Graphitization furnace and battery production equipment

Abstract

The invention provides a graphitization furnace and battery production equipment. The performance of the graphitization furnace can be improved, and the service life of the graphitization furnace can be prolonged. The graphitization furnace comprises a furnace body, wherein a material channel is arranged in the furnace body; the first electrode extends in the first direction, at least part of the first electrode is arranged in the material channel, and the first direction is the extending direction of the material channel; the polarity of the second electrode is opposite to that of the first electrode; the second electrode comprises a second substrate and a waterproof layer; one end of the second substrate is positioned in the material channel and is spaced from the first electrode, and the other end extends out of the side wall of the furnace body; the waterproof layer is arranged on the surface of the part, extending out of the furnace body, of the second base body.

Description

Technical Field

[0001] The present application relates to the technical field of battery production equipment, and in particular to a graphitization furnace and battery production equipment. Background Art

[0002] In recent years, as the application scope of battery technology has become wider and wider, batteries are widely used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, as well as in many fields such as power tools, electric bicycles, electric motorcycles and electric vehicles.

[0003] At present, carbon materials are widely used in negative electrode materials of batteries. Among them, graphitized carbon materials (also referred to as graphite materials) have been widely used in commercial applications due to their long service life, stable structure and low cost. Graphitization furnace is a kind of equipment that can generate graphite materials. Its performance and life are very important for the production and manufacturing of graphite and batteries.

[0004] In view of this, how to improve the performance and life of the graphitization furnace is a technical problem that needs to be solved urgently. Summary of the invention

[0005] The present application is made in view of the above-mentioned problems, and one of its purposes is to provide a graphitization furnace and a battery production device, which can improve the performance and life of the graphitization furnace.

[0006] In order to achieve the above object, the first aspect of the present application provides a graphitization furnace, comprising:

[0007] A furnace body, wherein a material channel is arranged in the furnace body;

[0008] a first electrode extending along a first direction and at least partially disposed in the material channel, wherein the first direction is an extending direction of the material channel;

[0009] The second electrode has a polarity opposite to that of the first electrode; the second electrode includes a second substrate and a waterproof layer; one end of the second substrate is located in the material channel and is spaced apart from the first electrode, and the other end extends to the outside of the side wall of the furnace body; the waterproof layer is provided on the surface of the portion of the second substrate extending out of the furnace body.

[0010] By providing a waterproof layer on the surface of the part of the second substrate of the second electrode that extends out of the furnace body, in the process of spraying water to cool down the part of the second substrate that extends out of the furnace body, the waterproof layer can effectively prevent water from entering the furnace body through the holes in the second substrate, reducing or avoiding the impact of water entering the furnace body on the product indicators of the graphite material, as well as the etching of the negative electrode by water; and it can also play a role in isolating the air, reducing the direct contact between the second substrate and the air, and alleviating the oxidation of the second substrate. By providing the above-mentioned waterproof layer, the performance and service life of the graphitization furnace can be effectively improved.

[0011] In any embodiment, the material of the waterproof layer includes one or more of an inorganic hydrophobic material and an organic hydrophobic resin, so as to achieve a good waterproof effect and effectively prevent water from entering the furnace body through the pores in the second substrate during the spray cooling process.

[0012] In any embodiment, the inorganic hydrophobic material includes one or more of aluminum nitride, boron nitride, beryllium oxide, silicon nitride and silicon carbide, which is beneficial to improve the waterproof performance and scour resistance of the waterproof layer.

[0013] In any embodiment, the organic hydrophobic resin includes one or more of phenolic resin, epoxy resin, bismaleimide resin, vinyl resin and cyanate resin, which is beneficial to improve the waterproof performance of the waterproof layer.

[0014] In any embodiment, the thickness of the waterproof layer is 10 μm to 100 μm, which is conducive to making the waterproof layer have good waterproof performance and having a good waterproof effect on the portion of the second substrate extending out of the furnace body.

[0015] In any embodiment, the waterproof layer is rotated 8000 to 10000 times under the conditions of 23±2°C and relative humidity of 50±5%. In this way, the waterproof layer has good scouring resistance, which is conducive to making the waterproof layer better resist water scouring during the spray cooling process, and further improving the service life of the second electrode and the graphitization furnace.

[0016] In any embodiment, the thermal conductivity of the waterproof layer is 0.5W / (m·k) to 20W / (m·k). In this way, the heat of the second substrate can be conducted out to cool it down, and excessive heat loss in the furnace can be avoided.

[0017] In any embodiment, the second electrode further comprises a heat-conducting layer, which is disposed on the surface of the portion of the second substrate extending out of the furnace body and is located between the second substrate and the waterproof layer. This is more conducive to conducting away the heat of the portion of the second substrate extending out of the furnace body and spraying and cooling the portion.

