Oxygen sensor, manufacturing method thereof, engine and vehicle
By designing the end surface design of the stacked electrolyte layer and diffusion barrier structure in the oxygen sensor, the problem of gas channel deformation during the stacking molding of the oxygen sensor is solved, and higher detection accuracy and yield are achieved.
Patent Information
- Application Number
- CN202410128483.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-29
- Publication Date
- 2025-07-29
AI Technical Summary
During the stacking and forming process of the oxygen sensor, the gas channel to be tested is easily extruded and deformed, resulting in damage to the diffusion barrier structure and affecting the detection accuracy.
An oxygen sensor is designed, including a stacked first electrolyte layer and a second electrolyte layer. The diffusion barrier structure is arranged through the first electrolyte layer and in communication with the detection cavity. The end surface of the diffusion barrier structure is flush or protruding from the surface of the first electrolyte layer to avoid the formation of the gas channel to be tested and enhance the support structure.
The deformation of the gas channel to be tested and the rupture of the diffusion barrier structure is avoided, the detection accuracy and manufacturing yield are improved, and the manufacturing difficulty is reduced.
Smart Images
Figure CN120385732A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of gas sensors, and more particularly to an oxygen sensor and a manufacturing method thereof, an engine, and a vehicle. Background Art
[0002] An oxygen sensor can convert the oxygen concentration in a gas to be measured into an electrical signal readable by a computer, and plays a crucial role in the fields of automobiles, medical treatment, industry, and environmental monitoring. For example, an oxygen sensor can be applied to an engine to detect the oxygen concentration in the engine exhaust. In the related art, during the lamination molding process of the oxygen sensor, the gas passage to be measured of the oxygen sensor is easily squeezed and deformed, thereby damaging the diffusion barrier structure and ultimately affecting the detection accuracy. Summary of the Invention
[0003] The present application is proposed to solve at least one of the above problems. According to a first aspect of the present application, there is provided an oxygen sensor, including: a stacked first electrolyte layer and second electrolyte layer, wherein a detection cavity is provided in the second electrolyte layer; the oxygen sensor further includes: a diffusion barrier structure, at least part of the diffusion barrier structure penetrates through the first electrolyte layer, and the diffusion barrier structure communicates with the detection cavity; wherein, a first end face is provided on a side of the diffusion barrier structure away from the second electrolyte layer, and the first end face is flush with or protrudes from a surface of the first electrolyte layer facing away from the second electrolyte layer.
[0004] In an embodiment of the present application, the diffusion barrier structure further extends into the detection cavity.
[0005] In an embodiment of the present application, the detection cavity has a first cavity wall and a second cavity wall opposite in position, wherein the first cavity wall is located on a surface of the first electrolyte layer facing the second electrolyte layer; a second end face is further provided on the diffusion barrier structure, and the second end face abuts against the second cavity wall of the detection cavity.
[0006] In an embodiment of the present application, the diffusion barrier structure is a diffusion barrier column.
[0007] In an embodiment of the present application, the extending direction of the diffusion barrier column is parallel to the lamination direction of the first electrolyte layer and the second electrolyte layer.
[0008] In an embodiment of the present application, a test electrode is provided on a surface of the first electrolyte layer facing away from the second electrolyte layer, a common electrode is provided in the detection cavity, and the pump cell of the oxygen sensor includes the test electrode and the common electrode.
[0009] In one embodiment of the present application, the oxygen sensor further includes a reference chamber for accommodating a reference gas. A reference electrode is disposed in the reference chamber. The Nernst cell of the oxygen sensor includes the reference electrode and the common electrode.
[0010] In one embodiment of the present application, the oxygen sensor further includes: a third electrolyte layer and a fourth electrolyte layer. The third electrolyte layer is laminated on the surface of the second electrolyte layer facing away from the first electrolyte layer. The fourth electrolyte layer is laminated on the surface of the third electrolyte layer facing away from the second electrolyte layer. The reference chamber is disposed in the fourth electrolyte layer. Wherein, the reference chamber has a third chamber wall and a fourth chamber wall opposite to each other. The third chamber wall is located on the surface of the third electrolyte layer facing the fourth electrolyte layer, and the reference electrode is disposed on the third chamber wall.
[0011] In one embodiment of the present application, the oxygen sensor further includes: a heating layer for heating. The heating layer is laminated on the surface of the fourth electrolyte layer facing away from the third electrolyte layer. Wherein, the total thickness of the heating layer and the fourth electrolyte layer is equal to the total thickness of the first electrolyte layer, the second electrolyte layer and the third electrolyte layer.
[0012] According to a second aspect of the present application, there is also provided a method for manufacturing an oxygen sensor. The manufacturing method includes: forming a detection chamber in a second electrolyte layer; laminating a first electrolyte layer and the second electrolyte layer; forming a diffusion barrier structure at least partially penetrating through the first electrolyte layer. The diffusion barrier structure communicates with the detection chamber. Wherein, one side of the diffusion barrier structure away from the second electrolyte layer has a first end face, and the first end face is flush with or protrudes from the surface of the first electrolyte layer facing away from the second electrolyte layer.
[0013] In one embodiment of the present application, the manufacturing method further includes: forming a through hole in the first electrolyte layer, and after laminating the first electrolyte layer and the second electrolyte layer, the through hole communicates with the detection chamber. The step of forming a diffusion barrier structure at least partially penetrating through the first electrolyte layer includes: forming a diffusion barrier structure at least filling in the through hole.
[0014] According to a third aspect of the present application, there is also provided an engine, which includes: any one of the above-mentioned oxygen sensors.
[0015] According to a fourth aspect of the present application, there is also provided a vehicle, which includes: any one of the above-mentioned oxygen sensors, or any one of the above-mentioned engines.
