Pole piece drying equipment

Abstract

The utility model relates to the technical field of lithium batteries, in particular to pole piece drying equipment which comprises a material conveying mechanism, a drying chamber, a heating mechanism and a cooling and drying mechanism. The preheating unit, the heating and drying unit and the cooling unit are sequentially arranged on the material conveying mechanism in the conveying direction of the material conveying mechanism. The heating mechanism is installed on the drying chamber, and the output end of the heating mechanism communicates with the heating and drying unit. The cooling and drying mechanism is used for cooling and drying hot air exhausted by the preheating unit, and the output end of the cooling and drying mechanism communicates with the input end of the heating mechanism; hot air discharged by the heating and drying unit can only be discharged towards the cooling unit in a one-way mode, and the cooling unit is communicated with the discharging end of the preheating unit through a heat conveying pipe. According to the pole piece drying equipment, hot air overflowing in the drying process can be effectively utilized, and energy consumption needed by overall drying is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, in particular to a pole piece drying device. Background Art

[0002] Existing lithium battery pole piece drying equipment mainly uses hot air drying to dry the coated pole pieces. The main units in the drying equipment generally use multiple ovens arranged in sequence, and the membrane to be dried passes through each oven to achieve drying. During the use of existing lithium battery pole piece drying equipment, the overall energy consumption is large and the drying cost is high.

[0003] In view of such a situation, the patent with publication number CN116353200B discloses a battery pole piece drying system. In the drying process, the membrane to be dried first passes through each waste heat recovery oven in sequence, and then passes through each deep drying oven in sequence. The membrane to be dried completes the preliminary drying process in the waste heat recovery oven, and then undergoes deep drying in the deep drying oven. The combination of the two types of ovens can meet the drying requirements with a smaller number of ovens, thereby reducing energy consumption. However, after the deep drying oven receives the hot air, the hot air flows out from both ends of the deep drying oven. Since new hot air continuously enters the deep drying oven, its internal pressure increases, which will cause the entire drying process to lose some energy and increase the processing cost during the processing of lithium battery pole pieces. At the same time, the discharge of these hot air from the production workshop is likely to cause the entire production environment to heat up, reducing the comfort of workers and also partially affecting the production process. Therefore, how to use this part of the overflowed hot air is a problem that needs to be solved in the current lithium battery pole piece production. Utility Model Content

[0004] In order to overcome one of the deficiencies of the prior art, the purpose of the utility model is to provide a pole piece drying device, which can effectively utilize the hot air overflowed during the drying process and reduce the energy consumption required for overall drying.

[0005] In order to solve the above problems, the technical solutions adopted by the utility model are as follows:

[0006] A pole piece drying device comprises a material conveying mechanism, a drying chamber, a heating mechanism and a cooling and drying mechanism, wherein the drying chamber comprises a preheating unit, a heating and drying unit and a cooling unit, wherein the preheating unit, the heating and drying unit and the cooling unit are sequentially arranged on the material conveying mechanism along the conveying direction of the material conveying mechanism; the heating mechanism is installed on the drying chamber, and the output end of the heating mechanism is connected to the heating and drying unit; the cooling and drying mechanism is used to cool and dry the hot air discharged by the preheating unit, and the output end of the cooling and drying mechanism is connected to the input end of the heating mechanism; the hot air discharged by the heating and drying unit can only be discharged in one direction to the cooling unit, and the cooling unit is connected to one end of the preheating unit located at the discharge through a heat supply pipe.

[0007] Furthermore, the cooling and drying mechanism includes a reflux pipe, a condenser, a drying tank and a recovery tank, one end of the reflux pipe is connected to the end of the preheating unit located at the feed, the other end of the reflux pipe is connected to the condenser, the condenser is connected to the drying tank through a connecting pipe, and the drying tank is connected to the input end of the heating mechanism through an air supply pipe; the recovery tank is connected to the discharge end of the condenser, and a blower is provided on the connecting pipe.

[0008] Furthermore, the connecting pipe is connected to a fresh air pipe, and a purifier is arranged on the fresh air pipe.

[0009] Furthermore, a heat exchange section is provided on the air supply pipe, and the heat exchange section is arranged in the cooling unit and can exchange heat with the cooling unit.

[0010] Furthermore, the heating mechanism includes a fresh air chamber, a preheating chamber and a heating chamber which are connected in one direction in sequence, the output end of the air supply pipe is connected to the preheating chamber, a heating element is arranged in the heating chamber, the heating chamber is connected to the heating and drying unit through the air supply pipe, the fresh air chamber and the preheating chamber are connected by a pipeline, and the fresh air chamber is connected to the output end of the air supply pipe through an air inlet pipe.

