CN1937291A - Fuel cell double-sided same-sex electrode array structure and fuel cell system composed thereof - Google Patents

Abstract

The fuel cell double-sided homosexual electrode array structure and the fuel cell system it constitutes relate to a structure of the fuel cell and its stack, which solves the problem that the existing fuel cell body cannot be reduced in size and the surface evenly distributes the flow to a larger area. The problem of cumbersome and low space utilization. A plurality of electrode regions (5) are arranged on the front and back sides of the fuel cell substrate (1) of the present invention, and one metal flow field plate (6) is embedded in each electrode region (5) of the substrate (1), On the front and back sides of the substrate (1), four metal flow field plates (6) are used as a unit array, and the branch flow on the surface of the substrate (1) passes between the four metal flow field plates (6) forming a unit array. Road (8) is connected. The present invention adopts a double-sided homogeneous structure. On the basis of the single-sided electrode of the original flat-plate fuel cell, it makes greater use of space. Especially when working in a self-breathing mode, both sides of the double-sided anode can be in contact with the air. The cathode greatly improves the volume efficiency.

Description

Fuel cell double-sided same-sex electrode array structure and fuel cell system composed thereof

technical field

The invention relates to a structure of a fuel cell and its electric stack, in particular to a double-sided homogeneous electrode structure and a fuel cell system formed thereof.

Background technique

Fuel cells are generally composed of several basic units. Since the voltage that each basic unit can provide is very small, many basic units must be connected in series in order to achieve the required operating voltage output. However, the traditional stacked fuel cell cannot meet the requirement of miniaturization because it needs to connect multiple single cells in series, resulting in too long length. However, the current flat-plate fuel stack uses a single-sided anode plate and a single-sided cathode plate to cooperate. Although the problem of excessive length is solved, a large available space is still fundamentally wasted. Moreover, its feeding and discharging methods still follow the method of stacked fuel cells, which has the problem of poor sealing performance.

Although the Chinese Patent No. 200410074112.8 "Thin Flat-type Direct Methanol Fuel Cell Structure and Its Manufacturing Method" has pointed out the direct methanol fuel cell system and its manufacturing method, there are still the following deficiencies: a) not getting rid of the traditional electricity There is a problem of poor sealing in the way of feeding and discharging the pile. b) There is a possibility of miniaturization by using a single-sided anode. c) The flow field plate cannot be separated from the substrate.

Although Chinese Patent No. 200410055620.1 "Direct Methanol Fuel Cell and Portable Computer with the Battery" has pointed out the direct methanol fuel cell system and its manufacturing method, there are still the following deficiencies: a) the single-sided electrode is still used, There is a possibility of miniaturization. b) The average distribution channel on the surface is cumbersome and may be simplified. c) Only two corresponding substrates are included, and the number of single cells can only be increased within the planar area of the substrate.

Although the Chinese Patent No. 01815152.3 "Direct Methanol Fuel Cell System" has pointed out the direct methanol fuel cell system and manufacturing method, there are still the following deficiencies: a) There is a possibility of miniaturization by using a single-sided anode. b) The design of the microfluidic pipeline will cause difficult processing and difficult mass production. c) Due to the simple design that the feeding and discharging channels are all in the substrate, when there are many monomers, there are difficulties in the design of the feeding and discharging ports, resulting in complicated processing and difficult batch processing. There are possibilities for simplification. d) It only points out that the cooperation of a single anode substrate and a cathode substrate is not high in space utilization.

Contents of the invention

In order to solve the problems that the existing fuel cell body can no longer be reduced in size, the average surface distribution channel is cumbersome, and the space utilization rate is low, the present invention proposes a fuel cell double-sided homogeneous electrode array structure and a fuel cell system composed of it . The invention is applicable to the direct type fuel cell in which methanol, dimethyl ether, ethanol, formic acid and hydrogen are used as fuel.

The fuel cell double-sided same-sex electrode array structure of the present invention is composed of a substrate, a plurality of electrode regions and a plurality of metal flow field plates; the substrate is provided with a circle of assembly through holes at the edge; the electrode regions are formed on the On the front and back of the substrate, one metal flow field plate is inlaid in each electrode area of the substrate, and four metal flow field plates are used as a unit array on the front and back of the substrate to form a unit array. The four metal flow field plates are connected through the surface branch channel of the substrate, and a feed outlet hole is opened in the area of the surface branch channel of each unit array, and the feed outlet hole passes through the main feed channel set on the substrate It communicates with the outside of the substrate. Each electrode area is provided with a conductive hole and a discharge hole. Each conductive hole communicates with the outside of the substrate through a wire lead-out channel provided on the substrate. Each discharge hole passes through The main discharge channel provided on the base plate communicates with the outside of the base plate. The depth of the electrode region formed on the surface of the substrate is consistent with the thickness of the metal flow field plate. The metal flow field plate is embedded in the electrode area, and a sealing silicone gasket is sandwiched between the metal flow field plate and the electrode area for sealing.

