Fuel cell

Abstract

A fuel cell includes at least two stacked and adjacent single cells, wherein the cathode plate (1) of one single cell is stacked and adjacent to the anode plate (2) of an adjacent single cell. It is characterized in that the cathode plate (1) includes a cathode plate body (11), and a cathode flow channel ridge (12) protruding towards the anode plate (2) is arranged on the cathode plate body (11), and a cathode flow channel (121) is formed in the cathode flow channel ridge (12). The anode plate (2) includes an anode plate body (21), and an anode flow channel ridge (22) protruding towards the cathode plate (1) is arranged on the anode plate body (21), and an anode flow channel (221) is formed in the anode flow channel ridge (22). A cooling channel (3) is formed between the cathode plate (1) and the anode plate (2). The anode flow channel ridge (22) and the cathode flow channel ridge (12) are arranged crosswise, and the included angle range between the anode flow channel ridge (22) and the cathode flow channel ridge (12) is 60° to 120°.

Description

Technical Field

[0001] The present invention relates to the field of electrochemical cells, and more particularly to a fuel cell. Background Art

[0002] A fuel cell can react hydrogen with oxygen in the air to generate electricity, and the reaction product is water. Not limited by the Carnot cycle, the efficiency can reach more than 50%, so it is not only environmentally friendly but also energy-saving. A bipolar plate fuel cell includes a cathode plate and an anode plate. A cathode flow channel is formed on one side of the cathode plate, and an oxidizing gas (such as oxygen) is adapted to flow in the cathode flow channel. An anode flow channel is formed on one side of the anode plate, and a reducing gas (such as hydrogen) is adapted to flow in the anode flow channel. A cooling channel is formed between the cathode plate and the anode plate, and a coolant is adapted to flow in the cooling channel. The cathode plate and the anode plate are important components of the bipolar plate fuel cell, and play a role in supporting the fuel cell, providing reaction gases and cooling channels.

[0003] Fuel cells have a wide range of applications in fields such as automobiles and airplanes. This field has relatively high requirements for the power density of fuel cells. In the technical route of improving the power density of fuel cells, reducing the thickness of the cathode plate and the anode plate can achieve very significant effects.

[0004] For the convenience of processing, the cathode flow channel, the anode flow channel, and the cooling channel of existing fuel cells are all in a parallel relationship (such as German Patent DE102013208450A1). Therefore, in the fluid distribution transition region at both ends of the flow channel, three fluids need to be distributed, and the complexity of the fluid distribution transition region is relatively concentrated. In a traditional bipolar plate structure with a thickness of about 1 mm, this concentration of complexity is not a big problem. However, when the thickness is reduced to less than 0.6 mm, the fluid distribution transition region will become a bottleneck for increasing the scale of a single cell. The single cell current of existing fuel cells with relatively thin bipolar plates (such as a thickness of only 0.6 mm) is difficult to reach 600 A, so it is not easy to meet the application requirements of ultra-high power in fields such as automobiles and airplanes. Summary of the Invention

[0005] In view of this, the present invention aims to provide a fuel cell to reduce the complexity of the fluid distribution transition region.

[0006] To achieve the above object, the technical solution of the present invention is realized as follows:

[0007] A fuel cell includes at least two stacked and adjacent single cells, where the cathode plate of one single cell is stacked and adjacent to the anode plate of an adjacent single cell. The cathode plate includes a cathode plate body, and a cathode flow channel ridge protruding towards the anode plate is provided on the cathode plate body. A cathode flow channel is formed within the cathode flow channel ridge. The anode plate includes an anode plate body, and an anode flow channel ridge protruding towards the cathode plate is provided on the anode plate body. An anode flow channel is formed within the anode flow channel ridge. A cooling channel is formed between the cathode plate and the anode plate. The anode flow channel ridge and the cathode flow channel ridge are arranged crosswise, and the included angle between the anode flow channel ridge and the cathode flow channel ridge ranges from 60° to 120°.

[0008] According to some embodiments of the present invention, the anode flow channel ridge and the cathode flow channel ridge are arranged perpendicularly.

