Graphite crucible for carbonizing lithium battery negative electrode material

Abstract

The application is suitable for the technical field of crucible furnace, and provides a graphite crucible for carbonizing lithium battery negative electrode material, which comprises two furnace bodies with furnace covers, a crucible and a heating mechanism arranged in the inner cavities of the furnace bodies, and the inner cavities of the two furnace bodies are communicated through two flow guide pipes, and an air extractor is installed on each flow guide pipe, a guide frame is arranged between the inner walls of the furnace bodies and the outer surface of the heating mechanism, two air ducts penetrating through the furnace bodies and communicated with the inner cavities of the furnace bodies are arranged on the furnace bodies, and the air duct at the bottom of one side of one furnace body is communicated with the air duct at the top of one side of the other furnace body through the flow guide pipe.The application realizes the circulation of hot air between the heated furnace body and the unheated furnace body by the flow guide pipe and the air extractor, effectively transfers the waste heat in the cavity of the heated furnace body to the unheated furnace body, preheats the negative electrode material in the unheated furnace body, significantly reduces the power consumption, improves the overall energy utilization rate, and realizes the recycling of the hot air between the two furnace bodies, reduces the heat loss, and greatly improves the utilization efficiency of unit energy.

Description

Technical Field

[0001] This invention relates to the field of crucible furnace technology, and more specifically, to a graphite crucible for carbonizing lithium battery anode materials. Background Technology

[0002] In lithium battery manufacturing, the performance of the anode material has a crucial impact on the overall battery performance. The carbonization process, as a key step in anode material production, directly affects the physicochemical properties of the anode material and the final battery performance. Traditional lithium battery anode material carbonization processes often employ a single furnace for heating. When using a single furnace, after the carbonized anode material is removed, the furnace needs to be cooled for a period, during which a large amount of heat is directly lost to the environment, resulting in significant energy waste. Furthermore, the long heating and cooling time required for a single furnace extends the overall production cycle and limits production efficiency. In addition, direct furnace heating, due to uneven arrangement of the resistance wires (leading to uneven temperature distribution within the furnace) and uneven packing of the anode material in the crucible, easily causes uneven heating of the anode material during carbonization, affecting material uniformity and product quality. Summary of the Invention

[0003] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a graphite crucible for carbonizing lithium battery anode materials.

[0004] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0005] This invention relates to a graphite crucible for carbonizing lithium battery anode materials, comprising two furnace bodies with furnace lids fixed on a support plate. A crucible and a heating mechanism are arranged in sequence from the inside to the outside of the furnace body. The two furnace bodies are connected by two guide pipes, each of which is equipped with an exhaust fan. A guide frame is provided between the inner walls of the furnace body and the outer surface of the heating mechanism, and the guide frame is sleeved on the heating mechanism.

[0006] Two air ducts that communicate with the inner cavity of the furnace body run through it. One air duct is located at the top of one side of the furnace body, and the other air duct is located at the bottom of one side of the furnace body. The air duct at the bottom of one side of the furnace body is connected to the air duct at the top of the other side of the furnace body through a guide pipe.

[0007] The guide frame includes two fixed rings, which are fixedly connected by several arc-shaped fixed plates arranged in a ring. A spiral guide plate is fixed between the two fixed rings. The inner arc surface of the guide spiral plate is in contact with the outer circular surface of the heating mechanism, and the outer arc surface of the guide spiral plate is in contact with the inner wall of the furnace.

[0008] As a preferred embodiment of the present invention, the top of the furnace body is fixed with an annular pressure plate and an annular sealing plate by bolts from bottom to top. The bottom of the annular pressure plate is fixed with a pressure ring that extends into the furnace cavity and contacts the fixing ring. The annular sealing plate has a through-hole in the middle that matches the furnace cover. The diameter of the through-hole is greater than or equal to the diameter of the crucible.

[0009] As a preferred embodiment of the present invention, the annular sealing plate includes an outer ring plate and an inner ring plate on the same axis. The inner ring plate passes through the outer ring plate. An opening for taking out and putting in the crucible is provided at the center of the inner ring plate. A clamping plate that cooperates with the inner ring plate is rotatably provided on the outer ring plate. The bottom of the inner ring plate passes through the outer ring plate and is pressed against the heating mechanism. A hinge seat that is hinged to the furnace cover is fixed on the outer ring surface of the outer ring plate.

