A fuel cell composite end plate and stack packaging structure

Abstract

The present invention relates to a fuel cell composite end plate and stack packaging structure, wherein the end plate comprises an aluminum alloy outer plate (1) and an insulating inner plate (2); the outer side of the aluminum alloy outer plate (1) is provided with a manifold mounting fixing hole, and the inner side is connected to the insulating inner plate (2); the insulating inner plate (2) is provided with a core support surface (21) and a fluid channel (22); the aluminum alloy outer plate (1) and the insulating inner plate (2) are integrally formed by injection molding, and a glue pouring groove is reserved between the aluminum alloy outer plate (1) and the insulating inner plate (2). Compared with the prior art, the present invention has the advantages of high integration, good sealing and insulation performance, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a composite end plate and stack packaging structure for a fuel cell. Background Art

[0002] Fuel cell vehicles, as a new energy vehicle, offer the advantages of cleanliness and environmental protection, and will become a hot topic in automotive research in the future. Fuel cell stacks are devices that convert the chemical energy in fuel into electrical energy. Fuel cell stacks do not produce harmful substances during the electrochemical reaction and are currently one of the main directions of new energy vehicle development internationally.

[0003] As one of the important components of the fuel cell stack, the fuel cell end plate needs to be installed to connect the insulating plate, bear the packaging force of the internal components of the fuel cell stack, tighten the fuel cell stack, and provide gas distribution channels, and meet IP68 protection requirements. Currently, most end plates and insulating plates on the fuel cell market are assembled as two separate parts. IP protection is achieved by adding an O-ring between the insulating plate and the end plate installation interface. The insulating plate is usually a thin-walled plastic flat plate. Due to the characteristics of the plastic itself and the influence of processing, the thin plate is extremely prone to warping and deformation, which has a great impact on the reliability of installation and IP sealing. Summary of the Invention

[0004] The object of the present invention is to provide a composite end plate and stack packaging structure for a fuel cell.

[0005] The objectives of the present invention can be achieved through the following technical solution: a fuel cell composite end plate comprising an aluminum alloy outer plate and an insulating inner plate; the outer side of the aluminum alloy outer plate is provided with a manifold mounting hole and is connected to the inner side of the insulating inner plate; the insulating inner plate is provided with a core support surface and a fluid channel; the aluminum alloy outer plate and the insulating inner plate are integrally formed by injection molding, and a glue pouring groove is reserved between the aluminum alloy outer plate and the insulating inner plate. The glue pouring groove is provided at the junction of the aluminum alloy outer plate and the insulating inner plate.

[0006] Preferably, a glue pouring line is provided in the glue pouring groove. The present invention adopts the form of glue pouring to ensure the IP68 sealing requirement. Preferably, silicone rubber is poured into the glue pouring groove to form a glue pouring line.

[0007] Preferably, a sealing ring is provided on the inner side of the aluminum alloy outer plate.

[0008] Further preferably, the sealing ring is arranged on the outside of the insulating inner plate. When the end plate is used to encapsulate the shell, the sealing ring can play a sealing effect.

[0009] Preferably, a composite structure is provided on the aluminum alloy outer plate.

[0010] Preferably, the aluminum alloy outer plate includes an abutting portion in contact with the insulating inner plate and a mounting portion for mounting and fixing.

[0011] Preferably, an insulating inner plate injection molding structure (such as a composite structure) and a flow channel structure are reserved on the aluminum alloy outer plate.

[0012] Preferably, the thickness of the aluminum alloy outer plate is 20 to 30 mm. The aluminum alloy outer plate and the insulating inner plate need to withstand the packaging force of the fuel cell core.

[0013] Preferably, the insulating inner plate is made of PPS engineering plastic with an insulation property greater than 11GΩ@1000V. The insulating inner plate must meet insulation requirements.

[0014] Preferably, the aluminum alloy outer plate and the insulating inner plate are integrally formed by embedded injection molding. Specifically, the following steps are included:

[0015] (1) Aluminum alloy outer plate die-casting;

[0016] (2) Finishing of aluminum alloy outer panels;

[0017] (3) Surface treatment of aluminum alloy outer panels;

[0018] (4) Pre-injection treatment of aluminum alloy outer panels;

[0019] (5) Injection molding an insulating inner plate onto the aluminum alloy outer plate.

[0020] A fuel cell stack packaging structure uses the above-mentioned composite end plate.

[0021] Preferably, the composite end plate is assembled on the shell (fuel cell stack package PACK) by bolts.

[0022] Further preferably, the shell is a box structure with one end open, and a composite end plate is assembled at the opening.

[0023] More preferably, a core is provided in the shell, and the core abuts against the core support surface.

[0024] At present, a fuel cell stack is generally composed of dozens to hundreds of fuel cells. When several fuel cells are assembled into a fuel cell stack, pressure must be applied to each cell through the end plate and fastening bolts to ensure good contact between the sections. At the same time, it is necessary to match the PACK to meet certain protection requirements to prevent foreign matter from contacting the stack and causing membrane electrode contamination / insulation problems. The existing technology requires the design of a dedicated sealing groove, the use of standard / special sealing rings and corresponding assembly structures to ensure the sealing and protection requirements of the PACK inside and outside, and requires additional sealing structures and assembly locking structures. The present invention integrates the insulating inner plate and the end plate into one part through embedded injection molding, and coats the plastic in the metal end plate matrix through injection molding. A notch is left at the interface between the plastic and the metal, and the IP68 protection of the composite end plate is met by filling glue in the notch. No additional sealing structure and assembly locking structure are required, and the integration is higher.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] 1. The present invention has high integration and reduces the number of parts in the end plate structure;