[0009] According to some embodiments of the present invention, a ridge is provided at the intersection of the anode flow channel ridge and the cathode flow channel ridge. The anode flow channel ridge is fitted with the ridge in an embedded manner. The ridge is located on the flow path of the cathode flow channel and is recessed towards the inside of the cathode flow channel. The flow channel depth of the cathode flow channel at the ridge is less than the flow channel depth of the cathode flow channel outside the ridge.

[0010] Further, the flow channel depth of the cathode flow channel at the ridge is 0.2 mm, and the flow channel depth of the cathode flow channel outside the ridge is 0.4 mm.

[0011] According to some embodiments of the present invention, there are multiple anode flow channel ridges, and the multiple anode flow channel ridges are arranged in parallel at intervals; there are multiple cathode flow channel ridges, and the multiple cathode flow channel ridges are arranged in parallel at intervals.

[0012] According to some embodiments of the present invention, the anode flow channel ridge has multiple sub-flow channel ridges. Sub-flow channels communicating with the anode flow channel are formed within the sub-flow channel ridges. The sub-flow channel ridges are parallel to the cathode flow channel ridges.

[0013] Further, the sub-flow channel ridges of adjacent two anode flow channel ridges are arranged alternately.

[0014] Further, the sub-flow channel ridges are located between adjacent two cathode flow channel ridges.

[0015] Further, the sub-flow channel ridges are spaced apart from the cathode plate body to communicate with the cooling channel; the cathode flow channel ridges are in contact with the anode plate body.

[0016] Further, the cathode plate is an oxygen-side plate, and the anode plate is a hydrogen-side plate.

[0017] Compared with the prior art, the fuel cell of the present invention has the following advantages:

[0018] According to the fuel cell of the present invention, the anode flow channel ridges and the cathode flow channel ridges are arranged crosswise, which is beneficial to reducing the complexity of the fluid distribution transition region, and further beneficial to reducing the thicknesses of the cathode plate and the anode plate, so as to achieve the improvement of the power density of the fuel cell and the maximum discharge current of the fuel cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0020] Figure 1 is a schematic diagram after the cathode plate and the anode plate are stacked;

[0021] Figure 2 is a schematic diagram of one side of the anode plate facing the cooling channel;

[0022] Figure 3 is a schematic diagram of one side of the cathode plate facing the MEA (membrane electrode assembly);

[0023] Figure 4 is Figure 1 an enlarged view at C;

[0024] Figure 5 is Figure 4 a sectional view taken along A-A;

[0025] Figure 6 is Figure 4 a sectional view taken along A'-A';

[0026] Figure 7 is Figure 1 a sectional view taken along B-B;

[0027] Figure 8 is Figure 6 an enlarged view at D;

[0028] Figure 9 is a schematic layout diagram of the cathode flow channel, the anode flow channel, and the cooling channel.

[0029] DESCRIPTION OF THE REFERENCE NUMERALS:

[0030] Cathode plate 1, cathode plate body 11, cathode flow channel ridge 12, cathode flow channel 121, ridge 122, anode plate 2, anode plate body 21, anode flow channel ridge 22, anode flow channel 221, auxiliary flow channel ridge 23, auxiliary flow channel 231, cooling channel 3, hydrogen inlet manifold chamber 20, hydrogen outlet manifold chamber 30, oxygen inlet manifold chamber 40, oxygen outlet manifold chamber 50, reaction zone 60, transition zone 70. DETAILED DESCRIPTION OF THE INVENTION

[0031] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other.

[0032] The following will refer to Figures 1-9 and describe the present invention in detail in conjunction with embodiments.

[0033] Refer to Figures 1-3 , Figure 7 As shown, the fuel cell according to an embodiment of the present invention includes at least two stack - adjacent single cells, wherein the cathode plate 1 of one single cell is stack - adjacent to the anode plate 2 of an adjacent single cell.

[0034] The cathode plate 1 includes a cathode plate body 11, on which a cathode flow channel ridge 12 protruding towards the anode plate 2 is provided. A cathode flow channel 121 is formed within the cathode flow channel ridge 12, and an oxidizing gas flows in the cathode flow channel 121. The oxidizing gas can be air, and the oxygen in the air participates in the electrochemical reaction within the fuel cell.

