Hydrogen fuel cell cooling liquid as well as preparation method and application thereof

Abstract

The invention relates to hydrogen fuel cell cooling liquid as well as a preparation method and application thereof. The hydrogen fuel cell cooling liquid is prepared from the following components in percentage by mass: 9.5 to 61 percent of alcohol compound, 38.5 to 90 percent of water and 0.2 to 1 percent of boric acid. The technical problem to be solved is how to provide the hydrogen fuel cell cooling liquid with simplified components, so that the production cost is reduced, and the anti-freezing effect, low conductivity and low corrosion of the cooling liquid are maintained.

Description

Technical Field

[0001] The present invention belongs to the field of hydrogen fuel cells, and in particular relates to a hydrogen fuel cell coolant and a preparation method and application thereof. Background Art

[0002] A hydrogen fuel cell is composed of multiple stacked single cells. Each single cell has a bipolar plate and a membrane electrode forming "three chambers", including an anode chamber, a cathode chamber and a coolant chamber. The "two plates and three chambers" structure is the basic structural unit for the operation of the fuel cell stack, providing a place for hydrogen, oxygen and coolant to enter, exit, distribute and undergo chemical reactions.

[0003] Based on the structural unit and working principle of hydrogen fuel cells, it is necessary to ensure that the coolant has low conductivity, good thermal conductivity, and little metal corrosion. In particular, the low conductivity of the coolant is particularly demanding, and generally requires no more than 10us / cm to have an advantage. This is because low conductivity not only helps prevent electrochemical corrosion of the coolant, but also ensures that electrochemical stability is maintained. It is precisely because of the special requirements of hydrogen fuel cells for coolants that pure water is often used as coolant in the market. On the one hand, pure water can quickly achieve heat dissipation, and on the other hand, the conductivity of water meets the requirements of hydrogen fuel cells for coolants. The most important thing is that water is low in cost as a coolant, but pure water has a strong corrosion effect on the metal in the coolant chamber, and water has a weak antifreeze effect. For this reason, there are also documents that disclose that using ethylene glycol instead of water as a coolant can lower the freezing point of the coolant and reduce corrosion to metals. The gas in the hydrogen fuel cell may react with ethylene glycol to produce safety hazards such as combustion or explosion; therefore, the use of ethylene glycol coolant in the market is limited.

[0004] The latest literature has published a coolant, which adds triethanolamine borate to a coolant base liquid composed of water and ethylene glycol to prevent the coolant from freezing, and also adds compounds such as gelatin, azoles and lipids to the coolant for metal corrosion protection. In order to reduce the conductivity of the coolant, an ion inhibitor is also added. Although the anti-icing performance of the prepared coolant is improved, it has low conductivity and improved metal corrosion resistance, the preparation ingredients of the coolant are complex, which significantly increases the production cost. Summary of the invention

[0005] The main purpose of the present invention is to provide a hydrogen fuel cell coolant and its preparation method and application. The technical problem to be solved is how to provide a hydrogen fuel cell coolant with simplified components, reduce production costs, and maintain the coolant's anti-freezing effect, low conductivity performance, and low corrosiveness.

[0006] The purpose of the present invention and the technical problem solved are achieved by adopting the following technical solutions: According to the present invention, a hydrogen fuel cell coolant is composed of 9.5-61% alcohol compound, 38.5-90% water, and 0.2-1% boric acid in terms of mass percentage.

[0007] The purpose of the present invention and the solution to its technical problems can be further achieved by adopting the following technical measures.

[0008] Preferably, in the aforementioned coolant, the alcohol compound is selected from at least one of ethylene glycol, propylene glycol, and glycerol.

[0009] Preferably, in the aforementioned coolant, the water resistivity is greater than 18 megohms.

[0010] Preferably, in the aforementioned coolant, the alcohol compound is ethylene glycol, and the purity of the ethylene glycol is >99.9%.

[0011] Preferably, the aforementioned coolant, wherein the coolant is composed of 9.5-11% ethylene glycol, 88.5-90% water, and 0.4-0.8% boric acid; the freezing point of the coolant is -2.5 to -4°C.

[0012] Preferably, the aforementioned coolant, wherein the coolant is composed of 38.5-42% ethylene glycol, 57.5-61% water, and 0.2-0.5% boric acid; the freezing point of the coolant is -23 to -28°C.

[0013] Preferably, the aforementioned coolant, wherein the coolant is composed of 48.5-51% ethylene glycol, 48.5-51% water, and 0.2-0.5% boric acid; the freezing point of the coolant is -33 to -38°C.

[0014] Preferably, the aforementioned coolant, wherein the coolant is composed of 59-60.5% ethylene glycol, 39-40.5% water, and 0.2-0.5% boric acid; the freezing point of the coolant is -51 to -53°C.