[0016] According to the oxygen sensor, manufacturing method thereof, engine, and vehicle provided by the embodiments of the present application, by making the first end face of the diffusion barrier structure flush with or protruding from the surface of the first electrolyte layer facing away from the second electrolyte layer, the gas to be measured enters the detection cavity through the diffusion barrier structure. Compared with the related art, the present application does not need to provide a gas channel to be measured, avoiding the situation that the gas channel to be measured is squeezed and deformed, and also avoiding the situation that the diffusion barrier structure is squeezed and damaged by the deformed gas channel, thereby improving the detection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can also obtain other drawings based on these drawings without creative efforts.
[0018] Figure 1 is a schematic structural diagram of a wide-range oxygen sensor with a "longitudinally embedded" diffusion barrier unit in the related art;
[0019] Figure 2 is a schematic structural diagram of a wide-range oxygen sensor with a "horizontally penetrating" diffusion barrier unit in the related art;
[0020] Figure 3 is a schematic cross-sectional structural diagram of an oxygen sensor shown in an embodiment of the present invention;
[0021] Figure 4 is a schematic longitudinal-sectional structural diagram of an oxygen sensor shown in an embodiment of the present invention.
[0022] Figures 1 to 2 The reference numerals in
[0023] 1 - Gas channel to be measured 2 - Diffusion barrier unit 3 - Detection cavity
[0024] Figures 3 to 4 The reference numerals in
[0025] 101 - Upper surface of the oxygen sensor 102 - Lower surface of the oxygen sensor
[0026] 11 - First electrolyte layer 12 - Second electrolyte layer 13 - Third electrolyte layer
[0027] 14 - Fourth electrolyte layer 15 - Fifth electrolyte layer 16 - Sixth electrolyte layer
[0028] 20 - Diffusion barrier structure 21 - First end face 22 - Second end face
[0029] 30 - Detection cavity 31 - First cavity wall 32 - Second cavity wall
[0030] 40 - Reference cavity 41 - Third cavity wall 42 - Fourth cavity wall
[0031] 51 - First common electrode 52 - Second common electrode 53 - Test electrode
[0032] 54 - Reference electrode 55 - Heating electrode 61 - Electrode protection layer 62 - Insulating layer Detailed implementation manners
[0033] In order to make the objectives, technical solutions and advantages of the present invention more apparent, exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments of the present invention. It should be understood that the present invention is not limited by the exemplary embodiments described herein. Based on the embodiments of the present invention described herein, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present invention.
[0034] In the following description, numerous specific details are given to provide a more thorough understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without one or more of these details. In other instances, in order to avoid confusion with the present invention, some well - known technical features are not described.
[0035] It should be understood that the present invention can be implemented in different forms and should not be construed as limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the present invention to those skilled in the art.
[0036] The purpose of the terms used herein is only to describe specific embodiments and is not a limitation of the present invention. When used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, identify the presence of the described features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups. When used herein, the term "and / or" includes any and all combinations of the related listed items.
[0037] To thoroughly understand the present invention, detailed structures will be presented in the following description to illustrate the technical solutions proposed by the present invention. The alternative embodiments of the present invention are described in detail as follows. However, in addition to these detailed descriptions, the present invention can also have other implementation manners.
[0038] In the structure of a wide - area oxygen sensor, the diffusion barrier unit is a key component for forming the limiting pump current. Refer to Figure 1 and Figure 2 , the diffusion barrier unit 2 of the wide - area oxygen sensor can be classified into two types according to its shape. One is the "longitudinally embedded type", and the other is the "horizontally penetrating type". That is, the diffusion barrier unit 2 mainly includes the "longitudinally embedded" structure and the "horizontally penetrating" structure. Here, the horizontal direction refers to the direction parallel to the width direction of the oxygen sensor, such as the horizontal direction in Figure 1 and Figure 2 is the horizontal direction; the longitudinal direction here refers to the direction perpendicular to the width direction of the oxygen sensor, such as the vertical direction in Figure 1 and Figure 2 is the longitudinal direction.
[0039] Refer to Figure 1 , when the diffusion barrier unit 2 adopts the "longitudinally embedded" structure, a test gas channel 1 is formed above the diffusion barrier unit 2. The test gas enters the diffusion barrier unit 2 after passing through the test gas channel 1, and then enters the detection chamber 3 through the diffusion barrier unit 2, and then the oxygen content is detected. The result of such a design is that the test gas channel 1 must be formed. When the test gas channel 1 is under pressure during the subsequent lamination and molding process, it will deform, and even cause the diffusion barrier unit 2 to be unevenly squeezed or sheared and cracked, affecting the detection accuracy.
[0040] Refer to Figure 2 , when the diffusion barrier unit 2 adopts the "horizontally penetrating" structure design, the diffusion barrier unit 2 horizontally penetrates the oxygen sensor, that is, the horizontal outer edge of the diffusion barrier unit 2 is flush with the horizontal outer edge of the oxygen sensor. The test gas enters the diffusion barrier unit 2 through the two side edges of the diffusion barrier unit 2, and then enters the detection chamber 3 through the diffusion barrier unit 2, and then the oxygen content is detected. This structural design does not require the formation of a test gas channel 1. However, since the diffusion barrier unit 2 is screen - printed onto the solid electrolyte layer through a screen printing stencil, its strength is low; and there is no solid electrolyte body as a support in the horizontal direction of the diffusion barrier unit 2, so the diffusion barrier unit 2 will directly bear the pressure during the lamination and molding process. This will cause the diffusion barrier unit to be longitudinally compressed, thereby changing its overall design structure, even changing the pore structure and morphology, and also reducing its porosity, thus affecting the entry of the test gas and the detection accuracy.
[0041] It can be seen that the defects brought by the above two types of structural designs are that the diffusion barrier unit 2 is prone to cracks due to uneven extrusion, or the overall structure of the diffusion barrier unit 2 is prone to being extruded and deformed, thus affecting the detection accuracy. To solve the above - mentioned technical problems, the following embodiments are given in this application.
