CN104536231B - Electrochromic display device, its preparation method, cathode construction and micro- lattice array - Google Patents

Abstract

The invention discloses an electrochromic display device, a preparation method thereof, a cathode structure and a microgrid array, relates to electrochromic technology, and solves the problem that the cathode material and the anode material are easily polluted by sealing materials in the existing electrochromic display device , and the difficulty of the alignment process during the preparation of the device. In the embodiment of the present invention, because the height of three outer walls in the outer walls around the microgrid array exceeds the height of the microgrid in the microgrid array, a drawer-shaped guide groove with a gap is formed; The same thickness, and the internal size of the drawer-shaped guide groove matches the outer peripheral size of the cathode film with barrier strips, so the drawer principle can be used to ensure that the anode material is completely sealed in a simple way, which simplifies the process difficulty of the alignment process, and The barrier strip and the raised three outer walls seal the sides of the cathode film, avoiding the contamination of the cathode and anode materials by the sealing material.

Description

Electrochromic display device, its preparation method, cathode structure and microgrid array

This application is a divisional application for a Chinese patent application with an application date of May 23, 2011, an application number of 201110134847.5, and an invention title of "Electrochromic Display Device, Its Preparation Method, Cathode Structure, and Microgrid Array".

technical field

The invention relates to electrochromic technology, in particular to an electrochromic display device, a preparation method thereof, a cathode structure and a microgrid array.

Background technique

An electrochromic display device (Electrochromic Device, ECD for short) is widely used in portable electronic devices, such as personal digital processors, electronic paper books, and the like. It has the advantages of low starting voltage, low energy consumption, the pattern displayed after opening the circuit can be stored for a certain period of time without energy consumption, low cost, easy to manufacture, good contrast, and wide viewing angle.

The structure of the existing electrochromic display device is shown in Figure 1, on this first ITO film 12 of the first base material 11 that has the first ITO (indium tin oxide) film 12, be formed with microgrid array 13, each The microcells are filled with anode material 14, which includes electrolyte and materials capable of realizing ion storage function. The microgrid array 13 is sequentially covered with a cathode film 15 , a second ITO film 16 and a second substrate 17 , wherein the cathode film 15 is an electrochromic material layer.

When the existing electrochromic display device is working, a certain voltage is applied between the two ITO films, and the electrochromic material of the cathode film 15 undergoes an oxidation/reduction reaction under the action of the voltage, causing the color to change or restore the original color. The electrolyte is composed of conductive materials to provide the ions required for the oxidation/reduction reaction; the material that can realize the ion storage function stores the corresponding counter ions when the electrochromic material undergoes a redox reaction, so that the entire system maintains charge balance.

The method for manufacturing the conventional electrochromic display device shown in FIG. 1 includes the following steps.

Step 1. Prepare the cathode part. After the second ITO film 16 is formed on the second substrate 17 , the cathode material is coated on the second ITO film 16 and then dried to form the cathode film 15 .

Step 2, preparing the anode part. After forming the first ITO thin film 12 on the first base material 11, a layer of radiation curing material is coated on the first ITO thin film 12, it is light-cured through a photomask plate and then the unexposed part is washed away to obtain a microstructure. grid array 13, and then pour the anode material 14 into the micro grid array 13 by scraping or filling. The peripheral dimensions of the microgrid array 13 are the same as the peripheral dimensions of the cathode film 15 .

Step 3, fit. After the cathode film 15 is aligned with the microgrid array 13 , the cathode part and the anode part are aligned and bonded to form a box-like structure, and the cathode film 15 covers the microgrid array 13 .

Step 4, encapsulation. A sealing material is coated on the periphery of the box-shaped structure to seal the periphery of the box-shaped structure so that the cathode film 15 and the anode material 14 are not exposed.

In the process of manufacturing the above-mentioned electrochromic display device, the inventors found that there are at least the following problems in the prior art: in the bonding step, because the cathode film and the microcup array need to be accurately aligned, if the alignment is not accurate, The liquid anode material will flow out, resulting in a decrease in the yield of the product, making the alignment process more difficult; in the packaging step, since the side of the cathode film is exposed from the side of the box-shaped structure, it will directly contact with the sealing material contact, thus causing the cathode material to be contaminated by the sealing material, and if there is such an alignment misalignment, it will cause the sealing material to contact the exposed anode material, thereby contaminating the anode material.