[0015] The purpose of the present invention and the technical problem solved by the present invention are also achieved by adopting the following technical solutions. According to a method for preparing a hydrogen fuel cell coolant proposed by the present invention, the method comprises the following steps:

[0016] The alcohol compound and the boric acid aqueous solution are uniformly mixed to form a hydrogen fuel cell coolant;

[0017] Calculated by mass percentage, the hydrogen fuel cell coolant consists of 9.5-61% alcohol compounds, 38.5-90% water, and 0.2-1% boric acid.

[0018] The purpose of the present invention and the technical problems solved therein are also achieved by adopting the following technical solutions: A hydrogen fuel cell proposed in the present invention comprises a hydrogen fuel cell coolant prepared by the above-mentioned solution.

[0019] By means of the above technical solution, the present invention provides a hydrogen fuel cell coolant and a preparation method and application thereof, which have at least the following advantages:

[0020] 1. The present invention provides a hydrogen fuel cell coolant, which is composed of alcohol compounds, water and boric acid. The coolant components are simplified, and by adjusting the content of each component, the coolant not only has a lower freezing point, but also has low conductivity and corrosion resistance to metals. In addition, the coolant of the present invention has the effect of inhibiting the growth of algae and enhancing the antibacterial effect of the coolant. The hydrogen fuel cell coolant prepared by the present invention has simple components, low cost, and is easy to produce and use.

[0021] 2. The present invention also provides the freezing point of hydrogen fuel cell coolants prepared with different component ratios, so that different coolants can be selected to prepare hydrogen fuel cells for different geographical environments, and then prepared into equipment and devices containing hydrogen fuel cells to achieve the design purpose and further save costs.

[0022] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the preferred embodiments of the present invention are described in detail as follows. DETAILED DESCRIPTION

[0023] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a hydrogen fuel cell coolant and its preparation method and application proposed by the present invention in combination with the preferred embodiment. Its specific implementation method, structure, characteristics and effects are described in detail as follows.

[0024] The present invention provides a hydrogen fuel cell coolant, wherein alcohol compounds are added to water to increase the freezing point of the coolant, and boric acid is further added to synergistically act with the alcohol compounds to improve the corrosion resistance of the coolant; further, by adjusting the proportion of each component of the coolant, the coolant not only has a lower freezing point, but also has no obvious bubble generation; in addition, by adding an appropriate amount of alcohol and boric acid, the coolant also has a good antibacterial and algae growth inhibition effect. More importantly, since the coolant of the present invention has simple components and has little effect on the conductivity of the battery, the production cost is low and it is easy to produce and use.

[0025] Furthermore, the present invention adjusts the ratio of water, alcohol compounds and boric acid in the coolant, and develops coolants with different freezing points through a large number of experimental studies, so that the prepared coolant can be adapted to applications in different regions and environments, which is further conducive to saving production costs.

[0026] The present invention provides a hydrogen fuel cell coolant, which is composed of 9.5-61% alcohol compounds, 38.5-90% water, and 0.2-1% boric acid in terms of mass percentage. The present invention strictly limits the proportion of each component, so that the prepared coolant can not only reduce the freezing point, but also the coolant is not easy to have algae and bacteria breeding during long-term use. If the content of alcohol compounds is too high, not only the cost is increased, but also because the prepared hydrogen fuel cell contains a large amount of hydrogen and oxygen, its contact with the coolant may cause safety hazards; if the content of alcohol compounds is too low, the freezing point reduction effect of the coolant is not obvious. If the boric acid content is too high, the fluidity of the prepared coolant will be affected, affecting the heat transfer effect; if the boric acid content is too low, the prepared coolant may have poor antibacterial performance, and the coolant may have a strong corrosion effect on metals, which cannot achieve the design purpose.

[0027] In some embodiments of the above scheme, the alcohol compound is selected from at least one of ethylene glycol, propylene glycol and glycerol. Preferably, the coolant prepared from these alcohol compounds has a stronger effect of inhibiting algae growth and significantly reduces the freezing point of the coolant.

[0028] In some embodiments of the aforementioned scheme, it is preferred that the water resistivity is greater than 18 megohms, so that the coolant prepared has low conductivity.

[0029] In some embodiments of the above scheme, the alcohol compound is ethylene glycol, and the purity of the ethylene glycol is greater than 99.9%. The present invention preferably selects the purity and type of the alcohol compound to ensure that the freezing point of the coolant and the algae growth inhibition effect meet the preset requirements.

[0030] In some embodiments of the present invention, the cooling liquid is composed of the following components:

[0031] 9.5-11% ethylene glycol, 88.5-90% water, 0.4-0.8% boric acid; the freezing point of the coolant prepared under this condition is -2.5--4°C.

[0032] The hydrogen fuel cell prepared by the coolant of the aforementioned scheme, as well as the devices and equipment further prepared therefrom, can be used in areas with a winter environment of around zero degrees. Such devices and equipment not only have good antifreeze performance, but other performance can also meet the preset requirements. In addition, since the content of ethylene glycol and boric acid in the coolant is extremely small, the raw material input cost is reduced, making the production input cost of the coolant low and saving resources.