[0035] The anode plate 2 includes an anode plate body 21, on which an anode flow channel ridge 22 protruding towards the cathode plate 1 is provided. An anode flow channel 221 is formed within the anode flow channel ridge 22, and a reducing gas flows in the anode flow channel 221. The reducing gas can be hydrogen.

[0036] A cooling channel 3 is formed between the cathode plate 1 and the anode plate 2. Specifically, the cooling channel 3 is formed at the non - fitting part between the cathode plate 1 and the anode plate 2, and a coolant or a cooling agent flows in the cooling channel 3.

[0037] Fluid distribution transition zones need to be provided at both ends of the cathode flow channel 121, the anode flow channel 221, and the cooling channel 3 to achieve the distribution of the oxidizing gas, the reducing gas, and the coolant.

[0038] The anode flow channel ridge 22 and the cathode flow channel ridge 12 are arranged cross -wise, and the included angle range between the anode flow channel ridge 22 and the cathode flow channel ridge 12 is 60° to 120°, so as to separate and arrange the fluid distribution transition zones of the cathode flow channel 121 and the anode flow channel 221 (i.e., Figure 1 the hydrogen inlet manifold chamber 20, the hydrogen outlet manifold chamber 30, the oxygen inlet manifold chamber 40, and the oxygen outlet manifold chamber 50 in

[0039] According to the fuel cell of the present invention, the anode flow channel ridge 22 and the cathode flow channel ridge 12 are arranged crosswise, which is beneficial to reducing the complexity of the fluid distribution transition region, and further beneficial to reducing the thicknesses of the cathode plate 1 and the anode plate 2, so as to improve the power density of the fuel cell and increase the maximum discharge current of the fuel cell.

[0040] Referring to Figure 1 As shown, the anode flow channel ridge 22 and the cathode flow channel ridge 12 are arranged perpendicularly to maximize the separation distance of the fluid distribution transition regions of the cathode flow channel 121 and the anode flow channel 221, which is beneficial to further reducing the thicknesses of the cathode plate 1 and the anode plate 2, and further beneficial to improving the power density of the fuel cell and increasing the maximum discharge current of the fuel cell.

[0041] Referring to Figure 4 、 Figure 6 、 Figure 8 As shown, a ridge 122 is provided at the intersection of the anode flow channel ridge 22 and the cathode flow channel ridge 12. The anode flow channel ridge 22 and the ridge 122 are fitted in an embedded manner. The ridge 122 is located on the flow path of the cathode flow channel 121, and the ridge 122 is recessed into the interior of the cathode flow channel 121. The flow channel depth e of the cathode flow channel 121 at the ridge 122 is smaller than the flow channel depth f of the cathode flow channel 121 outside the ridge 122.

[0042] Specifically, on the cathode flow channel ridge 12, a plurality of ridges 122 recessed into the interior of the cathode flow channel 121 are provided along the flowing direction of the oxidizing gas. The positions and numbers of the ridges 122 correspond to the positions and numbers of the intersections of the anode flow channel ridge 22 and the cathode flow channel ridge 12, so as to realize the engagement of the ridges 122 on the cathode flow channel ridge 12 and the anode flow channel ridge 22, which is beneficial to the assembly of the cathode plate 1 and the anode plate 2 and ensures the correct relative positions of the cathode plate 1 and the anode plate 2.

[0043] The ridge 122 will slightly increase the gas resistance of the cathode flow channel 121. However, the number of flow channels of the anode plate 2 is small and the depth is shallow. That is to say, the number of ridges 122 on each cathode flow channel 121 is small, and the increase in gas resistance is not significant. At the same time, some turbulence is generated when the oxidizing gas flows through the ridge 122, which is beneficial to promoting mass transfer and exchange.