Contents of the invention

Embodiments of the present invention provide an electrochromic display device, its preparation method, cathode structure, and microgrid array, which can prevent the cathode material and anode material of the device from being polluted by sealing materials, and can reduce the impact on the device when manufacturing the device. The technological difficulty of the bit process.

In order to achieve the above object, embodiments of the present invention adopt the following technical solutions:

An electrochromic display device, comprising: a microgrid array, a cathode film, a first conductive substrate and a sealing material sequentially formed on a second conductive substrate, each microgrid in the microgrid array is filled with an anode Material, the sealing material is used to seal the cathode film and the anode material; at least one side of the cathode film has a barrier strip, the thickness of the barrier strip in the direction perpendicular to the first conductive substrate The thickness of the cathode film is the same as that of the cathode film; there are three outer walls whose heights exceed the height of the microgrid in the outer walls around the microgrid array, so as to form a drawer-shaped guide groove with a gap above the microgrid, so The above-mentioned protruding height is the same as the thickness of the cathode film, and the inner size of the drawer-shaped guide groove matches the outer peripheral dimension of the cathode film with the barrier strip, so that the cathode film with the barrier strip embedded in the drawer-shaped guide groove, and the position of the blocking strip corresponds to the notch.

A method for preparing an electrochromic display device, comprising: forming a cathode film on a first conductive substrate; forming a barrier strip on at least one side of the cathode film, and the barrier strip is perpendicular to the first conductive The thickness in the substrate direction is the same as the thickness of the cathode film; a microgrid array is formed on the second conductive substrate, and the height of three outer walls in the outer walls around the microgrid array exceeds that of the microgrid array. The height of the microgrid is to form a drawer-shaped guide groove with a gap above the microgrid, the height of the excess is the same as the thickness of the cathode film, and the internal size of the drawer-shaped guide groove is the same as that with the barrier strip The peripheral dimensions of the cathode film are matched; each of the microgrids of the microgrid array is filled with an anode material; the other side of the cathode film is opposite to the side with the barrier strip Aligning the notch of the drawer-shaped guide groove, pushing the cathode film into the drawer-shaped guide groove, so that the first and second conductive substrates, the cathode film and the microgrid array are snapped together A box-like structure; encapsulating said box-like structure with a sealing material.

A cathode structure of an electrochromic display device, comprising a cathode film, and a barrier strip, the barrier strip is formed on at least one side of the cathode film, and the barrier strip is formed in a direction perpendicular to the cathode film The thickness above is the same as that of the cathode film.

A microgrid array of an electrochromic display device, which has a plurality of microgrids with the same height, and the height of three outer walls among the outer walls around the microgrid array exceeds the height of the microgrids, so that the microgrids A drawer-shaped guide groove with notches is formed above the grid.

In the electrochromic display device provided by the embodiment of the present invention, its preparation method, cathode structure, and microgrid array, since the height of three of the outer walls around the microgrid array exceeds the height of the microgrids in the microgrid array, A drawer-shaped guide groove with a notch is formed above the microgrid, and the outer wall of the microgrid does not exceed the position corresponding to the notch, and the height beyond the outer wall is the same as the thickness of the cathode film, and the internal size of the drawer-shaped guide groove is the same as that with The peripheral dimensions of the cathode film of the barrier strip match, so after the cathode film is fastened with the microgrid array, the cathode film and the first conductive substrate can completely seal the anode material. Moreover, the buckling process utilizes the principle of drawers, and a simple method is used to ensure that the anode material is completely sealed, which simplifies the process difficulty of the alignment process.

In addition, since the barrier strip corresponds to the position of the notch on the drawer-shaped guide groove, after the cathode film is fastened with the microgrid array, the barrier strip can seal one side of the cathode film, while the three outer walls of the microgrid array are sealed. Covering the other three sides of the cathode film will not expose the cathode film from the side of the box-shaped structure. Therefore, the sealing material will not contact the cathode and anode materials, and the problem of contamination of the cathode and anode materials by the sealing material will be avoided. .

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained according to these drawings without any creative effort.

