WO2019105174A1

WO2019105174A1 - Highly thermally-integrated heat pipe type solid oxide fuel cell configuration

Info

Publication number: WO2019105174A1
Application number: PCT/CN2018/113432
Authority: WO
Inventors: 史翊翔; 曾洪瑜; 蔡宁生
Original assignee: 清华大学
Priority date: 2017-11-29
Filing date: 2018-11-01
Publication date: 2019-06-06
Also published as: CN107978771B; CN107978771A

Abstract

A fuel cell, comprising: a core (10), the core (10) being a solid oxide fuel cell core (3), and the solid oxide fuel cell core (3) comprising a cathode layer, an anode layer, and an electrolyte; a metal element (4), the metal element (4) being provided on the outer surface of the core (10); and a thermal conductive element (5), the thermal conductive element (5) being provided on the outer surface of the metal element (4). The cathode layer is connected to the metal element (4).

Description

Highly thermally integrated heat pipe type solid oxide fuel cell configuration

Priority information

The present application claims priority to and the benefit of the patent application Serial No. PCT Application No.

Technical field

The present invention relates to the field of fuel cells, and in particular to fuel cells and their applications, and more particularly to fuel cells and power plants.

Background technique

Solid oxide fuel cell (SOFC) is a clean and efficient power generation unit that converts the chemical energy of fuel directly into electrical energy at high temperatures (600-1000 ° C) in small power plants, portable mobile power supplies, and distributed heat and power. The system has great application prospects.

However, a more efficient solid oxide fuel cell needs further improvement.

Summary of the invention

This application is based on the discovery and recognition of the following facts and issues by the inventors:

During the operation of solid oxide fuel cell (SOFC), due to local reaction or other factors, temperature gradient or local high temperature is easy to occur. The existence of long-term temperature gradient can easily bring thermal stress to the fuel cell. Local high temperature may also cause the phenomenon of local area electrode porous structure sintering and current collector melting. At present, the practical application is to use excessive air to the cathode to prevent the above problems, but the passage of excess air means that a larger fan is needed, which leads to greater energy consumption. For scholars, most of them It is from the perspective of improving the material of the fuel cell to solve this problem. Based on the findings of the above problems, the inventors conducted a lot of research, and improved the structure of the fuel cell from the perspective of thermal energy engineering, and developed a solid oxide fuel cell with a novel structure. The inventor was pleasantly surprised to find that the fuel cell can reduce the internal thermal stress and failure probability of the SOFC, thereby avoiding the occurrence of local high temperature of the battery as much as possible, reducing the temperature gradient in time, achieving good temperature uniformity, and prolonging the service life of the fuel cell.

The present invention aims to solve at least one of the technical problems in the related art to some extent.

In a first aspect of the invention, the invention proposes a fuel cell. According to an embodiment of the present invention, the fuel cell includes: a core, which is a solid oxide fuel cell core, the solid oxide fuel cell core includes an anode layer, a cathode layer, and an electrolyte; a metal member, A metal element is disposed on an outer surface of the core; a thermally conductive element disposed on an outer surface of the metal element; wherein the anode layer is in contact with the metal element. According to the fuel cell of the embodiment of the invention, the local high temperature of the battery can be avoided as much as possible, the temperature gradient can be lowered in time, the temperature uniformity can be achieved, and the service life of the battery can be prolonged.

According to an embodiment of the present invention, the above fuel cell may further include at least one of the following additional technical features:

According to an embodiment of the invention, the metal element is a metal foam. The inventors have found that the metal foam integrates the solid oxide fuel cell core and the heat-conducting element into one unit, which is convenient for forming a large-scale group, has a simple structure, does not require high-temperature sealing, is convenient for testing and assembly, and at the same time, the foam metal The aspect also functions as an anode current collecting. On the other hand, the foam metal has a high porosity, and the gap provides an anode flow path for the fuel cell. Further, the battery can avoid local high temperature of the battery as much as possible, and reduce the time in time. Temperature gradient for good temperature uniformity and extended battery life.