[0010] As a preferred embodiment of the present invention, the furnace cover includes a cover body hinged to an outer ring plate. A sealing body is fixed to the bottom of the cover body by a support rod, which penetrates the inner ring plate and matches the opening for taking out and putting in the inner ring plate. A gas guide pipe communicating with the inner cavity of the crucible is passed through the center of the sealing body. The other end of the gas guide pipe passes through the cover body and extends to the outside of the cover body. An equidistant evacuation hole communicating with the inner cavity of the crucible is opened in an annular shape on the bottom edge of the sealing body. An annular gas collecting pipe communicating with the evacuation hole is fixed to the top of the sealing body. An evacuation pipe communicating with the inner cavity of the gas collecting pipe is fixed on the gas collecting pipe. The end of the evacuation pipe away from the gas collecting pipe passes through the cover body and extends to the outside of the cover body.

[0011] As a preferred embodiment of the present invention, the heating mechanism includes a cylindrical inner lining layer, and a plurality of annular grooves are equally spaced on the inner circular surface of the inner lining layer. A resistance wire is installed in the annular groove, and the resistance wire extends out of the annular groove or is flush with the inner circular surface of the inner lining layer.

[0012] As a preferred embodiment of the present invention, the gas guide pipes in the two furnace covers are connected by a flexible hose, and the two gas guide pipes are connected by a flexible hose.

[0013] As a preferred embodiment of the present invention, the guide spiral plate is provided with an installation groove that cooperates with the arc-shaped fixing plate, so that the outer arc surface of the arc-shaped fixing plate is flush with the outer circular surface of the fixing ring.

[0014] As a preferred embodiment of the present invention, both the cover and the furnace body are double-walled, with a hollow interlayer in the wall and refractory insulation cotton filling the hollow interlayer.

[0015] As a preferred embodiment of the present invention, the exhaust fan is mounted on a support plate via a fixed base.

[0016] The advantages of this invention are:

[0017] This invention utilizes a guide pipe and an exhaust fan to achieve hot air circulation between the heating furnace body and the unheated furnace body, effectively transferring the residual heat in the heating furnace body cavity to the unheated furnace body, preheating the negative electrode material in the unheated furnace body, significantly reducing power consumption, improving overall energy utilization, and the circulation of hot air between the two furnace bodies reduces heat loss, thus greatly improving the efficiency of unit energy utilization.

[0018] This invention, through the design of the guide frame, especially the spiral guide plate, creates an upward spiral cavity between the furnace body and the heating mechanism, promoting the uniform distribution of hot air within the furnace body and effectively improving the temperature uniformity within the furnace body. This results in more uniform heating of the negative electrode material during the carbonization process, thereby improving the uniformity and quality stability of the product.

[0019] The dual-furnace structure and hot air circulation mechanism of this invention shorten the overall heating and cooling time. While the heating furnace body carbonizes the negative electrode material, the unheated furnace body is preheated through hot air circulation, reducing the waiting time for heating. After heating is completed, the two furnace bodies can be rapidly cooled by adjusting the operation of the guide pipes and exhaust fans, further shortening the production cycle and improving overall production efficiency. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of a graphite crucible for carbonizing lithium battery anode materials according to the present invention.

[0021] Figure 2 This is a structural schematic diagram from another perspective of the present invention.

[0022] Figure 3 This is a cross-sectional structural diagram of the present invention.

[0023] Figure 4 This is a schematic diagram of the structure of a single furnace body and furnace cover in this invention.

[0024] Figure 5 For the present invention Figure 4 A schematic diagram of the cross-sectional structure.

[0025] Figure 6 This is a schematic diagram of the heating mechanism and guide frame of the present invention.

[0026] Figure 7 This is a schematic diagram of the guide frame of the present invention.

[0027] Figure 8 This is a front view of the guide frame of the present invention.

[0028] Figure 9 This is a schematic diagram of the heating mechanism of the present invention.

[0029] Figure 10This is a structural schematic diagram of the furnace cover from the bottom view of the present invention.

[0030] Figure 11 This is a cross-sectional structural diagram of the furnace cover of the present invention.

[0031] Figure 12 This is a schematic diagram of the structure of the annular pressure plate, the annular sealing plate and the furnace body of the present invention.

[0032] Figure 13 This is a schematic diagram of the structure of the annular sealing plate of the present invention.

[0033] Figure 14 This is a schematic cross-sectional view of the annular sealing plate of the present invention.

[0034] Figure 15 This is a schematic diagram of the cross-sectional structure of the furnace body of the present invention.