FIG. 1 is a cross-sectional view of an existing electrochromic display device;

2 is a perspective view of the cathode part in the electrochromic display device of the present invention;

3 is a perspective view of the anode part in the electrochromic display device of the present invention;

Fig. 4 is a cross-sectional view of the fastening process of the cathode part and the anode part of the electrochromic display device of the present invention.

detailed description

An embodiment of the present invention provides an electrochromic display device, comprising: a microgrid array, a cathode film, a first conductive substrate, and a sealing material sequentially formed on a second conductive substrate, and each microgrid array in the microgrid array The grid is filled with anode material, and the sealing material is used to seal the cathode film and the anode material; at least one side of the cathode film has a barrier strip, and the barrier strip is perpendicular to the first conductive base. The thickness in the material direction is the same as the thickness of the cathode film; the height of three outer walls in the outer walls around the microgrid array exceeds the height of the microgrid, so as to form a drawer with a gap above the microgrid shaped guide groove, the height of the excess is the same as the thickness of the cathode film, and the inner size of the drawer-shaped guide groove matches the outer peripheral dimension of the cathode film with the barrier strip, so that the barrier strip has The cathode film is embedded in the drawer-shaped guide groove, and the blocking strip corresponds to the position of the notch.

An embodiment of the present invention also provides a method for manufacturing an electrochromic display device, comprising: forming a cathode film on a first conductive substrate; forming a barrier strip on at least one side of the cathode film, and the barrier strip is vertical The thickness in the direction of the first conductive substrate is the same as the thickness of the cathode film; a microgrid array is formed on the second conductive substrate, and the height of three of the outer walls around the microgrid array exceeds The height of the micro-grid in the micro-grid array is to form a drawer-shaped guide groove with a gap above the micro-grid array, the height of the excess is the same as the thickness of the cathode film, and the internal dimension of the drawer-shaped guide groove is Matching the peripheral size of the cathode film with the barrier strip; filling the anode material in each of the microgrids of the microgrid array; making the cathode film and the side with the barrier strip The opposite side is aligned with the notch of the drawer-shaped guide groove, and the cathode film is pushed into the drawer-shaped guide groove, so that the first and second conductive substrates, the cathode film and the cathode film The microgrid array is buckled into a box-like structure; the box-like structure is sealed with a sealing material.

An embodiment of the present invention further provides a cathode structure of an electrochromic display device, which includes a cathode film and a barrier bar, the barrier bar is formed on at least one side of the cathode film, and the barrier bar is perpendicular to the The thickness in the direction of the cathode film is the same as the thickness of the cathode film.

The embodiment of the present invention further provides a microgrid array of an electrochromic display device, which has a plurality of microgrids with the same height, and the height of three outer walls among the outer walls around the microgrid array exceeds the height of the microgrids , to form a drawer-shaped guide groove with a gap above the microgrid.

In the electrochromic display device provided by the embodiment of the present invention, its preparation method, cathode structure, and microgrid array, since the height of three of the outer walls around the microgrid array exceeds the height of the microgrids in the microgrid array, A drawer-shaped guide groove with a notch is formed above the microgrid, and the outer wall of the microgrid does not exceed the position corresponding to the notch, and the height beyond the outer wall is the same as the thickness of the cathode film, and the internal size of the drawer-shaped guide groove is the same as that with The peripheral dimensions of the cathode film of the barrier strip match, so after the cathode film is fastened with the microgrid array, the cathode film and the first conductive substrate can completely seal the anode material. Moreover, the buckling process utilizes the principle of drawers, and a simple method is used to ensure that the anode material is completely sealed, which simplifies the process difficulty of the alignment process.

In addition, since the barrier strip corresponds to the position of the notch on the drawer-shaped guide groove, after the cathode film is fastened with the microgrid array, the barrier strip can seal one side of the cathode film, while the three outer walls of the microgrid array are sealed. Covering the other three sides of the cathode film will not expose the cathode film from the side of the box-shaped structure. Therefore, the sealing material will not contact the cathode and anode materials, and the problem of contamination of the cathode and anode materials by the sealing material will be avoided. .

Example 1

An embodiment of the present invention provides an electrochromic display device, and the structure of the device will be described in detail with reference to FIGS. 2 to 4 .

