Graphitization furnace and battery production system
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-02-28
- Publication Date
- 2026-08-14
Smart Images
Figure CN224635811U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of mechanical engineering technology, and more specifically, to a graphitization furnace and a battery production system. Background Technology
[0002] With the rapid development of new energy technologies, power batteries, due to their high energy density and cycleability, have been widely used in various fields and have become an indispensable part of human life. Currently, carbon materials are widely used as negative electrode materials in power batteries. Among them, graphitized carbon materials (also known as graphite materials) have achieved large-scale commercial application due to their advantages such as long service life, structural stability, and low cost. Furthermore, the excellent properties of graphite materials have also led to their widespread application in multiple fields.
[0003] A graphitization furnace is a device that produces graphite materials. The performance of the products obtained is crucial for the production of graphite and batteries. Therefore, how to improve the performance of the products obtained by graphitization furnaces is a technical problem that urgently needs to be solved. Summary of the Invention
[0004] This application provides a graphitization furnace and a battery production system that can improve the consistency of products obtained from the graphitization furnace.
[0005] In a first aspect, a graphitization furnace is provided, comprising: a furnace body, wherein a material channel is provided in the furnace body; a first electrode, the first electrode extending along a first direction, the first direction being the extension direction of the material channel; and a second electrode, the second electrode having the opposite polarity to the first electrode, wherein a first surface of the first electrode and a second surface of the second electrode are disposed opposite to each other along the first direction.
[0006] In this embodiment, the first and second surfaces are arranged opposite each other along the extension direction of the material channel, so that an electric field is formed between the first and second surfaces. The material is graphitized after being heated by Joule heating through the electric field. At this time, the core heating zone of the graphitization furnace is located in the area opposite the first and second surfaces. That is, the material will pass through the core heating zone of the graphitization furnace, thereby achieving concentrated heating of the material and improving the consistency of the product obtained by using the graphitization furnace.
[0007] In some embodiments, the first electrode is provided with a cavity, at least a portion of which is used to form a first channel segment of the material channel, the outlet of the first channel segment being located on the first surface.
[0008] In this embodiment, a cavity is provided through the first electrode, and the cavity is used to form the first channel section of the material channel, so that the material flowing into the graphitization furnace will pass through the cavity of the first electrode, which increases the probability that the material passes through the relative area between the first surface and the second surface. Based on the electric field existing in the relative area, the material generates Joule heat, that is, the material passes through the core heating zone existing in the relative area, which can concentrate the heating of the material, thereby improving the consistency of the product obtained by using the graphitization furnace.
[0009] In some embodiments, the cavity includes a cylindrical cavity extending along the first direction.
[0010] In this embodiment of the application, by setting the cavity to include a cylindrical cavity, the flowability of the material through the cavity can be improved, so that the heating time of the materials flowing into the graphitization furnace one after another is basically the same, and the heating time of the material is concentrated and uniform, thereby improving the consistency of the products obtained by using the graphitization furnace.
[0011] In some embodiments, the first electrode is a cylindrical structure, and the first surface is the annular end face of the first electrode near the second electrode.
[0012] In this embodiment, by setting the first electrode to a cylindrical structure, it is not only convenient for the preparation and fixing of the first electrode, but also conducive to the uniform flow of materials, so that the heating time of the materials flowing into the graphitization furnace one after another is basically the same, and the heating time of the materials is stable and uniform, thereby improving the consistency of the products obtained by using the graphitization furnace.
[0013] In some embodiments, the ratio of the outer diameter to the inner diameter of the first electrode is 1.3 to 10, and optionally, it is 1.3 to 4.
[0014] In this embodiment, when the ratio of the outer diameter to the inner diameter of the first electrode is too large, the inner diameter will be too small for a given outer diameter, resulting in a small diameter of the cylindrical cavity, a smaller cross-sectional area for material flow, and a smaller amount of material graphitized per unit time, thus reducing the production efficiency of the graphitization furnace. Conversely, when the ratio of the outer diameter to the inner diameter of the first electrode is too small, the thickness of the outer shell of the cylindrical cavity of the first electrode will be smaller, making the first electrode more susceptible to breakage and damage, resulting in lower strength and frequent replacement, which also reduces the production efficiency of the graphitization furnace. By setting the ratio of the outer diameter to the inner diameter of the cylindrical structure of the first electrode within a certain range, the first electrode can have sufficient strength and is less prone to breakage, thus facilitating operations such as moving the first electrode and improving the production efficiency of the graphitization furnace.
[0015] In some embodiments, the second electrode is a cylinder extending along the first direction, and the second surface is the end face of the second electrode near the first electrode.
[0016] In this embodiment of the application, by setting the second electrode as a cylinder, the material can pass through the parallel and uniform electric field formed by the opposite regions of the first and second surfaces. Based on this parallel and uniform electric field, the material generates Joule heat. That is, the material passes through the core heating zone in the opposite region, which can concentrate the heating of the material, thereby improving the consistency of the products obtained by using the graphitization furnace.
[0017] In some embodiments, the outer diameter of the first electrode is less than or equal to the diameter of the second electrode.
[0018] In this embodiment, by setting the outer diameter of the first electrode to be less than or equal to the diameter of the second electrode, the area of the area opposite to the first surface and the second surface is equal to the area of the first surface, thereby forming a large electric field between the first surface and the second surface. When the material passes through this electric field, Joule heat is generated, which can fully heat the material and thus improve the consistency of the product obtained by using the graphitization furnace.
[0019] In some embodiments, the surface of the second electrode facing the first electrode is curved or inclined and tilted away from the material channel inlet.