According to an embodiment of the invention, the metal foam comprises at least one selected from the group consisting of foamed nickel, copper foam, and foamed alloy. The inventors have found that the anode metal has a better anode current collecting effect, and the foam metal has a higher porosity, and the gap provides a wider anode flow path for the fuel cell. Further, the fuel cell can further avoid the battery portion. The appearance of high temperature, timely lowering the temperature gradient, the battery temperature is more uniform, and the battery life is longer.

According to an embodiment of the invention, the heat conducting element is tubular, the heat conducting element comprises: a housing, the housing defines a receiving space of a heat conductive medium; a heat conducting medium, the heat conducting medium is disposed in the receiving space; a wick, the attraction core being disposed on an inner sidewall of the housing. The inventors have found that the heat conducting element can quickly transfer a large amount of excess heat in the high temperature region of the battery to the low temperature region, and further, the battery can avoid the local high temperature of the battery as much as possible, reduce the temperature gradient in time, and achieve good temperature uniformity. Extend battery life.

According to an embodiment of the invention, the heat transfer medium is a liquid metal. The inventors have found that the liquid metal has a high heat transfer performance, and by using the latent heat of vaporization of the liquid metal, a large amount of excess heat in the high temperature region of the battery can be quickly conducted to the low temperature region, and further, the battery can further avoid local high temperature of the battery. The appearance of the temperature gradient in time, the battery temperature is more uniform, and the battery life is longer.

According to an embodiment of the invention, the liquid metal comprises at least one selected from the group consisting of liquid sodium, liquid potassium, and liquid alloy. It should be noted that the selection of the liquid metal according to the embodiment of the present invention is not limited as long as it can produce a phase change in the operating temperature range of the solid oxide fuel cell core, has a high thermal conductivity, a high latent heat of vaporization, a high density, Low viscosity and high surface tension, and then utilizing the latent heat of vaporization of the liquid metal, can quickly transfer a large amount of excess heat in the high temperature region of the battery to the low temperature region, so that the battery avoids the local high temperature of the battery as much as possible, and timely reduces the temperature gradient. Good temperature uniformity is within the range of choice.

According to an embodiment of the invention, the solid oxide fuel cell core comprises: an anode layer, the anode layer comprising an anode; a cathode layer comprising a cathode, a cathode mesh and a cathode inlet pipe, the cathode mesh being disposed at An outer surface of the cathode, the cathode inlet tube is disposed on an outer surface of the cathode mesh; and an electrolyte disposed between the anode layer and the cathode layer. The inventors have found that the cathode mesh can function as a cathode current collector, and the solid oxide fuel cell core can be connected to the cathode gas inlet pipe, and the cathode gas inlet pipe can simultaneously preheat the cathode air and The function of the cathode current collection makes full use of the heat source, and the battery reaction effect of the cathode can be made good.

According to an embodiment of the invention, the cathode network comprises at least one selected from the group consisting of a cathode silver mesh and a cathode platinum mesh. The inventors have found that the cathode network has a better current collecting effect, and thus the battery reaction effect of the cathode can be better.

According to an embodiment of the invention, the cathode inlet tube is a tubular element of stainless steel. The inventors have found that the cathode intake pipe can preheat the cathode air while passing through the stainless steel tubular member while supporting the cathode, and then flow through the cathode in the forward direction, so that the cathode battery has a good reaction effect.

According to an embodiment of the invention, the solid oxide fuel cell core is in the form of a flat plate, a through tube or a blind tube. It should be noted that the shape or the classification of the solid oxide fuel cell core according to the embodiment of the present invention is not limited as long as the battery composed of the metal component and the heat conduction component can avoid the occurrence of local high temperature of the battery, and timely reduce the temperature gradient. To achieve good temperature uniformity is within the range of choice. Among them, when the solid oxide fuel cell core is a blind tube, it does not need to be sealed, which is convenient for testing and assembly.