The electrochromic display device includes: a microgrid array 32 , a cathode film 22 , a first conductive substrate 21 and a sealing material (not shown in the figure) sequentially formed on a second conductive substrate 31 . Each microgrid 33 in the microgrid array 32 is filled with an anode material (not shown), and the sealing material is used to seal the cathode film 22 and the anode material; at least one side of the cathode film 22 has Barrier strip 23, the thickness d2 of this barrier strip 23 in the direction perpendicular to the first conductive substrate 21 is the same as the thickness d1 of the cathode film; the height of three outer walls in the outer walls 34 around the micro grid array 32 exceeds The height of the microgrid 33 is such that a drawer-shaped guide groove 35 with a gap is formed above the microgrid 33 . Wherein, the height d3 that the outer wall 34 exceeds is the same as the thickness d2 of the cathode film, and the internal dimension (width W2, length L2) of the drawer-shaped guide groove is the same as the outer circumference dimension (width W1, length L1) of the cathode film 22 with the barrier bar 23. ) match, so that the cathode film 22 with the barrier strip 23 is embedded in the drawer-shaped guide groove 35, and the barrier strip 23 corresponds to the position of the notch.

In the above electrochromic display device, the barrier strips 23 may be made of, but not limited to, radiation-cured materials, and the microgrid arrays may be made of, but not limited to, radiation-cured materials. The ratio of the thickness of the cathode film to the height of the microgrid may be 1:3-1:10, preferably 1:5-1:8.

In addition, the sealing material in the above-mentioned electrochromic display device may be ultraviolet curing glue, or low temperature epoxy resin glue.

Because the height of three of the outer walls around the microgrid array exceeds the height of the microgrids in the microgrid array, a drawer-like guide groove with a gap is formed above the microgrid, and the outer wall that does not exceed the microgrid corresponds to The position of the gap, and the height beyond the outer wall is the same as the thickness of the cathode film, and the internal size of the drawer-shaped guide groove matches the outer peripheral size of the cathode film with the barrier strip, so after the cathode film and the microgrid array are fastened, the cathode film and the The first conductive substrate completely encapsulates the anode material.

In addition, since the barrier strip corresponds to the position of the notch on the drawer-shaped guide groove, after the cathode film is fastened with the microgrid array, the barrier strip can seal one side of the cathode film, while the three outer walls of the microgrid array are sealed. Covering the other three sides of the cathode film will not expose the cathode film from the side of the box-shaped structure. Therefore, the sealing material will not contact the cathode and anode materials, and the problem of contamination of the cathode and anode materials by the sealing material will be avoided. .

Example 2

This embodiment provides a method for manufacturing an electrochromic display device, as shown in FIGS. 2-4 , the method includes the following steps.

Step 1, forming a cathode thin film 22 on the first conductive substrate 21 .

Step 2, forming barrier strips 23 on the side of the cathode film 22 .

Specifically, as shown in FIG. 2, at least one side of the cathode film 22 is coated with a radiation-curable material and photocured to form a barrier strip 23 on the at least one side of the cathode film 22, so The thickness d2 of the barrier strip 23 in the direction perpendicular to the first conductive substrate 21 is the same as the thickness d1 of the cathode film 22 .

It should be noted that the number of barrier strips 23 is not limited to one as shown in FIG. After the cathode film is fastened with the microgrid array described below, the added barrier strips can better prevent the anode and cathode materials from being polluted by the sealing material.

Step 3, forming a microgrid array 32 with drawer-shaped guide grooves 35 .

Specifically, as shown in FIG. 3 , a microgrid array 32 is formed on the second conductive substrate 31, and the height of three outer walls 34 exceeds that of the microgrid array 32 in the outer walls 34 around the microgrid array 32. The height of the microgrid 33 is to form a drawer-shaped guide groove 35 with a gap above the microgrid 33, the height d3 of the excess is the same as the thickness d1 of the cathode film 22, and the inside of the drawer-shaped guide groove 35 The dimensions (width W2, length L2) match the outer peripheral dimensions (width W1, length L1) of the cathode film 22 with the barrier strips 23. That is, the cathode film 22 with the barrier strip 23 can just be accommodated in the drawer-shaped guide groove 35 with the gap.