[0020] In this embodiment, the surface of the second electrode facing the first electrode can be a curved surface or an inclined surface, and it is inclined in the direction away from the material channel inlet. For example, the second surface can be a curved surface or an inclined surface that is high in the middle and low on the outside, so that the material is not easy to accumulate on the second surface, which is beneficial to the flow of the material and the efficiency of material graphitization.
[0021] In some embodiments, the distance between the first surface and the second surface is 500mm to 1200mm.
[0022] In this embodiment, if the distance between the first and second surfaces is too long, the electric field strength between them may decrease, resulting in a smaller current generated in the material under the influence of the electric field and less Joule heat produced. This leads to a lower temperature in the heating zone, preventing the material from being heated in a concentrated manner. Conversely, if the distance between the first and second surfaces is too short, it may cause blockage of the material between them. By setting the distance between the first and second surfaces to any value within the range of 500mm to 1200mm, the production efficiency of the graphitization furnace can be improved while simultaneously heating the material in a concentrated manner.
[0023] In some embodiments, the axis of the first electrode is collinear with the axis of the second electrode.
[0024] In this embodiment, by setting the axis of the first electrode to be collinear with the axis of the second electrode, compared with the two axes not being collinear, the overlapping area of the projection of the first surface and the second surface in the first direction can be increased, thereby increasing the range of the electric field generated in the relative area of the first surface and the second surface. When the material passes through this relative area, Joule heat is generated, which can fully heat the material and thus improve the consistency of the product obtained by using the graphitization furnace.
[0025] In some embodiments, the second electrode has a second channel segment of the material channel formed radially, and the first channel segment and the second channel segment are staggered.
[0026] In this embodiment, by forming a second channel segment offset from the first channel segment in the radial direction of the second electrode, the material can flow through the area opposite the first surface and the second surface, increasing the probability of the material passing through the core heating zone, thereby improving the consistency of the product obtained by using the graphitization furnace.
[0027] In some embodiments, a second channel segment of the material channel is formed on the radially outer side of the second electrode.
[0028] In this embodiment, by forming a second channel segment on the radial outer side of the second electrode, the material flows from the second surface of the second electrode to the second channel segment. The material passes through the electric field formed in the relative area between the first surface and the second surface, i.e., the material passes through the core heating zone, thus achieving concentrated heating of the material and improving the consistency of the products obtained using the graphitization furnace.
[0029] In some embodiments, when the outer diameter of the first electrode is smaller than the diameter of the second electrode, a second channel segment of the material channel is formed in a first region of the second electrode, and the minimum distance of the second channel segment from the axis of the second electrode is greater than the outer diameter of the first electrode.
[0030] In this embodiment, by forming a second channel segment in the first region, the material flows from the second surface of the second electrode to the second channel segment. The material passes through the electric field formed in the relative regions of the first and second surfaces, i.e., the material passes through the core heating zone, thereby achieving concentrated heating of the material and improving the consistency of the products obtained using the graphitization furnace.
[0031] In some embodiments, the first region includes a plurality of through holes extending along the first direction, the through holes forming the second channel segment.
[0032] In this embodiment of the application, by including multiple through holes extending in a first direction to form a second channel segment in the first region, the material can flow along the through holes, thereby improving the material's fluidity and thus improving the production efficiency of the graphitization furnace.
[0033] In some embodiments, the graphitization furnace further includes a plurality of feeding pipes, the plurality of feeding pipes being connected to the second channel section.
[0034] In this embodiment, by connecting multiple feeding pipes to the second channel section, the material can flow from the second channel section to the feeding pipe, thereby reducing the probability of material accumulation in the second channel section and improving the production efficiency of the graphitization furnace.
[0035] In some embodiments, the plurality of discharge pipes are arranged symmetrically with respect to the axis of the material channel.
[0036] In this embodiment, the symmetrical arrangement of multiple feeding pipes improves the fluidity of materials in the material channel, making it less likely for materials to accumulate in the heating zone. The heating time of materials flowing into the material channel sequentially is stable and uniform, thereby improving the consistency of products obtained using the graphitization furnace.
[0037] In some embodiments, a third channel segment of the material channel is formed between the first surface and the second surface, and the third channel segment communicates with the first channel segment and the second channel segment of the material channel.
[0038] In this embodiment, by setting a third channel section, the material is uniformly heated in the third channel section to achieve graphitization, thereby improving the consistency of the products obtained using the graphitization furnace.
[0039] In some embodiments, the first direction is the direction of gravity.
[0040] In this embodiment of the application, by setting the first direction as the gravity direction, the material can flow naturally in the material channel under the action of gravity, without the need for additional power to propel the material flow, thus saving energy.
[0041] In some embodiments, the graphitization furnace further includes a heat insulation element disposed on the side of the first electrode and the second electrode facing the outside of the furnace body.
[0042] In this embodiment, by providing a heat-insulating component, the temperature of the heating zone formed between the first electrode and the second electrode can be kept warm, so that the heating zone is maintained in a high temperature range, the graphitization degree of the material is uniform, and thus the consistency of the products obtained by using the graphitization furnace can be improved.
[0043] In some embodiments, the insulation component includes particles with a diameter of 10 mm to 30 mm.
[0044] In this embodiment of the application, by setting the diameter of the particles included in the insulation component, the insulation effect of the insulation component can be improved at that particle diameter.
[0045] In some embodiments, the thermal conductivity of the insulation component is 0.2 W / mK to 0.5 W / mK.
[0046] In this embodiment of the application, by setting the thermal conductivity of the insulation component, the heat loss of the graphitization furnace can be reduced and the energy utilization rate can be improved under the specified thermal conductivity.