[0035] In the attached diagram: 1. Support plate;

[0036] 2. Furnace lid; 201. Lid body; 202. Support rod; 203. Sealing body; 204. Gas guide pipe; 205. Gas extraction hole; 206. Gas collecting pipe; 207. Gas extraction pipe;

[0037] 3. Furnace body; 4. Crucible;

[0038] 5. Heating mechanism; 501. Inner lining layer; 502. Annular groove; 503. Resistance wire;

[0039] 6. Drainage pipe; 7. Exhaust fan;

[0040] 8. Guide frame; 801. Fixing ring; 802. Arc-shaped fixing plate; 803. Guide spiral plate;

[0041] 9. Air duct; 10. Annular pressure plate;

[0042] 11. Annular sealing plate; 1101. Outer ring plate; 1102. Inner ring plate; 1103. Clamping plate;

[0043] 12. Hose. Detailed Implementation

[0044] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are for illustrative purposes only and are not intended to limit the scope of the invention. The invention is described more specifically in the following paragraphs by way of example with reference to the accompanying drawings. It should be noted that the drawings are in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0045] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is considered "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is considered "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0047] Example 1: Please refer to Figures 1-15 Structural diagram; the present invention provides the following technical solution:

[0048] Specifically, it refers to a graphite crucible for carbonizing lithium battery negative electrode materials, comprising two furnace bodies 3 with furnace lids 2 fixed on a support plate 1. The furnace bodies 3 have double walls with a hollow interlayer inside, filled with refractory insulation cotton. Inside the furnace body 3, a coaxial crucible 4 and a heating mechanism 5 are arranged sequentially from the inside out. The heating mechanism 5 includes a cylindrical inner lining 501, with several annular grooves 502 evenly spaced on the inner circular surface of the inner lining 501. Resistance wires 503 are installed within the annular grooves 502. Part 503 extends out of the annular groove 502 or is flush with the inner circular surface of the inner lining layer 501. The inner cavities of the two furnace bodies 3 are connected by two guide pipes 6. Each guide pipe 6 is equipped with an exhaust fan 7. The exhaust fan 7 is mounted on the support plate 1 through a fixed base. Two air guide pipes 9 pass through the furnace body 3 and are connected to the inner cavity of the furnace body 3. One air guide pipe 9 is located at the top of one side of the furnace body 3, and the other air guide pipe 9 is located at the bottom of one side of the furnace body 3. The air guide pipe 9 at the bottom of one side of the furnace body 3 is connected to the air guide pipe 9 at the top of one side of the other furnace body 3 through the guide pipe 6.

[0049] Through the guide pipe 6 with the exhaust fan 7, the heat in the heated furnace body 3 cavity can be transferred to the unheated furnace body 3 cavity, preheating the heating mechanism 5, crucible 4 and the negative electrode material in the crucible 4 in the furnace body 3 cavity, reducing power consumption and improving energy utilization.

[0050] A guide frame 8 is provided between the inner wall of the furnace body 3 and the outer surface of the heating mechanism 5. The guide frame 8 is sleeved on the heating mechanism 5. The guide frame 8 includes two fixing rings 801. The two fixing rings 801 are fixedly connected by several arc-shaped fixing plates 802 arranged in a ring. A spiral guide plate 803 is fixed between the two fixing rings 801. The inner arc surface of the guide spiral plate 803 is in contact with the outer circular surface of the heating mechanism 5, and the outer arc surface of the guide spiral plate 803 is in contact with the inner wall of the furnace body 3.

[0051] By placing a spiral guide plate 803 inside the furnace body 3 and fitting the guide plate 803 onto the heating mechanism 5, a connected but spirally upward cavity is formed between the furnace body 3 and the heating mechanism 5. After heating, the hot air inside the furnace body 3 is input from the air duct 9 on the top side of the furnace body 3 through the guide pipe 6 to the air duct 9 on the bottom side of the unheated furnace body 3. The air input from the bottom of the unheated furnace body 3 heats the internal structure of the furnace body 3 cavity (i.e., the hot furnace body 3 cavity where the heating mechanism 5 is installed heats the heating mechanism 5, crucible 4, and negative electrode material inside the unheated furnace body 3). At the same time, the cooler air inside the unheated furnace body 3 cavity is driven by the hot air and input through the top air duct 9 through the guide pipe 6 to the air duct 9 on the bottom side of the heated furnace body 3. After being heated inside the heated furnace body 3, it is input again through the above-mentioned flow process into the unheated furnace body 3 cavity.

[0052] The guide spiral plate 803 has an installation groove that matches the arc-shaped fixing plate 802, so that the outer arc surface of the arc-shaped fixing plate 802 is flush with the outer circular surface of the fixing ring 801, and the outer circular surface of the guide frame 8 is in close contact with the inner wall of the furnace body 3, which helps the air to flow along the guide spiral plate 803.