[0042] The following will describe in detail some embodiments of the present invention with reference to the accompanying drawings. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.
[0043] First, the application scenario of the oxygen sensor illustrated in the examples of the present application will be introduced. The oxygen sensor is used to measure the oxygen concentration in the gas to be measured. The oxygen sensor can be a wide-range oxygen sensor.
[0044] Reference Figure 3 and Figure 4 According to the embodiments of the present application, an oxygen sensor is provided, which includes: a stacked first electrolyte layer 11 and a second electrolyte layer 12. Among them, a detection cavity 30 is provided in the second electrolyte layer 12; the oxygen sensor further includes: a diffusion barrier structure 20, the diffusion barrier structure 20 at least partially penetrates through the first electrolyte layer 11, and the diffusion barrier structure 20 communicates with the detection cavity 30; wherein, the side of the diffusion barrier structure 20 away from the second electrolyte layer 12 has a first end face 21, and the first end face 21 is flush with or protrudes from the surface of the first electrolyte layer 11 facing away from the second electrolyte layer 12.
[0045] In the above solution, by making the first end face 21 of the diffusion barrier structure 20 flush with or protrude from the surface of the first electrolyte layer 11 facing away from the second electrolyte layer 12, the gas to be measured enters the detection cavity 30 through the diffusion barrier structure 20. Compared with the related art, the present application does not need to provide a gas passage for the gas to be measured, avoiding the situation that the gas passage for the gas to be measured is squeezed and deformed, and also avoiding the situation that the diffusion barrier structure 20 is squeezed and damaged by the deformed gas passage, thereby improving the detection accuracy. The following will introduce the above-mentioned various structures in detail with reference to the accompanying drawings.
[0046] When setting the first electrolyte layer 11 and the second electrolyte layer 12, reference Figure 3 and Figure 4 shows that the material of the first electrolyte layer 11 can be a solid electrolyte layer. The material of the second electrolyte layer 12 can also be a solid electrolyte layer. The first electrolyte layer 11 has two opposite upper and lower surfaces, and the second electrolyte layer 12 has two opposite upper and lower surfaces. One surface of the first electrolyte layer 11 is stacked on one surface of the second electrolyte layer 12, so as to realize the stacked design of the first electrolyte layer 11 and the second electrolyte layer 12. The stacking direction of the first electrolyte layer 11 and the second electrolyte layer 12 is perpendicular to the surfaces of the first electrolyte layer 11 and the second electrolyte layer 12. For example, Figure 3 and Figure 4 the vertical direction in is the stacking direction of the first electrolyte layer 11 and the second electrolyte layer 12.
[0047] A detection cavity 30 is provided in the second electrolyte layer 12. Reference Figure 3 and Figure 4, the detection chamber 30 is used to introduce the gas to be measured to detect the oxygen content of the gas to be measured. The shape of the detection chamber 30 can be, such as but not limited to, a circular chamber, a square chamber, etc. Exemplarily, the detection chamber 30 can penetrate through two opposite surfaces of the second electrolyte layer 12 in the up and down directions. For example, the detection chamber 30 has a first chamber wall 31 and a second chamber wall 32 which are opposite to each other, wherein the first chamber wall 31 can be located on the surface of the first electrolyte layer 11 facing the second electrolyte layer 12, and the second chamber wall 32 can be located on the surface of another electrolyte layer laminated on the second electrolyte layer 12. Exemplarily, a third electrolyte layer 13 is laminated on the surface of the second electrolyte layer 12 facing away from the first electrolyte layer 11, then the second chamber wall 32 is the surface of the third electrolyte layer 13 facing the second electrolyte layer 12 on one side.
[0048] Reference Figure 3 And Figure 4 , when the diffusion barrier structure 20 is provided, the diffusion barrier structure 20 at least partially penetrates through the first electrolyte layer 11, and the diffusion barrier structure 20 communicates with the detection chamber 30, so that the gas to be measured enters the detection chamber 30 through the diffusion barrier structure 20. That is, the diffusion barrier structure 20 needs to communicate with the outside of the oxygen sensor, so that the gas to be measured can diffuse into the detection chamber 30 through the diffusion barrier structure 20. Exemplarily, the diffusion barrier structure 20 can be entirely and penetratingly provided in the first electrolyte layer 11. Exemplarily, a part of the diffusion barrier structure 20 can be penetratingly provided in the first electrolyte layer 11, and the other part is provided outside the first electrolyte layer 11. For example, the other part can be provided in the second electrolyte layer 12, or can extend outside the surface of the first electrolyte layer 11 facing away from the second electrolyte layer 12.
[0049] Reference Figure 3 And Figure 4 , one side of the diffusion barrier structure 20 away from the second electrolyte layer 12 has a first end face 21, that is, the first end face 21 is the end face of the diffusion barrier structure 20 on the side away from the second electrolyte layer 12. The first end face 21 is flush with or protrudes from the surface of the first electrolyte layer 11 facing away from the second electrolyte layer 12. Reference Figure 3 And Figure 4 , the upper end face of the diffusion barrier structure 20 is the first end face 21, and the first end face 21 is flush with the surface of the first electrolyte layer 11 facing away from the second electrolyte layer 12. Of course, in other embodiments, the first end face 21 of the diffusion barrier structure 20 can also protrude from the surface of the first electrolyte layer 11 facing away from the second electrolyte layer 12, that is Figure 3 And Figure 4 In, the first end face 21 is higher than the surface of the first electrolyte layer 11 facing away from the second electrolyte layer 12.
