Electrochromic device

Abstract

This application discloses an electrochromic device, relating to the field of electronic device components. The electrochromic device includes a substrate, a metal mesh conductive layer, and an electrochromic layer. A recessed region is formed on the surface of the substrate; the metal mesh conductive layer is disposed within the recessed region and does not protrude from the surface of the substrate; the electrochromic layer is disposed on the side of the metal mesh conductive layer away from the substrate and is electrically connected to the metal mesh conductive layer; wherein the metal mesh conductive layer includes a plurality of sequentially stacked sub-conductive layers. The electrochromic device provided by this application exhibits both good conductivity and weather resistance.

Description

Technical Field

[0001] This application relates to the field of electrochromic technology, and more particularly to an electrochromic device. Background Technology

[0002] An electrochromic device is a material or device that can change its optical properties (such as transparency or color) by applying an external electric field.

[0003] In related technologies, by using a metal mesh process to increase the thickness of the metal component and reduce the sheet resistance of the metal mesh, electrochromic devices can achieve faster and more uniform color-changing effects.

[0004] Embedded metal meshes are typically placed within recesses in a substrate. Their fabrication involves filling the recesses with a slurry and then curing the slurry. After curing, the material shrinks, especially in areas of stress concentration, making it prone to cracking. Summary of the Invention

[0005] In view of this, this application provides an electrochromic device, which aims to solve one of the technical problems in the prior art.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0007] In a first aspect, embodiments of this application provide an electrochromic device, comprising:

[0008] The substrate has recessed areas formed on its surface;

[0009] A metal mesh conductive layer is disposed within the recessed area and does not protrude from the surface of the substrate;

[0010] An electrochromic layer is disposed on the side of the metal mesh conductive layer away from the substrate and is electrically connected to the metal mesh conductive layer;

[0011] The metal mesh conductive layer comprises multiple sub-conductive layers stacked sequentially.

[0012] In one embodiment of the first aspect, the metal mesh includes N sub-conductive layers, where N is a positive integer greater than or equal to 2 and less than or equal to 10. The metal mesh includes 2 to 10 sub-conductive layers; exemplarily, the number of sub-conductive layers can be 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0013] Along the direction from the substrate to the electrochromic layer, the thickness of the N sub-conductive layers gradually decreases. Specifically, the thickness of the sub-conductive layer is smaller the closer it is to the electrochromic layer.

[0014] In one embodiment of the first aspect, the conductivity of the plurality of sub-conductive layers gradually decreases along the direction from the substrate toward the electrochromic layer. Specifically, the conductivity of the sub-conductive layers closer to the electrochromic layer is lower.

[0015] In one embodiment of the first aspect, the density of the plurality of sub-conductive layers gradually increases along the direction from the substrate toward the electrochromic layer. Specifically, the density of the sub-conductive layers closer to the electrochromic layer is higher.

[0016] In one embodiment of the first aspect, along the direction from the substrate to the electrochromic layer, the sub-conductive layer near the electrochromic layer is configured to prevent metal ions in the sub-conductive layer near the substrate from precipitating toward the electrochromic layer.

[0017] In one embodiment of the first aspect, the sub-conductive layer contains a weather-resistant material, and the content of the weather-resistant material in the plurality of sub-conductive layers gradually increases along the direction from the substrate to the electrochromic layer.

[0018] In one embodiment of the first aspect, when the sub-conductive layer is provided with a weather-resistant material, the weather-resistant material is at least one of Ni, Pb, Au and Pt.

[0019] In one embodiment of the first aspect, the recessed region includes a plurality of intersecting grooves, the width of the grooves being 5μm-20μm and the depth of the grooves being 5μm-20μm.

[0020] In one embodiment of the first aspect, the electrochromic device further includes a protective layer disposed on the surface of the substrate near the electrochromic layer and covering the recessed area, the protective layer being electrically connected to the metal mesh conductive layer.

[0021] In one embodiment of the first aspect, the conductivity of the metal mesh conductive layer is greater than that of the protective layer.

[0022] In one embodiment of the first aspect, the protective layer is configured to prevent chemical reaction with the conductive metal mesh layer.

[0023] In one embodiment of the first aspect, the protective layer includes at least one sub-protective layer, which is a transparent and conductive sub-protective layer.

[0024] In one embodiment of the first aspect, the protective layer comprises M sub-protective layers, where M is a positive integer not exceeding 4.

[0025] In one embodiment of the first aspect, the protective layer includes at least one of a first sub-protective layer and a second sub-protective layer, wherein the first sub-protective layer includes any one of ITO, AZO, and ZnO, and the second sub-protective layer includes any one of PEDOT:PSS, P3HT, PDDT, PPV, graphene, and carbon nanotubes.

[0026] In one embodiment of the first aspect, the substrate, the first sub-protective layer, the second sub-protective layer, and the electrochromic layer are stacked sequentially.

[0027] In one embodiment of the first aspect, the thickness of the first sub-protective layer is 100-200 nm; the thickness of the second sub-protective layer is 500-2000 nm.

[0028] In one embodiment of the first aspect, the substrate includes a first base layer, a second base layer, and a third base layer stacked sequentially, wherein:

[0029] The recessed region is formed on the surface of the first substrate layer away from the second substrate layer, and the metal mesh conductive layer is disposed on the surface of the first substrate layer. The first substrate layer includes resin.

[0030] The second base layer includes at least one of a hardening layer, an anti-reflection layer, a heat insulation layer, and a heating layer;

[0031] The third substrate layer includes at least one of a glass substrate and PET.

