Electrochromic diaphragm and electrochromic device

Abstract

The embodiment of the present application relates to an electrochromic film and an electrochromic device. The electrochromic film comprises bus bars arranged on two opposite surfaces thereof and a packaging layer covering the bus bars, the packaging layer can form a packaging structure for sealing the bus bars after being at least partially melted, and the packaging layer is at least one of a non-polar material layer, a polyolefin layer, an epoxy system material layer, a POE layer and a PIB layer. In the present application, the packaging layer is arranged to reduce the risk of bus bar failure and device appearance defects.

Description

[0001] This application claims domestic priority to Chinese patent application No. 202511299267.X, filed with the Chinese Patent Office on September 10, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of electrochromic technology, and in particular to an electrochromic film and an electrochromic device. Background Technology

[0003] Flexible electrochromic films are flexible thin films that can change color. Under the influence of an external electric field, the color or light transmittance of the electrochromic film changes, allowing light beams to pass through completely, partially, or completely, thus exhibiting colored, intermediate, and transparent states. In recent years, electrochromic films have been increasingly used in various fields such as electronic devices, wearable devices, transportation vehicles, and construction. However, the busbars of existing electrochromic films are susceptible to corrosion and failure by water and oxygen, shortening the lifespan of the electrochromic film. Utility Model Content

[0004] This application provides an electrochromic film and an electrochromic device, aiming to solve the problem that the busbar of the electrochromic film is prone to failure.

[0005] In a first aspect, this application provides an electrochromic film, the electrochromic film comprising busbars disposed on its two opposite surfaces and an encapsulation layer covering the busbars, wherein the encapsulation layer, after at least partially melting, can form an encapsulation structure for sealing the busbars, and the encapsulation layer is at least one of a non-polar material layer, a polyolefin layer, an epoxy system material layer, a POE layer, and a PIB layer.

[0006] In this embodiment, the busbars are covered by encapsulation layers, which initially encapsulates the busbars and reduces the risk of the electrochromic diaphragm failing due to corrosion from water and oxygen during short-term storage and transportation. In subsequent use, the encapsulation layers can be melted or partially melted through heat treatment. The melted encapsulation layer forms an encapsulation structure attached to at least a portion of the busbar surface, isolating at least a portion of the busbar from the external environment. This reduces the risk of the electrochromic diaphragm failing due to corrosion from water and oxygen during use, and also reduces the risk of ion leaching from the electrochromic layer corroding the busbar, thus improving the service life of the electrochromic diaphragm.

[0007] In one embodiment, the resistivity of the encapsulation layer is greater than the resistivity of the PVB; and / or

[0008] The ion migration rate of the encapsulation layer is less than that of the PVB; and / or

[0009] The thickness of the encapsulation layer is greater than or equal to the thickness of the electrochromic film; and / or

[0010] The resistivity of the encapsulation layer is greater than 10. 16 Ω·cm; and / or

[0011] The yellowing index ΔYI of the encapsulation layer is less than or equal to 3.

[0012] In one embodiment, one end of the encapsulation layer extends beyond the edge of the electrochromic film, and the encapsulation layer can cover the periphery of the electrochromic film after being heat-melted.

[0013] In one embodiment, the surface of the busbar is further covered with a waterproof layer, and the encapsulation layer covers the waterproof layer.

[0014] In one embodiment, the encapsulation layer is adhesive at room temperature and adheres to the surface of the waterproof layer.

[0015] Secondly, this application provides an electrochromic device, which includes a first substrate, an electrochromic film, a second substrate, and an adhesive layer disposed between the first substrate and the electrochromic film and between the second substrate and the electrochromic film. The busbars on opposite surfaces of the electrochromic film are covered with an encapsulation structure, which is at least one of a non-polar material layer, a polyolefin layer, an epoxy system material layer, a POE layer, and a PIB layer. The material of the encapsulation structure is different from the material of the adhesive layer.

[0016] In one embodiment, the material of the adhesive layer is selected from at least one of POE and PVB.

[0017] In one embodiment, the resistivity of the encapsulation structure is greater than the resistivity of the adhesive layer or the PVB material.

[0018] In one embodiment, the ion migration rate of the encapsulation structure is less than the ion migration rate of the adhesive layer or the PVB material; and / or

[0019] The thickness of the encapsulation structure is greater than or equal to the thickness of the electrochromic film; and / or

[0020] The resistivity of the packaging structure is greater than 10. 16 Ω·cm; and / or

[0021] The yellowing index ΔYI of the encapsulation structure is less than or equal to 3. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a top view of the electrochromic film in an embodiment of this application;

[0024] Figure 2 Examples of embodiments in this application Figure 1 A schematic cross-sectional view of the electrochromic film along the AA direction is shown.

[0025] Figure 3 Examples of embodiments in this application Figure 1 A schematic cross-sectional view of the electrochromic film along the BB direction is shown.

[0026] Figure 4 Examples of embodiments in this application Figure 3 One of the schematic cross-sectional views of the electrochromic film after heat treatment;

[0027] Figure 5 This is a schematic diagram of the electrochromic device in the embodiments of this application;

[0028] Figure 6 This is an exploded view of the electrochromic device in the embodiments of this application;

[0029] Figure 7 This is a schematic flowchart illustrating the fabrication method of the electrochromic device in the embodiments of this application.

[0030] Explanation of reference numerals in the attached figures:

[0031] Electrochromic film 10; first substrate layer 111; second substrate layer 112; first conductive layer 121; second conductive layer 122; electrochromic layer 130; first busbar 141; second busbar 142; first groove 151; second groove 152; first encapsulation layer 210; second encapsulation layer 220; first encapsulation structure 211; second encapsulation structure 221; first gap G1; second gap G2; electrochromic device 1; first substrate 21; first adhesive layer 31; second adhesive layer 32; second substrate 22. Detailed Implementation

[0032] To facilitate understanding of the embodiments of this application, a more comprehensive description of the embodiments of this application will be provided below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the embodiments of this application. However, the embodiments of this application can be implemented in many different forms and are not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the embodiments of this application more thorough and complete.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which embodiments of this application belong. The terminology used herein in the description of embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments of this application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0034] In the description of the embodiments of this application, it should be understood that the terms "upper", "lower", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the method or positional relationship shown in the drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0035] It is understood that the terms "first," "second," etc., used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first substrate layer may be referred to as a second substrate layer, and similarly, a second substrate layer may be referred to as a first substrate layer. Both the first substrate layer and the second substrate layer are substrate layers, but they are not the same substrate layer.