[0018] In any embodiment, the material of the heat-conducting layer includes one or more of heat-conducting glue, heat-conducting silicone grease and heat-conducting ceramics. In this way, the heat-conducting layer can have good thermal conductivity, which is conducive to effectively conducting away the heat of the part of the second substrate extending out of the furnace body, and also has good temperature resistance, can withstand higher temperatures, and improve the durability of the waterproof layer and the heat-conducting layer.

[0019] In any embodiment, the thickness ratio of the heat conductive layer to the waterproof layer is 1:1 to 10. This is conducive to achieving a good waterproof effect and spray cooling effect, which is conducive to improving the service life of the second electrode and improving the performance and life of the graphitization furnace.

[0020] In any embodiment, the thickness ratio of the heat conductive layer to the waterproof layer is 1:1-2.5.

[0021] In any embodiment, the thickness of the heat-conducting layer is 5 μm to 30 μm. This is conducive to the heat dissipation of the portion of the second substrate extending out of the furnace body, and has a good spray cooling effect on the portion of the second substrate extending out of the furnace body.

[0022] In any embodiment, the ratio of thermal conductivity of the heat-conducting layer to the waterproof layer is 1 to 50: 1. This is conducive to better cooling the portion of the second substrate extending out of the furnace body.

[0023] In any embodiment, the ratio of the thermal conductivity of the heat conductive layer to the thermal conductivity of the waterproof layer is 2 to 15: 1. In this way, while effectively cooling the portion of the second substrate extending out of the furnace body, it is helpful to avoid excessive heat loss in the furnace body.

[0024] In any embodiment, the thermal conductivity of the heat-conducting layer is 2W / (m·k) to 50W / (m·k). This is more conducive to extracting the heat of the portion of the second substrate extending out of the furnace body, and is conducive to effectively cooling the portion of the second substrate extending out of the furnace body.

[0025] In any embodiment, the thermal conductive layer is subjected to abrasion at 23±2° C. and a relative humidity of 50±5% for a number of rotations of 6000 to 8000. Thus, the thermal conductive layer has good wear resistance.

[0026] In any embodiment, the second base body extends in a radial direction of the material channel.

[0027] In any embodiment, the number of the second electrodes is multiple, and the multiple second electrodes are arranged at intervals along the circumference of the material channel. This is conducive to making the electric field distribution in the cross section of the material channel more uniform, and is conducive to improving the uniformity of graphitization of the material.

[0028] In any embodiment, the first electrode is a positive electrode, and the second electrode is a negative electrode.

[0029] The second aspect of the present application provides a battery production device, comprising the graphitization furnace of the first aspect of the present application, wherein the graphitization furnace is used to produce graphite materials for batteries.

[0030] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to better describe and illustrate the embodiments or examples provided by the present application, reference may be made to one or more drawings. The additional details or examples used to describe the drawings should not be considered as limiting the scope of the disclosed application, the embodiments or examples currently described, and any of the best modes of these applications currently understood. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0032] Figure 1 This is a schematic structural diagram of a graphitization furnace according to one embodiment of the present application;

[0033] Figure 2 This is an enlarged view of the structure of the second electrode in the graphitization furnace according to one embodiment of the present application.

[0034] Description of reference numerals:

[0035] 100. Graphitization furnace; 110. Furnace body; 111. Material channel; 120. First electrode; 130. Second electrode; 131. Second substrate; 132. Waterproof layer; 133. Heat conductive layer; 140. Power supply; 151. Material silo; 152. Material pipe; 153. Material shut-off valve; 160. Tail gas treatment unit; 170. Cooling and discharging unit. DETAILED DESCRIPTION

[0036] The following embodiments of the technical solution of the present application will be described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0038] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0039] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0040] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0041] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0042] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0043] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0044] The "range" disclosed in the present application can be defined in the form of a lower limit and an upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a special range. The range defined in this way can be inclusive or exclusive of end values, and any end value can be independently included or not included, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 60 to 120 and 80 to 110 is listed for a specific parameter, it is understood that the range of 60 to 110 and 80 to 120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are also listed, the following ranges can all be expected: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4 and 2 to 5. In the present application, unless otherwise specified, the numerical range "0 to 5" means that all real numbers between "0 to 5" have been fully listed herein, and "0 to 5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to listing the parameter as, for example, integers 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc. For example, when a parameter is expressed as an integer selected from "2 to 10", it is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9 and 10.

[0045] In the present application, in the open technical features or technical solutions described by the words "contain", "include", "comprise", etc., unless otherwise specified, additional members other than the listed members are not excluded, and it can be regarded as providing both closed features or solutions consisting of the listed members and open features or solutions including additional members in addition to the listed members. For example, A includes a1, a2 and a3. Unless otherwise specified, it may also include other members or may not include additional members. It can be regarded as providing both the feature or solution of "A consists of a1, a2 and a3" and the feature or solution of "A not only includes a1, a2 and a3, but also includes other members". In the present application, unless otherwise specified, A (such as B) means that B is a non-limiting example of A, and it can be understood that A is not limited to B.