[0011] Furthermore, the air supply pipe is located in the heating and drying unit and is provided with a plurality of nozzles, the nozzles are respectively arranged on both sides of the heating and drying unit in the conveying direction of the material conveying mechanism, the nozzles are provided with a plurality of spray holes, and the spray holes on all the nozzles on both sides are facing the material conveying mechanism.

[0012] Furthermore, the material conveying mechanism includes a frame and a plurality of groups of conveying rollers arranged on the frame, the frame is provided with a driver for driving the conveying rollers to rotate, and the preheating unit, the heating and drying unit and the cooling unit are all covered on the frame.

[0013] Furthermore, a one-way feeding slit is provided between the preheating unit and the heating and drying unit, and the pole piece passes through the one-way feeding slit.

[0014] Compared with the prior art, the beneficial effects of the present invention are:

[0015] The utility model provides an electrode drying device that improves the drying chamber on the basis of the existing hot air drying equipment, and designs the drying chamber into three stages, which correspond to the three different processing stages of the electrode. Such a setting can reduce energy consumption to the greatest extent and realize the reasonable allocation of energy. The hot air exhausted by the heating and drying unit can be sent to the preheating unit for utilization after passing through the cooling unit, thereby realizing the proper utilization of energy. In addition, the hot air exhausted by the preheating unit is cooled and dried by the cooling and drying mechanism, which can effectively remove harmful substances in the hot air. At the same time, this part of the hot air can also be recycled and reused to avoid its external discharge, further reducing energy consumption losses.

[0016] The utility model is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a side view of an embodiment of the utility model;

[0018] Figure 2 It is a top view of an embodiment of the utility model;

[0019] Figure 3 It is a connection structure diagram of a drying chamber, a heating mechanism and a cooling and drying mechanism in an embodiment of the utility model.

[0020] Description of Figure Numbers:

[0021] Material conveying mechanism 10, frame 11, conveying roller 12;

[0022] Drying chamber 20, preheating unit 21, heating and drying unit 22, cooling unit 23;

[0023] Heating mechanism 30, fresh air chamber 31, preheating chamber 32, heating chamber 33, air supply pipe 34, pipeline 35, air inlet pipe 36, nozzle 37;

[0024] Cooling and drying mechanism 40, reflux pipe 41, condenser 42, drying tank 43, recovery tank 44, connecting pipe 45, air supply pipe 46, fresh air pipe 48, purifier 49, heat exchange section 4a. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0026] Reference Figures 1 to 3 The electrode drying equipment shown in the figure includes a material conveying mechanism 10, a drying chamber 20, a heating mechanism 30 and a cooling and drying mechanism 40, the drying chamber 20 includes a preheating unit 21, a heating and drying unit 22 and a cooling unit 23, the preheating unit 21, the heating and drying unit 22 and the cooling unit 23 are sequentially arranged on the material conveying mechanism 10 along the conveying direction of the material conveying mechanism 10; the heating mechanism 30 is installed on the drying chamber 20, and the output end of the heating mechanism 30 is connected to the heating and drying unit 22; the cooling and drying mechanism 40 is used to cool and dry the hot air discharged by the preheating unit 21, and the output end of the cooling and drying mechanism 40 is connected to the input end of the heating mechanism 30; the hot air discharged by the heating and drying unit 22 can only be discharged in one direction to the cooling unit 23, and the cooling unit 23 is connected to one end of the preheating unit 21 located at the discharge through a heat supply pipe 24.

[0027] Among them, the preheating unit 21, the heating and drying unit 22 and the cooling unit 23 are three independent spaces. The cooling unit 23 is actually a space where the temperature gradually decreases along the conveying direction of the material conveying mechanism 10. Therefore, in the actual production process, the hot air discharged from the heating and drying unit 22 to the cooling unit 23 is also discharged along the conveying direction of the material conveying mechanism 10, and the hot air output end of the cooling unit 23 is set at one end of the material discharge. In addition, it should be noted that in the actual production process, the actual temperature of the cooling unit 23 is higher than that of the preheating unit 21, which is formed by the structural arrangement, and its main function is to cool the heated electrode. The cooling of the electrode needs to be gradually cooled, so the cooling unit 23 can also play the role of an insulation box; furthermore, the cooling unit 23 can also recycle the heat transferred by the heating and drying unit 22, so it can achieve three goals at one stroke.