[0036] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. In the description of this application, "several" means at least one, such as one, two, etc., unless otherwise explicitly specified.

[0037] Please see Figure 1 , Figure 2 and Figure 3This application provides an electrochromic film 10, which includes busbars disposed on its two opposing surfaces and an encapsulation layer covering the busbars. Specifically, the two opposing surfaces of the electrochromic film 10 are a first surface and a second surface, the busbars include a first busbar 141 and a second busbar 142, and the encapsulation layer includes a first encapsulation layer 210 and a second encapsulation layer 220. The electrochromic film 10 also includes a first substrate layer 111, a first conductive layer 121, an electrochromic layer 130, a second conductive layer 122, and a second substrate layer 112. The first substrate layer 111, the first conductive layer 121, the electrochromic layer 130, the second conductive layer 122, and the second substrate layer 112 are sequentially stacked. "Sequentially stacked" means stacked sequentially along the stacking direction, and adjacent surfaces of adjacent layers are in contact along the stacking direction.

[0038] The first substrate layer 111 and the second substrate layer 112 are "transparent substrates". The transparent substrates are made of optical grade transparent materials, specifically flexible substrate materials such as PET (Polyester Film), cyclic olefin copolymers or cellulose triacetate.

[0039] The first conductive layer 121 and the second conductive layer 122 are "transparent conductive layers". The materials of the transparent conductive layers can be indium-tin oxide (ITO), aluminum zinc oxide (AZO), fluorine-doped tin oxide (FTO), silver nanowires, graphene, carbon nanotubes, metal meshes or silver nanoparticles, etc.

[0040] Generally, the electrochromic layer 130 includes an electrochromic material layer, an electrolyte layer, and an ion storage layer stacked sequentially. In one embodiment, the electrochromic material layer, electrolyte layer, and ion storage layer are all solid. The electrochromic material layer includes an electrochromic material, and the ion storage layer includes an ion storage material for storing ions. The electrolyte layer, also known as an ion transfer layer, serves as an ion transfer channel.

[0041] like Figure 2 As shown, the first busbar 141 is disposed on the first surface of the electrochromic film 10 and is electrically connected to the first conductive layer 121, and the second busbar 142 is disposed on the second surface of the electrochromic film 10 and is electrically connected to the second conductive layer 122. The first surface and the second surface are arranged opposite to each other along the thickness direction of the electrochromic film 10.

[0042] The first conductive layer 121 is connected to one terminal (e.g., the positive terminal) of the power supply via the first busbar 141, and the second conductive layer 122 is connected to the other terminal (e.g., the negative terminal) of the power supply via the second busbar 142. A voltage supplied by the power supply is applied between the first conductive layer 121 and the second conductive layer 122 through the two busbars, thereby changing the transmittance of the electrochromic film 10. The voltage causes ions to move between the electrochromic material layer and the ion storage layer, and to intercalate / extract or deintercalate / intercalate between them, thereby changing the optical state of the electrochromic material in the electrochromic material layer, and thus changing the transmittance of the electrochromic film 10, allowing the electrochromic film 10 to be adjusted between a colored state, an intermediate state, and a transparent state.

[0043] However, the first busbar 141 and the second busbar 142 are susceptible to corrosion from water, oxygen, and other substances in the air. Furthermore, ion leakage from the electrochromic layer 130 can also corrode the first busbar 141 and the second busbar 142. Especially in high-temperature environments, the rate of corrosion of the first busbar 141 and the second busbar 142 is accelerated, which can easily lead to the failure of the first busbar 141 and the second busbar 142, resulting in short circuits and open circuits.

[0044] In this embodiment of the application, a first encapsulation layer 210 and a second encapsulation layer 220 are provided in the electrochromic film 10 (e.g., Figure 2 and 3 (As shown). The first encapsulation layer 210 covers the first busbar 141, and the second encapsulation layer 220 covers the second busbar 142. The first encapsulation layer 210 provides preliminary encapsulation for the first busbar 141, and the second encapsulation layer 220 provides preliminary encapsulation for the second busbar 142. This reduces the risk of the electrochromic film 10 failing due to corrosion from water, oxygen, chemical reagents, etc., during short-term storage and transportation. Simultaneously, the encapsulation layers also provide a certain degree of physical fixation for the busbars, improving the reliability of the electrical connection between the busbars and conductive layers, etc.

[0045] Please see Figure 4 The encapsulation layers are configured to form an encapsulation structure for sealing the busbar after at least partial melting. Specifically, the first encapsulation layer 210 can form a first encapsulation structure 211 for sealing the first busbar 141 after at least partial melting. The second encapsulation layer 220 can form a second encapsulation structure 221 for sealing the second busbar 142 after at least partial melting.

[0046] Specifically, in one embodiment of this application, the entire first encapsulation layer 210 and the entire second encapsulation layer 220 have heat-melting adhesive properties. After heat treatment, they can cover the remaining surfaces of the busbar except for the surface connected to the conductive layer, thus providing an all-around seal for the busbar.

[0047] In other embodiments, both the first encapsulation layer 210 and the second encapsulation layer 220 are composed of hot-melt and non-hot-melt materials joined together, meaning that both the first encapsulation layer 210 and the second encapsulation layer 220 partially possess hot-melt adhesive properties. Covering the area requiring encapsulation with hot-melt material, which melts and encapsulates the specific area, can reduce costs.

[0048] When the electrochromic film 10 is applied, the first encapsulation layer 210 and the second encapsulation layer 220 can be completely melted or only partially melted by heat treatment. The molten first encapsulation layer 210 forms a first encapsulation structure 211 that adheres to the surface of the first busbar 141, and the molten second encapsulation layer 220 forms a second encapsulation structure 221 that adheres to the surface of the second busbar 142. This isolates the first busbar 141 and the second busbar 142 from the external environment, reducing the risk of the first busbar 141 and the second busbar 142 failing due to water and oxygen corrosion. It also reduces the risk of ion leaching corrosion of the first busbar 141 and the second busbar 142 in the electrochromic layer 130, which helps to improve the service life of the electrochromic film 10.