[0050] Compared with the related art, the present application does not need to provide a channel for the gas to be measured, avoiding the deformation of the channel for the gas to be measured caused by the pressure during the forming process such as lamination or hydrostatic pressure, and also avoiding the problem that the diffusion barrier structure 20 is broken due to the shear force from the channel for the gas to be measured or uneven extrusion. In addition, since there are the first electrolyte layer 11 and the second electrolyte layer 12 as supports around the diffusion barrier structure 20, the diffusion barrier structure 20 can be prevented from directly bearing the pressure during the forming process such as lamination or hydrostatic pressure, so that the overall shape of the diffusion barrier structure 20 is protected to the greatest extent. Therefore, the solution shown in the embodiments of the present application avoids the problems of forming the channel for the gas to be measured and maintaining the shape of the channel during the manufacturing process, and also avoids the problems of uneven extrusion deformation and cracking and pressure deformation of the diffusion barrier structure 20. Moreover, the technical solution shown in the present application has a simple structure, reduces the manufacturing difficulty, and the overall shape and internal pore morphology of the diffusion barrier structure 20 are easily controlled, thereby improving the manufacturing yield and detection accuracy of the oxygen sensor.
[0051] Exemplarily, referring to Figure 3 and Figure 4 , the diffusion barrier structure 20 also extends into the detection cavity 30, that is, a part of the diffusion barrier structure 20 also extends downward into the detection cavity 30 located in the second electrolyte layer 12, so as to facilitate introducing the gas to be measured into the detection cavity 30. With this setting method, the detection cavity 30 can be set at any position in the second electrolyte layer 12, and only the diffusion barrier structure 20 needs to be additionally provided in the second electrolyte layer 12 so that the diffusion barrier structure 20 extends from the first electrolyte layer 11 to the detection cavity 30. Of course, in other embodiments, the diffusion barrier structure 20 may not extend into the detection cavity 30. Exemplarily, the diffusion barrier structure 20 may be only located in the first electrolyte layer 11, and the detection cavity 30 is set at a position exactly opposite to the diffusion barrier structure 20, so that it is not necessary to extend the diffusion barrier structure 20 into the detection cavity 30.
[0052] Exemplarily, referring to Figure 3 and Figure 4 , the detection cavity 30 has a first cavity wall 31 and a second cavity wall 32 with opposite positions, wherein the first cavity wall 31 is the surface of the first electrolyte layer 11 facing the second electrolyte layer 12. The diffusion barrier structure 20 also has a second end face 22, and the second end face 22 may be the end face of the diffusion barrier structure 20 opposite to the first end face 21 in position. The second end face 22 abuts against the second cavity wall 32 of the detection cavity 30. Exemplarily, as in Figure 3 and Figure 4 , the upper cavity wall of the detection cavity 30 is the first cavity wall 31, Figure 3 and Figure 4 , the lower cavity wall of the detection cavity 30 is the second cavity wall 32, as in Figure 3 and Figure 4The upper end surface of the diffusion barrier structure 20 is the first end surface 21. Figure 3 and Figure 4 The lower end surface of the diffusion barrier structure 20 is the second end surface 22. The diffusion barrier structure 20 extends all the way to the lower wall of the detection chamber 30 and abuts against the lower wall of the detection chamber 30. This not only facilitates the installation of the diffusion barrier structure 20 but also increases the contact area between the diffusion barrier structure 20 and the detection chamber 30, facilitating the entry of the gas to be measured from the diffusion barrier structure 20 into the detection chamber 30. Of course, in other embodiments, the second end surface 22 of the diffusion barrier structure 20 may not contact the second wall 32 of the detection chamber 30, i.e., a gap may exist between the two.
[0053] For example, the thickness of the first electrolyte layer 11 is D1, the thickness of the second electrolyte layer 12 is D2, and the distance between the first end face 21 and the second end face 22 in the stacking direction is D0, then D0=D1+D2. Wherein, the stacking direction is the stacking direction of the first electrolyte layer 11 and the second electrolyte layer 12, and the stacking direction is parallel to the thickness direction of the first electrolyte layer 11 and the second electrolyte layer 12. For example, Figure 3 and Figure 4 The vertical direction in is the stacking direction of the first electrolyte layer 11 and the second electrolyte layer 12, and is also the thickness direction of the first electrolyte layer 11 and the second electrolyte layer 12. That is, the stacking direction is perpendicular to the surfaces of the first electrolyte layer 11 and the second electrolyte layer 12. Figure 3 and Figure 4 In the embodiment, the vertical distance between the first end face 21 and the second end face 22 of the diffusion barrier structure 20 (also referred to as the height of the diffusion barrier structure 20 ) is equal to the total thickness of the first electrolyte layer 11 and the second electrolyte layer 12 .
[0054] For example, the thickness of the diffusion barrier structure 20 is D0, the thickness of the first electrolyte layer 11 is D1, and the thickness of the second electrolyte layer 12 is D2, then D0=D1+D2 is satisfied. Figure 3 and Figure 4, that is, the diffusion barrier structure 20 longitudinally penetrates from the upper surface of the third electrolyte layer 13 to the upper surface 101 of the oxygen sensor. The thickness herein refers to the direction perpendicular to the upper surface 101 or the lower surface 102 of the oxygen sensor, that is, the diffusion barrier structure 20 is a "longitudinally penetrating type". In this structural design, there is no need to set a gas to be measured channel, which avoids the deformation of the gas to be measured channel caused by the pressure during the forming processes such as lamination or static pressure, and also avoids the problem that the diffusion barrier structure 20 is broken due to the shear force from the gas to be measured channel or uneven extrusion. In addition, since the first electrolyte layer 11 and the second electrolyte layer 12 are used as supports around the diffusion barrier structure 20, the diffusion barrier structure 20 can be prevented from directly bearing the pressure during the forming processes such as lamination or static pressure, so that the overall shape of the diffusion barrier structure 20 is protected to the greatest extent. Therefore, the solution shown in the embodiment of the present application avoids the problems of the formation and shape retention of the gas to be measured channel during the manufacturing process, and also avoids the problems of uneven extrusion deformation cracking and pressure deformation of the diffusion barrier structure 20. Moreover, the technical solution shown in the present application has a simple structure, reduces the manufacturing difficulty, and the overall shape and internal pore morphology of the diffusion barrier structure 20 are easily controlled, thereby improving the manufacturing yield and detection accuracy of the oxygen sensor.