[0044] Further, referring to Figure 8As shown, in some embodiments of the present invention, the channel depth e of the cathode flow channel 121 at the ridge 122 is 0.2 mm, the channel depth f of the cathode flow channel 121 outside the ridge 122 is 0.4 mm, the thickness g of the cathode plate 1 before forming is 0.1 mm, the thickness h of the anode plate 2 before forming is 0.1 mm, and the depth i of the anode flow channel 221 is 0.2 mm. That is to say, the total thickness after the cathode plate 1 and the anode plate 2 are assembled is 0.6 mm, which is beneficial to improving the power density of the fuel cell. The single-cell current can reach 10,000 A, which can meet the application requirements of ultra-high power.

[0045] Referring to Figure 2 As shown, there are multiple anode flow channel ridges 22, and the multiple anode flow channel ridges 22 are arranged in parallel at intervals, which is beneficial to ensuring that hydrogen is as evenly distributed as possible in the anode flow channel 221 and discharging the anode products in a timely manner.

[0046] Referring to Figure 3 As shown, there are multiple cathode flow channel ridges 12, and the multiple cathode flow channel ridges 12 are arranged in parallel at intervals. This is beneficial to ensuring that air is as evenly distributed as possible in the cathode flow channel 121 and discharging the cathode products in a timely manner.

[0047] Referring to Figure 2 As shown, the anode flow channel ridge 22 has multiple secondary flow channel ridges 23. A secondary flow channel 231 communicating with the anode flow channel 221 is formed in the secondary flow channel ridge 23, and the secondary flow channel ridge 23 is parallel to the cathode flow channel ridge 12.

[0048] Furthermore, the secondary flow channel ridges 23 of two adjacent anode flow channel ridges 22 are arranged alternately.

[0049] Furthermore, the secondary flow channel ridge 23 is located between two adjacent cathode flow channel ridges 12.

[0050] That is to say, the anode flow field is an interdigitated flow field formed by the anode flow channel 221 and the secondary flow channel 231 superimposed on a secondary fractal interdigitated flow field. Specifically, as Figure 2 shown, multiple anode flow channels 221 form an interdigitated flow field, and the secondary flow channels 231 of multiple anode flow channels 221 form a secondary fractal interdigitated flow field. And referring to Figure 1 shown, the secondary flow channel ridge 23 is located between two adjacent cathode flow channel ridges 12, which is beneficial to ensuring the sufficient supply of oxygen at high current density and further beneficial to ensuring the performance of the fuel cell.

[0051] In some embodiments of the present invention, referring to Figure 5 shown, the secondary flow channel ridge 23 is spaced apart from the cathode plate body 11 to communicate with the cooling channel 3. Referring to Figure 6 shown, the cathode flow channel ridge 12 is in contact with the anode plate body 21. Referring to Figure 7As shown, a cooling channel 3 is formed between the cathode plate body 11 and the anode plate body 21 between two adjacent cathode flow channel ridges 12, and a coolant flows in the cooling channel 3.

[0052] In some embodiments of the present invention, the cathode plate 1 is an oxygen-side plate, and the anode plate 2 is a hydrogen-side plate.

[0053] Referring to Figure 1 、 Figures 3-4 As shown, one end of the cathode plate 1 is an oxygen inlet manifold chamber 40, and the other end is an oxygen outlet manifold chamber 50. Oxygen enters the cathode flow channel 121 from the oxygen inlet manifold chamber 40, and the excess oxygen flows out of the cathode flow channel 121 and enters the oxygen outlet manifold chamber 50. Referring to Figures 1-2 、 Figure 4 As shown, one end of the anode plate 2 is a hydrogen inlet manifold chamber 20, and the other end is a hydrogen outlet manifold chamber 30. Hydrogen enters the cathode flow channel 121 from the hydrogen inlet manifold chamber 20, and the excess hydrogen flows out of the anode flow channel 221 and enters the hydrogen outlet manifold chamber 30.