[0049] The heat treatment refers to heating the first encapsulation layer 210 and the second encapsulation layer 220 to a certain temperature to melt them. During the heat treatment process, a certain pressure can also be applied to ensure a tight fit between the encapsulation layer and the busbar in contact with it, thereby improving the encapsulation effect. Specifically, the entire electrochromic film 10 can be heat-treated, or only a portion or all of the first encapsulation layer 210 and the second encapsulation layer 220 can be heat-treated.

[0050] In one embodiment, the encapsulation layer is at least one of a non-polar material layer, a polyolefin layer, an epoxy system material layer, a POE layer, and a PIB layer. Specifically:

[0051] In one embodiment, the first encapsulation layer 210 is made of a non-polar material. The second encapsulation layer 220 is also made of a non-polar material. As an example, the non-polar material may be selected from at least one of POE, PIB (polyisobutylene), and epoxy resin.

[0052] In one embodiment, the materials of the first encapsulation layer 210 and the second encapsulation layer 220 include at least one of polyolefin materials and epoxy system materials. The polyolefin material may be selected from at least one of commercially available polyolefin elastomers (POE) and butyl rubber system materials. As an example, the butyl rubber system material may be PIB (polyisobutylene).

[0053] Wherein, POE is a fully saturated hydrocarbon chain. As an example, POE can be vinyl POE or propylene POE; vinyl POE can be an ethylene-octene copolymer, and propylene POE can be an propylene-octene copolymer.

[0054] Polyolefin materials (such as POE and PIB), epoxy materials, and butyl rubber materials all possess good isolation properties, especially POE and PIB materials, which exhibit excellent isolation performance. In this embodiment, the materials of the first encapsulation layer 210 and the second encapsulation layer 220 are defined to better isolate the first busbar 141 and the second busbar 142 from water and oxygen, reducing the risk of corrosion of the first busbar 141 and the second busbar 142. Furthermore, materials such as POE and PIB possess excellent mechanical stress buffering capabilities, reducing the risk of poor overlap between the busbar and the conductive layer due to stress, which helps to reduce the risk of busbar failure and improve the service life of the electrochromic film 10.

[0055] In one embodiment, the resistivity of the first encapsulation layer 210 is greater than 10. 16 Ω·cm. The resistivity of the second encapsulation layer 220 is greater than 10 Ω·cm. 16 Ω·cm. In this embodiment, the first encapsulation layer 210 and the second encapsulation layer 220 have high resistivity, which can significantly suppress ion migration behavior, giving the first encapsulation layer 210 and the second encapsulation layer 220 excellent encapsulation protection performance. This helps reduce the risk of ion oozing corrosion of the first busbar 141 and the second busbar 142 in the electrochromic layer 130, and improves the service life of the electrochromic film 10.

[0056] In one embodiment, the resistivity of the first encapsulation layer 210 and the second encapsulation layer 220 is greater than the resistivity of the PVB (polyvinyl butyral) material. The resistivity of PVB material is typically 10⁻⁶. 12 When the encapsulation layer material is POE, the resistivity of the encapsulation layer is at least four orders of magnitude higher than that of PVB. In this embodiment, the first encapsulation layer 210 and the second encapsulation layer 220 have a higher resistivity than PVB, which can significantly suppress ion migration behavior, giving the first encapsulation layer 210 and the second encapsulation layer 220 excellent encapsulation protection performance. This helps reduce the risk of ion oozing and corrosion of the first busbar 141 and the second busbar 142 in the electrochromic layer 130.

[0057] In one embodiment, the ion migration rates of the first encapsulation layer 210 and the second encapsulation layer 220 are lower than the ion migration rate of the PVB material. In this embodiment, the encapsulation layer has a lower ion migration rate, which can effectively suppress ion permeation from the electrochromic layer 130 and diffusion to the busbar, reducing the risk of busbar open circuit and failure.

[0058] In one embodiment, the yellowing index ΔYI of the first encapsulation layer 210 is less than or equal to 3. The yellowing index ΔYI of the second encapsulation layer 220 is less than or equal to 3. The yellowing index ΔYI (Delta Yellowness Index) is a quantitative indicator that measures the degree of yellowing change of a material during processing, storage, or use. It refers to the difference between the final YI value and the initial YI value after the material has undergone specific conditions (such as aging tests or storage periods). In this embodiment, the low yellowing index ΔYI values ​​of the first encapsulation layer 210 and the second encapsulation layer 220 make them less prone to yellowing during long-term use, especially under long-term exposure to light, high temperature, and high humidity, thus allowing the electrochromic film 10 to maintain a good appearance.

[0059] In one embodiment, the surface of the busbar is covered with waterproof tape, and an encapsulation layer is also covered with waterproof tape. This double seal of waterproof tape and encapsulation layer reduces the risk of corrosion.

[0060] Please see Figures 1 to 3 In one embodiment, the electrochromic film 10 further has a groove, and at least a portion of the busbars are electrically connected to a conductive layer exposed within the groove. Specifically, the edge region of the electrochromic film 10 is provided with a first groove 151 and a second groove 152. Along the thickness direction of the electrochromic film 10, the first groove 151 penetrates the second base layer 112, the second conductive layer 122, and the electrochromic layer 130, exposing the corresponding first conductive layer 121, and at least a portion of the first busbars 141 are electrically connected to the first conductive layer 121 within the first groove 151. Along the thickness direction of the electrochromic film 10, the second groove 152 penetrates the first base layer 111, the first conductive layer 121, and the electrochromic layer 130, exposing the second conductive layer 122, and at least a portion of the second busbars 142 are electrically connected to the second conductive layer 122 within the second groove 152.

[0061] In one embodiment, the number of first grooves 151 and second grooves 152 is multiple, such as... Figure 1 As shown, the projections of the first groove 151 and the second groove 152 on the plane of the diaphragm are alternately and intermittently arranged. Figure 1 The second groove 152 is indicated by a solid line, which means that it is seen from the first base layer 111 to the second base layer 112, that is, the second groove 152 is located on the front. Figure 1 The first groove 151 is indicated by a dashed line, which means that the first groove 151 is located on the back side when viewed from the second base layer 112 toward the first base layer 111.

