CN220856630U - Integrated connection structure of fuel cell stack - Google Patents

Abstract

The utility model discloses an integrated connection structure of a fuel cell stack. The device comprises a series connection structure and a parallel connection structure, wherein the series connection structure comprises a universal rear end plate, a series connection front end plate, a stacked single cell group and a pile distribution cavity; the connection mode between the stacked single cell groups is series connection; the stacked cell stack includes a forward stacked cell stack and a reverse stacked cell stack. The parallel connection structure comprises a general rear end plate, a forward stacked single cell group, a pile distribution cavity, a parallel current collecting plate and a parallel front end plate. Grooves for embedding parallel current collecting plates are formed in the parallel front end plate and the universal rear end plate, and the parallel current collecting plates are embedded in the grooves; a forward stacking single cell group is arranged between the parallel front end plate and the universal rear end plate; the pile distribution chamber is fixed on the parallel front end plate. By the scheme of the utility model, the power of the single fuel cell stack module can be improved, and the requirement of a high-power fuel cell system can be met.

Description

Integrated connection structure of fuel cell stack

Technical Field

The utility model belongs to the field of fuel cells, relates to a fuel cell stack integrated connection structure, and in particular relates to a fuel cell stack integrated serial and parallel connection structure.

Background

Currently, high-power fuel cell systems on the market are limited by the power limit of a single stack, so that two stacks are adopted on the system to be connected in series through a transfer copper plate. In the prior art, the anode and cathode current collecting plate lugs of the fuel cell are distributed on two opposite sides of the electric pile, so that in the structural design process of the system, anode and cathode copper plates are required to be switched to the same side and connected to a main output electric interface of the system, but one of the anode and cathode copper plates is required to be switched for a long distance. Currently, in order to assemble a fuel cell system with a dual stack assembly, a crane is required to assemble the dual stacks together and then hoist them into a system box.

In the prior art, in the galvanic pile production process, an automatic stacking robot stacks bipolar plates and membrane electrodes alternately to corresponding positions of end plates. After the pile is stacked, the pile is pressed by a press and then fastened by a steel belt. The process only produces one pile at a time, and double piles can not be stacked simultaneously and fastened steel belts can not be pressed synchronously. The prior art has the following problems: 1. the existing single pile has low power, and is difficult to meet the requirements of high-power electric piles; 2. the existing single pile has low production efficiency; 3. in the existing double-stack scheme, the current collecting plates are connected through copper bars, so that the connection impedance between two stacks is increased. 4. The active area of the existing pile is fixed, and the current output by the pile cannot be changed under the rated current density of the pile.

Disclosure of utility model

The utility model provides an integrated connecting structure of a fuel cell stack, which can directly mount a fixed bracket into a system box without double-stack assembly steps, and simplifies the system assembly process.

The object of the utility model is achieved by at least one of the following technical solutions.

A fuel cell stack integrated connection structure comprises a general rear end plate, a serial front end plate, a stacked single cell group and a stack distribution cavity;

the connection mode between the stacked single cell groups is series connection; the stacked cell group includes a forward stacked cell group and a reverse stacked cell group;

Grooves are formed in the universal rear end plate and the serial front end plate; the serial connection rear current collecting plate is embedded in a groove formed in the universal rear end plate, and the serial connection front current collecting plate is embedded in a groove formed in the serial connection front end plate; the forward stacking single cell group and the reverse stacking single cell group are arranged between the universal rear end plate and the serial front end plate, and the stacking directions of the forward stacking single cell group and the reverse stacking single cell group are opposite; the stack distribution chambers are fixed to the front end plates in series.

Further, the forward stacked cell group and the reverse stacked cell group are fixed with a common rear end plate and a serial front end plate by steel belts.

Further, the utility model also comprises a collector plate insulating plug; the collector plate insulating plug is fixed on a notch on the universal rear end plate.

Further, the stack distribution chambers are located on the front end plates in series in opposite directions.

Further, the number of the front current collecting plates in series is 2, and the two front current collecting plates in series are embedded into the corresponding grooves of the front end plates in series.

Because the fuel cell stack serial connection design scheme adopts two groups of fuel cell stacks with opposite stacking directions, electrons reacted by the electric stack are conducted onto the forward stacking single cell stack from the reverse stacking single cell stack through the serial connection rear current collecting plates by adjusting the stacking directions and the sequence of the cathodes and the anodes of the forward stacking single cell stack, then the upper front current collecting plate and the lower front current collecting plate which are connected in series respectively form the anodes and the cathodes of the electric stack, and the electrons are definitely formed into a serial circuit by connecting an external circuit load. The technical scheme can cope with the application scene of high voltage and low current, and the switching copper plate and the copper plate fixing device can be omitted by adopting the scheme, so that the connection impedance between electric stacks is effectively reduced while the structure of the fuel cell is simplified, the power of a single fuel cell stack module can be improved, and the requirement of a high-power fuel cell system is met.