[0046] In this application, "optionally", "optional", and "optional" mean optional, that is, any one of the two parallel schemes of "yes" or "no". If there are multiple "options" in a technical solution, unless otherwise specified and there is no contradiction or mutual restriction, each "option" is independent.

[0047] At present, carbon materials are widely used in negative electrode materials of batteries, among which graphitized carbon materials have been widely used in commercial applications due to their advantages such as long service life, stable structure and low cost. As a device that can generate graphite materials, the performance and life of the graphitization furnace are extremely important for the production and manufacturing of graphite and batteries.

[0048] In the production process of the continuous graphitization furnace, the positive electrode is inserted from the material feed end into the core temperature zone in the material channel of the furnace body, and the negative electrode is inserted into the material channel from the side of the furnace body. The positive electrode is spaced from the negative electrode, and an electric field is generated in the material channel after power is turned on. When the material in the material channel passes through the electric field, Joule heat will be generated due to its own resistance, thereby forming a high-temperature area. After passing through the high-temperature area, the material can be graphitized.

[0049] During the production process of the graphitization furnace, one end of the negative electrode needs to extend out of the furnace body and connect to the power supply to achieve conduction, while the other end extends into the material channel, close to the core temperature zone of the material channel, so the overall temperature of the negative electrode is relatively high. The part of the negative electrode extending out of the furnace body is exposed to the air and is easily oxidized at high temperatures, so it needs to be cooled. Water is usually used to spray and cool the part of the negative electrode extending out of the furnace body.

[0050] However, since the negative electrode is usually made of graphite material, which is a porous structure, water will enter the furnace through the pores in the negative electrode during the spray cooling process, affecting the product indicators of the graphite material. In addition, the water entering the furnace will react with the negative electrode at a higher temperature, causing etching of the negative electrode, thereby affecting the service life of the negative electrode and the graphitization furnace.

[0051] For this, see Figure 1 and Figure 2In one embodiment of the present application, a graphitization furnace 100 is provided, which includes a furnace body 110, a first electrode 120, and a second electrode 130. A material channel 111 is provided in the furnace body 110, and the material channel 111 extends from the upper part to the lower part of the furnace body 110; the first electrode 120 extends along a first direction and is at least partially provided in the material channel 111, and the first direction is the extension direction of the material channel 111; the second electrode 130 has an opposite polarity to the first electrode 120; the second electrode 130 includes a second substrate 131 and a waterproof layer 132, one end of the second substrate 131 is located in the material channel 111 and is spaced from the first electrode 120, and the other end thereof extends to the outside of the side wall of the furnace body 110; the waterproof layer 132 is provided on the surface of the portion of the second substrate 131 extending out of the furnace body 110.

[0052] The above-mentioned graphitization furnace 100 of the present application, by providing a waterproof layer 132 on the surface of the part of the second substrate 131 extending out of the furnace body 110, in the process of spraying and cooling the part of the second substrate 131 extending out of the furnace body 110 with water, the waterproof layer 132 can effectively prevent water from entering the interior of the furnace body 110 through the pores in the second substrate 131, reducing or avoiding the impact of water entering the furnace body 110 on the product index of the graphite material, and the etching of the negative electrode by water; and can play the role of isolating the air, reducing the direct contact between the second substrate 131 and the air, and relieving the oxidation of the second substrate 131. By providing the above-mentioned waterproof layer 132, the performance and service life of the graphitization furnace 100 can be effectively improved.

[0053] It should be noted that the first electrode 120 is a positive electrode and the second electrode 130 is a negative electrode. The first electrode 120 and the second substrate 131 of the second electrode 130 can both be graphite electrodes. The graphitization furnace 100 also includes a power supply 140, and the first electrode 120 and the second electrode 130 are respectively connected to the positive electrode and the negative electrode of the power supply 140. If the graphitization furnace 100 is arranged in a vertical manner, that is, the material channel 111 is arranged vertically, the material flows downward along the material channel 111 under the action of gravity, which is consistent with the natural flow law of the object, then the first electrode 120 extends in the vertical direction. If the graphitization furnace 100 is arranged in a horizontal manner, that is, the material channel is arranged horizontally, and the material flows along the material channel 111 in the horizontal direction, then the first electrode 120 extends in the horizontal direction. Figure 1 The middle part is a vertical graphitization furnace 100, and the extension direction of the material channel 111 in the graphitization furnace 100 is a vertical direction.

[0054] In some embodiments, the material of the waterproof layer 132 includes one or more of an inorganic hydrophobic material and an organic hydrophobic resin. By using an inorganic hydrophobic material and / or an organic hydrophobic resin as the material of the waterproof layer 132, a good waterproof effect can be achieved, effectively preventing water in the spray cooling process from entering the interior of the furnace body 110 through the pores in the second substrate 131.

