Battery electrode coating and drying system

Abstract

The application relates to a battery electrode coating and drying system, and belongs to the technical field of battery production. The battery electrode coating and drying system comprises an oven, an air inlet pipeline, an air outlet pipeline, a heat exchanger and a chemical heat pump structure. The air inlet pipeline is connected to a first gas passage, the air outlet pipeline is connected to a second gas passage, heat exchange is carried out between the first gas passage and the second gas passage, the chemical heat pump structure converts low-grade heat of gas in the air outlet pipeline into high-grade heat through a chemical reaction, and the high-grade heat is used to heat gas in the air inlet pipeline. The battery electrode coating and drying system provided by the application realizes recycling of heat of high-temperature waste gas, the recycling rate of recycled energy by the chemical reaction is high, the utilization rate of energy is improved, and energy waste is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery production, in particular to a battery electrode coating and drying system. BACKGROUND

[0002] Coating is to uniformly coat the positive and negative electrode material slurry on the electrode foil, and to dry the organic solvent in the slurry. It is also one of the key links of battery production and manufacturing with the highest energy consumption. The existing coating and drying system mainly uses hot air circulation. In the initial stage of drying, hot air rapidly sweeps over the surface of the coating slurry, heats the slurry, and promotes the evaporation of the slurry surface solvent and the diffusion of the gas-liquid two-phase through the interface. The process of drying the pole piece consumes a large amount of energy, and a large amount of air is heated to about 110-140℃. Therefore, the coating and drying system will discharge high-temperature waste gas, causing energy waste. SUMMARY

[0003] Therefore, it is necessary to provide a battery electrode coating and drying system to solve the technical problem that the existing coating and drying system is easy to cause energy waste.

[0004] To achieve the above-mentioned purpose, the present application provides a battery electrode coating and drying system, which comprises:

[0005] An oven transmits a pole piece inside;

[0006] An air inlet pipeline is communicated with the oven at one end, and the air inlet pipeline is used to deliver hot air to the pole piece;

[0007] An air outlet pipeline is communicated with the oven at one end, and the air outlet pipeline is used to discharge high-temperature waste gas in the oven;

[0008] A heat exchanger has a first gas passage and a second gas passage capable of heat exchange, the air inlet pipeline is communicated with the first gas passage, and the air outlet pipeline is communicated with the second gas passage; and

[0009] A chemical heat pump structure has an endothermic end and an exothermic end, the endothermic end is arranged on the air outlet pipeline away from the oven of the heat exchanger, the exothermic end is arranged on the air inlet pipeline between the heat exchanger and the oven, the heat of the air outlet pipeline can cause the endothermic chemical reaction of the chemical substance in the endothermic end, and the heat absorbed by the endothermic end can be transmitted to the exothermic end to cause the exothermic chemical reaction of the chemical substance in the exothermic end.

[0010] Optionally, the air outlet pipeline in the oven is arranged in the air outlet pipeline, and the battery electrode coating and drying system further comprises a blast nozzle structure arranged in the oven, the blast nozzle structure comprises:

[0011] An outer shell is connected to the air inlet pipeline at one end, and the other end of the outer shell is provided with a through hole; and

[0012] The inner shell is arranged in the outer shell, and the inner shell is formed with an air extraction channel. One end of the air extraction channel is connected to the air outlet pipeline, and the other end of the air extraction channel points to the through hole. The air blowing channel is formed between the outer side surface of the inner shell and the inner side surface of the outer shell.

[0013] Optionally, the gas flow rate in the air extraction channel is greater than the gas flow rate in the air blowing channel.

[0014] Optionally, two air blowing channels are formed between the outer side surface of the inner shell and the inner side surface of the outer shell.

[0015] Optionally, the gas flow rates in the two air blowing channels are the same.

[0016] Optionally, a plurality of air nozzle structures are provided, and the air inlet pipeline in the oven is provided with a plurality of ports corresponding to the plurality of air nozzle structures. The air outlet pipeline in the oven is provided with a plurality of ports corresponding to the plurality of air nozzle structures.

