An electrochemical energy conversion device and a power generation device including the same

Abstract

The application relates to the field of electrochemistry and discloses an electrochemical energy conversion device and a power generation device comprising the same, the electrochemical energy conversion device comprising a uniform temperature cover, an electric pile group, an insulating component, a second fluid air inlet pipeline and a second fluid air outlet pipeline, wherein the first fluid required in the reaction process of the electrochemical energy conversion device does not need to be input and discharged through a first fluid pipeline, the overall structure of the electrochemical energy conversion device is simplified, and the electric pile is more convenient to overhaul and disassemble; secondly, due to the existence of the uniform temperature cover, the discharged first fluid can fully contact the cover body of the uniform temperature cover and conduct heat to the first cavity through the cover body, so that good uniform temperature effect can be realized on the first fluid in the electrochemical energy conversion device, the first fluid entering the uniform temperature cover and the first fluid discharged from the uniform temperature cover after participating in the reaction have close or same temperatures, the temperature difference between the first cavity and the second cavity is reduced, and the performance attenuation and damage of the electric pile caused by local thermal expansion are inhibited.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electrochemistry, in particular to an electrochemical energy conversion device and a power generation device comprising the same. BACKGROUND

[0002] The mutual conversion between electrical energy and chemical energy is realized by various electrochemical energy conversion devices, such as fuel cells and electrolytic cells. Common fuel cells include alkaline fuel cells (AFC), phosphoric acid fuel cells (PAFC), molten carbonate fuel cells (MCFC), proton exchange membrane fuel cells (PEMFC), direct methanol fuel cells (DMFC), solid oxide fuel cells (SOFC), etc. Common electrolytic cells include alkaline electrolytic cells (AWE), proton exchange membrane water electrolytic cells (PEMWE), anion exchange membrane water electrolytic cells (AEMWE), and solid oxide electrolytic cells (SOEC), etc.

[0003] Among them, solid oxide fuel cells (SOFC) and solid oxide electrolytic cells (SOEC) can be collectively referred to as solid oxide cells (SOC). Solid oxide cells (SOC) are advanced electrochemical energy storage and conversion devices, and have wide application prospects in the fields of clean energy power generation and CO2 conversion. Solid oxide fuel cells (SOFC) are energy conversion devices that can directly convert the chemical energy stored in fuel and oxidant into electrical energy. They have a high operating temperature, usually in the range of 700-1000℃, so they can be used for combined heat and power generation while generating electricity, with an energy utilization efficiency of up to 90%. Solid oxide electrolytic cells (SOEC) are electrochemical energy conversion devices that convert electrical energy and heat energy into chemical energy. Their reaction is the reverse of that of solid oxide fuel cells. As one of the main technical routes for water electrolysis to produce hydrogen today, SOECs usually operate at 700-850℃, with an electrolysis efficiency of up to 85%-95%.

[0004] Existing electrochemical energy conversion devices usually have multiple stacks arranged in a certain distribution. However, the existing electrochemical energy conversion devices usually introduce and discharge gas flow through gas pipes, which has a complex overall pipe structure, is not conducive to maintenance and replacement of the stacks, and there is a certain temperature difference between the introduced and discharged gases, resulting in uneven internal temperature. Local thermal expansion can quickly degrade the performance of the stacks, and even cause damage to the stacks. SUMMARY

[0005] The purpose of the present application is to provide an electrochemical energy conversion device.

[0006] To achieve the above purpose, the first aspect of the present application provides an electrochemical energy conversion device, comprising:

[0007] A uniform temperature cover, an accommodating cavity is formed in the inside of the uniform temperature cover, the uniform temperature cover is made of a heat conductive material, the uniform temperature cover has a first fluid inlet and a first fluid outlet;

[0008] A stack group formed by at least one stack array is arranged in the accommodating cavity, the stack forms a first fluid flow channel;

[0009] An insulation component is arranged between the stack group and the uniform temperature cover;

[0010] The stack group and the insulation component together divide the accommodating cavity into multiple cavities, the multiple cavities include a first cavity and a second cavity, the first cavity is in communication with the first fluid inlet, the second cavity is in communication with the first fluid outlet, and the first cavity and the second cavity are in communication through the first fluid flow channel.

[0011] In some embodiments of the present application, the thermal conductivity of the uniform temperature cover is 1-40 W / m·k.

[0012] In some embodiments of the present application, the uniform temperature cover is made of one or more materials selected from SUS 310S, SUS 310, SUS 444, SUS 430, and SUS 316.

[0013] In some embodiments of the present application, the thermal conductivity of the insulation component is 1-30 W / m·k.

[0014] In some embodiments of the present application, the uniform temperature cover includes multiple wall surfaces surrounding the accommodating cavity, the area of the wall surface where the first fluid inlet is arranged is B, the area of the first fluid inlet is A, and A / B=0.01-0.95.

[0015] In some embodiments of the present application, the distance between the bottom surface of the stack group and the inner bottom surface of the uniform temperature cover is C, the distance between the top surface of the stack group and the inner top surface of the uniform temperature cover is D, the distance between the side surface of the stack group and the corresponding inner side surface of the uniform temperature cover is E, and the thickness of the insulation component is F, then C / F=1-4, D / F=1-4, and E / F=1-2.

[0016] It can be understood that the side surface of the stack group does not correspond to the cavity, the stack has a main surface corresponding to the cavity, and the outlet and the inlet of the first fluid flow channel are located on the main surface.