[0053] Example 2: Based on Example 1, the difference in this example is as follows:

[0054] like Figure 1 , Figure 5 , Figure 12 , Figure 13 , Figure 14 As shown, the top of the furnace body 3 is fixed with an annular pressure plate 10 and an annular sealing plate 11 by bolts from bottom to top. The bottom of the annular pressure plate 10 is fixed with a pressure ring that extends into the cavity of the furnace body 3 and contacts the fixing ring 801. The pressure ring is used to fix the guide frame 8 from the top. The annular sealing plate 11 has a through-hole in the middle that matches the furnace cover 2. The diameter of the through-hole is greater than or equal to the diameter of the crucible 4.

[0055] The annular sealing plate 11 includes an outer ring plate 1101 and an inner ring plate 1102, both coaxial. The inner ring plate 1102 penetrates the outer ring plate 1101. A loading / unloading port, which mates with the crucible 4, is located at the center of the inner ring plate 1102. The loading / unloading port is used to remove and place the crucible 4. A retaining plate 1103, which rotatably engages with the inner ring plate 1102, is mounted on the outer ring plate 1101. The retaining plate 1103 secures the outer ring plate 1101 and the inner ring plate 1102 together, facilitating maintenance and replacement of the heating mechanism 5 when needed. The bottom of the inner ring plate 1102 penetrates the outer ring plate 1101 and presses against the heating mechanism 5. A hinge seat, which is hinged to the furnace cover 2, is fixed on the outer ring surface of the outer ring plate 1101.

[0056] Example 3: Based on Example 2, the difference in this example is as follows:

[0057] like Figure 1 , Figure 5 , Figure 10 , Figure 11 As shown, the furnace cover 2 includes a cover body 201 hinged to the outer ring plate 1101. The cover body 201 is composed of a double-walled structure, with a hollow interlayer filled with refractory insulation cotton. A sealing body 203, which penetrates the inner ring plate 1102 and mates with the opening on the inner ring plate 1102, is fixed to the bottom of the cover body 201 by a support rod 202. A gas guide pipe 204, which communicates with the inner cavity of the crucible 4, passes through the center of the sealing body 203. The other end of the gas guide pipe 204 passes through the cover. The sealing body 203 has a body 201 that extends to the outside of the cover 201. The bottom edge of the sealing body 203 has annularly spaced air extraction holes 205 that communicate with the inner cavity of the crucible 4. The top of the sealing body 203 is fixed with an annular gas collecting pipe 206 that communicates with the air extraction holes 205. An air extraction pipe 207 that communicates with the inner cavity of the gas collecting pipe 206 is fixed on the gas collecting pipe 206. The end of the air extraction pipe 207 away from the gas collecting pipe 206 passes through the cover 201 and extends to the outside of the cover 201.

[0058] The gas guide pipes 204 in the two furnace covers 2 are connected by a flexible hose 12. The high-temperature hot exhaust gas generated during the heating process of the furnace body 3 is input to the unheated furnace body 3 through the flexible hose 12. The crucible 4 and the negative electrode material in the crucible 4 are preheated. After heat exchange with the crucible 4 and the negative electrode material in the crucible 4, the exhaust gas is discharged to the external exhaust gas purification system through the exhaust hole 205 and the gas collection pipe 206 in the top furnace cover 2 of the unheated furnace body 3 and finally through the exhaust pipe 207. This further improves the utilization of the heat generated during the heating process and reduces energy consumption.

[0059] The above are merely specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent substitutions, or modifications made based on the present invention to solve essentially the same technical problems and achieve essentially the same technical effects are all covered within the protection scope of the present invention.

