Film coating device for inhibiting lithium migration in electrochromic device and application of film coating device

Abstract

The invention provides a coating device for inhibiting lithium migration in an electrochromic device and application of the coating device. The coating device comprises a vacuum cavity, a direct-current power supply, at least two upper transmission devices, at least two lower transmission devices and a substrate loading frame, the upper transmission device and the lower transmission device are respectively, independently and fixedly arranged in the vacuum cavity; the direct-current power supply is connected with the upper transmission device through a cathode power line; and the substrate loading frame is fixedly loaded through the upper transmission device and the lower transmission device. Negative bias voltage is provided for the substrate loading frame through the direct-current power source, in the electrochromic film plating process, lithium ions are stably fixed to the surface of a cathode electrochromic layer, and the stability problem of active metal lithium is fundamentally solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrochromism, and particularly relates to a coating device and method for inhibiting lithium migration in electrochromic devices. Background Art

[0002] Due to its unique optical properties, electrochromic devices can reversibly change color and transmittance under the action of an electric field, showing broad application prospects in many fields such as smart windows, electronic displays, automotive rearview mirrors, and energy-saving buildings. Taking smart windows as an example, by regulating the color and transmittance of the device, not only can indoor lighting and temperature be effectively adjusted, building energy consumption be reduced, but also user privacy protection can be significantly improved; in the field of automotive rearview mirrors, its application can reduce glare and improve driving safety.

[0003] Among many electrochromic systems, electrochromic devices based on lithium-ion transport have become the focus of research and application due to their excellent color-changing performance and response speed. However, during the actual use of such devices, the phenomenon of lithium migration brings many serious problems. On the one hand, the non-uniform migration of lithium inside the device will cause changes in the structure and composition of the electrochromic layer and the counter electrode layer, resulting in the degradation of the color-changing performance of the device, such as a decrease in color-changing contrast and a slowdown in response speed, which greatly affects the user experience. On the other hand, lithium migration will also cause short circuits inside the device, significantly shortening the service life of the device, and severely limiting the large-scale commercial application of electrochromic devices.

[0004] Generally speaking, an electrochromic thin film includes a first transparent conductive layer, a cathode electrochromic layer, a dielectric layer, an ion conduction layer, an anode electrochromic layer, and a second transparent conductive layer arranged in a stacked manner. To solve the problem of lithium migration, currently, efforts are mainly focused on material optimization and structural design. In terms of material selection, CN 117784487A discloses an electrolyte and its preparation method, and an electrochromic device, which controls the migration behavior of lithium ions by optimizing the composition and preparation process of the electrolyte. However, this method often has problems such as complex preparation processes and high costs, making it difficult to achieve large-scale industrial production. In terms of structural design, a barrier layer is introduced to inhibit lithium migration, but the barrier effect of traditional barrier layer materials is poor, which may have a negative impact on the overall performance of the device, such as reducing the optical transmittance and color-changing efficiency of the device.

[0005] Coating technology plays a key role in the preparation process of electrochromic devices, and it can precisely control the thickness and performance of each layer of the device. However, existing coating devices and methods have obvious deficiencies in inhibiting lithium migration. On the one hand, traditional coating methods are difficult to form a uniform and dense barrier layer inside the device, and cannot effectively block the migration of lithium. On the other hand, impurities are easily introduced during the coating process, further exacerbating the lithium migration phenomenon and affecting the performance and stability of the device.

[0006] In summary, developing a coating device and method that can effectively inhibit lithium migration in electrochromic devices is of great practical significance for improving the performance of electrochromic devices and promoting their wide application in various fields. Summary of the Invention

[0007] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a coating device for inhibiting lithium migration in electrochromic devices and its application. The present invention provides a negative bias voltage for the substrate loading rack through a DC power supply, and during the process of depositing the electrochromic film, the lithium ions are stably fixed on the surface of the cathode electrochromic layer, fundamentally solving the stability problem of active metal lithium.

[0008] To achieve the purpose of this invention, the following technical solutions are adopted:

[0009] In the first aspect, the present invention provides a coating device for inhibiting lithium migration in electrochromic devices, which includes a vacuum chamber, a DC power supply, at least two upper driving devices, at least two lower driving devices, and a substrate loading rack;

[0010] The upper driving device and the lower driving device are respectively and independently fixedly arranged inside the vacuum chamber;

[0011] The DC power supply is connected to the upper driving device through a cathode power line;

[0012] The substrate loading rack is fixedly loaded and arranged through the upper driving device and the lower driving device.