[0062] A portion of the first busbar 141 is located on the surface of the second base layer 112 away from the first base layer 111, and another portion is located within the first groove 151 and contacts the bottom of the first groove 151 (i.e., the first conductive layer 121 within the first groove 151) to achieve electrical connection with the first conductive layer 121. A portion of the second busbar 142 is located on the surface of the first base layer 111 away from the second base layer 112, and another portion is located within the second groove 152 and contacts the bottom of the second groove 152 (i.e., the second conductive layer 122 within the second groove 152) to achieve electrical connection with the second conductive layer 122.

[0063] In this embodiment, the first busbar 141 is connected to the first conductive layer 121 at multiple points, and the second busbar 142 is connected to the second conductive layer 122 at multiple points, which is beneficial to improving the color-changing speed of the electrochromic film 10.

[0064] In one embodiment, see [reference] Figure 3 Along the width direction of the first busbar 141, the first busbar 141 and the groove wall of the first groove 151 have a first gap G1, and the first encapsulation layer 210 also covers the first gap G1. The first busbar 141 and the groove wall of the first groove 151 are spaced apart along the width direction, and the first encapsulation layer 210 covers the gap between the first busbar 141 and the first groove 151. In this embodiment, since the first encapsulation layer 210 covers or partially fills the first gap G1, during heat treatment, the first encapsulation layer 210 melts and fills the first gap G1, allowing the first encapsulation structure 211 to encapsulate the surface of the first busbar 141 near the groove wall of the first groove 151 along the width direction, and also to encapsulate the groove wall of the first groove 151 near the first busbar 141 along the width direction. This reduces the risk of functional components (especially electrolytes) in the electrochromic layer 130 leaking out, and inhibits the migration of leaked electrolytes and other functional components to the first busbar 141, reducing the risk of corrosion of the first busbar 141.

[0065] Similarly, in one embodiment, along the width direction of the second busbar 142, the second busbar 142 and the groove wall of the second groove 152 have a second gap G2, and the second encapsulation layer 220 also covers the second gap G2. The second busbar 142 and the groove wall of the second groove 152 are spaced apart along the width direction, and the second encapsulation layer 220 covers the gap between the second busbar 142 and the second groove 152. In this embodiment, since the second encapsulation layer 220 covers the second gap G2, during heat treatment, the second encapsulation layer 220 melts and fills the second gap G2, allowing the second encapsulation structure 221 to encapsulate the surface of the second busbar 142 near the groove wall of the second groove 152 along the width direction, and also to encapsulate the groove wall of the second groove 152 near the second busbar 142 along the width direction. This reduces the risk of functional components (especially electrolytes) in the electrochromic layer 130 leaking out, and inhibits the migration of leaked electrolytes and other functional components to the second busbar 142, reducing the risk of corrosion of the second busbar 142.

[0066] like Figure 3 As shown, in one embodiment, one end of the encapsulation layer extends beyond the edge of the electrochromic film 10, and the encapsulation layer can cover the peripheral surface of the electrochromic film 10 after being heat-melted. Specifically, the ends of the first encapsulation layer 210 and the second encapsulation layer 220 are disposed on the peripheral surface of the electrochromic film 10, overlapping each other, thereby encapsulating the peripheral surface of the electrochromic film 10.

[0067] In this process, the portion of the first encapsulation layer 210 extending beyond the edge of the electrochromic film 10 overlaps with the portion of the second encapsulation layer 220 extending beyond the edge of the electrochromic film 10. At this point, the first encapsulation layer 210 and the second encapsulation layer 220 can be bonded and fixed by heating, or by utilizing the inherent adhesiveness of either the first or second encapsulation layer 220. During heat treatment, the first and second encapsulation layers molten and coat the peripheral surface of the electrochromic film 10, preventing the peripheral surface of the electrochromic film 10 from being directly exposed to the environment. This prevents water and oxygen from entering the interior of the electrochromic film 10, reducing the risk of failure of the functional materials (such as the electrochromic material) inside the electrochromic layer 130 and improving the service life of the electrochromic film 10.

[0068] In one embodiment, the first encapsulation layer 210 becomes adhesive after melting and is bonded to the first surface of the electrochromic film 10 by heating, thus completely covering the first busbar 141. In another embodiment, the second encapsulation layer 220 becomes adhesive after melting and is bonded to the second surface of the electrochromic film 10 by heating, thus completely covering the second busbar 142. The materials of the first encapsulation layer 210 and the second encapsulation layer 220 are not adhesive at room temperature and need to be heated to a specific temperature to melt them, and then cooled to form an adhesive bond. For example, the materials of the first encapsulation layer 210 and the second encapsulation layer 220 can be POE. When preparing the electrochromic film 10, the first encapsulation layer 210 and the second encapsulation layer 220 can be partially melted by heating to form a fixed and preliminary encapsulation on the surfaces of the first busbar 141 and the second busbar 142. In subsequent applications, reheating completely melts the first encapsulation layer 210 and the second encapsulation layer 220, forming a complete seal for the first busbar 141 and the second busbar 142.

[0069] Please see Figure 5 In one embodiment, the thickness of the encapsulation layer is greater than or equal to the thickness of the electrochromic film. Specifically, the total thickness of the first encapsulation layer 210 and the second encapsulation layer 220 is greater than or equal to the thickness of the electrochromic film 10. The total thickness of the encapsulation structure formed after the first encapsulation layer 210 and the second encapsulation layer 220 melts is greater than or equal to the thickness of the electrochromic film 10, which can reliably seal the busbar. When the first encapsulation layer 210 and the second encapsulation layer 220 also cover the first groove 151 and the second groove 152, the encapsulation structure formed after melting can also substantially fill the grooves, forming an effective and reliable seal for the grooves. This not only prevents water and oxygen in the environment from eroding the electrochromic film 10 through the second groove 152, but also inhibits the leakage of functional materials (especially electrolytes) inside the electrochromic layer 130 from the grooves.

[0070] Before use, the flexible electrochromic film 10 typically needs to be laminated with a substrate, such as glass, to form an electrochromic device. This is done by fixing the electrochromic film 10 between two pieces of glass using an adhesive layer. The total thickness of the first encapsulation layer 210 and the second encapsulation layer 220 is greater than or equal to the thickness of the electrochromic film 10, resulting in a more uniform overall thickness. The portion of the encapsulation layer that is thicker than the functional layer can be eliminated during high-temperature melting, which helps reduce the risk of lamination cracking.