A fuel cell system composed of the above-mentioned multiple double-sided electrode array structures, which includes multiple integrated double-sided cathode systems, multiple integrated double-sided anode systems, multiple three-in-one membrane electrode assemblies and two terminal Internally integrated unipolar electrode system; each integrated double-sided cathode system uses the above-mentioned double-sided same-sex electrode array structure and the metal flow field plates on the front and back sides of the substrate are cathodes, and each integrated double-sided anode system uses the above-mentioned The structure of the double-sided same-sex electrode array system and the metal flow field plates on the front and back sides of the substrate are anodes, and multiple integrated double-sided cathode systems and multiple integrated double-sided anode systems are stacked in sequence to form a fuel cell stack; multiple three-in-one A membrane electrode assembly is located between two adjacent integrated double-sided cathode systems and integrated double-sided anode systems, and each electrode area is equipped with a three-in-one membrane electrode assembly; set at both ends of the fuel cell stack There is an end-integrated unipolar electrode system, and the end-integrated unipolar electrode plate only has the electrode area and metal flow on one surface in the integrated fuel cell system composed of the above-mentioned double-sided electrode array structure. The structure of the field plates and their associated holes and channels, the polarity of which is determined by the polarity of the two end faces of the formed fuel cell stack; The integrated double-sided cathode system, integrated double-sided anode system and end-integrated monopolar electrode system.

Effects of the invention: The present invention is a fuel cell structure with a double-sided homogeneous electrode array and a special feed and discharge design, which provides a fuel cell system with a double-sided homogeneous electrode array. The single fuel cell with double-sided homogeneous electrode array structure of the present invention has independent main channels respectively arranged on the front and back sides of the substrate. The fuel cell of the present invention adopts double-sided isotropic structure. On the basis of the single-sided electrode of the original flat-plate fuel cell, more space is used. Especially when working in the self-breathing mode, both sides of the double-sided anode can be connected with The cathode in air contact greatly improves the volume efficiency; the method of cooperating with the main channel in the substrate and the sub-channel on the surface not only facilitates processing, solves the problem of evenly distributing the fuel, but also solves the problem that all the channels are on the surface to a certain extent. The sealing problem caused by it; get rid of the form of only single-layer anode in the traditional flat-plate fuel cell, it can be made thinner according to the requirements, and the number of double-sided electrodes of the same sex can be increased according to the needs, so as to improve the power.

Description of drawings

Fig. 1 is the three-dimensional schematic diagram of double-sided same-sex electrode array structure of the present invention; Fig. 2 is the front view of the substrate in Fig. 1; Fig. 3 is the top view of the substrate in Fig. 1; Fig. 4 is the rear view of the substrate in Fig. 1; Fig. 5 is a bottom view of the substrate in FIG. 1; FIG. 6 is a cross-sectional view of A-A of FIG. 3; FIG. 7 is a front view of the substrate structure in an end-integrated unipolar electrode plate; FIG. 8 is a top view of FIG. 7; Figure 10 is a bottom view of Figure 7; Figure 11 is a schematic diagram of a three-dimensional structure of a metal flow field plate 6; Figure 12 is a schematic structural diagram of a substrate 1 containing multiple cell arrays; Schematic diagram of the assembly of the fuel cell system with isotropic electrode array structure.

In the above figure, 1—base plate; 2—assembly hole; 3—main discharge channel; 4—leading wire channel; 5—electrode area; 6—metal flow field plate; 7—feeding and exporting hole; 8—surface branch channel ; 9—main feeding channel; 5-1—conductive hole; 5-2—discharging hole; 6-1—fuel introduction channel; 6-2—metal edge; 6-3—flow channel; 11—integrated double-sided anode system; 12—end integrated monopolar system; 13—three-in-one membrane electrode assembly.

Detailed ways

Specific embodiment 1: Referring to Fig. 1 to Fig. 6, the double-sided homogeneous electrode array body of this specific embodiment is composed of a substrate 1, four cathode electrode regions 5 and four metal flow field plates 6; the substrate 1 is at the edge A circle of assembly through holes 2 is provided at the part; the electrode area 5 is formed on the front and back sides of the substrate 1 by machining, and one metal flow field plate 6 is embedded in each electrode area 5 of the substrate 1, On the front and back sides of the substrate 1, four metal flow field plates 6 are used as a unit array, and the four metal flow field plates 6 forming a unit array are connected through the surface branch channel 8 of the substrate 1, and each unit A feed outlet hole 7 is opened in the area of the surface branch channel 8 of the array, and the feed outlet hole 7 communicates with the outside of the substrate 1 through the main feed channel 9 provided on the substrate 1, and in each electrode area 5 All are provided with a conductive hole 5-1 and a discharge hole 5-2, each conductive hole 5-1 communicates with the outside of the substrate 1 through a wire lead-out channel 4 provided on the substrate 1, and each discharge hole 5- 2 communicates with the outside of the substrate 1 through the main discharge channel 3 provided on the substrate 1. The depth of the electrode region 5 formed on the surface of the substrate 1 is consistent with the thickness of the metal flow field plate 6 . As shown in Figures 1 to 6, only one structure diagram of the above-mentioned unit array structure on the substrate 1 is shown in the figure. As shown in Figure 12, multiple unit array structures can also be arranged on the substrate 1 along the vertical or horizontal direction. Then, the internal and external passages provided by the substrate for each unit structure are the same as those shown in FIGS. 1 to 6 .

