CN105499093A - Coating and drying method for pole belts, pole piece preparation method and pole piece preparation system - Google Patents

Abstract

The invention relates to the electrode field, in particular to a coating and drying method for pole belts, a pole piece preparation method and a pole piece preparation system. The coating and drying method comprises the steps that the pole belts are conveyed in a tension-controllable mode, the two surfaces of the pole belts are coated with slurry simultaneously in the conveying process and then are dried simultaneously in a suspension type drying oven, and the tension of the pole belts and the wind force in the suspension type drying oven are controlled together so that the pole belts can penetrate through the suspension type drying oven in a suspension mode. The coating and drying step in the pole piece preparation method adopts the coating and drying method. The pole piece preparation system comprises a coating and drying device, and the coating and drying device comprises a tension control correction module, a double-surface coating module, the suspension type drying oven and a roll-in type tension conduction band module, wherein the tension control correction module, the roll-in type tension conduction band module and the suspension type drying oven jointly control the pole belts to penetrate through the suspension type drying oven in a suspension mode. The production efficiency of the coating and drying method, the pole piece preparation method and the pole piece preparation system is high.

Description

Coating and drying method for pole strip, pole piece preparation method and pole piece preparation system

technical field

The present invention relates to the field of electrodes, in particular to a coating and drying method for pole strips, a pole piece preparation method and a pole piece preparation system, and more particularly to a coating and drying method for pole strips used for making lithium-ion battery pole pieces. A dry method, a lithium ion battery pole piece preparation method and a lithium ion battery pole piece preparation system.

Background technique

At present, general lithium-ion battery pole pieces need to go through four processes of coating, rolling, slitting, and sheet production. In order to improve performance, the production of high-performance power lithium-ion battery pole pieces often requires multi-layer coating, and then rolls Pressing, cutting, sheeting and other processes. At present, each process is completed by using separate equipment: coating machine, roller press, slitting machine, and sheet making machine. Between each process, each process needs to be wound and unwound. The connection of the process needs to be completed manually. Among them, there are the following disadvantages: ① many processes, many personnel involved, and difficult automation, which have a great impact on the consistency of products, and the consistency of lithium-ion battery products is extremely important; ② non-stop winding and unwinding, resulting in extreme After the film is completed, there is a certain warpage, which has a certain impact on product performance and has caused certain troubles to the subsequent lamination; ③The non-stop winding and unwinding prolongs the logistics line of the production line, resulting in logistics and The high labor cost has a great impact on the current cost-sensitive lithium-ion power battery.

Patent CN102569731 discloses a pole piece coating, rolling and slitting integrated machine, wherein the front coating mechanism is located between the biaxial unwinding mechanism and the double-layer drying mechanism, and the pole strip enters the front walking mechanism after unwinding It is coated on the front side and then enters the lower drying unit. The reverse coating mechanism is located on the discharge side of the lower drying unit of the double-deck drying mechanism. After being dried by the lower drying unit, the polar belt enters the reverse coating mechanism for reverse coating and then enters the upper drying unit. That is, coating and drying are performed on only one side. In this way, the preparation time of the pole piece is longer, and the efficiency of the production process is not high.

Contents of the invention

(1) Technical problems to be solved

The technical problem to be solved by the present invention is to provide a coating and drying method for pole strips, a pole piece preparation method and a pole piece preparation system with high production efficiency.

(2) Technical solution

In order to solve the above technical problems, the present invention provides a coating and drying method for the pole belt, which includes the following steps: the tension controllable transmission of the pole belt, and in the transmission process, the double pole belt first The slurry is coated on both sides at the same time, and then both sides of the pole strip are dried in the suspension oven at the same time; wherein, the tension control of the pole strip and the wind force in the suspension oven jointly control the suspension of the pole strip through the suspension oven.

According to the invention, the pole strip is deflected before it is coated.

According to the invention, coating can be gravure coating, spray coating or extrusion coating.