It should be noted that the number of micro cells is not limited to 4 as shown in FIG. 3 , and different numbers can be set according to different process requirements.

Step 4, filling anode material in each of the microgrids 33 of the microgrid array 32 .

Step 5, buckle the synthesis box.

Specifically, as shown in Figure 4, the other side of the cathode film 22, opposite to the side with the barrier strip 23, is aligned with the notch of the drawer-shaped guide groove 35, and the cathode film 22 is pushed into the drawer-shaped guide groove 35, so that the first conductive substrate 21, the second conductive substrate 31, the cathode film 22 and the microgrid array 32 are buckled into a box-like structure.

Step 6, sealing the box-shaped structure with a sealing material to form an electrochromic display device.

In this embodiment, since the height of three outer walls 34 in the outer walls 34 around the microgrid array 32 exceeds the height of the microgrids in the microgrid array 32, a drawer-shaped guide groove 35 with a gap is formed above the microgrid array. The position corresponding to the notch on the outer wall that does not exceed the microgrid, so in the step of buckling the box, you only need to align the side of the cathode film 22 corresponding to the notch with the notch, and then push the cathode film 22 like a drawer. into the drawer-shaped guide groove 35, the snap-fit of the cathode film 22 and the microgrid array 32 can be completed; (width W2, long L2) match with the peripheral size of the cathode film 22 having barrier bar 23 (width W1, long L1), so after the cathode film 22 is fastened with the microgrid array 32, the cathode film 22 and the first conductive substrate 21 can completely seal the anode material. This embodiment utilizes the drawer principle to ensure that the anode material is completely sealed by a simple method, which simplifies the technical difficulty of the alignment process.

In addition, because in the step of buckling the synthetic box, the other side opposite to the side with the barrier strip 23 on the cathode film 22 is aligned with the notch, so after the cathode film 22 and the microgrid array 32 are buckled together, the barrier strip 23 can seal one side of the cathode film 22, and the three outer walls 34 higher than the microgrid array 32 seal the other three sides of the cathode film 22, so that the cathode film 22 will not be exposed from the side of the box-shaped structure. Therefore, in the subsequent packaging step, the sealing material will not contact the cathode and anode materials, thus avoiding the problem that the cathode and anode materials are polluted by the sealing material.

Example 3

This embodiment provides a method for manufacturing an electrochromic display device, and the method includes the following steps.

Step 1, forming a cathode thin film on the first conductive substrate. This step specifically includes: A) forming a film-forming groove with a thickness of 20-40 μm on the first conductive substrate; B) filling the film-forming groove with a cathode material by screen printing, doctor blade coating or spin coating; C) Bake the first conductive substrate for 30 minutes at an ambient temperature of 30°C to 50°C, preferably 45°C, to form a cathode film with a thickness of 5 to 20 μm, preferably 10 to 15 μm; D) remove the film-forming groove.

Step 2, forming barrier bars on the side of the cathode film.

Specifically, at least one side of the cathode film is coated with a radiation-curable material and photocured to form a barrier strip on the at least one side of the cathode film, and the barrier strip is perpendicular to the direction of the first conductive substrate. The thickness is the same as that of the cathode film.

Step 3, forming a microgrid array with drawer-shaped guide grooves.

Specifically, this step includes: A) coating a radiation-cured material on the second conductive substrate; B) light-curing the radiation-cured material through a grayscale mask; C) cleaning the uncured radiation-cured material so that A microgrid array is formed on the second conductive substrate. Among the outer walls around the microgrid array, the height of three outer walls exceeds the height of the microgrids in the microgrid array, so as to form a drawer-shaped guide groove with a gap above the microgrid array, and the excess height is equal to the thickness of the cathode film. Likewise, the inner dimensions of the drawer-shaped channel match the outer peripheral dimensions of the cathode film with the barrier strips.

In addition, the ratio of the thickness of the cathode film to the height of the microgrid can be 1:3 to 1:10, preferably 1:5 to 1:8, so that the electrochromic display device formed by the above method has better display performance .

Step 4, filling the anode material in each microgrid of the microgrid array by scraping or filling.