The utility model relates to an integrated connection structure of a fuel cell stack, wherein a cell stack adopts a parallel connection mode, and the structure comprises a general rear end plate, a forward stacked single cell stack, a cell stack distribution cavity, a parallel current collecting plate and a parallel front end plate;

Grooves for embedding parallel current collecting plates are formed in the parallel front end plate and the universal rear end plate, and the parallel current collecting plates are embedded in the grooves; a forward stacking single cell group is arranged between the parallel front end plate and the universal rear end plate; the pile distribution chamber is fixed on the parallel front end plate.

Further, the utility model also comprises a steel belt; the single cell group is fixed with the end plate through a steel belt.

Further, the stack distribution chambers are located in the same direction on the tandem front end plates.

Because the parallel-connection design scheme of the electric pile adopts two groups of fuel cell groups with the same stacking direction, the two groups of fuel cell groups with the same stacking direction are connected in parallel through the front and rear parallel current collecting plates to form positive and negative poles respectively, and a load is interposed between the positive and negative poles to form a closed loop. The parallel scheme can realize doubling of the output current of the electric pile under the condition of not changing the design of the bipolar plate and the membrane electrode of the fuel cell, and can be applied to the application scene of high current and low voltage. Meanwhile, the scheme reduces the original 4 current collecting plates to 2, the universal rear end plate is universal to the serial scheme, and the universal rear end plate is also universal to a copper plate and a copper plate fixing seat which do not need to be connected between the electric piles, so that the application scene of the electric piles is expanded while the structure of the electric piles is simplified, the connection impedance between the electric piles is reduced, the practicability of the electric piles is improved, and the development cost of the electric piles is reduced.

In the two technical schemes, the main structural parts of the electric pile are the same, such as the general rear end plate, the electric pile distribution cavity and the steel belt, and the structures of the rest parts are basically similar, such as: the serial front end plate, the parallel front end plate and the parallel current collecting plate are basically consistent in fixing hole position, mounting position and mounting mode, and when the serial and parallel scheme process switching is carried out, the rear end plates of the serial and parallel scheme are all universal rear end plates, so that when the serial scheme is switched to the parallel scheme, the serial current collecting plate is only required to be replaced by the parallel current collecting plate, the serial front end plate is replaced by the parallel front end plate, and the stacking directions of the single battery packs 4 and 5 are switched to be stacked in the same direction; on the contrary, if the parallel scheme is switched to the series scheme, only the parallel current collecting plate is replaced by the series current collecting plate, the parallel front end plate is replaced by the series front end plate, and the stacking directions of the single cell groups 4 and 5 are switched to be stacked in opposite directions, so that the production can be performed without adjusting production line equipment, and the pile structure with the series-parallel flexible switching can be realized. The utility model aims at the problem that the active area of the current-stage electric pile is fixed and the current output by the electric pile cannot be changed under the rated current density of the electric pile. In the series scheme, high-voltage low-current output of the cell stack can be achieved, and in the parallel scheme, high-current low-voltage output of the cell stack can be achieved.

Compared with the prior art, the utility model has the advantages that:

1. The multi-stack integrated design principle omits two end plates, a current collecting plate, a switching copper plate and a fixing seat thereof, reduces the complexity of the multi-stack structure and simplifies the pile structure.

2. At present, a high-power fuel cell system mostly adopts a double-stack serial scheme, and the scheme has a complicated structure in the system arrangement process. If the design scheme of the utility model is adopted, the copper plate transferring and fixing device can be omitted.

2. The double-stack synchronous stacking is realized, the production speed is improved, and simultaneously, the multi-stack synchronous assembly is beneficial to improving the multi-stack size consistency.

3. The pile structure of the utility model improves the integration level and the compactness of the pile.

4. The pile structure can realize the improvement of single-module pile power.

5. The pile structure can effectively reduce the production cost and the production efficiency of the pile.

6. The two schemes of series connection and parallel connection realize the universality of the universal rear end plate and the electric pile distribution cavity, and simultaneously, the core parts of the electric pile such as the membrane electrode, the bipolar plate and the like of the electric pile are universal, so that the applicable scenes of the electric pile are enriched, the cost of the electric pile is reduced, and the production efficiency of the electric pile is improved.

7. The pile structure of the utility model can produce the pile with high voltage current and low voltage and high current according to the requirements, and realize the flexible design of the pile.

