Electrochromic device

Abstract

The present invention relates to an electrochromic device (1) comprising a first electrochromic material layer (10); a second transparent electrochromic material layer (11) positioned above the first layer (10); and an electrolyte layer (12) disposed between the first electrochromic material layer (10) and the second electrochromic material layer (11). The electrochromic device is characterized in that the electrochromic device comprises at least one first conductive layer (13a) in contact with the second electrochromic material layer (11), the second electrochromic material layer (11) forming an electrode of the electrochromic device (1), and the first conductive layer (13a) forming a current collector of the device (1) that is only in electrical contact with the second electrochromic material layer (11).

Description

Technical Field

[0001] This invention relates to the technical field of electrochromic devices. Background Technology

[0002] Electrochromic devices, similar to optical cells, are electrical devices capable of modulating their optical properties when an electric field is applied, thus allowing for easy adjustment of color changes or light transmission capabilities. Therefore, electrochromic devices can be used in applications such as those requiring modulation of desired light transmission for aesthetic reasons, light control, or energy efficiency. Examples include electrochromic windows in residential windows, particularly for adjusting sunlight levels in a room based on external conditions and user preferences, or as windshields and / or side windows or roof windows in automobiles to adjust transparency levels, and especially to regulate light transmitted to the driver to avoid potential glare. Electrochromic devices are also found in applications such as electrochromic mirrors, visual display units, or data displays.

[0003] However, electrochromic devices already in use typically tend to have rather slow switching speeds, meaning that the color change is not as fast and optimal as expected for applications of this type of product.

[0004] Therefore, in this context, the present invention seeks to overcome all the aforementioned drawbacks. Thus, the object of the present invention is to provide an electrochromic device that improves the speed of color change. Summary of the Invention

[0005] The present invention aims to provide an electrochromic device comprising a first electrochromic material layer; a second transparent electrochromic material layer positioned above the first layer; and an electrolyte layer disposed between the first and second electrochromic material layers. A significant feature of the electrochromic device is that it includes at least one first conductive layer in contact with the second electrochromic material layer, the second electrochromic material layer forming an electrode of the electrochromic device, and the first conductive layer forming a current collector of the device that is only in electrical contact with the second electrochromic material layer.

[0006] In the context of this invention, the term "layer" means a more or less uniform extension of material with a thickness relatively small relative to its surface area. As a non-limiting example, it is conceivable that each layer is produced during the same step of a method for manufacturing a device according to the invention, or that several layers, particularly formed of the same material or a combination of the same materials, are produced simultaneously during the same step of a method for manufacturing a device according to the invention.

[0007] In the context of this invention, the term "electrochromic material" refers to a material or combination of materials capable of reversibly changing its color and / or transparency in response to a charge applied to the material or combination of materials. Preferably, when a voltage is applied between the electrodes of the device, a change in color and / or transparency can occur, thereby causing ions to migrate through the electrolyte layer to react with the electrochromic material according to a redox reaction.

[0008] The first electrochromic material layer may be adapted to conduct electric current. The first electrochromic material layer may include electrodes. The second electrochromic material layer is adapted to include conductive charges. The second layer may include electrodes. The first electrochromic material layer may contain a material different from the material of the second electrochromic material layer. The second electrochromic material layer is transparent.

[0009] The second electrochromic material layer can increase the speed of color and / or transparency changes. This layer can be a transparent electrode or a color-changing material.

[0010] Therefore, electrochromic devices can change color or transparency under the influence of a voltage applied between electrodes. This change in color or transparency can be achieved through electrochemical reactions within the electrochromic material. It is precisely because electrochromic materials can undergo reversible changes in color or transparency in response to electrical stimulation that they are effective.

[0011] The conductive layer allows voltage to be applied between the electrodes of the device. An electric field can be generated across the electrolyte, resulting in reversible or irreversible changes in color or transparency, thus producing an electrochromic effect.

[0012] In this system, the electrolyte allows ion migration, thus improving the performance of the electrochromic device. The electrolyte may include a substance capable of generating ions that are conductive and move under the influence of an electric field.