Another aspect of the present invention provides a pole piece preparation method, including the following steps performed in sequence: an unwinding step; a coating and drying step, using any one of the above-mentioned coating and drying methods for pole strips to carry out Coating and drying; rolling step, tension and position controllable conveying of the dried pole strip, during which the pole strip is rolled; sheeting step, tensioning the rolled pole strip and position controllable conveying, then cutting the pole strip to make pole pieces, and finally collecting the finished pole pieces; wherein, the step of coating and drying is performed at least once.

Another aspect of the present invention provides a pole piece preparation method, which includes the following steps performed in sequence: an unwinding step; a coating and drying step, using any one of the above-mentioned coating and drying methods for the pole strip to coat the pole strip Coating and drying; the rolling step, the tension and position controllable transmission of the dried pole belt, during the transmission process, the pole belt is rolled; the coating and drying step, using any one of the above-mentioned claims In the method of coating and drying the pole strip, the pole strip after rolling is coated and dried again; in the film making step, the tension and position of the dried pole strip are conveyed in a controlled manner, and then the pole strip is cut cutting to make pole pieces, and finally collecting the finished pole pieces; wherein, the coating and drying step performed before the rolling step is performed at least once.

Another aspect of the present invention provides a pole piece preparation system, which includes at least one set of coating and drying devices, and the coating and drying device includes: a tension control and deviation correction module for correcting and tension controlling the pole belt, A double-sided coating module for simultaneous coating of slurry on both sides of the pole belt, at least one suspension oven for simultaneously drying both sides of the pole belt, and a roller tensioner for providing traction to the pole belt Guide belt module; among them, the tension control deviation correction module, double-sided coating module, suspension oven and roller tension belt guide module are arranged in sequence, and the tension control deviation correction module, roller pressure tension belt module and The suspension oven collectively controls the suspension of the pole strips through the suspension oven.

According to the present invention, it also includes: an unwinding device arranged on the feeding side of the coating and drying device, the unwinding device includes an air expansion shaft, an active unwinding servo mechanism, a tension detection device, and a deviation correction mechanism.

According to the present invention, it also includes: a rolling device for rolling the pole belt and a sheet-making device for making the pole belt into a pole sheet; when a coating drying device is provided, the rolling device and the sheet-making device are arranged in sequence On the discharge side of the coating and drying device; when multiple coating and drying devices are provided, the rolling device and the sheet-making device are sequentially arranged on the discharge side of the last coating and drying device, or the rolling device is arranged on the discharge side of the last coating and drying device. The feed side of the last coating and drying device and the tablet making device are arranged on the discharge side of the coating and drying device.

According to the present invention, the rolling device includes a tension control deviation correction module, a rolling module, and a rolling tension belt module arranged in sequence; the film making device includes a tension control deviation correction module, a slicing module, a film receiving mod.

According to the present invention, the tension control deviation correction module includes a tension control mechanism, a pole belt buffer adjustment mechanism, and a deviation correction execution mechanism.

According to the present invention, the rolling tension belt module includes a pair of pressure rollers, a bearing seat, a gear set and a servo driver; wherein, both ends of the pressure roller are rotatably supported on the bearing seat, and the servo driver drives the gear set movement, the gear set drives the pair of pressure rollers to rotate synchronously.

(3) Beneficial effects

The technical scheme of the present invention has the following advantages:

The coating and drying method for the pole belt of the present invention comprises the following steps: the tension of the pole belt is conveyed under controllability; In the type oven, both sides of the pole belt are dried at the same time; wherein, the tension control of the pole belt and the wind force in the suspension oven jointly control the suspension of the pole belt through the suspension oven. With this coating and drying method, both sides of the pole strip can be coated at the same time, and the pole strip can be controlled by combining the tension control of the pole strip and the wind force in the suspension oven, so that the pole strip can be suspended through the Suspension oven, so as to realize the drying of both sides of the pole belt at the same time. Thus, both sides of the pole strip are coated and dried at the same time, which improves the efficiency of the production process.