[0055] Optionally, the inorganic hydrophobic material includes one or more of aluminum nitride, boron nitride, beryllium oxide, silicon nitride and silicon carbide; the organic hydrophobic resin includes one or more of phenolic resin, epoxy resin, bismaleimide resin, vinyl resin and cyanate resin. Using the above materials as the material of the waterproof layer 132 can not only play a good waterproof role, but also make the waterproof layer 132 have good scour resistance. The waterproof layer 132 can be prepared by solution coating method, or by chemical vapor deposition, physical vapor deposition and other methods.

[0056] In some embodiments, the thickness of the waterproof layer 132 is 10 μm to 100 μm. Controlling the thickness of the waterproof layer 132 within the above-mentioned thickness range is conducive to making the waterproof layer 132 have good waterproof performance, and having a good waterproof effect on the portion of the second substrate 131 extending out of the furnace body 110. It can be understood that the thickness of the waterproof layer 132 can be 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, 100 μm, and any value within the range formed by any two of the above values.

[0057] In some embodiments, the waterproof layer 132 is rotated 8000 to 10000 times at 23±2°C and 50±5% relative humidity. In this way, the waterproof layer 132 has good scouring resistance, which is beneficial for the waterproof layer 132 to better resist water scouring during the spray cooling process, and further improve the service life of the second electrode 130.

[0058] In some embodiments, the thermal conductivity of the waterproof layer 132 is 0.5W / (m·k) to 20W / (m·k). Controlling the thermal conductivity of the waterproof layer 132 within the above range can not only conduct heat from the second substrate 131 to reduce the temperature, but also avoid excessive heat loss in the furnace body 110. It can be understood that the thermal conductivity of the waterproof layer 132 can be 0.5W / (m·k), 0.8W / (m·k), 1W / (m·k), 2W / (m·k), 3W / (m·k), 4W / (m·k), 5W / (m·k), 6W / (m·k), 7W / (m·k), 8W / (m·k), 9W / (m·k), 10W / (m·k), 11W / (m·k), 12W / (m·k), 13W / (m·k), 14W / (m·k), 15W / (m·k), 16W / (m·k), 17W / (m·k), 18W / (m·k), 19W / (m·k), 20W / (m·k) and any value within the range formed by any two of the above values.

[0059] In some embodiments, the second electrode 130 further includes a heat-conducting layer 133, which is disposed on the surface of the portion of the second substrate 131 extending out of the furnace body 110 and between the second substrate 131 and the waterproof layer 132. By disposing the heat-conducting layer 133 between the surface of the portion of the second substrate 131 extending out of the furnace body 110 and the waterproof layer 132, it is beneficial to conduct heat from the portion of the second substrate 131 extending out of the furnace body 110, and spray and cool down the portion.

[0060] In some specific examples, the material of the heat-conducting layer 133 includes one or more of heat-conducting glue, heat-conducting silicone grease and heat-conducting ceramics. Among them, the main component of the heat-conducting glue can be a vinyl polysiloxane mixture; the heat-conducting ceramic can be some high-performance heat-conducting ceramics such as alumina ceramics. Using the above materials as the heat-conducting layer 133 can make the heat-conducting layer 133 have good thermal conductivity, can effectively conduct away the heat of the part of the second substrate 131 extending out of the furnace body 110, and also have good temperature resistance, can withstand higher temperatures, and improve the durability of the waterproof layer 132 and the heat-conducting layer 133. The heat-conducting layer 133 can be prepared by a solution coating method, or by chemical vapor deposition, physical vapor deposition and other methods.

[0061] In some embodiments, the thickness ratio of the heat conductive layer 133 to the waterproof layer 132 is 1:1 to 10. Thus, setting the thickness of the waterproof layer 132 to be equal to that of the heat conductive layer 133, or thicker than the heat conductive layer 133, is conducive to achieving a good waterproof effect and a spray cooling effect, which is conducive to improving the service life of the second electrode 130 and improving the performance and life of the graphitization furnace 100.

[0062] It is understandable that the thickness ratio of the heat conductive layer 133 to the waterproof layer 132 may be 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, and any ratio within the range formed by any two of the above ratios.

[0063] Further optionally, the thickness ratio of the heat conductive layer 133 to the waterproof layer 132 is 1:1-2.5.

[0064] In some embodiments, the thickness of the heat-conducting layer 133 is 5 μm to 30 μm. Controlling the thickness of the heat-conducting layer 133 within the above range is conducive to extracting the heat of the portion of the second substrate 131 extending out of the furnace body 110, and has a good spray cooling effect on the portion of the second substrate 131 extending out of the furnace body 110. It can be understood that the thickness of the heat-conducting layer 133 can be 5 μm, 8 μm, 10 μm, 12 μm, 14 μm, 16 μm, 18 μm, 20 μm, 22 μm, 24 μm, 26 μm, 28 μm, 30 μm, and any value within the range formed by any two of the above values.