[0017] Optionally, the heat exchanger comprises:

[0018] The first gas pipeline comprises a first pipe body, a second pipe body and a plurality of first fins. The plurality of first fins are arranged between the first pipe body and the second pipe body, and the plurality of first fins are arranged in layers with a spacing.

[0019] The second gas pipeline comprises a third pipe body, a fourth pipe body and a plurality of second fins. The plurality of second fins are arranged between the third pipe body and the fourth pipe body, and the plurality of second fins are arranged in layers with a spacing. The plurality of first fins and the plurality of second fins are arranged in layers with a spacing.

[0020] Optionally, the chemical heat pump structure adopts a calcium sulfate-water reaction system.

[0021] Optionally, a temperature sensor and a heater are further arranged on the air outlet pipeline between the heat release end and the oven.

[0022] Optionally, the pole piece generates NMP gas, and an NMP recovery device is arranged on the air outlet pipeline away from the heat exchanger side of the heat absorption end.

[0023] The battery electrode coating and drying system provided by the application has the beneficial effects that, compared with the prior art, the battery electrode coating and drying system of the application comprises an oven, an air inlet pipeline, an air outlet pipeline, a heat exchanger and a chemical heat pump structure, the air inlet pipeline is communicated with a first gas passage, the air outlet pipeline is communicated with a second gas passage, heat exchange is performed between the first gas passage and the second gas passage, and the heat of high-temperature waste gas in the air outlet pipeline is preliminarily exchanged to the gas in the air inlet pipeline; the chemical heat pump structure can also convert the low-grade heat of the gas in the air outlet pipeline into high-grade heat through a chemical reaction, the recovery rate of the recovered energy by the chemical reaction is high, the high-grade heat is used to heat the gas in the air inlet pipeline again, the heat recovery and utilization of the high-temperature waste gas are realized, the energy utilization rate is improved, and energy waste is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0025] Figure 1 A front view structural schematic diagram of the battery electrode coating and drying system provided by the embodiment of the application is provided.

[0026] Figure 2 A three-dimensional structural schematic diagram of the air nozzle and the pole piece of the battery electrode coating and drying system provided by the embodiment of the application is provided.

[0027] Figure 3 An internal structural schematic diagram of the air nozzle of the battery electrode coating and drying system provided by the embodiment of the application is provided.

[0028] Figure 4 A sectional view structural schematic diagram of the air nozzle of the battery electrode coating and drying system provided by the embodiment of the application is provided.

[0029] Figure 5 A three-dimensional structural schematic diagram of the heat exchanger of the battery electrode coating and drying system provided by the embodiment of the application is provided.

[0030] Figure 6 A gas flow path schematic diagram in the heat exchanger of the battery electrode coating and drying system provided by the embodiment of the application is provided.

[0031] BRIEF DESCRIPTION OF DRAWINGS

[0032] 1, oven; 2, air inlet pipeline; 3, air outlet pipeline; 4, heat exchanger; 410, first gas pipeline; 411, first pipe body; 412, second pipe body; 413, first fin; 420, second gas pipeline; 421, third pipe body; 422, fourth pipe body; 423, second fin; 5, chemical heat pump structure; 510, heat absorption end; 520, heat release end; 6, tuyere structure; 610, outer shell; 611, through hole; 620, inner shell; 630, air suction channel; 640, air blowing channel; 7, heater; 8, NMP recovery device; 9, pole piece. DETAILED DESCRIPTION

[0033] In order to make the above objectives, features and advantages of the present application more apparent, specific embodiments of the present application are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a number of ways other than those described herein, and the skilled person can make similar improvements without departing from the scope of the present application, so the present application is not limited to the specific embodiments disclosed below.