[0032] In one embodiment of the first aspect, the electrochromic device includes two substrates and two metal mesh conductive layers, the two metal mesh conductive layers being disposed in the recessed regions of the two substrates respectively, the electrochromic layers being arranged between the two metal mesh conductive layers, and the two oppositely arranged surfaces of the electrochromic layers being electrically connected to the two metal mesh conductive layers respectively.

[0033] Secondly, embodiments of this application also provide a method for manufacturing an electrochromic device, comprising:

[0034] A substrate is provided, and a grid-like recessed area is formed on one surface of the substrate;

[0035] Sub-conductive layers are sequentially fabricated from the inside out in the recessed region to form a metal mesh conductive layer with multiple sub-conductive layers; and

[0036] An electrochromic layer is fabricated on a conductive metal mesh layer.

[0037] Compared to existing technologies, the advantages of this application are as follows: This application proposes an electrochromic device, including a substrate, a metal mesh conductive layer, and an electrochromic layer. A recessed region is formed on the surface of the substrate. The metal mesh conductive layer is disposed within the recessed region and does not protrude from the surface of the substrate. The electrochromic layer is disposed on the side of the metal mesh conductive layer away from the substrate and is electrically connected to the metal mesh conductive layer. By applying a voltage to the metal mesh conductive layer, the optical state of the electrochromic layer can be changed, causing the device with this electrochromic device to exhibit reversible changes in color and transparency. The metal mesh conductive layer has high electrical conductivity, which is beneficial for accelerating the color-changing rate of the electrochromic device.

[0038] Generally, the metal mesh conductive layer is formed by curing a filler material within the recessed area. The metal mesh conductive layer comprises multiple sequentially stacked sub-conductive layers, which effectively suppresses the risk of cracking at the edges of the recessed area after the filler material has cured within the recessed area.

[0039] In addition, setting multiple sub-conductive layers helps the metal mesh conductive layer to fill the recessed area as much as possible, thereby increasing the filling rate of the recessed area. The increased film thickness of the metal mesh conductive layer helps to reduce the sheet resistance of the metal mesh conductive layer and improve its conductivity. Attached Figure Description

[0040] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 The following are schematic diagrams illustrating the structure of electrochromic devices provided in some embodiments of this application;

[0042] Figure 2 It shows Figure 1 Enlarged view of point I in the middle;

[0043] Figure 3 A flowchart illustrating the fabrication process of an electrochromic device provided in some embodiments of this application is shown.

[0044] Key component symbols: 100 - Electrochromic device; 110 - Substrate; 111 - First base layer; 112 - Second base layer; 113 - Third base layer; 114 - Recessed area; 120 - Metal mesh conductive layer; 121 - Sub-conductive layer; 130 - Protective layer; 131 - First sub-protective layer; 132 - Second sub-protective layer; 1141 - Groove; 140 - Electrochromic layer; 141 - Electrochromic material layer; 142 - Electrolyte layer; 143 - Ion storage layer. Detailed Implementation

[0045] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0046] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing 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, and therefore should not be construed as a limitation of this application.

[0047] 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 one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0048] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0049] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0050] Electrochromic devices are widely used in smart windows, automotive glass, display devices, mobile terminals and other fields, and have good market application prospects.

[0051] Electrochromic technology is the phenomenon that the optical properties (reflectivity, transmittance, absorptivity, etc.) of electrochromic materials undergo stable and reversible color changes under the action of an external electric field. In appearance, this manifests as reversible changes in color and transparency. Devices containing electrochromic materials are called electrochromic devices.

[0052] Electrochromic devices in related technologies typically include a first conductive layer, an electrochromic layer, and a second conductive layer stacked sequentially. Applying a voltage between the first and second conductive layers alters the optical state of the electrochromic layer, causing devices equipped with this electrochromic device to exhibit reversible changes in color and transparency. Reducing the resistance of the conductive layer plays a crucial role in achieving faster color-changing speeds and more uniform color-changing effects.

[0053] In related technologies, using a metal mesh as a conductive layer can reduce the resistance of the conductive layer. The general process for preparing a metal mesh is as follows: interlaced grooves are made on the surface of a substrate, conductive paste flows and fills the grooves, and after filling, the conductive paste solidifies to form a metal mesh-like conductive layer.

[0054] Because the slurry shrinks during curing, the cured conductive layer will have pits. This results in large unfilled spaces within the pits, reducing the film thickness and uniformity of the conductive layer and affecting the electrical connection between the conductive layer and the electrochromic layer. Furthermore, the presence of these pits can cause stress concentration at the junction of the cured conductive slurry and the pit walls, leading to cracking.

[0055] To solve the above problems, such as Figure 1 and Figure 2 As shown, an embodiment of this application provides an electrochromic device 100. The electrochromic device 100 includes a substrate 110, a plurality of metal mesh conductive layers 120, and an electrochromic layer 140.

[0056] The substrate 110 has a recessed area 114 on its surface, and the metal mesh conductive layer 120 is disposed in the recessed area 114 and does not protrude from the surface of the substrate 110, forming an embedded structure.

[0057] The electrochromic layer 140 is disposed on the side of the metal mesh conductive layer 120 away from the substrate 110 and is electrically connected to the metal mesh conductive layer 120. By applying a voltage to the metal mesh conductive layer 120, the optical state of the electrochromic layer 140 can be changed, so that the device having the electrochromic device 100 exhibits reversible changes in color and transparency in appearance.

