Tunnel kiln and battery production line

Abstract

The utility model provides a tunnel kiln and a battery production line. The kiln body comprises a kiln wall; the gas conveying channel is suitable for conveying the protective atmosphere and comprises a first heat exchange section and a second heat exchange section which are connected with each other, the first heat exchange section is located in the kiln wall and suitable for enabling the protective atmosphere in the first heat exchange section to exchange heat with the kiln wall, and at least part of the second heat exchange section protrudes out of the kiln wall and is located in the kiln body; and the protective atmosphere in the second heat exchange section exchanges heat with gas in the kiln body, and a gas outlet is formed in the end of the second heat exchange section. In the structure, the protective atmosphere can be subjected to two-section heat exchange in the gas transmission channel, so that the protective atmosphere is fully preheated, and the error requirement of the sintering temperature is met.

Description

Technical Field

[0001] The utility model relates to the technical field of battery production equipment, in particular to a tunnel kiln and a battery production line. Background Art

[0002] During the production of lithium batteries, the battery raw materials need to be transferred to the roller kiln. The roller kiln relies on electric energy to heat the protective atmosphere inside the kiln body, thereby achieving the effect of high-temperature sintering of the electrode materials. The stability of the protective atmosphere inside the kiln body and the temperature uniformity of the material will directly affect the final sintering quality. Furthermore, in order to ensure that the atmosphere inside the kiln body is evenly distributed near the raw materials, air outlets are usually provided at the bottom and sides of the roller kiln to supplement the protective atmosphere. If the temperature of the supplemented protective atmosphere is low, it will affect the sintering temperature, which may easily cause problems such as poor sintering quality. Therefore, it is necessary to preheat the protective atmosphere in advance in the prior art, and the temperature of the protective atmosphere before introduction is quite different from the temperature in the kiln (the protective atmosphere before introduction is room temperature, and the reaction temperature in the kiln is about 1000°C). The roller kiln in the prior art does not preheat the protective atmosphere sufficiently, and it is difficult to meet the temperature error requirements of sintering, which affects the sintering quality of the battery electrode materials. Utility Model Content

[0003] Therefore, the technical problem to be solved by the utility model is to overcome the defect of the roller kiln in the prior art that the protective atmosphere introduced is not sufficiently preheated, thereby providing a tunnel kiln and a battery production line.

[0004] In order to solve the above problems, the utility model provides a tunnel kiln, comprising: a kiln body, including a kiln wall; a gas delivery channel, suitable for delivering a protective atmosphere, the gas delivery channel comprising a first heat exchange section and a second heat exchange section connected to each other, the first heat exchange section is located in the kiln wall, and is suitable for the protective atmosphere in the first heat exchange section to exchange heat with the kiln wall, at least part of the second heat exchange section protrudes from the kiln wall and is located in the kiln body, and is suitable for the protective atmosphere in the second heat exchange section to exchange heat with the gas in the kiln body, and the end of the second heat exchange section forms an air outlet.

[0005] Optionally, the first heat exchange section has at least one bending section.

[0006] Optionally, the kiln wall is formed by stacking kiln bricks, a flow channel is opened in the kiln bricks, the flow channel forms the first heat exchange section and / or the first heat exchange section is a pipeline structure arranged in the kiln bricks.

[0007] Optionally, the flow channel in the second heat exchange section is bent.

[0008] Optionally, the second heat exchange section includes: a first tube body, having an air inlet side and an air outlet side; a second tube body, arranged in the first tube body, the end of the second tube body facing the air inlet side is a closed end, and an end of the side wall of the second tube body facing the air outlet side is provided with an air outlet; a third tube body, arranged in the second tube body, the end of the third tube body facing the air outlet side forms an air outlet; an annular closing plate, covered on the air outlet side of the first tube body, and the ends of the first tube body, the second tube body and the third tube body are connected to the annular closing plate.

[0009] Optionally, the side wall of the first tube body, and / or the side wall of the second tube body, and / or the side wall of the third tube body are corrugated.

