CN214280023U

CN214280023U - Fuel cell subregion composite sheet forming device

Info

Publication number: CN214280023U
Application number: CN202120304560.1U
Authority: CN
Inventors: 李丽; 甘全全; 戴威
Original assignee: Shanghai Shen Li High Tech Co Ltd
Current assignee: Shanghai Shenli Technology Co Ltd
Priority date: 2021-02-03
Filing date: 2021-02-03
Publication date: 2021-09-24
Anticipated expiration: 2031-02-03

Abstract

The utility model relates to a fuel cell subregion composite sheet forming device, including loading mould (1) and forming die (2), wherein load mould (1) and be equipped with the filling area who loads reaction zone composite sheet and non-reaction zone composite sheet powder respectively, be equipped with fuel cell polar plate die cavity on forming die (2). Compared with the prior art, the utility model discloses the device has realized the different material integrated into one piece of same polar plate, and fundamentally improves and has balanced sealed, and the relation of electrically conductive, intensity weakens external power generation loss, has improved the reliability of galvanic pile.

Description

Fuel cell subregion composite sheet forming device

Technical Field

The utility model relates to a fuel cell especially relates to a fuel cell subregion composite sheet forming device.

Background

With the gradual maturity of fuel cell technology, the fuel cell is used as a zero-pollution and high-efficiency power generation device capable of directly converting chemical energy into electric energy, and is increasingly applied to the fields of communication relay stations, vehicle-mounted power, distributed power supplies and the like.

The bipolar plate is one of the core components of a fuel cell, and plays a role in distributing gas, conducting heat and electric energy. With the gradual increase of the volume power density requirement of the electric pile, the thinning of the bipolar plate and the membrane electrode becomes a necessary trend.

The bipolar plates at present mainly include metal bipolar plates, graphite bipolar plates, and bipolar plates of a multi-layer material using two materials at the same time. The graphite bipolar plate formed by the mixed material die-casting method is considered to be the process which has the most accurate forming size and can completely meet the requirements of sealing, electric conduction and the like.

In the presently disclosed data on graphite bipolar plates, uniform materials, such as mixed condensates of graphite and resin and additives, are used for the preparation of the bipolar plates. In order to ensure the electrical and thermal conductivity of the material, the resin content in the mixture is relatively low, which results in relatively weak strength, and cannot meet the requirement of high strength in some non-conductive parts of the bipolar plate. However, as the requirement for thinning of the bipolar plate is more and more demanding, these portions with higher strength become bottlenecks that limit the graphite bipolar plate.

It has been found through current patent inquiry that patents have focused primarily on composite plate material formulations, such as CN108511764A, and on the direct modification of bipolar plate substrate materials, such as CN110581291A silicon, for fuel cell applications. The relation of sealing, electric conduction and strength is improved and balanced in a certain layer. It does not fundamentally solve the bottleneck problem of the material.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a fuel cell subregion composite sheet forming device in order to overcome the defect that above-mentioned prior art exists, can be with the powder integrated into one piece of at least two kinds of differences for the fuel cell polar plate.

The purpose of the utility model can be realized through the following technical scheme: the fuel cell partition composite board forming device comprises a filling mold and a forming mold, wherein the filling mold is provided with a filling area for filling powder of a reaction area composite board and a non-reaction area composite board respectively, and a fuel cell polar plate mold cavity is formed in the forming mold.

The filling mould consists of a movable bottom plate and a blade separator;

the movable bottom plate consists of a partition block, a partition block strut and a base, wherein two ends of the partition block strut are respectively and fixedly connected with the partition block and the base;

the blade separator is provided with a reaction powder filling area, a non-reaction powder filling area, a blade and a separator bottom frame, wherein the reaction powder filling area is matched with the fuel cell polar plate reaction area, the non-reaction powder filling area is matched with the fuel cell polar plate non-reaction area, the blade is arranged on the separator bottom frame, and the root of the blade is tightly fit with the bottom of the forming mold.

The blade is less than 0.1mm thick, is made of high-strength materials and comprises die steel.

The size and the shape of the dividing block are matched with the blade separator, when the cutting device is used, the dividing block is embedded into the blade separator, the matching gap between the blade separator and the dividing block is 0.02-0.05 mm, and powder can be effectively prevented from being penetrated out from a gap.

The forming die comprises a forming lower die and a die assembly positioning pin, and the filling die is provided with a positioning hole matched with the die assembly positioning pin.

The method for preparing the composite board by adopting the forming device comprises the following steps:

1) mounting a blade separator on a forming die, filling the composite board powder in the reaction area in the reaction powder filling area, compacting the powder, filling the composite board powder in the non-reaction area in the non-reaction powder filling area, and compacting the powder; the powder filling height does not exceed the upper edge of the blade separator.

2) Mounting a movable bottom plate on the blade separator, embedding the dividing blocks into the blade separator and compacting again;

3) and under the condition of keeping the movable bottom plate not to move, slowly lifting the blade separator to separate the blade separator, and removing the blade separator and the movable bottom plate to finish the feeding process.