In the pole piece preparation method of the present invention, the above-mentioned coating and drying method is used to coat and dry the pole strip, thereby improving the efficiency of the production process.

The pole sheet preparation system of the present invention uses a double-sided coating module to simultaneously coat both sides of the pole strip, and controls the suspension of the pole strip jointly by a tension control deviation correction module, a roller-type tension belt guide module, and a suspension oven. Passing through the suspension oven, it is possible to dry both sides of the pole belt at the same time. Thus, both sides of the pole strip are coated and dried at the same time, which improves the efficiency of the production process.

Description of drawings

Fig. 1 is the structural representation of the first embodiment of pole piece preparation system of the present invention;

Fig. 2 is a partial schematic view of the unwinding device in the pole piece preparation system shown in Fig. 1;

Fig. 3 is a partial schematic view of the first coating and drying device in the pole piece preparation system shown in Fig. 1;

Fig. 4 is a schematic front view of the roll-pressed tension belt module in the first coating and drying device shown in Fig. 3;

Fig. 5 is a partial schematic diagram of a rolling device and a sheet-making device in the pole piece preparation system shown in Fig. 1;

Fig. 6 is a schematic structural view of the second embodiment of the pole piece preparation system of the present invention. In the picture:

1: unwinding device; 2: first coating and drying device; 3: second coating and drying device; 4: third coating and drying device; 5: rolling device; 6: film making device; 21, 31, 41, 51, 61: Tension control correction module; 22, 32, 42: Double-sided coating module; 23, 33, 43: Suspension oven; 24, 34, 44, 53: Roller tension guide Belt module; 52: Rolling module; 62: Slicing module; 63: Film receiving module; 241: Bearing seat; 242: Pressure roller; 243: Gear set: 244: Servo drive.

detailed description

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Embodiment 1 of pole piece preparation system

Referring to Figures 1 to 5, in this embodiment, the pole piece preparation system includes at least one set of coating and drying devices, and each coating and drying device includes a tension control deviation correction module and a double-sided coating module arranged in sequence. , at least one suspension oven, and a roll-pressed tension belt module. Among them, the tension control correction module is used to correct the deviation and tension control of the pole belt, the double-sided coating module is used to coat the slurry on both sides of the pole belt simultaneously, and the suspension oven is used to simultaneously coat both sides of the pole belt. Drying is carried out, and the roller-pressed tension belt module is used to provide traction for the pole belt. The tension control correction module, the roller pressure belt guide module and the suspension oven jointly control the suspension of the pole belt through the suspension oven. In other words, through the tension control of the tension control correction module and the traction force exerted by the roller tension belt guide module on the pole belt, the tension of the pole belt can be adjusted, and then the tension of the pole belt can be transmitted in a controllable manner. Above, combined with the wind in the suspension oven, it can ensure that the pole belt is suspended through the suspension oven. In this way, it is possible to simultaneously coat and dry both sides of the pole strip, thereby improving the efficiency of the production process. In addition, the way of coating the front and back (both sides) of the pole strip at the same time can improve the consistency of the performance of the pole piece made from the pole strip.

In this embodiment, the pole piece preparation system is used to prepare lithium ion battery pole pieces.

Further, in this embodiment, the pole piece preparation system further includes an unwinding device 1 , a rolling device 5 and a sheet making device 6 .

Referring to Fig. 1, the unwinding device 1 is arranged on the feed side of the coating drying device, and the rolling device 5 and the sheet making device 6 are arranged successively on the discharging side of the coating drying device, that is, the unwinding device 1, the coating and drying device The drying device, the rolling device 5 and the sheet making device 6 are arranged in sequence. During the preparation process, the pole strip is placed in the unwinding device 1, and then enters the coating and drying device for coating slurry and drying, and then the dried pole strip enters the rolling device 5 to be rolled, The rolled pole strip enters the sheet making device 6 to make pole pieces.