[0071] Please see Figure 5In one embodiment, along the thickness direction of the electrochromic film 10, the surface of the first encapsulation structure 211 facing away from the first conductive layer 121 is flush with, or protrudes from, the surface of the second base layer 112 facing away from the first conductive layer 121. This facilitates reliable encapsulation of the first busbar 141 and the first groove 151 and reduces the risk of chip breakage during subsequent lamination.

[0072] Please see Figure 5 In one embodiment, along the thickness direction of the electrochromic film 10, the surface of the second encapsulation structure 221 facing away from the second conductive layer 122 is flush with the surface of the first base layer 111 facing away from the second conductive layer 122, or protrudes from the surface of the first base layer 111 facing away from the second conductive layer 122. This facilitates reliable encapsulation of the first busbar 141 and the first groove 151 and reduces the risk of chip breakage during subsequent lamination.

[0073] In one embodiment, the ends of the first encapsulation layer 210 and / or the second encapsulation layer 220 extend beyond the edge of the electrochromic film 10 by W centimeters, where W is greater than or equal to 2. The width of the first encapsulation layer 210 extending beyond the edge of the functional layer is greater than or equal to 2 cm. During the fabrication of the electrochromic device using the electrochromic film 10, it is not necessary to additionally place a sealing ring layer 40 around the periphery of the electrochromic film 10 (see reference). Figure 6 The edge of the electrochromic film 10 can be sealed using only the first encapsulation layer 210 and the second encapsulation layer 220, thereby simplifying the fabrication of the electrochromic device.

[0074] In one embodiment, the surface of the busbar is further covered with a waterproof layer, and an encapsulation layer covers the waterproof layer.

[0075] In one embodiment, the first encapsulation layer 210 is adhesive at room temperature and is bonded to the surface of the waterproof layer. In another embodiment, the second encapsulation layer 220 is adhesive at room temperature and is bonded to the surface of the waterproof layer. The materials of the first and second encapsulation layers 210 and 220 themselves have a certain degree of adhesiveness at room temperature. The first and second encapsulation layers 210 and 220 are bonded to the surface of the waterproof layer by their own adhesiveness. In subsequent applications, heat treatment is used to completely melt the encapsulation layers to form an encapsulation structure. Alternatively, before application, to increase the reliability of the connection between the first and second encapsulation layers 210 and 220 and the electrochromic film 10, the first and second encapsulation layers 210 and 220 can be partially melted by heating, and then completely melted by reheating in subsequent applications to form an encapsulation.

[0076] Please see Figure 5This application also provides an electrochromic device 1, which includes a first substrate 21, an electrochromic film 10, a second substrate 22, and an adhesive layer disposed between the first substrate 21 and the electrochromic film 10 and between the second substrate 22 and the electrochromic film 10. Specifically, the adhesive layer includes a first adhesive layer 31 disposed between the first substrate 21 and the electrochromic film 10 and a second adhesive layer 32 disposed between the first substrate 21 and the electrochromic film 10 and between the second substrate 22 and the electrochromic film 10.

[0077] The busbars on both opposite surfaces of the electrochromic film 10 are covered with an encapsulation structure. The encapsulation structure is at least one of a non-polar material layer, a polyolefin layer, an epoxy system material layer, a POE layer, and a PIB layer; the material of the encapsulation structure is different from the material of the adhesive layer. The encapsulation structure includes a first encapsulation structure 211 covering the first busbar 141 and a second sealing structure 221 covering the second busbar 142.

[0078] Generally, when fabricating an electrochromic device 1, a first substrate 21, a first adhesive layer 31, an electrochromic film 10, a second adhesive layer 32, and a second substrate 22 can be sequentially stacked. The stacked layers are then heat-treated to obtain the electrochromic device 1. During heat treatment, the electrochromic film 10 forms an encapsulation structure for the busbar to protect it.

[0079] In other embodiments, the electrochromic film 10 may be heat-treated first, and then stacked with other layers to form the electrochromic device 1. Alternatively, the electrochromic film 10 may be heat-treated first, and then stacked with other layers, followed by a second heat treatment of the stack.

[0080] The first adhesive layer 31 is used to bond the first substrate 21 and the electrochromic film 10, and the second adhesive layer 32 is used to bond the electrochromic film 10 and the second substrate 22. Exemplarily, the first adhesive layer 31 and the second adhesive layer 32 can be made of polyvinyl butyral (PVB), ethylene-vinyl acetate copolymer (EVA), etc. In one embodiment, the first adhesive layer 31 and the second adhesive layer 32 can also be made of POE, PIB, epoxy system materials, butyl rubber system materials, or other non-polar materials with stronger sealing performance and effective ion penetration blocking capabilities.

[0081] The electrochromic film 10 is bonded between the first substrate 21 and the second substrate 22 through two adhesive layers, which can improve the stability of the electrochromic film 10, protect it from the influence of water and oxygen that could cause the electrochromic device 1 to fail, make the electrochromic device 1 more stable, extend its service life, and make the electrochromic device 1 more robust, so that it can be applied to automotive glass, architectural glass and other scenarios.

[0082] In one implementation, such as Figure 6 As shown, if the thickness of the first encapsulation layer 210 and the second encapsulation layer 220 is small and does not exceed the edge of the electrochromic film 10 or exceeds the edge of the functional stack by a small amount, the first encapsulation layer 210 and the second encapsulation layer 220 are insufficient to encapsulate the peripheral surface of the electrochromic film 10. In this case, in order to achieve a seal on the peripheral surface of the electrochromic film 10, the size of the electrochromic film 10 is usually set to be smaller than the adhesive layer and the substrate. When laminating, in addition to stacking the first substrate 21, the first adhesive layer 31, the electrochromic film 10, the second adhesive layer and the second substrate 22, a sealing ring layer 40 in a roughly "U" shape is also required on the outside of the electrochromic film 10, between the first adhesive layer 31 and the second adhesive layer. After the sealing ring layer 40 melts and cools, it seals the peripheral surface of the electrochromic film 10. The sealing ring 40 can be made of PVB or EVA, or it can be made of POE, PIB, epoxy system materials, butyl rubber system materials or other non-polar materials that have stronger sealing performance and can effectively block ion penetration.