[0047] In some embodiments, the graphitization furnace further includes a heat-resistant element disposed on the side of the heat-insulating element facing the outside of the furnace body.
[0048] In this embodiment of the application, by setting a heat-resistant component, the interior of the furnace can be kept warm, thereby reducing heat loss and improving energy utilization.
[0049] In some embodiments, the heat-resistant component is a cylindrical heat-resistant component and the heat-insulating component is a cylindrical heat-insulating component, wherein the cylindrical heat-resistant component is fitted around the outer periphery of the cylindrical heat-insulating component.
[0050] In this embodiment, the energy loss between the two components is reduced and the energy utilization rate and insulation effect are improved by fitting the cylindrical insulation component and the cylindrical heat insulation component together.
[0051] In a second aspect, a battery production system is provided, the battery production system including the graphitization furnace of the first aspect or any embodiment thereof, the graphitization furnace being used to produce negative electrode graphite material for batteries. Attached Figure Description
[0052] 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 the drawings without creative effort.
[0053] Figure 1 This is a schematic diagram of a graphitization furnace provided in one embodiment of this application;
[0054] Figure 2 This is a schematic diagram of another structure of the graphitization furnace provided in one embodiment of this application;
[0055] Figure 3 This is a schematic diagram of another structure of the graphitization furnace provided in one embodiment of this application;
[0056] Figure 4 This is a schematic diagram of another structure of the graphitization furnace provided in one embodiment of this application;
[0057] Figure 5 This is a schematic diagram of another structure of the graphitization furnace provided in one embodiment of this application;
[0058] Figure 6 This is a schematic diagram of another structure of the graphitization furnace provided in one embodiment of this application;
[0059] Figure 7 This is a schematic diagram of another structure of the graphitization furnace provided in one embodiment of this application;
[0060] Figure 8 This is a top view of a graphitization furnace provided in an embodiment of this application;
[0061] Figure 9 This is a schematic diagram of another structure of the graphitization furnace provided in one embodiment of this application.
[0062] The accompanying drawings are not drawn to scale. Detailed Implementation
[0063] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of this application by way of example, but should not be used to limit the scope of this application, that is, this application is not limited to the described embodiments.
[0064] In the description of this application, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating orientation or positional relationships, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Vertical" is not vertical in the strict sense, but within the allowable tolerance range. "Parallel" is not parallel in the strict sense, but within the allowable tolerance range.
[0065] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of this application. It should also be noted in the description of this application that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0066] 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 three possibilities: A exists, A and B exist simultaneously, and B exists. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.
[0067] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application 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 description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.
[0068] In this application, the reference to "embodiment" means that a specific 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 mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.
[0069] This application relates to a graphitization furnace, which can transform the disordered layer structure of carbon atoms into an ordered graphite crystal structure through heating, thereby achieving the graphitization treatment of non-graphitic carbon. Graphitization aims to improve the thermal and electrical conductivity of carbon materials, enhance their thermal shock resistance and chemical stability, impart lubricity and wear resistance, increase their purity, reduce their hardness, and make them easier to machine, among other things.
[0070] Currently, graphitization furnaces are mainly used for the sintering and graphitization of carbon materials, graphitization of polyimide films (PI), graphitization of thermally conductive materials, sintering of carbon fiber ropes, graphitization of carbon fiber filaments, graphite purification, and high-temperature processing of other materials that can be graphitized in a carbon environment. In some specific applications, graphite materials processed in graphitization furnaces can be used to form negative electrode materials for batteries; for example, graphite is currently a major negative electrode material for lithium batteries.
[0071] Typically, a vertical graphitization furnace includes columnar electrodes located at the top of the furnace body and annular electrodes located in the lower middle part of the furnace body. The columnar electrodes are placed vertically at the center of the material channel, while the annular electrodes are placed horizontally. An umbrella-shaped or frustum-shaped electric field is formed between the lower surface of the columnar electrodes and the side of the annular electrodes. When the material passes through this electric field, it generates Joule heat due to its own resistance, thus forming an umbrella-shaped or frustum-shaped high-temperature region. After passing through this high-temperature region, the material can achieve graphitization. However, due to the uneven distribution of this electric field, the Joule heat generated by the material passing through different regions is uneven. Therefore, this high-temperature region includes a core heating zone that enables complete graphitization of the material and a non-core heating zone with a temperature lower than the core heating zone. The core heating zone is actually located in the area below the lower surface of the columnar electrodes, while the non-core heating zone is located in the area of the material channel other than the core heating zone. As the material flows along the material channel, some of the material will pass through the core heating zone, while another part of the material will pass through the non-core heating zone. This results in uneven graphitization of the other part of the material that passes through the non-core heating zone, and further leads to poor product consistency obtained by using the graphitization furnace.
[0072] In view of this, this application provides a graphitization furnace in which the first surface of the first electrode and the second surface of the second electrode are arranged opposite to each other along the extension direction of the material channel, so that an electric field is formed between the first surface of the first electrode and the second surface of the second electrode. The material is graphitized after being heated by Joule heating by the electric field. At this time, the core heating zone of the graphitization furnace is located in the area opposite to the first surface and the second surface. The material will pass through this opposite area, that is, the material will pass through the core heating zone of the graphitization furnace, thereby realizing the concentrated heating of the material and improving the consistency of the product obtained by using the graphitization furnace.
[0073] In this application, a battery refers to a physical module comprising one or more battery cells to provide electrical energy. A battery generally includes a casing for encapsulating one or more battery cells. Optionally, the battery cell may include a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery, etc., and this application does not limit this. Graphite can be used as the negative electrode active material of the battery cell, and in conjunction with the positive electrode active material of the battery cell (e.g., lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc.) to facilitate the movement of metal ions to form an electric current.
