this embodiment of the application can improve the control precision of the diffusion direction and range of lithium vapor, reduce the possibility of local over-plating or under-plating, and improve the uniformity of lithium vapor deposition. Furthermore, it can reduce the possibility of lithium vapor directly spraying onto a predetermined area on the surface of the substrate 50, thereby reducing the possibility of lithium vapor contaminating the predetermined area and improving the reliability of the battery cell.

[0125] Secondly, embodiments of this application provide a battery production system, including the lithium replenishment device in any of the foregoing embodiments.

[0126] Since the battery production system provided in this application includes the lithium replenishment device of any of the above embodiments, the battery production system provided in this application has the beneficial effects of the lithium replenishment device of any of the above embodiments, which will not be repeated here.

[0127] Figure 4 This is a schematic flowchart of a lithium replenishment method for an electrode provided in an embodiment of this application.

[0128] like Figure 4 As shown, in a third aspect, embodiments of this application provide a method for replenishing lithium on an electrode, the method comprising the following steps.

[0129] S100, Evacuate the first cavity 11, the second cavity 12 and the third cavity 13.

[0130] S200, Passivating gas is introduced into the second cavity 12.

[0131] S300, the unwinding mechanism 20 and the winding mechanism 30 pull the substrate 50 to perform vapor deposition on the substrate, and the vapor-deposited substrate 50 enters the second cavity 12 to undergo a passivation reaction with the passivation gas so that a passivation layer is formed on the surface of lithium.

[0132] In steps S100 to S300, the housing 10 can be opened first, the lithium material placed in the vapor deposition mechanism 40, and then the housing 10 closed. After closing the housing, the first chamber 11, the second chamber 12, and the third chamber 13 are evacuated to reach preset gas pressures. Then, the lithium in the vapor deposition mechanism 40 is heated to evaporate the lithium. When the lithium vapor deposition rate and the transmission rate of the substrate 50 reach preset requirements, the substrate 50 can be allowed to move. At this time, passivating gas can be introduced into the second chamber 12 through the first vacuum valve 81 to form a passivation layer on the surface of the lithium plating. When the substrate 50 has been completely vapor-deposited and wound onto the winding mechanism 30, the heating of the lithium is stopped, as are the winding mechanism 30 and the unwinding mechanism 20. The pressure in the first chamber 11 and the third chamber 13 is released through the second vacuum valve 82 and the third vacuum valve 83, and the housing 10 is opened to remove the substrate 50 for subsequent preparation.

[0133] In this embodiment of the application, the lithium replenishment preparation method described above allows the substrate 50 to fully contact the passivation gas, enabling the gas to penetrate deep into the internal pores of the substrate 50. At the same time, the passivation time is increased, allowing the substrate 50 to be fully passivated and improving the storage resistance of the substrate 50.

[0134] Optionally, the first chamber 11 can achieve a vacuum level of 7×10 after evacuation. -2 Pa ~ 5 × 10 -3 Pa.

[0135] For example, the air pressure in the first cavity 11 is 7 × 10⁻⁶. -2 Pa, 6×10 -2 Pa, 3×10 -2 Pa, 1×10 -2 Pa, 7×10 -3 Pa or 5×10 -2 Pa.

[0136] Optionally, the third chamber 13 can be evacuated to a vacuum level of 7×10⁻⁶. -3 Pa ~ 5 × 10 -4 Pa.

[0137] For example, the air pressure in the third chamber 13 is 7 × 10⁻⁶. -3 Pa, 6×10 -3 Pa, 3×10-3 Pa, 1×10 -3 Pa, 7×10 -4 Pa or 5×10 -4 Pa.

[0138] Optionally, when filling the second cavity 12 with passivating gas, a preset volume of passivating gas can be filled into the second cavity 12 at one time. Of course, the second cavity 12 can also be continuously filled with passivating gas at a preset rate.

[0139] In some alternative embodiments, the passivation gas includes oxygen and an inert gas, with the oxygen content ranging from 30 vol% to 70 vol%.

[0140] Optionally, the oxygen content may include 30 vol%, 40 vol%, 45 vol%, 50 vol%, 60 vol%, 65 vol%, or 70 vol%.

[0141] Alternatively, the inert gas may include one or more combinations of helium (He), neon (Ne), and argon (Ar).

[0142] In this embodiment, the reaction between oxygen and lithium forms a dense oxide film on the lithium plating surface, thereby slowing down the corrosion of lithium by reactions with other gases in the air. Furthermore, by mixing an inert gas with oxygen, the oxygen content is reduced, decreasing the possibility of an explosion during heating.

[0143] In some alternative embodiments, the step of filling the second cavity with passivating gas includes: filling the second cavity with passivating gas at a first rate of 0.02 MPa to 0.05 MPa.

[0144] Optionally, the passivation gas filling rate may include 0.02 MPa, 0.03 MPa, 0.04 MPa or 0.05 MPa.

[0145] In these alternative embodiments, during the vapor deposition process, the second vacuum valve 82 and the third vacuum valve 83 continuously evacuate the first chamber 11 and the third chamber 13, respectively. By filling the first chamber with passivating gas at a first rate, the influence of the passivating gas entering the second chamber 12 on the gas pressure in the first chamber 11 and the third chamber 13 is reduced. On the other hand, the possibility of insufficient passivating gas due to the extraction of passivating gas from the second chamber 12 by the second vacuum valve 82 and the third vacuum valve 83 during operation is reduced, thereby improving the passivation effect and the reliability of the battery cell.

