High-pressure-resistant membrane electrode assembly and proton exchange membrane electrolytic cell

Abstract

The utility model relates to the technical field of hydrogen production equipment, in particular to a high-pressure-resistant membrane electrode assembly and a proton exchange membrane electrolytic bath. The high-voltage-resistant membrane electrode assembly comprises a membrane electrode, two plastic electrode frames and two diffusion layers. The membrane electrode is arranged between the two plastic electrode frames and is plastically packaged through hot pressing, the projection size of the membrane electrode is larger than that of frame inner holes of the plastic electrode frames, the shape of the diffusion layers is the same as that of the frame inner holes of the plastic electrode frames, and the two diffusion layers are embedded in the frame inner holes of the two plastic electrode frames respectively and tightly attached to the membrane electrode. The filler is arranged at the gap between the outer periphery of the diffusion layer and the inner periphery of the frame inner hole, so that the membrane electrode is completely wrapped by the plastic electrode frame, the diffusion layer and the filler, the pressure of a high-pressure environment is completely dispersed by the wrapping piece, and hydrogen and oxygen blow-by caused by the fact that the membrane electrode is punctured by high pressure is avoided. A thinner proton exchange membrane can be adopted, so that the electrochemical efficiency of the proton exchange membrane is improved, and the cost of the proton exchange membrane electrolytic cell is reduced.

Description

Technical Field

[0001] This utility model relates to the field of hydrogen production equipment technology, and in particular to a high-pressure resistant membrane electrode assembly and a proton exchange membrane electrolyzer. Background Technology

[0002] Hydrogen, as a pollution-free and environmentally friendly renewable energy source, has enormous potential to alleviate the current energy crisis and environmental problems. Proton exchange membrane electrolysis of water to produce hydrogen offers advantages such as zero emissions and high hydrogen purity, and is considered one of the most promising methods for large-scale industrial hydrogen production in the future. Currently, a large amount of wind and solar power generation is being wasted; this technology can convert electrical energy into high-energy-density hydrogen for storage, improving the overall efficiency of renewable energy and the power grid.

[0003] As a complex system involving multiple coupled fields of electrochemistry, thermodynamics, fluid dynamics, and structure, the sealing performance of a proton exchange membrane electrolyzer is paramount for safe operation. Because membrane electrodes are not easily resistant to high pressure, under high-pressure hydrogen conditions, thinner proton exchange membranes with better electrochemical performance are more prone to rupture at the interface between the electrode frame and the diffusion layer, posing a risk of hydrogen and oxygen mixing and potential safety hazards. Due to this limitation, most commercially available proton exchange membranes on the market are thicker and have better mechanical properties, such as DuPont N117 and N115, which to some extent reduces the electrochemical performance of the electrolyzer. Utility Model Content

[0004] The purpose of this invention is to provide a high-pressure resistant membrane electrode assembly and a proton exchange membrane electrolyzer, which improves the high-pressure resistance of the membrane electrode at the junction of the electrode frame and the diffusion layer, enabling the proton exchange membrane electrolyzer to use a proton exchange membrane with better electrochemical performance but thinner thickness.

[0005] To achieve the above objectives, in a first aspect, this utility model provides a high-pressure resistant membrane electrode assembly, including a membrane electrode, two plastic electrode frames and two diffusion layers, wherein the plastic electrode frames are respectively provided with an inlet, an outlet, a hydrogen outlet and multiple fixing holes.

[0006] The membrane electrode includes a proton exchange membrane and a catalyst layer coated on both sides of the proton exchange membrane. The membrane electrode is set between two plastic electrode frames and sealed by hot pressing. The projected size of the membrane electrode is larger than the projected size of the inner hole of the plastic electrode frame. The inner hole, water inlet, water outlet, hydrogen outlet and fixing hole of the two plastic electrode frames are aligned respectively.

[0007] The shape of the diffusion layer is the same as the shape of the inner hole of the plastic electrode frame. The two diffusion layers are respectively embedded in the inner holes of the two plastic electrode frames and are closely attached to the film electrode.

[0008] Filler is placed in the gap between the outer periphery of the diffusion layer and the inner periphery of the frame hole.

[0009] Optionally, the inner hole of the plastic electrode frame is rectangular, with inner rounded corners at the turning points of the inner hole, and outer rounded corners matching the inner rounded corners at the edges of the diffusion layer.

[0010] Optionally, the range of inner and outer fillets is 0.5mm to 5mm.

[0011] Optionally, the filler is a polymer material.

[0012] Optionally, the filler is any one of perfluorosulfonic acid polytetrafluoroethylene copolymer, polyethylene, polyethylene naphthalate, polytetrafluoroethylene, polyphenylene sulfide and polypropylene.