[0065] In some embodiments, the thermal conductivity ratio of the heat conductive layer 133 to the waterproof layer 132 is 1 to 50:1. Controlling the thermal conductivity ratio of the heat conductive layer 133 to the waterproof layer 132 within the above range is conducive to better cooling the portion of the second substrate 131 extending out of the furnace body 110. It is understandable that the thermal conductivity ratio of the heat conductive layer 133 to the waterproof layer 132 can be 1:1, 5:1, 8:1, 10:1, 12:1, 15:1, 18:1, 20:1, 22:1, 25:1, 28:1, 30:1, 32:1, 35:1, 38:1, 40:1, 42:1, 45:1, 48:1, 50:1 and any ratio within the range formed by any two of the above ratios.

[0066] Further optionally, the thermal conductivity ratio of the heat conductive layer 133 to the waterproof layer 132 is 2 to 15: 1. Controlling the thermal conductivity ratio of the heat conductive layer 133 to the waterproof layer 132 within the above range can effectively cool the portion of the second substrate 131 extending out of the furnace body 110 while preventing excessive heat loss in the furnace body 110.

[0067] In some embodiments, the thermal conductivity of the heat-conducting layer 133 is 2W / (m·k) to 50W / (m·k). Controlling the thermal conductivity of the heat-conducting layer 133 within the above range is more conducive to extracting the heat of the portion of the second substrate 131 extending out of the furnace body 110, and is conducive to effectively cooling the portion of the second substrate 131 extending out of the furnace body 110. It can be understood that the thermal conductivity of the thermal conductive layer 133 may be 2 W / (m·k), 5 W / (m·k), 10 W / (m·k), 12 W / (m·k), 15 W / (m·k), 18 W / (m·k), 20 W / (m·k), 22 W / (m·k), 25 W / (m·k), 28 W / (m·k), 30 W / (m·k), 32 W / (m·k), 35 W / (m·k), 38 W / (m·k), 40 W / (m·k), 42 W / (m·k), 45 W / (m·k), 48 W / (m·k), 50 W / (m·k) and any value within the range formed by any two of the above values.

[0068] In some embodiments, the thermal conductive layer 133 is rubbed for 6000 to 8000 revolutions at 23±2° C. and 50±5% relative humidity. Thus, the thermal conductive layer 133 has good wear resistance and can better maintain the integrity of the coating on the second substrate 131 .

[0069] See also Figure 2 In some embodiments, the ratio of the length a of the second substrate 131 extending out of the furnace body 110 to the length b of the second substrate 131 is 1:2-5. That is, the ratio of the length of the second substrate 131 provided with the waterproof layer 132 and the heat conductive layer 133 outside the furnace body 110 to the overall length of the second substrate 131 is 1:2-5. The specific ratio can be set according to the actual needs of different graphitization furnaces 100.

[0070] In some embodiments, the second substrate 131 extends radially along the material channel 111; there are multiple second electrodes 130, and the multiple second electrodes 130 are arranged at intervals along the circumferential direction of the material channel 111. In this way, the electric field distribution in the cross section of the material channel 111 is more uniform, which is conducive to improving the uniformity of graphitization of the material. It can be understood that the circumferential direction refers to the circumferential direction of the material channel 111.

[0071] In some embodiments, the second electrode 130 is disposed in the middle and lower part of the furnace body 110, and the first electrode 120 and the second electrode 130 are disposed perpendicular to each other. The first electrode 120 is a positive electrode, and the second electrode 130 is a negative electrode.

[0072] In some embodiments, the graphitization furnace 100 further includes a feeding unit, which includes a silo 151 and a material pipe 152. The silo 151 is disposed above the furnace body 110, and the silo 151 is connected to a material channel 111 in the furnace body 110 through the material pipe 152, and is used to feed the material to be graphitized into the material channel 111. Optionally, a material shut-off valve 153 may be further disposed at the connection between the silo 151 and the material pipe 152 to control the flow of the material in the material channel 111.

[0073] In some embodiments, the graphitization furnace 100 further includes a tail gas treatment unit 160, which is connected to the upper part of the material channel 111. The material entering the graphitization furnace 100 is a graphitizable carbonaceous material, such as petroleum coke, coal coke, and asphalt. After the material enters the material channel 111 of the graphitization furnace 100 from the feeding unit, it is graphitized in the material channel 111 to obtain a negative electrode graphite material product. The volatile tail gas emitted during the graphitization of the material is collected at the upper part of the material channel 111 and enters the tail gas treatment unit 160 for tail gas treatment.

[0074] In some embodiments, the graphitization furnace 100 further includes a cooling and discharging unit 170, which is disposed below the furnace body 110 and communicated with the bottom of the material channel 111, and is mainly used to cool the graphitized material and discharge the material. Figure 1 As shown, the cooling and discharging unit 170 is provided with a water cooling jacket, and the cooling medium may be circulating water. The graphitized material can be fully cooled down by the cooling and discharging unit 170, and the cooled material can be discharged through a discharging system (not shown), and the discharging system may be a material discharging screw.