[0034] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0035] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0036] In the present application, unless specifically defined otherwise, the terms "mounting", "connected", "connecting", "fixed", and "fixing" should be construed as broad terms, for example, can be fixed connection, can also be detachable connection, or integrated; can be mechanical connection, can also be electrical connection; can be direct connection, can also be indirect connection through an intermediate medium, can be the internal communication of two elements or the interaction relationship of two elements, unless otherwise explicitly defined. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0037] In the present application, unless specifically defined otherwise, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "under" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0038] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there can be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there can be a middle element. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are for illustrative purposes only and are not the only implementation.

[0039] The embodiment of the present application provides a battery electrode coating and drying system, please see Figures 1 to 6The battery electrode coating and drying system comprises an oven 1, an air inlet pipeline 2, an air outlet pipeline 3, a heat exchanger 4 and a chemical heat pump structure 5. The pole piece 9 is transmitted in the oven 1. One end of the air inlet pipeline 2 is communicated with the oven 1, and the air inlet pipeline 2 is used for conveying hot air to the pole piece 9. One end of the air outlet pipeline 3 is communicated with the oven 1, and the air outlet pipeline 3 is used for discharging high-temperature waste gas in the oven 1. The heat exchanger 4 has a first gas passage and a second gas passage capable of exchanging heat. The air inlet pipeline 2 is communicated with the first gas passage, and the air outlet pipeline 3 is communicated with the second gas passage. The chemical heat pump structure 5 has an endothermic end 510 and an exothermic end 520. The endothermic end 510 is arranged on the air outlet pipeline 3 away from the oven 1 of the heat exchanger 4. The exothermic end 520 is arranged on the air inlet pipeline 2 between the heat exchanger 4 and the oven 1. The heat of the air outlet pipeline 3 can cause the chemical substance in the endothermic end 510 to have an endothermic chemical reaction. The heat absorbed by the endothermic end 510 can be transmitted to the exothermic end 520, so that the chemical substance in the exothermic end 520 has an exothermic chemical reaction.

[0040] In the embodiment, the battery electrode coating and drying system comprises an oven 1, an air inlet pipeline 2, an air outlet pipeline 3, a heat exchanger 4 and a chemical heat pump structure 5. The air inlet pipeline 2 is communicated with the first gas passage, and the air outlet pipeline 3 is communicated with the second gas passage. The first gas passage and the second gas passage exchange heat, so that the heat of the high-temperature waste gas in the air outlet pipeline 3 is preliminarily exchanged to the gas in the air inlet pipeline 2. The chemical heat pump structure 5 can also convert the low-grade heat of the gas in the air outlet pipeline 3 into high-grade heat through a chemical reaction. The recovery rate of the recovered energy by the chemical reaction is high. The high-grade heat is used to heat the gas in the air inlet pipeline 2, so that the heat of the high-temperature waste gas is recycled and utilized, the utilization rate of energy is improved, and energy waste is reduced.

[0041] It can be understood that a large amount of NMP (N-Methylpyrrolidone) gas will be evaporated in the coating and drying process of the positive pole piece 9. The NMP gas has the properties of being flammable and explosive. If the concentration of the NMP gas in the oven 1 is too high, there is a risk of explosion.

[0042] In one embodiment, referring to Figures 2 to 4 , the air outlet pipeline 3 in the oven 1 is arranged in the air outlet pipeline 3. The battery electrode coating and drying system further comprises a blast nozzle structure 6 arranged in the oven 1. The blast nozzle structure 6 comprises an outer shell 610 and an inner shell 620. One end of the outer shell 610 is connected to the air inlet pipeline 2. The other end of the outer shell 610 is provided with a through hole 611. The inner shell 620 is arranged in the outer shell 610. The inner shell 620 forms an air suction passage 630. One end of the air suction passage 630 is connected to the air outlet pipeline 3. The other end of the air suction passage 630 points to the through hole 611. A gas blowing passage 640 is formed between the outer side surface of the inner shell 620 and the inner side surface of the outer shell 610.