[0058] The metal mesh conductive layer 120 of this application includes a plurality of sub-conductive layers 121 stacked sequentially.

[0059] In one embodiment, the fabrication process of the metal mesh conductive layer 120 is as follows:

[0060] A first coating is applied to the bottom of the recessed region 114. After the first coating has cured, a second coating is applied to the surface of the cured material. After the second coating has cured, a third coating is applied to the surface of the cured material, and so on, to form a multilayer sub-conductive layer 121. In one embodiment, the multilayer sub-conductive layer 121 fills the recessed region 114, that is, the surface of the sub-conductive layer 121 formed by the last coating is approximately flush with the opening of the recessed region 114.

[0061] As mentioned above, the metal mesh conductive layer 120 requires multiple "coating-curing" processes during its fabrication. Due to the sequential curing order of the two coating materials, there is a clear boundary between the two cured layers, causing the metal mesh conductive layer 120 to exhibit layered characteristics, thus forming the sub-conductive layer 121 of this application.

[0062] It should be noted that the materials used in the previous "coating-curing" process and the materials used in the subsequent "coating-curing" process may be the same or different.

[0063] When they are identical, each sub-conductive layer 121 is made of the same material, and the sub-conductive layers 121 are tightly bonded together. For example... Figure 2 As shown, this is equivalent to dividing the conductive layer formed by a single leveling and filling process in the prior art into multiple leveling and filling processes to form the metal mesh conductive layer 120 of this application. Each layer is made of the same material and is closely connected. Both structurally and materially, each layer can be referred to as a sub-conductive layer 121.

[0064] When different materials are present, each sub-conductive layer 121 is made of different materials and is tightly bonded to form a whole. The sub-conductive layers 121 are inseparable from each other. Structurally, the layering of different materials can be called sub-conductive layers 121.

[0065] The formation of multiple sub-conductive layers 121 in the structure depends on multiple "coating-curing" processes. Compared with the existing technology of forming a metal mesh conductive layer 120 by filling once, each independent "coating-curing" process is equivalent to reducing the thickness of the film layer generated each time. This can effectively suppress the obvious depression in the middle of the filled material after curing in the groove 1141 and improve the uniformity of the film thickness of each sub-conductive layer 121.

[0066] exist Figure 1 In the diagram, the three rectangular borders in the first substrate 110 layer represent the cross-sectional structure of the recessed region 114. The recessed region 114 includes a plurality of grooves 1141. Figure 2 A cross-sectional view of a single groove 1141 and a metal mesh conductive layer 120 within the single groove 1141 is shown. Figure 2 In the middle, the outer frame is the cross-sectional frame of the groove 1141, and the three layers of filler in the groove 1141 are the cross-section of the metal mesh conductive layer 120.

[0067] The metal mesh conductive layer 120 of this application adopts an embedded structure. The surface of the metal mesh conductive layer 120 is flush with the opening of the groove 1141, or the surface of the metal mesh conductive layer 120 is slightly lower than the opening of the groove 1141. Since the metal mesh conductive layer 120 does not protrude from the surface of the substrate 110, the surface of the substrate 110 is flat, which is conducive to the tight adhesion between the substrate 110 and the electrochromic layer 140, preventing moisture intrusion from the environment and improving the weather resistance of the electrochromic device 100.

[0068] like Figure 2 As shown, due to the presence of multiple sub-conductive layers 121, the sub-conductive layer 121 closest to the electrochromic layer 140 is approximately flush with the opening of the recessed region 114. The metal mesh conductive layer 120 formed by the stacking of each sub-conductive layer 121 can essentially fill the recessed region 114, increasing the fill factor of the recessed region 114. This is beneficial for increasing the film thickness of the metal mesh conductive layer 120, reducing the sheet resistance of the metal mesh conductive layer 120, and also making the thickness of the metal mesh conductive layer 120 uniform throughout, thus improving its conductivity.

[0069] Meanwhile, due to the increased fill factor of the groove 1141, the thickness difference between the center and the edge of the metal mesh conductive layer 120 at the groove 1141 is reduced, which reduces the stress at the connection between the metal mesh conductive layer 120 and the groove wall of the groove 1141, and reduces the risk of the metal mesh conductive layer 120 cracking at the edge of the groove 1141. This helps to reduce the risk of external environment eroding the metal mesh conductive layer 120 through cracks, thereby improving the weather resistance of the metal mesh conductive layer 120.

[0070] In some embodiments, the metal mesh conductive layer 120 includes N sub-conductive layers 121, where N is a positive integer greater than or equal to 2 and less than or equal to 10, and the thickness of the N sub-conductive layers 121 gradually decreases along the direction from the substrate 110 to the electrochromic layer 140.

[0071] In one embodiment, such as Figure 2 As shown, the number of sub-conductive layers 121 is 3. In other embodiments, the number of sub-conductive layers 121 may also be 2, 4, 5, 6, 7, 8, 9, or 10.

[0072] In one embodiment, the thickness of the N sub-conductive layers 121 gradually decreases along the direction from the substrate 110 to the electrochromic layer 140. For example, taking a metal mesh conductive layer 120 comprising three sub-conductive layers 121, the first, second, and third sub-conductive layers and the electrochromic layer 140 are arranged sequentially. Exemplarily, the depth of the recessed region 114 is set to H, the thickness of the first sub-conductive layer is 0.5H, the thickness of the second sub-conductive layer is 0.3H, and the thickness of the third sub-conductive layer is 0.2H. Of course, the thicknesses of the first to third sub-conductive layers can also be 0.6H, 0.3H, and 0.1H respectively; the specific thickness can be set according to actual needs, as long as it follows a gradually decreasing trend.

