An electrochromic device with high low-temperature resistance

Abstract

The application relates to a high and low temperature resistant electrochromic device. The high and low temperature resistant electrochromic device comprises a first transparent electrode, an electrochromic layer, a composite gel electrolyte layer and a second transparent electrode which are sequentially stacked; the composite gel electrolyte layer is obtained by coating and curing a mixed solution obtained by mixing a alginate solution and a resin slurry containing cations.

Description

Technical Field

[0001] This invention relates to an electrochromic device with strong high and low temperature resistance, belonging to the field of chemical material synthesis and functional material technology. Background Technology

[0002] Energy is a crucial foundation for maintaining a nation's sustained economic development and ensuring people's material well-being. Today, energy shortages and environmental pollution are increasingly severe, prompting scientists to develop new energy sources while simultaneously seeking methods to conserve energy and reduce consumption. Electrochromic devices and technologies are primarily applied in energy-efficient building glass, vehicle windows, anti-glare rearview mirrors, displays, electronic paper, and camouflage applications. Low-E glass is a type of low-emissivity glass that works by reflecting most infrared radiation, reducing heat entering the room. Insulating glass reduces heat exchange between the indoor and outdoor spaces. Both aim to reduce indoor cooling energy consumption. However, these two types of windows, and their combinations, only facilitate cooling, not temperature regulation. That is, in cold winters, heat still struggles to enter the room.

[0003] Traditional electrochromic devices mainly consist of five thin films: two transparent conductive layers, an ion storage layer, an electrochromic layer, and an ion conduction layer. The ion storage layer assists the electrochromic layer in achieving the electrochromic reaction by applying a low voltage to the first and second conductive layers. The ion conduction layer provides lithium ions and diffuses the thin film, ensuring ion conductivity under an electric field. Its structure and fabrication process are among the most important technologies for guaranteeing the electrochromic performance of the device.

[0004] Electrochromic devices can be classified into three types based on the state of the ion-conducting layer: liquid electrochromic devices, gel electrochromic devices, and all-solid-state electrochromic devices. Liquid electrochromic devices exhibit low resistance during ion migration, high ion conductivity, fast electrochromic speed, and high transparency, and are simple to prepare and easy to fill; however, they suffer from problems such as leakage, corrosion, and uneven distribution, requiring extremely high and precise filling and sealing techniques. With repeated cycles of the electrochromic reaction, the ion concentration of the electrolyte tends to become unstable, causing a significant deterioration in the performance of the electrochromic device; the H+ in acidic electrolytes... +Ions corrode electrochromic thin film materials, which is detrimental to long-term use. Furthermore, organic electrolytes have poor safety; for example, LiClO4 is prone to explosion and unsuitable for long-term storage and transportation. Organic solvents are also susceptible to high temperatures and have poor chemical stability, leading to uneven device coloring. Gel-based electrochromic devices utilize a gel-like ion-conducting layer formed by incorporating certain conductive polymers into a liquid ion-conducting layer. This gel-like (quasi-solid-state) ion-conducting layer lies between solid and liquid states, exhibiting higher ionic conductivity than liquid electrolytes. It possesses excellent flexibility and adhesion, reducing damage from splashes of hard materials like glass when the device is subjected to external force. However, its mechanical strength and uniformity are poor, failing to meet the requirements for large-scale industrial production. All-solid-state electrochromic devices offer structural stability and good resistance to water, oxygen, and ultraviolet radiation, avoiding the shortcomings of liquid and quasi-solid-state devices.

[0005] However, due to the different coefficients of thermal expansion between the electrolyte layer and other film layers, the thermal expansion and contraction of the resin-based gel electrolyte layer during operation in high or low temperature environments will cause microcracks or other defects in the film layer and its interface. These defects will trap migrating cations, forming bad spots that cannot fade properly, leading to device failure. Therefore, the application of electrochromic devices in high-latitude or low-latitude regions faces significant limitations. Summary of the Invention

[0006] To address the technical problem that the electrochromic performance of existing electrochromic devices rapidly declines in extreme high / low temperature environments, limiting their application scope and fields, this invention provides an electrochromic device with strong high and low temperature tolerance, comprising: a first transparent electrode, an electrochromic layer, a composite gel electrolyte layer, and a second transparent electrode stacked sequentially; the composite gel electrolyte layer is obtained by coating and curing a mixed solution of alginate solution and a cation-containing resin slurry.