[0017] In some embodiments of the present application, sealing cotton is further included, and the sealing cotton is arranged between the insulation component and the uniform temperature cover.

[0018] In some embodiments of the present application, the uniform temperature cover is provided with a second fluid inlet hole and a second fluid outlet hole;

[0019] The electrochemical energy conversion device further comprises a second fluid inlet pipe and a second fluid outlet pipe;

[0020] The first cavity is provided with the second fluid inlet pipe, the second fluid inlet pipe is connected with the uniform temperature cover through the second fluid inlet hole, and the second fluid inlet pipe is connected with the electric pile;

[0021] The second cavity is provided with the second fluid outlet pipe, the second fluid outlet pipe is connected with the uniform temperature cover through the second fluid outlet hole, and the second fluid outlet pipe is connected with the electric pile.

[0022] In some embodiments of the present application, the uniform temperature cover comprises an end face, a projection face N1 of the first cavity on the end face, a long side L1 of the projection face N1, a short side W1 of the projection face N1, a projection point O1 of an axis of the second fluid inlet pipe on the end face, and a distance X1 between the point O1 and the long side L1, wherein 0.1W1≤X1≤0.9W1;

[0023] and / or,

[0024] The uniform temperature cover comprises an end face, a projection face N2 of the second cavity on the end face, a long side L2 of the projection face N2, a short side W2 of the projection face N2, a projection point O2 of an axis of the second fluid outlet pipe on the end face, and a distance X2 between the point O2 and the long side L2, wherein 0.1W2≤X2≤0.9W2.

[0025] In some embodiments of the present application, the uniform temperature cover comprises an end face, a projection face N1 of the first cavity on the end face, a short side W1 of the projection face N1, a longest diagonal length Z1 of the projection face N1, a projection point O1 of an axis of the second fluid inlet pipe on the end face, a projection P1 of a center point of the first fluid inlet on the end face, and a distance Y1 between the point P1 and the point O1, wherein 0.1W1≤Y1≤0.85Z1;

[0026] and / or,

[0027] The second cavity has a projection face N2 on the end face, a short side of the projection face N2 is W2, a longest diagonal length of the projection face N2 is Z2, a projection point of an axis of the second fluid outlet pipeline on the end face is O2, a projection of a center point of the first fluid outlet on the end face is P2, a distance between the P2 and the O2 is Y2, and 0.1W2≤Y2≤0.85Z2.

[0028] In some embodiments of the present application, the stack group comprises a plurality of stacks, at least two adjacent stacks are arranged in series, and the positive and negative electrodes of the two stacks arranged in series are reversely arranged, and the insulation component is arranged between the two adjacent stacks.

[0029] It can be understood that the two adjacent stacks in the same row of stack groups do not form the cavity, and the cavity can be formed between the different rows of stack groups.

[0030] In some embodiments of the present application, the second fluid inlet pipeline and the second fluid outlet pipeline are both provided with an insulation section.

[0031] In some embodiments of the present application, the electric lead assembly comprises a conductive part and an electric connection part, the conductive part is arranged between the insulation component and the stack group and is electrically connected with the stack group, and the electric connection part penetrates through the uniform temperature cover and the insulation component and is connected with the conductive part.

[0032] The present application provides an electrochemical energy conversion device, which has the following beneficial effects compared with the prior art:

[0033] The electrochemical energy conversion device provided by the application comprises a uniform temperature cover, an electric pile group containing at least one electric pile, and an insulation part, the uniform temperature cover, the electric pile group and the insulation part are matched with each other to form multiple cavities including a first cavity and a second cavity inside the uniform temperature cover, a first fluid required for reaction of the electrochemical energy conversion device enters the first cavity through a first fluid inlet, then flows into a first fluid flow channel and enters each single cell of the electric pile to react, and the cathode tail gas after reaction flows into the second cavity through the first fluid flow channel and then is discharged through a first fluid outlet, that is, the first fluid required for reaction of the electrochemical energy conversion device does not need to be input and discharged through a first fluid pipeline, the overall structure of the electrochemical energy conversion device is simplified, and the electric pile is more convenient to overhaul and disassemble; secondly, the uniform temperature cover seals the whole electrochemical energy conversion device to form a good sealing environment and prevent the first fluid or the second fluid from leaking, the temperature of the first fluid discharged by the electric pile unit is higher than that of the input first fluid, due to the existence of the uniform temperature cover, the discharged first fluid can fully contact the cover body of the uniform temperature cover and conduct heat to the first cavity through the cover body, so that good uniform temperature effect of the first fluid inside the electrochemical energy conversion device can be achieved, the first fluid entering the uniform temperature cover and the first fluid discharged from the uniform temperature cover after participating in the reaction have close or same temperature, and then the temperature difference between the first cavity and the second cavity is reduced, and the performance decay and damage of the electric pile caused by local thermal expansion are inhibited. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 It is an overall structure schematic diagram of the electrochemical energy conversion device of the embodiment of the application;

[0035] Figure 2 It is a structure schematic diagram of the electrochemical energy conversion device of the embodiment of the application;

[0036] Figure 3 It is a bottom view schematic diagram of the electrochemical energy conversion device of the embodiment of the application;

[0037] Figure 4 It is a top view schematic diagram of the electrochemical energy conversion device of the embodiment of the application;

[0038] Figure 5 It is Figure 4 a sectional view along the X-X direction;

[0039] Figure 6 It is a structure schematic diagram of the electrochemical energy conversion device of the embodiment of the application (part of the uniform temperature cover is omitted);

[0040] Figure 7 It is a front view structure schematic diagram of the electrochemical energy conversion device of the embodiment of the application (part of the uniform temperature cover is omitted);

[0041] Figure 8 As shown in FIG. 1, the first fluid inlet 11 is arranged on the first cavity 13, and the first fluid outlet 12 is arranged on the second cavity 14. Figure 7 As shown in FIG. 2, the second fluid inlet 16 is arranged on the second cavity 14, and the second fluid outlet 17 is arranged on the first cavity 13.

