Flexible film coating equipment

Abstract

The utility model relates to the technical field of solar cells, and particularly discloses flexible film coating equipment. The flexible film layer coating equipment comprises an unwinding unit, a coating unit, a solvent removing unit, an annealing unit and a winding unit, a driving conveying mechanism is distributed between the unwinding unit and the winding unit, drives the continuous flexible base material to move from the unwinding unit to the winding unit, and sequentially passes through the coating unit, the solvent removing unit and the annealing unit; wherein the solvent removing unit and the annealing unit are independently arranged. The coating equipment is reasonable in procedure arrangement, the solvent removal unit and the annealing unit are independently arranged, the drying mode of existing coating equipment is improved, uneven perovskite crystallization caused by the temperature influence during solvent removal is avoided, and preparation of a high-quality perovskite layer is effectively guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and specifically discloses a flexible film layer coating device. Background Art

[0002] This section is used to elaborate on the content related to the present application, which is not necessarily the publicly available prior art.

[0003] In recent years, flexible perovskite solar cells have developed rapidly. With the continuous progress of technology, their photovoltaic efficiency has reached 23.6%, showing great potential.

[0004] However, in the process of preparing flexible perovskite solar cells, using a conventional flexible material coating device directly will cause many problems. For example: 1. The solvent removal process and the drying and annealing process of the conventional coating device are carried out simultaneously. When removing the solvent, it will be affected by the temperature of the drying and annealing process, resulting in uneven crystallization of perovskite, and thus it is impossible to ensure obtaining a high-quality perovskite layer; 2. When the conventional coating device is winding up, the front and back sides of the coated flexible substrate are wound and contacted, and it will be subjected to a large winding extrusion, which is easy to damage the perovskite layer prepared on it; 3. The conventional coating device generally realizes the tension isolation of the flexible substrate through the contact pressing of the metal roller and the rubber roller, which is also easy to damage the perovskite layer prepared on it. Summary of the Utility Model

[0005] The purpose of the present application is to solve at least some of the technical problems proposed in the above content, and this purpose is achieved through the following technical solutions:

[0006] The present application proposes a flexible film layer coating device, which includes an unwinding unit, a coating unit, a solvent removal unit, an annealing unit and a winding unit; a driving transmission mechanism is distributed between the unwinding unit and the winding unit, and the driving transmission mechanism drives a continuous flexible substrate to displace from the unwinding unit to the winding unit, and sequentially passes through the coating unit, the solvent removal unit and the annealing unit; wherein, the solvent removal unit and the annealing unit are independently arranged.

[0007] In some embodiments, the coating unit coats a coating solution on the front side of the flexible substrate, and the coating solution contains a coating solvent; the solvent removal unit includes an air knife mechanism, and the air knife mechanism blows air to volatilize the coating solvent; the annealing unit includes a heating plate, and the heating plate bakes and cures the coating solution to form a film layer.

[0008] In some embodiments, when the driving transmission mechanism drives the flexible substrate to displace, the driving transmission mechanism does not contact the film layer coated on the coating surface of the flexible substrate.

[0009] In some embodiments, the winding unit includes a rotatably arranged winding core and an auxiliary core; a continuous separating structure is wound around the auxiliary core, and the winding core synchronously winds the separating structure and the flexible substrate; the separating structure is located between adjacent two layers of the flexible substrate and forms an isolation gap between the adjacent two layers of the flexible substrate.

[0010] In some embodiments, if the isolation gap is H, then 0.2 mm ≤ H ≤ 2 mm.

[0011] In some embodiments, the separating structure includes a gasket and two first cushion strips arranged on both sides in its width direction, and the two first cushion strips and the gasket form a receiving cavity; the flexible substrate is located in the receiving cavity, and the back surface of the flexible substrate is attached to the gasket.

[0012] In some embodiments, the separating structure includes two second cushion strips arranged at intervals, and the two second cushion strips are attached to both sides of the flexible substrate in the width direction, and the two second cushion strips and the adjacent two layers of the flexible substrate form a sealing channel; a blowing port is formed on the circumferential surface of the winding core, and the blowing port blows air to fill the sealing channel.