[0083] In one embodiment, the surface of the first busbar 141 near the first conductive layer 121 is connected to the first conductive layer 121 or the second base layer 112, and the remaining surface of the first busbar 141 is encapsulated by a first sealing structure, thereby isolating the first busbar 141 from the external environment, reducing the risk of the first busbar 141 failing due to water, oxygen, or ion erosion, and improving the service life of the electrochromic film 10.

[0084] In one embodiment, the surface of the second busbar 142 near the second conductive layer 122 is connected to the second conductive layer 122 or the first base layer 111, and the remaining surface of the second busbar 142 is encapsulated by a second sealing structure, thereby isolating the second busbar 142 from the external environment, reducing the risk of the second busbar 142 failing due to water, oxygen, or ion erosion, and also reducing the risk of ion leaching corrosion of the second busbar 142 in the electrochromic layer 130, which is beneficial to improving the service life of the electrochromic film 10.

[0085] In one embodiment, the resistivity of the encapsulation structure is greater than that of the adhesive layer or the PVB material. In this embodiment, the encapsulation structure has a large resistivity, which can significantly suppress ion migration behavior, giving the encapsulation structure excellent encapsulation protection performance. This helps reduce the risk of ion leaching and corrosion of the busbar in the electrochromic layer 130, and also helps reduce the risk of external substances such as water and oxygen eroding the busbar through the encapsulation structure, thereby improving the service life of the electrochromic film 10.

[0086] In one embodiment, the resistivity of the package structure is greater than 10. 16 Ω·cm.

[0087] In one embodiment, the ion migration rate of the encapsulation structure is lower than that of the adhesive layer or PVB material. In this embodiment, the encapsulation structure has a lower ion migration rate, which can effectively suppress ion permeation from the electrochromic layer 130 and diffusion to the busbar, reducing the risk of busbar open circuit or failure.

[0088] Please see Figure 5 In one embodiment, the thickness of the encapsulation structure is greater than or equal to the thickness of the electrochromic film 10. The larger thickness of the encapsulation structure allows for a reliable seal on the busbar. When the encapsulation structure also covers the groove, it can substantially fill the groove, forming an effective and reliable seal. This not only prevents water and oxygen in the environment from eroding the electrochromic film 10 through the groove, but also inhibits the leakage of functional materials (especially electrolytes) inside the electrochromic layer 130 from the groove.

[0089] In one embodiment, the yellowing index ΔYI of the encapsulation structure is less than or equal to 3, which makes the encapsulation structure less prone to yellowing during long-term use, especially during use in environments with long-term light exposure, high temperature, and high humidity, so that the electrochromic device can maintain a good appearance.

[0090] This application also provides a method for fabricating an electrochromic device. The fabrication method is illustrated below using the fabrication of electrochromic device 1 as an example.

[0091] Please see Figure 7 The method for preparing the electrochromic device 1 includes:

[0092] S100, providing or preparing an electrochromic film 10. Busbars on opposite surfaces of the electrochromic film 10 are covered with an encapsulation layer.

[0093] S200, under the first process conditions, at least a portion of the encapsulation layer is melted to form an encapsulation structure for sealing the busbar.

[0094] S300, a first substrate 21, an electrochromic film 10, and a second substrate 22 are stacked, and an adhesive layer is provided between the first substrate 21 and the electrochromic film 10 and between the second substrate 22 and the electrochromic film 10 (see reference). Figure 5 and Figure 6 ).

[0095] S400, under the second process conditions, melts the bonding layer and the encapsulation structure to form an electrochromic device.

[0096] In this embodiment, in step S100, the busbar is initially sealed with an encapsulation layer, which reduces the risk of the busbar failing due to corrosion by water, oxygen, chemical reagents, etc., during short-term storage and transportation of the electrochromic film 10, thus facilitating the storage and transportation of the electrochromic film 10. Simultaneously, the encapsulation layer also provides a certain degree of physical fixation for the busbar, improving the reliability of the electrical connection between the busbar and the conductive layer, etc.

[0097] In addition, the encapsulation structure formed by the encapsulation layer being at least partially melted under the first process conditions is in close contact with the busbar, which can better block water, oxygen, chemical reagents, etc.

[0098] In the second process condition treatment of step S400, the encapsulation structure is remelted. On the one hand, the encapsulation layer that was not completely melted in the first process condition treatment stage can be completely melted in the post-processing stage to form the encapsulation structure, which can better seal and isolate the busbar. On the other hand, the melting of both the encapsulation layer and the adhesive layer is beneficial to improving the interface appearance between the encapsulation layer and the adhesive layer, and enhancing the bonding force between them. Furthermore, the encapsulation layer undergoes the first process condition treatment first, and then the adhesive layer undergoes the first process condition treatment, which can reduce the stress caused by the difference in expansion rate in the junction area between the encapsulation layer and the adhesive layer, thereby reducing the problem of film delamination or even cracking of the electrochromic device 1.

[0099] In one embodiment, the first process conditions include a first temperature, a first pressure, and a first time, and the second process conditions include a second temperature, a second pressure, and a second time, wherein the first process conditions differ from the second process conditions and satisfy at least one of the following conditions:

[0100] The first temperature is lower than the second temperature;

[0101] The first pressure is less than the second pressure.

[0102] The first time is less than the second time.

[0103] In this embodiment, the pretreatment process employs easily achievable conditions such as low temperature, low pressure, and short time, which simplifies operation and reduces process costs. Furthermore, the encapsulation layer is fixed to the surface of the electrochromic film 10 during the first process condition treatment, and the encapsulation structure formed by at least partial melting can initially isolate the busbar from the outside environment, thus providing initial protection for the busbar.

[0104] The second process condition involves high temperature, high pressure, and long duration to ensure that the encapsulation layer and adhesive layer are fully melted, so as to better encapsulate and protect the busbar.