[0042] Figure 9 As shown in FIG. 3, the second fluid inlet 16 is arranged on the second cavity 14, and the second fluid outlet 17 is arranged on the first cavity 13. Figure 7 As shown in FIG. 4, the second fluid inlet 16 is arranged on the second cavity 14, and the second fluid outlet 17 is arranged on the first cavity 13.

[0043] In the figure: 1, the uniform temperature cover; 11, the first fluid inlet; 12, the first fluid outlet; 13, the first cavity; 14, the second cavity; 15, the end face; 16, the second fluid inlet hole; 17, the second fluid outlet hole; 200, the electric pile group; 20, the electric pile; 2, the electric pile unit; 21, the electric pile unit top plate; 22, a plurality of single cells; 23, the electric pile unit bottom plate; 3, the insulating part; 4, the sealing cotton; 5, the second fluid inlet pipeline; 6, the second fluid outlet pipeline; 61, the fluid equal distribution device; 71, the conductive part; 72, the electric connection part. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0045] It should be understood that, in the description of the present application, the orientations or positional relationships indicated by the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. The terms "first" and "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features, i.e. the features with "first" and "second" can explicitly or implicitly include one or more of the features. In addition, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0046] It should be noted that in the description of the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0047] As shown in Figure 1 , Figure 6 and Figure 7 , the embodiment of the present application provides an electrochemical energy conversion device, which comprises a uniform temperature cover 1, an electric pile group 200 and an insulating part 3.

[0048] Referring to Figure 2 and Figure 3 , the uniform temperature cover 1 is internally formed with a containing cavity, the uniform temperature cover 1 is made of a heat-conducting material, the uniform temperature cover 1 has a first fluid inlet port 11 and a first fluid outlet port 12, preferably, the first fluid inlet port 11 and the first fluid outlet port 12 are arranged on the same end surface 15 of the uniform temperature cover 1, of course, the first fluid inlet port 11 and the first fluid outlet port 12 can also be arranged on different end surfaces 15, or arranged on the side surface of the uniform temperature cover 1. Preferably, it is made of one or more stainless steel materials selected from SUS 310S, SUS 310, SUS 444, SUS 430 and SUS 316.

[0049] In order to better realize the uniform temperature effect of the uniform temperature cover 1, in the embodiment, the heat conductivity coefficient of the uniform temperature cover 1 is 1 ~40 W / m·k. In the power generation working condition, if the heat conductivity coefficient of the uniform temperature cover 1 is less than 1 W / m·k, the heat near the first fluid outlet port 12 of the uniform temperature cover 1 cannot be timely transmitted to the first fluid inlet port 11 of the uniform temperature cover 1, so that the temperature difference between the inlet and outlet of the uniform temperature cover 1 and the inlet and outlet of the electric pile unit 2 is increased, resulting in the reduction of the service life of the electric pile unit 2; in the power generation working condition, if the heat conductivity coefficient of the uniform temperature cover 1 is greater than 40 W / m·k, then the heat of the electrochemical energy conversion device will be excessively released to the surrounding environment, at this time, more heat is needed to maintain the operation of the electrochemical energy conversion device, which increases the energy consumption of the whole electrochemical energy conversion device system. At the same time, if the arrangement mode of compact connection of multiple electrochemical energy conversion devices is adopted, the temperature fields of the similar electrochemical energy conversion devices will affect each other, increasing the risk of abnormal operation of the electrochemical energy conversion device.

[0050] Referring to Figure 7The stack group 200 is arranged in the accommodating cavity, and the stack group 200 is arranged by two stacks 20. The stack 20 is formed with a first fluid flow channel (not shown in the figure). Specifically, the stack unit 2 comprises a stack unit bottom plate 23, a plurality of single cells 22, and a stack unit top plate 21. The single cells are arranged between the stack unit bottom plate and the stack unit top plate and connected with the two plates. The plurality of stack units 2 are arranged in a stack by being stacked up and down, and the stack 20 can also be formed by a single stack unit 2. The stack unit bottom plate 23 and the stack unit top plate 21 are beneficial to positioning during assembly of the electrochemical energy conversion device system, and can also protect the overall structure of the stack unit 2. In addition, the stack unit bottom plate 23 or the stack unit top plate 21 can be provided with a gas guide hole to facilitate the second fluid to pass through each single cell and react.

[0051] It should be understood that in the SOFC, the first fluid is air, and the second fluid is fuel gas. In the SOEC, the first fluid is air, and the second fluid is water vapor. The purpose of introducing air in the SOEC is to provide a certain oxygen partial pressure at the beginning of the reaction, and to reduce the oxygen partial pressure in the electrochemical energy conversion device during the reaction, so as to facilitate the smooth progress of the reaction and reduce the temperature of the reaction process in the electrochemical energy conversion device.