[0013] Secondly, this utility model also provides a proton exchange membrane electrolyzer, comprising a positive end plate, an anode insulating plate, an anode current collector, a first anode sealing frame, a first high-voltage resistant membrane electrode assembly, a first cathode sealing frame, a bipolar plate, a second anode sealing frame, a second high-voltage resistant membrane electrode assembly, a second cathode sealing frame, a cathode current collector, a cathode insulating plate, and a cathode end plate stacked sequentially. The first high-voltage resistant membrane electrode assembly and the second high-voltage resistant membrane electrode assembly both adopt any one of the high-voltage resistant membrane electrode assemblies in the first aspect, and the first high-voltage resistant membrane electrode assembly and the second high-voltage resistant membrane electrode assembly have the same structure. The two diffusion layers of the first high-voltage resistant membrane electrode assembly are respectively embedded in the inner holes of the first anode sealing frame and the first cathode sealing frame, and the two diffusion layers of the second high-voltage resistant membrane electrode assembly are respectively embedded in the inner holes of the second anode sealing frame and the second cathode sealing frame.

[0014] The anode end plate, anode insulating plate, anode current collector, first anode sealing frame, first cathode sealing frame, bipolar plate, second anode sealing frame, and second cathode sealing frame are each provided with a water inlet and a water outlet, which are respectively aligned with the water inlet and water outlet on the high-pressure resistant membrane electrode assembly to form a water inlet channel and a water outlet channel.

[0015] The first anode sealing frame, the first cathode sealing frame, the bipolar plate, the second anode sealing frame, the second cathode sealing frame, the cathode current collector, the cathode insulating plate, and the cathode end plate are each provided with a hydrogen outlet, which is aligned with the hydrogen outlet on the high-voltage membrane electrode assembly to form a hydrogen outlet channel.

[0016] The anode end plate, anode insulating plate, anode current collector, first anode sealing frame, first cathode sealing frame, bipolar plate, second anode sealing frame, second cathode sealing frame, cathode current collector, cathode insulating plate and cathode end plate are each provided with multiple fixing holes, and each fixing hole is aligned with a fixing hole on the high-voltage resistant membrane electrode assembly to form a fixing channel for the locking bolt to pass through.

[0017] A first water-oxygen flow field is provided on the side of the anode current collector facing the first anode sealing frame, and the flow channel of the first water-oxygen flow field is connected to the inlet and outlet of the anode current collector;

[0018] A first hydrogen flow field is provided on the side of the cathode current collector facing the second cathode sealing frame, and the flow channel of the first hydrogen flow field is connected to the hydrogen outlet on the cathode current collector.

[0019] A second hydrogen flow field is provided on the side of the bipolar plate facing the first cathode sealing frame. The flow channel of the second hydrogen flow field is connected to the hydrogen outlet on the bipolar plate. A second water-oxygen flow field is provided on the side of the bipolar plate facing the second anode sealing frame. The flow channel of the second water-oxygen flow field is connected to the water inlet and water outlet on the bipolar plate.

[0020] Optionally, the flow directions of the first water-oxygen flow field and the first hydrogen flow field are perpendicular;

[0021] The flow directions of the second water-oxygen flow field and the second hydrogen flow field are perpendicular.

[0022] Optionally, a sealing groove is provided around the outer side of the end of the anode insulating plate facing the water inlet and outlet.

[0023] A sealing groove is provided around the outer side of the water inlet and water outlet of the anode current collector facing the anode insulating plate, and a sealing groove is provided around the outer side of the first water-oxygen flow field and the connected water inlet and water outlet.

[0024] On the side of the first anode sealing frame facing the first high-pressure resistant membrane electrode assembly, sealing grooves are respectively provided for the inner hole of the frame, the water inlet, the water outlet and the hydrogen outlet surrounding the first anode sealing frame;

[0025] On the side of the first cathode sealing frame facing the first high-pressure resistant membrane electrode assembly, sealing grooves are respectively provided for the inner hole of the first cathode sealing frame, the water inlet, the water outlet and the hydrogen outlet.

[0026] A sealing groove is provided around the outer side of the inlet and outlet of the bipolar plate facing the first cathode sealing frame, and a sealing groove is provided around the outer side of the second hydrogen flow field and the connected hydrogen outlet. A sealing groove is provided around the outer side of the hydrogen outlet of the bipolar plate facing the second anode sealing frame, and a sealing groove is provided around the outer side of the second water-oxygen flow field and the connected inlet and outlet.

[0027] On the side of the second anode sealing frame facing the second high-pressure membrane electrode assembly, sealing grooves are respectively provided for the inner hole of the frame, the water inlet, the water outlet and the hydrogen outlet surrounding the second anode sealing frame;

[0028] On the side of the second cathode sealing frame facing the second high-pressure resistant membrane electrode assembly, sealing grooves are respectively provided for the inner hole of the second cathode sealing frame, the water inlet, the water outlet and the hydrogen outlet.

