KR-20260062139-A - SEPARATOR FOR ELECTROCHEMICAL DEVICE, ELECTROCHEMICAL DEVICE

KR20260062139AKR 20260062139 AKR20260062139 AKR 20260062139AKR-20260062139-A

Abstract

One embodiment of the present invention comprises a separator body and a protective layer coated on the surface of the separator body, wherein the protective layer comprises Mn-Co oxide, and wherein the region including the inner surface in contact with the surface of the separator body in the protective layer is called the inner region and the region including the outer surface is called the outer region, the Mn-Co oxide provides a separator for an electrochemical device in which the Mn content in the inner region is higher than the Mn content in the outer region.

Inventors

양정승
김동진
박중덕

Assignees

삼성전기주식회사

Dates

Publication Date: 20260507
Application Date: 20241025

Claims (16)

Separator plate body; and It includes a protective layer coated on the surface of the above-mentioned separator body; and The above protective layer comprises Mn-Co oxide, and A separator for an electrochemical device in which the Mn-Co oxide is a region including an inner surface in contact with the surface of the separator body in the above protective layer is called an inner region, and the region including an outer surface is called an outer region, wherein the Mn-Co oxide has a higher Mn content in the inner region than in the outer region.
In paragraph 1, The above Mn-Co oxide is a separator for an electrochemical device that shows a tendency for the Mn content to decrease as it moves from the inner region to the outer region.
In paragraph 2, The above Mn-Co oxide is a separator for an electrochemical device that shows a tendency for the Co content to decrease as it moves from the outer region to the inner region.
In paragraph 3, A separator for an electrochemical device in which the degree of decrease in Mn content from the inner region to the outer region in the above Mn-Co oxide is greater than the degree of decrease in Co content from the outer region to the inner region.
In paragraph 1, The above internal region is a separator for an electrochemical device comprising Mn oxide that substantially does not contain Co.
In paragraph 5, The above Mn oxide is a separator for an electrochemical device formed on the inner surface.
In paragraph 1, The above outer region is a separator for an electrochemical device comprising Co oxide that does not substantially contain Mn.
In Paragraph 7, The above Co oxide is a separator for an electrochemical device formed on the outer surface.
In paragraph 1, A separator for an electrochemical device having a protective layer thickness of 2 μm to 10 μm.
In paragraph 1, The thickness of the inner region is 1/10 to 1/5 of the thickness of the protective layer, and A separator for an electrochemical device in which the thickness of the outer region is 1/10 to 1/5 of the thickness of the protective layer.
In paragraph 1, The above protective layer is a separator for an electrochemical device formed on two main surfaces facing each other in the thickness direction on the separator body and on a side connecting the two main surfaces.
In paragraph 1, The above protective layer is formed on one of the two main surfaces facing each other in the thickness direction on the separator body, and A separator for an electrochemical device that is not formed on the remaining main surface of the two main surfaces and on the side connecting the two main surfaces.
In paragraph 1, The above protective layer is formed on two opposing main surfaces in the thickness direction of the separator body, and A separator for an electrochemical device that is not formed on the side connecting the two main surfaces above.
Multiple separator plates; and An electrochemical cell comprising a fuel electrode, an air electrode, and an electrolyte disposed between the plurality of separator plates; At least one of the plurality of separator plates above is, It includes a separator body and a protective layer coated on the surface of the separator body, and The above protective layer comprises Mn-Co oxide, and An electrochemical device in which the Mn-Co oxide is a region including an inner surface in contact with the surface of the separator body in the above protective layer is called an inner region, and the region including an outer surface is called an outer region, wherein the Mn-Co oxide has a higher Mn content in the inner region than in the outer region.
In Paragraph 14, An electrochemical device in which, among the plurality of separators, a separator disposed adjacent to the air electrode, the protective layer is formed on the main surface facing the air electrode among at least two main surfaces facing each other in the thickness direction from the separator body.
In Paragraph 14, In the separator plate positioned adjacent to the air electrode among the plurality of separator plates above, The above protective layer is not formed on the remaining main surface of the two main surfaces and on the side connecting the two main surfaces in the separator body of the electrochemical device.