[0052] Optionally, referring to Figure 7 In the embodiment, the stack unit bottom plate 23, the stack unit top plate 21, and the uniform temperature cover 1 are made of the same material. The electrochemical energy conversion device usually operates at 800-1000℃, and the metal will expand at this working temperature. If the material of the uniform temperature cover 1 is inconsistent with the materials of the stack unit top plate 21, the stack unit bottom plate 23, and the connecting components, thermal expansion mismatch will occur between the two. Specifically, if the expansion coefficients of the stack unit top plate 21, the stack unit bottom plate 23, and the connecting components are greater than the expansion coefficient of the uniform temperature cover 1, the stack 20 will push against the uniform temperature cover 1, causing deformation of the latter. If the expansion coefficients of the stack unit top plate 21, the stack unit bottom plate 23, and the connecting components are less than the expansion coefficient of the uniform temperature cover 1, the gap between the uniform temperature cover 1 and the stack will gradually increase with the increase of the temperature, and the sealing structure will be damaged, causing more reaction gas to flow directly to the reaction gas outlet instead of flowing through the stack 20. In severe cases, the stack 20 will be damaged due to insufficient reaction gas content.

[0053] Optionally, referring to Figure 6In the embodiment, the stack group 200 is provided with multiple stacks 20, and at least two stacks 20 are provided in series, and the positive and negative electrodes of the two stacks 20 provided in series are reversely arranged, so that the positive and negative electrode leads of the stack 20 can be located on the same side, which simplifies the design of the electrochemical energy conversion device and facilitates subsequent testing and system assembly. Specifically, two or more stacks 20 can be electrically connected in series through a conductive plate or a conductive wire, and the conductive plate is preferably used. Since the operating temperature of the SOC is very high, and the positive and negative electrodes of the battery group are in a high-temperature region, if a conductive wire is used to realize electrical contact between the two stacks 20, the conductive wire is prone to oxidation, fracture and other failure behaviors at high temperatures, and therefore the conductive plate is preferably used to realize electrical contact between the two stacks 20.

[0054] Optionally, referring to Figure 7 In the embodiment, an insulating component 3 is arranged between the two adjacent stacks 20. In the electrochemical energy conversion device, the distance between the adjacent stacks is close, and if the insulating component 3 is not arranged between the stacks, short circuit and other failures caused by electrical breakdown are likely to occur, and at the same time, the insulating component 3 is also a necessary component for forming the first cavity 13 and the second cavity 14 in the uniform temperature cover 1, otherwise the first fluid can directly flow through the two stacks 20, resulting in that no reaction or low reaction efficiency occurs in the stacks.

[0055] It should be understood that the number of cavities in the electrochemical energy conversion device is related to the number of rows of the stack group. For example, when there are two stacks 20 in the electrochemical energy conversion device, the positive and negative electrodes of the two stacks 20 are reversely arranged and electrically connected in series, and there is one first cavity 13 and one second cavity 14 in the electrochemical energy conversion device. The first fluid required for the reaction of the electrochemical energy conversion device enters the first cavity 13 through the first fluid inlet 11 provided on the uniform temperature cover 1, then flows into the first fluid flow channel in the two stacks 20 and enters each single cell in the two stacks 20 for reaction, and the cathode tail gas after the reaction flows into the second cavity 14 through the first fluid flow channel in the two stacks 20, and then is discharged from the electrochemical energy conversion device through the first fluid outlet 12. When there are more than two even-numbered stacks 20 in the electrochemical energy conversion device and arranged in the same row, the stacks 20 can be all electrically connected in series, and only two lines of positive and negative electrodes are led out from the same side. In addition, the more than two even-numbered stacks 20 can also be connected in series or partially connected in series, and then multiple lines are led out from the same side. In the above case, there are still two cavities, i.e., the first cavity 13 and the second cavity 14, in the electrochemical energy conversion device.

[0056] When the stack group in the electrochemical energy conversion device has two rows or more rows, the number of cavities is not less than 3, and an intermediate cavity is formed between the two adjacent stack groups. The intermediate cavity can also be used as the first cavity 13 for gas inlet or the second cavity 14 for gas outlet.

[0057] Optionally, such as Figure 5 As shown, in this embodiment, the electrochemical energy conversion device further includes an electrical connection component, which includes a conductive part 71 and an electrical connection part 72. The conductive part 71 is the aforementioned conductive plate, which is disposed between the insulating component 3 and the fuel cell stack 200 and is electrically connected to the fuel cell stack 200. The electrical connection part 72 passes through the temperature equalization cover 1 and the insulating component 3 and is connected to the conductive part 71. The electrochemical energy conversion device of the present invention includes two or more fuel cells, which not only has a compact structure and high internal space utilization, but also improves the overall power generation efficiency of the electrochemical energy conversion device. Furthermore, every two fuel cells can be electrically connected through the conductive plate, which is beneficial for leading out the electrical energy generated by the electrochemical energy conversion device in the same direction, making the overall layout structure more reasonable.

[0058] See Figure 5 An insulating component 3 is disposed between the fuel cell stack 200 and the temperature equalization cover 1, and is made of one or more insulating materials selected from ceramic, glass, rubber, and mica. The electrochemical energy conversion device generates high voltage and high current during operation. The insulating component 3 between the temperature equalization cover 1 and the fuel cell stack 200 prevents leakage and potential safety accidents. At least one top, bottom, and side of the fuel cell stack 200 are relatively close to the temperature equalization cover 1; therefore, covering the top, bottom, and / or sides of the fuel cell stack 200 with the insulating component 3 can prevent leakage and other safety accidents.