[0055] Regarding the shape of the diffusion barrier structure 20, it can be any structure that can at least partially penetrate through the upper surface and the lower surface of the first electrolyte layer 11. Exemplarily, referring to Figure 3 and Figure 4 , the diffusion barrier structure 20 can be a diffusion barrier column, that is, the shape of the diffusion barrier structure 20 is columnar, and the diffusion barrier structure 20 is a columnar structure with the same cross-sectional shape and size. Exemplarily, the extending direction of the diffusion barrier column can be parallel to the lamination direction of the first electrolyte layer 11 and the second electrolyte layer 12. That is, in Figure 3 and Figure 4 , the extending direction of the diffusion barrier column is the vertical direction, perpendicular to the surfaces of the first electrolyte layer 11 and the second electrolyte layer 12. Of course, in other embodiments, the extending direction of the diffusion barrier column can also form an angle greater than 0° with the lamination direction of the first electrolyte layer 11 and the second electrolyte layer 12, that is, the extending direction of the diffusion barrier column is not parallel to the lamination direction of the first electrolyte layer 11 and the second electrolyte layer 12. It should be understood that in addition to the above-mentioned diffusion barrier column shown for the diffusion barrier structure 20, other shaped diffusion barrier structures 20 can also be used. For example, a frustum-shaped diffusion barrier structure 20 can also be used.
[0056] During the preparation process, referring to Figure 3 and Figure 4, vias can also be formed in the first electrolyte layer 11, and then at least part of the diffusion barrier structure 20 can be formed in the vias by processes such as but not limited to filling and screen printing, simplifying the setting of the diffusion barrier structure 20. Of course, during the preparation process, vias can also be opened in the first electrolyte layer 11, and after the detection cavity 30 is formed in the second electrolyte layer 12, the first electrolyte layer 11 and the second electrolyte layer 12 are stacked. After the first electrolyte layer 11 and the second electrolyte layer 12 are stacked together, a diffusion barrier structure 20 in the form of a columnar structure is formed by screen printing.
[0057] Exemplarily, the diffusion barrier structure 20 can be any one of porous zirconia or porous alumina. Exemplarily, the porosity of the diffusion barrier structure 20 can be 20% - 50%. Exemplarily, by controlling the porosity of the diffusion barrier structure 20, the pressure difference between the detection cavity 30 and the gas to be measured outside the detection cavity 30 can be adjusted, thereby controlling the magnitude of the pump current. Specifically, since the diffusion mode of the gas to be measured in the diffusion barrier structure 20 is physical diffusion, after the porosity of the diffusion barrier structure 20 is determined, the limiting rate of the gas to be measured diffusing into the detection cavity 30 is determined. Refer to Figures 3 to 4 , the pump cell of the oxygen sensor includes a test electrode 53 and a common electrode, and the common electrode therein can be the first common electrode 51. When a voltage is applied across the two ends of the pump cell (the test electrode 53 and the first common electrode 51), a current will be formed inside the pump cell due to the flow of oxygen ions, pumping oxygen out of or into the detection cavity 30. Since there is a limit value for the gas diffusion rate in the diffusion barrier structure 20, the flow rate of oxygen ions in the pump cell will not increase infinitely with the increase of the applied voltage, thus forming a limiting oxygen ion flow, that is, the pump current. Therefore, the magnitude of the pump current can be adjusted by adjusting the porosity of the diffusion barrier structure 20.
[0058] Exemplarily, refer to Figure 3 and Figure 4 , a test electrode 53 is provided on the surface of the first electrolyte layer 11 facing away from the second electrolyte layer 12, and a common electrode is provided in the detection cavity 30. The pump cell of the oxygen sensor includes a test electrode 53 and a common electrode. Exemplarily, an electrode protection layer 61 can be covered on the surface of the test electrode 53 to protect the test electrode 53. Exemplarily, the electrode protection layer 61 is used to cover the part of the test electrode 53 except the part in contact with the rear connector. The connector is used to connect the oxygen sensor to the control circuit part of the oxygen sensor, and the connector part is not shown here. The material of the electrode protection layer 61 can be at least one of zirconia or alumina. Exemplarily, the electrode protection layer 61 can be porous zirconia or porous alumina. Exemplarily, the porosity of the electrode protection layer 61 can be 15% - 45%.
[0059] Exemplarily, refer toFigure 3 and Figure 4 The oxygen sensor further includes a reference chamber 40 for accommodating a reference gas. A reference electrode 54 is disposed in the reference chamber 40. The Nernst cell of the oxygen sensor includes the reference electrode 54 and a common electrode. The above-mentioned pump cell and Nernst cell constitute the functional unit of the oxygen sensor. The Nernst cell is configured to detect the oxygen partial pressure difference between the gas to be measured entering the detection chamber 30 and the reference gas in the reference chamber 40, and feedback and output it in the form of an electrical signal. The pump cell is configured to adjust the oxygen partial pressure in the detection chamber 30 so that the electrical signal output by the Nernst cell remains at about 450 mV.
[0060] Exemplarily, referring to Figure 3 and Figure 4 the common electrode in the detection chamber 30 may include a first common electrode 51 and a second common electrode 52. The first common electrode 51 is located above the detection chamber 30, and the second common electrode 52 is located below the detection chamber 30. Exemplarily, the first common electrode 51 may be disposed on the lower surface of the first electrolyte layer 11, and the second common electrode 52 may be disposed on the upper surface of another electrolyte layer and is opposite to the position of the first common electrode 51. Exemplarily, the pump cell of the oxygen sensor may include the first common electrode 51 and a test electrode 53. Exemplarily, the Nernst cell of the oxygen sensor may include the reference electrode 54 and the second common electrode 52. Of course, in other embodiments, only the above-mentioned first common electrode 51 or second common electrode 52 may be provided.