[0029] A sealing groove is provided on the outer side of the end of the hydrogen outlet on the cathode current collector facing the cathode insulating plate, and a sealing groove is provided on the outer side of the first hydrogen flow field and the connected hydrogen outlet.

[0030] A sealing groove is provided around the outer side of the end of the hydrogen outlet on the cathode end plate that faces the cathode insulating plate.

[0031] Each sealing groove is provided with a sealing ring. The width dimension of the sealing ring's cross-section is smaller than the width dimension of the sealing groove's cross-section, and the inner side of the sealing ring is in close contact with the inner wall of the sealing groove.

[0032] Optionally, the width dimension of the sealing ring cross-section is 50% to 80% of the width dimension of the sealing groove cross-section.

[0033] Optionally, the orthographic projections of the sealing grooves surrounding the inner hole of the first anode sealing frame and the first cathode sealing frame are interlocked.

[0034] The orthographic projections of the sealing grooves surrounding the inner holes of the second anode sealing frame and the second cathode sealing frame are interlocked.

[0035] The above-mentioned technical solution of this utility model has the following advantages:

[0036] This utility model provides a high-pressure resistant membrane electrode assembly comprising a membrane electrode, two plastic electrode frames, and two diffusion layers. The plastic electrode frames are respectively provided with an inlet, an outlet, a hydrogen outlet, and multiple fixing holes. The membrane electrode is disposed between the two plastic electrode frames and sealed by heat pressing. The projected size of the membrane electrode is larger than the projected size of the inner hole of the plastic electrode frame. The inner hole, inlet, outlet, hydrogen outlet, and fixing holes of the two plastic electrode frames are aligned. The shape of the diffusion layer is the same as the shape of the inner hole of the plastic electrode frame. The two diffusion layers are respectively embedded in the inner holes of the two plastic electrode frames and are tightly attached to the membrane electrode. A filler is placed in the gap between the outer periphery of the diffusion layer and the inner periphery of the inner hole, so that the membrane electrode is completely covered by the plastic electrode frame, diffusion layer, and filler. The pressure of the high-pressure environment is completely dispersed by the covering, preventing hydrogen and oxygen cross-contamination caused by high pressure puncturing the membrane electrode. With this structure, a thinner proton exchange membrane can be used, improving the electrochemical efficiency of the proton exchange membrane and helping to reduce the cost of the proton exchange membrane electrolyzer.

[0037] The proton exchange membrane electrolyzer provided by this utility model includes the above-mentioned high-voltage resistant membrane electrode assembly, which can be made thinner, thereby improving the electrochemical efficiency of the proton exchange membrane and reducing the cost of the proton exchange membrane electrolyzer.

[0038] This utility model provides a proton exchange membrane electrolyzer, in which a sealing groove is set on the outer periphery of an inlet, outlet, hydrogen outlet, inner hole of the frame, water-oxygen flow, and hydrogen flow field between two adjacent components, and a sealing ring is set in the sealing groove. The width dimension of the sealing ring in the cross-sectional direction is smaller than the width dimension of the sealing groove in the cross-sectional direction, and the inner side of the sealing ring is tightly attached to the inner sidewall of the sealing groove, so that gas can enter the sealing groove and squeeze the sealing ring to achieve compression sealing.

[0039] The present invention provides a proton exchange membrane electrolyzer in which the orthographic projections of the sealing grooves surrounding the inner holes of a pair of anode sealing frames and cathode sealing frames are spaced out. After the electrolyzer is assembled, multi-stage sealing is achieved, further improving the sealing effect. Attached Figure Description

[0040] The accompanying drawings are provided for illustrative purposes only, and the proportions and quantities of the components in the drawings may not be consistent with the actual product.

[0041] Figure 1 This is a three-dimensional structural schematic diagram of a high-voltage resistant membrane electrode assembly according to Embodiment 1 of this utility model;

[0042] Figure 2 yes Figure 1 Another structural schematic diagram of a medium- and high-voltage membrane electrode assembly;

[0043] Figure 3 yes Figure 2 Enlarged diagram of part A in the diagram;

[0044] Figure 4 yes Figure 3 Schematic diagram of the BB cross section in the middle;

[0045] Figure 5 yes Figure 4 Enlarged schematic diagram of part C in the diagram;

[0046] Figure 6 yes Figure 1 A schematic diagram of the disassembled structure of a medium- and high-voltage membrane electrode assembly;

[0047] Figure 7 This is a schematic diagram of the structure of a proton exchange membrane electrolyzer according to Embodiment 2 of this utility model;

[0048] Figure 8 yes Figure 7 Another structural diagram of a medium proton exchange membrane electrolyzer (fastening bolts are not shown);

[0049] Figure 9 yes Figure 7 Schematic diagram of the decomposition state structure of a medium proton exchange membrane electrolyzer;