[0010] Optionally, the end of the first heat exchange section forms an installation opening on the side wall of the kiln wall, part of the second heat exchange section is inserted into the installation opening, a heat conductive layer is provided on the outer wall of the second heat exchange section, and the heat conductive layer is sandwiched between the outer wall of the second heat exchange section and the inner wall of the installation opening.

[0011] Optionally, the kiln wall comprises a bottom wall and a side wall, and a second heat exchange section is arranged on the bottom wall and / or the side wall.

[0012] Optionally, the kiln wall includes a first side wall and a second side wall opposite to each other, and the first side wall and the second side wall are both provided with a second heat exchange section, and along the flow direction of the material, the second heat exchange section on the first side wall and the second heat exchange section on the second side wall are staggered.

[0013] The utility model also provides a battery production line, comprising the above-mentioned tunnel kiln.

[0014] The utility model has the following advantages:

[0015] By utilizing the technical solution of the utility model, when the tunnel kiln is working, the protective atmosphere is introduced into the kiln body through the gas transmission channel. The protective atmosphere first passes through the first heat exchange section, where the protective atmosphere exchanges heat with the high-temperature kiln wall. Then the protective atmosphere passes through the second heat exchange section, where the protective atmosphere exchanges heat with the high-temperature gas in the kiln body, and is finally discharged from the gas outlet. In the above structure, the protective atmosphere can undergo two-stage heat exchange in the gas transmission channel, thereby fully preheating the protective atmosphere to meet the error requirements of the sintering temperature. Therefore, the technical solution of the utility model solves the defect of the roller kiln in the prior art that the introduced protective atmosphere is not sufficiently preheated. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 The schematic diagram of the structure of the tunnel kiln of the utility model is shown;

[0018] Figure 2 Shows Figure 1 Side view of the middle tunnel kiln (partially in cross-section);

[0019] Figure 3 Shows Figure 1 Main cross-sectional view of the middle tunnel kiln;

[0020] Figure 4 Shows Figure 3 The enlarged schematic diagram at A in the middle;

[0021] Figure 5 Shows Figure 1 Schematic diagram of the structure of the gas transmission channel of the middle tunnel kiln;

[0022] Figure 6 Shows Figure 5 A cross-sectional view of the second heat exchange section of the middle gas transmission channel;

[0023] Figure 7 Shows Figure 6 A schematic structural diagram of a second tube body in a second heat exchange section;

[0024] Figure 8 Shows Figure 1 Top view of the tunnel kiln.

[0025] Description of reference numerals:

[0026] 10. kiln body; 11. bottom wall; 12. side wall; 121. first side wall; 122. second side wall; 20. gas transmission channel; 21. first heat exchange section; 22. second heat exchange section; 221. first tube body; 2211. air inlet side; 2212. air outlet side; 222. second tube body; 2221. air outlet; 223. third tube body; 224. annular closing plate; 23. air outlet; 30. installation port; 40. heat conduction layer. DETAILED DESCRIPTION

[0027] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0031] like Figures 1 to 5 As shown, an embodiment of a tunnel kiln according to the present application includes a kiln body 10 and a gas delivery channel 20. The kiln body 10 includes a kiln wall. The gas delivery channel 20 is suitable for delivering a protective atmosphere, and the gas delivery channel 20 includes a first heat exchange section 21 and a second heat exchange section 22 connected to each other. The first heat exchange section 21 is located in the kiln wall, and is suitable for the protective atmosphere in the first heat exchange section 21 to exchange heat with the kiln wall. At least part of the second heat exchange section 22 protrudes from the kiln wall and is located in the kiln body 10, and is suitable for the protective atmosphere in the second heat exchange section 22 to exchange heat with the gas in the kiln body 10. The end of the second heat exchange section 22 forms a gas outlet 23.

[0032] By using the technical solution of this embodiment, when the tunnel kiln is working, the protective atmosphere is introduced into the kiln body 10 through the gas supply channel 20. The protective atmosphere first passes through the first heat exchange section 21, where the protective atmosphere exchanges heat with the high-temperature kiln wall. Then the protective atmosphere passes through the second heat exchange section 22, where the protective atmosphere exchanges heat with the high-temperature gas in the kiln body 10, and is finally discharged from the gas outlet 23. In the above structure, the protective atmosphere can undergo two-stage heat exchange in the gas supply channel 20, thereby fully preheating the protective atmosphere to meet the error requirements of the sintering temperature. Therefore, the technical solution of this embodiment solves the defect of the roller kiln in the prior art that the introduced protective atmosphere is not sufficiently preheated.