[0013] A current collector can be a component of an electrochromic device, used to collect current from different sources or elements and direct that current to a specific destination. The current collector does not directly accept any charge of the same kind as the electrolyte layer. The current collector layer can be a carbon layer. The carbon layer can be opaque. The carbon layer can be used to conduct current.

[0014] In the context of the electrochromic device of the present invention, the term carbon is intended to refer to the opaque layer and its conductivity is about ten times that of the electrochromic layer, rather than to a chemical element.

[0015] The first conductive layer may contain at least one carbon element, such as carbon fiber.

[0016] The first conductive layer may consist essentially of at least one carbon element (e.g., carbon fiber).

[0017] The presence of carbon in the first conductive layer provides excellent conductivity, which improves the efficiency of electron transport in electrochromic devices.

[0018] The second electrochromic layer may contain a transparent polymer.

[0019] The presence of transparent polymers allows for excellent light transmission in the faded state of the device, which enables better visualization of changes in the color state.

[0020] The second electrochromic layer may be composed of a transparent or translucent polymer.

[0021] Advantageously, the first conductive layer and the second electrochromic material layer are separate.

[0022] Advantageously, the electrolyte layer is transparent.

[0023] The use of a transparent electrolyte layer helps achieve better light transmission through the electrochromic device, and thus maintains better transparency in the faded state of the electrochromic device. The transparency of the electrolyte layer can also be used to maximize the contrast between the colored and faded states of the device.

[0024] Advantageously, the second electrochromic material layer is in complete contact with the electrolyte layer.

[0025] Advantageously, the electrochromic device includes a second conductive layer in contact with a first electrochromic material layer, the first electrochromic material layer forming an electrode of the electrochromic device.

[0026] The second conductive layer is not in physical contact with the first conductive layer.

[0027] In one embodiment, the second conductive layer may contain carbon.

[0028] In one specific embodiment, the first conductive layer and / or the second conductive layer may comprise a metal.

[0029] Each of the first and second electrochromic material layers may include an electrode. One of the electrochromic material layers may include a cathode electrode, and the other electrochromic material layer may include an anode counter electrode.

[0030] Advantageously, the electrochromic device includes a barrier layer disposed between a first electrochromic layer and a second electrochromic layer and capable of preventing ions from migrating into the electrolyte layer. The barrier layer defines at least one channel through which ions of the electrolyte layer can flow freely.

[0031] The barrier layer may comprise a dielectric material. The barrier layer may include an outer contour that defines a pattern. The barrier layer may include an inner contour defined by at least one channel. The inner contour defines a pattern. Therefore, a pattern can be generated using an electrochromic device by alternating between channels that allow free circulation of ions and portions of the barrier layer that prevent said ion circulation.

[0032] Therefore, it is the barrier layer that allows the display of patterns that are invisible when the electrochromic device is in a passive state and become visible when the electrochromic device is activated by a potential difference.

[0033] Advantageously, the first and second electrochromic layers cover the entire channel formed by the barrier layer.

[0034] This complete coverage ensures uniform coloration across the entire active surface of the device, thus avoiding uncolored or irregular areas that could affect optical performance. Complete coverage also allows for optimal interaction between the electrochromic layer and the barrier layer, thereby promoting more efficient transfer of ions and electrons across the common surface.

[0035] Advantageously, the second electrochromic layer and electrolyte layer of the electrochromic device do not contain inorganic materials.

[0036] In one implementation, the barrier layer may not contain inorganic materials.

[0037] Advantageously, the first electrochromic layer and / or the second electrochromic layer contain a conductive material.

[0038] In one embodiment, the conductive material may include PEDOT:PSS.

[0039] Advantageously, the electrolyte layer contains a polymer suitable for UV crosslinking.

[0040] In one embodiment, the electrolyte layer comprises at least one ionic liquid. In another embodiment, the electrolyte layer may lack an ionic liquid.

[0041] In one embodiment, the electrolyte layer may contain dissolved salts.

[0042] Advantageously, the electrochromic device includes at least a first encapsulation layer arranged to cover the device.

[0043] In one embodiment, which includes a support layer comprising a plastic substrate, the electrochromic device may comprise only a first encapsulation layer. The substrate may be used to support the electrochromic device.