[0050] Figure 10 This is a front view structural schematic diagram of an anode current collector according to Embodiment 2 of this utility model;

[0051] Figure 11 yes Figure 10 Rear view schematic diagram of the center anode current collector;

[0052] Figure 12 This is a front view structural diagram of a first anode sealing frame in Embodiment 2 of this utility model;

[0053] Figure 13 yes Figure 12 Schematic diagram of the DD cross section in the middle;

[0054] Figure 14 yes Figure 13 Enlarged schematic diagram of part E in the diagram;

[0055] Figure 15 This is a front view schematic diagram of a bipolar plate according to Embodiment 2 of this utility model;

[0056] Figure 16 yes Figure 15 Rear view of the bipolar plate structure;

[0057] Figure 17 This is a front view structural schematic diagram of a cathode current collector according to Embodiment 2 of this utility model.

[0058] In the picture:

[0059] 1: High-voltage resistant membrane electrode assembly;

[0060] 101: Membrane electrode;

[0061] 102: Plastic electrode frame;

[0062] 103: Diffusion layer;

[0063] 104: Water inlet;

[0064] 105: Water outlet;

[0065] 106: Hydrogen outlet;

[0066] 107: Fixing hole;

[0067] 108: Filler;

[0068] 2: Anode plate;

[0069] 3: Anode insulating board;

[0070] 4: Anode current collector;

[0071] 401: First water-oxygen flow field;

[0072] 5: First anode sealing frame;

[0073] 6: First cathode sealing frame;

[0074] 7: Bipolar plate;

[0075] 701: Second hydrogen flow field;

[0076] 702: Second water-oxygen flow field;

[0077] 8: Second anode sealing frame;

[0078] 9: Second cathode sealing frame;

[0079] 10: Cathode current collector;

[0080] 1001: First hydrogen gas flow field;

[0081] 11: Cathode insulating plate;

[0082] 12: Negative extreme plate;

[0083] 13: Sealing groove;

[0084] 14: Sealing ring. Detailed Implementation

[0085] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0086] It is worth noting that in this application, the inlet, outlet, hydrogen outlet, fixing hole, sealing groove, and sealing ring are all considered as separate components. Therefore, the same reference numerals are used on different components. Based on the description and illustrations in this application, the description is clear. Furthermore, the shapes of the sealing groove and sealing ring may differ on different components, but they are all annular. For example, the sealing groove outside a circular inlet is annular, while the one outside a square inner hole is square. The sealing ring has the same shape and size as the sealing groove it belongs to.

[0087] Example 1

[0088] like Figures 1-6As shown, the high-pressure resistant membrane electrode assembly 1 provided in this embodiment of the present invention includes a membrane electrode 101, two plastic electrode frames 102, and two diffusion layers 103. The plastic electrode frames 102 are respectively provided with an inlet 104, an outlet 105, a hydrogen outlet 106, and multiple fixing holes 107.

[0089] The membrane electrode 101 includes a proton exchange membrane and catalyst layers coated on both sides of the proton exchange membrane. It should be noted that coating the proton exchange membrane with catalyst layers on both sides to form a membrane electrode is existing technology and will not be described further here. See [link to relevant documentation] Figure 4 and Figure 5 As shown, the membrane electrode 101 is disposed between two plastic electrode frames 102 and sealed by heat pressing. The projected size of the membrane electrode 101 is larger than the projected size of the inner hole of the plastic electrode frame 102. The inner holes, inlet 104, outlet 105, hydrogen outlet 106, and fixing hole 107 of the two plastic electrode frames 102 are aligned. The shape of the diffusion layer 103 is the same as the shape of the inner hole of the plastic electrode frame 102. The two diffusion layers 103 are respectively embedded in the inner holes of the two plastic electrode frames 102 and are tightly attached to the membrane electrode 101.

[0090] See Figure 2 , Figure 3 and Figure 5 As shown, a filler 108 is placed in the gap between the outer periphery of the diffusion layer 103 and the inner periphery of the frame's inner hole, so that the membrane electrode 101 is completely covered by the plastic electrode frame 102, the diffusion layer 103, and the filler 108. The pressure of the high-pressure environment is completely dispersed by the covering, preventing hydrogen and oxygen cross-contamination caused by high pressure puncturing the membrane electrode. With this structure, a thinner proton exchange membrane can be used, improving the electrochemical efficiency of the proton exchange membrane and helping to reduce the cost of the proton exchange membrane electrolyzer.

[0091] In this embodiment, the filler 108 is obtained by fluid filling followed by solidification.

[0092] It should be noted that thermoforming is an existing technology and will not be elaborated upon here.

[0093] It should also be noted that, Figure 2 and Figure 3 The gap between the outer periphery of the diffusion layer 103 and the inner periphery of the inner hole of the frame is obtained by enlarging the schematic diagram. In actual applications, this gap may be due to factors such as different processing precision or different coefficients of thermal expansion and contraction of materials (which are usually difficult to avoid). Therefore, this gap is usually very small and is basically discontinuously distributed throughout the circumference.