[0105] Furthermore, when the adhesive layer and encapsulation layer are made of different materials, for example, when the adhesive layer is PVB and the encapsulation layer is POE, the lamination processes of POE and PVB are incompatible. PVB uses an autoclave process, while POE requires low-temperature vacuum lamination, resulting in significant differences in temperature, pressure, and heating rate requirements. If the same parameters are used for lamination, i.e., step S200 is omitted and the encapsulation layer is heat-treated only in step S400, it can easily lead to bubbles, film wrinkles, or glass breakage in the POE area. To avoid such defects, in this embodiment, the electrochromic film 10 is first subjected to a first process condition treatment, i.e., the POE-containing electrochromic film 10 is pre-pressed at a relatively low temperature using a laminator in the initial stage, so that the POE partially melts and adheres to the film surface, and the busbar position is initially encapsulated. The PVB module is then combined for a second process condition treatment, and the final lamination is completed using an autoclave. This process effectively avoids the stress caused by the difference in expansion rate between PVB and POE in the interface area, thereby reducing the risk of electrochromic device 1 delamination or even cracking.

[0106] In one embodiment, the first temperature is 90°C-120°C. At this temperature, the encapsulation layer can at least partially melt, thereby bonding and fixing it to the surface of the electrochromic film 10.

[0107] In one embodiment, the first pressure is 0.1 MPa-0.5 MPa, which is beneficial for the bonding of the encapsulation layer to the surface of the electrochromic film 10.

[0108] In one embodiment, the initial processing time is 2-10 minutes. A shorter pretreatment time simplifies the process and reduces costs.

[0109] In one embodiment, the second temperature is 135°C-150°C, which is conducive to the complete melting of the encapsulation layer and the adhesive layer.

[0110] In one embodiment, the second pressure is 0.8 MPa-1.2 MPa, which is beneficial for the bonding of the encapsulation layer to the busbar and the adhesive layer to the electrochromic film 10.

[0111] In one embodiment, the second time is 8h-12h, which is beneficial for the bonding of the encapsulation layer with the busbar and the adhesive layer with the electrochromic film 10.

[0112] In one embodiment, the encapsulation layer undergoes pre-crosslinking during the pretreatment process. Two pre-crosslinked encapsulation layers can then be bonded together to provide initial sealing for each electrode. Specifically, during the pretreatment stage, the encapsulation layer material is at least partially melted and partially pre-crosslinked, resulting in an encapsulation structure with improved temperature resistance. For example, when the encapsulation layer material is POE, POE begins to melt at approximately 90°C, and the temperature resistance of the crosslinked POE is approximately 140°C-180°C.

[0113] In one embodiment, the melting temperature difference between the encapsulation structure and the adhesive layer is less than the melting temperature difference between the encapsulation layer and the adhesive layer. After the first process condition treatment, the melting temperature of the encapsulation structure is close to the melting temperature of the adhesive layer. When the encapsulation structure and the adhesive layer are subsequently treated together with the first process condition treatment, the risk of bubbles, wrinkles, etc., forming in the contact area between the adhesive layer and the encapsulation structure can be reduced.

[0114] In one embodiment, the melting temperature of the encapsulation layer is lower than that of the adhesive layer. In this embodiment, the encapsulation layer has a lower melting temperature, allowing it to melt and form the encapsulation structure at a lower temperature, thus reducing the heat treatment temperature.

[0115] Please see Figure 5 In one embodiment, along the thickness direction of the electrochromic film 10, the orthographic projections of the first substrate 21, the first adhesive layer 31, the electrochromic film 10, and the second adhesive layer 32 on the second substrate 22 coincide with the second substrate 22. This arrangement makes the peripheral surface of the electrochromic device 1 flush, which helps to reduce the size of the electrochromic device 1 and facilitates its use. In addition, during the fabrication of the electrochromic device 1 from the electrochromic film 10, it is not necessary to place an additional sealing ring layer 40 on the peripheral surface of the electrochromic film 10, simplifying the fabrication of the electrochromic device 1.

[0116] Please see Figure 5 In one embodiment, along the thickness direction of the electrochromic film 10, the peripheral surfaces of the first substrate 21, the adhesive layer, the electrochromic film 10, and the second substrate 22 are flush with each other. This arrangement makes the sidewalls of each stack used to fabricate the electrochromic device 1 flush, which helps to simplify the fabrication process of the electrochromic device, ensures uniform stress among the stacks, and reduces the risk of cracking of the electrochromic device 1.

[0117] Please see Figure 6In one embodiment, the projection of the electrochromic film 10 lies within the projection of the adhesive layer along the thickness direction of the electrochromic film 10. The size of the electrochromic film 10 is smaller than the size of the adhesive layer.

[0118] Please see Figure 6 In one embodiment, the preparation method further includes: disposing a sealing ring layer 40 made of the same material as the adhesive layer between the first substrate 21 and the second substrate 22, the sealing ring layer 40 surrounding the electrochromic film; and

[0119] Under the second process conditions, the sealing ring layer is melted, so that it cooperates with the adhesive layer and the encapsulation structure to cover the electrochromic film 10.

[0120] In this embodiment, the use of a sealing ring 40 can reduce the risk of cracking and better seal the electrochromic film 10.

[0121] In one embodiment, the resistivity of the encapsulation layer is greater than that of the adhesive layer or the PVB material. Furthermore, the resistivity of the encapsulation structure formed after pretreatment of the encapsulation layer is also greater than that of the adhesive layer or the PVB material. In this embodiment, the encapsulation layer has a high resistivity, which significantly suppresses ion migration behavior, resulting in excellent encapsulation protection performance. This helps reduce the risk of ion leaching and corrosion of the busbars in the electrochromic layer 130, and also helps reduce the risk of external substances such as water and oxygen eroding the busbars through the adhesive layer and encapsulation layer, thereby improving the service life of the electrochromic film 10.

[0122] In one embodiment, the ion migration rate of the encapsulation layer is lower than that of the adhesive layer or the PVB material. Specifically, the ion migration rate of the encapsulation structure formed after pretreatment of the encapsulation layer is lower than that of the adhesive layer or the PVB material.

[0123] In this embodiment, the encapsulation layer has a low ion migration rate, which can effectively suppress ion permeation from the electrochromic layer 130 and diffusion to the busbar, reducing the risk of busbar open circuit and failure.

[0124] Please see Figure 5 In one embodiment, the thickness of the encapsulation layer is greater than or equal to the thickness of the electrochromic film 10. The encapsulation structure formed after the encapsulation layer melts is relatively thick, which can reliably seal the busbar. When the encapsulation layer also covers the groove, the encapsulation structure formed after melting can also substantially fill the groove, forming an effective and reliable seal for the groove. This not only prevents water and oxygen in the environment from corroding the electrochromic film 10 through the groove, but also inhibits the leakage of functional materials (especially electrolytes) inside the electrochromic layer 130 from the groove.