[0033] from Figure 1 It can be seen that the kiln wall of the kiln body 10 includes a top wall, a side wall 12 and a bottom wall 11, and the front and rear ends of the kiln body 10 are respectively provided with an inlet and an outlet, so that the kiln body 10 forms a tunnel-like structure. The material to be sintered can enter from the inlet of the kiln body 10, and can be taken out from the outlet of the kiln body 10 after sintering.

[0034] It should be noted that the tunnel kiln in this embodiment is used to sinter electrode materials for lithium batteries, and the tunnel kiln is a roller kiln. A plurality of conveying rollers are provided in the kiln body 10. The containing box containing the electrode material flows in the kiln body 10 through the conveying rollers, and the sintering reaction is carried out in a high-temperature protective atmosphere.

[0035] Of course, the above-mentioned tunnel kiln can also be used to sinter other materials, not limited to electrode materials for lithium batteries.

[0036] like Figures 2 to 5 As shown, the tunnel kiln also includes a gas delivery channel 20, the function of which is to pass the protective atmosphere into the kiln body 10, so that the material can be sintered at high temperature under the protective atmosphere. The gas delivery channel 20 includes two interconnected pipe sections, namely, a first heat exchange section 21 and a second heat exchange section 22. The end of the first heat exchange section 21 forms an air inlet, which can be connected to an external device or pipeline, and the protective atmosphere can enter the gas delivery channel 20 from the air inlet. After the protective atmosphere exchanges heat in the first heat exchange section 21 and the second heat exchange section 22 and increases the temperature, the protective atmosphere is discharged into the kiln body 10 from the air outlet 23 at the end of the second heat exchange section 22.

[0037] like Figure 2 , Figure 3 and Figure 5 As shown, in this embodiment, the first heat exchange section 21 is located in the kiln wall, where "located in the kiln wall" means that the first heat exchange section 21 is embedded in the kiln wall. Since the kiln wall absorbs heat and is at a relatively high temperature when the tunnel kiln is working, the protective atmosphere can exchange heat with the kiln wall when flowing in the first heat exchange section 21, that is, absorb the heat of the kiln wall and increase the temperature.

[0038] Furthermore, the above-mentioned “kiln wall” may refer to one, two or three of the bottom wall 11 , the side wall 12 and the top wall of the tunnel kiln.

[0039] For example, the first heat exchange section 21 may flow through the bottom wall 11 of the tunnel kiln, or the first heat exchange section 21 may flow through the side wall 12 of the tunnel kiln;

[0040] For another example, the first heat exchange section 21 may flow through the bottom wall 11 and the side wall 12 of the tunnel kiln, or the first heat exchange section 21 may flow through the side wall 12 and the top wall of the tunnel kiln;

[0041] For another example, the first heat exchange section 21 may flow through the bottom wall 11 , the side wall 12 , and the top wall of the tunnel kiln.

[0042] Those skilled in the art can understand that the longer the length of the first heat exchange section 21 is, the longer the protective atmosphere flows, the larger the heat exchange area is, the longer the heat exchange time is, and the better the preheating effect is. Those skilled in the art can adjust the length of the first heat exchange section 21 and its position on the kiln body 10 according to actual needs.

[0043] like Figure 4 As shown, the second heat exchange section 22 is connected to the inner wall of the kiln wall, and at least part of the second heat exchange section 22 protrudes from the kiln wall and is located in the kiln body 10. Specifically, "at least part of the second heat exchange section 22 protrudes from the kiln wall and is located in the kiln body 10" means that the second heat exchange section 22 can be directly connected to the end surface of the kiln wall at one end, so that the second heat exchange section 22 is completely located in the kiln body 10, or the second heat exchange section 22 can be partially inserted into the kiln wall (for example Figure 4 As shown), the remaining portion of the second heat exchange section 22 is located within the kiln body 10.