[0044] In embodiments that include a support layer containing a plastic-free substrate, the electrochromic device may include a first encapsulation layer and a second encapsulation layer, the second encapsulation layer being mounted between the support layer and the first electrochromic material layer.

[0045] A further object of the present invention is a method for manufacturing an electrochromic device as previously described. The method is significant in that it includes the following steps: depositing an electrochromic material to form a first electrochromic layer; depositing an electrolyte material on the first electrochromic layer to form an electrolyte layer; depositing an electrochromic material on the electrolyte layer to form a second electrochromic layer; depositing a conductive material on only a portion of the second electrochromic layer to form a first conductive layer; and depositing a conductive material on a portion of the first electrochromic layer to form a second conductive layer.

[0046] In methods used to manufacture electrochromic devices, deposition means, for example, depositing a layer by printing.

[0047] The second encapsulation layer may be adapted to cover at least a portion of the substrate. In another embodiment, the second layer may completely cover the substrate.

[0048] The electrochromic material forming the first electrochromic material layer can be deposited on only a portion of the second encapsulation layer.

[0049] The electrolyte material can be arranged to completely or partially cover the barrier layer and overlap a portion of the electrochromic layer at an opening in the barrier layer.

[0050] The second electrochromic layer can be arranged to cover the electrolyte layer.

[0051] The conductive material of the first conductive layer disposed on only a portion of the second electrochromic layer may also cover a portion of the substrate. In embodiments including a second encapsulation layer, the conductive material of the first conductive layer may cover a portion of the second encapsulation layer.

[0052] The second conductive layer may overlap a portion of the second electrochromic layer and a portion of the substrate. In another embodiment including a second encapsulation layer, the second conductive layer may cover a portion of the second encapsulation layer.

[0053] In one embodiment, the electrochromic device may include a support layer, which may include a substrate. In one embodiment, the substrate may be flexible. In one embodiment, the substrate may include paper.

[0054] Advantageously, the electrochromic device includes a substantially flexible support layer on which a first electrochromic material layer is positioned.

[0055] The support layer can be a dielectric material. In another embodiment, the support layer can be paper.

[0056] Advantageously, the manufacturing method includes the following steps: depositing encapsulation material to form a second encapsulation layer; depositing dielectric material to form a barrier layer; and depositing encapsulation material to form a first encapsulation layer.

[0057] The dielectric material forming the barrier layer can be arranged to overlap with a portion of the first electrochromic layer and a portion of the second encapsulation layer.

[0058] The first encapsulation layer may be adapted to cover at least a portion of the electrochromic device. In another embodiment, the first encapsulation layer may be adapted to completely cover the electrochromic device.

[0059] Advantageously, in the manufacturing method, the first conductive layer and the second conductive layer are deposited simultaneously.

[0060] The first conductive layer and the second conductive layer are separated from each other, meaning they do not contact each other but are printed simultaneously.

[0061] Therefore, a user viewing the electrochromic device observes it from the surface toward the substrate supporting the electrochromic device. The layer closest to the user is the first encapsulation layer (15), followed by the second electrochromic material layer (11), and then the electrolyte (12), which completely covers the barrier layer (14) mounted on the first electrochromic material layer (10). The assembly may cover the second encapsulation layer (16), which itself is mounted on the substrate (17). In this assembly, the first conductive layer (also called the current collector) is in contact with the first electrochromic material layer, and the second conductive layer is in contact with the second electrochromic material layer.

[0062] Due to the transparency of the second electrochromic material layer, the user can observe the electrolyte layer underneath. Therefore, the color change of the electrolyte can be observed. Attached Figure Description

[0063] Further advantages and features of the invention will now be described with the aid of examples and accompanying drawings, which are merely illustrative and in no way limit the scope of the invention. The accompanying drawings illustrate: [ Figure 1 A schematic cross-sectional view of an electrochromic device is shown, illustrating the extension of the layer in a direction transverse to the viewing direction of the display.

[0064] In the following description, unless otherwise stated, elements that are structurally or functionally identical in different figures retain the same reference numerals. Detailed Implementation

[0065] A schematic cross-sectional view of an electrochromic device 1 according to one embodiment is shown in [ Figure 1 ]middle.