[0013] In some embodiments, the driving and conveying mechanism includes a vacuum adsorption roller, and the vacuum adsorption roller is arranged at least upstream and downstream of the annealing unit, and the vacuum adsorption roller adsorbs the back surface of the flexible substrate; the driving and conveying mechanism further includes a first traction roller, a second traction roller, a coating back roller, a supporting conveyor belt and a metal guide roller; the first traction roller is arranged between the unwinding unit and the coating unit, and the second traction roller is arranged between the annealing unit and the unwinding unit; the coating back roller, the supporting conveyor belt and the metal guide roller are respectively arranged at the positions corresponding to the coating unit, the solvent removing unit and the annealing unit.

[0014] In some embodiments, the flexible film layer coating equipment further includes an electrostatic dust removal mechanism, and the electrostatic dust removal mechanism is arranged between the unwinding unit and the coating unit, and the electrostatic dust removal mechanism is used for neutralizing the static electricity on the front surface of the flexible substrate and removing dust.

[0015] In some embodiments, the coating unit includes a slit coating mechanism, a gravure coating mechanism, a microgravure reverse coating mechanism or a doctor blade coating mechanism; the coating unit includes a wind shield and a double air knife structure, and the wind shield and the double air knife structure are arranged front and back along the displacement direction of the flexible substrate; the annealing unit includes a preheating oven, a solid baking oven and a cooling oven arranged in sequence, a preheating heating plate is arranged in the preheating oven, a solid baking heating plate is arranged in the solid baking oven, and a cooling air nozzle is arranged in the cooling oven.

[0016] The flexible film layer coating equipment provided by the present application at least has the following technical effects:

[0017] In the present application, the driving and conveying mechanism drives the continuous flexible substrate to displace from the unwinding unit to the winding unit, and sequentially passes through the coating unit, the solvent removing unit and the annealing unit; wherein, the solvent removing unit and the annealing unit are independently arranged.

[0018] The coating equipment process layout of this application is reasonable. Except that the solvent removal unit and the annealing unit are independently arranged, the drying method of the existing coating equipment is improved, avoiding uneven crystallization of perovskite due to the influence of temperature during solvent removal, and effectively ensuring the preparation of a high-quality perovskite layer. Brief Description of the Drawings

[0019] In order to better combine the content shown in the drawings of the specification with the content described in the specific implementation manners, the drawings of the specification are briefly introduced below. It can be understood that the drawings of the specification mentioned below only schematically show some embodiments of the related technical solutions and the solutions of this application. Without creative efforts, those skilled in the art can also draw drawings showing other embodiments.

[0020] Specifically, the annotations for the drawings of the specification are as follows:

[0021] Figure 1 It is a schematic structural diagram of the flexible film layer coating equipment according to the embodiment of this application;

[0022] Figure 2 It is a structural diagram of the first winding method according to the embodiment of this application;

[0023] Figure 3 It is a cross-sectional view of the first winding method according to the embodiment of this application;

[0024] Figure 4 It is a structural diagram of the second winding method according to the embodiment of this application;

[0025] Figure 5 It is a cross-sectional view of the second winding method according to the embodiment of this application.

[0026] Specifically, the annotations for the reference numerals in the drawings of the specification are as follows:

[0027] 100, flexible film layer coating equipment; 110, unwinding unit; 111, unwinding core; 120, winding unit; 121, winding core; 1211, air blowing port; 122, auxiliary core; 130, coating unit; 131, slot coating mechanism; 140, solvent removal unit; 141, wind baffle; 142, double air knife structure; 150, annealing unit; 151, preheating oven; 152, solid baking oven; 153, cooling oven; 154, preheating heating plate; 155, solid baking heating plate; 156, cooling air nozzle; A, driving transmission mechanism; a1, vacuum adsorption roller; a2, first traction roller; a3, second traction roller; a4, coating back roller; a5, supporting conveyor belt; a6, metal guide roller; B, electrostatic dust removal mechanism; C, flexible substrate; D, separation structure; d1, gasket; d2, first cushion strip; d3, second cushion strip. Detailed implementation manners

[0028] To make the content of the embodiments of this application clearer, the following will be described in conjunction with the accompanying drawings of the specification. It can be understood that the content mentioned below is only a part of the embodiments in this application, rather than all the embodiments. Based on this, without creative work, other embodiments obtained by those skilled in the art fall within the scope of protection of this application.