Further, with reference to Fig. 1, the unwinding device 1, the coating and drying device, the rolling device 5 and the sheet making device 6 are specifically described along the conveying direction of the pole belt, wherein, in this embodiment, three coating devices are sequentially arranged. The coating and drying devices are respectively the first coating and drying device 2, the second coating and drying device 3 and the third coating and drying device 4.

1 and 2, the unwinding device 1 includes an air expansion shaft, an active unwinding servo mechanism, a tension detection device, and a deviation correction mechanism. After the pole tape is put into the unwinding device 1, it is gradually sent to the tension control and deviation correction module 21 in the first coating and drying device 2, and then continues to be sent through the double-sided coating module 22, the suspension oven 23, Roller type tension belt module 24. It can be understood that the joint cooperation of the unwinding device 1, the tension control deviation correction module and the roller tension belt guide module further performs tension control and deviation correction on the pole belt, that is, the tension and position controllable transmission of the pole belt can be carried out.

1 and 3, in the first coating and drying device 2, the tension control and deviation correction module 21 includes a tension control mechanism, a pole band buffer adjustment mechanism, and a deviation correction actuator, which has a pole band buffer adjustment function and can realize front and rear alignment. Extremely controlled and relatively separated under force. The double-sided coating module 22 can be a gravure coating device or a spray coating device to realize the function of thin layer coating. In the suspension oven 23 , the pre-designed up and down blowing airflow can ensure that the pole belt passes through smoothly at the set position, and ensure that the coated slurry coating on the pole belt is dried. As shown in Figure 4, the rolling tension belt module 24 mainly includes a bearing housing 241, a pair of pressure rollers 242, a gear set 243 and a servo driver 244, wherein the two ends of the pressure roller 242 are rotatably supported on the bearings On the seat 241, the servo driver 244 drives the gear set 243 to move, and the gear set drives a pair of pressure rollers 242 to rotate synchronously. In the case of not bending the pole belt, the friction force between the pressure roller 242 and the pole belt provides traction force for the pole belt, so as to ensure that the pole belt advances smoothly under a certain tension. The material of the part where the pressure roller is in contact with the pole piece can be one of metal, rubber, plastic and fiber. The pole belt passes through the first coating and drying device 2 to form the first coating layer.

In the second coating and drying device 3, the tension control deviation correction module 31, the suspension oven 33 and the rolling tension belt guide module 34 are the same as the corresponding parts in the first coating and drying device 2, the only difference is that The double-sided coating module 32 in this second coating and drying device 3 is an extrusion coating mechanism, which can realize high viscosity and coating with a thickness of 50-300nm, and in order to cooperate with the double-sided coating module The coating parameters are dried by using a plurality of suspension ovens 33 connected in series. The pole belt passes through the second coating and drying device 3 to form a second coating layer above the first coating layer.

The tension control correction module 41, the double-sided coating module 42, the suspension oven 43 and the roller type tension belt module 44 in the third coating and drying device 4 are the same as those in the first coating and drying device 2. The corresponding parts are identical, and the pole belt passes through the third coating and drying device 4 to form a third coating layer above the second coating layer.

Referring to FIG. 1 and FIG. 5 , the rolling device 5 includes a tension control deviation correction module 51 , a rolling module 52 , and a rolling tension belt module 53 arranged in sequence. The tension control deviation correction module 51 and the roller tension belt guide module 53 are respectively the same as the tension control deviation correction module and the roller pressure tension belt guide module in the coating drying device, which realize the tension and position of the polar belt Controlled delivery. The rolling die set 52 includes a pair of rollers for rolling the pole strip after three times of coating and drying. The rolling die set 52 is hydraulically provided with calendering force to increase the surface density by thinning the coated pole strip, and the diameter of the roller is ≥500mm.