[0007] In this disclosure, covalent-like hydrogen bonds are introduced into the electrolyte layer to form strong bonds with the polar groups in the electrolyte matrix material. This hydrogen bond enhancement method improves the toughness and strength of the electrolyte layer, thereby enhancing the stability of the device in high or low temperature environments. The composite gel electrolyte layer refers to a reinforced electrolyte formed by combining alginate with a resin matrix, which still exhibits excellent electrochemical activity at low temperatures.

[0008] Preferably, the alginate solution has a mass concentration of 0.5 wt% to 5 wt%; the solvent of the alginate solution is at least one of PMA, NMP, and EMC; and the alginate is selected from at least one of sodium alginate, aluminum alginate, magnesium alginate, and calcium alginate. The purpose of adding alginate is to form hydrogen bonds with the electrolyte, thereby improving the electrolyte's toughness and strength at low temperatures. If the addition amount is too low, the desired purpose will not be achieved; if the addition amount is too high, the composite electrolyte layer will be too dense, reducing ion migration channels and affecting the device's response speed and cycle stability.

[0009] Preferably, the alginate solution further contains a ligand selected from at least one of 8-hydroxyquinoline, ethylenediamine, EDTA, β-glucanolactone, glucono-α-lactone, and glucono-δ-lactone, with a concentration of 1-5%. The concentration is the concentration of the ligand relative to the total concentration. The composite gel electrolyte layer is prepared by configuring a cationic precursor slurry based on a photocurable resin, and further adding alginate components rich in covalent bonds. The cations not only induce electrochromic changes under an electric field but also act as crosslinking ions to promote the gelation reaction of the sodium alginate solution. Furthermore, the crosslinking strength between alginate ions and the organic electrolyte is adjusted by the proportion of alginate added. The crosslinking rate of the alginate is controlled by adding an appropriate amount of ligand.

[0010] Preferably, the cation-containing resin slurry comprises a solvent, a stabilizer, a curing resin, an organic precursor, and an ion source; preferably, the ratio of the solvent, stabilizer, curing resin, organic precursor, and ion source is (0.5-2):(0.1-3):(1-10):(0.05-5):1, more preferably 1:1:2:0.1:1.

[0011] Preferably, the solvent is selected from at least one of PMA, NMP, and EMC;

[0012] The stabilizer is selected from at least one of ferrocene, manganese ferrocene, and vinyl ferrocene;

[0013] The curing resin is selected from at least one of ultraviolet light curing resin, PVB resin, silicone resin and acrylic resin;

[0014] The organic precursor is selected from at least one of ETPTA, TMPTA and trimethylolpropane triacrylate;

[0015] The ion source is selected from at least one of Al ion salt, Mg ion salt and Ca ion salt, preferably at least one of magnesium perchlorate, calcium perchlorate and aluminum perchlorate.

[0016] Preferably, the mass ratio of the alginate solution to the cation-containing resin slurry is (1-50)%:1.

[0017] Preferably, an adhesion promoter and a leveling agent are also added to the mixed solution;

[0018] The adhesion promoter is selected from at least one of BYK4500, BYK4509, BYK4510, BYK4511 and BYK4512, and the amount added is 0.1 to 5 wt%.

[0019] The leveling agents BYK333, BYK358N, BYK306 and BYK378 are added in an amount of 0.5-2%.

[0020] Preferably, the coating method is spin coating, and the spin coating speed is 1000-3000 rpm; the thickness of the composite gel electrolyte layer is 20 μm-80 μm. The curing method is ultraviolet light curing or thermal curing.

[0021] The ultraviolet light curing treatment has a power of 50-200W and a time of 5-60s; the thermal curing treatment has a temperature of 50-80℃ and a time of 30-120 minutes.

[0022] Preferably, the electrochromic layer is an inorganic electrochromic layer, and the material is selected from at least one of WO3, MoO3 and TiO2; the thickness of the electrochromic layer is 100-500 nm.