[0027] 2. Compared to the method of separating the aluminum alloy outer plate and the insulating inner plate and then connecting them with bolts and sealing them with O-rings, the insulating inner plate and the flow channel are integrally formed in the present invention, which can reduce the number of sealing strips;

[0028] 3. The insulating inner plate of the present invention is integrally formed with the aluminum alloy outer plate, and the sealing performance is increased from IP67 to IP68, which greatly improves the sealing and insulation performance;

[0029] 4. The modular injection molding product of the present invention has high efficiency, good consistency and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a cross-sectional view of the end plate of the present invention;

[0031] Figure 2 It is an outer side view of the end plate of the present invention;

[0032] Figure 3 This is a detailed view of the end plate of the present invention;

[0033] Figure 4 This is a diagram of the battery stack packaging structure of the present invention;

[0034] In the figure: 1-aluminum alloy outer plate, 11-abutment portion, 12-mounting portion, 2-insulating inner plate, 21-core supporting surface, 22-fluid channel, 3-glue pouring groove, 4-sealing ring, 5-composite structure, 6-shell, 7-core, a-composite end plate. DETAILED DESCRIPTION

[0035] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments are implemented based on the technical solution of the present invention, and provide detailed implementation methods and specific operating processes, but the protection scope of the present invention is not limited to the following embodiments.

[0036] Example 1

[0037] A composite end plate for a proton exchange membrane fuel cell stack, such as Figures 1 to 3 As shown, it is a composite end plate, which consists of an aluminum alloy outer plate 1 and an insulating inner plate 2. The insulating inner plate 2 is an insulating plate, and has a core support surface 21 and a fluid channel 22 formed by injection molding. The fluid inlet and outlet of the fluid channel 22 are connected to the corresponding interfaces of the core; the aluminum alloy outer plate 1 is an aluminum alloy end plate, which is composited with the insulating inner plate 2 to support the core. The edge can be installed with the shell, and the manifold installation fixing holes are arranged on the outside, as shown. Figures 1-2 As shown in the composite structure 5, the outer insulating plate is flush with the edge of the aluminum alloy end plate, serving as the reference plane for manifold installation and forming an insulating barrier (the insulating inner plate 2 wraps around the aluminum alloy outer plate 1, forming the insulating barrier). A glue pouring groove 3 is reserved between the insulating inner plate 2 and the aluminum alloy outer plate 1. After the composite end plate is injection-molded, glue is poured into the groove to form a glue pouring line, meeting IP68 protection requirements.

[0038] The end plate of this embodiment is tested according to the enclosure protection grade (IP code) of GB_T 4208-2017, and the protection performance meets the requirement of no water ingress at 1m@24h underwater.

[0039] Example 2

[0040] A composite end plate for a proton exchange membrane fuel cell stack is provided with an undercut composite structure 5 on an aluminum alloy outer plate 1, which can tightly combine the aluminum alloy outer plate 1 and the insulating inner plate 2. The rest is the same as in Example 1.

[0041] Example 3

[0042] A composite end plate for a proton exchange membrane fuel cell stack. An aluminum alloy outer plate 1 includes an abutment portion 11 for contacting an insulating inner plate 2 and a mounting portion 12 for mounting and fixing. Mounting portion 12 is provided with a sealing ring 4 and bolt holes. The remaining components are the same as those in Example 2.

[0043] Example 4

[0044] A fuel cell stack packaging structure, such as Figure 4 As shown, it includes the composite end plate a of Example 3 and a shell 6, a core 7 is arranged in the shell 6, the composite end plate a is one side of the shell 6, and is locked with the shell 6 by bolt assembly, and a sealing ring 4 is used to perform IP68 sealing.

[0045] The above description of the embodiments is intended to facilitate understanding and use of the invention by those skilled in the art. It will be apparent that those skilled in the art can readily make various modifications to these embodiments and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, the present invention is not limited to the above-described embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention, without departing from the scope of the present invention, should be within the scope of protection of the present invention.

Claims

1. A composite end plate for a fuel cell, characterized in that: It comprises an aluminum alloy outer plate (1) and an insulating inner plate (2); the outer side of the aluminum alloy outer plate (1) is provided with a manifold mounting fixing hole, and the inner side is connected to the insulating inner plate (2); the insulating inner plate (2) is provided with a core support surface (21) and a fluid channel (22); the aluminum alloy outer plate (1) and the insulating inner plate (2) are integrally formed by injection molding, and a glue pouring groove (3) is reserved between the aluminum alloy outer plate (1) and the insulating inner plate (2); A glue pouring line is provided in the glue pouring tank (3); A sealing ring (4) is provided on the inner side of the aluminum alloy outer plate (1); The sealing ring (4) is arranged on the outside of the insulating inner plate (2); An undercut composite structure (5) is provided on the aluminum alloy outer plate (1).

2. The fuel cell composite end plate according to claim 1, characterized in that: The aluminum alloy outer plate (1) comprises an abutting portion (11) in contact with the insulating inner plate (2) and a mounting portion (12) for mounting and fixing.

3. A fuel cell stack packaging structure, characterized in that: The composite end plate (a) according to any one of claims 1 to 2 is used.

4. The fuel cell stack packaging structure according to claim 3, characterized in that: The composite end plate (a) is assembled on the shell (6) by means of bolts.

5. The fuel cell stack packaging structure according to claim 4, characterized in that: The shell (6) is a box structure with one end open, and a composite end plate (a) is assembled at the opening.

6. The fuel cell stack packaging structure according to claim 5, characterized in that: A core (7) is arranged in the shell (6), and the core (7) abuts against the core support surface (21).

Images