8. The novel multi-fuel cell stack integrated structure enables the positive electrode and the negative electrode of the fuel cell current collecting plate to be positioned at the same side of the stack, and greatly reduces the volume and the connection length of the positive and negative electrode copper plates. In addition, the rear current collecting plate is made into an integrated design, so that the sectional area of two stacks of electronic flow is increased, more than two points are integrated, and ohmic impedance of multi-stack connection can be effectively reduced.

Drawings

FIG. 1 is a schematic diagram of a fuel cell stack series configuration of the present utility model;

FIG. 2 is a diagram of a universal rear end plate, collector plate insulator plug, and tandem rear collector plate fit in a tandem arrangement;

FIG. 3 is a diagram of the front end plate mated with the front header plate in a tandem arrangement;

FIG. 4 is a schematic diagram of a parallel structure of a fuel cell stack;

FIG. 5 is a diagram of the mating of a parallel front end plate with a parallel current collector in a parallel arrangement;

Fig. 6 is a diagram of the universal rear end plate mated with the parallel header in a parallel arrangement.

The individual components in the figure are as follows: the universal rear end plate 1, the serial front end plate 2, the current collecting plate insulating plug 3, the forward stacking single cell group 4, the reverse stacking single cell group 5, the serial front current collecting plate 6, the steel belt 7, the electric pile distribution cavity 8, the serial rear current collecting plate 9, the parallel current collecting plate 10 and the parallel front end plate 11.

Detailed Description

In the following description, technical solutions are set forth in connection with specific illustrations in order to provide a full understanding of the present application. This application may be carried out in a number of ways other than those herein set forth, and similar embodiments would be apparent to those of ordinary skill in the art without undue burden from the present disclosure.

Example 1

In this embodiment, a galvanic pile series design scheme is adopted, as shown in fig. 1,2 and 3. The pile series design scheme consists of a general rear end plate 1, a series front end plate 2, a current collecting plate insulating plug 3, a forward stacking single cell group 4, a reverse stacking single cell group 5, a series front current collecting plate 6, a steel belt 7, a pile distribution cavity 8 and a series rear current collecting plate 9.

First, in the present embodiment, the front end plate and the rear end plate of the multi-fuel cell stack are each integrated into one end plate. As shown in fig. 2, the serial rear current collecting plates 9 are embedded in corresponding grooves of the universal rear end plate 1; the current collecting plate insulating plugs 3 are fixed on corresponding end plate notches by bolts, so that the problem of insulation of the electric pile caused by foreign matters falling onto the current collecting plates 9 after series connection from the notches is avoided (the notch is formed, so that the 1-general rear end plate is compatible with a multi-pile series connection scheme and a multi-pile parallel connection scheme simultaneously). As shown in fig. 3, two tandem front current collecting plates 6 are embedded into corresponding grooves of the tandem front end plates 2. As shown in fig. 1, the forward stacked cell group 4 and the reverse stacked cell group 5 are stacked and mounted between the common rear end plate 1 and the tandem front end plate 2, then the cell groups are fixed to the end plates by steel strips 7, and finally the gas distribution chambers 8 are bolted to the tandem front end plate 2, and the directions of the forward stacked cell group 4 and the reverse stacked cell group 5 are opposite, so that the directions of the gas distribution chambers 8 are opposite when they are fixed to the tandem front end plate 2.

In this embodiment, two back current collecting plates are integrated into one back current collecting plate connected in series, so that the current cross-sectional area of the two stacks can be increased, the ohmic impedance of the connection of the stacks can be reduced, and meanwhile, the switching copper plate for multi-stack series connection is omitted. In the technical scheme, the same side of the distribution cavity of the electric pile is designed, and the operation principle of the fuel cell is utilized to reversely stack the cathode plates and the anode plates of the multiple piles, so that the distribution cavities of the multiple piles are distributed on the same side.

Example 2

In this embodiment, the galvanic pile adopts a parallel design scheme, as shown in fig. 4, 5 and 6. The parallel pile design scheme mainly comprises a general rear end plate 1, a single cell group 4, a steel belt 7, a pile distribution cavity 8, two parallel current collecting plates 10 and a parallel front end plate 11. In the present embodiment, the front end plate and the rear end plate of the multi-fuel cell stack are respectively integrated into one end plate in the same serial scheme as in embodiment 1, except that the parallel current collecting plates 10 of the parallel scheme in the present embodiment are integrated into the same piece in front and back, that is, the common rear end plate 1 and the parallel front end plate 11 are embedded into the parallel current collecting plates 10 in the grooves. As shown in fig. 5, the parallel collector plates 10 are embedded in corresponding grooves of the parallel front end plates 11. As shown in fig. 6, the parallel collector plates 10 are embedded in corresponding grooves of the universal rear end plate 1. As shown in fig. 4, two sets of single cell stacks 4 are mounted between the common rear end plate 1 and the parallel front end plate 11, then the single cell stacks and the end plates are fixed by the steel belt 7, and finally the gas distribution chambers 8 are fixed to the serial front end plate 2 by bolts, and since the two sets of single cell stacks 4 are in the same direction, the gas distribution chambers 8 are in the same direction fixed to the parallel front end plate 11.