[0074] Figure 1 A front view of a graphitization furnace 100 is shown. (See diagram.) Figure 1 As shown, the main body of the graphitization furnace 100 is arranged vertically, mainly including the furnace body 1 and various functional units arranged in the furnace body 1. Specifically, as... Figure 1 As shown, the graphitization furnace may include a feeding unit, a DC power supply unit, and a cooling and discharging unit.
[0075] The feeding unit mainly includes a hopper 2 and a feed pipe 3. The hopper 2 is located above the furnace body 1, and the hopper 2 is connected to the feed inlet on the furnace body through the feed pipe 3. Optionally, a material shut-off valve 4 can also be installed at the connection between the hopper 2 and the feed pipe 3 to control the flow of material in the material channel 11.
[0076] Optionally, the material entering the graphitization furnace 100 is a graphitizable carbonaceous material, such as petroleum coke, coal coke, and asphalt. After entering the graphitization furnace, the material undergoes four stages: preheating, calcination, graphitization, and cooling to complete the graphitization process and obtain the negative electrode material product. Volatile exhaust gas is released during the process.
[0077] Optionally, the number of hoppers 2 can be two, four, or more, and they are evenly distributed above the furnace body 1.
[0078] The DC power supply unit may include a positive electrode 5, a negative electrode (not shown in the figure), and a DC transformer 6. For example... Figure 1 As shown, the positive electrode 5 can extend into the furnace through the opening at the top of the furnace body 1 and be suspended in the material channel 11, while the negative electrode can be set in the lower middle part of the furnace body 1.
[0079] The DC transformer 6 supplies power to the furnace body 1, with a power output controllable between 600 and 1200 kW. The positive electrode 5 and the negative electrode apply voltage to the material passing between them. DC current flows from the positive terminal of the DC transformer 6 through the material, which releases Joule heat due to its own resistance, maintaining the furnace core temperature above 3000℃, thus creating a stable temperature field between the positive and negative electrodes. The current flowing through the material returns to the negative terminal of the DC transformer 6 from the negative electrode, forming a current flow loop.
[0080] Optionally, the DC power supply unit may further include a fixed brake 7, a conductive element 8, a cable 9, and a copper busbar 10. The positive electrode 5 is held and fixed to the top of the furnace body 1 by the fixed brake 7. The conductive element 8 is fixed below the fixed brake 7, connects to the positive electrode 5 to conduct current, is connected to the copper busbar 10 by the cable 9, and is connected to the positive and negative terminals of the DC transformer 6 by the copper busbar 10.
[0081] Optionally, the positive electrode 5 and the negative electrode can be graphite electrodes.
[0082] The cooling discharge unit is mainly used to cool the graphitized material. Specifically, such as... Figure 1 As shown, the cooling discharge unit may include a low-temperature cooling section 12, which may be a water-cooled jacket. The low-temperature cooling section 12 may also be provided with a water inlet 13 and a water outlet 14, and the cooling medium may be circulating water.
[0083] Optionally, the graphitization furnace 100 may also include a furnace body heating unit (not shown in the figure). For example, a furnace cover and a furnace body lining. The furnace cover may be located on the upper part of the furnace body 1 for heat insulation, while the furnace body lining is arranged around the inner wall of the furnace body 1 to provide heat insulation for the high temperature of the furnace core.
[0084] Figure 2 A schematic diagram of the structure of a graphitization furnace provided in an embodiment of this application is shown. Figure 2 As shown, the graphitization furnace 200 includes a furnace body 210, a first electrode 220, and a second electrode 230. A material channel 211 is provided inside the furnace body 210. The first electrode 220 extends along a first direction, which is the extension direction of the material channel 211. The second electrode 230 has the opposite polarity to the first electrode 220, and the first surface 221 of the first electrode 220 and the second surface 231 of the second electrode 230 are arranged opposite to each other along the first direction.
[0085] It is worth noting that in the embodiments of this application, the first electrode 220 and the second electrode 230 have opposite polarities. For example, the first electrode 220 is the positive electrode and the second electrode 230 is the negative electrode, or vice versa. Thus, an electric field can be formed between the first electrode 220 and the second electrode 230. This electric field can be used to heat the material, thereby achieving the graphitization of the material.
[0086] It is also worth noting that, in the embodiments of this application, the first surface 221 of the first electrode 220 and the second surface 231 of the second electrode 230 are arranged opposite each other along the first direction, which may mean that the projections of the first surface 221 and the second surface 231 in the first direction at least partially overlap. Optionally, the first surface 221 and the second surface 231 may both be planar, or both may both be curved, or one may be planar and the other curved; this application does not limit this. Furthermore, when the first surface 221 and the second surface 231 are both planar, the first surface 221 and the second surface 231 may be arranged in parallel.
[0087] Therefore, by setting the first surface 221 and the second surface 231 opposite each other along the extension direction of the material channel, an electric field is formed between the first surface 221 and the second surface 231. The material is graphitized after being heated by Joule heating through this electric field. At this time, the core heating zone of the graphitization furnace 200 is located in the area opposite the first surface 221 and the second surface 231. That is, the material will pass through the core heating zone of the graphitization furnace 200, thereby achieving concentrated heating of the material and improving the consistency of the product obtained by using the graphitization furnace 200.