[0023] Preferably, the first and second transparent electrodes are made of at least one material selected from transparent conductive oxides and metal nanowires; the sheet resistance of the first and second transparent electrodes is 10–40 Ω / cm. 2 Transmittance ≥75% (average value in the visible light band).

[0024] Preferably, the electrochromic device exhibits a regulation capability attenuation of ≤10% after 5000 cycles at -80℃ to 150℃. This value indicates that the device has excellent low-temperature resistance.

[0025] Beneficial effects:

[0026] 1. This invention enhances the toughness and strength of the composite gel through strong hydrogen bonding between alginate and the electrolyte resin network via covalent bonds;

[0027] 2. In this invention, the composite gel electrolyte layer maintains good stability of electrochromic properties in both low-temperature and high-temperature environments;

[0028] 3. The cation exchanger in this device acts as a conductive ion, causing the device to change color and promoting alginate gelation, thus avoiding the introduction of other cross-linking ions and preventing a decline in device performance.

[0029] 4. The preparation method developed in this invention has a simple process, a short preparation cycle, and does not require additional equipment.

[0030] In summary, the electrochromic device designed and prepared in this invention maintains stable electrochromic performance under extreme high and low temperature environments. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the electrochromic device structure of the present invention;

[0032] Figure 2 The electrochromic performance of the electrochromic device in Example 1 at low temperature;

[0033] Figure 3 The electrochromic performance of the electrochromic device in Example 1 at high temperature is shown. Detailed Implementation

[0034] The present invention will be further illustrated by the following embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the present invention.

[0035] The inventors have discovered that, due to the different coefficients of thermal expansion between the electrolyte layer and other film layers, thermal expansion and contraction of the resin-based gel electrolyte layer during operation in high or low temperature environments will cause microcracks or other defects at the film layer and its interface. These defects will trap migrating cations, forming bad spots that cannot fade properly, leading to device failure. Therefore, the application of electrochromic devices in high-latitude or low-latitude regions faces significant limitations.

[0036] Therefore, this invention proposes a hydrogen bond enhancement method to improve the toughness and strength of the electrolyte layer, thereby enhancing the device's tolerance to high and low temperature environments. In this patent, the gel electrolyte refers to a cured resin containing cationic groups. A cationic solution is dispersed in the resin slurry, and appropriate auxiliary agents are added to improve resin performance. Alginate is chosen in this patent because, firstly, it is safe and environmentally friendly. Secondly, its hydrogen bonds can form strong bonds with polar groups in the electrolyte matrix material, using hydrogen bond enhancement to improve the toughness and strength of the electrolyte layer and enhance the device's stability in high or low temperature environments. Thirdly, it is easy to adjust; the degree of polymerization of alginate can be adjusted through a simple drawing method.

[0037] Specifically, the electrochromic device with strong high and low temperature tolerance includes: a first transparent electrode, an electrochromic layer, a composite gel electrolyte layer, and a second transparent electrode stacked sequentially.

[0038] The composite gel electrolyte layer is composed of resin and alginate rich in covalent bonds. The cations in this layer not only induce electrochromic changes under an electric field but also act as crosslinking ions to promote the gelation reaction of the sodium alginate solution. Furthermore, the crosslinking strength between alginate ions and the organic electrolyte is adjusted by the proportion of alginate added. The crosslinking rate of alginate is controlled by adding an appropriate amount of ligand. The thickness of the composite gel layer is 20-80 μm. This gel electrolyte layer is a cation-conducting layer based on organic resin, wherein the cations are Al. 3+ Mg 2+ and Ca 2+ At least one of the following, wherein the organic resin is one or more of ultraviolet-curable resin, PVB resin, silicone resin, and acrylic resin.

[0039] The inorganic electrochromic layer is made of at least one of WO3, MoO3, and TiO2, and has a thickness of 100–500 nm. Methods for preparing the electrochromic layer include magnetron sputtering, laser pulse deposition, molecular beam epitaxy, spin coating, spraying, or dip coating.

[0040] The materials of the first and second transparent electrodes are independently selected from at least one of transparent conductive oxides and metal nanowires, with a sheet resistance of 10–40 Ω / cm. 2 Transmittance ≥75%.

[0041] The following example illustrates the fabrication process of an electrochromic device.