[0094] In practical applications, the membrane electrode 101 is often punctured at corners. See one example. Figure 2 and Figure 6As shown, the inner hole of the plastic electrode frame 102 is rectangular, and the turning points of the inner hole are provided with inner rounded corners. The edges of the diffusion layer 103 are provided with outer rounded corners that match the inner rounded corners, which can disperse the stress on the membrane electrode under high pressure and further reduce the risk of the membrane electrode 101 being punctured by stress and pressure. Preferably, the range of the inner and outer rounded corners is 0.5mm to 5mm.

[0095] In this embodiment, preferably, the filler 108 is a polymer material. In some examples, the filler can be any one of perfluorosulfonic acid polytetrafluoroethylene copolymer, polyethylene, polyethylene naphthalate, polytetrafluoroethylene, polyphenylene sulfide, and polypropylene.

[0096] In this embodiment, the inlet 104, outlet 105, hydrogen outlet 106, and fixing hole 107 are all round holes.

[0097] In this embodiment, the diffusion layer 103 is made of titanium felt.

[0098] Example 2

[0099] like Figures 7-9 As shown, the proton exchange membrane electrolyzer provided in this embodiment includes, in sequence, an anode end plate 2, an anode insulating plate 3, an anode current collector 4, a first anode sealing frame 5, a first high-voltage membrane electrode assembly, a first cathode sealing frame 6, a bipolar plate 7, a second anode sealing frame 8, a second high-voltage membrane electrode assembly, a second cathode sealing frame 9, a cathode current collector 10, a cathode insulating plate 11, and a cathode end plate 12. Both the first and second high-voltage membrane electrode assemblies employ any one of the high-voltage membrane electrode assemblies 1 described in Embodiment 1, and the structures of the first and second high-voltage membrane electrode assemblies are identical; that is, only one membrane electrode structure is used in the same electrolyzer. The two diffusion layers 103 of the first high-voltage membrane electrode assembly 1 are respectively embedded in the inner holes of the first anode sealing frame 5 and the first cathode sealing frame 6, and the two diffusion layers 103 of the second high-voltage membrane electrode assembly 1 are respectively embedded in the inner holes of the second anode sealing frame 8 and the second cathode sealing frame 9.

[0100] See Figure 3 As shown, the anode end plate 2, anode insulating plate 3, anode current collector 4, first anode sealing frame 5, first cathode sealing frame 6, bipolar plate 7, second anode sealing frame 8, and second cathode sealing frame 9 are each provided with a water inlet 104 and a water outlet 105, which are respectively aligned with the water inlet 104 and water outlet 105 on the high-pressure resistant membrane electrode assembly 1 to form a water inlet channel and a water outlet channel.

[0101] The first anode sealing frame 5, the first cathode sealing frame 6, the bipolar plate 7, the second anode sealing frame 8, the second cathode sealing frame 9, the cathode current collector 10, the cathode insulating plate 11, and the cathode end plate 12 are each provided with a hydrogen outlet 106, which is aligned with the hydrogen outlet 106 on the high-voltage resistant membrane electrode assembly 1 to form a hydrogen outlet channel.

[0102] The anode end plate 2, anode insulating plate 3, anode current collector 4, first anode sealing frame 5, first cathode sealing frame 6, bipolar plate 7, second anode sealing frame 8, second cathode sealing frame 9, cathode current collector 10, cathode insulating plate 11, and cathode end plate 12 are each provided with multiple fixing holes 107. The number of fixing holes on each of the above components is the same as the number of fixing holes on a plastic electrode frame 102. Each fixing hole 107 is aligned with a fixing hole on the high-voltage resistant membrane electrode assembly 1 to form a fixing channel through which the locking bolt passes.

[0103] See Figures 9-11 As shown, the anode current collector 4 is provided with a first water-oxygen flow field 401 on the side facing the first anode sealing frame 5, and the flow channel of the first water-oxygen flow field 401 is connected to the water inlet 104 and the water outlet 105 on the anode current collector.

[0104] See Figure 9 and Figure 17 As shown, a first hydrogen flow field 1001 is provided on the side of the cathode current collector 10 facing the second cathode sealing frame 9, and the flow channel of the first hydrogen flow field 1001 is connected to the hydrogen outlet 106 on the cathode current collector 10.

[0105] See Figure 9 , Figure 15 and Figure 16 As shown, a second hydrogen flow field 701 is provided on the side of the bipolar plate 7 facing the first cathode sealing frame 6. The flow channel of the second hydrogen flow field 701 is connected to the hydrogen outlet 106 on the bipolar plate 7. A second water-oxygen flow field 702 is provided on the side of the bipolar plate 7 facing the second anode sealing frame 8. The flow channel of the second water-oxygen flow field 702 is connected to the water inlet 104 and the water outlet 105 on the bipolar plate 7.