[0061] There are various ways to set the reference chamber 40. The following are several exemplary ways of setting.
[0062] Exemplarily, the reference chamber 40 may be disposed at a position in a different electrolyte layer from the detection chamber 30. Exemplarily, the reference chamber 40 may be disposed below the detection chamber 30. For example, referring to Figure 3 and Figure 4 the oxygen sensor may further include: a third electrolyte layer 13 and a fourth electrolyte layer 14. The third electrolyte layer 13 is stacked on the surface of the second electrolyte layer 12 facing away from the first electrolyte layer 11; the fourth electrolyte layer 14 is stacked on the surface of the third electrolyte layer 13 facing away from the second electrolyte layer 12. The reference chamber 40 may be disposed in the fourth electrolyte layer 14. Exemplarily, the reference chamber 40 may have a third chamber wall 41 and a fourth chamber wall 42 that are opposite to each other. The third chamber wall 41 is located on the surface of the third electrolyte layer 13 facing the fourth electrolyte layer 14, and the reference electrode 54 may be disposed on the third chamber wall 41, that is, the reference electrode 54 is disposed on the surface of the third electrolyte layer 13 facing the third electrolyte layer 13.
[0063] Of course, in other embodiments, the reference cavity 40 may be disposed in the second electrolyte layer 12, and the reference cavity 40 and the detection cavity 30 are separated by the second electrolyte layer 12. That is, the detection cavity 30 and the reference cavity 40 are located in the same electrolyte layer. Exemplarily, two cavities are provided in the second electrolyte layer 12, and the two cavities are separated by the second electrolyte layer 12. One of the cavities is used as the detection cavity 30 for admitting the gas to be measured. The other cavity serves as the reference cavity 40 for accommodating the reference gas. Of course, in other embodiments, the reference cavity 40 may also be a notch at the edge of the second electrolyte layer 12, that is, the opening of the reference cavity 40 is exactly the notch opening at the edge of the second electrolyte layer 12, so as to facilitate the entry of the reference gas into the reference cavity 40. Exemplarily, the reference electrode 54 is disposed on the upper cavity wall (the third cavity wall 41) of the reference cavity 40. Of course, the reference electrode 54 may also be disposed on the lower cavity wall (the fourth cavity wall 42) of the reference cavity 40.
[0064] Exemplarily, reference Figure 3 and Figure 4 , the oxygen sensor may further include: a heating layer for heating, and the heating layer is used to heat the structures in the reference cavity 40, the detection cavity 30, etc., such as but not limited to, so that they quickly enter the operating temperature. Exemplarily, reference Figure 3 and Figure 4 , the heating layer may be laminated on the surface of the fourth electrolyte layer 14 facing away from the third electrolyte layer 13. In some embodiments, the total thickness of the heating layer and the fourth electrolyte layer 14 may be made equal to the total thickness of the first electrolyte layer 11, the second electrolyte layer 12, and the third electrolyte layer 13. That is, the total thickness longitudinally penetrating from the third electrolyte layer 13 to the upper surface 101 of the oxygen sensor is equal to the total thickness longitudinally penetrating from the fourth electrolyte layer 14 to the lower surface 102 of the oxygen sensor. The thickness herein refers to: the distance between the two opposite surfaces of the electrolyte layer in the direction perpendicular to the upper surface 101 or the lower surface 102 of the oxygen sensor. With this setting method, the oxygen sensor has better symmetry in the structural layout, so that the two symmetrically distributed parts expand or contract asynchronously as much as possible during the heating or cooling process, reducing the risk of bending, cracking, or delamination of the oxygen sensor during the sintering process. In addition, the length of the path through which the heat generated by the heating layer is transmitted upward is also more reasonable, which also improves the detection accuracy of the oxygen sensor.
[0065] When setting the heating layer, various methods can be adopted. Exemplarily, reference Figure 3 and Figure 4 , the heating layer may include: a heating electrode 55, an insulating layer 62, a fifth electrolyte layer 15, and a sixth electrolyte layer 16. Exemplarily, reference Figure 3 and Figure 4, the fifth electrolyte layer 15 may be stacked on the surface of the fourth electrolyte layer 14 facing away from the third electrolyte layer 13. Exemplarily, referring to Figure 3 and Figure 4 , the sixth electrolyte layer 16 may be stacked on the surface of the fifth electrolyte layer 15 facing away from the fourth electrolyte layer 14. Among them, the heating electrode 55 is disposed in the insulating layer 62, that is, the heating electrode 55 is surrounded by the insulating layer 62. A cavity is provided in the fifth electrolyte layer 15 and the second electrolyte, and the insulating layer 62 is disposed in the cavity. The heating electrode 55 is separated from the fifth electrolyte layer 15 and the sixth electrolyte layer 16 by the insulating layer 62. The material of the insulating layer 62 may be, for example, but not limited to, alumina ceramics. Exemplarily, the material of the insulating layer 62 may be dense alumina. Exemplarily, the porosity of the dense alumina as the material of the insulating layer 62 may be less than 5%. Exemplarily, the porosity of the alumina ceramics of the insulating layer 62 may be less than 1%.
[0066] Exemplarily, the material of any one of the test electrode 53, the common electrode, the reference electrode 54, and the heating electrode 55 may be a platinum metal electrode. For example, the material of any one of the test electrode 53, the common electrode, the reference electrode 54, and the heating electrode 55 may be a platinum cermet electrode. Exemplarily, the mass fraction of platinum in the platinum cermet electrode may be 40% to 60%.