Referring to FIG. 1 and FIG. 5 , the film production device 6 includes a tension control and deviation correction module 61 , a slicing module 62 , and a film receiving module 63 arranged in sequence. The tension control and deviation correction module 61 is the same as the tension control and deviation correction module in the coating and drying device, which realizes the tension control and deviation correction of the pole belt, and then realizes the tension and position controllable transmission of the pole belt. The slicing module 62 can be a device for performing one of the slicing methods of metal die punching, laser die cutting, and shearing, wherein the pole strip is conveyed by the feeding mechanism before cutting, and the pole piece after cutting passes through the conveyor belt delivery. The receiving module 63 is a device for storing and transferring pole pieces matched with the slicing module 62, and may optionally be a frame-type box made of plastic or stainless steel. With the sheet making device 6 , there is no slitting process in the usual manufacturing of lithium battery pole pieces, but direct slicing, which reduces the process flow and system complexity, thereby improving reliability and reducing costs.

The process of preparing the pole piece using the pole piece preparation system of the present embodiment is described as follows:

S1. Put the pole belt into the unwinding device 1;

S2, the pole belt passes through the double-sided coating module 22 and the suspension oven 23 in the first coating and drying device 2, and the double-sided coating module 32 and the suspension oven 33 in the second coating and drying device 3 , the double-sided coating module 42 and the suspension oven 43 in the third coating and drying device 4 form three layers of coating layers;

S3, the pole strip that has formed three layers of paint layers enters the rolling device 5 for rolling;

S4. The pole strip after being rolled enters the sheet making device 6 to be made into a pole piece and collected;

Among them, in the process of passing through each coating and drying device in step S2 and in step S3, the tension control deviation correction module and the rolling tension belt guide module are used to control the tension and position of the pole belt. After the pole belt enters the film making device 6 and before it is made into a pole piece, the tension control and deviation correction are carried out through the tension control and deviation correction module, so as to realize the tension and position controllable transmission of the pole belt.

Embodiment 2 of pole piece preparation system

Referring to Fig. 6, in this embodiment two, the difference from the above-mentioned embodiment one is that the rolling device 5 is arranged on the feed side of the last coating drying device (the third coating drying device 4) and The sheet making device 6 is arranged on the discharge side of the last coating and drying device (the third coating and drying device 4 ).

The process of preparing the pole piece using the pole piece preparation system of the present embodiment is described as follows:

S1. Put the pole belt into the unwinding device 1;

S2, the pole belt passes through the double-sided coating module 22 and the suspension oven 23 in the first coating and drying device 2, and the double-sided coating module 32 and the suspension oven 33 in the second coating and drying device 3 , forming two coating layers;

S3, the pole strip that has formed two layers of paint layers enters the rolling device 5 for rolling;

S4, the pole strip after rolling passes through the double-sided coating module 42 and the suspension oven 43 in the third coating and drying device 4 to form a third coating layer;

S5. The pole strip after being rolled enters the sheet making device 6 to be made into a pole piece and collected;

Among them, in the process of passing through each coating and drying device in step S2 and step S4 and in step S3, the tension control deviation correction module and the roller pressure tension belt module are used to control the tension and position of the pole belt. After the pole belt enters the film making device 6 and before it is made into a pole piece, the tension control and deviation correction module is used to control the tension and correct the deviation of the pole belt, so as to realize the tension and position controllable transmission of the pole belt.

Combining the first and second embodiments above, after three-layer coating, a pole piece with higher performance can be obtained, which provides sufficient options for process design. In addition, the number of coatings can be selected according to process requirements. If it is necessary to reduce or increase the number of coatings, the number of coating and drying devices can be reduced or increased accordingly. And, according to the thickness of the coating and the properties of the coating, the number of suspension ovens in the coating drying device can be increased or decreased accordingly. In addition, according to process requirements, the arrangement sequence of Embodiment 1 or Embodiment 2 can be selected.

Preferably, the modules with the same function are composed of the same parts, try to simplify and reduce the parts, thereby reducing the complexity of the equipment, improving the reliability of the equipment, while improving production efficiency and reducing energy consumption. The fully automated and streamlined scale manufacturing of the production line creates the foundation.