In a second aspect of the invention, the invention proposes a power plant. According to an embodiment of the present invention, the power generating apparatus includes: a device housing; and the fuel cell according to any one of the above aspects, wherein the battery is disposed in the device housing. The fuel cell of the power generating apparatus according to the embodiment of the present invention can avoid the occurrence of local high temperature of the battery, reduce the temperature gradient in time, achieve good temperature uniformity, and prolong the service life of the battery.

DRAWINGS

1 is a schematic structural view of a fuel cell according to an embodiment of the present invention;

2 is a schematic structural view of a heat conductive element according to an embodiment of the present invention;

3 is a schematic view showing the structure of a solid oxide fuel cell core according to an embodiment of the present invention.

Reference mark:

1—cathode intake pipe

2—Cathode mesh

3—Solid oxide fuel cell core

4—foam metal

5—thermally conductive components

6—cathode wire

7—Anode wire

8—Liquid metal vapor

9—spirer

10—housing

11—cathode

12-electrolyte

13-anode

Detailed ways

Embodiments of the invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the drawings are intended to be illustrative of the invention and are not to be construed as limiting.

The fuel cell

In a first aspect of the invention, the invention proposes a fuel cell. According to an embodiment of the invention, the fuel cell comprises: a core, the core being a solid oxide fuel cell core, the solid oxide fuel cell core comprising an anode layer, a cathode layer and an electrolyte; a metal element, the metal An element is disposed on an outer surface of the core; a thermally conductive element disposed on an outer surface of the metal element; wherein the anode layer is in contact with the metal element. According to the fuel cell of the embodiment of the invention, local high temperature of the fuel cell can be avoided as much as possible, the temperature gradient can be lowered in time, good temperature uniformity can be achieved, and the service life of the fuel cell can be prolonged.

According to an embodiment of the invention, referring to Figure 1, the metal component is a metal foam. The inventors have found that the metal foam 3 integrates the solid oxide fuel cell core 3 and the heat-conducting element 5 as a whole, which is convenient for forming a large-scale group, has a simple structure, does not require high-temperature sealing, is convenient for testing and assembly, and at the same time, the foam On the one hand, the metal also functions as an anode current collector, which is connected to the anode lead 7 and connected to the external circuit. On the other hand, the metal foam has a high porosity, and the gap provides an anode flow path for the fuel cell. Further, the battery The local high temperature of the battery can be avoided as much as possible, the temperature gradient can be lowered in time, the temperature uniformity can be achieved, and the service life of the fuel cell can be prolonged. Wherein, the anode fuel undergoes a catalytic reaction through the metal foam, and further diffuses into the interior of the anode 13, and an electrochemical reaction occurs at the three-phase interface.

According to an embodiment of the invention, the metal foam comprises at least one selected from the group consisting of foamed nickel, copper foam, and foamed alloy. The inventors have found that the foam metal has a better anode current collecting effect, and the foam metal has a higher porosity, and the gap provides a wider anode flow path for the fuel cell. Further, the battery can further avoid local high temperature of the battery. Appears to reduce the temperature gradient in time, the battery temperature is more uniform, and the battery life is longer.

According to an embodiment of the present invention, referring to FIG. 2, the heat conducting element is tubular, and the heat conducting element comprises: a housing 10, the inside of the housing 10 is evacuated, and a housing space of the heat conducting medium is defined in the housing 10; a medium, the heat conductive medium is disposed in the accommodating space; a wick 9, the wick 9 is disposed on an inner side wall of the casing. The inventors have found that the rapid heat transfer characteristics of the heat conducting element can quickly transfer a large amount of excess heat in the high temperature region of the battery to the low temperature region. Further, the battery can avoid the local high temperature of the battery as much as possible, reduce the temperature gradient in time, and achieve good performance. Temperature uniformity extends battery life.