[0013] Through the optimization and transformation of the magnetron sputtering equipment, the present invention realizes providing an additional negative bias voltage for the substrate loading rack by using a DC power supply, so as to balance the traction force in the cathode direction, and further enables the lithium ions in the dielectric layer not to migrate during the coating process, and is completely controlled on the surface of the cathode electrochromic layer.

[0014] As a preferred technical solution of the present invention, the upper driving device and the lower driving device respectively and independently include a fixedly arranged support shaft and a transmission wheel.

[0015] As a preferred technical solution of the present invention, through holes are respectively and independently arranged at the top and bottom of the vacuum chamber.

[0016] Preferably, the support shaft is fixedly installed with the transmission wheel through the through hole.

[0017] It should be noted that the support shaft penetrates through the through hole, and the end of the support shaft exposed in the vacuum chamber is connected to the cathode of the DC power supply through a cathode power line.

[0018] As a preferred technical solution of the present invention, an insulating ring is provided at one end of the support shaft close to the transmission wheel.

[0019] Preferably, an insulating ring is arranged on the inner periphery of the through hole.

[0020] Preferably, the insulating ring is made of polyether ether ketone (PEEK).

[0021] It should be noted that the insulating ring has excellent insulation and wear resistance, which can avoid direct contact between the through hole and the support shaft and prevent short - circuit between the support shaft and the vacuum chamber.

[0022] As a preferred technical solution of the present invention, the transmission wheel is used to load and move the substrate loading rack.

[0023] More specifically, the substrate loading rack is used to load the substrates to be coated.

[0024] As a preferred technical solution of the present invention, the positive terminal of the DC power supply is grounded.

[0025] In a second aspect, the present invention provides an application of a coating device for suppressing lithium migration in an electrochromic device as provided in the first aspect, and the coating device is used for coating the anodic electrochromic layer in the electrochromic film.

[0026] As a preferred technical solution of the present invention, the applied voltage of the DC power supply during the coating is 3 - 12V. For example, it can be 3V, 5V, 7V, 9V or 12V, etc., but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0027] In the present invention, the applied negative bias voltage during the coating is 3 - 12V. If the voltage is too high, it will cause lithium ions to penetrate too deep into the cathodic electrochromic layer and cannot move during the coating of the dielectric lithium layer; conversely, if the voltage is too low, it will cause lithium ions not to be fully bound during the coating of the dielectric lithium layer, and some will move towards the cathode of the target.

[0028] As a preferred technical solution of the present invention, the coating pressure during the coating is 0.5 - 4Pa. For example, it can be 0.5Pa, 1Pa, 2Pa, 3Pa or 4Pa, etc., but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0029] Preferably, the coating temperature during the coating is 50 - 150°C. For example, it can be 50°C, 100°C, or 150°C, etc., but is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0030] As a preferred technical solution of the present invention, the moving speed of the driving wheel during plating is 0.1 to 1 m / min. For example, it can be 0.1 m / min, 0.2 m / min, 0.4 m / min, 0.6 m / min, 0.8 m / min or 1 m / min, etc., but not limited to the listed values. Other unlisted values within the numerical range are equally applicable.

[0031] Preferably, the vacuum degree inside the vacuum chamber during plating is 10 -3 ~10 -5 Pa. For example, it can be 10 -3 Pa, 10 -4 Pa or 10 -5 Pa, etc., but not limited to the listed values. Other unlisted values within the numerical range are equally applicable.

[0032] By applying a negative bias voltage during the plating of the anodic electrochromic layer, the present invention achieves a balance with the attraction of the opposite cathode during the plating of the anodic electrochromic layer, preventing the migration of lithium ions.

[0033] The numerical ranges described in the present invention include not only the point values listed above, but also any point values between the above numerical ranges that are not listed. Due to space limitations and for the sake of brevity, the present invention does not exhaustively list the specific point values included in the range.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) By providing a negative bias voltage to the substrate loading rack through a DC power supply, the present invention realizes the stable fixation of lithium ions on the surface of the cathodic electrochromic layer during the plating of the electrochromic thin film, fundamentally solving the stability problem of active metal lithium.