[0106] In this embodiment, the flow directions of the first water-oxygen flow field 401 and the first hydrogen flow field 1001 are perpendicular. The flow directions of the second water-oxygen flow field 702 and the second hydrogen flow field 701 are also perpendicular, avoiding overlap between the water-oxygen flow field and the hydrogen flow field, which could lead to hydrogen-oxygen cross-contamination and internal leakage. It should be noted that the existing structures for the water-oxygen flow field and the hydrogen flow field can be used, and will not be elaborated further here.

[0107] In this embodiment, a sealing groove 13 is respectively provided around the outer side of the end of the anode insulating plate 3 facing the water inlet 104 and the water outlet 105 on the anode end plate 2.

[0108] A sealing groove 13 is provided around the outer side of the inlet 104 and outlet 105 of the anode current collector 4 facing the anode insulating plate 3, and a sealing groove 13 is provided around the outer side of the first water-oxygen flow field 401 and the connected inlet 104 and outlet 105.

[0109] See Figures 12-14 As shown, on the side of the first anode sealing frame 5 facing the first high-pressure resistant membrane electrode assembly 1, there are sealing grooves 13 surrounding the inner hole of the first anode sealing frame 5, the water inlet 104, the water outlet 105 and the hydrogen outlet 106.

[0110] Preferably, the water inlet, water outlet, and hydrogen outlet on the same component are staggered. For example, see the block diagram. Figure 12 As shown, they are set on the three sides respectively.

[0111] The structure of the first cathode sealing frame 6 is basically the same as that of the first anode sealing frame 5, therefore it can be referred to Figures 12-14 Understand the structure of the first cathode sealing frame 6. On the side of the first cathode sealing frame 6 facing the first high-voltage membrane electrode assembly 1, there are sealing grooves 13 surrounding the inner hole of the first cathode sealing frame 6, the water inlet 104, the water outlet 105 and the hydrogen outlet 106.

[0112] See Figure 15 and Figure 16 As shown, a sealing groove 13 is respectively provided around the outer side of the water inlet 104 and water outlet 105 on the bipolar plate 7 facing the first cathode sealing frame 6. A sealing groove 13 is also provided around the outer side of the second hydrogen flow field 701 and the connected hydrogen outlet 106. A sealing groove 13 is also provided around the outer side of the hydrogen outlet 106 on the bipolar plate 7 facing the second anode sealing frame 8. A sealing groove 13 is also provided around the outer side of the second water-oxygen flow field 702 and the connected water inlet 104 and water outlet 105.

[0113] The structure of the second anode sealing frame 8 is basically the same as that of the first anode sealing frame 5, therefore it can be referred to Figures 12-14 Understand the structure of the second anode sealing frame 8. On the side of the second anode sealing frame 8 facing the second high-pressure membrane electrode assembly 1, there are sealing grooves 13 surrounding the inner hole of the second anode sealing frame 8, the water inlet 104, the water outlet 105 and the hydrogen outlet 106.

[0114] The structure of the second cathode sealing frame 9 is basically the same as that of the first anode sealing frame 5, therefore it can be referred to Figures 12-14 Understand the structure of the second cathode sealing frame 9. On the side of the second cathode sealing frame 9 facing the second high-voltage membrane electrode assembly 1, there are sealing grooves 13 surrounding the inner hole of the second cathode sealing frame 9, the water inlet 104, the water outlet 105 and the hydrogen outlet 106.

[0115] See Figure 17 As shown, a sealing groove 13 is provided on the outer side of the hydrogen outlet 106 on the cathode current collector 10 facing the cathode insulating plate 11, and a sealing groove 13 is provided on the outer side of the first hydrogen flow field 1001 and the connected hydrogen outlet 106.

[0116] See Figure 9 As shown, a sealing groove 13 is provided around the outer side of the hydrogen outlet 106 on the cathode end plate 12 facing the cathode insulating plate 11.

[0117] refer to Figure 13 and Figure 14 As shown, each sealing groove 13 is provided with a sealing ring 14. The width dimension of the sealing ring 14's cross-section is smaller than the width dimension of the sealing groove's cross-section, and the inner side of the sealing ring 14 is in close contact with the inner wall of the sealing groove 13, so that there is a certain gap between the outer wall of the sealing ring 14 and the outer wall of the sealing groove 13. The thickness of the sealing ring 13 (taking a circular sealing ring as an example, the thickness refers to the axial dimension of the sealing ring) is slightly higher than that of the sealing groove 13. During assembly, the sealing ring 14 is squeezed in the axial direction to provide a planar seal (this is the prior art). On this basis, the width dimension of the sealing ring 14's cross-section (again taking a circular sealing ring as an example, the width dimension of the sealing ring 14's cross-section is the radial direction of the sealing ring) is smaller than the width dimension of the sealing groove's cross-section. During use, gas can enter the sealing groove 13 and squeeze the sealing ring 14 in the radial direction to achieve a squeeze seal, further improving the sealing effect and preventing side leakage of hydrogen and oxygen. Preferably, the width dimension of the sealing ring 14 is 50% to 80% of the width dimension of the sealing groove 13.