According to an embodiment of the invention, referring to Figure 2, the thermally conductive medium is a liquid metal. The inventors have found that the liquid metal has a high heat transfer performance, and by using the latent heat of vaporization of the liquid metal, a large amount of excess heat in the high temperature region of the battery can be quickly conducted to the low temperature region, and further, the battery can further avoid local high temperature of the battery. The appearance of the temperature gradient in time, the battery temperature is more uniform, and the battery life is longer. Among them, according to the phase change of the liquid metal, the high temperature heat pipe can be divided into three parts: the evaporation section, the adiabatic section and the condensation section. After the heat is transferred from the heat source to the liquid-vapor separation interface through the inner wall of the casing 10 of the heat-conducting element and the wick 9, the liquid metal evaporates at the interface, and the evaporated steam is rapidly transmitted to the vapor pressure under the action of the saturated vapor pressure. The condensation section is condensed on the gas-liquid interface of the condensation section, and heat is transferred to the cold source through the inner wall of the liquid absorbing core 9 and the shell 10 of the heat-conducting element to complete a rapid heat transfer process. The liquid metal condensed in the condensation section is returned to the evaporation section under the capillary action of the wick to perform the next heat transfer process.

According to an embodiment of the invention, the liquid metal comprises at least one selected from the group consisting of liquid sodium, liquid potassium, and liquid alloy. It should be noted that the selection of the liquid metal according to the embodiment of the present invention is not limited as long as it can produce a phase change in the operating temperature range of the solid oxide fuel cell core, has a high thermal conductivity, a high latent heat of vaporization, a high density, Low viscosity and high surface tension, and then utilizing the latent heat of vaporization of the liquid metal, can rapidly transfer a large amount of excess heat in the high temperature region of the fuel cell to the low temperature region, so that the fuel cell avoids the local high temperature of the battery as much as possible, and timely reduces the temperature gradient. To achieve good temperature uniformity is within the range of choice.

According to an embodiment of the present invention, referring to FIGS. 1 and 3, the solid oxide fuel cell core includes an anode layer including an anode 13 and a cathode layer including a cathode 11, a cathode mesh 2, and a cathode intake pipe 1, the cathode mesh 2 is disposed on an outer surface of the cathode 11, the cathode intake pipe 1 is disposed on an outer surface of the cathode mesh 2; an electrolyte 12, the electrolyte is disposed on the anode layer and Between the cathode layers. The inventors have found that the cathode mesh 2 can function as a cathode current collector, and the solid oxide fuel cell core can be connected to the cathode gas inlet pipe, and the cathode gas inlet pipe can simultaneously preheat the cathode air. With the action of the cathode current collection, the heat source can be fully utilized, and the cathode reaction effect of the fuel cell can be improved. The cathode of the solid oxide fuel cell core is collected by the cathode network 2 and conducted to the cathode inlet pipe 1, and is connected to the cathode wire 6 by the cathode inlet pipe 1, and the cathode wire 6 is connected to the external circuit. The cathode gas passes through the cathode inlet pipe 1, flows through the cathode mesh 2, and then diffuses to the cathode 11 of the solid oxide fuel cell core, and the cathode inlet pipe 1 simultaneously preheats the cathode inlet air.

According to an embodiment of the invention, the cathode network comprises at least one selected from the group consisting of a cathode silver mesh and a cathode platinum mesh. The inventors have found that the cathode mesh has a better current collecting effect, and thus the battery reaction effect of the cathode can be better.

Power Equipment

In still another aspect of the present invention, the present invention provides a power generating apparatus. According to an embodiment of the present invention, the power generating apparatus includes: a device housing; and the fuel cell according to any one of the above aspects, wherein the battery is disposed in the device housing. The fuel cell of the power generating apparatus according to the embodiment of the present invention can avoid the occurrence of local high temperature of the battery, reduce the temperature gradient in time, achieve good temperature uniformity, and prolong the service life of the battery.