[0059] To achieve better temperature uniformity, optionally in this embodiment, the thermal conductivity of the insulating component 3 is 1~30 W / m·K. If the thermal conductivity of the insulating component 3 is less than 1 W / m·K, the temperature of the side, bottom and / or top surfaces of the fuel cell stack 200 cannot be transferred out of the fuel cell stack 200 in time, resulting in a local temperature rise and increasing the risk of fuel cell stack failure. If the thermal conductivity of the insulating component 3 is greater than 30 W / m·K, the heat transfer rate is faster because the side of the fuel cell stack is close to the short side of the outer casing. Experiments show that this will cause thermal expansion deformation at that location.

[0060] See Figure 8 The battery stack assembly 200, consisting of two battery stacks 20, and the insulating component 3 together divide the receiving cavity into a first cavity 13 and a second cavity 14. The first cavity 13 is connected to the first fluid inlet 11, and the second cavity 14 is connected to the first fluid outlet 12. The first cavity 13 and the second cavity 14 are connected through a first fluid flow channel. Of course, the receiving cavity can also be divided into three cavities by two rows of battery stack assemblies and corresponding insulating components 3, or the receiving cavity can be divided into multiple cavities by multiple rows of battery stack assemblies and corresponding insulating components 3.

[0061] Based on the above structure, the temperature-equalizing hood 1, the fuel cell stack 200, and the insulating component 3 cooperate to form a first cavity 13 and a second cavity 14 inside the temperature-equalizing hood 1. The first fluid required for the electrochemical energy conversion device reaction enters the first cavity 13 through the first fluid inlet 11, then flows into the first fluid channel in the fuel cell stack 20 and enters each single cell in the fuel cell stack 20 for reaction. The cathode exhaust gas after the reaction flows into the second cavity 14 through the first fluid channel in the fuel cell stack 20, and then exits through the first fluid outlet 12. When multiple rows of fuel cell stacks divide the housing into multiple cavities containing intermediate cavities, the first fluid can pass through the aforementioned intermediate cavities before entering the second cavity 14. That is, the first fluid required for the electrochemical energy conversion device reaction does not need to be input and output through the first fluid pipeline, simplifying the process. The overall structure of the electrochemical energy conversion device makes it easier to inspect and disassemble the fuel cell stack 20. Secondly, the temperature equalization hood 1 seals the entire electrochemical energy conversion device, forming a good sealed environment and preventing leakage of the first fluid or the second fluid. The temperature of the first fluid discharged from the fuel cell stack 20 is higher than the temperature of the first fluid input. Due to the presence of the temperature equalization hood 1, the discharged first fluid can fully contact the hood body of the temperature equalization hood 1 and conduct heat to the first cavity 13 through the hood body. This achieves a good temperature equalization effect for the first fluid inside the electrochemical energy conversion device, so that the first fluid entering the temperature equalization hood 1 and the first fluid discharged from the temperature equalization hood 1 after participating in the reaction have similar or the same temperature. This reduces the temperature difference between the first cavity 13 and the second cavity 14, and suppresses the performance degradation and damage of the fuel cell stack caused by local thermal expansion.

[0062] Optionally, such as Figure 8 As shown, in this embodiment, the temperature equalization hood includes multiple walls surrounding the receiving cavity. Let B be the area of ​​the wall where the first fluid inlet 11 is located, and A be the area of ​​the first fluid inlet 11. A / B = 0.01~0.95. If A / B is less than 0.01, the flow rate of the first fluid entering the electrochemical energy conversion device will be high, causing the airflow to tend to supply gas to the fuel cell unit 2 far from the first fluid inlet 11, while the air intake of the fuel cell unit 2 near the first fluid inlet 11 will decrease. This affects the uniformity of the first fluid distribution within the electrochemical energy conversion device, and in severe cases, may cause over-utilization of the first fluid in the fuel cell unit near the first fluid inlet 11, damaging the fuel cell unit. If A / B is greater than 0.95, it will increase the difficulty of sealing the electrochemical energy conversion device with the system platform.

[0063] Optionally, such as Figure 3As shown, in this embodiment, the shape of the first fluid inlet 11 can be any one of regular or irregular shapes such as rectangle, circle, triangle, parallelogram, regular polygon, etc., and is preferably circular. The shape of the first fluid inlet 11 will affect the speed at which the first fluid enters the temperature equalization hood 1. In order to reduce pressure loss, it is preferable to use a circular first fluid inlet 11.

[0064] Optionally, in this embodiment, let C be the distance between the bottom surface of the fuel cell stack 200 and the inner bottom surface of the temperature equalization shroud 1, D be the distance between the top surface of the fuel cell stack 200 and the inner top surface of the temperature equalization shroud 1, E be the distance between the side surface of the fuel cell stack 200 and the corresponding inner side surface of the temperature equalization shroud 1, and F be the thickness of the insulating component 3. Then, C / F = 1~4, D / F = 1~4, and E / F = 1~2. Taking C / F as an example (the others are similar), if C / F is less than 1, the thickness of the insulating component 3 is relatively too large, which increases the cost of using the insulating material, reduces economic efficiency, and affects the assembly of other components with the fuel cell stack 200. If C / F is greater than 4, the thickness of the insulating component 3 is relatively too small. During high-temperature operation, impurity ions in the insulating material will gradually accumulate at both ends under the influence of the electric field. The insulation capacity will decrease with the increase of working time, and in severe cases, insulation failure will occur, leading to breakdown between the fuel cell stack 200 and the temperature equalization shroud 1. When the temperature equalization hood is rectangular, the side of the fuel cell stack 200 is the side of the fuel cell stack 200 closest to the short side of the temperature equalization hood 1. There are only insulating components and some insulating and heat-insulating fillers between the side of the fuel cell stack 200 closest to the short side of the temperature equalization hood and the inner side of the temperature equalization hood 1. Therefore, its ratio is 1 to 2. There are also some other components such as electrical connection plates, lead plates, and gas guiding components between the top and bottom surfaces of the fuel cell stack and the temperature equalization hood. Therefore, its ratio range is relatively large, reaching 1 to 4.