[0036] (2) The coating device provided by the present invention has a simple structure, low transformation cost, and simple operation, and has broad market prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic structural diagram of a coating device for suppressing lithium migration in an electrochromic device provided by a specific embodiment of the present invention;

[0038] Wherein 1 is a vacuum chamber, 2 is a DC power supply, 3 is an upper driving device, 4 is a lower driving device, 5 is a substrate loading rack, 6 is a cathode power line, 7 is a support shaft, 8 is a driving wheel, and 9 is an insulating ring. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] The technical solution of the present invention will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only for helping to understand the present invention and should not be regarded as specific limitations on the present invention.

[0040] In a specific embodiment, the present invention provides a coating device for suppressing lithium migration in an electrochromic device, as Figure 1 shown, the coating device includes: a vacuum chamber 1, a DC power supply 2, at least two upper driving devices 3, at least two lower driving devices 4, and a substrate loading rack 5;

[0041] The upper driving device 3 and the lower driving device 4 are respectively and independently fixedly arranged inside the vacuum chamber 1;

[0042] The DC power supply 2 is connected to the upper driving device 3 through a cathode power line 6;

[0043] The substrate loading rack 5 is fixedly loaded and arranged through the upper driving device 3 and the lower driving device 4.

[0044] The upper driving device 3 and the lower driving device 4 respectively and independently include a fixedly arranged support shaft 7 and a driving wheel 8; through holes are respectively and independently arranged at the top and bottom of the vacuum chamber 1; the support shaft 7 is fixedly installed with the driving wheel 8 through the through hole;

[0045] An insulating ring 9 is provided at one end of the support shaft 7 close to the driving wheel 8; an insulating ring made of PEEK is arranged on the inner periphery of the through hole;

[0046] The driving wheel 8 is used for loading and moving the substrate loading rack 5; the anodic end of the DC power supply 2 is grounded.

[0047] Example 1

[0048] This example provides a coating device for suppressing lithium migration in an electrochromic device, as Figure 1 shown, the coating device includes: a vacuum chamber 1, a DC power supply 2, at least two upper driving devices 3, at least two lower driving devices 4, and a substrate loading rack 5;

[0049] The upper driving device 3 and the lower driving device 4 are respectively and independently fixedly arranged inside the vacuum chamber 1;

[0050] The DC power supply 2 is connected to the upper driving device 3 through a cathode power line 6;

[0051] The substrate loading rack 5 is fixedly loaded and arranged through the upper driving device 3 and the lower driving device 4.

[0052] The upper transmission device 3 and the lower transmission device 4 each independently include a fixedly arranged support shaft 7 and a transmission wheel 8; through holes are respectively and independently arranged at the top and bottom of the vacuum cavity 1; the support shaft 7 is fixedly installed with the transmission wheel 8 through the through hole;

[0053] An insulating ring 9 is provided at one end of the support shaft 7 close to the transmission wheel 8; an insulating ring made of PEEK is arranged on the inner periphery of the through hole;

[0054] The transmission wheel 8 is used for loading and moving the substrate loading rack 5; the positive electrode end of the DC power supply 2 is grounded.

[0055] Embodiment 2

[0056] This embodiment provides a coating device for suppressing lithium migration in an electrochromic device. The difference between this coating device and that of Embodiment 1 is only that:

[0057] In this embodiment, the insulating ring arranged around the support shaft is omitted.

[0058] Comparative Example 1

[0059] This comparative example provides a coating device for suppressing lithium migration in an electrochromic device. The difference between this coating device and that of Embodiment 1 is only that:

[0060] In this comparative example, the setting of the DC power supply 2 is omitted.

[0061] Application Example 1

[0062] This application example provides a method for coating an anode electrochromic layer in an electrochromic thin film by using the coating device for suppressing lithium migration in an electrochromic device provided in Embodiment 1. The method includes:

[0063] Placing the substrate coated with the first transparent conductive layer, the cathode electrochromic layer, the dielectric layer and the ion-conducting layer on the substrate loading rack, and then performing anode electrochromic layer coating under the conditions of a negative bias voltage of 10V, a temperature of 50°C, a pressure of 1.2Pa, and a speed of 0.5m / min.