[0075] In one embodiment of the present application, a battery production device (not shown) is provided, which includes the graphitization furnace 100 described above in the present application, and the graphitization furnace 100 is used to produce graphite materials for batteries. By adopting the graphitization furnace 100 described above in the present application, the battery production device of the present application has a longer service life.

[0076] It is understandable that the battery production equipment may include, in addition to the graphitization furnace 100 for producing the graphite material of the battery, related equipment for producing other battery materials.

[0077] The battery production equipment may be a battery production line, and a plurality of equipment in the battery production line may be arranged in the same centralized location, or may also be arranged in separate different locations.

[0078] It should be noted that in the above embodiments of the present application, only some structures in the graphitization furnace 100 are listed. In addition to the structures involved in the above embodiments, the graphitization furnace 100 in the present application may also include other system structures of the graphitization furnace in the relevant technology, such as the electrical system of the electrode, the clamping system of the electrode, etc. The relevant technical solutions of each system can refer to the specific description in the relevant technology, and will not be discussed in detail herein.

[0079] In order to make the technical problems, technical solutions and beneficial effects solved by the present application clearer, the present application will be further described in detail in conjunction with the embodiments below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present application and its applications. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0080] Embodiment 1:

[0081] (1) First electrode

[0082] A graphite electrode is used as the first electrode.

[0083] (2) Second electrode

[0084] A graphite electrode was used as the second substrate of the second electrode, and a thermally conductive adhesive containing 30% by mass of graphene, 30% by mass of graphite powder and 40% by mass of epoxy resin was coated on one end of the second substrate. The ratio of the coating length to the overall length of the second substrate was 1:3. After drying, a thermally conductive layer with a thickness of 20 μm was formed.

[0085] A waterproof layer slurry is coated on the thermal conductive layer, and the waterproof layer slurry includes 50% aluminum nitride by mass and 50% phenolic resin by mass, and after drying and curing, a waterproof layer with a thickness of 50μm is formed. Among them, the thermal conductivity of the thermal conductive layer is 50W / (m·k), and the number of grinding rotations of the thermal conductive layer is 6000; the number of grinding rotations of the waterproof layer is 10000, and the thermal conductivity of the waterproof layer is 20W / (m·k).

[0086] (3) Electrode assembly

[0087] The first electrode is used as the positive electrode of the graphitization furnace and installed in the material channel of the vertical graphitization furnace, and the first electrode is arranged along the extension direction of the material channel; the second electrode is used as the negative electrode and installed in the middle and lower part of the furnace body of the graphitization furnace, so that the part of the second substrate provided with the waterproof layer and the heat conductive layer is located outside the furnace body, and the second substrate extends into the material channel and is arranged at intervals from the first electrode; the negative electrode is arranged horizontally, the number of negative electrodes is 2, and multiple negative electrodes are arranged at intervals along the circumference of the material channel to assemble into a graphitization furnace.

[0088] (4) Service life and product performance evaluation

[0089] The graphite is produced by the above-mentioned graphitization furnace. Among the 300 tons of graphite produced, 2 tons of graphite have unqualified specific surface area indicators. After one month of continuous production, the mass loss of the second electrode is 1%. Among them, the mass loss of the second electrode = (the mass of the second electrode before production - the mass of the second electrode after production) / the mass of the second electrode before production × 100%.

[0090] Embodiment 2:

[0091] (1) First electrode

[0092] A graphite electrode is used as the first electrode.

[0093] (2) Second electrode

[0094] A graphite electrode was used as the second substrate of the second electrode, and a thermal conductive adhesive containing 20% ​​by mass of graphene, 30% by mass of graphite powder and 50% by mass of epoxy resin was coated on one end of the second substrate. The ratio of the coating length to the overall length of the second substrate was 1:3. After drying, a thermal conductive layer with a thickness of 20 μm was formed.

[0095] A waterproof layer slurry is coated on the thermal conductive layer, and the waterproof layer slurry includes 40% aluminum nitride by mass and 60% phenolic resin by mass. After drying and curing, a waterproof layer with a thickness of 50 μm is formed. Among them, the thermal conductivity of the thermal conductive layer is 45W / (m·k), and the number of grinding rotations of the thermal conductive layer is 7000; the number of grinding rotations of the waterproof layer is 9000, and the thermal conductivity of the waterproof layer is 15W / (m·k).

[0096] (3) Electrode assembly

[0097] The first electrode is used as the positive electrode of the graphitization furnace and installed in the material channel of the vertical graphitization furnace, and the first electrode is arranged along the extension direction of the material channel; the second electrode is used as the negative electrode and installed in the middle and lower part of the furnace body of the graphitization furnace, so that the part of the second substrate provided with the waterproof layer and the heat conductive layer is located outside the furnace body, and the second substrate extends into the material channel and is arranged at intervals from the first electrode; the negative electrode is arranged horizontally, the number of negative electrodes is 2, and multiple negative electrodes are arranged at intervals along the circumference of the material channel to assemble into a graphitization furnace.