[0054] It can be seen from Figure 1 that the hydrogen inlet manifold chamber 20 and the hydrogen outlet manifold chamber 30 are arranged at both ends of the anode plate 2, the oxygen inlet manifold chamber 40 and the oxygen outlet manifold chamber 50 are arranged at both ends of the cathode plate 1, and the included angle range between the connection line of the hydrogen inlet manifold chamber 20 and the hydrogen outlet manifold chamber 30 and the connection line of the oxygen inlet manifold chamber 40 and the oxygen outlet manifold chamber 50 is 60° to 120°, preferably 90°, that is, the connection line of the hydrogen inlet manifold chamber 20 and the hydrogen outlet manifold chamber 30 is perpendicular to the connection line of the oxygen inlet manifold chamber 40 and the oxygen outlet manifold chamber 50. The hydrogen inlet manifold chamber 20, the hydrogen outlet manifold chamber 30, the oxygen inlet manifold chamber 40, and the oxygen outlet manifold chamber 50 are separately arranged, which is beneficial to reducing the complexity of the fluid distribution transition zone (i.e., each manifold chamber), and further beneficial to eliminating the bottleneck caused by the inability to arrange the fluid distribution transition zone when the scale of the single cell of the ultra-thin cathode plate 1 and the ultra-thin anode plate 2 is enlarged, so as to improve the power density of the fuel cell.

[0055] Combined with Figure 9 As shown, the oxygen in the cathode flow channel 121 reacts with the hydrogen in the anode flow channel 221 in the reaction zone 60, the coolant flows in the cooling channel 3, and there is also a transition zone 70 in the fuel cell to buffer the oxygen in the cathode flow channel 121 and the hydrogen in the anode flow channel 221, which is beneficial to the full reaction of hydrogen and oxygen.

[0056] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A fuel cell, comprising at least two stack - adjacent single cells, wherein the cathode plate of one single cell is stack - adjacent to the anode plate of an adjacent single cell. Characterized in that, The cathode plate comprises a cathode plate body, on which a cathode flow channel ridge protruding towards the anode plate is provided, and a cathode flow channel is formed within the cathode flow channel ridge; the anode plate comprises an anode plate body, on which an anode flow channel ridge protruding towards the cathode plate is provided, and an anode flow channel is formed within the anode flow channel ridge; a cooling channel is formed between the cathode plate and the anode plate; the anode flow channel ridge and the cathode flow channel ridge are arranged cross -wise, and the included angle range between the anode flow channel ridge and the cathode flow channel ridge is 60° to 120°. A ridge is provided at the intersection of the anode flow channel ridge and the cathode flow channel ridge, the anode flow channel ridge is embedded and fitted with the ridge, the ridge is located on the flow path of the cathode flow channel and is recessed into the interior of the cathode flow channel, and the flow channel depth of the cathode flow channel at the ridge is less than the flow channel depth of the cathode flow channel outside the ridge.

2. The fuel cell according to claim 1, Characterized in that, The anode flow channel ridge and the cathode flow channel ridge are arranged perpendicularly.

3. The fuel cell according to claim 1, Characterized in that, The flow channel depth of the cathode flow channel at the ridge is 0.2 mm, and the flow channel depth of the cathode flow channel outside the ridge is 0.4 mm.

4. The fuel cell according to claim 1, Characterized in that, There are multiple anode flow channel ridges, and the multiple anode flow channel ridges are arranged in parallel at intervals; there are multiple cathode flow channel ridges, and the multiple cathode flow channel ridges are arranged in parallel at intervals.

5. The fuel cell according to claim 1, Characterized in that, The anode flow channel ridge has multiple sub - flow channel ridges, and sub - flow channels communicating with the anode flow channel are formed within the sub - flow channel ridges, and the sub - flow channel ridges are parallel to the cathode flow channel ridges.

6. The fuel cell according to claim 5, Characterized in that, The sub - flow channel ridges of adjacent two anode flow channel ridges are arranged alternately.

7. The fuel cell according to claim 5, Characterized in that, The sub - flow channel ridge is located between two adjacent cathode flow channel ridges.

8. The fuel cell according to claim 5, Characterized in that, The sub - flow channel ridge is spaced apart from the cathode plate body to communicate with the cooling channel; the cathode flow channel ridge is in contact with the anode plate body.

9. The fuel cell according to any one of claims 1 - 8, Characterized in that, The cathode plate is an oxygen - side plate, and the anode plate is a hydrogen - side plate.

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