[0066] The flexible substrate 17 is used to manufacture [ Figure 1 The electrochromic device 1 described in the document. The substrate 17 includes paper. The substrate 17 supports the electrochromic device 1.

[0067] Encapsulation material is deposited on substrate 17 to form a second encapsulation layer 16. The encapsulation material is deposited by printing.

[0068] An electrochromic material is deposited on the second encapsulation layer 16 to form a first electrochromic layer 10. The electrochromic material is deposited by printing. The first electrochromic material layer 10 covers only a portion of the second encapsulation layer 16. The first electrochromic layer 10 contains a conductive material and is adapted to conduct current. The first electrochromic layer 10 includes PEDOT:PSS.

[0069] A dielectric material is deposited to form a barrier layer 14. The dielectric material is deposited by printing. The barrier layer covers a portion of the first electrochromic layer 10 and a portion of the second encapsulation layer 16. The barrier layer is disposed between the first electrochromic layer 10 and the second electrochromic layer 11. The barrier layer 14 prevents ions from migrating into the electrolyte layer 12. The barrier layer 14 defines at least one channel through which ions from the electrolyte layer 12 can flow freely. The barrier layer 14 includes an outer contour defining a pattern. The barrier layer 14 includes an inner contour defined by at least one channel. The inner contour defines the pattern. Thus, by alternating between channels that allow ions to circulate freely and portions of the barrier layer 14 that prevent the ions from circulating, a pattern can be generated using the electrochromic device 1. Thus, it is the barrier layer 14 that allows the display of a pattern that is invisible when the electrochromic device 1 is in a passive state and becomes visible when the electrochromic device 1 is in an active state. The barrier layer 14 lacks inorganic material.

[0070] An electrolyte material is deposited to form an electrolyte layer 12. The electrolyte material is deposited by printing. The electrolyte layer 12 is arranged to cover a barrier layer 14 and overlaps a portion of the first electrochromic layer 10 at an opening in the barrier layer 14. The electrolyte material includes a substance that generates ions capable of conducting electricity and moving under the influence of an electric current. The electrolyte layer 12 contains a polymer suitable for UV crosslinking.

[0071] An electrochromic material is deposited to form a second electrochromic material layer 11. The electrochromic material is deposited by printing. The second electrochromic material layer 11 is adapted to include conductive charges. The second electrochromic layer 11 includes electrodes. The second electrochromic layer 11 includes transparent electrodes. The second electrochromic layer 11 contains conductive material and is adapted to conduct current. The second electrochromic layer 11 contains a conductive polymer.

[0072] A conductive material is deposited to form a first conductive layer 13a. The first conductive layer 13a is arranged to cover only a portion of the second electrochromic layer 11. The first conductive layer 13a is arranged to cover a portion of the second encapsulation layer 16. The first conductive layer 13a contains carbon.

[0073] A conductive material is deposited to form a second conductive layer 13b. The second conductive layer 13b is arranged to cover a portion of the first electrochromic material layer 10, which is not covered by the barrier layer 14 and the electrolyte layer 12. The second conductive layer 13b covers a portion of the second encapsulation layer 16. The second conductive layer 13b is not in physical contact with the first conductive layer 13a. The second conductive layer 13b contains carbon.

[0074] The conductive material forming the first conductive layer 13a and the conductive material forming the second conductive layer 13b are deposited simultaneously by printing. The first conductive layer 13a and the second conductive layer 13b are physically separated from each other, so they do not contact each other, but are printed simultaneously in the method for manufacturing the electrochromic device 1.

[0075] Depositing encapsulation material to form a first encapsulation layer 15. The first encapsulation layer 15 is arranged to cover at least a portion of the electrochromic device 1.

[0076] The foregoing description clearly explains how the present invention achieves its objective of providing an electrochromic device for improving the speed of color change by providing an electrochromic device comprising: a first electrochromic material layer; a second transparent electrochromic material layer positioned above the first layer; an electrolyte layer disposed between the first and second electrochromic material layers, and the electrochromic device comprising at least one first conductive layer in contact with the second electrochromic material layer, the second electrochromic material layer forming an electrode of the electrochromic device, and the first conductive layer forming a current collector of the device that is in electrical contact only with the second electrochromic material layer.