Example

The inventors tested the temperature distribution and electrochemical performance of a highly thermally coupled heat pipe type solid oxide fuel cell under the new configuration. The experimental results show that under the same size scale and experimental conditions, the axial temperature gradient of the new tubular solid oxide fuel cell can be reduced by 1/3, which can reduce the thermal stress inside the fuel cell by an order of magnitude. The local maximum temperature is greatly reduced, and the adverse effects caused by the local high temperature are reduced, thereby prolonging the working life. Electrochemical performance test results show that under stable working conditions, the power of single-tube fuel cell can be increased from 1.08W to 1.78W, fuel cell performance is significantly improved, and power generation efficiency is increased.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " After, "Left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inside", "Outside", "Clockwise", "Counterclockwise", "Axial", The orientation or positional relationship of the "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is merely for convenience of description of the present invention and simplified description, and does not indicate or imply the indicated device or component. It must be constructed and operated in a particular orientation, and is not to be construed as limiting the invention.

Moreover, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" or "second" may include at least one of the features, either explicitly or implicitly. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless specifically defined otherwise.

In the present invention, the terms "installation", "connected", "connected", "fixed" and the like shall be understood broadly, and may be either a fixed connection or a detachable connection, unless explicitly stated and defined otherwise. Or in one piece; it may be a mechanical connection, or it may be an electrical connection or a communication with each other; it may be directly connected or indirectly connected through an intermediate medium, and may be an internal connection of two elements or an interaction relationship between two elements. Unless otherwise expressly defined. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.

In the present invention, the first feature "on" or "under" the second feature may be a direct contact of the first and second features, or the first and second features may be indirectly through an intermediate medium, unless otherwise explicitly stated and defined. contact. Moreover, the first feature "above", "above" and "above" the second feature may be that the first feature is directly above or above the second feature, or merely that the first feature level is higher than the second feature. The first feature "below", "below" and "below" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely that the first feature level is less than the second feature.

In the description of the present specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means a specific feature described in connection with the embodiment or example. A structure, material or feature is included in at least one embodiment or example of the invention. In the present specification, the schematic representation of the above terms is not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, various embodiments or examples described in the specification, as well as features of various embodiments or examples, may be combined and combined.

Although the embodiments of the present invention have been shown and described, it is understood that the above-described embodiments are illustrative and are not to be construed as limiting the scope of the invention. The embodiments are subject to variations, modifications, substitutions and variations.

Claims

A fuel cell, comprising:

a core, the core is a solid oxide fuel cell core, the solid oxide fuel cell core comprising an anode layer, a cathode layer and an electrolyte;

a metal component disposed on an outer surface of the core;

a thermally conductive element disposed on an outer surface of the metal element;

Wherein the anode layer is in contact with the metal component.
A fuel cell according to claim 1 wherein said metal component is a metal foam.
The fuel cell according to claim 2, wherein the metal foam comprises at least one selected from the group consisting of foamed nickel, copper foam, and foamed alloy.
The fuel cell of claim 1 wherein said thermally conductive element is tubular and said thermally conductive element comprises:

a housing defining an accommodation space for the heat conductive medium;

a heat conductive medium, the heat conductive medium being disposed in the receiving space;

a wick, the wick being disposed on an inner sidewall of the housing.
The fuel cell according to claim 4, wherein said heat transfer medium is a liquid metal.
The fuel cell according to claim 5, wherein said liquid metal comprises at least one selected from the group consisting of liquid sodium, liquid potassium, and liquid alloy.
The fuel cell according to claim 1, wherein said solid oxide fuel cell core comprises:

An anode layer, the anode layer comprising an anode;

a cathode layer, the cathode layer comprising a cathode, a cathode mesh and a cathode inlet pipe, the cathode mesh being disposed on an outer surface of the cathode, the cathode inlet pipe being disposed on an outer surface of the cathode mesh;

An electrolyte disposed between the anode layer and the cathode layer.
The fuel cell according to claim 7, wherein said cathode mesh comprises at least one selected from the group consisting of a cathode silver mesh and a cathode platinum mesh.
The fuel cell according to claim 7, wherein said cathode intake pipe is a tubular member of stainless steel;

Optionally, the solid oxide fuel cell core is in the form of a flat plate, a tubular or a blind tube.
A power generation device, comprising:

A device housing; and the fuel cell according to any one of claims 1 to 9, wherein the fuel cell is disposed in the device housing.