[0146] According to some embodiments of this application, please refer to Figure 1 and Figure 2The lithium replenishment device includes a housing 10, an unwinding mechanism 20, a winding mechanism 30, and a vapor deposition mechanism 40. The housing 10 has a first cavity 11, a second cavity 12, a third cavity 13, a first opening K1, and a second opening K2. The first opening connects the first cavity 11 and the second cavity 12, and the second opening K2 connects the first cavity 11 and the third cavity 13. The second cavity 12 is used to receive passivation gas. The unwinding mechanism 20 is located in the first cavity 11 and is used to place the substrate 50 to be replenished with lithium. The winding mechanism 30 is located in the second cavity 12 and is used to pull the substrate 50 through the first opening K1 and wind the substrate 50. The vapor deposition mechanism 40 is located in the third cavity 13 and vapor deposits lithium onto the surface of the substrate 50 through the second opening K2.

[0147] The lithium replenishment device also includes a first partition 61 and a second partition 62. The first partition is disposed between the first cavity 11 and the second cavity 12, and the first partition 61 has a first opening K1. The second partition 62 is disposed between the first cavity 11 and the third cavity 13, and the second partition 62 has a second opening K2. The first cavity 11 and the third cavity 13 are arranged sequentially along the first direction X.

[0148] The lithium replenishment device also includes multiple guide rollers 70, including a first guide roller 71 disposed on the side of the second opening K2 facing away from the third cavity 13, and the first guide roller 71 is disposed on the periphery of the second opening K2. The guide rollers 70 also include second guide rollers 72 disposed on the transmission path between the second opening K2 and the winding mechanism 30. Multiple second guide rollers 72 are included, and a portion of the second guide rollers 72 are disposed in the second cavity 12. The lithium replenishment device also includes a first vacuum valve 81 for introducing passivating gas into the second cavity 12.

[0149] A lithium replenishment method for an electrode includes the following steps: evacuating the first cavity 11, the second cavity 12, and the third cavity 13; filling the second cavity 12 with passivating gas; controlling the unwinding mechanism 20 and the winding mechanism 30 to pull the substrate 50 to perform vapor deposition on the substrate, and the vapor-deposited substrate 50 enters the second cavity 12 to undergo a passivation reaction with the passivating gas to form a passivation layer on the surface of lithium.

[0150] The passivation gas includes oxygen and an inert gas, with the oxygen content ranging from 30 vol% to 70 vol%. The passivation gas is introduced into the second chamber 12 at a first rate of 0.02 MPa to 0.05 MPa.

[0151] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A lithium replenishment device, characterized in that, include: The housing has a first cavity, a second cavity, a third cavity, a first opening, and a second opening. The first opening connects the first cavity and the second cavity, and the second opening connects the first cavity and the third cavity. The second cavity is used to receive passivation gas. An unwinding mechanism is disposed in the first cavity and is used to place the substrate to be replenished with lithium; A winding mechanism is disposed in the second cavity, the winding mechanism being used to pull the substrate through the first opening and wind up the substrate; A vapor deposition mechanism is disposed in the third cavity, and the vapor deposition mechanism vapor deposits lithium onto the surface of the substrate through the second opening.

2. The lithium replenishment device according to claim 1, characterized in that, It also includes a first partition and a second partition. The first partition is disposed between the first cavity and the second cavity and has the first opening. The second partition is disposed between the first cavity and the third cavity and has the second opening.

3. The lithium replenishment device according to claim 1, characterized in that, The first cavity and the third cavity are arranged sequentially along the first direction.

4. The lithium replenishment device according to claim 1, characterized in that, It also includes multiple guide rollers disposed between the unwinding mechanism and the winding mechanism to guide the substrate transmission.

5. The lithium replenishment device according to claim 4, characterized in that, The guide roller includes a first guide roller, which is disposed on the side of the second opening opposite to the third cavity, and is disposed on the periphery of the second opening.

6. The lithium replenishment device according to claim 4, characterized in that, The guide roller further includes a second guide roller, which is disposed on the transmission path between the second opening and the winding mechanism. The number of the second guide rollers includes a plurality of them, and at least a portion of the plurality of second guide rollers are disposed in the second cavity.

7. The lithium replenishment device according to claim 6, characterized in that, The second cavity includes a first sub-cavity and a second sub-cavity. The winding mechanism is disposed in the first sub-cavity, and at least a portion of the plurality of second guide rollers are disposed in the second sub-cavity. At least one of the first sub-cavity and the second sub-cavity is used to receive passivation gas.

8. The lithium replenishment device according to claim 1, characterized in that, It also includes a first vacuum valve, which is used to introduce passivating gas into the second chamber.

9. The lithium replenishment device according to claim 1, characterized in that, The vapor deposition mechanism includes a vapor deposition element and a baffle. The vapor deposition element is located on the side of the baffle that faces away from the second opening. The baffle includes multiple openings and a shielding portion that surrounds the openings.

10. A battery production system, characterized in that, Includes the lithium replenishment device as described in any one of claims 1 to 9.

11. A method for lithium replenishment of an electrode, characterized in that, include: Vacuum the first, second, and third chambers; The second cavity is filled with passivating gas; The unwinding mechanism and the rewinding mechanism are controlled to pull the substrate to perform vapor deposition on the substrate, and the substrate after vapor deposition enters the second cavity to undergo a passivation reaction with the passivation gas so that a passivation layer is formed on the surface of lithium.

12. The lithium replenishment method according to claim 11, characterized in that, The passivation gas comprises oxygen and an inert gas, wherein the oxygen content is 30 vol% to 70 vol%.

13. The lithium replenishment method according to claim 11, characterized in that, The step of filling the second cavity with passivating gas includes: filling the second cavity with passivating gas at a first rate of 0.02 MPa to 0.05 MPa.

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