[0077] In no event is the invention limited to the embodiments specifically described herein, but particularly extends to any equivalent means and any combination of technical operations of such means. In particular, one may contemplate: - A support layer for electrochromic devices, including a substrate containing dielectric materials; - Includes a support layer for a plastic substrate; in this embodiment, the electrochromic device includes only a first encapsulation layer. - The second conductive layer 13b may overlap with a portion of the second electrochromic layer 11 and a portion of the substrate 17; - Electrolyte layer 12 may lack ionic liquid; - Electrolyte layer 12 may contain dissolved salts; - The first electrochromic material layer 10 and the second electrochromic material layer 11 may contain different materials; - The second electrochromic layer 11 contains a material that can change color; - The first conductive layer 13a may contain metal; - The second conductive layer 13b may contain metal.

Claims

1. An electrochromic device (1), the electrochromic device comprising: -First electrochromic material layer (10); - A second transparent electrochromic material layer (11) is positioned above the first layer (10); - Electrolyte layer (12), the electrolyte layer being disposed between the first electrochromic material layer (10) and the second electrochromic material layer (11); The electrochromic device is characterized in that it includes at least one first conductive layer (13a), which is in contact with the second electrochromic material layer (11), the second electrochromic material layer (11) forming the electrode of the electrochromic device (1), and the first conductive layer (13a) forming the current collector of the device (1) which is in electrical contact only with the second electrochromic material layer (11).

2. The electrochromic device (1) according to claim 1, characterized in that, The first conductive layer (13a) and the second electrochromic material layer (11) are separate.

3. The electrochromic device (1) according to any one of the preceding claims, characterized in that, The second electrochromic material layer (11) is in complete contact with the electrolyte layer (12).

4. The electrochromic device (1) according to any one of the preceding claims, characterized in that, The electrochromic device includes a second conductive layer (13b) that is in contact with the first electrochromic material layer (10), and the first electrochromic material layer (10) forms the electrode of the electrochromic device (1).

5. The electrochromic device (1) according to any one of the preceding claims, characterized in that, The electrochromic device includes a barrier layer (14) disposed between the first electrochromic layer (10) and the second electrochromic layer (11) and capable of preventing ions from migrating into the electrolyte layer (12). The barrier layer (14) defines at least one channel through which ions of the electrolyte layer (12) can flow freely.

6. The electrochromic device (1) according to claim 5, characterized in that, The first electrochromic layer (10) and the second electrochromic layer (11) cover the entire channel formed by the barrier layer (14).

7. The electrochromic device (1) according to any one of the preceding claims, characterized in that, The first electrochromic layer (10) and / or the second electrochromic layer (11) contain conductive materials.

8. The electrochromic device (1) according to any one of the preceding claims, characterized in that, The electrolyte layer (12) contains a polymer suitable for UV crosslinking.

9. The electrochromic device (1) according to any one of the preceding claims, characterized in that, The electrochromic device includes at least a first encapsulation layer (15) arranged to cover the device (1).

10. A method for manufacturing an electrochromic device (1) according to any one of the preceding claims, characterized in that, The method includes the following steps: -Deposit electrochromic material to form the first electrochromic layer (10). - An electrolyte material is deposited on the first electrochromic layer (10) to form the electrolyte layer (12). - An electrochromic material is deposited on the electrolyte layer (12) to form the second electrochromic layer (11). - A conductive material is deposited on only a portion of the second electrochromic layer (11) to form the first conductive layer (13a). - A conductive material is deposited on a portion of the first electrochromic layer (10) to form the second conductive layer (13b).

11. The manufacturing method according to the preceding claim, characterized in that, The manufacturing method includes the following steps: -Deposit encapsulation material to form a second encapsulation layer (16). -Deposit dielectric material to form the barrier layer (14). - Deposit encapsulation material to form the first encapsulation layer (15).

12. The manufacturing method according to the preceding claim, characterized in that, The first conductive layer (13a) and the second conductive layer (13b) are deposited simultaneously.

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