[0088] Optionally, if the graphitization furnace 200 is arranged vertically, i.e., the material channel is vertically set, and the material flows along the material channel under the action of gravity, consistent with the natural flow law of objects, then the first electrode 220 extends in the vertical direction, and the first surface 221 and the second surface 231 have an overlapping area in the vertical direction. If the graphitization furnace 200 is arranged horizontally, i.e., the material channel is horizontally set, and the material flows along the material channel in the horizontal direction, then the first electrode 220 extends in the horizontal direction, and the first surface 221 and the second surface 231 have an overlapping area in the horizontal direction. For ease of understanding, the use of terms such as "upper" and "lower" in the following embodiments will be described with the example of a vertical graphitization furnace 200.
[0089] Optionally, the first direction can be the direction of gravity. This allows the material to flow naturally within the material channel under the influence of gravity, eliminating the need for additional power to propel the material and saving energy.
[0090] In the embodiments of this application, such as Figure 3 As shown, the first electrode 220 may be provided with a cavity 222, at least a portion of which is used to form a first channel segment 211a of the material channel 211, the outlet of the first channel segment 211a being located on the first surface 221.
[0091] Optionally, all portions of the cavity 222 may be used to form the first channel segment 211a of the material channel 211, or a portion of the cavity 222 may be used to form the first channel segment 211a of the material channel 211. This application does not limit this.
[0092] It is worth noting that the shape of the cavity 222 can be a regular shape, such as a rectangle, a cylinder, etc., or the shape of the cavity 222 can be an irregular shape, such as the cavity 222 being composed of curved surfaces or planes of uneven size, etc., and this application does not limit this. The cavity 222 can also be curved, and this application does not limit this.
[0093] Therefore, by providing a cavity 222 in the first electrode 220, and using the cavity 222 to form the first channel segment 211a of the material channel 211, the material flowing into the graphitization furnace 200 will pass through the cavity 222 of the first electrode 220, which increases the probability that the material passes through the relative area between the first surface 221 and the second surface 231. Based on the electric field existing in this relative area, the material generates Joule heat, that is, the material passes through the core heating zone existing in this relative area, which can concentrate the heating of the material, thereby improving the consistency of the product obtained by using the graphitization furnace 200.
[0094] In the embodiments of this application, such as Figure 3 As shown, cavity 222 may include a cylindrical cavity extending along a first direction.
[0095] When the cavity 222 includes a cylindrical cavity, the cylindrical cavity can serve as the first channel segment 211a of the material channel 211. The material can flow in from one end of the cylindrical cavity, flow out from the other end of the cylindrical cavity, and then pass through the relative area of the first surface 221 and the second surface 231.
[0096] Therefore, by setting the cavity 222 to include a cylindrical cavity, the flowability of the material through the cavity 222 can be improved, so that the heating time of the materials flowing into the graphitization furnace 200 one after another is basically the same, and the heating time of the material is stable and uniform, thereby improving the consistency of the products obtained by using the graphitization furnace 200.
[0097] In the embodiments of this application, such as Figure 3 As shown, the first electrode 220 can be a cylindrical structure, and the first surface 221 is the annular end face of the first electrode 220 near the second electrode 230.
[0098] Specifically, the first electrode 220 has a cylindrical structure, which can be understood as a cylinder with a through hole on the inner side. The through hole can be used for material flow. That is, the cavity 222 of the first electrode 220 can be a cylindrical cavity. For example, when the graphitization furnace 200 is arranged vertically and the first electrode 220 is located at the top of the furnace body 210, the material can flow into the furnace body 210 through the through hole, that is, the cylindrical cavity.
[0099] Therefore, by setting the first electrode 220 as a cylindrical structure, it is not only convenient for the preparation and fixing of the first electrode 220, but also conducive to the uniform flow of materials, so that the heating time of the materials flowing into the graphitization furnace 200 one after another is basically the same, and the heating time of the materials is stable and uniform, thereby improving the consistency of the products obtained by using the graphitization furnace 200.
[0100] Optionally, when the first electrode 220 is a cylindrical structure, the ratio of its outer diameter to its inner diameter can be 1.3 to 10, or optionally 1.3 to 4. This ratio can take any value within the range, and this value has been obtained through extensive experimental verification. For example, the ratio of the outer diameter to the inner diameter can be 1.3, 2, 3, 4, 5, 6, 7, 8, 9, or 10. This application does not impose any limitation on this.
[0101] When the ratio of the outer diameter to the inner diameter of the first electrode 220 is too large, the inner diameter will be too small for a given outer diameter. This results in a small diameter of the cylindrical cavity, a smaller cross-sectional area for material flow, and a smaller amount of material graphitized per unit time, thus reducing the production efficiency of the graphitization furnace 200. Conversely, if the ratio is too small, the thickness of the outer shell of the cylindrical cavity will be smaller, making the first electrode 220 more susceptible to breakage and damage. This lower strength and frequent replacement of the first electrode 220 also contribute to reduced production efficiency. Therefore, by setting the ratio of the outer diameter to the inner diameter of the cylindrical first electrode 220 within a certain range, the first electrode 220 can be made strong enough to resist breakage, facilitating its movement and improving the production efficiency of the graphitization furnace 200.
[0102] It is worth noting that the first electrode 220 can also be other shapes such as a cuboid with internal through holes, and this application does not limit this.
[0103] In the embodiments of this application, such as Figure 3 As shown, the second electrode 230 can be a cylinder extending along the first direction, and the second surface 231 is the end face of the second electrode 230 near the first electrode 220.
[0104] Specifically, when the second electrode 230 is a cylinder, it can be concentrically arranged with the first electrode 220, which is cylindrical in shape. This allows the material to pass through the through hole of the first electrode 220 and fall onto the second surface 231 of the second electrode 230. The material then flows through the electric field formed by the relative areas of the first surface 221 and the second surface 231, thus achieving concentrated heating. Furthermore, the distribution of the electric field formed is relatively uniform.