[0029] It should be understood that the terms used in this document are only for the purpose of describing specific embodiments and are not intended to be restrictive. Unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" as used in this document may also include the plural forms. The terms "comprising", "including", and "having" are inclusive and thus specify the presence of the stated features, elements, and / or components, but do not preclude the presence or addition of one or more other features, elements, components, and / or combinations thereof.

[0030] Although terms such as first and second can be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms can only be used to distinguish one element, component, region, layer, or segment from another region, layer, or segment. Unless the context clearly indicates otherwise, terms such as "first" and "second" and other numerical terms do not imply an order or sequence when used in this document. In addition, in the description of this application, unless otherwise clearly specified and limited, the terms "arranged", "connected", and "installed" 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 directly connected, or indirectly connected through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0031] For the convenience of description, spatial relative relationship terms can be used in this document to describe the relationship of one element or feature relative to another element or feature. These relative relationship terms are, for example, "inner", "outer", "end", "side", "middle", "upper", "lower", "high", "low", "axial", "circumferential", "radial", "horizontal", "vertical", "first direction", "second direction", etc. Such spatial relative relationship terms are intended to include different orientations of the mechanism in use or operation other than the orientations shown in the figures.

[0032] The following mainly elaborates on the embodiments of this application in conjunction with the accompanying drawings of the specification.

[0033] Refer to Figure 1, this application proposes a flexible film layer coating device 100, which includes an unwinding unit 110, a coating unit 130, a solvent removal unit 140, an annealing unit 150 and a winding unit 120; a driving transmission mechanism A is distributed between the unwinding unit 110 and the winding unit 120, and the driving transmission mechanism A drives the continuous flexible substrate C to displace from the unwinding unit 110 to the winding unit 120, and sequentially passes through the coating unit 130, the solvent removal unit 140 and the annealing unit 150; wherein, the solvent removal unit 140 and the annealing unit 150 are independently arranged.

[0034] In this embodiment, the process layout of the coating device is reasonable, the solvent removal unit 140 and the annealing unit 150 are independently arranged, which improves the drying method of the existing coating device, avoids uneven crystallization of perovskite caused by the influence of temperature during solvent removal, and effectively ensures the preparation of a high-quality perovskite layer.

[0035] In some embodiments, the coating unit 130 coats the front side of the flexible substrate C with a coating solution, and the coating solution contains a coating solvent; further, in some embodiments, the coating unit 130 includes any one or any combination of two or more of a slot coating mechanism 131, a gravure coating mechanism, a microgravure reverse coating mechanism and a doctor blade coating mechanism to ensure uniform coating.

[0036] It should be noted that the coating solution mentioned in this application can be a perovskite precursor solution or a precursor solution of other flexible batteries, and will not be exemplified one by one here.

[0037] In some embodiments, referring to Figure 1 , the solvent removal unit 140 includes an air knife mechanism, and the air knife mechanism blows air to volatilize the coating solvent; further, in some embodiments, the coating unit 130 includes a wind shield 141 and a double air knife structure 142, and the wind shield 141 and the double air knife structure 142 are arranged front and back along the displacement direction of the flexible substrate C.

[0038] In the above embodiment, the wind shield 141 plays a role in controlling the air flow. It can prevent the external air flow from interfering with the coating area and maintain the stability of the coating environment. In addition, the wind shield 141 can also help adjust the temperature distribution to ensure that the wet film after coating is heated evenly during the drying process and avoid film layer quality problems caused by uneven temperature. In addition, the double air knife structure 142 accelerates the evaporation of the coating solvent by blowing air, thereby accelerating the drying speed and improving production efficiency. At the same time, the double air knife can also help form a uniform film layer and avoid unevenness or crusting on the surface of the film layer.

[0039] In some embodiments, the annealing unit 150 includes a heating plate, and the heating plate bakes and cures the coating solution to form a film layer. Further, in some embodiments, referring to Figure 1, the annealing unit 150 includes a preheating oven 151, a solid baking oven 152, and a cooling oven 153 arranged in sequence. A preheating heating plate 154 is provided in the preheating oven 151, a solid baking heating plate 155 is provided in the solid baking oven 152, and a cooling air nozzle 156 is provided in the cooling oven 153.