The pole piece preparation system of the present invention cancels the winding mechanism used in the prior art. On the one hand, it eliminates the influence of the pole piece warpage caused by the curling caused by winding on the performance of the lithium-ion battery. On the other hand, it reduces the The process reduces manual operations, which is conducive to improving product consistency, improving production efficiency, and reducing production costs.

In particular, the roller-type tension guide belt module of the present invention enables modular series connection to be realized. Furthermore, the pole piece preparation system adopts a modular design. The entire line adopts a centralized control system for coordinated control, and each module adopts a sub-level control system.

An embodiment of the coating and drying method for pole strips

An embodiment of the coating and drying method for the pole belt of the present invention includes the following steps: the pole belt is conveyed under tension control, and during the transmission process, the slurry is firstly coated on both sides of the pole belt at the same time , and then dry both sides of the pole belt simultaneously in a suspension oven. Wherein, the tension control of the pole belt and the wind force in the suspension oven jointly control the suspension of the pole belt through the suspension oven.

With this coating and drying method, both sides of the pole strip can be coated at the same time, and the pole strip can be suspended through one step through the combination of the tension control of the pole strip and the wind force in the suspension oven to control the pole strip. Suspension oven, so as to realize the drying of both sides of the pole belt at the same time. Thus, both sides of the pole strip are coated and dried at the same time, which improves the efficiency of the production process. The simultaneous coating of the front and back sides can improve the performance consistency of the fabricated pole piece.

In this embodiment, the coating and drying device in the above pole piece preparation system can be used to implement the coating and drying method. Specifically, the tension control of the tension control and correction module and the traction force of the roller tension belt guide module on the pole belt are used to realize the controllable transmission of the tension of the pole belt.

Further, before the pole strip is coated, the pole strip is corrected by using a tension control deviation correction module. In this embodiment, the deviation correction mechanism in the tension control deviation correction module is used to perform this operation. Thus, the tension control deviation correction module and the roller tension belt guide module jointly carry out tension and position controllable transmission of the pole belt.

Further, coating may be gravure coating, spray coating or extrusion coating.

An embodiment of the pole piece preparation method

An embodiment of the pole piece preparation method of the present invention can apply the above pole piece preparation system shown in FIG. 1 . Specifically, the following steps are executed in sequence:

unwinding step;

Coating and drying step, using the above-mentioned coating and drying method for the pole strip to coat and dry the pole strip;

Rolling step, the tension and position controllable transmission of the dried pole belt is carried out, and the pole belt is rolled during the transmission process;

In the sheet-making step, the tension and position of the rolled pole strips are conveyed in a controlled manner, and then the pole strips are cut to make pole pieces, and finally the finished pole pieces are collected;

Wherein, the coating and drying step is performed at least once.

Another embodiment of the pole piece preparation method

Another embodiment of the pole piece preparation method of the present invention can be applied to the above pole piece preparation system shown in FIG. 6 . Specifically, the following steps are executed in sequence:

unwinding step;

Coating and drying step, using the above-mentioned coating and drying method for the pole strip to coat and dry the pole strip;

In the rolling step, the tension and position controllable transmission of the dried pole belt is carried out, and the pole belt is corrected and rolled during the transmission process;

In the coating and drying step, the above-mentioned coating and drying method for the pole strip is used to coat and dry the rolled pole strip again;

In the step of making sheets, the tension and position of the dried pole strips are conveyed in a controlled manner, and then the pole strips are cut to make pole pieces, and finally the pole pieces are collected;

Wherein, the coating and drying step performed before the rolling step is performed at least once.