[0042] The DC magnetron sputtering system equipment used in the magnetron sputtering deposition of the present invention may include a deposition chamber, a sample inlet chamber, several target heads, a substrate, a DC current, and a series of mechanical pumps and vacuum pumps, wherein the target head is at a certain angle to the substrate and is separated by a certain distance, and the DC power supply is connected to the target head.

[0043] The substrate was ultrasonically cleaned with acetone, anhydrous ethanol, and deionized water for 20 minutes each, and then dried with compressed air. A portion of the conductive substrate was covered with high-temperature tape to serve as an electrode and fixed on the substrate tray. The tray was placed in the sample injection chamber, and the mechanical pump was turned on to evacuate to below 5 Pa. Then, the baffle valve was opened, and the vacuum level (baseline vacuum) was increased to 10. -4 Splash chambers with Pa and below.

[0044] The specific sputtering deposition process is as follows: High-purity argon and oxygen are introduced into the sputtering chamber, with the purity of the argon and oxygen being 99.99% or higher. The total pressure and oxygen partial pressure within the chamber are controlled within the ranges of 0.5–2.0 Pa and 0–50%, respectively, with the oxygen partial pressure preferably being 0–25%. The vertical distance between the target and the substrate is controlled to be 10–20 cm, and the initial substrate temperature is room temperature. The DC power supply is turned on, and the power is controlled to be 30–200 W. The pre-sputtering time is 5–30 min, the sputtering time is 10–60 min, and the substrate temperature is room temperature. After sputtering, the substrate is removed after the substrate temperature has cooled to room temperature.

[0045] As an example of preparing an electrochromic thin film, the process includes: selecting a transparent conductive glass substrate and continuously depositing an inorganic electrochromic layer on its surface. The film is prepared by magnetron sputtering using tungsten, molybdenum, or titanium as the target material, with argon and oxygen as the sputtering gases, a total pressure of 0.5–2.0 Pa, an oxygen partial pressure of 0–50%, a target-substrate distance of 10–20 cm, an initial substrate temperature of room temperature, and a DC power supply of 30–150 W or a power density of 0.6–3.0 W / cm² applied to the target. 2 An electrochromic layer film with a thickness of 100nm–500nm is deposited on the surface using a DC power supply.

[0046] Prepare an alginate precursor solution. Prepare a sodium alginate solution with a mass fraction of 0.5% to 5%, and add 0.5% to 2% of a complexing agent. The complexing agent is at least one selected from ethylenediamine, 8-hydroxyquinoline, and ethylenediaminetetraacetic acid.

[0047] An electrolyte layer precursor solution comprising solvent, stabilizer, photocurable resin, precursor, and ion source is prepared in a mass ratio of 1:1:2:0.1:1. The ion source may be at least one of magnesium perchlorate, calcium perchlorate, and aluminum perchlorate.

[0048] The alginate precursor solution and the electrolyte layer precursor solution were mixed and stirred at a volume ratio of (1-50)%:1 to obtain a mixed solution. An adhesion promoter and a leveling agent were then added to the solution at proportions of 0.1-5% and 0.5-2%, respectively.

[0049] The mixed solution is deposited on the surface of the electrochromic layer using a spin coating process at a rotation speed of 1000-3000 rpm, resulting in a film thickness of 20-80 μm.

[0050] After spin coating is completed, cover with the top electrode.

[0051] The prepared device is cured by ultraviolet light (e.g., uniform irradiation with a 100-300W ultraviolet lamp for 10-60 seconds) or by heat curing (50-80℃ for 30-120 minutes).

[0052] After the device has cured, an organic solvent is used to remove excess organic matter from the device surface. This completes the preparation process of the all-solid-state electrochromic device.

[0053] The following examples further illustrate the present invention in detail. It should also be understood that the following examples are only for further explanation of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of the present invention are within the scope of protection of the present invention. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the appropriate range based on the description herein, and are not intended to be limited to the specific values ​​in the examples below.