[0105] Therefore, by setting the second electrode 230 as a cylinder, the material can pass through the parallel and uniform electric field formed by the opposing regions of the first surface 221 and the second surface 231. Based on this parallel and uniform electric field, the material generates Joule heat. That is, the material passes through the core heating zone that exists in the opposing region, which can concentrate the heating of the material, thereby improving the consistency of the product obtained by using the graphitization furnace 200.
[0106] Optionally, the outer diameter of the first electrode 220 can be less than or equal to the diameter of the second electrode 230. For example, Figure 3 The outer diameter of the first electrode 220 shown is equal to the diameter of the second electrode 230. For example, Figure 4 The outer diameter of the first electrode 220 shown is smaller than the diameter of the second electrode 230.
[0107] Therefore, by setting the outer diameter of the first electrode 220 to be less than or equal to the diameter of the second electrode 230, the area of the area opposite to the first surface 221 and the second surface 231 is equal to the area of the first surface 221, thereby forming a large-scale electric field between the first surface 221 and the second surface 231. When the material passes through this electric field, Joule heat is generated, which can fully heat the material and thus improve the consistency of the product obtained by using the graphitization furnace 200.
[0108] Optionally, the second electrode 230 can also be a regular or irregular shape such as a prism (e.g., a cuboid), a frustum, or a truncated cone, and this application does not limit this.
[0109] Optional, such as Figure 5 As shown, the surface of the second electrode 230 facing the first electrode 220 can be a curved surface or an inclined surface, and it is inclined in the direction away from the inlet of the material channel 211. For example, the second surface 231 can be a curved surface or an inclined surface that is high in the middle and low on the outside, so that the material is less likely to accumulate at the second surface 231, which is beneficial to the flow of the material and the efficiency of material graphitization.
[0110] Optionally, the distance between the first surface 221 and the second surface 231 can be 500mm to 1200mm. For example, it can be 500mm, 600mm, 700mm, 800mm, 900mm, 1000mm or 1100mm, and this application does not limit it.
[0111] If the distance between the first surface 221 and the second surface 231 is too long, the electric field strength between them may decrease, resulting in a smaller current generated in the material under the influence of the electric field and less Joule heat produced. This leads to a lower temperature in the heating zone, preventing the material from being heated in a concentrated manner. Conversely, if the distance between them is too short, the material may become blocked between them. Therefore, by setting the distance between the first surface 221 and the second surface 231 to any value within the range of 500mm to 1200mm, the production efficiency of the graphitization furnace 200 can be improved while simultaneously heating the material in a concentrated manner.
[0112] In this embodiment, the axis of the first electrode 220 is collinear with the axis of the second electrode 230.
[0113] Specifically, the axis of the first electrode 220 and the axis of the second electrode 230 can overlap. Since the first electrode 220 extends along the first direction, its axis is also parallel to the first direction. By setting the axis of the first electrode 220 and the axis of the second electrode 230 to be collinear, compared with the two axes not being collinear, the overlapping area of the projection of the first surface 221 and the second surface 231 in the first direction can be increased, thereby increasing the range of the electric field generated in the relative area of the first surface 221 and the second surface 231. When the material passes through this relative area, Joule heat is generated, which can fully heat the material, thereby improving the consistency of the product obtained by using the graphitization furnace 200.
[0114] In the implementation of this application, if Figure 6 and 7 As shown, the second electrode 230 has a second channel segment 211b of a material channel 211 formed radially, and the first channel segment 211a and the second channel segment 211b are staggered.
[0115] Specifically, the first channel segment 211a and the second channel segment 211b are staggered. After the material flows out of the first channel segment 211a, it passes between the first surface 221 and the second surface 231 and then flows into the second channel segment 211b.
[0116] Therefore, by forming a second channel segment 211b offset from the first channel segment 211a in the radial direction of the second electrode 230, the material can flow through the area opposite to the first surface 221 and the second surface 231, increasing the probability of the material passing through the core heating zone, thereby improving the consistency of the product obtained using the graphitization furnace 200.
[0117] In the embodiments of this application, such as Figure 6 As shown, a second channel segment 211b of a material channel 211 can be formed on the radially outer side of the second electrode 230, for example... Figure 5 The second channel segment shown is the region corresponding to 211b, and the first channel segment formed by the cylindrical cavity 222 of the first electrode 220 is the region corresponding to 211a. The region between the first surface 221 and the second surface 231 can form a third channel segment 211c. The first channel segment 211a and the second channel segment 211b are connected through the third channel segment 211c.
[0118] Therefore, by forming a second channel segment 211b on the radially outer side of the second electrode 230, the material flows from the second surface 231 of the second electrode 230 to the second channel segment 211b. The material passes through the electric field formed in the relative area between the first surface 221 and the second surface 231, that is, the material passes through the core heating zone, thus achieving concentrated heating of the material and improving the consistency of the product obtained using the graphitization furnace 200.
[0119] In the embodiments of this application, such as Figure 7 As shown, when the outer diameter of the first electrode 220 is smaller than the diameter of the second electrode 230, a second channel segment 211b of a material channel is formed in the first region 232 of the second electrode 230. The minimum distance of the second channel segment 211b from the axis of the second electrode 230 is greater than the outer diameter of the first electrode 220.
[0120] Specifically, the minimum distance of the second channel segment 211b from the axis of the second electrode 230 is greater than the outer diameter of the first electrode 220. This can be understood as the shortest distance of each point in the second channel segment 211b from the axis of the second electrode 230 being greater than the outer diameter of the first electrode 220.