Description

Separator for Electrochemical Device and Electrochemical Device The present invention relates to a separator for an electrochemical device and an electrochemical device. Electrochemical devices include fuel cells that generate electrical energy by electrochemically reacting a fuel (hydrogen) and an oxidant (pure oxygen or oxygen from the air), and electrolysis cells that generate hydrogen and oxygen through the electrolysis of water. As an example of such electrochemical devices, solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs) include a cell composed of an air electrode, a fuel electrode, and a solid electrolyte having oxygen ion conductivity, wherein the cell can be referred to as a solid oxide cell. Solid oxide cells produce electrical energy through electrochemical reactions or produce hydrogen by electrolyzing water through the reverse reaction of solid oxide fuel cells. In addition to this, other types of fuel cells or electrolysis cells, such as phosphoric acid fuel cells (PAFCs), alkaline fuel cells (AFCs), polymer electrolyte fuel cells (PEMFCs), and direct methanol fuel cells (DMFCs), are also used as forms of electrochemical devices. When electrochemical devices, such as solid oxide cells, are operated at high temperatures for extended periods, the characteristics of the device may deteriorate due to the diffusion of unintended substances, such as elements contained in the separator. Therefore, there have been attempts in the field to reduce the performance degradation of electrochemical devices. FIGS. 1 and FIGS. 2 schematically illustrate the external appearance of a separator for an electrochemical device according to one embodiment of the present invention and correspond to a perspective view and a cross-sectional view, respectively. Figure 3 shows an enlarged view of area A in Figure 2. Figures 4 to 7 are graphs showing the relative content of Mn and Co in the Mn-Co oxide of the protective layer according to location. Figures 8 and 9 show an example of a process for forming a protective layer of a separator for an electrochemical device. FIGS. 10 to 12 are cross-sectional views showing a separator for an electrochemical device according to a modified embodiment. FIG. 13 shows a water electrolysis device with a separator plate applied according to an embodiment of the present invention. Embodiments of the present invention will be described below with reference to specific embodiments and the attached drawings. However, embodiments of the present invention may be modified in various different forms, and the scope of the present invention is not limited to the embodiments described below. Furthermore, embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. Accordingly, the shapes and sizes of elements in the drawings may be exaggerated for clearer explanation, and elements indicated by the same reference numerals in the drawings are the same elements. Furthermore, in order to clearly explain the invention in the drawings, parts irrelevant to the explanation are omitted, and thicknesses are enlarged to clearly represent various layers and regions. Components with identical functions within the scope of the same concept are described using the same reference numerals. Moreover, throughout the specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. FIGS. 1 and 2 schematically illustrate the external appearance of a separator for an electrochemical device according to one embodiment of the present invention and correspond to a perspective view and a plan view, respectively. FIG. 3 is an enlarged view of area A in FIG. 2. FIGS. 4 to 7 are graphs showing the relative content of Mn and Co in the Mn-Co oxide of the protective layer according to location. First, referring to FIGS. 1 to 3, a separator plate (100, hereinafter referred to as 'separator plate for electrochemical device' or 'separator plate') according to one embodiment of the present invention comprises a separator plate body (101) and a protective layer (110). Herein, the protective layer (110) functions to prevent the deterioration of the cell by preventing a component (e.g., Cr) contained in the separator plate body (101) from diffusing into the cell during the operation of the electrochemical device. To this end, the protective layer (110) comprises Mn-Co oxide, wherein the Mn content in the inner region (110A) of the protective layer (110) is higher than the Mn content in the outer region (110B). By including Mn-Co oxide with such content conditions, the protective layer (110) can be implemented to have a dense and sufficient thickness, and can effectively prevent the element of the separator plate body (101) from diffusing into the cell. In addition, the protective layer (110) contains Mn-