[0044] When the tunnel kiln is working, the interior of the kiln body 10 is a high-temperature environment (the reaction temperature required is about 1000°C). Therefore, after the protective atmosphere flows from the first heat exchange section 21 into the second heat exchange section 22, it can exchange heat with the high-temperature gas in the kiln body 10 in the second heat exchange section 22, absorb heat, and thus further increase the temperature of the protective atmosphere.

[0045] It can be seen that in the tunnel kiln of this embodiment, the protective atmosphere can be heated in two stages after passing through the first heat exchange section 21 and the second heat exchange section 22, so that the protective atmosphere can be fully preheated before entering the kiln body 10. The temperature of the protective atmosphere can be more easily reached to the required temperature through the two-stage heating, thereby ensuring the quality of the subsequent sintering of the electrode material.

[0046] like Figure 5As shown, in the technical solution of this embodiment, the first heat exchange section 21 has at least one bending section. Specifically, the length of the first heat exchange section 21 can be lengthened by the bending section, so that the first heat exchange section 21 can extend the flow distance of the protective atmosphere while occupying the smallest possible area, thereby improving the heating effect of the protective atmosphere.

[0047] In this embodiment, the first heat exchange section 21 has a plurality of bending sections. Figure 5 The extension method of the first heat exchange section 21 in this embodiment is described in detail:

[0048] Path 1: The first heat exchange section 21 initially extends in the horizontal direction; Path 2: Then it extends in the opposite direction in the horizontal direction through a bend section; Path 3: Then it extends horizontally for a short distance toward the inside of the kiln body 10 through a bend section; Path 4: Then it extends downward through a bend section; Path 5: Then it extends in a spiral shape (a clockwise spiral in this embodiment) through multiple bend sections.

[0049] Furthermore, the second heat exchange section 22 is connected to the end of the spiral structure.

[0050] Such arrangement of the first heat exchange section 21 can greatly extend the flow distance of the protective atmosphere, thereby improving the heating effect.

[0051] Of course, those skilled in the art can design the specific extension path of the first heat exchange section 21 according to actual needs, and are not limited to Figure 5 The method shown.

[0052] like Figure 2 and Figure 3 As shown, in the technical solution of this embodiment, the kiln wall is formed by stacking kiln bricks, and a flow channel is opened in the kiln bricks, and the flow channel forms the first heat exchange section 21.

[0053] Specifically, grooves are made on the kiln bricks to form flow channels, and when the kiln bricks are stacked to form the kiln wall, the flow channels on the multiple kiln bricks together surround the first heat exchange section 21. Those skilled in the art can determine the position and direction of the flow channels required to be opened on each kiln brick based on the design model of the first heat exchange section 21 and conventional design software, so that the first heat exchange section 21 is formed after the kiln bricks are stacked to form the kiln wall.

[0054] The first heat exchange section 21 is formed in this way, so that the protective atmosphere directly exchanges heat with the kiln bricks without the need for a pipeline structure to conduct heat, thereby improving the heat exchange efficiency and enhancing the heating effect on the protective atmosphere.

[0055] Optionally, the flow channel surface of the kiln bricks needs to be coated with a layer of high temperature resistant mortar to prevent dust on the kiln bricks from entering the kiln body 10 along the first heat exchange section 21 and the second heat exchange section 22 .

[0056] Alternatively, if Figure 1 As shown, since the temperature of the kiln bricks near the inside of the kiln body 10 is relatively high, the first heat exchange section 21 should be opened as close to the inside of the kiln body 10 as possible while ensuring the strength of the kiln bricks, so as to improve its heat exchange efficiency. Therefore, the path 3 of the first heat exchange section 21 above makes the spiral structure of the path 4 as close to the inside of the kiln body 10 as possible, so as to improve the heat exchange efficiency of the protective atmosphere.