[0121] Therefore, by forming a second channel segment 211b in the first region 232, the material flows from the second surface 231 of the second electrode 230 to the second channel segment 211b. The material passes through the electric field formed in the relative regions of the first surface 221 and the second surface 231, that is, the material passes through the core heating zone, thereby achieving concentrated heating of the material and improving the consistency of the products obtained using the graphitization furnace 200.
[0122] Optional, such as Figure 7 As shown, the first region 232 includes a plurality of through holes 232a extending along a first direction, the through holes 232a forming a second channel segment 211b. For example, Figure 6 The second channel segment 211b shown includes a through hole 232a in the region corresponding to 211b, and the cylindrical cavity 222 of the first electrode 220 forms the first channel segment 211a, while a third channel segment 211c can be formed between the first surface 221 and the second surface 231. The first channel segment 211a and the second channel segment 211b are connected through the third channel segment 211c.
[0123] Therefore, by including a plurality of through holes 232a extending in a first direction in the first region 232 to form a second channel segment 211b, the material can flow along the through holes 232a, thereby improving the material flowability and thus improving the production efficiency of the graphitization furnace.
[0124] In the embodiments of this application, such as Figure 6 As shown in Figure 7, the graphitization furnace 200 may also include: a plurality of feeding pipes 240, which are connected to the second channel section 211b.
[0125] Therefore, by connecting multiple feeding pipes 240 with the second channel section 211b, the material can flow from the second channel section 211b to the feeding pipe, thereby reducing the probability of material accumulation in the second channel section 211b and improving the production efficiency of the graphitization furnace 200.
[0126] In the embodiments of this application, such as Figure 8 As shown, multiple discharge pipes 240 can be arranged symmetrically with respect to the axis of the material channel 211.
[0127] Specifically, the multiple discharge pipes 240 can be arranged symmetrically about the axis of the material channel 211. For example, they can be... Figure 8 As shown, a discharge pipe 240 is provided at radial intervals of 90 degrees along the material channel 211, and four discharge pipes 240 can be symmetrically arranged. Alternatively, a discharge pipe 240 can be provided at radial intervals of 30 degrees or 60 degrees along the material channel 211. This application does not limit the number of discharge pipes 240.
[0128] Therefore, by symmetrically arranging multiple feeding pipes 240, the flowability of materials in the material channel 211 is improved, materials are less likely to accumulate in the heating zone, and the heating time of materials flowing into the material channel 211 one after another is stable and uniform, thereby improving the consistency of products obtained by using the graphitization furnace 200.
[0129] It is understood that in some other embodiments, the second channel section 211b can also be connected via an annular discharge pipe.
[0130] In this embodiment of the application, a third channel segment 211c of a material channel 211 is formed between the first surface 221 and the second surface 231, and the third channel segment 211c is connected to the first channel segment 211a and the second channel segment 211b of the material channel 211.
[0131] Specifically, such as Figure 6 and 7As shown, a third channel segment 211c can be formed in the region corresponding to 211c, a first channel segment 211a can be formed in the region corresponding to 211a, and a second channel segment 211b can be formed in the region corresponding to 211b. The third channel segment 211c is connected to the first channel segment 211a and the second channel segment 211b. Alternatively, the third channel segment 211c is located between the first channel segment 211a and the second channel segment 211b.
[0132] Therefore, by setting up a third channel section 211c, the material is uniformly heated in the third channel section 211c to achieve graphitization of the material, thereby improving the consistency of the products obtained using the graphitization furnace 200.
[0133] It is worth noting that in some embodiments, both the first electrode 220 and the second electrode 230 can be graphite electrodes.
[0134] It is also worth noting that the current density of the first electrode 220 and / or the second electrode 230 can be 15 A / cm². 2 ~30A / cm 2 The current load can be 30000A to 50000A, and the resistivity can be less than 5μΩm.
[0135] In the embodiments of this application, such as Figure 9 As shown, the graphitization furnace 200 may further include: a heat insulation element 250, disposed on the side of the first electrode 220 and the second electrode 230 facing the outside of the furnace body 210.
[0136] Specifically, Figure 9 The dotted shaded areas shown represent the insulation component 250, which can be arranged around the outer periphery of the first electrode 220 and the second electrode 230 to keep the temperature of the heating zone formed between the first electrode 220 and the second electrode 230, so that the heating zone is maintained in a high temperature range, the graphitization degree of the material is uniform, and the consistency of the products obtained by using the graphitization furnace 200 can be improved.
[0137] Optionally, the diameter of the particles included in the insulation component 250 can be 10mm to 30mm. Larger particle diameters result in better insulation performance.
[0138] Optionally, the thermal conductivity of the insulation component 250 is 0.2 W / mK to 0.5 W / mK. The low thermal conductivity reduces heat loss from the graphitization furnace, thereby improving energy utilization.
[0139] In the embodiments of this application, such as Figure 9 As shown, the graphitization furnace 200 may also include a heat-resistant component 260 disposed on the side of the heat-insulating component 250 facing the outside of the furnace body 210.
[0140] Specifically, Figure 9 The shaded area shown represents the heat-resistant component 260. The heat-resistant component 260 can be arranged around the outer periphery of the insulation component 250 to insulate the interior of the furnace body 210, thereby reducing heat loss and improving energy utilization.
[0141] Optionally, the heat-resistant component 260 is a cylindrical heat-resistant component and the insulation component 250 is a cylindrical insulation component, with the cylindrical heat-resistant component fitting around the outer periphery of the cylindrical insulation component.