[0118] In one example, the orthographic projections of the sealing grooves 13 surrounding the inner holes of the first anode sealing frame 5 and the first cathode sealing frame 6 are interlocked. That is, the orthographic projections of the sealing grooves 13 on the outer side of the inner hole of the first anode sealing frame 5 and the sealing grooves 13 on the outer side of the inner hole of the first cathode sealing frame 6 are misaligned. After the electrolytic cell is assembled, multi-level sealing is achieved, further improving the sealing effect.

[0119] The orthographic projections of the sealing grooves 13 surrounding the inner holes of the second anode sealing frame 8 and the second cathode sealing frame 9 are spaced out, achieving multi-stage sealing after the electrolytic cell is assembled, thus further improving the sealing effect.

[0120] In another embodiment, a proton exchange membrane electrolyzer has only one high-voltage resistant membrane electrode assembly. Specifically, the electrolyzer consists of an anode end plate, an anode insulating plate, an anode current collector, an anode sealing frame, a high-voltage resistant membrane electrode assembly, a cathode sealing frame, a cathode current collector, a cathode insulating plate, and a cathode end plate stacked sequentially.

[0121] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that not every embodiment contains only one independent technical solution. In the absence of any conflict between the solutions, the various technical features mentioned in each embodiment can be combined in any way to form other implementation methods that can be understood by those skilled in the art.

[0122] Furthermore, without departing from the scope of this utility model, modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions of some of the technical features, shall not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A high-voltage resistant membrane electrode assembly, characterized in that: It includes a membrane electrode, two plastic electrode frames and two diffusion layers. The plastic electrode frames are respectively provided with an inlet, an outlet, a hydrogen outlet and multiple fixing holes. The membrane electrode includes a proton exchange membrane and a catalyst layer coated on both sides of the proton exchange membrane. The membrane electrode is disposed between two plastic electrode frames and sealed by hot pressing. The projected size of the membrane electrode is larger than the projected size of the inner hole of the plastic electrode frame. The inner hole, water inlet, water outlet, hydrogen outlet and fixing hole of the two plastic electrode frames are aligned respectively. The shape of the diffusion layer is the same as the shape of the inner hole of the plastic electrode frame. The two diffusion layers are respectively embedded in the inner holes of the two plastic electrode frames and are close to the membrane electrode. A filler is provided in the gap between the outer periphery of the diffusion layer and the inner periphery of the frame hole.

2. The high-voltage resistant membrane electrode assembly according to claim 1, characterized in that: The inner hole of the plastic electrode frame is rectangular, and the turning points of the inner hole are provided with inner rounded corners. The edges of the diffusion layer are provided with outer rounded corners that match the inner rounded corners.

3. The high-voltage resistant membrane electrode assembly according to claim 2, characterized in that: The range of the inner and outer fillets is 0.5mm to 5mm.

4. The high-voltage resistant membrane electrode assembly according to claim 1, characterized in that: The filler is a polymer material.

5. The high-voltage resistant membrane electrode assembly according to claim 4, characterized in that: The filler is any one of perfluorosulfonic acid polytetrafluoroethylene copolymer, polyethylene, polyethylene naphthalate, polytetrafluoroethylene, polyphenylene sulfide, and polypropylene.