[0098] (4) Service life and product performance evaluation

[0099] The graphite was produced by the graphitization furnace, and the specific surface area index of 4 tons of the graphite produced out of 300 tons was unqualified. After one month of continuous production, the mass loss of the second electrode was 2%.

[0100] Embodiment 3:

[0101] (1) First electrode

[0102] A graphite electrode is used as the first electrode.

[0103] (2) Second electrode

[0104] A graphite electrode was used as the second substrate of the second electrode, and a thermally conductive adhesive containing 15% by mass of graphene, 35% by mass of graphite powder and 50% by mass of epoxy resin was coated on one end of the second substrate. The ratio of the coating length to the overall length of the second substrate was 1:3. After drying, a thermally conductive layer with a thickness of 20 μm was formed.

[0105] A waterproof layer slurry is coated on the thermal conductive layer, and the waterproof layer slurry includes 30% by mass of aluminum nitride and 70% by mass of phenolic resin, and after drying and curing, a waterproof layer with a thickness of 50 μm is formed. Among them, the thermal conductivity of the thermal conductive layer is 40W / (m·k), and the number of grinding rotations of the thermal conductive layer is 8000; the number of grinding rotations of the waterproof layer is 8000, and the thermal conductivity of the waterproof layer is 10W / (m·k).

[0106] (3) Electrode assembly

[0107] The first electrode is used as the positive electrode of the graphitization furnace and installed in the material channel of the vertical graphitization furnace, and the first electrode is arranged along the extension direction of the material channel; the second electrode is used as the negative electrode and installed in the middle and lower part of the furnace body of the graphitization furnace, so that the part of the second substrate provided with the waterproof layer and the heat conductive layer is located outside the furnace body, and the second substrate extends into the material channel and is arranged at intervals from the first electrode; the negative electrode is arranged horizontally, the number of negative electrodes is 2, and multiple negative electrodes are arranged at intervals along the circumference of the material channel to assemble into a graphitization furnace.

[0108] (4) Service life and performance evaluation

[0109] The graphite was produced by the graphitization furnace. Among the 300 tons of graphite produced, 6 tons of graphite had unqualified specific surface area index. After one month of continuous production, the mass loss of the second electrode was 3%.

[0110] Comparative Example 1:

[0111] (1) Electrode assembly

[0112] A graphite electrode is used as a positive electrode of a graphitization furnace and installed in a material channel of a vertical graphitization furnace, and the first electrode is arranged along the extension direction of the material channel; a graphite electrode is used as a negative electrode and installed in the middle and lower part of a furnace body of the graphitization furnace, so that the part of the second substrate provided with a waterproof layer and a heat conductive layer is located outside the furnace body, and the second substrate extends into the material channel and is arranged at intervals from the first electrode; the negative electrode is arranged horizontally, the number of negative electrodes is 2, and a plurality of negative electrodes are arranged at intervals along the circumference of the material channel to assemble into a graphitization furnace.

[0113] (2) Service life and performance evaluation

[0114] The graphite furnace described above was used to produce graphite. Of the 300 tons of graphite produced, 25 tons had unqualified specific surface area indicators. After one month of continuous production, the mass loss of the second electrode was 10%.

[0115] Test method:

[0116] (1) Thermal conductivity test

[0117] Insert a hot wire into the graphite sample with coating, apply constant heating power to the hot wire to make its temperature rise, and then measure the relationship between the temperature rise of the hot wire itself or a certain distance parallel to the hot wire and time. Since the thermal conductivity of the material being tested determines this relationship, the thermal conductivity of the coating material can be obtained.

[0118] (2) Grinding times test

[0119] The JM-1 paint film abrasion tester was used to evaluate the wear resistance of the coating under the action of friction at 23±2℃ and relative humidity of 50±5%. Specifically: a circular graphite sample with a coating was provided, the sample was mounted on the abrasion tester, and a trimmed rubber grinding wheel was used for sanding; during the test, the wear of the coating surface was observed, and the sanding was stopped when the coating was obviously worn or worn through, and the number of grinding revolutions at this time was recorded.

[0120] (3) Thermal expansion coefficient test

[0121] Provide a graphite sample with coating as a composite sample, and provide a graphite sample without coating as a matrix sample; use precision measuring tools to measure the cross-sectional area A of the coating on the composite sample respectively. c and the cross-sectional area of ​​the matrix A s ; Under the same experimental environment, the thermal expansion coefficient α of the matrix sample was measured simultaneously using a thermal expansion instrument s and the thermal expansion coefficient α of the composite sample b According to the formula α c =(α b A b -α s A s ) / A c Calculate the thermal expansion coefficient of the coating, where A b is the total cross-sectional area of ​​the composite sample.