Both of the above two pole piece preparation methods adopt the above coating and drying method to coat and dry the pole strip, which improves the efficiency of the production process. In addition, the way of coating the front and back (both sides) of the pole strip at the same time can improve the consistency of the performance of the pole piece made from the pole strip.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (11)

1. a coating and drying method for pole band, is characterized in that, comprises the steps: The tension belt is conveyed under controllable tension, and during the transmission process, the slurry is coated on both sides of the pole belt at the same time, and then the two sides of the pole belt are simultaneously dried in the suspension oven; Wherein, the tension control of the pole belt and the wind force in the suspension oven jointly control the suspension of the pole belt through the suspension oven. 2. the coating and drying method for pole band according to claim 1, characterized in that, The pole strip is deflected before it is coated. 3. the coating and drying method for pole band according to claim 1, characterized in that, The coating can be gravure coating, spray coating or extrusion coating. 4. A pole piece preparation method, is characterized in that, comprises the following steps of carrying out successively: unwinding step; Coating and drying step, adopting the coating and drying method for the pole strip described in any one of claims 1-3 to coat and dry the pole strip; Rolling step, the tension and position controllable transmission of the dried pole belt is carried out, and the pole belt is rolled during the transmission process; In the sheet-making step, the tension and position of the rolled pole strips are conveyed in a controlled manner, and then the pole strips are cut to make pole pieces, and finally the finished pole pieces are collected; Wherein, the coating and drying step is performed at least once. 5. A pole piece preparation method, is characterized in that, comprises the following steps of carrying out successively: unwinding step; Coating and drying step, adopting the coating and drying method for the pole strip described in any one of claims 1-3 to coat and dry the pole strip; Rolling step, the tension and position controllable transmission of the dried pole belt is carried out, and the pole belt is rolled during the transmission process; Coating and drying step, adopting the coating and drying method for the pole strip described in any one of claims 1-3 to coat and dry the pole strip after rolling again; In the step of making sheets, the tension and position of the dried pole strips are conveyed in a controlled manner, and then the pole strips are cut to make pole pieces, and finally the pole pieces are collected; Wherein, the coating and drying step performed before the rolling step is performed at least once. 6. A pole piece preparation system, characterized in that it comprises at least one set of coating and drying devices, the coating and drying devices comprising: Tension control deviation correction module for deviation correction and tension control of the pole belt, double-sided coating module for simultaneous coating of slurry on both sides of the pole belt, and double-sided coating module for the pole belt At least one suspension oven for simultaneous drying, and a roller-type tension belt guide module for providing traction to the pole belt; Wherein, the tension control deviation correction module, the double-sided coating module, the suspension oven and the roller tension belt guide module are arranged in sequence, the tension control deviation correction module, the roller press The type tension belt module and the suspension oven jointly control the suspension of the pole belt through the suspension oven. 7. The pole piece preparation system according to claim 6, further comprising: An unwinding device arranged on the feeding side of the coating and drying device, the unwinding device includes an inflatable shaft, an active unwinding servo mechanism, a tension detection device, and a deviation correction mechanism. 8. The pole piece preparation system according to claim 6, further comprising: a rolling device for rolling the pole strip and a sheet-making device for making the pole strip into a pole piece; When one coating and drying device is provided, the rolling device and the sheet-making device are sequentially arranged on the discharge side of the coating and drying device; When multiple coating and drying devices are provided, the rolling device and the sheet-making device are sequentially arranged on the discharge side of the last coating and drying device, or the rolling device is arranged on the last coating and drying device. The feeding side of the drying device and the tablet making device are arranged on the discharging side of the coating drying device. 9. The pole piece preparation system according to claim 8, characterized in that, The rolling device includes a tension control deviation correction module, a rolling module, and a rolling tension belt module arranged in sequence; The film making device includes a tension control deviation correction module, a slicing module, and a film receiving module arranged in sequence. 10. The pole piece preparation system according to claim 6 or 9, characterized in that, The tension control and deviation correction module includes a tension control mechanism, a pole belt buffer adjustment mechanism, and a deviation correction actuator. 11. The pole piece preparation system according to claim 6 or 9, characterized in that, The rolling tension belt module includes a pair of pressure rollers, a bearing housing, a gear set and a servo driver; Wherein, both ends of the pressure roller are rotatably supported on the bearing seat, the servo driver drives the gear set to move, and the gear set drives the pair of pressure rollers to rotate synchronously.