[0040] In the above embodiment, preheating is a process of gradually heating the coated flexible substrate C to a certain temperature. The purpose is to soften or melt the solvent or binder in the coating material to prepare for the subsequent curing process. Preheating helps reduce thermal shock and avoid internal stress in the material caused by too rapid temperature change. Solid baking, also known as curing, is a process in which the binder or polymer in the coating material undergoes a chemical reaction at a certain temperature to form a stable three-dimensional network structure. The curing process ensures the mechanical strength and chemical stability of the coating layer, which is crucial for the performance of the battery; curing can also improve the conductivity of the electrode material and the overall charge-discharge performance of the battery. Cooling is a process of gradually cooling the cured coating material to room temperature to ensure the structural stability of the coating layer; the cooling process helps release the internal stress that may be generated during the curing process and prevent the material from cracking or deforming; cooling can also make the physical and chemical properties of the coating layer reach the best state, providing guarantee for the subsequent processing and use of the battery.

[0041] In some embodiments, when the driving transmission mechanism A drives the flexible substrate C to displace, the driving transmission mechanism A does not contact the film layer on the flexible substrate C. Further, in some embodiments, referring to Figure 1 , the driving transmission mechanism A includes a vacuum adsorption roller a1. The vacuum adsorption roller a1 is provided at least upstream and downstream of the annealing unit 150. The vacuum adsorption roller a1 adsorbs the back surface of the flexible substrate C; the driving transmission mechanism A further includes a first traction roller a2, a second traction roller a3, a coating back roller a4, a support conveyor belt a5, and a metal guide roller a6; the first traction roller a2 is provided between the unwinding unit 110 and the coating unit 130, and the second traction roller a3 is provided between the annealing unit 150 and the unwinding unit 110; the coating back roller a4, the support conveyor belt a5, and the metal guide roller a6 are respectively provided at the positions of the coating unit 130, the solvent removal unit 140, and the annealing unit 150.

[0042] In the above embodiment, the driving transmission mechanism A realizes the purpose of driving the flexible substrate C to displace through the mutual cooperation of each specific component, and each transmission component only contacts the back surface of the flexible substrate C and does not contact the film layer, avoiding damaging the film layer. As Figure 1As shown, through the design of the relative positions of the components of the driving and conveying mechanism A, during the conveying process, all components of the driving and conveying mechanism A are located on the back side of the flexible substrate C, so that the driving and conveying mechanism A only contacts the back of the flexible substrate C and does not contact the film layer deposited on the flexible substrate C, which can avoid the contamination or damage of the film layer deposited on the flexible substrate C by the driving and conveying mechanism A. In addition, the vacuum adsorption roller a1 provides the function of tension isolation, avoiding wrinkles or slack of the material, thus maintaining the flatness of the material, and can control the running speed of the flexible substrate C to ensure the uniformity and consistency of coating.

[0043] In some embodiments, referring to Figure 1 , the winding unit 120 includes a rotatably arranged winding core 121 and an auxiliary core 122; the auxiliary core 122 is wound with a continuous separating structure D, and the winding core 121 synchronously winds the separating structure D and the flexible substrate C; the separating structure D is located between adjacent two layers of the flexible substrate C and forms an isolation gap between adjacent two layers of the flexible substrate C. Further, in some embodiments, if the isolation gap is H, then 0.2 mm ≤ H ≤ 2 mm.

[0044] In the above embodiments, the isolation gap refers to the non-contact and gap between the film layer coated on the flexible substrate C and the adjacent layer of the wound flexible substrate C, so as to avoid contamination or damage to the film layer. Among them, the isolation gap should not be too large or too small; if the isolation gap is too small, there is a risk of easily touching and squeezing the film layer during winding, resulting in the failure of isolation; if the isolation gap is too large, the winding is inconvenient and the volume after winding is too large, which is not conducive to subsequent production. In practice, the more appropriate range of the isolation gap is 0.2 mm to 2 mm. For example, the isolation gap can be but not limited to 0.2 mm, 0.6 mm, 1 mm, 1.5 mm, and 2 mm.