[0054] Example 1

[0055] (1) An inorganic electrochromic layer was continuously deposited on a transparent conductive glass ITO substrate. The layer was prepared by magnetron sputtering using tungsten as the target material and argon and oxygen as the sputtering gases. The total pressure was 1.5 Pa, the oxygen partial pressure was 15%, the distance between the target and the substrate was 15 cm, the initial substrate temperature was room temperature, and the applied DC power to the target was 100 W or the power density was 2.0 W / cm². 2 A 400nm electrochromic thin film was deposited on the surface using a DC power supply;

[0056] (2) Preparation of Alginate Precursor Solution. Prepare a 2% sodium alginate solution and add 1% of a complexing agent, namely 8-hydroxyquinoline. Prepare an electrolyte layer precursor solution containing solvent, stabilizer, photocurable resin, precursor, and ion source in a ratio of 1:1:2:0.1:1. The ion source is aluminum perchlorate, the solvent is propylene carbonate, the stabilizer is ferrocene, the photocurable resin is Jiangsu Taiter Co., Ltd. brand TTA21, and the precursor is ETPTA (ethoxylated trimethylolpropane triacrylate). Mix the alginate solution and the photocurable resin solution at a ratio of 30%:1, and further add an adhesion promoter and a leveling agent to the solution at a ratio of 1% and 1% of the total mass of the precursor slurry, respectively.

[0057] (3) The above mixed solution was deposited onto the surface of the electrochromic layer using a spin-coating process at a rotation speed of 2500 rpm, resulting in a film thickness of 60 μm. After spin-coating, the top electrode was applied. The prepared device was then uniformly irradiated under a 100W UV lamp for 15 seconds. After the device cured, excess organic matter on the device surface was removed using an organic solvent. This completed the preparation process of the all-solid-state electrochromic layer.

[0058] Example 2

[0059] The preparation process of the electrochromic device in Example 2 is the same as that in Example 1, except that in step (2), the alginate solution and the photocurable resin solution are mixed and stirred in a ratio of 1%:1, and an adhesion promoter and a leveling agent are added to the solution in a ratio of 1% and 1% respectively.

[0060] Example 3

[0061] The preparation process of the electrochromic device in Example 3 is the same as that in Example 1, except that in step (2), the alginate solution and the photocurable resin solution are mixed and stirred in a ratio of 50%:1, and an adhesion promoter and a leveling agent are added to the solution in a ratio of 1% and 1%, respectively.

[0062] Example 4

[0063] The preparation process of the electrochromic device in Example 4 is the same as that in Example 1, except that the thickness of the electrochromic layer film is 100nm in step (1).

[0064] Example 5

[0065] The preparation process of the electrochromic device in Example 5 is the same as that in Example 1, except that the thickness of the electrochromic layer film is 500 nm in step (1).

[0066] Example 6

[0067] The preparation process of the electrochromic device in Example 6 is the same as that in Example 1, except that in step (3), the above mixed solution is deposited on the surface of the electrochromic layer by spin coating at a rotation speed of 1000 rpm and a film thickness of 80 μm.

[0068] Example 7

[0069] The preparation process of the electrochromic device in Example 7 is the same as that in Example 1, except that in step (3), the above mixed solution is deposited on the surface of the electrochromic layer by spin coating at a rotation speed of 3000 rpm and a film thickness of 20 μm.

[0070] Example 8

[0071] The preparation process of the electrochromic device in Example 8 is the same as that in Example 1, except that in step (2), a sodium alginate solution with a mass fraction of 0.5% is prepared and a 0.5% ligand is added, wherein the ligand is 8-hydroxyquinoline.

[0072] Example 9

[0073] The preparation process of the electrochromic device in Example 9 is the same as that in Example 1, except that in step (2), a sodium alginate solution with a mass fraction of 5% is prepared and a 2% complexing agent is added, wherein the complexing agent is 8-hydroxyquinoline.

[0074] Example 10

[0075] The preparation process of the electrochromic device in Example 10 is the same as that in Example 1, except that in step (2), the alginate solution and the photocurable resin solution are mixed and stirred in a ratio of 30%:1. Furthermore, an adhesion promoter and a leveling agent are added to the solution, with the addition ratios being 0.1% and 0.5% of the total mass of the precursor slurry, respectively.

