A method for estimating slippage of fuel cell stack plates

Abstract

The present invention discloses a method for estimating the slippage of a fuel cell stack plate, comprising the following steps: establishing a fuel cell stack model; taking the plate closest to one end plate of the stack as the first plate, and taking the plate closest to the other end plate, that is, the last plate, as the second plate; N slice, definition N is the total number of plates; the length of the plate side parallel to the direction of gravity in the working condition is b , and the length of the side perpendicular to it is a , the thickness of a single plate is c , the mass of a single plate is m ; Calculate the n The present invention can accurately calculate the slip amount of each plate in a fuel cell stack when the specifications of different plates are known, thus providing a basis for the assembly design of the fuel cell stack.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cell stack assembly design, and in particular to a method for estimating the slippage of a fuel cell stack plate. Background Art

[0002] Under the background of energy constraints and environmental pollution, fuel cells have been gradually applied to industries, housing, transportation and other fields due to their many advantages such as high power generation efficiency and low environmental pollution, and have broad application prospects. A hydrogen fuel cell is a reaction device that converts the chemical energy of hydrogen and oxygen into electrical energy efficiently and pollution-free. It is mainly composed of an anode plate, a cathode plate and an electrolyte diaphragm. Due to the limited output current of a single cell, in practical applications, they must be stacked and then clamped on the end plate with fasteners. As fuel cells are increasingly tending to be high-pressure, resulting in a larger volume and longer span of the stack, under the action of their own gravity, relative slip will occur between the plates, and the overall phenomenon of bending downward will be shown. This further aggravates the uneven distribution of plate pressure, and even leads to the consequence of hydrogen leakage, reducing the service life and efficiency of the fuel cell. At present, there is no quantitative study on the slip of the plate under the action of gravity, and it is impossible to provide a quantitative basis for designers to estimate the slip of the plate. Summary of the invention

[0003] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0004] In view of the above and / or existing problems in estimating the slippage of the stack plates, the present invention is proposed.

[0005] Therefore, the problem to be solved by the present invention is that the prior art cannot quantitatively estimate the slippage of the stack plates, and the present invention can accurately and quantitatively estimate the slippage of the stack plates.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for estimating the slippage of a fuel cell stack plate, comprising the following steps:

[0007] Establish a fuel cell stack model;

[0008] The plate closest to one end plate of the stack is the first plate, the plate closest to the other end plate, i.e. the last plate, is the Nth plate, and N is defined as the total number of plates;

[0009] The length of the side parallel to the force direction of the plate in the working condition is b, the length of the side perpendicular to it is a, the thickness of the single plate is c, and the mass of the single plate is m;

[0010] Calculate the slip of the nth plate.

[0011] As a preferred solution of the method for estimating the slippage of the fuel cell stack plate of the present invention, the slippage y of the nth plate is calculated as follows:

[0012]

[0013] Among them, E eff is the equivalent Young's modulus, with the opposite direction of gravity as the positive direction.

[0014] The beneficial effect of the present invention is that the present invention can accurately calculate the slip amount of each electrode plate in a fuel cell stack when the specifications of different electrodes are known, thereby providing a basis for the assembly design of the fuel cell stack. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0016] Figure 1 It is the force diagram of the fuel cell stack model in the present invention.

[0017] Figure 2 This is a simulation result diagram of the plate slip amount when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=100, f=0.76, and F=20kN of the present invention.

[0018] Figure 3 This is a scatter diagram and a fitting curve diagram of the plate slip amount when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=100, f=0.76, and F=20kN of the present invention.

[0019] Figure 4 This is an error scatter diagram of the estimated slip amount relative to the simulation result when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=100, f=0.76, and F=20kN of the present invention.

[0020] Figure 5 This is a simulation result diagram of the plate slip amount when a=300mm, b=136mm, c=2mm, m=0.1547kg, N=100, f=0.76, and F=20kN of the present invention.

[0021] Figure 6 It is a scatter diagram and a fitting curve diagram of the plate slip amount when a=300mm, b=136mm, c=2mm, m=0.1547kg, N=100, f=0.76, and F=20kN of the present invention.

[0022] Figure 7 This is the error scatter diagram of the estimated slip amount relative to the simulation result when a=300mm, b=136mm, c=2mm, m=0.1547kg, N=100, f=0.76, and F=20kN of the present invention.

[0023] Figure 8 This is a simulation result diagram of the plate slip amount when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=100, f=0.66, and F=20kN of the present invention.

[0024] Fig. 9 This is a scatter diagram and a fitting curve diagram of the plate slip amount when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=100, f=0.66, and F=20kN of the present invention.

[0025] Fig.10 This is an error scatter diagram of the estimated slip amount relative to the simulation result when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=100, f=0.66, and F=20kN of the present invention.