[0045] To more clearly elaborate on the above solution, two embodiments of the separating structure D are presented below:

[0046] In one of the embodiments, referring to Figure 2 and Figure 3 , the separating structure D includes a gasket d1 and two first cushion strips d2 provided on both sides in its width direction, and the two first cushion strips d2 and the gasket d1 form a receiving cavity; the flexible substrate C is located in the receiving cavity, and the back of the flexible substrate C is attached to the gasket d1.

[0047] In another embodiment, referring to Figure 4 and Figure 5, the separation structure D includes two second cushion strips d3 arranged at intervals. The two second cushion strips d3 are attached to both sides of the flexible substrate C in the width direction. The two second cushion strips d3 and the adjacent two layers of flexible substrate C form a sealed channel. The circumferential surface of the winding core 121 is provided with a blowing port 1211, and the blowing port 1211 blows air to fill the sealed channel. The presence of the second cushion strip d3 can play a blocking role between two adjacent layers of flexible substrate C. By blowing air through the blowing port 1211, it can further promote the separation of two adjacent layers of flexible substrate C, and at the same time, it can also promote or maintain the drying of the flexible substrate C and the film layer thereon.

[0048] It can be understood that the separation structure D can also be other embodiments, as long as it can achieve the purpose of isolating the gap, it belongs to the protection scope of the present application.

[0049] In addition, in some embodiments, the unwinding unit 110 includes an unwinding core 111 rotatably arranged, and an unprocessed flexible substrate C is wound on the unwinding core 111.

[0050] In some embodiments, referring to Figure 1 , the flexible film coating device further includes an electrostatic dust removal mechanism B. The electrostatic dust removal mechanism B is arranged between the unwinding unit 110 and the coating unit 130, and the electrostatic dust removal mechanism B is used to neutralize the static electricity on the front side of the flexible substrate C and remove dust.

[0051] In the coating process, due to the friction of materials, static electricity may be generated, which will affect the coating uniformity and quality. The electrostatic dust removal mechanism B can remove static electricity by neutralizing charges; moreover, the coating environment needs to be kept clean to avoid dust and other particles from contaminating the coating materials. The electrostatic dust removal mechanism B can effectively remove the particulate matter on the flexible substrate C and in the air, ensuring the cleanliness of the coating environment. By removing static electricity and purifying the air, the electrostatic dust removal mechanism B helps to improve the uniformity and adhesion of the coating layer, thereby improving the overall quality of the battery film layer. In addition, static electricity may cause uneven adsorption of materials, resulting in material waste. Therefore, the electrostatic dust removal mechanism B helps to reduce material waste by reducing the influence of static electricity.

[0052] In particular, the term "and / or" in the present application should be understood as follows:

[0053] First, the term "and / or" located between the first main body and the second main body includes any of the following meanings: (1) only the first main body; (2) only the second main body; and (3) the first main body and the second main body.

[0054] Secondly, the term "and / or" between the last two of three or more entities refers to including at least any one of the multiple entities. For example, "the first entity, the second entity, and / or the third entity" has the same meaning as "the first entity and / or the second entity and / or the third entity", and specifically includes the following combinations: (1) only the first entity; (2) only the second entity; (3) only the third entity; (4) the first entity and the second entity without the third entity; (5) the first entity and the third entity without the second entity; (6) the second entity and the third entity without the first entity; and (7) the first entity, the second entity, and the third entity.

[0055] In addition, although the above has described embodiments of the present application in conjunction with the accompanying drawings, those skilled in the art can also make various modifications and variations without departing from the concept of the present application, and such modifications and variations shall fall within the scope defined by the appended claims.

Claims

1. A flexible film coating device, characterized in that: It comprises an unwinding unit (110), a coating unit (130), a solvent removal unit (140), an annealing unit (150) and a winding unit (120); A driving transmission mechanism (A) is arranged between the unwinding unit (110) and the rewinding unit (120), and the driving transmission mechanism (A) drives the continuous flexible substrate (C) to move from the unwinding unit (110) to the rewinding unit (120), and sequentially passes through the coating unit (130), the solvent removal unit (140), and the annealing unit (150); Wherein, the solvent removal unit (140) and the annealing unit (150) are arranged independently of each other.