[0065] Optionally, such as Figure 5 As shown, in this embodiment, the electrochemical energy conversion device also includes sealing cotton 4, which is disposed between the insulating component 3 and the temperature equalization cover 1. Therefore, inserting sealing cotton 4 between the insulating component 3 and the temperature equalization cover 1 can, on the one hand, enhance the overall sealing of the electrochemical energy conversion device, preventing leakage of the second fluid and the first fluid; on the other hand, it fills the gap between the insulating component 3 and the temperature equalization cover 1, preventing the insulating component 3 from shaking or misaligning, and providing a certain buffering effect for the fuel cell stack 200 within the electrochemical energy conversion device.

[0066] Optionally, such as Figure 3 and Figure 9As shown, in the present embodiment, the thermal uniform cover 1 is provided with a second fluid inlet hole 16 and a second fluid outlet hole 17. The electrochemical energy conversion device further comprises a second fluid inlet pipe 5 and a second fluid outlet pipe 6. The second fluid inlet pipe 5 is arranged in the first cavity 13 and is connected with the thermal uniform cover 1 through the second fluid inlet hole 16, and is connected with the stack 20. The second fluid outlet pipe 6 is arranged in the second cavity 14 and is connected with the thermal uniform cover 1 through the second fluid outlet hole 17, and is connected with the stack 20. The second fluid inlet pipe 5 and the second fluid outlet pipe 6 comprise a main pipe and a plurality of branch pipes, the main pipe is connected with the thermal uniform cover through the second fluid inlet hole 16 / second fluid outlet hole 17, and is connected with the second fluid flow channel in the stack unit 2 through the branch pipes. The second fluid enters the branch pipes connected with the main pipe of the second fluid inlet pipe 5 from the main pipe, and then is delivered to the stack units 2 in the stack 20 through the branch pipes, and after participating in the reaction in the electrochemical energy conversion device, the second fluid flows into the main pipe of the second fluid outlet pipe 6 from the branch pipes of the second fluid outlet pipe 6, and flows out of the electrochemical energy conversion device. Preferably, the second fluid inlet pipe 5 and the second fluid outlet pipe 6 are both provided with an insulation section. The insulation section is arranged in the middle of the second fluid pipe, so that the whole second fluid pipe is insulated, and the safety performance of the power generation system of the electrochemical energy conversion device is greatly improved.

[0067] Optionally, as Figure 6As shown, in the embodiment, the branch pipe is provided with a fluid equalization device 61, the fluid equalization device 61 has a second fluid exhaust passage and a second fluid intake passage inside, the stack unit bottom plate or the stack unit top plate has a stack unit second fluid intake port and a stack unit second fluid exhaust port, the second fluid exhaust passage is communicated with the stack unit second fluid intake port, and the second fluid intake passage is communicated with the stack unit second fluid exhaust port. Preferably, the end of the fluid equalization device 61 away from the second fluid intake passage and the second fluid exhaust passage is a sealed structure. Based on this, the second fluid enters each fluid equalization device 61 through the main pipe of the second fluid intake pipe 5, and enters the stack unit second fluid intake port in the stack unit top plate or the stack unit bottom plate through the second fluid exhaust passage of the fluid equalization device 61, so as to enter the stack unit to participate in the electrochemical energy conversion device reaction. The second fluid exhaust after the reaction enters the second fluid intake passage in the fluid equalization device 61 through the stack unit second fluid exhaust port in the stack unit top plate or the stack unit bottom plate, and enters the main pipe of the second fluid exhaust pipe 6 through the second fluid intake passage. The design that the second fluid intake / exhaust passage is arranged at one end of the fluid equalization device 61 and the other end is completely sealed can ensure that the amount of the second fluid transported to each stage of the stack unit through the fluid equalization device 61 is relatively uniform, thereby making the amount of the second fluid entering each single cell be relatively small, and improving the utilization rate of the second fluid.

[0068] Optionally, as Figure 8 shown, in the embodiment, the embodiment includes the following implementation manners:

[0069] (1) The temperature equalizing cover 1 includes an end face 15, the second fluid intake hole 16 is arranged on the end face 15, the projection face of the first cavity 13 on the end face 15 is N1, the long side of the projection face N1 is L1, the short side of the projection face N is W1, the projection point of the axis of the second fluid intake pipe 5 on the end face 15 is O1, the distance between the O1 point and the long side L1 is X1, and 0.1W1≤X1≤0.9W1;

[0070] (2) The temperature equalizing cover 1 includes an end face 15, the second fluid exhaust hole 17 is arranged on the end face 15, the projection face of the cavity wall of the second cavity 14 on the end face 15 is N2, the long side of the projection face N2 is L2, the short side of the projection face N2 is W2, the projection point of the axis of the second fluid exhaust pipe 6 on the end face 15 is O2, the distance between the O2 point and the long side L2 is X2, and 0.1W2≤X2≤0.9W2;

[0071] (3) The temperature equalization cover 1 includes an end face 15, a second fluid inlet 16 and a second fluid outlet 17, both of which are opened on the end face 15. The projection surface of the cavity wall of the first cavity 13 on the end face 15 is N1, the long side of the projection surface N1 is L1, the short side of the projection surface N1 is W1, the projection point of the axis of the second fluid inlet pipe 5 on the end face 15 is O1, and the distance between point O1 and the long side L1 is X1. Then 0.1W1≤X1≤0.9W1. The projection surface of the cavity wall of the second cavity 14 on the end face 15 is N2, the long side of the projection surface N2 is L2, the short side of the projection surface N2 is W2, the projection point of the axis of the second fluid outlet pipe 6 on the end face 15 is O2, and the distance between point O2 and the long side L2 is X2. Then 0.1W2≤X2≤0.9W2.