[0076] Example 11

[0077] The preparation process of the electrochromic device in Example 11 is the same as that in Example 1, except that in step (2), the alginate solution and the photocurable resin solution are mixed and stirred in a ratio of 30%:1. Furthermore, an adhesion promoter and a leveling agent are added to the solution, with the addition ratios being 5% and 2% of the total mass of the precursor slurry, respectively.

[0078] Example 12

[0079] The preparation process of the electrochromic device in Example 12 is the same as that in Example 1, except that in step (2), the ion source is magnesium perchlorate.

[0080] Example 13

[0081] The preparation process of the electrochromic device in this embodiment 13 is the same as that in embodiment 1, except that in step (2), the ion source is calcium perchlorate.

[0082] Example 14

[0083] The fabrication process of the electrochromic device in Example 14 is the same as in Example 1, except that in step (1), molybdenum is used as the target material by magnetron sputtering, the sputtering gas is argon and oxygen, the total pressure is 1.5 Pa, the oxygen partial pressure is 15%, the distance between the target material and the substrate is 15 cm, the initial substrate temperature is room temperature, and the DC power applied to the target material is 100 W or the power density is 2.0 W / cm². 2 A 400nm electrochromic layer film was deposited on the surface using a DC power supply.

[0084] Example 15

[0085] The fabrication process of the electrochromic device in Example 15 is the same as in Example 1, except that in step (1), titanium metal is used as the target material by magnetron sputtering, the sputtering gas is argon and oxygen, the total pressure is 1.5 Pa, the oxygen partial pressure is 15%, the distance between the target material and the substrate is 15 cm, the initial substrate temperature is room temperature, and the DC power applied to the target material is 100 W or the power density is 2.0 W / cm². 2 A 400nm electrochromic layer film was deposited on the surface using a DC power supply.

[0086] Example 16

[0087] The preparation process of the electrochromic device in Example 16 is the same as that in Example 1, except that in step (2), a sodium alginate solution with a mass fraction of 2% is prepared and a 1% complexing agent is added, wherein the complexing agent is ethylenediamine.

[0088] Example 17

[0089] The preparation process of the electrochromic device in Example 17 is the same as that in Example 1, except that in step (2), a sodium alginate solution with a mass fraction of 2% is prepared and a 1% complexing agent is added, wherein the complexing agent is ethylenediaminetetraacetic acid.

[0090] Example 18

[0091] The preparation process of the electrochromic device in Example 18 is the same as that in Example 1, except that in step (2), the alginate solution and the photocurable resin solution are mixed and stirred in a ratio of 5%:1, and an adhesion promoter and a leveling agent are added to the solution in a ratio of 1% and 1%, respectively.

[0092] Example 19

[0093] The preparation process of the electrochromic device in Example 19 is the same as that in Example 1, except that in step (2), the alginate solution and the photocurable resin solution are mixed and stirred in a ratio of 10%:1, and an adhesion promoter and a leveling agent are added to the solution in a ratio of 1% and 1%, respectively.

[0094] Example 20

[0095] The preparation process of the electrochromic device in this embodiment 20 is the same as that in embodiment 1, except that in step (2), the alginate solution and the photocurable resin solution are mixed and stirred in a ratio of 20%:1, and an adhesion promoter and a leveling agent are added to the solution in a ratio of 1% and 1%, respectively.

[0096] Example 21

[0097] The preparation process of the electrochromic device in this embodiment 21 is the same as that in embodiment 1, except that in step (2), the alginate solution and the photocurable resin solution are mixed and stirred in a ratio of 40%:1, and an adhesion promoter and a leveling agent are added to the solution in a ratio of 1% and 1%, respectively.

[0098] Comparative Example 1

[0099] The preparation process of the electrochromic device in Comparative Example 1 is the same as that in Example 1, except that in step (2), the alginate solution and the photocurable resin solution are mixed and stirred in a ratio of 0%:1, and an adhesion promoter and a leveling agent are added to the solution in a ratio of 1% and 1%, respectively.

[0100] Comparative Example 2

[0101] The preparation process of the electrochromic device in Comparative Example 2 is the same as that in Example 1, except that in step (2), the alginate solution and the photocurable resin solution are mixed and stirred in a ratio of 60%:1, and an adhesion promoter and a leveling agent are added to the solution in a ratio of 1% and 1%, respectively.