[0125] When the electrochromic film 10 is used to fabricate the electrochromic device 1 with the substrate, adhesive layer, etc., the thickness of the encapsulation layer is greater than or equal to the thickness of the electrochromic film 10, so that the overall thickness of the electrochromic film 10 is relatively uniform. The part of the encapsulation layer that is thicker than the functional layer can be eliminated when it is melted at high temperature, which helps to reduce the risk of chip breakage during lamination.

[0126] In one embodiment, the encapsulation layer is made of a non-polar material. The non-polar material is selected from at least one of POE, PIB (polyisobutylene), and epoxy resin.

[0127] In one embodiment, the encapsulation layer material is selected from at least one of polyolefin materials and epoxy-based materials. The polyolefin materials include at least one of POE and butyl rubber-based materials. The butyl rubber-based materials include PIB (polyisobutylene).

[0128] In one embodiment, the materials of the first encapsulation layer 210 and the second encapsulation layer 220 include at least one of POE and PIB.

[0129] Polyolefin materials (such as POE and PIB), epoxy materials, and butyl rubber materials all have good isolation properties. In particular, POE and PIB materials have excellent isolation properties. In the embodiments of this application, the material of the encapsulation layer is limited, which can better isolate the busbar from water and oxygen, reduce the risk of busbar corrosion, and POE and PIB materials have excellent mechanical stress buffering ability, reducing the risk of poor overlap between the busbar and the conductive layer due to stress. This helps to reduce the risk of busbar failure and improve the service life of the electrochromic film 10.

[0130] In one embodiment, the adhesive layer is made of at least one of POE and PVB. When POE is used as the adhesive layer material, POE has good isolation properties that can further protect the electrochromic film 10. When PVB is used as the adhesive layer material, PVB is inexpensive and has certain encapsulation capabilities, which helps to reduce the cost of the electrochromic device 1.

[0131] In one embodiment, the surface of the busbar is covered with waterproof tape, and an encapsulation layer is also covered with waterproof tape. This double encapsulation of the busbar with waterproof tape and an encapsulation layer reduces the risk of corrosion.

[0132] Please see Figures 1 to 3In one embodiment, the electrochromic film 10 further has a groove, and at least a portion of the busbar is electrically connected to a conductive layer exposed within the groove; the busbar and the groove wall have a gap. Specifically, the first busbar 141 and the groove wall of the first groove 151 have a first gap G1. Along the width direction of the second busbar 142, the second busbar 142 and the groove wall of the second groove 152 have a second gap G2.

[0133] The method for preparing the electrochromic device 1 further includes: covering the gap with an encapsulation layer, and filling the gap with at least part of the encapsulation structure after melting under the first process conditions.

[0134] Specifically, the first encapsulation layer 210 also covers the first gap G1, and after processing under the first process conditions, at least part of the first encapsulation structure 211 fills the first gap G1.

[0135] The second encapsulation layer 220 also covers the second gap G2, and at least part of the second encapsulation structure 221 fills the second gap G2 after the first process condition treatment.

[0136] In this embodiment of the application, since the encapsulation structure fills the gap, the encapsulation structure can encapsulate the surface of the busbar close to the groove wall along the width direction, and can also encapsulate the groove wall close to the busbar along the width direction.

[0137] The above settings reduce the risk of leakage of functional components (especially electrolytes) in the electrochromic layer 130, and inhibit the migration of leaked functional components such as electrolytes to the busbar, thereby reducing the risk of busbar corrosion.

[0138] It should be understood that, although Figure 7 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 7 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0139] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0140] The above descriptions merely illustrate several implementation methods of the embodiments of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the embodiments of this application, and these modifications and improvements all fall within the protection scope of the embodiments of this application. Therefore, the protection scope of the patent embodiments of this application should be determined by the appended claims.

Claims

1. An electrochromic film, characterized in that, The electrochromic film includes busbars disposed on its two opposite surfaces and an encapsulation layer covering the busbars. The encapsulation layer, after being at least partially melted, can form an encapsulation structure for sealing the busbars. The encapsulation layer is at least one of a non-polar material layer, a polyolefin layer, an epoxy system material layer, a POE layer, and a PIB layer.

2. The electrochromic film according to claim 1, characterized in that, The resistivity of the encapsulation layer is greater than that of the PVB; and / or The ion migration rate of the encapsulation layer is less than that of the PVB; and / or The thickness of the encapsulation layer is greater than or equal to the thickness of the electrochromic film; and / or The resistivity of the encapsulation layer is greater than 10. 16 Ω·cm; and / or The yellowing index ΔYI of the encapsulation layer is less than or equal to 3.

3. The electrochromic film according to claim 1, characterized in that, One end of the encapsulation layer extends beyond the edge of the electrochromic film, and the encapsulation layer can cover the periphery of the electrochromic film after being heat-melted.

4. The electrochromic film according to claim 1, characterized in that, The surface of the busbar is also covered with a waterproof layer, and the encapsulation layer covers the waterproof layer.

5. The electrochromic film according to claim 4, characterized in that, The encapsulation layer is adhesive at room temperature and adheres to the surface of the waterproof layer.

6. An electrochromic device, comprising a first substrate, an electrochromic film, a second substrate, and an adhesive layer disposed between the first substrate and the electrochromic film and between the second substrate and the electrochromic film, characterized in that, The busbars on the opposite surfaces of the electrochromic film are covered with an encapsulation structure, which is at least one of a non-polar material layer, a polyolefin layer, an epoxy system material layer, a POE layer, and a PIB layer. The material of the encapsulation structure is different from the material of the adhesive layer.

7. The electrochromic device according to claim 6, characterized in that, The material of the adhesive layer is selected from at least one of POE and PVB.

8. The electrochromic device according to claim 6, characterized in that, The resistivity of the encapsulation structure is greater than the resistivity of the adhesive layer or PVB; and / or The ion migration rate of the encapsulation structure is lower than that of the adhesive layer or PVB. and / or The thickness of the encapsulation structure is greater than or equal to the thickness of the electrochromic film; and / or the resistivity of the encapsulation structure is greater than 10. 16 Ω·cm; and / or The yellowing index ΔYI of the encapsulation structure is less than or equal to 3.

Images