[0073] It is understandable that during the fabrication of the three sub-conductive layers 121, after curing, each sub-conductive layer 121 will exhibit varying degrees of depression in its center, and the depth of the depression is related to the thickness of that sub-conductive layer 121. After multiple "coating-curing" processes, it was observed that the greater the thickness of the cured film, the greater the depth of the depression in the center.

[0074] Therefore, after the previous sub-conductive layer 121 has cured, the next coating is applied using a paste. After coating, the coating surface is kept level, and the thickness of the coating in the middle is greater than that at the edges. In this way, after the coating has cured, most of the defects of the depression in the middle of the previous sub-conductive layer 121 can be eliminated. In this way, through multiple "coating-curing" processes, the surface of the final metal mesh conductive layer 120 near the electrochromic layer 140 becomes planar.

[0075] Furthermore, if cracks appear at the connection between the previous sub-conductive layer 121 and the wall of the recessed region 114 after the previous sub-conductive layer 121 has cured, the material applied next will flow into the cracks and fill them. Thus, through multiple "coating-curing" processes, cracking at the connection between the final metal mesh conductive layer 120 and the wall of the recessed region 114 can be effectively controlled.

[0076] In some embodiments, the conductivity of the plurality of sub-conductive layers 121 gradually decreases along the direction from the substrate 110 toward the electrochromic layer 140. Generally, the higher the conductivity of a conductive material, the more reactive the conductive material and the worse its weather resistance. In the embodiments of this application, the conductivity of the sub-conductive layer 121 closer to the electrochromic layer 140 is lower. Sub-conductive layers 121 with lower conductivity have better weather resistance, which can reduce the risk of metal ions in the sub-conductive layer 121 reacting with the electrochromic layer 140, or reduce the risk of the sub-conductive layer 121 being corroded by the electrochromic layer 140.

[0077] In some embodiments, the conductivity of the sub-conductive layer 121 is typically improved by incorporating a conductive material with high conductivity into the slurry.

[0078] In some embodiments, the conductive material is a metal, such as copper, silver, gold, nickel, aluminum, etc.

[0079] In some embodiments, the conductive material is a metal oxide, such as copper oxide, silver oxide, gold oxide, nickel oxide, etc.

[0080] In some embodiments, the conductive material incorporated into the sub-conductive layer 121 closer to the electrochromic layer 140 has higher conductivity or more conductive material incorporated.

[0081] In some embodiments, the conductive material is a carbon-based conductive material, such as graphene or carbon nanotubes.

[0082] In some embodiments, the conductive material is a composite material, such as a metal-conductive polymer, a carbon-based 110 material-metal oxide, etc.

[0083] As mentioned earlier, some conductive materials are generally quite reactive (e.g., the conductive material is a metal, metal oxide, or metal alloy), and electrochemical deposition and migration may occur in the metal mesh conductive layer 120, causing the metal mesh conductive layer 120 to react with the electrochromic material or electrolyte in the electrochromic layer 140. Alternatively, the metal mesh conductive layer 120 may be easily corroded by the electrochromic material or electrolyte in the electrochromic layer 140, affecting the performance of both the metal mesh conductive layer 120 and the electrochromic layer 140.

[0084] Based on the above, the conductivity of the multiple sub-conductive layers 121 gradually decreases along the direction from the substrate 110 to the electrochromic layer 140. This reduces the reactivity of the multiple sub-conductive layers 121 along the direction from the substrate 110 to the electrochromic layer 140. In particular, the physical and chemical reactions between the sub-conductive layers 121 closest to the electrochromic layer 140 and the electrochromic layer 140 are significantly suppressed, improving the stability of the metal mesh conductive layer 120 and the electrochromic layer 140, improving the user experience of the electrochromic device 100, and extending the service life of the electrochromic device 100.

[0085] In one embodiment, along the direction from the substrate 110 to the electrochromic layer 140, a material with high conductivity and high shrinkage is preferentially coated, followed by a material with low conductivity and low shrinkage in sequence. This results in a metal mesh conductive layer 120 with high fill rate and gradually improving weather resistance from bottom to top. In some embodiments, along the direction from the substrate 110 to the electrochromic layer 140, the density of the multiple sub-conductive layers 121 gradually increases. Density refers to the density of the sub-conductive layers; higher density means that the molecules in the sub-conductive layers 121 are closely arranged and have a high density. In this embodiment, the sub-conductive layers 121 closer to the electrochromic layer 140 have higher density, making it less likely for metal ions to precipitate from the sub-conductive layers 121 and more resistant to corrosion from the electrochromic layer 140.

[0086] It should be understood that the particle size of the conductive material in the coating slurry plays an important role in the density and conductivity of the sub-conductive layer 121.

[0087] The particle size of the conductive material is approximately 100 nm to 3000 nm. Smaller particle sizes result in better conductivity, higher density, and stronger weather resistance. Along the direction from the substrate 110 towards the electrochromic layer 140, the particle size of the conductive material in the multiple sub-conductive layers 121 gradually decreases, improving the density of the sub-conductive layers 121. This allows the metal mesh conductive layer 120 of this application to simultaneously possess excellent conductivity and weather resistance. These advantages make the electrochromic device 100 superior in terms of color-changing speed and uniformity, and also extend its service life.

[0088] The above structure forms a dense protective barrier between multiple conductive layers, making it difficult for physical and chemical reactions to occur between the sub-conductive layer 121 and the electrochromic layer 140.