[0057] Of course, in some embodiments not shown, the first heat exchange section 21 may also be a pipeline structure, and the first heat exchange section 21 is embedded in the kiln wall by pre-embedded means, so as to achieve heat exchange between the first heat exchange section 21 and the kiln bricks. In this embodiment, the first heat exchange section 21 is more convenient to set up, but the heat exchange needs to be transferred through the pipe wall of the pipeline structure, and the heat exchange efficiency is slightly reduced compared with the above-mentioned method of forming the first heat exchange section 21 through the flow channel.

[0058] like Figure 6 As shown, in the technical solution of this embodiment, the flow channel in the second heat exchange section 22 is bent. This arrangement allows the protective atmosphere to flow in the second heat exchange section 22 in a reciprocating flow path, thereby increasing the flow distance of the protective atmosphere in the second heat exchange section 22 and further improving the heat exchange effect.

[0059] like Figure 6 As shown, the second heat exchange section 22 includes a first tube body 221, a second tube body 222, a third tube body 223 and an annular sealing plate 224. The following describes each structure in detail:

[0060] like Figure 6 As shown, the first tube body 221 is a tubular structure, both ends of which are open ends. The first tube body 221 has an air inlet side 2211 and an air outlet side 2212. The air inlet side 2211 refers to the side where the protective atmosphere enters the first tube body 221, that is, the air inlet side 2211 of the first tube body 221 is connected to the first heat exchange section 21. The air outlet side 2212 refers to the side where the protective atmosphere is discharged from the first tube body 221, that is, the protective atmosphere is discharged from the air outlet side 2212 of the first tube body 221 into the kiln body 10.

[0061] like Figure 6 As shown, the diameter of the second tube body 222 is slightly smaller than the diameter of the first tube body 221, the length of the second tube body 222 is smaller than the length of the first tube body 221, and the second tube body 222 is arranged inside the first tube body 221, and the first tube body 221 and the second tube body 222 are arranged coaxially. The end of the second tube body 222 facing the air inlet side 2211 is a closed end, and the end of the second tube body 222 facing the air outlet side 2212 is an open end. Further, an air outlet 2221 is provided at one end of the side wall of the second tube body 222 facing the air outlet side 2212. A first flow channel is formed between the first tube body 221 and the second tube body 222.

[0062] like Figure 6 As shown, the diameter of the third tube body 223 is slightly smaller than the diameter of the second tube body 222, the length of the third tube body 223 is smaller than the length of the second tube body 222, and the third tube body 223 is arranged inside the second tube body 222, and the third tube body 223 and the second tube body 222 are coaxially arranged. Both ends of the third tube body 223 are open ends, and the end of the third tube body 223 facing the gas outlet side 2212 forms an outlet 23. A second flow channel is formed between the second tube body 222 and the third tube body 223, and a third flow channel is formed inside the third tube body 223.

[0063] like Figure 6 As shown, in the direction toward the gas outlet side 2212, the ends of the first tube body 221, the second tube body 222 and the third tube body 223 are aligned. The annular closing plate 224 is a circular ring structure, whose outer diameter is adapted to the diameter of the first tube body 221, and whose inner diameter is adapted to the diameter of the third tube body 223. The annular closing plate 224 is covered on the gas outlet side 2212 of the first tube body 221, and the ends of the first tube body 221, the second tube body 222 and the third tube body 223 are connected to the annular closing plate 224.

[0064] The annular closing plate 224 serves to fix the relative positions of the first tube body 221 , the second tube body 222 and the third tube body 223 . Meanwhile, the annular closing plate 224 also makes the flow directions of the first flow channel and the second flow channel opposite.

[0065] like Figure 6 As shown, through the above structure, after the protective atmosphere enters the first tube body 221, it first flows toward the gas outlet side 2212 through the first flow channel; then the protective atmosphere flows to the second flow channel through the gas port 2221, and flows toward the gas inlet side 2211; then the protective atmosphere turns back in the closed section of the second tube body 222 and flows to the third flow channel, flows toward the gas outlet side 2212, and finally flows out from the gas outlet 23. Therefore, the above structure makes the flow channel in the second heat exchange section 22 bend twice as a whole, which increases the flow distance of the protective atmosphere in the second heat exchange section 22, increases the heat exchange area, improves the heat exchange efficiency, and has a better preheating effect on the protective atmosphere.