[0028] It should be supplemented that the material conveying mechanism 10 is a conventional clamping roller structure, which is mainly used for clamping and conveying the electrode, and therefore, its changes in form are relatively few during use. In one embodiment of the present application, the material conveying mechanism 10 includes a frame 11 and a plurality of groups of conveying rollers 12 arranged on the frame 11, and the frame 11 is provided with a driver for driving the conveying rollers 12 to rotate, and the preheating unit 21, the heating and drying unit 22 and the cooling unit 23 are all covered on the frame 11. Among them, the driver is a driving motor, and multiple adjacent conveying rollers 12 can be driven by the same driver, and can be driven to rotate by a chain or a synchronous belt. It should be noted that the conveying rollers 12 located in the corresponding areas of the heating and drying unit 22 and the cooling unit 23 are actually distributed in a serpentine shape, which can increase the residence time of the electrode in the above two areas and ensure the treatment effect.

[0029] The electrode drying equipment improves the drying chamber 20 on the basis of the existing hot air drying equipment, and designs the drying chamber 20 into three stages, corresponding to the three different processing stages of the electrode. Such a setting can reduce energy consumption to the greatest extent and realize the reasonable allocation of energy. The hot air discharged by the heating and drying unit 22 can be sent to the preheating unit 21 for utilization after passing through the cooling unit 23, realizing the energy utilization. In addition, the hot air discharged by the preheating unit 21 is cooled and dried by the cooling and drying mechanism 40, which can effectively remove harmful substances in the hot air. At the same time, this part of the hot air can also be recycled and reused to avoid its external discharge, further reducing energy consumption loss.

[0030] See also Figure 2 , since the NMP in the coating material on the electrode will volatilize outwards during the heating and drying process, in order to better recover the volatilized NMP and reduce environmental pollution. In one embodiment of the present application, the cooling and drying mechanism 40 includes a reflux pipe 41, a condenser 42, a drying tank 43 and a recovery tank 44, one end of the reflux pipe 41 is connected to the end of the preheating unit 21 located at the feed, and the other end of the reflux pipe 41 is connected to the condenser 42, the condenser 42 is connected to the drying tank 43 through a connecting pipe 45, and the drying tank 43 is connected to the input end of the heating mechanism 30 through an air supply pipe 46; the recovery tank 44 is connected to the discharge end of the condenser 42, and a blower 47 is provided on the connecting pipe 45. Among them, the boiling point of NMP is 202°C. Therefore, in the actual process, the condensation temperature of the condenser 42 is higher than the normal temperature. Therefore, the condensed air still contains a large amount of heat. Therefore, in order to continue to recycle this part of the heat, in this application, after the drying tank 43 is dried, the dried hot air is connected to the input end of the heating mechanism 30 through the air supply pipe 46, thereby realizing the recovery and utilization of part of the heat energy of the hot air.

[0031] Furthermore, when the internal pressure of the entire drying system decreases, the cooling and drying mechanism 40 needs to increase the air supply. For this reason, in some embodiments, the connecting pipe 45 is connected to a fresh air pipe 48, and a purifier 49 is provided on the fresh air pipe 48. The main purpose of the purifier 49 is to prevent harmful components in the outside air from entering the entire drying system and protect the normal production of the electrode.

[0032] In some embodiments, in order to reduce the temperature in the cooling unit 23 more quickly and reasonably utilize the heat in the cooling unit 23, while increasing the temperature of the air entering the heating mechanism 30, in one embodiment of the present application, a heat exchange section 4a is provided on the air delivery pipe 46, and the heat exchange section 4a is provided in the cooling unit 23 and can exchange heat with the cooling unit 23. In fact, the heat exchange section 4a and the cooling unit 23 constitute a heat exchange system. More specifically, the direction of the heat exchange section 4a in the cooling unit 23 is opposite to the conveying direction of the material conveying mechanism 10, which can effectively increase the temperature of the air delivered by the heat exchange section 4a.

[0033] See also Figure 1 and Figure 3 In one embodiment of the present application, in order to improve the efficiency of the entire heating and to adapt to the low-temperature hot air output by the above-mentioned air supply pipe 46, the heating mechanism 30 includes a fresh air chamber 31, a preheating chamber 32 and a heating chamber 33 which are connected in one direction in sequence. The output end of the air supply pipe 46 is connected to the preheating chamber 32, and a heating element is arranged in the heating chamber 33. The heating chamber 33 is connected to the heating and drying unit 22 through the air supply pipe 34. The fresh air chamber 31 and the preheating chamber 32 are connected through a pipe 35, and the fresh air chamber 31 is connected to the output end of the air supply pipe 46 through an air inlet pipe 36. Among them, the preheating chamber 32 is actually a cache space, and a heating element can be arranged inside it, while the fresh air chamber 31 is mainly used for standby or buffering more gas sent by the air supply pipe 46 to balance the air pressure. The heating element can be preferably an electric heating wire in the present application, which is not shown in the figure. A control valve body is arranged between the air supply pipe 34, the air inlet pipe 36 and the pipe 35, so as to facilitate the control of on and off.