[0089] The above structure is particularly suitable for forming a dense protective barrier on the side of the metal mesh conductive layer 120 near the electrochromic layer 140. Such a protective barrier has the ability to resist the influence of the electrochromic layer 140 and the influence of natural environmental factors, thereby improving the weather resistance of the metal mesh conductive layer 120.

[0090] These natural environmental factors include, but are not limited to: temperature changes: cycles from extreme low temperatures to high temperatures; humidity changes: alternations between high humidity and dry environments; ultraviolet radiation: the aging effect of ultraviolet rays in sunlight on materials; chemical substances: the effects of pollutants such as acid rain and salt spray; and mechanical stress: physical damage caused by wind, snow accumulation, etc.

[0091] In some embodiments, along the direction from the substrate 110 toward the electrochromic layer 140, the sub-conductive layer 121 near the electrochromic layer 140 is configured to prevent metal ions in the sub-conductive layer 121 near the substrate 110 from precipitating toward the electrochromic layer 140.

[0092] In some embodiments, the sub-conductive layer 121 is provided with a weather-resistant material, and the content of the weather-resistant material in the plurality of sub-conductive layers 121 gradually increases along the direction from the substrate 110 to the electrochromic layer 140.

[0093] In this process, the metal ions in the sub-conductive layer 121 near the substrate 110 are prevented from precipitating towards the electrochromic layer 140. Essentially, this is to prevent the metal ions from migrating across layers, thus preventing physical changes and chemical reactions between the two layers.

[0094] Weather-resistant materials are used to prevent physical and chemical reactions between the two layers. As weather-resistant materials are added to the sub-conductive layers 121, the weather resistance of each sub-conductive layer 121 is improved. As the content of weather-resistant materials in multiple sub-conductive layers 121 gradually increases, the mobility of metal ions gradually decreases, and the stability of each sub-conductive layer 121 gradually increases.

[0095] The aforementioned chemical reaction refers to a chemical reaction between materials. The aforementioned physical changes include, but are not limited to, cracking or bending deformation of the conductive layer 121 or the electrochromic layer 140.

[0096] In some embodiments, when a weather-resistant material is provided in the sub-conductive layer 121, the weather-resistant material is at least one of Ni (nickel), Pb (lead), Au (gold) and Pt (platinum).

[0097] Ni, Pb, Au and Pt are metals with good weather resistance. By adding them directly to the coating material, the weather resistance of the sub-conductive layer 121 can be improved.

[0098] It is particularly suitable for use when the conductive material in the coating slurry is a metal, metal oxide or metal alloy. Adding weather-resistant material can change the crystal structure and formation mode of the metal alloy, so that the weather-resistant material and the conductive material form a new alloy. The new alloy has stronger metallic bonds, thereby improving the corrosion resistance performance.

[0099] In one embodiment, each sub-conductive layer 121 is made of an AX alloy, wherein A is selected from Ag and / or Cu, and X is selected from at least one of Ni, Pb, Au, and Pt. The content of X in each sub-conductive layer 121 is different. Along the direction from the substrate 110 to the electrochromic layer 140, the content of X in each sub-conductive layer 121 gradually increases.

[0100] In one embodiment, Ag-Pb alloy particles are added to the coating slurry, wherein Ag has better conductivity than Pb, while Pb has better weather resistance than Ag. The weather resistance can be improved by increasing the proportion of Pb in the alloy particles, but the conductivity will decrease accordingly. For cases where the conductivity of the multiple sub-conductive layers 121 gradually decreases and the weather resistance of the multiple sub-conductive layers 121 gradually increases along the direction from the substrate 110 to the electrochromic layer 140, the requirements can be met by adjusting the proportion of Pb in the Ag-Pb alloy particles.

[0101] In one embodiment, Ag particles and Pb particles are added to the coating slurry, wherein the Ag particles are conductive materials and the Pb particles are weather-resistant materials. For cases where the conductivity of the multiple sub-conductive layers 121 gradually decreases and the weather resistance of the multiple sub-conductive layers 121 gradually increases along the direction from the substrate 110 to the electrochromic layer 140, the requirements can be met by adjusting the ratio of Ag particles to Pb particles.

[0102] The metal mesh conductive layer 120 formed through the above embodiments exhibits both good conductivity and weather resistance. These advantages make the electrochromic device 100 superior in terms of color-changing speed and uniformity, and also extend its service life.

[0103] In some embodiments, the recessed region 114 includes a plurality of intersecting grooves 1141, which form a mesh structure. A conductive strip is formed in each groove 1141, and the plurality of conductive strips constitute a metal mesh conductive layer 120.

[0104] The width of the groove 1141 is 5μm-20μm. Specifically, the width of the groove 1141 can be 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, 11μm, 12μm, 13μm, 14μm, 15μm, 16μm, 17μm, 18μm, 19μm or 20μm, etc., and is not limited to the width in the example.

[0105] The depth of groove 1141 is 5μm-20μm. Specifically, the depth of groove 1141 can be 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, 11μm, 12μm, 13μm, 14μm, 15μm, 16μm, 17μm, 18μm, 19μm or 20μm, etc., and is not limited to the width in the example.

[0106] The depth and width of the recessed region 114 are related to the thickness and width of each conductive strip in the metal mesh conductive layer 120.

[0107] By increasing the depth of the groove 1141, the conductive strip can be made thicker, improving its current carrying capacity and increasing its conductivity.