[0102] In this invention, the ability of the electrochromic device to withstand high or low temperatures refers to the ability of the device to maintain its adjustment capability attenuation by ≤10% after 5000 continuous cycles at that temperature. The adjustment range is the average adjustment capability of the device at a wavelength of 670nm within its operating temperature range.

[0103] Table 1 shows the temperature range that the devices prepared in the examples and comparative examples can withstand:

[0104]

[0105]

Claims

1. An electrochromic device with strong high and low temperature resistance, characterized in that, include: The first transparent electrode, the electrochromic layer, the composite gel electrolyte layer, and the second transparent electrode are stacked in sequence. The composite gel electrolyte layer is obtained by coating and curing a mixture of alginate solution and a cation-containing resin slurry.

2. The electrochromic device according to claim 1, characterized in that, The alginate solution has a mass concentration of 0.5wt% to 5wt%; the solvent of the alginate solution is at least one of PMA, NMP and EMC; the alginate is selected from at least one of sodium alginate, aluminum alginate, magnesium alginate and calcium alginate.

3. The electrochromic device according to claim 2, characterized in that, The alginate solution also contains a ligand selected from at least one of 8-hydroxyquinoline, ethylenediamine, EDTAβ-glucanolactone, gluconic acid-α-lactone, and gluconic acidδ-lactone, with a concentration of 1-5 wt%.

4. The electrochromic device according to claim 1, characterized in that, The cation-containing resin slurry includes a solvent, a stabilizer, a curing resin, an organic precursor, and an ion source; the mass ratio of the solvent, stabilizer, curing resin, organic precursor, and ion source is (0.5-2):(0.1-3):(1-10):(0.05-5):

1.

5. The electrochromic device according to claim 4, characterized in that, The ratio of the solvent, stabilizer, curing resin, organic precursor and ion source is 1:1:2:0.1:

1.

6. The electrochromic device according to claim 4, characterized in that, The solvent is selected from at least one of PMA, NMP, and EMC; The stabilizer is selected from at least one of ferrocene, manganese ferrocene, and vinyl ferrocene; The curing resin is selected from at least one of ultraviolet light curing resin, PVB resin, silicone resin and acrylic resin; The organic precursor is selected from at least one of ETPTA, TMPTA and trimethylolpropane triacrylate; The ion source is selected from at least one of Al ion salts, Mg ion salts, and Ca ion salts.

7. The electrochromic device according to claim 6, characterized in that, The ion source is at least one of magnesium perchlorate, calcium perchlorate, and aluminum perchlorate.

8. The electrochromic device according to claim 1, characterized in that, The mass ratio of the alginate solution to the cation-containing resin slurry is (1% to 50%):

1.

9. The electrochromic device according to claim 1, characterized in that, The mixed solution also contains adhesion promoters and leveling agents; The adhesion promoter is selected from at least one of BYK4500, BYK4509, BYK4510, BYK4511 and BYK4512, and is added in an amount of 0.1 to 5 wt%. The leveling agent is BYK333, BYK358N, BYK306 and BYK378, and the amount added is 0.5 to 2 wt%.

10. The electrochromic device according to claim 1, characterized in that, The coating method is spin coating, and the spin coating speed is 1000-3000 rpm; The curing method is ultraviolet light curing or thermal curing; the power of ultraviolet light curing is 50-200W, and the time is 5-60s; the temperature of thermal curing is 50-80℃, and the time is 30-120 minutes. The thickness of the composite gel electrolyte layer is 20 μm to 80 μm.

11. The electrochromic device according to claim 1, characterized in that, The electrochromic layer is an inorganic electrochromic layer, and the material is selected from at least one of WO3, MoO3 and TiO2; the thickness of the electrochromic layer is 100-500 nm.

12. The electrochromic device according to claim 1, characterized in that, The first and second transparent electrodes are made of at least one material selected from transparent conductive oxides and metal nanowires; the sheet resistance of the first and second transparent electrodes is 10–40 Ω / cm. 2 The average transmittance in the visible light band is ≥75%.

13. The electrochromic device according to claim 1, characterized in that, The electrochromic device undergoes 5000 cycles at -80℃ to 150℃, with its adjustment capability decreasing by ≤10%.

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