[0067] Exemplarily, the material of any one of the above electrolyte layers may be zirconia ceramics, that is, the material of any one of the first electrolyte layer 11 to the sixth electrolyte layer 16 may be zirconia ceramics. Exemplarily, the material of any one of the above electrolyte layers may be zirconia ceramics doped with yttrium oxide or scandium oxide, that is, the material of any one of the first electrolyte layer 11 to the sixth electrolyte layer 16 may be zirconia ceramics. Exemplarily, the molar mass of yttrium oxide or scandium oxide in the zirconia ceramics is 3% to 10%. At this doping concentration, zirconia may have good electrical properties, making the detection accuracy of the oxygen sensor more excellent. Exemplarily, any one of the above electrolyte layers may be a dense electrolyte layer formed by sintering. Thus, in the case where the electrolyte layer is not perforated, gas cannot diffuse, and the gas is made to diffuse as much as possible through diffusion channels such as, for example, but not limited to, the diffusion barrier structure 20, improving the detection accuracy of the oxygen sensor.
[0068] In the various embodiments shown above, by making the first end face 21 of the diffusion barrier structure 20 flush with or protruding from the surface of the first electrolyte layer 11 facing away from the second electrolyte layer 12, the gas to be measured enters the detection chamber 30 through the diffusion barrier structure 20. Compared with the related art, the present application does not need to provide a gas channel to be measured, avoiding the situation where the gas channel to be measured is squeezed and deformed, and also avoiding the situation where the diffusion barrier structure 20 is squeezed and damaged by the deformed gas channel, thereby improving the detection accuracy.
[0069] Compared with the related art, in the structural design shown in some of the above embodiments, there is no need to provide a channel for the gas to be measured, and there is no need to plug the holes of the channel for the gas to be measured during subsequent forming processes such as lamination or static pressure to maintain the shape, avoiding the deformation of the channel for the gas to be measured caused by the pressure during forming processes such as lamination or static pressure, and also avoiding the problem that the diffusion barrier structure 20 is sheared by the channel for the gas to be measured or ruptured due to uneven extrusion. In addition, since there are the first electrolyte layer 11 and the second electrolyte layer 12 as supports around the diffusion barrier structure 20, the diffusion barrier structure 20 can be prevented from directly bearing the pressure during forming processes such as lamination or static pressure, so that the overall shape of the diffusion barrier structure 20 is protected to the greatest extent. Therefore, the solution shown in the embodiments of the present application avoids the problems of forming the channel for the gas to be measured and maintaining the shape of the channel during the manufacturing process, and also avoids the problems of uneven extrusion deformation and cracking and pressure deformation of the diffusion barrier structure 20. Moreover, the technical solution shown in the present application has a simple structure, reduces the manufacturing difficulty, and the overall shape and internal pore morphology of the diffusion barrier structure 20 are easily controlled, thereby improving the manufacturing yield and detection accuracy of the oxygen sensor. It can be seen that although the diffusion barrier structure 20 shown in the present application above is "longitudinally penetrating", the diffusion barrier structure 20 can be prevented from deforming and cracking due to uneven extrusion.
[0070] In addition, the embodiments of the present application also provide a manufacturing method of an oxygen sensor, referring to Figure 3 and Figure 4 , the manufacturing method includes:
[0071] Forming a detection cavity 30 in the second electrolyte layer 12;
[0072] Laminating the first electrolyte layer 11 and the second electrolyte layer 12;
[0073] Forming a diffusion barrier structure 20 at least partially penetrating through the first electrolyte layer 11; the diffusion barrier structure 20 communicates with the detection cavity 30; wherein, one side of the diffusion barrier structure 20 away from the second electrolyte layer 12 has a first end face 21, and the first end face 21 is flush with or protrudes from the surface of the first electrolyte layer 11 facing away from the second electrolyte layer 12.
[0074] In the above solution, by making the first end face 21 of the diffusion barrier structure 20 flush with or protrude from the surface of the first electrolyte layer 11 facing away from the second electrolyte layer 12, the gas to be measured enters the detection cavity 30 through the diffusion barrier structure 20. Compared with the related art, the present application does not need to provide a channel for the gas to be measured, avoiding the situation that the channel for the gas to be measured is extruded and deformed, and also avoiding the situation that the diffusion barrier structure 20 is extruded and damaged by the deformed gas channel, thereby improving the detection accuracy. The following will introduce each of the above steps in detail with reference to the drawings.
[0075] It should be noted that the steps of forming the detection cavity 30 in the second electrolyte layer 12 and laminating the first electrolyte layer 11 and the second electrolyte layer 12 are not in a sequential order. The steps of forming the diffusion barrier structure 20 at least partially penetrating the first electrolyte layer 11 and the step of laminating the first electrolyte layer 11 and the second electrolyte layer 12 are also not in a sequential order.
[0076] Exemplarily, referring to Figure 3 and Figure 4 , the manufacturing method may further include: forming a through hole in the first electrolyte layer 11, and after laminating the first electrolyte layer 11 and the second electrolyte layer 12, the through hole communicates with the detection cavity 30. That is, by adjusting the position of the through hole formed in the first electrolyte layer 11, it is ensured that after the first electrolyte layer 11 and the second electrolyte layer 12 are laminated together, the through hole communicates with the detection cavity 30. At this time, when forming the diffusion barrier structure 20 at least partially penetrating the first electrolyte layer 11, it may include forming the diffusion barrier structure 20 at least filling the through hole. Of course, in addition to filling the through hole completely, the diffusion barrier structure 20 may also extend into the detection cavity 30. The specific extension degree may refer to the description of the oxygen sensor part above and will not be elaborated here.
[0077] During the preparation process, a through hole may also be formed in the first electrolyte layer 11, and then at least part of the structure of the diffusion barrier structure 20 is formed in the through hole by processes such as but not limited to filling and screen printing, simplifying the setting of the diffusion barrier structure 20. Of course, during the preparation process, a through hole may also be opened in the first electrolyte layer 11, and after forming the detection cavity 30 in the second electrolyte layer 12, the first electrolyte layer 11 and the second electrolyte layer 12 are laminated. After the first electrolyte layer 11 and the second electrolyte layer 12 are laminated together, a columnar diffusion barrier structure 20 is formed by screen printing.