[0108] The spacing between the two parallel conductive strips ranges from 5μm to 500μm. By setting the width of the groove 1141 within a suitable range, it is beneficial to balance the conductivity and insulation of the conductive strips, thereby maximizing the benefits.

[0109] In one embodiment, the depth / width ratio of the groove 1141 is 1, 1.5, or 2, etc. Increasing the thickness of the conductive strip improves its conductivity and also reduces the adverse effects caused by widening the groove 1141.

[0110] In some embodiments, such as Figure 1 As shown, the electrochromic device 100 also includes a protective layer 130.

[0111] The protective layer 130 is mainly used to hinder the reaction between the sub-conductive layer 121 and the electrochromic layer 140, reduce the ion migration of conductive materials under the influence of voltage, light, heat and other conditions, and prevent the metal mesh conductive layer 120 from being scratched, increase the toughness of the film material, and prevent the metal material from cracking during bending and processing.

[0112] A protective layer 130 is disposed on the surface of the substrate 110 and covers the recessed area 114. An electrochromic layer 140 is disposed on the side of the protective layer 130 away from the metal mesh conductive layer 120, so that the side of the metal mesh conductive layer 120 and the electrochromic layer 140 that are close to each other are completely separated by the protective layer 130, thereby improving the structural stability of the electrochromic device 100.

[0113] The protective layer 130 is electrically connected to the metal mesh conductive layer 120. Thus, when the metal mesh conductive layer 120 is energized, the current is transmitted through the protective layer 130 to the electrochromic layer 140, changing the optical state of the electrochromic layer 140, so that the device having the electrochromic device 100 exhibits reversible changes in color and transparency in appearance.

[0114] In one embodiment, the conductivity of the metal mesh conductive layer 120 is higher than that of the protective layer 130. In this embodiment, the high conductivity of the metal mesh conductive layer 120 is beneficial for improving the color-changing rate of the electrochromic device 100. Simultaneously, the addition of the protective layer 130 between the electrochromic layer 140 and the metal mesh conductive layer 120 reduces the reaction between them, lowering the risk of corrosion of the metal mesh conductive layer 120.

[0115] In some embodiments, the conductivity of the metal mesh conductive layer 120 ranges from (5-100) x 10^6 S / m, and its sheet resistance is 0.1 Ω / sq to 100 Ω / sq. The sheet resistance of the protective layer 130 is 20 Ω / sq to 500 Ω / sq. Sheet resistance, also known as sheet resistance, is measured in Ω / sq, which refers to ohms per square.

[0116] In some embodiments, the protective layer 130 is configured to prevent chemical reactions with the metal mesh conductive layer 120.

[0117] In one embodiment, the protective layer 130 is configured to prevent metal ions in the metal mesh conductive layer 120 from depositing into the protective layer 130. This also prevents metal ions in the metal mesh conductive layer 120 from depositing into the electrochromic layer 140, improving the weather resistance of the electrochromic device 100 and making the structure of the electrochromic device 100 more stable.

[0118] In some embodiments, such as Figure 1 As shown, the protective layer 130 includes at least one sub-protective layer 130, which is a transparent and conductive sub-protective layer 130, so that the color light emitted by the electrochromic layer 140 is transmitted through the protective layer 130 to the substrate 110, making it easy to see the color change generated on the electrochromic layer 140 visually.

[0119] In some embodiments, the protective layer 130 includes M sub-protective layers 130, where M is a positive integer not exceeding 4.

[0120] Specifically, the number of sub-protective layers 130 is 1, 2, 3 or 4.

[0121] The protective layer 130 is made by multiple coatings or platings, and is the same as the metal mesh conductive layer 120. Structurally, the protective layer 130 can be divided into multiple sub-protective layers 130, and the materials of each sub-protective layer 130 can be the same or different.

[0122] In one embodiment, such as Figure 1 As shown, the protective layer 130 includes at least one of a first sub-protective layer 131 and a second sub-protective layer 132.

[0123] The first sub-protective layer 131 is formed by a coating process, and the material of the first sub-protective layer 131 includes, but is not limited to, any one of ITO (indium tin oxide), AZO (zinc aluminum oxide), and ZnO (zinc oxide). The second sub-protective layer 132 is formed by coating.

[0124] In some embodiments, the thickness of the first sub-protective layer 131 is 100–200 nm.

[0125] Specifically, the thickness of the first sub-protective layer 131 is 100nm, 110nm, 120nm, 130nm, 140nm, 150nm, 160nm, 170nm, 180nm, 190nm or 200nm, etc., and is not limited to the thickness in the example.

[0126] The second protective layer 132 can be a coating layer, and the material of the second protective layer 132 includes, but is not limited to, any one of PEDOT:PSS (poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid)), P3HT (poly(3-hexylthiophene)), PDDT (polyhydroquinone terephthalate), PPV (poly(p-styrene)), graphene, and carbon nanotubes.

[0127] In some embodiments, the thickness of the second sub-protective layer 132 is 500–2000 nm.

[0128] Specifically, the thickness of the second sub-protective layer 132 is 500nm, 550nm, 600nm, 650nm, 700nm, 750nm, 800nm, 850nm, 900nm, 950nm, 1000nm, 1050nm, 1100nm, 1150nm, 1200nm, 1250nm, 1300nm, 1350nm, 1400nm, 1450nm, 1500nm, 1550nm, 1600nm, 1650nm, 1700nm, 1750nm, 1800nm, 1850nm, 1900nm, 1950nm, or 000nm, etc., and is not limited to the thickness in the example.