[0122] (4) Friction coefficient test

[0123] Take two 200mm×80mm coated graphite samples, fix one of them on the test plate of PCF-03 friction coefficient tester with double-sided tape, and fix the other sample on a special slider after cutting it to the appropriate size according to the test requirements; gently place the slider with the sample fixed on the center of the sample on the test plate, insert the vertical pin at the front of the slider into the sensor pin shaft hole, and ensure that the equipment sensor returns to the origin; press the test button to start the test, and the instrument automatically records the data and calculates the friction coefficient.

[0124] (5) Conductivity test

[0125] Provide a graphite sample with a coating, ensure that the coating surface is flat, clean, and free of oil, impurities, etc., to ensure good contact between the probe and the coating; gently place the four probes of the four-probe tester on the coating surface, so that the probes are in close contact with the coating and the spacing between the probes is kept equal; turn on the tester, set a suitable current value, pass current through the two outer probes through a constant current source, and measure the potential difference between the two middle probes at the same time; according to the measured current I, voltage U and probe spacing S, substitute into the formula ρ=2πSU / I to calculate the resistivity ρ; and then obtain the coating conductivity σ=1 / ρ.

[0126] The above description of various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced to each other, and for the sake of brevity, they will not be repeated herein.

[0127] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A graphitization furnace, characterized in that: include: A furnace body, wherein a material channel is arranged in the furnace body; a first electrode extending along a first direction and at least partially disposed in the material channel, wherein the first direction is an extending direction of the material channel; The second electrode has a polarity opposite to that of the first electrode; the second electrode includes a second substrate and a waterproof layer; one end of the second substrate is located in the material channel and is spaced apart from the first electrode, and the other end extends to the outside of the side wall of the furnace body; the waterproof layer is provided on the surface of the portion of the second substrate extending out of the furnace body.

2. The graphitization furnace according to claim 1, characterized in that: The material of the waterproof layer includes one or more of an inorganic hydrophobic material and an organic hydrophobic resin.

3. The graphitization furnace according to claim 2, characterized in that: Meet one or more of the following: (1) The inorganic hydrophobic material includes one or more of aluminum nitride, boron nitride, beryllium oxide, silicon nitride and silicon carbide; (2) The organic hydrophobic resin includes one or more of phenolic resin, epoxy resin, bismaleimide resin, vinyl resin and cyanate resin.

4. The graphitization furnace according to any one of claims 1 to 3, characterized in that: The thickness of the waterproof layer is 10 μm to 100 μm.

5. The graphitization furnace according to any one of claims 1 to 3, characterized in that: The waterproof layer is subjected to a grinding rotation frequency of 8000 to 10000 revolutions under the conditions of 23±2°C and a relative humidity of 50±5%.

6. The graphitization furnace according to any one of claims 1 to 3, characterized in that: The thermal conductivity of the waterproof layer is 0.5W / (m·k)~20W / (m·k).

7. The graphitization furnace according to any one of claims 1 to 3, characterized in that: The second electrode further comprises a heat-conducting layer, which is arranged on the surface of the portion of the second substrate extending out of the furnace body and is located between the second substrate and the waterproof layer.

8. The graphitization furnace according to claim 7, characterized in that: The material of the heat-conducting layer includes one or more of heat-conducting glue, heat-conducting silicone grease and heat-conducting ceramics.

9. The graphitization furnace according to claim 7, characterized in that: The thickness ratio of the heat conductive layer to the waterproof layer is 1:1-10.

10. The graphitization furnace according to claim 9, characterized in that: The thickness ratio of the heat conductive layer to the waterproof layer is 1:1-2.

5.

11. The graphitization furnace according to claim 7, characterized in that: The thickness of the heat conducting layer is 5 μm to 30 μm.

12. The graphitization furnace according to claim 7, characterized in that: The thermal conductivity ratio of the heat-conducting layer to the waterproof layer is 1-50:

1.

13. The graphitization furnace according to claim 12, characterized in that: The thermal conductivity ratio of the heat-conducting layer to the waterproof layer is 2-15:

1.

14. The graphitization furnace according to claim 7, characterized in that: The thermal conductivity of the thermal conductive layer is 2W / (m·k) to 50W / (m·k).

15. The graphitization furnace according to claim 7, characterized in that: The thermal conductive layer is rotated 6000 to 8000 times under the conditions of 23±2°C and 50±5% relative humidity.

16. The graphitization furnace according to any one of claims 1 to 3 and 8 to 15, characterized in that: The second substrate extends in a radial direction of the material channel.

17. The graphitization furnace according to any one of claims 1 to 3 and 8 to 15, characterized in that: There are multiple second electrodes, and the multiple second electrodes are arranged at intervals along the circumference of the material channel.

18. The graphitization furnace according to any one of claims 1 to 3 and 8 to 15, characterized in that: The first electrode is a positive electrode, and the second electrode is a negative electrode.

19. A battery production device, characterized in that: A graphitization furnace comprising any one of claims 1 to 18, wherein the graphitization furnace is used to produce graphite materials for batteries.

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