Through the forming device, at least two different powder materials can be respectively filled in a forming die according to the reaction characteristics of the polar plate, and integrated compression molding is carried out, so that the obtained polar plate can achieve the purpose that the performances of all regions on the same polar plate are different, for example, the polar plate is divided into a reaction region and a non-reaction region, different formulas are respectively filled in the powder material filling regions corresponding to the die for compression molding, the strength of the obtained polar plate reaction region composite plate is 20-50MPa, the resistance is 10-50 mu omega.m, and the sealing characteristic is not more than 0.02 SCCM. The strength of the composite board in the non-reaction area is 50-100 MPa.

Compared with the prior art, the utility model discloses following beneficial effect has:

1. the utility model discloses according to the regional characteristic design subregion forming device of fuel cell polar plate, load the polar plate material of different formulas, make the fuel cell polar plate, make the polar plate realize the high strength in non-conductive region, do not consider electrically conductive requirement, and maintain the low resistance in reaction zone, relative low strength and sealing characteristic, fundamentally improves and has balanced sealed, the relation of electrically conductive, intensity.

2. The utility model discloses the powder that the device can be used divide into more than 2, and the important difference between each share is that graphite content (promptly resin content) is different. The part with the highest graphite and conductive material content (generally the lowest resin content) is used for preparing the active area of the electrode plate, and the part with the lowest graphite and conductive agent content is used for preparing the outer edge of the active area of the electrode plate so as to improve the strength requirement. The hot melting characteristics of the resins used among the powder materials are similar to ensure that the melting temperatures are the same. The powder materials are loaded into different areas of a die pressing die by using a special filling tool. And after further leveling, finishing the subsequent preparation process, such as die assembly, heating and demoulding, and finally realizing the polar plate with the material partitioned.

3. The utility model discloses the bipolar plate that forms is the further subdivision of regional function, generally speaking, and the gap bridge part at bipolar plate port and flow field looks UNICOM requires higher to intensity the utility model discloses in make this part material intensity can increase substantially because of need not consider conductive factor to reduce this part thickness, and then reduce whole bipolar plate thickness, the thickness of bipolar plate can reduce to 0.5-1.0mm, and the ordinary graphite plate thickness of equal intensity is 1.0-2.0 mm.

4. Non-conductive materials are used in the port area, short-distance bridging of adjacent bipolar plates in the port due to reaction water or cooling liquid is fundamentally solved after the galvanic pile is formed, and external power generation loss is avoided and weakened;

5. the non-conductive material is used on the outer edge of the polar plate, when the electric pile is assembled, the isolation between the adjacent bipolar plates can be avoided, the short circuit phenomenon can not be caused, and the reliability of the electric pile is greatly improved. This makes the pile itself have IP67 characteristic, and no extra external package design is needed.

6. The utility model discloses forming device simple structure, convenient operation, the shaping is effectual.

Drawings

Fig. 1 is a schematic structural view of the composite board of the present invention;

FIG. 2 is a top view of the blade divider;

FIG. 3 is a perspective view of the blade divider;

FIG. 4 is a schematic structural view of the movable base plate;

FIG. 5 is a schematic view of an upper mold structure formed by the combination of the movable base plate and the blade divider;

FIG. 6 is a schematic structural view of the upper mold and the lower mold in a separated state;

FIG. 7 is a schematic view of a mold closed state;

FIG. 8 is a schematic view showing a mold released state after mold clamping.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Example 1

The utility model provides a fuel cell subregion composite sheet forming device, according to the characteristic of fuel cell polar plate, divide into reaction zone and non-reaction zone with the polar plate, adopts the powder of two kinds of different prescriptions as the raw materials in fuel cell polar plate reaction zone and non-reaction zone respectively, through the compression molding of mould shaping method, the composite sheet after the shaping includes reaction zone composite sheet and non-reaction zone composite sheet, wherein reaction zone composite sheet powder A prescription includes following part by weight component: 70 parts of graphite powder, 5 parts of carbon fiber, 20 parts of resin and 5 parts of conductive carbon black;

the formula of the raw material powder B of the non-reaction zone composite board comprises the following components in parts by weight: 10 parts of graphite powder, 10 parts of short carbon fiber and 80 parts of resin.

For the integral molding of the reaction region and the non-reaction region, a mold, as shown in fig. 1 to 8, may be used for molding, the mold including an upper mold, which is a filling mold 1, and a lower mold, which is a molding mold 2.

The filling mould 1 is provided with filling areas for respectively filling powder of a reaction area composite plate and a non-reaction area composite plate, and the filling mould 1 consists of a movable bottom plate 11 and a blade separator 12; as shown in fig. 2-4;

the movable bottom plate 11 is composed of a partition block 111, a partition block support 112 and a base 113, wherein two ends of the partition block support 112 are respectively fixedly connected with the partition block 111 and the base 113; as shown in fig. 4; the dividing block 111 is provided with a cavity matched with the polar plate reaction area and an inlet and an outlet matched with the inlet and the outlet of the fluid on the polar plate.