[0026] Fig.11 This is a simulation result diagram of the plate slip amount when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=100, f=0.76, and F=30kN of the present invention.

[0027] Fig.12 This is a scatter diagram and a fitting curve diagram of the plate slip amount when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=100, f=0.76, and F=30kN of the present invention.

[0028] Fig.13 This is an error scatter diagram of the estimated slip amount relative to the simulation result when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=100, f=0.76, and F=30kN of the present invention.

[0029] Fig.14 This is a simulation result diagram of the plate slip amount when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=200, f=0.76, and F=20kN of the present invention.

[0030] Fig.15 This is a scatter diagram and a fitting curve diagram of the plate slip amount when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=200, f=0.76, and F=20kN of the present invention.

[0031] Fig.16 This is an error scatter diagram of the estimated slip amount relative to the simulation result when a=426mm, b=180mm, c=2mm, m=0.26876kg, N=200, f=0.76, and F=20kN of the present invention. DETAILED DESCRIPTION

[0032] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0033] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0034] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0035] Example 1

[0036] This is the first embodiment of the present invention, which provides a method for estimating the slippage of a fuel cell stack plate, comprising the following steps:

[0037] (S1) establishing a fuel cell stack model;

[0038] (S2) The electrode plate closest to one end plate of the stack is the first electrode plate, and the electrode plate closest to the other end plate, i.e., the last electrode plate, is the Nth electrode plate, and N is defined as the total number of electrode plates;

[0039] (S3) The length of the side of the plate parallel to the direction of gravity in the working condition is b, the length of the side perpendicular to it is a, the thickness of the single plate is c, and the mass of the single plate is m;

[0040] (S4) Calculate the slip amount of the n-th electrode plate. The slip amount y of the n-th electrode plate is calculated by the formula:

[0041]

[0042] Among them, E eff is the equivalent Young's modulus, with the opposite direction of gravity as the positive direction.

[0043] The calculation formula of the present invention is simple, the residual is small, and the calculation amount is small. It is suitable for estimating the slippage of each plate under gravity in various fuel cells. It can accurately calculate the slippage of each plate in the fuel cell stack when the specifications of different plates are known, providing a basis for the assembly design of the fuel cell stack.

[0044] Example 2

[0045] Reference Figure 1 to Figure 4 , which is the second embodiment of the present invention, and this embodiment uses scientific verification means to verify that the method in this application can be used to estimate the amount of slip under gravity.

[0046] This embodiment uses finite element simulation analysis software to simulate the fuel cell stack, and compares the data obtained after the simulation with the data calculated using the present invention.

[0047] The graphite bipolar plate has a length of 426 mm, a width of 180 mm, a thickness of 2 mm, and a mass of 0.26876 kg.

[0048] The total number of plates is N = 100, the friction coefficient between the plates is f = 0.76, the clamping force of the battery stack is F = 20000N, E eff =35.42303MPa.

[0049] The calculation steps are as follows:

[0050] (1) According to the slip calculation formula:

[0051]

[0052] (2) Calculate the slip of the 20th plate:

[0053]

[0054] The simulation results are as follows Figure 2 , the slip amount is -0.00225641mm, and the fitting curve is as follows Figure 3 , and the error with the calculated result is within 5%. Figure 4 As shown;

[0055] (3) Calculate the slip of the 70th plate:

[0056]

[0057] The simulation results are as follows Figure 2 , the slip amount is -0.00307786mm, and the fitting curve is as follows Figure 3, and the error of the calculated result is within 1%, such as Figure 4 shown.

[0058] Example 3

[0059] Reference Figure 1 , Figure 5 to Figure 7 , which is the third embodiment of the present invention, this embodiment uses finite element simulation analysis software to simulate the fuel cell stack, and compares the data obtained after the simulation with the data calculated using the present invention, that is, compares the calculation results by means of scientific argumentation to verify the real effect of this method.

[0060] The graphite bipolar plate has a length of 300 mm, a width of 136 mm, a thickness of 2 mm, and a mass of 0.1547 kg.

[0061] The total number of plates is N = 100, the friction coefficient between the plates is f = 0.76, the clamping force of the battery stack is F = 20000N, E eff =88.61239MPa.

[0062] The calculation steps are as follows:

[0063] (1) According to the slip calculation formula:

[0064]

[0065] (2) Calculate the slip of the 45th plate:

[0066]

[0067] The simulation results are as follows Figure 5 , the slip amount is -0.0027453mm, and the fitting curve is as follows Figure 6 , and the error with the calculated result is within 2% Figure 7 As shown;

[0068] (3) Calculate the slip of the 82nd plate:

[0069]

[0070] The simulation results are as follows Figure 5 , the slip amount is -0.00162604mm, and the fitting curve is as follows Figure 6 , and the error with the calculated result is within 5%. Figure 7 shown.