2. The flexible film coating device according to claim 1, characterized in that: The coating unit (130) coats the front surface of the flexible substrate (C) with a coating liquid, wherein the coating liquid contains a coating solvent; The solvent removal unit (140) comprises an air knife mechanism, and the air knife mechanism blows air to volatilize the coating solvent; The annealing unit (150) comprises a heating plate, and the heating plate bakes and solidifies the coating solution to form a film layer.

3. The flexible film coating device according to claim 1, characterized in that: When the driving transmission mechanism (A) drives the flexible substrate (C) to move, the driving transmission mechanism (A) does not contact the film layer coated on the coating surface of the flexible substrate (C).

4. The flexible film coating device according to claim 1, characterized in that: The winding unit (120) comprises a rotatably arranged winding tube core (121) and an auxiliary tube core (122); The auxiliary tube core (122) is wound with a continuous partition structure (D), and the winding tube core (121) synchronously winds up the partition structure (D) and the flexible substrate (C); The separation structure (D) is located between two adjacent layers of the flexible substrate (C) and forms an isolation gap between the two adjacent layers of the flexible substrate (C).

5. The flexible film coating device according to claim 4, characterized in that: The isolation gap is H, then 0.2mm≤H≤2mm.

6. The flexible film coating device according to claim 4, characterized in that: The partition structure (D) comprises a gasket (d1) and two first gasket strips (d2) arranged on both sides of the gasket in a width direction, wherein the two first gasket strips (d2) and the gasket (d1) form a receiving cavity; The flexible substrate (C) is located in the accommodating cavity, and the back surface of the flexible substrate (C) is attached to the gasket (d1).

7. The flexible film coating device according to claim 4, characterized in that: The partition structure (D) comprises two second gasket strips (d3) arranged at intervals, the two second gasket strips (d3) are attached to both sides of the flexible substrate (C) in the width direction, and the two second gasket strips (d3) form a sealed channel with two adjacent layers of the flexible substrate (C); The circumferential surface of the winding tube core (121) is provided with an air blowing port (1211), and the air blowing port (1211) blows air to fill the sealing channel.

8. The flexible film coating device according to claim 1, characterized in that: The driving transmission mechanism (A) comprises a vacuum adsorption roller (a1), wherein the vacuum adsorption roller (a1) is at least arranged upstream and downstream of the annealing unit (150), and the vacuum adsorption roller (a1) adsorbs the back side of the flexible substrate (C); The driving transmission mechanism (A) also includes a first traction roller (a2), a second traction roller (a3), a coating back roller (a4), a supporting conveyor belt (a5) and a metal guide roller (a6); the first traction roller (a2) is arranged between the unwinding unit (110) and the coating unit (130), and the second traction roller (a3) ​​is arranged between the annealing unit (150) and the unwinding unit (110); the coating back roller (a4), the supporting conveyor belt (a5) and the metal guide roller (a6) are respectively arranged at the positions of the coating unit (130), the solvent removal unit (140) and the annealing unit (150).

9. The flexible film coating device according to any one of claims 1 to 8, characterized in that: The flexible film coating device (100) further comprises an electrostatic dust removal mechanism (B), wherein the electrostatic dust removal mechanism (B) is arranged between the unwinding unit (110) and the coating unit (130), and the electrostatic dust removal mechanism (B) is used to neutralize static electricity on the front side of the flexible substrate (C) and remove dust.

10. The flexible film coating device according to any one of claims 1 to 8, characterized in that: The coating unit (130) comprises a slit coating mechanism (131), a gravure printing coating mechanism, a micro-concave reverse coating mechanism or a blade coating mechanism; The coating unit (130) comprises a windshield (141) and a double wind knife structure (142), wherein the windshield (141) and the double wind knife structure (142) are arranged front and back along the displacement direction of the flexible substrate (C); The annealing unit (150) comprises a preheating oven (151), a solid baking oven (152) and a cooling oven (153) which are arranged in sequence, the preheating oven (151) is provided with a preheating heating plate (154), the solid baking oven (152) is provided with a solid baking heating plate (155), and the cooling oven (153) is provided with a cooling air nozzle (156).

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