[0066] At the same time, for the second flow channel, the protective atmosphere temperature in the first flow channel outside it is lower, and the protective atmosphere temperature in the third flow channel inside it is higher, that is, the heat exchange surface has both cold and hot surfaces, so the heat exchange temperature of the protective atmosphere is uniform.

[0067] like Figure 6 and Figure 7As shown, in the technical solution of this embodiment, the side wall of the second tube body 222 is a corrugated structure, that is, the cross section of the side wall is a continuous "S"-shaped structure. The corrugated structure can increase the heat exchange area of ​​the protective atmosphere, thereby further improving the heat exchange effect.

[0068] In some embodiments not shown, the side wall of the first tube body 221 or the third tube body 223 may also be a corrugated structure.

[0069] Furthermore, the side wall of one, two, or all of the first tube body 221, the second tube body 222, and the third tube body 223 may be in a corrugated structure.

[0070] like Figure 4 As shown, in the technical solution of this embodiment, the end of the first heat exchange section 21 forms a mounting opening 30 on the side wall of the kiln wall. Part of the second heat exchange section 22 is inserted into the mounting opening 30, and a heat conductive layer 40 is provided on the outer side wall of the second heat exchange section 22, and the heat conductive layer 40 is sandwiched between the outer side wall of the second heat exchange section 22 and the inner side wall of the mounting opening 30.

[0071] Specifically, the installation opening 30 is the end position of the first heat exchange section 21, and the installation opening 30 is a round hole structure. Part of the first tube body 221 of the second heat exchange section 22 can be inserted into the installation opening 30, thereby realizing the docking between the first heat exchange section 21 and the second heat exchange section 22, that is, the outlet of the first heat exchange section 21 is connected to the inlet of the second heat exchange section 22. At the same time, the above structure also makes the installation process of the second heat exchange section 22 simple.

[0072] The heat-conducting layer 40 is a soft heat-conducting silicone pad. The silicone pad is in a cylindrical structure, and is sleeved outside the air inlet side 2211 of the first tube body 221 , and the silicone pad is in close contact with the inner wall of the installation opening 30 .

[0073] On one hand, the heat-conducting layer 40 can fix the first tube body 221 so that the first tube body 221 is tightly inserted in the installation opening 30; on the other hand, the heat-conducting layer 40 can enhance the heat conduction effect between the kiln bricks and the first tube body 221, and has a better preheating effect on the protective atmosphere.

[0074] like Figure 1 As shown, in the technical solution of this embodiment, the kiln wall includes a bottom wall 11 and a side wall 12 , and a second heat exchange section 22 is provided on the bottom wall 11 and / or the side wall 12 .

[0075] Specifically, those skilled in the art may choose to supplement the protective atmosphere at the bottom or side of the kiln body 10 according to actual needs.

[0076] In the embodiment, the second heat exchange section 22 is provided on the side wall 12 of the kiln body 10 , so as to supplement the protective atmosphere to the side of the kiln body 10 .

[0077] In an embodiment not shown, the second heat exchange section 22 mentioned above may also be provided on the bottom wall 11 of the kiln body 10 , so as to supplement the protective atmosphere at the bottom of the kiln body 10 .

[0078] In an embodiment not shown, the second heat exchange section 22 may be provided on both the bottom wall 11 and the side wall 12 of the kiln body 10 , so as to supplement the protective atmosphere at the bottom and the side of the kiln body 10 .

[0079] like Figure 8 As shown, in the technical solution of this embodiment, the kiln wall includes a first side wall 121 and a second side wall 122 opposite to each other, and the first side wall 121 and the second side wall 122 are both provided with a second heat exchange section 22. In the flow direction of the material, the second heat exchange section 22 on the first side wall 121 and the second heat exchange section 22 on the second side wall 122 are staggered.

[0080] Such an arrangement can avoid the situation where the protective atmosphere in the middle is disturbed due to the opposite blowing of airflows on both sides, thereby reducing the protective atmosphere content in the middle.