[0071] Example 4

[0072] Reference Figure 1 , Figure 8 to Figure 10, which is the third embodiment of the present invention, this embodiment uses finite element simulation analysis software to simulate the fuel cell stack, and compares the data obtained after the simulation with the data calculated using the present invention, that is, compares the calculation results by means of scientific argumentation to verify the real effect of this method.

[0073] The graphite bipolar plate has a length of 426 mm, a width of 180 mm, a thickness of 2 mm, and a mass of 0.26876 kg.

[0074] The total number of plates is N = 100, the friction coefficient between the plates is f = 0.66, the clamping force of the battery stack is F = 20000N, E eff =30.97165Mpa.

[0075] The calculation steps are as follows:

[0076] (1) According to the slip calculation formula:

[0077]

[0078] (2) Calculate the slip of the 15th plate:

[0079]

[0080] The simulation results are as follows Figure 8 , the slip amount is -0.0020314mm, and the fitting curve is as follows Fig. 9 , and the error with the calculated result is within 10%. Fig.10 As shown;

[0081] (3) Calculate the slip of the 80th plate:

[0082]

[0083] The simulation results are as follows Figure 8 , the slip amount is -0.0026818mm, and the fitting curve is as follows Fig. 9 , and the error with the calculated result is within 5%. Fig.10 shown.

[0084] Example 5

[0085] Reference Figure 1 , Figure 11 to Figure 13 In order to verify and illustrate the technical effect adopted in this method, the fuel cell stack is simulated using finite element simulation analysis software, and the data obtained after the simulation is compared with the data calculated using the present invention, that is, the calculation results are compared by means of scientific demonstration to verify the real effect of this method.

[0086] The graphite bipolar plate has a length of 426 mm, a width of 180 mm, a thickness of 2 mm, and a mass of 0.26876 kg.

[0087] The total number of plates is N = 100, the friction coefficient between the plates is f = 0.76, the clamping force of the battery stack is F = 30000N, E eff =35.87487MPa.

[0088] The calculation steps are as follows,

[0089] (1) According to the slip calculation formula:

[0090]

[0091] (2) Calculate the slip of the 25th plate:

[0092]

[0093] The simulation results are as follows Fig.11 , the slip amount is -0.00263551mm, and the fitting curve is as follows Fig.12 , and the error with the calculated result is within 2% Fig.13 As shown;

[0094] (3) Calculate the slip of the 60th plate:

[0095]

[0096] The simulation results are as follows Fig.11 , the slip amount is -0.00347355mm, and the fitting curve is as follows Fig.12 , and the error with the calculated result is within 2% Fig.13 shown.

[0097] Example 6

[0098] Reference Figure 1 , Figure 14 to Figure 16 In order to verify and illustrate the technical effect adopted in this method, the fuel cell stack is simulated using finite element simulation analysis software, and the data obtained after the simulation is compared with the data calculated using the present invention, that is, the calculation results are compared by means of scientific demonstration to verify the real effect of this method.

[0099] The graphite bipolar plate has a length of 426 mm, a width of 180 mm, a thickness of 2 mm, and a mass of 0.26876 kg.

[0100] The total number of plates is N = 200, the friction coefficient between the plates is f = 0.76, the clamping force of the battery stack is F = 20000N, E eff =123.8923MPa.

[0101] The calculation steps are as follows,

[0102] (1) According to the slip calculation formula:

[0103]

[0104] (2) Calculate the slip of the 75th plate:

[0105]

[0106] The simulation results are as follows Fig.14 , the slip amount is -0.01567149mm, and the fitting curve is as follows Fig.15 , and the error with the calculated result is within 1% Fig.16 As shown;

[0107] (3) Calculate the slip of the 174th plate:

[0108]

[0109] The simulation results are as follows Fig.14 , the slip amount is -0.0073458mm, and the fitting curve is as follows Fig.15 , and the error with the calculated result is within 5%. Fig.16 shown.

[0110] It can be seen from Examples 2-6 that the calculation method of the present invention can accurately predict the slippage of the fuel cell stack plate.

[0111] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for estimating slippage of a fuel cell stack plate, characterized in that: The following steps are included: Establish a fuel cell stack model; The plate closest to one end plate of the stack is the first plate, and the plate closest to the other end plate, i.e. the last plate, is the second plate. N slice, definition N is the total number of plates; The length of the plate side parallel to the direction of gravity in the working condition is b , and the length of the side perpendicular to it is a , the thickness of a single plate is c , the mass of a single plate is m ; Calculate the n The slip amount of the plate; No. n The calculation formula of the slip amount y of the plate is: ； in, E eff is the equivalent Young's modulus, with the opposite direction of gravity as the positive direction.

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