In this embodiment, the front and rear current collecting plates are integrated into the front and rear parallel current collecting plates 10, which simplifies the structure of the stack, and increases the cross-sectional area of the current flow of the multi-stack connection, reduces the ohmic impedance of the multi-stack connection, and omits the switching copper plate for multi-stack series connection.

Example 3

In this embodiment, the pile adopts a design scheme capable of implementing serial-parallel flexible switching, as shown in fig. 1, fig. 2, fig. 3, fig. 4 and fig. 5. The serial scheme and the parallel scheme are all universal parts in the universal rear end plate 1, the steel belt 7 and the electric pile distribution cavity 8, so that the serial-parallel scheme is switched only by switching the stacking directions of the current collecting plates, the front end plate and the single cell groups 4 and 5 corresponding to the serial-parallel scheme. To realize the series switching to parallel scheme, the series front end plate 2 needs to be replaced by the parallel front end plate 11, the series current collecting plate 6 needs to be replaced by the parallel current collecting plate 10, and meanwhile, the single cell groups are stacked in the same direction to realize the switching. To achieve a parallel to series switching scheme, the parallel front end plate 11 needs to be replaced by a series front end plate, the parallel current collecting plate 10 needs to be replaced by a series current collecting plate 6, and meanwhile, the single cell groups 4 and 5 are reversely stacked to achieve switching. Because the serial and parallel scheme is to stack the single cell group on the universal rear end plate 1, the front end plate is covered after stacking, and then the single cell group is fastened by the steel belt 7, the assembly process is not required to be modified, and only the non-universal parts of the corresponding scheme are required to be replaced.

While embodiments of the present utility model have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the utility model, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the utility model.

Claims (8)

1. The integrated connection structure of the fuel cell stack is characterized by comprising a universal rear end plate (1), a serial front end plate (2), a stacked single cell group and a stack distribution cavity (8);

The connection mode between the stacked single cell groups is series connection; the stacked cell group includes a forward stacked cell group (4) and a reverse stacked cell group (5);

Grooves are formed in the universal rear end plate (1) and the serial front end plate (2); the serial connection rear current collecting plate (9) is embedded in a groove formed in the universal rear end plate (1), and the serial connection front current collecting plate (6) is embedded in a groove formed in the serial connection front end plate (2); the forward stacking single cell group (4) and the reverse stacking single cell group (5) are arranged between the universal rear end plate (1) and the serial front end plate (2), and the stacking directions of the forward stacking single cell group (4) and the reverse stacking single cell group (5) are opposite; the pile distribution cavity (8) is fixed on the front end plate (2) in series.

2. The fuel cell stack integrated connection structure according to claim 1, wherein the forward stacked cell group (4) and the reverse stacked cell group (5) are fixed with the common rear end plate (1) and the tandem front end plate (2) by steel strips (7).

3. The fuel cell stack integrated connection structure according to claim 1, further comprising a collector plate insulating plug (3); the current collecting plate insulating plug (3) is fixed on a notch on the universal rear end plate (1).

4. A fuel cell stack integrated connection according to claim 1, wherein the stack distribution chambers (8) are located in opposite directions on the tandem front end plate (2).

5. The integrated connection structure of a fuel cell stack according to claim 1, wherein the number of the front current collecting plates (6) in series is 2, and two front current collecting plates (6) in series are embedded into corresponding grooves of the front end plates (2) in series.

6. The integrated connection structure of the fuel cell stack is characterized in that the cell stack adopts a parallel connection mode, and the structure comprises a general rear end plate (1), a forward stacked single cell stack (4), a steel belt (7), a stack distribution cavity (8), a parallel current collecting plate (10) and a parallel front end plate (11);

Grooves for embedding the parallel current collecting plates (10) are formed in the parallel front end plate (11) and the universal rear end plate (1), and the parallel current collecting plates (10) are embedded in the grooves; a forward stacking single cell group (4) is arranged between the parallel front end plate (11) and the universal rear end plate (1); the pile distribution cavity (8) is fixed on a parallel front end plate (11).

7. The fuel cell stack integrated connection structure according to claim 6, further comprising a steel strip (7); the single cell group and the end plate are fixed through a steel belt (7).

8. A fuel cell stack integrated connection according to claim 6, wherein the stack distribution chambers (8) are located in the same direction on the tandem front end plate (2).