[0078] There are various ways to form the through hole in the first electrolyte layer 11. Exemplarily, the through hole in the first electrolyte layer 11 may be formed by laser drilling, mechanical drilling, etc.
[0079] There are various ways to form the detection cavity 30 in the second electrolyte layer 12. Exemplarily, the detection cavity 30 in the second electrolyte layer 12 may be formed by laser drilling, mechanical drilling, etc.
[0080] Exemplarily, after sequentially laminating the first electrolyte layer 11 and the second electrolyte layer 12 and preparing the diffusion barrier structure, and then forming structures such as but not limited to the reference cavity 40, the heating layer, etc., the laminated structure may be sintered together to form an oxygen sensor.
[0081] Furthermore, an embodiment of the present application also provides an engine. Refer to Figure 3 and Figure 4 , the engine includes any one of the above oxygen sensors. Exemplarily, the engine may include an exhaust pipe, and the oxygen sensor may be disposed in the exhaust pipe of the engine for detecting the oxygen concentration in the engine exhaust.
[0082] In addition, an embodiment of the present application also provides a vehicle. Refer to Figure 3 and Figure 4 , the vehicle includes any one of the above oxygen sensors, or any one of the above engines. Exemplarily, the oxygen sensor may be disposed in the cockpit of the vehicle for detecting the oxygen concentration in the cockpit. Exemplarily, when the vehicle includes any one of the above engines, the vehicle may be, for example but not limited to, a fuel vehicle, a hybrid vehicle, etc.
[0083] The present invention has been described through the above embodiments. However, it should be understood that the above embodiments are only for the purpose of illustration and example, and are not intended to limit the present invention to the scope of the described embodiments. In addition, those skilled in the art can understand that the present invention is not limited to the above embodiments, and more variations and modifications can be made according to the teachings of the present invention, and these variations and modifications all fall within the scope of protection required by the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalent scope.
Claims
1. An oxygen sensor, characterized in that, Comprising: A stacked first electrolyte layer and second electrolyte layer, wherein a detection cavity is provided in the second electrolyte layer; A diffusion barrier structure, at least partially penetrating through the first electrolyte layer and communicating with the detection cavity; Wherein, a first end face is provided on a side of the diffusion barrier structure away from the second electrolyte layer, and the first end face is flush with or protrudes from a surface of the first electrolyte layer facing away from the second electrolyte layer.
2. The oxygen sensor according to claim 1, characterized in that, The diffusion barrier structure also extends into the detection cavity.
3. The oxygen sensor according to claim 2, characterized in that The detection cavity has a first cavity wall and a second cavity wall opposite in position, wherein the first cavity wall is located on a surface of the first electrolyte layer facing the second electrolyte layer; A second end face is further provided on the diffusion barrier structure, and the second end face abuts against the second cavity wall of the detection cavity.
4. The oxygen sensor according to claim 1, characterized in that, The diffusion barrier structure is a diffusion barrier column.
5. The oxygen sensor according to claim 4, wherein The extending direction of the diffusion barrier column is parallel to the stacking direction of the first electrolyte layer and the second electrolyte layer.
6. The oxygen sensor according to claim 1, characterized in that, A test electrode is provided on a surface of the first electrolyte layer facing away from the second electrolyte layer, a common electrode is provided in the detection cavity, and a pump cell of the oxygen sensor includes the test electrode and the common electrode.
7. The oxygen sensor according to claim 1, characterized in that, A reference cavity is further included, the reference cavity is used for accommodating a reference gas, a reference electrode is provided in the reference cavity, and a Nernst cell of the oxygen sensor includes the reference electrode and the common electrode.
8. The oxygen sensor according to claim 7, characterized in that, Further comprising: A third electrolyte layer, stacked on a surface of the second electrolyte layer facing away from the first electrolyte layer; A fourth electrolyte layer, stacked on a surface of the third electrolyte layer facing away from the second electrolyte layer; the reference cavity is provided in the fourth electrolyte layer; Wherein, the reference cavity has a third cavity wall and a fourth cavity wall opposite in position, the third cavity wall is located on a surface of the third electrolyte layer facing the fourth electrolyte layer, and the reference electrode is provided on the third cavity wall.
9. The oxygen sensor according to claim 8, characterized in that, Further comprising: A heating layer for heating, the heating layer is stacked on a surface of the fourth electrolyte layer facing away from the third electrolyte layer; Wherein, the total thickness of the heating layer and the fourth electrolyte layer is equal to the total thickness of the first electrolyte layer, the second electrolyte layer and the third electrolyte layer.
10. A manufacturing method of an oxygen sensor, characterized in that, Comprising: Forming a detection cavity in the second electrolyte layer; Stacking the first electrolyte layer and the second electrolyte layer; Forming a diffusion barrier structure at least partially penetrating through the first electrolyte layer; The diffusion barrier structure communicates with the detection cavity; wherein, a first end face is provided on a side of the diffusion barrier structure away from the second electrolyte layer, and the first end face is flush with or protrudes from a surface of the first electrolyte layer facing away from the second electrolyte layer.
11. The manufacturing method according to claim 10, characterized in that, Further comprising: Forming a through hole in the first electrolyte layer, and after stacking the first electrolyte layer and the second electrolyte layer, the through hole communicates with the detection cavity; The forming a diffusion barrier structure at least partially penetrating through the first electrolyte layer includes: forming a diffusion barrier structure at least filled in the through hole.
12. An engine, characterized in that, Comprising: The oxygen sensor according to any one of claims 1 to 11.
13. A vehicle, characterized in that, Comprising: The oxygen sensor according to any one of claims 1 to 11, or the engine according to claim 12.