Step 5. In a vacuum environment with an ambient temperature of 45°C, use infrared detection to align the other side of the cathode film opposite to the side with the barrier strip with the notch of the drawer-shaped guide groove Pushing the cathode film into the drawer-shaped guide groove, so that the first and second conductive substrates, the cathode film and the microgrid array are buckled into a box-like structure.

Step 6, encapsulating the box-shaped structure with a sealing material to form an electrochromic display device. Wherein, the sealing material may be but not limited to ultraviolet curing glue or low temperature epoxy resin glue.

In this embodiment, because the height of three exterior walls in the outer walls around the microgrid array exceeds the height of the microgrids in the microgrid array, a drawer-like guide groove with gaps is formed above the microgrids, which does not exceed the height of the microgrids. The outer wall corresponds to the position of the notch, so in the step of buckling the synthesis box, you only need to align the side of the cathode film corresponding to the notch with the notch, and then push the cathode film into the drawer-shaped guide groove like a drawer. The fastening of the cathode film and the microgrid array can be completed; and because the height of the above-mentioned outer wall is the same as the thickness of the cathode film, and the internal size of the drawer-shaped guide groove matches the outer peripheral size of the cathode film with the barrier strip, the cathode After the film is buckled with the microgrid array, the cathode film and the first conductive substrate can completely seal the anode material. This embodiment utilizes the drawer principle to ensure that the anode material is completely sealed by a simple method, which simplifies the technical difficulty of the alignment process.

In addition, because in the step of buckling the synthesis box, the other side of the cathode film opposite to the side with the barrier strip is aligned with the notch, so after the cathode film is buckled with the microgrid array, the barrier strip can seal the cathode film. One side of the film, and the three outer walls of the microgrid array seal the other three sides of the cathode film, so that the cathode film will not be exposed from the side of the box-shaped structure, so that in the subsequent packaging step, the sealing material The cathode and anode materials will not be contacted, so the problem of the cathode and anode materials being polluted by the sealing material is avoided.

It should be noted that the first and second conductive substrates in the above embodiments can be transparent conductive glass, or a structure in which a transparent insulating substrate and ITO are bonded together.

Example 4

This embodiment provides a cathode structure of an electrochromic display device, as shown in FIG. 2 , including a cathode film 22 and a barrier strip 23 formed on at least one side of the cathode film 22, And the thickness d2 of the barrier strip 23 in the direction perpendicular to the cathode film 22 is the same as the thickness d1 of the cathode film 22 .

The present embodiment also provides a microgrid array 32 of an electrochromic display device, as shown in FIG. The height of the outer wall 34 exceeds the height of the microgrid 33 to form a drawer-shaped guide groove 35 with a gap above the microgrid 33 .

The cathode structure, the microgrid array and their preparation methods of the above-mentioned electrochromic display device have been described in detail in Embodiment 1 to Embodiment 3, and will not be repeated here.

The embodiments of the present invention are mainly used in electronic paper, portable electronic products, and the like.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (18)