The blade separator 12 is provided with a reactive powder filling area 121, a non-reactive powder filling area 122, a blade 123 and a separator bottom frame 124, wherein the reactive powder filling area 121 is matched with the fuel cell pole plate reaction area, the non-reactive powder filling area 122 is matched with the fuel cell pole plate non-reaction area, the blade 123 is arranged on the separator bottom frame 124, and the root of the blade is tightly fit with the bottom of the forming mold 2. The blade 123 is less than 0.1mm thick and made of high-strength material, including die steel. As shown in fig. 2-3;

the size and the shape of the dividing block 111 are matched with those of the blade separator 12, when the cutter is used, the dividing block 111 is embedded into the blade separator 12, the matching gap between the blade separator 12 and the dividing block 111 is 0.02-0.05 mm, and powder can be effectively prevented from being penetrated out from the gap. (as shown in FIG. 5)

The forming die 2 comprises a forming lower die 21 and die assembly positioning pins 22, the forming lower die 21 is provided with a fuel cell polar plate die cavity, the die assembly positioning pins 22 are at least two and symmetrically arranged at opposite angles on the upper surface of the forming lower die 21, and the filling die 1 is provided with positioning holes matched with the die assembly positioning pins. (as shown in FIG. 6)

1, installing a blade separator 12 on a forming die 2, filling reaction zone composite board powder A in a reaction powder filling zone 121, and compacting the powder, wherein the powder filling height does not exceed the upper edge of the blade separator 12, and similarly, installing non-reaction zone composite board powder B in a non-reaction powder filling zone 122, and compacting the powder;

2, mounting a movable bottom plate 11 on the blade separator 12, and embedding the dividing blocks 111 into the blade separator 12 for compressing again;

3, slowly lifting the blade separator 12 under the condition that the movable bottom plate 11 does not move, separating the blade separator 12, and removing the blade separator 12 and the movable bottom plate 11 to finish the feeding process.

The resulting composite plate structure is shown in fig. 1, and includes a plate non-reaction zone F and a plate reaction zone T.

Example 2

A fuel cell partition composite board forming device comprises a reaction region composite board and a non-reaction region composite board, wherein the powder formula of the reaction region composite board comprises the following components in parts by weight: 60 parts of graphite powder, 8 parts of carbon fiber, 25 parts of resin and 8 parts of conductive carbon black;

the powder formula of the composite board in the non-reaction area comprises the following components in parts by weight: 5 parts of graphite powder, 5 parts of short carbon fiber and 90 parts of resin.

The rest is the same as example 1.

Example 3

A fuel cell partition composite board forming device comprises a reaction region composite board and a non-reaction region composite board, wherein the powder formula of the reaction region composite board comprises the following components in parts by weight: 80 parts of graphite powder, 1 part of carbon fiber, 15 parts of resin and 1 part of conductive carbon black;

the powder formula of the composite board in the non-reaction area comprises the following components in parts by weight: 15 parts of graphite powder, 15 parts of short carbon fiber and 70 parts of resin.

The rest is the same as example 1.

The polar plate obtained in the above embodiment was subjected to a performance test, and the results were as follows:

。

Claims

1. the fuel cell partition composite board forming device is characterized by comprising a filling mould (1) and a forming mould (2), wherein the filling mould (1) is provided with a filling area for filling powder of a reaction area composite board and a non-reaction area composite board respectively, and the forming mould (2) is provided with a fuel cell polar plate mould cavity.

2. The fuel cell partition composite plate molding device according to claim 1, wherein the filling mold (1) is composed of a movable bottom plate (11) and a blade separator (12).

3. The fuel cell partition composite plate forming device according to claim 2, wherein the movable bottom plate (11) is composed of a partition block (111), a partition block pillar (112) and a base (113), and both ends of the partition block pillar (112) are respectively fixedly connected with the partition block (111) and the base (113).

4. The forming device of the fuel cell partition composite board according to claim 2, wherein the blade separator (12) is provided with a reactive powder filling area (121), a non-reactive powder filling area (122), a blade (123) and a divider chassis (124), wherein the reactive powder filling area (121) is matched with the fuel cell plate reactive area, the non-reactive powder filling area (122) is matched with the fuel cell plate non-reactive area, and the blade (123) is arranged on the divider chassis (124) and the root thereof is tightly sealed with the bottom of the forming mold (2).

5. The fuel cell segmented composite plate forming device according to claim 4, wherein the thickness of the blade (123) is less than 0.1 mm.

6. The fuel cell segmented composite plate forming device according to claim 3, wherein the segment (111) is matched in size and shape to the blade separator (12).

7. The fuel cell partition composite plate forming device according to claim 3, wherein the partition block (111) is embedded in the blade separator (12) during molding, and the fit clearance between the blade separator (12) and the partition block (111) is 0.02-0.05 mm.

8. The forming device of the fuel cell partition composite board according to claim 1, wherein the forming mold (2) comprises a lower forming mold (21) and a mold closing positioning pin (22), and the filling mold (1) is provided with a positioning hole matched with the mold closing positioning pin.