[0081] Furthermore, a plurality of second heat exchange sections 22 may be disposed on each of the first side wall 121 and the second side wall 122. Figure 5 As shown, for one of the first side wall 121 and the second side wall 122, the first heat exchange section 21 may include a main pipe and branch pipes (path 1 and path 2 of the above-mentioned first heat exchange section 21 form the main pipe, and path 3, path 4 and path 5 of the above-mentioned first heat exchange section 21 form branch pipes), there are several branch pipes and they are all connected to the main pipe, and the end of each branch pipe is connected to a second heat exchange section 22.

[0082] Optionally, in this embodiment, two second heat exchange sections 22 are disposed on the first side wall 121 and the second side wall 122 . Of course, a greater number of second heat exchange sections 22 may also be disposed on the first side wall 121 and the second side wall 122 .

[0083] The present application also provides a battery production line, comprising the above-mentioned tunnel kiln.

[0084] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A tunnel kiln, characterized in that: include; A kiln body (10), including a kiln wall; The gas delivery channel (20) is suitable for delivering a protective atmosphere. The gas delivery channel (20) comprises a first heat exchange section (21) and a second heat exchange section (22) which are connected to each other. The first heat exchange section (21) is located in the kiln wall and is suitable for the protective atmosphere in the first heat exchange section (21) to exchange heat with the kiln wall. At least a portion of the second heat exchange section (22) protrudes from the kiln wall and is located in the kiln body (10), and is suitable for the protective atmosphere in the second heat exchange section (22) to exchange heat with the gas in the kiln body (10). The end of the second heat exchange section (22) forms a gas outlet (23).

2. The tunnel kiln according to claim 1, characterized in that: The first heat exchange section (21) has at least one bending section.

3. The tunnel kiln according to claim 1, characterized in that: The kiln wall is formed by stacking kiln bricks, a flow channel is opened in the kiln bricks, and the flow channel forms the first heat exchange section (21); and / or the first heat exchange section (21) is a pipeline structure arranged in the kiln bricks.

4. The tunnel kiln according to claim 1, characterized in that: The flow channel in the second heat exchange section (22) is in a bent shape.

5. The tunnel kiln according to claim 4, characterized in that: The second heat exchange section (22) comprises: The first tube body (221) has an air inlet side (2211) and an air outlet side (2212); A second tube body (222) is arranged inside the first tube body (221), the end of the second tube body (222) facing the air inlet side (2211) is a closed end, and an air outlet (2221) is provided at one end of the side wall of the second tube body (222) facing the air outlet side (2212); A third tube body (223) is arranged inside the second tube body (222), and the end of the third tube body (223) facing the gas outlet side (2212) forms the gas outlet (23); An annular closing plate (224) is provided to cover the gas outlet side (2212) of the first tube body (221), and ends of the first tube body (221), the second tube body (222) and the third tube body (223) are connected to the annular closing plate (224).

6. The tunnel kiln according to claim 5, characterized in that: The side wall of the first tube body (221), and / or the side wall of the second tube body (222), and / or the side wall of the third tube body (223) are corrugated.

7. The tunnel kiln according to claim 1, characterized in that: The end of the first heat exchange section (21) forms a mounting opening (30) on the side wall of the kiln wall, a portion of the second heat exchange section (22) is inserted into the mounting opening (30), a heat conducting layer (40) is provided on the outer side wall of the second heat exchange section (22), and the heat conducting layer (40) is sandwiched between the outer side wall of the second heat exchange section (22) and the inner side wall of the mounting opening (30).

8. The tunnel kiln according to any one of claims 1 to 7, characterized in that: The kiln wall comprises a bottom wall (11) and a side wall (12), and the second heat exchange section (22) is arranged on the bottom wall (11) and / or the side wall (12).

9. The tunnel kiln according to any one of claims 1 to 7, characterized in that: The kiln wall comprises a first side wall (121) and a second side wall (122) opposite to each other, and the first side wall (121) and the second side wall (122) are both provided with the second heat exchange section (22), and along the flow direction of the material, the second heat exchange section (22) on the first side wall (121) and the second heat exchange section (22) on the second side wall (122) are staggered.

10. A battery production line, characterized in that: Comprising the tunnel kiln as claimed in any one of claims 1 to 9.

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