[0064] Among them, the power density during the coating process of the first transparent conductive layer is 4kw / m, the coating temperature is 300°C, the coating pressure is 0.5Pa, the argon gas flow rate is 300sccm, the oxygen concentration is 0.5%, and the speed is 0.1 - 1.0m / min;

[0065] The power density during the coating process of the cathode electrochromic layer is 15kw / m, the coating temperature is 300°C, the coating pressure is 2.0Pa, the argon gas flow rate is 500sccm, the oxygen concentration is 70%, and the speed is 0.5m / min;

[0066] During the deposition of the medium lithium layer, the power density is 5 kw / m, the coating temperature is 50 °C, the coating pressure is 0.5 Pa, the argon flow rate is 500 sccm, and the speed is 0.5 m / min;

[0067] During the deposition of the ion conduction layer, the power density is 15 kw / m, the coating temperature is 50 °C, the coating pressure is 2.0 Pa, the argon flow rate is 500 sccm, the oxygen concentration is 80%, and the speed is 0.5 m / min.

[0068] Application Example 2

[0069] This application example provides a method for depositing an anode electrochromic layer in an electrochromic thin film by using the coating device provided in Example 1 for suppressing lithium migration in an electrochromic device. The method includes:

[0070] Place the substrate coated with the first transparent conductive layer, the cathode electrochromic layer, the dielectric layer, and the ion conduction layer in the substrate loading rack, and then deposit the anode electrochromic layer under the conditions of a negative bias voltage of 3 V, a temperature of 100 °C, a pressure of 4 Pa, and a speed of 0.1 m / min.

[0071] Application Example 3

[0072] This application example provides a method for depositing an anode electrochromic layer in an electrochromic thin film by using the coating device provided in Example 1 for suppressing lithium migration in an electrochromic device. The method includes:

[0073] Place the substrate coated with the first transparent conductive layer, the cathode electrochromic layer, the dielectric layer, and the ion conduction layer in the substrate loading rack, and then deposit the cathode electrochromic layer on the surface of the first transparent conductive layer under the conditions of a negative bias voltage of 12 V, a temperature of 150 °C, a pressure of 0.5 Pa, and a speed of 0.1 m / min.

[0074] Application Example 4

[0075] This application example provides a method for depositing an anode electrochromic layer in an electrochromic thin film by using the coating device provided in Example 1 for suppressing lithium migration in an electrochromic device. The difference between this method and Application Example 1 is only that:

[0076] In this application example, the applied negative bias voltage is adjusted to 2 V.

[0077] Application Example 5

[0078] This application example provides a method for depositing an anode electrochromic layer in an electrochromic thin film by using the coating device provided in Example 1 for suppressing lithium migration in an electrochromic device. The difference between this method and Application Example 1 is only that:

[0079] In this application example, the applied negative bias voltage is adjusted to 6 V.

[0080] Application Example 6

[0081] This application example provides a method for depositing an anode electrochromic layer in an electrochromic thin film by using the coating device for suppressing lithium migration in an electrochromic device provided in Example 2. The method is the same as that in Application Example 1.

[0082] Application Example 7

[0083] This application example provides a method for depositing an anode electrochromic layer in an electrochromic thin film by using the coating device for suppressing lithium migration in an electrochromic device provided in Example 1. The difference between this method and that in Application Example 1 is only that:

[0084] In this application example, the applied negative bias voltage is adjusted to 9V.

[0085] Application Example 8

[0086] This application example provides a method for depositing an anode electrochromic layer in an electrochromic thin film by using the coating device for suppressing lithium migration in an electrochromic device provided in Example 1. The difference between this method and that in Application Example 1 is only that:

[0087] In this application example, the applied negative bias voltage is adjusted to 15V.

[0088] Application Example 9

[0089] This application example provides a method for depositing an anode electrochromic layer in an electrochromic thin film by using the coating device for suppressing lithium migration in an electrochromic device provided in Example 2. The method is the same as that in Application Example 1.

[0090] Comparative Application Example 1

[0091] This comparative application example provides a method for depositing an anode electrochromic layer in an electrochromic thin film by using the coating device for suppressing lithium migration in an electrochromic device provided in Comparative Example 1. The method is the same as that in Application Example 1.