[0043] By the above arrangement, high-speed hot air is blown from the blowing channel 640 to the surface of the pole piece 9 to heat the pole piece 9, and more NMP gas is generated at the heated surface of the pole piece 9. Since the other end of the suction channel 630 points to the through hole 611, most of the NMP gas generated during the drying of the pole piece 9 is timely sucked away by the suction channel 630, avoiding excessive escape of NMP gas into the oven 1, thereby achieving the effect of reducing the concentration of NMP gas in the oven 1 and reducing the safety hazard caused by the large accumulation of NMP gas in the oven 1.

[0044] In one embodiment, the gas flow rate in the suction channel 630 is greater than the gas flow rate in the blowing channel 640. Specifically, the suction efficiency of the suction channel 630 is slightly greater than the blowing efficiency of the blowing channel 640, which can avoid affecting the drying efficiency and avoid excessive escape of NMP gas into the oven 1.

[0045] In one embodiment, please refer to Figure 3 and Figure 4 The outer side surface of the inner shell 620 and the inner side surface of the outer shell 610 form two oppositely arranged blowing channels 640, which improves the drying efficiency.

[0046] In one embodiment, the gas flow rates in the two blowing channels 640 are the same, so that the force on both sides of the air nozzle structure 6 is uniform and the stability is good.

[0047] In one embodiment, please refer to Figure 1 The air nozzle structure 6 is provided with a plurality of air nozzle structures 6, and the air inlet pipeline 2 in the oven 1 is provided with a plurality of ports corresponding to the plurality of air nozzle structures 6. The air outlet pipeline 3 in the oven 1 is provided with a plurality of ports corresponding to the plurality of air nozzle structures 6.

[0048] Specifically, the plurality of air nozzle structures 6 are uniformly arranged above the pole piece 9 along the conveying direction of the pole piece 9, avoiding long-term retention of hot air in a certain part of the oven 1, and the temperature of each part of the oven 1 is relatively uniform, improving the drying effect.

[0049] In one embodiment, please refer to Figure 5The heat exchanger 4 comprises a first gas pipeline 410 and a second gas pipeline 420. The first gas pipeline 410 comprises a first pipe body 411, a second pipe body 412, and a plurality of first fins 413 arranged between the first pipe body 411 and the second pipe body 412. The plurality of first fins 413 are arranged in a staggered manner. The second gas pipeline 420 comprises a third pipe body 421, a fourth pipe body 422, and a plurality of second fins 423 arranged between the third pipe body 421 and the fourth pipe body 422. The plurality of second fins 423 are arranged in a staggered manner. The plurality of first fins 413 and the plurality of second fins 423 are arranged in a staggered manner. The contact area between the first gas pipeline 410 and the second gas pipeline 420 is increased, thereby improving the heat exchange efficiency.

[0050] Further, the first fins 413 and the second fins 423 are made of high-thermal-conductivity materials.

[0051] In an embodiment, the chemical heat pump structure 5 adopts a calcium sulfate-water reaction system.

[0052] Specifically, the dehydration reaction of calcium sulfate hemihydrate occurs in the heat absorption end 510, and heat is absorbed to form calcium sulfate and water vapor. The water vapor is transported from the heat absorption end 510 to the heat release end 520. The calcium sulfate in the heat release end 520 is combined with the water vapor to release a large amount of heat.

[0053] In an embodiment, referring to Figure 1 A temperature sensor and a heater 7 are further arranged on the gas outlet pipeline 3 between the heat release end 520 and the oven 1.

[0054] In this way, the temperature of the air in the air inlet pipeline is monitored by the temperature sensor. If the temperature of the air in the air inlet pipeline is too low, the air is heated again by the heater 7 to ensure that the temperature of the air entering the oven 1 meets the preset requirements.