[0072] Since the second fluid conduit is electrically connected to the fuel cell stack 20 via the fluid distribution device 61, and the side of the fuel cell stack 20 opposite to the cavity lacks an insulating component 3, sufficient safety distance needs to be considered between the second fluid conduit and the surfaces containing the long sides of the first cavity 13 and the second cavity 14. When the length X is less than 0.1W or greater than 0.9W, the second fluid conduit is too close to the surfaces containing the long sides of the first cavity 13 and the second cavity 14, which can easily lead to short circuits due to electrical breakdown.

[0073] Optionally, such as Figure 8 As shown, in this embodiment, the temperature equalization hood includes an end face. The projection surface of the first cavity on the end face is N1, the short side of the projection surface N1 is W1, the longest diagonal length of the projection surface N1 is Z1, the projection point of the axis of the second fluid inlet pipe on the end face is O1, the projection of the center point of the first fluid inlet on the end face is P1, and the distance between the P1 point and the O1 point is Y1. Then, 0.1W1≤Y1≤0.85Z1;

[0074] And / or,

[0075] The temperature equalization hood includes an end face. The projection surface of the second cavity on the end face is N2. The short side of the projection surface N2 is W2. The longest diagonal of the projection surface N2 is Z2. The projection point of the axis of the second fluid outlet pipe on the end face is O2. The projection of the center point of the first fluid exhaust port on the end face is point P2. The distance between point P2 and point O2 is Y2. Then 0.1W2≤Y2≤0.85Z2.

[0076] In the present application, the first fluid enters the inside of the uniform temperature cover 1 through the first fluid inlet 11, and during the process of discharging from the electric pile 20 to the first fluid outlet 12, the second fluid pipe is wrapped, so that the temperature difference between the first fluid and the second fluid when entering and discharging the electric pile 20 can be greatly reduced. When Y is equal to 0.1W, it is the shortest distance between the center of the first cavity 13, the second cavity 14 and the center of the second fluid pipe in theory. If Y is less than 0.1W, the second fluid pipe is too close to the uniform temperature cover 1, which is easy to cause electric breakdown and cause safety accidents such as electric leakage. If Y is greater than 0.85Z, the distance between the second fluid pipe and the first fluid inlet 11 and the first fluid outlet 12 is far, which leads to the poor uniform temperature effect between the first fluid and the second fluid, and is easy to cause local thermal expansion.

[0077] Optionally, in the embodiment, the electrochemical energy conversion device further comprises a mounting frame and a heat preservation part. A plurality of electrochemical energy conversion devices are connected together in the electrochemical energy conversion device system to achieve greater power generation efficiency. Since the electrochemical energy conversion device requires a high temperature during operation, a heat preservation part is placed outside the electrochemical energy conversion device for heat insulation, and a mounting frame is assembled outside the heat preservation part to fix the overall structure composed of the plurality of electrochemical energy conversion devices and the heat preservation part. Based on this, the arrangement can ensure that each electrochemical energy conversion device in the electrochemical energy conversion device system forms an independent temperature environment, and the electric pile in each electrochemical energy conversion device has good temperature uniformity, thereby increasing the service life and reliability of the electrochemical energy conversion device system.

[0078] The embodiment of the present application also provides a power generation device comprising the electrochemical energy conversion device. Since the electrochemical energy conversion device is used, the internal space utilization of the power generation device is high, the service life is long, the performance of the electric pile is slow, and the power generation device is convenient to maintain and replace the faulty electric pile.

[0079] In summary, the embodiment of the present application provides an electrochemical energy conversion device which is mainly composed of a uniform temperature cover 1, an electric pile group 200 and an insulation part 3. Compared with the prior art, the present application has the following advantages:

[0080] 1. The first fluid required for the reaction of the electrochemical energy conversion device does not need to be input and discharged through the first fluid pipe, which simplifies the overall structure of the electrochemical energy conversion device and makes it more convenient to maintain and disassemble the electric pile.

[0081] 2. The temperature equalization hood seals the entire electrochemical energy conversion device, creating a good sealed environment and preventing leakage of the first or second fluid. The temperature of the first fluid discharged from the fuel cell stack is higher than the temperature of the first fluid input. Due to the presence of the temperature equalization hood, the discharged first fluid can fully contact the hood body and conduct heat to the first cavity through the hood body. This achieves a good temperature equalization effect on the first fluid inside the electrochemical energy conversion device, making the first fluid entering the temperature equalization hood and the first fluid discharged from the temperature equalization hood after participating in the reaction have similar or the same temperature. This reduces the temperature difference between the first cavity and the second cavity, and suppresses the performance degradation and damage of the fuel cell stack caused by local thermal expansion.