[0034] In actual use, in order to improve the drying effect, the pole pieces in the present application are distributed in an up-and-down serpentine shape in the heating and drying unit 22. Therefore, in order to increase the contact time and opportunity between the pole pieces and the hot air, the air supply pipe 34 is located in the heating and drying unit 22 and is provided with a plurality of nozzles 37. The nozzles 37 are respectively arranged on both sides of the heating and drying unit 22 in the conveying direction of the material conveying mechanism 10. The nozzles 37 are provided with a plurality of spray holes, and the spray holes on all the nozzles 37 on both sides are facing the material conveying mechanism 10. The nozzles 37 are arranged in parallel in multiple groups and are parallel to the material conveying mechanism 10.

[0035] In the above embodiment, in order to prevent the hot air in the heating and drying unit 22 from entering the preheating unit 21, a one-way feeding gap is provided between the preheating unit 21 and the heating and drying unit 22, and the electrode piece passes through the one-way feeding gap. A one-way air supply channel can be provided between the heating and drying unit 22 and the cooling unit 23 to realize hot air delivery. At the same time, the sealing requirements between the two spaces are relatively low.

[0036] The above-mentioned implementation modes are only preferred implementation modes of the present invention, and cannot be used to limit the protection scope of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A pole piece drying device, characterized in that: include A material conveying mechanism, which is used to clamp and convey the electrode; A drying chamber, comprising a preheating unit, a heating and drying unit and a cooling unit, wherein the preheating unit, the heating and drying unit and the cooling unit are sequentially arranged on the material conveying mechanism along the conveying direction of the material conveying mechanism; A heating mechanism, which is installed on the drying chamber, and an output end of the heating mechanism is connected to the heating and drying unit; A cooling and drying mechanism, which is used to cool and dry the hot air exhausted by the preheating unit, wherein the output end of the cooling and drying mechanism is connected to the input end of the heating mechanism; The hot air discharged from the heating and drying unit can only be discharged in one direction to the cooling unit, and the cooling unit is connected to the end of the preheating unit located at the discharge end through a heat supply pipe.

2. The electrode drying device according to claim 1, characterized in that: The cooling and drying mechanism includes a reflux pipe, a condenser, a drying tank and a recovery tank. One end of the reflux pipe is connected to the end of the preheating unit located at the feed, and the other end of the reflux pipe is connected to the condenser. The condenser is connected to the drying tank through a connecting pipe, and the drying tank is connected to the input end of the heating mechanism through an air supply pipe; the recovery tank is connected to the discharge end of the condenser, and a blower is provided on the connecting pipe.

3. The electrode drying device according to claim 2, characterized in that: The connecting pipe is connected with a fresh air pipe, and a purifier is arranged on the fresh air pipe.

4. The electrode drying device according to claim 2, characterized in that: The air supply pipe is provided with a heat exchange section, which is arranged in the cooling unit and can exchange heat with the cooling unit.

5. The electrode drying device according to claim 2, characterized in that: The heating mechanism includes a fresh air chamber, a preheating chamber and a heating chamber which are connected in one direction in sequence. The output end of the air supply pipe is connected to the preheating chamber. A heating element is arranged in the heating chamber. The heating chamber is connected to a heating and drying unit through an air supply pipe. The fresh air chamber and the preheating chamber are connected through a pipeline. The fresh air chamber is connected to the output end of the air supply pipe through an air inlet pipe.

6. The electrode drying device according to claim 5, characterized in that: The air supply pipe is located in the heating and drying unit and is provided with a plurality of nozzles, and the nozzles are respectively arranged on both sides of the heating and drying unit in the conveying direction of the material conveying mechanism. The nozzles are provided with a plurality of spray holes, and the spray holes on all the nozzles on both sides are facing the material conveying mechanism.

7. The electrode drying device according to any one of claims 1 to 6, characterized in that: The material conveying mechanism comprises a frame and a plurality of conveying rollers arranged on the frame. The frame is provided with a driver for driving the conveying rollers to rotate. The preheating unit, the heating and drying unit and the cooling unit are all covered on the frame.

8. The electrode drying device according to claim 1, characterized in that: A one-way feeding slit is provided between the preheating unit and the heating and drying unit, and the pole piece passes through the one-way feeding slit.

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