The substrate 1 is made of non-conductive materials, such as insulating materials such as PTFE (polytetrafluoroethylene) or ABS (engineering plastics), or it is used not only as a supply and discharge channel for fuel and gas, but also as a carrier and a carrier of the anode and cathode flow fields. The shell and support body of the electric stack. Referring to Fig. 2 to Fig. 6, each main feed channel 3 is designed in the base plate 1, and when reaching the collection portion of the corresponding electrode area, it communicates with the discharge hole 5-2, and the discharge hole 5-2 is used for For the export of fuel or gas, and re-process the two or single surfaces of the substrate 1 to evenly distribute the flow path, so that the fuel or gas can evenly flow to each anode or cathode area. The single cell is suitable for direct type fuel single cell with methanol, dimethyl ether, ethanol, formic acid and hydrogen as fuel.

As shown in Figure 6, each electrode area is equipped with a separate conductive lead-out channel to electrically connect each monomer outside the stack, which is convenient for the use of different voltages and currents, meets the requirements of the actual working environment, and is convenient for the stack fault detection and removal.

As shown in FIG. 1 , the metal flow field plate 6 is embedded in the electrode area 5 , and a sealing silicone pad is sandwiched between the metal flow field plate 6 and the electrode area 5 for sealing. The metal flow field plate 6 is made of metal materials such as stainless steel, and the surface is electroplated as a conductive coating, and embedded in the corresponding electrode area 5 . As shown in Figure 11, each metal flow field plate 6 has the following structural features: a plurality of interconnected flow channels 6-3 are opened on the upper surface of the flow field plate plated with nickel-gold coating on the surface, and adjacent flow channels Metal ribs 6-2 are formed between the channels 6-3, and the interconnected flow channels 6-3 communicate with the fuel introduction channel 6-1 and also communicate with the surface branch channel 8 of the single fuel cell. The surface branch channel 8 can be designed as a rectangular structure as shown in FIG. 2 . The thickness of the metal flow field plate 6 depends on specific conditions, and the type of the flow channel can be selected according to the specific working conditions. The processing of the flow channel 6-3 can be done by CNC lathe processing or forging, electrochemical corrosion, electric spark cutting and other means. The depth of the flow channel 6-3 can be selected from 1mm to 5mm, and the width of the flow channel 6-3 can be selected from 1mm to 5mm.

Specific embodiment two: Referring to Fig. 1 to Fig. 13, the fuel cell system composed of the double-sided homogeneous electrode array structure described in specific embodiment one includes a plurality of integrated double-sided cathode systems 10, a plurality of integrated Double-sided anode system 11, a plurality of three-in-one membrane electrode assemblies 13 and two end-integrated unipolar electrode systems 12; each integrated double-sided cathode system 10 adopts the double-sided same-sex electrodes described in the first embodiment The structure of the array system and the metal flow field plate 6 on the front and back of the substrate 1 are cathodes, and each integrated double-sided anode system 11 adopts the structure of the double-sided homogeneous electrode array system described in the first embodiment, and the front and back of the substrate 1 The metal flow field plates 6 on both sides are anodes, and multiple integrated double-sided cathode systems 10 and multiple integrated double-sided anode systems 11 are sequentially stacked to form a fuel cell stack; multiple three-in-one membrane electrode assemblies 13 are located on two adjacent Between the integrated double-sided cathode system 10 and the integrated double-sided anode system 11, and each electrode area is equipped with a three-in-one membrane electrode assembly 13; at both ends of the formed fuel cell stack are respectively provided with an end integrated The unipolar electrode system 12, the end-integrated unipolar electrode plate 12 only has the electrode area on one surface, metal The structure of the flow field plates and their associated holes and channels, the polarity of which is determined by the polarity of the two end faces of the formed fuel cell stack; utilizing fasteners passing through the mounting holes 2 of the respective base plates 1 All the integrated double-sided cathode systems 10, integrated double-sided anode systems 11 and end-integrated monopolar electrode systems 12 are fixedly connected. The fuel cell system is suitable for direct type fuel cells with methanol, dimethyl ether, ethanol, formic acid and hydrogen as fuel. In normal use, the base plate 1 adopts the mode of laying flat.