1. An electrochromic display device, comprising: a microgrid array, a cathode film, a first conductive substrate and a sealing material successively formed on the second conductive substrate, filling in each microgrid in the microgrid array There is an anode material, and the sealing material is used to seal the cathode film and the anode material, characterized in that, One side of the cathode film has a barrier strip, and the thickness of the barrier strip in a direction perpendicular to the first conductive substrate is the same as the thickness of the cathode film; The microgrid array has a plurality of microgrids with the same height, and the height of three outer walls in the outer walls around the microgrid array exceeds the height of the microgrid, so as to form a gap with gaps above the microgrid array. The drawer-shaped guide groove, the height of the excess is the same as the thickness of the cathode film, and the inner size of the drawer-shaped guide groove matches the outer peripheral dimension of the cathode film with the barrier strip, so that the barrier strip has the The cathode film of the strip is embedded in the drawer-shaped guide groove, and the blocking strip corresponds to the position of the notch. 2. The electrochromic display device according to claim 1, wherein the barrier ribs are made of radiation curable material. 3. The electrochromic display device according to claim 1, wherein the microgrid array is made of radiation-cured material. 4 . The electrochromic display device according to claim 1 , wherein the ratio of the thickness of the cathode film to the height of the microgrid is 1:3˜1:10. 5 . The electrochromic display device according to claim 4 , wherein the ratio of the thickness of the cathode film to the height of the microgrid is 1:5˜1:8. 6 . The electrochromic display device according to claim 1 , wherein the sealing material is ultraviolet curing glue or low temperature epoxy resin glue. 7. A method for preparing an electrochromic display device, comprising: forming a cathode film on the first conductive substrate; forming a barrier strip on one side of the cathode film, the thickness of the barrier strip in a direction perpendicular to the first conductive substrate is the same as the thickness of the cathode film; A microgrid array is formed on the second conductive substrate, the microgrid array has a plurality of microgrids with the same height, and the height of three outer walls in the outer walls around the microgrid array exceeds that of the microgrid array The height of the microgrid is to form a drawer-shaped guide groove with a gap above the microgrid, the height of the excess is the same as the thickness of the cathode film, and the internal size of the drawer-shaped guide groove is the same as that with the barrier strip The peripheral dimensions of the cathode film are matched; Filling an anode material in each of the microgrids of the microgrid array; Make the other side of the cathode film opposite to the side with the blocking strip aligned with the notch of the drawer-shaped guide groove, push the cathode film into the drawer-shaped guide groove, so that The first and second conductive substrates, the cathode film and the microgrid array are combined into a box-like structure; The box-like structure is encapsulated with a sealing material. 8. The method according to claim 7, wherein said forming a barrier strip on one side of said cathode film comprises: Coating a first radiation curable material on one side of the cathode film and performing photocuring to form the barrier strips on one side of the cathode film. 9. The method according to claim 7, wherein said forming a microgrid array on the second conductive substrate comprises: coating a second radiation curable material on the second conductive substrate; Light-curing the second radiation-curable material through a grayscale mask; Cleaning the uncured second radiation curable material to form the microgrid array on the second conductive substrate. 10. method according to claim 7, is characterized in that, described filling anode material in each described microgrid of described microgrid array, comprises: The anode material is filled in each microgrid of the microgrid array by scraping or filling. 11. The method according to claim 7, wherein said forming a cathode film on the first conductive substrate comprises: forming a film-forming groove with a thickness of 20-40 μm on the first conductive substrate; Filling the cathode material in the film-forming tank by screen printing, scraping or spin coating; Baking the first conductive substrate for 30 minutes at an ambient temperature of 30°C-50°C to form a cathode film with a thickness of 5-20 μm; The film-forming groove is removed. 12. The method according to claim 11, characterized in that, at an ambient temperature of 30° C. to 50° C., the first conductive substrate is baked for 30 minutes to form a cathode film with a thickness of 5 to 20 μm, include: At an ambient temperature of 45° C., the first conductive substrate is baked for 30 minutes to form a cathode film with a thickness of 5-20 μm. 13. The method according to claim 11, characterized in that the thickness of the cathode film is 10-15 μm. 14. The method according to claim 7, wherein the other side of the cathode film, which is opposite to the side with the barrier strip, is aligned with the notch of the drawer-shaped guide groove, include: The other side of the cathode film opposite to the side with the barrier strip is aligned with the notch of the drawer-shaped guide groove by means of infrared detection. 15. The method according to claim 7, wherein the other side of the cathode film opposite to the side with the barrier strip is aligned with the notch of the drawer-shaped guide groove, Pushing the cathode film into the drawer-shaped guide groove, so that the first and second conductive substrates, the cathode film and the microgrid array are buckled into a box-like structure, including: Under the condition of vacuum environment and ambient temperature of 45°C, align the other side of the cathode film opposite to the side with the barrier bar with the notch of the drawer-shaped guide groove, and place the The cathode film is pushed into the drawer-shaped guide groove, so that the first and second conductive substrates, the cathode film and the microgrid array are buckled into a box-like structure. 16. The method according to any one of claims 7-15, characterized in that the ratio of the thickness of the cathode film to the height of the microgrid is 1:3-1:10. 17. The method according to claim 16, characterized in that the ratio of the thickness of the cathode film to the height of the microgrid is 1:5˜1:8. 18. The method according to any one of claims 7-15, wherein the sealing material is ultraviolet curing glue or low temperature epoxy resin glue.