Claims

1. A graphite crucible for carbonizing negative materials of lithium batteries, comprising two furnace bodies (3) with furnace covers (2) fixed on a support plate (1), and a crucible (4) and a heating mechanism (5) with coaxial lines arranged in the furnace body (3) from inside to outside, characterized in that: The inner wall of the furnace body (3) and the outer wall of the crucible (4) form an inner cavity of the furnace body (3); The inner cavities of the two furnace bodies (3) are communicated through the two flow guide pipes (6), and the flow guide pipes (6) are each provided with an air extractor (7); The inner wall of the furnace body (3) and the outer surface of the heating mechanism (5) are provided with a guide frame (8), and the guide frame (8) is sleeved on the heating mechanism (5); Two air guide pipes (9) are penetrated through the furnace body (3) and communicated with the inner cavity of the furnace body (3), one air guide pipe (9) is located at the top of one side of the furnace body (3), and the other air guide pipe (9) is located at the bottom of one side of the furnace body (3); The air guide pipe (9) at the bottom of one side of one furnace body (3) is communicated with the air guide pipe (9) at the top of one side of the other furnace body (3) through the flow guide pipe (6); The guide frame (8) comprises two fixed rings (801), the two fixed rings (801) are fixedly connected through a plurality of arc-shaped fixed plates (802) arranged in a ring shape, a guide spiral plate (803) in a spiral shape is fixed between the two fixed rings (801), the inner arc surface of the guide spiral plate (803) is attached to the outer circular surface of the heating mechanism (5), and the outer arc surface of the guide spiral plate (803) is attached to the inner wall of the furnace body (3); The heating mechanism (5) comprises a cylindrical inner lining layer (501), a plurality of annular grooves (502) are equidistantly formed on the inner circular surface of the inner lining layer (501), and a resistance wire (503) is mounted in each annular groove (502), and part of the resistance wire (503) protrudes out of the annular groove (502) or is flush with the inner circular surface of the inner lining layer (501).

2. The graphite crucible for carbonizing a lithium battery negative material according to claim 1, characterized in that, The top of the furnace body (3) is provided, from bottom to top, with a ring-shaped pressing plate (10) and a ring-shaped sealing plate (11) fixed by bolts, the bottom of the ring-shaped pressing plate (10) is provided with a pressing ring extending into the cavity of the furnace body (3) and in contact with the fixed ring (801), a through hole is formed in the middle of the ring-shaped sealing plate (11) and matched with the furnace cover (2), and the diameter of the through hole is greater than or equal to the diameter of the crucible (4).

3. The graphite crucible for carbonizing a lithium battery negative material according to claim 2, characterized by, The ring-shaped sealing plate (11) comprises coaxial outer and inner ring plates (1101) and (1102), the inner ring plate (1102) penetrates the outer ring plate (1101), a taking and placing hole is formed in the center of the inner ring plate (1102) and matched with the crucible (4), a clamping plate (1103) is rotatably arranged on the outer ring plate (1101) and matched with the inner ring plate (1102), the bottom of the inner ring plate (1102) penetrates the outer ring plate (1101) and is pressed on the heating mechanism (5), and a hinge seat is fixed on the outer ring surface of the outer ring plate (1101) and hinged with the furnace cover (2).

4. The graphite crucible for carbonizing a lithium battery negative material according to claim 1, characterized by, The furnace cover (2) comprises a cover body (201) hinged to an outer ring plate (1101), a sealing body (203) is fixed at the bottom of the cover body (201) by a support rod (202) and penetrates an inner ring plate (1102) and cooperates with a taking and placing opening on the inner ring plate (1102), a gas guide pipe (204) penetrates the center of the sealing body (203) and communicates with the inner cavity of the crucible (4), the other end of the gas guide pipe (204) penetrates the cover body (201) and extends to the outside of the cover body (201), the bottom edge of the sealing body (203) is annular and equidistantly provided with air extraction holes (205) which communicate with the inner cavity of the crucible (4), the top of the sealing body (203) is fixed with an annular gas collecting pipe (206) which communicates with the air extraction holes (205), the gas collecting pipe (206) is fixed with an air extraction pipe (207) which communicates with the inner cavity of the gas collecting pipe (206), and the end of the air extraction pipe (207) away from the gas collecting pipe (206) penetrates the cover body (201) and extends to the outside of the cover body (201).

5. The graphite crucible for carbonizing a lithium battery negative material according to claim 4, characterized by, The gas guide pipes (204) in the two furnace covers (2) are connected by a hose (12), and the two gas guide pipes (204) are communicated by the hose (12).

6. The graphite crucible for carbonizing a lithium battery negative material according to claim 1, characterized in that, An installation groove matched with the arc-shaped fixing plate (802) is formed in the guide spiral plate (803), so that the outer arc surface of the arc-shaped fixing plate (802) is flush with the outer cylindrical surface of the fixing ring (801).

7. The graphite crucible for carbonizing a lithium battery negative material according to claim 4, characterized by, The cover body (201) and the furnace body (3) are both double-walled, and a hollow interlayer is arranged in the wall body, and the hollow interlayer is filled with fire-resistant and heat-insulating cotton.

8. The graphite crucible for carbonizing a lithium battery negative material according to claim 1, characterized in that, The air extraction fan (7) is installed on the support plate (1) by a fixing base.

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