7 to 9 show a structure of a substrate 1 including an end-integrated monopolar electrode system 12 with a cell array structure, in which vertical surface branch channels are used. Using the assembly method shown in Figure 13, the volume of the stack can be adjusted according to specific requirements. If thinning is required, a double-sided anode or double-sided cathode system and a single-sided anode and cathode system can be used to assemble a thin stack system , and use ABS and other thin sheets as substrates, which can be used in mobile electronic products such as notebooks and mobile phones. When high power is required and the requirement for mobility is not high, multiple double-sided anode and double-sided cathode systems can be used, plus a set of single-sided anode and single-sided cathode systems on the end face, and a stack system with a high success rate can be assembled. .

Claims (8)

1, fuel cell even-side electrode array structure is characterized in that described monocell is made of substrate (1), a plurality of electrode zone (5) and a plurality of metal flow field plate (6); Described substrate (1) is provided with a circle assembling through hole (2) in the edge; Described electrode zone (5) is formed at the tow sides of described substrate (1), be inlaid with a described metal flow field plate (6) in each electrode zone (5) of described substrate (1), tow sides at described substrate (1) are a cell array with four metal flow field plates (6), surperficial branch flow passage (8) by substrate (1) between four metal flow field plates (6) of a cell array of formation is connected, have a charging leadout hole (7) in the zone of the surperficial branch flow passage (8) of each cell array, this charging leadout hole (7) is gone up the main feeding-passage (9) that is provided with by substrate (1) and is connected with the outside of substrate (1), in each electrode zone (5), all be provided with a conductive hole (5-1) and a relief hole (5-2), each conductive hole (5-1) is gone up the lead extraction channel (4) that is provided with by substrate (1) and is connected with the outside of substrate (1), and each relief hole (5-2) is gone up the main discharging channel (3) that is provided with by substrate (1) and is connected with the outside of substrate (1).

2, fuel cell even-side electrode array structure according to claim 1 is characterized in that described substrate (1) adopts electrically non-conductive material.

3, fuel cell even-side electrode array structure according to claim 1, it is characterized in that described metal flow field plate (6) adopts metal materials such as stainless steel, and electroplate as conductive coating, and be embedded in the corresponding electrode zone (5) on the surface.

4, fuel cell even-side electrode array structure according to claim 1 is characterized in that the described degree of depth of the surperficial electrode zone (5) of described substrate (1) and the consistency of thickness of metal flow field plate (6) of being formed at.

5, fuel cell even-side electrode array structure according to claim 1 is characterized in that described electrode zone 5 is formed at the tow sides of described substrate (1) with machining.

6, fuel cell even-side electrode array structure according to claim 2 is characterized in that described electrically non-conductive material is PTFE or ABS.

7, according to claim 1,2,3,4 or 5 described fuel cell even-side electrode array structures, it is characterized in that described metal flow field plate (6) be embedded in the electrode zone (5) and described metal flow field plate (6) and electrode zone (5) between accompany the sealed silicon rubber cushion and seal.

8, the fuel cell system that is made of the described fuel cell even-side of claim 1 electrode array structure is characterized in that described fuel cell system includes a plurality of integrated two-sided cathod systems (10), a plurality of integrated two-sided anode systems (11), a plurality of three in one membreane electrode assembly (13) and two integrated unipolarity electrode systems in end (12); Each integrated two-sided cathod system (10) adopt the described even-side electrod-array of embodiment one system structure and the double-edged metal flow field plate of substrate (1) (6) be negative electrode, it be anode that each integrated two-sided anode system (11) adopts the structure and the double-edged metal flow field plate of substrate (1) (6) of the described even-side electrod-array of embodiment one system, a plurality of integrated two-sided cathod systems (10) and a plurality of integrated two-sided anode systems (11) the formation fuel cell pack that superposes successively; A plurality of three in one membreane electrode assemblies (13) are positioned between adjacent two integrated two-sided cathod systems (10) and the integrated two-sided anode system (11), and each electrode zone configuration three in one membreane electrode assembly (13); Two ends at the fuel cell pack that constitutes are respectively arranged with an integrated unipolarity electrode system in end (12), the integrated unipolarity electrode system in this end (12) only has in the integrated fuel cell system that the described even-side electrode array structure of claim 1 constitutes and relates to electrode zone, metal flow field plate and the associated orifices thereof of a face and the structure of passage, and the polarity of this unipolarity battery lead plate is by the polarity decision of two end faces of the fuel cell pack that constitutes; The fixedly connected all integrated two-sided cathod systems (10) of securing member, integrated two-sided anode system (11) and the integrated unipolarity electrode system in end (12) of the pilot hole (2) of each substrate (1) passed in utilization.

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