[0082] 3. A row of fuel cells in an electrochemical energy conversion device contains two or more fuel cells. This not only results in a compact structure and high utilization of internal space, but also improves the overall power generation efficiency of the electrochemical energy conversion device. Furthermore, each pair of fuel cells can be electrically connected through a conductive plate, which facilitates the extraction of electrical energy generated by the electrochemical energy conversion device in the same direction, making the overall layout structure more reasonable.

[0083] 4. The electrochemical energy conversion device of the present invention makes full use of the internal space of the temperature equalization hood, and the internal components are arranged in a compact and reliable manner. While ensuring low cost, it improves the utilization rate of the second fluid and the power generation efficiency. It is suitable for actual production, has strong practicality, and is conducive to standardized production and promotion.

[0084] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. An electrochemical energy conversion device, characterized in that, include: A temperature equalization hood having an internal cavity, the temperature equalization hood being made of a thermally conductive material, and the temperature equalization hood having a first fluid inlet and a first fluid outlet. An array of at least one fuel cell stack is disposed within the receiving cavity, wherein the fuel cell stack forms a first fluid flow channel; An insulating component is disposed between the fuel cell stack and the temperature equalization shroud; The fuel cell stack and the insulating component together divide the receiving cavity into multiple cavities, including a first cavity and a second cavity. The first cavity is connected to the first fluid inlet, and the second cavity is connected to the first fluid outlet. The first cavity and the second cavity are connected through the first fluid flow channel. The first fluid discharged from the fuel cell comes into contact with the body of the temperature equalization hood, and the heat is conducted to the first cavity through the hood.

2. The electrochemical energy conversion device as described in claim 1, characterized in that: The thermal conductivity of the temperature equalization hood is 1 ~ 40 W / m·K.

3. The electrochemical energy conversion device as described in claim 1, characterized in that: The thermal conductivity of the insulating component is 1~30 W / m·k.

4. The electrochemical energy conversion device as described in claim 1, characterized in that: The temperature equalization hood includes multiple walls that form the receiving cavity. Let B be the area of ​​the wall with the first fluid inlet and A be the area of ​​the first fluid inlet. A / B = 0.01~0.

95.

5. The electrochemical energy conversion device as described in claim 1, characterized in that: Let C be the distance between the bottom surface of the fuel cell stack and the inner bottom surface of the temperature equalization shroud, D be the distance between the top surface of the fuel cell stack and the inner top surface of the temperature equalization shroud, E be the distance between the side surface of the fuel cell stack and the corresponding inner side surface of the temperature equalization shroud, and F be the thickness of the insulating component. Then C / F = 1~4, D / F = 1~4, and E / F = 1~2.

6. The electrochemical energy conversion device as described in claim 1, characterized in that: The temperature equalization hood is provided with a second fluid inlet and a second fluid outlet. The electrochemical energy conversion device also includes a second fluid inlet pipe and a second fluid outlet pipe; The first cavity is provided with a second fluid inlet pipe, which is connected to the temperature equalization hood through a second fluid inlet hole, and is also connected to the fuel cell stack. The second cavity is provided with a second fluid outlet pipe, which is connected to the temperature equalization cover through a second fluid outlet hole, and is also connected to the fuel cell stack.

7. The electrochemical energy conversion device as described in claim 6, characterized in that: The temperature equalization hood includes an end face. The projection surface of the first cavity on the end face is N1. The long side of the projection surface N1 is L1. The short side of the projection surface N1 is W1. The projection point of the axis of the second fluid inlet pipe on the end face is O1. The distance between point O1 and the long side L1 is X1. Then 0.1W1≤X1≤0.9W1. And / or, The temperature equalization hood includes an end face. The projection surface of the second cavity on the end face is N2. The long side of the projection surface N2 is L2. The short side of the projection surface N2 is W2. The projection point of the axis of the second fluid outlet pipe on the end face is O2. The distance between point O2 and the long side L2 is X2. Then 0.1W2≤X2≤0.9W2.

8. The electrochemical energy conversion device as described in claim 6, characterized in that: The temperature equalization hood includes an end face. The projection surface of the first cavity on the end face is N1. The short side of the projection surface N1 is W1. The longest diagonal length of the projection surface N1 is Z1. The projection point of the axis of the second fluid inlet pipe on the end face is O1. The projection of the center point of the first fluid inlet on the end face is P1. The distance between point P1 and point O1 is Y1. Then 0.1W1≤Y1≤0.85Z1; And / or, The temperature equalization hood includes an end face. The projection surface of the second cavity on the end face is N2. The short side of the projection surface N2 is W2. The longest diagonal of the projection surface N2 is Z2. The projection point of the axis of the second fluid outlet pipe on the end face is O2. The projection of the center point of the first fluid exhaust port on the end face is point P2. The distance between point P2 and point O2 is Y2. Then 0.1W2≤Y2≤0.85Z2.

9. The electrochemical energy conversion device as described in claim 1, characterized in that: The fuel cell stack comprises a plurality of fuel cells, with at least some of the adjacent fuel cells connected in series, and the positive and negative poles of the two fuel cells connected in series are reversed, with the insulating component provided between two adjacent fuel cells.

10. The electrochemical energy conversion device as described in claim 1, characterized in that: It also includes an electrical induction assembly, which includes a conductive part and an electrical connection part. The conductive part is disposed between the insulating component and the fuel cell stack and is electrically connected to the fuel cell stack. The electrical connection part passes through the temperature equalization cover and the insulating component and is connected to the conductive part.

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