[0142] Therefore, by combining cylindrical insulation components with cylindrical heat insulation components, energy loss between the two components is reduced, and energy utilization and insulation effect are improved.
[0143] In some embodiments, the heat-resistant component 260 has a low thermal conductivity and good insulation properties, which can extend the service life of the graphitization furnace 200.
[0144] Optionally, the heat resistance temperature of the heat-resistant component 260 can be 1450℃~2600℃.
[0145] This application also provides a battery production system, including the graphitization furnace 200 in any of the above embodiments, the graphitization furnace 200 being used to produce negative electrode graphite material for batteries.
[0146] It is understandable that, in addition to the graphitization furnace 200 for producing the negative electrode graphite material for batteries, the battery production system may also include related equipment for producing other battery materials.
[0147] The battery production system can be a battery production line, in which multiple devices can be located in the same centralized location, or in separate locations.
[0148] It should be noted that only some structures of the graphitization furnace 200 are listed in the above embodiments of this application. In addition to the structures involved in the above embodiments, the graphitization furnace 200 of this application may also include other system structures of graphitization furnaces in related technologies, such as feeding system, discharging system, electrical system of electrodes, electrode clamping system, exhaust treatment system, etc. The relevant technical solutions of each system can be found in the specific descriptions in related technologies, and will not be discussed in detail here.
[0149] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. 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 graphitization furnace characterized by, include: Furnace body (210), wherein a material channel (211) is provided inside the furnace body (210); A first electrode (220) extends along a first direction, which is the extension direction of the material channel (211). The first electrode (220) is provided with a cavity (222), at least a portion of which is used to form a first channel segment (211a) of the material channel (211). The second electrode (230) has the opposite polarity to the first electrode (220). The first surface (221) of the first electrode (220) and the second surface (231) of the second electrode (230) are arranged opposite to each other along the first direction. The second electrode (230) has a second channel segment (211b) of the material channel (211) formed radially. The outlet of the first channel segment (211a) is located on the first surface (221). The first channel segment (211a) and the second channel segment (211b) are staggered. Multiple discharge pipes (240) are connected to the second channel section (211b).
2. The graphitization furnace of claim 1, wherein, The cavity (222) includes a cylindrical cavity extending along the first direction.
3. The graphitization furnace according to claim 1 or 2, characterized in that, The first electrode (220) has a cylindrical structure, and the first surface (221) is the annular end face of the first electrode (220) near the second electrode (230).
4. The graphitization furnace of claim 3, wherein The ratio of the outer diameter to the inner diameter of the first electrode (220) is 1.3 to 10, and optionally 1.3 to 4.
5. The graphitization furnace of claim 3, wherein The second electrode (230) is a cylinder extending along the first direction, and the second surface (231) is the end face of the second electrode (230) near the first electrode (220).
6. The graphitization furnace of claim 5, wherein, The outer diameter of the first electrode (220) is less than or equal to the diameter of the second electrode (230).
7. The graphitization furnace of claim 1, wherein The surface of the second electrode (230) facing the first electrode (220) is curved or inclined and tilted away from the inlet of the material channel (211).
8. The graphitization furnace of claim 1, wherein, The distance between the first surface (221) and the second surface (231) is 500mm~1200mm.
9. The graphitization furnace according to claim 1, characterized in that, The axis of the first electrode (220) is collinear with the axis of the second electrode (230).
10. The graphitization furnace of claim 1, wherein, The second channel segment (211b) is formed on the radially outer side of the second electrode (230).
11. The graphitization furnace of claim 1, wherein, When the outer diameter of the first electrode (220) is smaller than the diameter of the second electrode (230), the first region (232) of the second electrode (230) is formed with the second channel segment (211b), and the minimum distance of the second channel segment (211b) from the axis of the second electrode (230) is greater than the outer diameter of the first electrode (220).
12. The graphitization furnace of claim 11, wherein, The first region (232) includes a plurality of through holes (232a) extending along the first direction, the through holes forming the second channel segment (211b).
13. The graphitization furnace of claim 1, wherein, The plurality of discharge pipes (240) are arranged symmetrically with respect to the axis of the material channel (211).
14. The graphitization furnace of claim 1, wherein, A third channel segment (211c) of the material channel (211) is formed between the first surface (221) and the second surface (231), and the third channel segment (211c) is connected to the first channel segment (211a) and the second channel segment (211b) of the material channel (211).
15. The graphitization furnace of claim 1, wherein, The first direction is the direction of gravity.
16. The graphitization furnace of claim 1, wherein, The graphitization furnace further includes a heat insulation component (250), disposed on the side of the first electrode (220) and the second electrode (230) facing the outside of the furnace body (210).
17. The graphitization furnace of claim 16, wherein, The insulation component (250) includes particles with a diameter of 10mm to 30mm.
18. The graphitization furnace of claim 16, wherein, The thermal conductivity of the insulation component (250) is 0.2W / mK to 0.5W / mK.
19. The graphitization furnace of claim 16, wherein, The graphitization furnace further includes a heat-resistant component (260), disposed on the side of the heat-insulating component (250) facing the outside of the furnace body (210).
20. The graphitization furnace of claim 19, wherein, The heat-resistant component (260) is a cylindrical heat-resistant component and the heat-insulating component (250) is a cylindrical heat-insulating component, and the cylindrical heat-resistant component is fitted around the outer periphery of the cylindrical heat-insulating component.
21. A battery production system characterized by comprising: include: The graphitization furnace according to any one of claims 1-20, wherein the graphitization furnace is used to produce negative electrode graphite material for batteries.