[0092] Performance Detection:

[0093] On the basis of the substrates provided in the above application examples and comparative application examples, a second transparent conductive layer is deposited to obtain an electrochromic product. The obtained electrochromic product is subjected to appearance detection and light transmittance detection. The results are shown in Table 1;

[0094] According to the human visual experience, in the appearance detection, dark blue is the best, blue is the second, blue-black and light blue are slightly worse, and colorless is the worst;

[0095] Among them, in the process of depositing the second transparent conductive layer, the power density is 4 kw / m, the coating temperature is 20°C, the coating pressure is 1 Pa, the argon flow rate is 300 sccm, the oxygen concentration is 0.5%, and the speed is 0.5 m / min.

[0096] Table 1

[0097] Appearance Transmittance range Application Example 1 Dark blue 2～2.5％ Application Example 2 Light blue 5～6％ Application Example 3 Dark blue 1～1.5％ Application Example 4 Uneven light blue 5～12％ Application Example 5 Blue 3～4％ Application Example 6 Colorless 15～25％ Application Example 7 Dark blue 2.5～3％ Application Example 8 Blue-black ＜1％ Application Example 9 Colorless 15～25％ Comparative Application Example 1 Colorless 15～25％

[0098] As can be seen from Table 1, the following points can be obtained:

[0099] (1) Through comprehensive analysis of Application Examples 1 - 3, it can be known that by using the coating device provided by the present invention, the migration problem of lithium ions in the dielectric lithium layer during the coating process of electrochromic products can be effectively improved, and lithium can be stably fixed on the surface of the cathode electrochromic layer, fundamentally solving the stability problem of active metal lithium;

[0100] (2) Through comprehensive analysis of Application Example 1, Application Examples 4 - 8 and Comparative Application Example 1, it can be known that a reasonable range of negative bias voltage process parameters when using the coating device provided by the present invention is one of the important ways to affect the migration of lithium ions;

[0101] When the negative bias voltage is too low, it will cause that not all lithium ions can be stably bound and do not move; on the contrary, when the negative bias voltage is too high, it will cause deeper penetration into the cathode electrochromic layer and the color to turn black;

[0102] (3) Through comprehensive analysis of Application Example 1 and Application Example 9, it can be known that if the insulating ring disposed around the support shaft is omitted, it will cause the short - circuit failure of the bias voltage device and the vacuum chamber.

[0103] In summary, the present invention provides a negative bias voltage for the substrate loading rack through a DC power supply, and during the process of depositing an electrochromic thin film, it realizes the stable fixation of lithium ions on the surface of the cathode electrochromic layer, fundamentally solving the stability problem of active metal lithium.

[0104] The applicant declares that the above - mentioned is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A coating device for suppressing lithium migration in an electrochromic device, characterized in that, The coating device includes a vacuum chamber, a DC power supply, at least two upper driving devices, at least two lower driving devices, and a substrate loading rack; The upper driving device and the lower driving device are respectively and independently fixedly arranged inside the vacuum chamber; The DC power supply is connected to the upper driving device through a cathode power line; The substrate loading rack is fixedly loaded and arranged through the upper driving device and the lower driving device.

2. The coating device according to claim 1, wherein The upper driving device and the lower driving device respectively and independently include a fixedly arranged support shaft and a driving wheel.

3. The coating device according to claim 2, wherein Through holes are respectively and independently arranged at the top and bottom of the vacuum chamber; Preferably, the support shaft is fixedly installed with the driving wheel through the through hole.

4. The coating device according to claim 3, characterized in that, An insulating ring is provided at one end of the support shaft close to the driving wheel; Preferably, an insulating ring is arranged on the inner periphery of the through hole; Preferably, the insulating ring is made of polyether ether ketone.

5. The coating device according to claim 2, wherein, The driving wheel is used to load and move the substrate loading rack.

6. The coating device according to any one of claims 1-5, characterized in that, The anodic end of the DC power supply is grounded.

7. Use of a coating device for inhibiting lithium migration in an electrochromic device according to any one of claims 1-6, characterized in that, The coating device is used for coating the anodic electrochromic layer in the electrochromic thin film.

8. The application according to claim 7, wherein The applied voltage of the DC power supply during the coating is 3 - 12V.

9. The application according to claim 7 or 8, characterized in that, The coating pressure during the coating is 0.5 - 4 Pa; Preferably, the coating temperature during the coating is 50 - 150 °C.

10. The application according to any one of claims 7-9, characterized in that, The moving speed of the driving wheel during the coating is 0.1 - 1 m / min; Preferably, the vacuum degree inside the vacuum chamber during coating is 10 -3 ~10 -5 Pa.

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