[0055] In an embodiment, referring to Figure 1 The NMP gas is generated by the pole piece 9. An NMP recovery device 8 is arranged on the gas outlet pipeline 3 away from the heat exchanger 4 on the side of the heat absorption end 510. Specifically, the NMP recovery device 8 is a condensing device.

[0056] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as the combinations of the technical features do not contradict each other, they should be considered as within the scope of the present disclosure.

[0057] The above embodiments only express several implementation ways of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation to the patent scope of the application. It should be pointed out that for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, which all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A battery electrode coating and drying system, characterized by, The battery electrode coating drying system comprises: an oven, inside which a plurality of electrode sheets are conveyed; an air inlet pipe, one end of which is connected to the oven, and which is used to convey hot air to the electrode sheets; an air outlet pipe, one end of which is connected to the oven, and which is used to discharge high-temperature exhaust gas in the oven; a heat exchanger, which has a first gas passage and a second gas passage capable of exchanging heat, the air inlet pipe is connected to the first gas passage, and the air outlet pipe is connected to the second gas passage; and a chemical heat pump structure, which has an endothermic end and an exothermic end, the endothermic end is arranged on the air outlet pipe away from the oven on the side of the heat exchanger, and the exothermic end is arranged on the air inlet pipe between the heat exchanger and the oven, the heat of the air outlet pipe can cause the chemical substances in the endothermic end to undergo an endothermic chemical reaction, and the heat absorbed by the endothermic end can be transferred to the exothermic end to cause the chemical substances in the exothermic end to undergo an exothermic chemical reaction. The heat exchanger comprises: a first gas pipe, which comprises a first pipe body, a second pipe body and a plurality of first fins, the plurality of first fins are arranged between the first pipe body and the second pipe body, and the plurality of first fins are arranged in a staggered manner; and a second gas pipe, which comprises a third pipe body, a fourth pipe body and a plurality of second fins, the plurality of second fins are arranged between the third pipe body and the fourth pipe body, and the plurality of second fins are arranged in a staggered manner, and the plurality of first fins and the plurality of second fins are arranged in a staggered manner. The air outlet pipe in the oven is arranged in the air outlet pipe, and the battery electrode coating drying system further comprises a blast nozzle structure arranged in the oven, the blast nozzle structure comprises:

2. The battery electrode coating and drying system of claim 1, wherein, an outer shell, one end of which is connected to the air inlet pipe, and the other end of which is provided with a through hole; and an inner shell arranged in the outer shell, the inner shell forms an air suction passage, one end of the air suction passage is connected to the air outlet pipe, the other end of the air suction passage points to the through hole, and a gas blowing passage is formed between the outer side surface of the inner shell and the inner side surface of the outer shell. The gas flow rate in the air suction passage is greater than the gas flow rate in the gas blowing passage.

3. The battery electrode coating and drying system of claim 2, wherein, The outer side surface of the inner shell and the inner side surface of the outer shell form two oppositely arranged gas blowing passages.

4. The battery electrode coating and drying system of claim 2, wherein, The gas flow rates in the two gas blowing passages are the same.

5. The battery electrode coating and drying system of claim 4, wherein, The blast nozzle structure is provided with a plurality of blast nozzle structures, the air inlet pipe in the oven is provided with a plurality of ports corresponding to the plurality of blast nozzle structures, and the air outlet pipe in the oven is provided with a plurality of ports corresponding to the plurality of blast nozzle structures.

6. The battery electrode coating and drying system of claim 2, wherein, The chemical heat pump structure adopts a calcium sulfate-water reaction system.

7. The battery electrode coating and drying system of any one of claims 1-6, wherein, A temperature sensor and a heater are further arranged on the air outlet pipe between the exothermic end and the oven.

8. The battery electrode coating and drying system of any one of claims 1-6, wherein, The electrode sheets produce NMP gas, and an NMP recovery device is arranged on the air outlet pipe away from the heat exchanger on the side of the endothermic end.

9. The battery electrode coating and drying system of any one of claims 1-6, wherein, ​

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