[0129] In some embodiments, the substrate 110, the first sub-protective layer 131, the second sub-protective layer 132 and the electrochromic layer 140 are stacked sequentially.

[0130] In some embodiments, such as Figure 1 As shown, the substrate 110 includes a first base layer 111, a second base layer 112 and a third base layer 113 stacked sequentially.

[0131] The third substrate 113 includes at least one of a glass substrate and PET, and the third substrate 113 formed by the PET material and the glass substrate is a transparent film layer that can transmit light.

[0132] The second base layer 112 includes at least one of a hardening layer, an anti-reflection layer, a heat insulation layer, and a heating layer.

[0133] The second base layer 112 is mainly made of acrylic resin and organosilicon polymers, and the second base layer 112 is a transparent film layer that can transmit light.

[0134] In one embodiment, a hardening layer or an anti-reflection layer is coated on the surface of the second substrate layer 112. The hardening layer and the anti-reflection layer are used to adjust the optical properties of the substrate 110. The hardening layer and the anti-reflection layer are 0.5 μm to 5 μm in diameter, respectively.

[0135] In one embodiment, SiO2 particles, ZrO2, TiO2, and ZnO particles are added to the polymer used to fabricate the second substrate layer 112 to achieve anti-reflection and anti-reflection effects, thereby adjusting the optical properties of the substrate 110.

[0136] The thickness of the second substrate layer 112 can adjust the optical properties of the substrate 110, such as reflective color and transmittance.

[0137] In one embodiment, when the application scenario of the electrochromic device 100 does not have special requirements for reflective color and transmittance, the second substrate layer 112 can be omitted.

[0138] In one embodiment, the second base layer 112 can be omitted when the thickness of the first base layer 111 meets the optical requirements.

[0139] The second base layer 112 and the third base layer 113 serve a load-bearing function, and the reflected light can be adjusted by the thickness of the second base layer 112.

[0140] The thickness of the first substrate layer 111 is 3μm-15μm, which facilitates the formation of a recessed region 114 on the surface of the first substrate layer 111 away from the second substrate layer 112, and the metal mesh conductive layer 120 is disposed on the surface of the first substrate layer 111.

[0141] The first base layer 111 includes a resin, making the first base layer 111 a transparent film layer that is transparent to light.

[0142] In some embodiments, the electrochromic device 100 includes two substrates 110 and two metal mesh conductive layers 120. The two metal mesh conductive layers 120 are respectively disposed in the recessed regions 114 of the two substrates 110. The electrochromic layer 140 is arranged between the two metal mesh conductive layers 120, and the two surfaces of the electrochromic layer 140 arranged opposite to each other are electrically connected to the two metal mesh conductive layers 120.

[0143] In one embodiment, such as Figure 1 As shown, the electrochromic device 100 of this application includes a substrate 110, a protective layer 130, an electrochromic layer 140, another protective layer 130, and another substrate 110 stacked sequentially. A metal mesh conductive layer 120 is embedded in one substrate 110 near the electrochromic layer 140, and another metal mesh conductive layer 120 is embedded in the other substrate 110 near the electrochromic layer 140.

[0144] It can be understood that the electrochromic layer 140 generally includes an electrochromic material layer 141 (EC), an electrolyte layer 142 (Ely), and an ion storage layer 143 (IS) stacked sequentially. The electrochromic material layer 141 includes an electrochromic material, and the ion storage material in the ion storage layer 143 is mainly used to store ions. When an electric current is applied, ions from the ion storage material transfer to the electrochromic layer, and the electrochromic layer absorbs these ions and changes color. The electrolyte layer 142, also known as the ion transfer layer, is the ion transfer channel.

[0145] The working principle of the electrochromic device 100 of this application is as follows:

[0146] One of the metal mesh conductive layers 120 is electrically contacted with an external terminal (not shown) via a first busbar (not shown) thereon, and another metal mesh conductive layer 120 is electrically contacted with another external terminal (not shown) via a second busbar thereon. Thus, by connecting a power source to the two external terminals, a voltage can be applied between the two metal mesh conductive layers 120, thereby changing the transmittance of the electrochromic device 100.

[0147] Voltage causes ions to move between the electrochromic material layer 141 and the ion storage layer 143, and to insert / extract or extract / insert between the electrochromic material layer 141 and the ion storage layer 143, thereby changing the optical state of the electrochromic material in the electrochromic material layer 141, and thus changing the transmittance of the electrochromic device 100, adjusting it between the colored state, intermediate state and transparent state.

[0148] like Figure 3 As shown in the embodiment of this application, a method for manufacturing an electrochromic device 100 is also provided, including:

[0149] Step S1: Provide a substrate 110 and form a grid-like recessed area 114 on one surface of the substrate 110.

[0150] In some embodiments, a substrate 110 is provided, and a grid-like recessed area 114 is formed on the surface of the substrate 110 by imprinting. The fabrication of the recessed area 114 may also include electrohydraulic printing, inkjet printing, screen printing, photolithography, or fission method, wherein the fission method refers to the method of rapidly drying the film after coating to cause the film to crack and form cracks, and the formed cracks are the recessed areas 114.

[0151] Step S2: Sub-conductive layers 121 are sequentially fabricated from the inside to the outside in the recessed region 114 to form a metal mesh conductive layer 120 with multiple sub-conductive layers 121.