6. A proton exchange membrane electrolyzer, characterized in that: The device comprises, in sequence, a positive electrode plate, an anode insulating plate, an anode current collector, a first anode sealing frame, a first high-voltage resistant membrane electrode assembly, a first cathode sealing frame, a bipolar plate, a second anode sealing frame, a second high-voltage resistant membrane electrode assembly, a second cathode sealing frame, a cathode current collector, a cathode insulating plate, and a cathode electrode plate. Both the first and second high-voltage resistant membrane electrode assemblies employ the high-voltage resistant membrane electrode assembly as described in any one of claims 1 to 5, and the first and second high-voltage resistant membrane electrode assemblies have the same structure. The two diffusion layers of the first high-voltage resistant membrane electrode assembly are respectively embedded within the inner holes of the first anode sealing frame and the first cathode sealing frame, and the two diffusion layers of the second high-voltage resistant membrane electrode assembly are respectively embedded within the inner holes of the second anode sealing frame and the second cathode sealing frame. The anode end plate, anode insulating plate, anode current collector, first anode sealing frame, first cathode sealing frame, bipolar plate, second anode sealing frame, and second cathode sealing frame are each provided with a water inlet and a water outlet, which are respectively aligned with the water inlet and water outlet on the high-pressure resistant membrane electrode assembly to form a water inlet channel and a water outlet channel. The first anode sealing frame, the first cathode sealing frame, the bipolar plate, the second anode sealing frame, the second cathode sealing frame, the cathode current collector, the cathode insulating plate, and the cathode end plate are each provided with a hydrogen outlet, and are respectively aligned with the hydrogen outlet on the high-voltage resistant membrane electrode assembly to form a hydrogen outlet channel; The anode end plate, anode insulating plate, anode current collector, first anode sealing frame, first cathode sealing frame, bipolar plate, second anode sealing frame, second cathode sealing frame, cathode current collector, cathode insulating plate, and cathode end plate are each provided with multiple fixing holes, and each fixing hole is aligned with a fixing hole on the high-voltage resistant membrane electrode assembly to form a fixing channel for the locking bolt to pass through. The anode current collector is provided with a first water-oxygen flow field on the side facing the first anode sealing frame, and the flow channel of the first water-oxygen flow field is connected to the water inlet and the water outlet on the anode current collector; The cathode current collector is provided with a first hydrogen flow field on the side facing the second cathode sealing frame, and the flow channel of the first hydrogen flow field is connected to the hydrogen outlet on the cathode current collector. A second hydrogen flow field is provided on the side of the bipolar plate facing the first cathode sealing frame. The flow channel of the second hydrogen flow field is connected to the hydrogen outlet on the bipolar plate. A second water-oxygen flow field is provided on the side of the bipolar plate facing the second anode sealing frame. The flow channel of the second water-oxygen flow field is connected to the water inlet and water outlet on the bipolar plate.

7. The proton exchange membrane electrolyzer according to claim 6, characterized in that: The flow directions of the first water-oxygen flow field and the first hydrogen flow field are perpendicular; The flow directions of the second water-oxygen flow field and the second hydrogen flow field are perpendicular.

8. The proton exchange membrane electrolyzer according to claim 6, characterized in that: A sealing groove is respectively provided around the outer side of the end of the anode insulating plate facing the water inlet and outlet on the anode end plate; A sealing groove is provided around the outer side of the water inlet and water outlet on the anode current collector facing the anode insulating plate, and a sealing groove is provided around the outer side of the first water-oxygen flow field and the connected water inlet and water outlet. On the side of the first anode sealing frame facing the first high-pressure resistant membrane electrode assembly, sealing grooves are respectively provided for the inner hole of the frame, the water inlet, the water outlet and the hydrogen outlet surrounding the first anode sealing frame; On the side of the first cathode sealing frame facing the first high-pressure resistant membrane electrode assembly, sealing grooves are respectively provided for the inner hole of the first cathode sealing frame, the water inlet, the water outlet and the hydrogen outlet. A sealing groove is provided around the outer side of the water inlet and water outlet on the bipolar plate at the end facing the first cathode sealing frame, and a sealing groove is provided around the outer side of the second hydrogen flow field and the connected hydrogen outlet. A sealing groove is provided around the outer side of the hydrogen outlet on the bipolar plate at the end facing the second anode sealing frame, and a sealing groove is provided around the outer side of the second water-oxygen flow field and the connected water inlet and water outlet. On the side of the second anode sealing frame facing the second high-pressure resistant membrane electrode assembly, sealing grooves are respectively provided for the inner hole of the frame, the water inlet, the water outlet and the hydrogen outlet surrounding the second anode sealing frame; On the side of the second cathode sealing frame facing the second high-pressure resistant membrane electrode assembly, sealing grooves are respectively provided for the inner hole of the second cathode sealing frame, the water inlet, the water outlet and the hydrogen outlet. A sealing groove is provided on the outer side of the end of the hydrogen outlet on the cathode current collector facing the cathode insulating plate, and a sealing groove is provided on the outer side of the first hydrogen flow field and the connected hydrogen outlet. A sealing groove is provided around the outer side of the end of the cathode insulating plate where the hydrogen outlet faces the cathode insulating plate. Each of the sealing grooves is provided with a sealing ring, the width dimension of the sealing ring in the cross-sectional direction is smaller than the width dimension of the sealing groove in the cross-sectional direction, and the inner side of the sealing ring is in close contact with the inner sidewall of the sealing groove.

9. The proton exchange membrane electrolyzer according to claim 8, characterized in that: The width dimension of the sealing ring cross-section is 50% to 80% of the width dimension of the sealing groove cross-section.

10. The proton exchange membrane electrolyzer according to claim 8, characterized in that: The orthographic projections of the sealing grooves surrounding the inner hole of the first anode sealing frame and the first cathode sealing frame are interlocked. The orthographic projections of the sealing grooves surrounding the inner hole of the second anode sealing frame and the second cathode sealing frame are interlocked.

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