[0152] In some embodiments, a first coating is applied to the bottom of the recessed area 114. After the first coating material has cured, a second coating is applied to the surface of the cured material. After the second coating material has cured, a third coating is applied to the surface of the cured material. This process is repeated multiple times until the recessed area 114 is filled. The surface of the material after the last curing is approximately flush with the opening of the recessed area 114, and the metal mesh conductive layer 120 is completed.

[0153] The curing methods include thermal curing and photocuring.

[0154] Step S3: Fabricate a protective layer 130 between the metal mesh conductive layer 120 and the substrate 110.

[0155] In some embodiments, a protective layer 130 is formed on the surface of the substrate 110 and the metal mesh conductive layer 120 by methods such as magnetron sputtering, vacuum evaporation, screen printing, coating, and electrochemical polymerization.

[0156] Step S4: Fabricate an electrochromic layer 140 on the protective layer 130.

[0157] In some embodiments, an electrochromic layer 140 is formed on the protective layer 130 by means of scraping or the like.

[0158] Step S5: Create another protective layer 130 on the electrochromic layer 140.

[0159] In some embodiments, another protective layer 130 is formed on the surface of the electrochromic layer 140 by methods such as magnetron sputtering, vacuum evaporation, screen printing, coating, and electrochemical polymerization.

[0160] Step S6: Provide another substrate 110, form a grid-shaped recessed area 114 on one surface of the substrate 110, and fabricate a metal grid conductive layer 120 in the recessed area 114.

[0161] In some embodiments, a substrate 110 is provided, and a grid-like recessed area 114 is formed on the surface of the substrate 110 by imprinting. The fabrication of the recessed area 114 may also include electrohydraulic printing, inkjet printing, screen printing, photolithography, or fission method, wherein the fission method refers to the method of rapidly drying the film after coating to cause the film to crack and form cracks, and the formed cracks are the recessed areas 114.

[0162] In some embodiments, a first coating is applied to the bottom of the recessed area 114. After the first coating material has cured, a second coating is applied to the surface of the cured material. After the second coating material has cured, a third coating is applied to the surface of the cured material. This process is repeated multiple times until the recessed area 114 is filled. The surface of the material after the last curing is approximately flush with the opening of the recessed area 114, and the metal mesh conductive layer 120 is completed.

[0163] The curing methods include thermal curing and photocuring.

[0164] Step S7: Combine the other substrate 110 from step S6 with the protective layer 130 from step S5 to form an electrochromic device.

[0165] It should be noted that the order of steps S1 to S7 can be adjusted.

[0166] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0167] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. An electrochromic device, characterized in that, include: The substrate has recessed areas formed on its surface; A metal mesh conductive layer is disposed within the recessed area and does not protrude from the surface of the substrate; An electrochromic layer is disposed on the side of the metal mesh conductive layer away from the substrate and is electrically connected to the metal mesh conductive layer; The metal mesh conductive layer comprises multiple sub-conductive layers stacked sequentially.

2. The electrochromic device according to claim 1, characterized in that, The metal mesh comprises N sub-conductive layers, where N is a positive integer greater than or equal to 2 and less than or equal to 10. The thickness of the N sub-conductive layers gradually decreases along the direction from the substrate to the electrochromic layer.

3. The electrochromic device according to claim 1, characterized in that, Along the direction from the substrate to the electrochromic layer, the conductivity of the plurality of sub-conductive layers gradually decreases.

4. The electrochromic device according to claim 1, characterized in that, Along the direction from the substrate to the electrochromic layer, the density of the plurality of sub-conductive layers gradually increases.

5. The electrochromic device according to any one of claims 2 to 4, characterized in that, Along the direction from the substrate to the electrochromic layer, the sub-conductive layer near the electrochromic layer is configured to prevent metal ions in the sub-conductive layer near the substrate from depositing towards the electrochromic layer; and / or The sub-conductive layer contains a weather-resistant material, and the content of the weather-resistant material in the plurality of sub-conductive layers gradually increases along the direction from the substrate to the electrochromic layer.

6. The electrochromic device according to claim 5, characterized in that, When the sub-conductive layer contains a weather-resistant material, the weather-resistant material is at least one of Ni, Pb, Au, and Pt.

7. The electrochromic device according to any one of claims 2 to 4, characterized in that, The recessed area includes multiple intersecting grooves, the width of which is 5μm-20μm and the depth of which is 5μm-20μm.

8. The electrochromic device according to claim 1, characterized in that, The electrochromic device further includes a protective layer configured to prevent chemical reaction with the metal mesh conductive layer. The protective layer is disposed on the surface of the substrate near the electrochromic layer and covers the recessed area. The protective layer is electrically connected to the metal mesh conductive layer.

9. The electrochromic device according to claim 8, characterized in that, The conductivity of the metal mesh conductive layer is greater than that of the protective layer.

10. The electrochromic device according to claim 9, characterized in that, The protective layer includes a first sub-protective layer and a second sub-protective layer. The first sub-protective layer includes any one of ITO, AZO, and ZnO, and the second sub-protective layer includes any one of PEDOT:PSS, P3HT, PDDT, PPV, graphene, and carbon nanotubes.

11. The electrochromic device according to any one of claims 2 to 4, characterized in that, The substrate comprises a first base layer, a second base layer, and a third base layer stacked sequentially, wherein: The recessed region is formed on the surface of the first substrate layer away from the second substrate layer, and the metal mesh conductive layer is disposed on the surface of the first substrate layer. The first substrate layer includes resin. The second substrate layer includes at least one of a hardening layer, an anti-reflection layer, a heat insulation layer, and a heating layer; the third substrate layer includes at least one of a glass substrate and PET.

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