[0033] In some embodiments of the present invention, the cooling liquid is composed of the following components:

[0034] 38.5-42% ethylene glycol, 57.5-61% water, 0.2-0.5% boric acid; the freezing point of the coolant prepared under this condition is -23--28°C.

[0035] The hydrogen fuel cell prepared by the coolant of the aforementioned scheme, as well as the devices and equipment further prepared therefrom, can be used in areas with slightly cold ambient temperatures in winter. Such devices and equipment not only have good antifreeze performance, but other performance can also meet the preset requirements. In addition, due to the low content of ethylene glycol and boric acid in the coolant, the raw material input cost is reduced, making the production input cost of the coolant low and saving resources.

[0036] In some embodiments of the present invention, the cooling liquid is composed of the following components:

[0037] 48.5-51% ethylene glycol, 48.5-51% water, 0.2-0.5% boric acid; the freezing point of the coolant prepared under the conditions is -33--38°C.

[0038] The hydrogen fuel cell prepared by the coolant of the aforementioned scheme, and the further prepared devices and equipment, etc., can be used in areas with cold ambient temperatures in winter. Such devices and equipment not only have good antifreeze performance, but other performance can also meet the preset requirements. Although the coolant contains a large amount of ethylene glycol and boric acid, the minimum amount of coolant to achieve the antifreeze effect is still controlled, and the raw material input cost is still controlled to be low, which makes the production input cost of the coolant low and saves resources.

[0039] In some embodiments of the present invention, the cooling liquid is composed of the following components:

[0040] 59-60.5% ethylene glycol, 39-40.5% water, 0.2-0.5% boric acid; prepared under this condition -51--53°C.

[0041] The hydrogen fuel cell prepared by the coolant of the aforementioned scheme, as well as the devices and equipment further prepared therefrom, can be used in areas with extremely cold ambient temperatures in winter. Such devices and equipment not only have good antifreeze performance, but other performance can also meet the preset requirements. The content of ethylene glycol and boric acid in the coolant is greatly increased, but the minimum amount of coolant to achieve the antifreeze effect is still controlled, and the raw material input cost is still controlled to be low, so that the production input cost of the coolant is low, resources are saved, and the safety of battery use is guaranteed.

[0042] The present invention has found through a large number of experimental studies that the coolants prepared by adjusting the types of components and different component ratios required by the technical solution of the present invention have different freezing points. Therefore, when the coolant described in the present invention is used to prepare a hydrogen fuel cell, the corresponding coolant can be selected according to the characteristics of the geographical environment in which the hydrogen fuel cell is used. This not only enables the coolant to achieve antifreeze, antibacterial, and algae prevention effects, but also helps to save production costs.

[0043] The present invention also provides a method for preparing a hydrogen fuel cell coolant, which comprises the following steps:

[0044] Prepare a boric acid aqueous solution, which can be made by yourself or purchased. Some embodiments make a boric acid aqueous solution by making it yourself, and the specific method is as follows:

[0045] The alcohol compound and the boric acid aqueous solution are uniformly mixed by ultrasound or stirring to form a hydrogen fuel cell coolant. The frequency and time of ultrasound or the speed of stirring are not specifically limited, as long as they can be mixed uniformly. In terms of mass percentage, the hydrogen fuel cell coolant is composed of 9.5-61% alcohol compound, 38.5-90% water, and 0.2-1% boric acid.

[0046] Some embodiments of the present invention further provide a hydrogen fuel cell, which includes the hydrogen fuel cell coolant described in the aforementioned solution.

[0047] The invention provides a hydrogen fuel cell coolant and a preparation method thereof, which simplifies the components of the coolant, simplifies the preparation process, improves the production efficiency of the coolant, and reduces the production cost of the coolant, is easy to produce and use, and is conducive to large-scale production.

[0048] The present invention will be further described below in conjunction with specific embodiments, but this should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by technicians in this field based on the above-mentioned contents of the present invention still fall within the scope of protection of the present invention.

[0049] Unless otherwise specified, the materials, reagents, etc. involved below are all commercially available products well known to those skilled in the art; unless otherwise specified, the methods described are all methods well known in the art. Unless otherwise defined, the technical terms or scientific terms used should have the common meanings understood by ordinary technicians in the field to which the present invention belongs.

[0050] The purity of the ethylene glycol used in the embodiment of the present invention and the comparative example is greater than 99.9%, and the water is pure water, and its resistivity is greater than 18 megohms.

[0051] Example 1

[0052] This embodiment provides a hydrogen proton membrane fuel cell coolant and a preparation method and application thereof, specifically including:

[0053] 1) Prepare coolant

[0054] The boric acid and water are stirred and mixed evenly to form a boric acid aqueous solution.

[0055] The ethylene glycol and the boric acid aqueous solution are stirred and mixed evenly to obtain a hydrogen proton membrane fuel cell coolant. The prepared coolant contains 10% ethylene glycol, 89.2% water and 0.8% boric acid.

[0056] 2) Application

[0057] The coolant prepared in this embodiment is applied to a hydrogen proton membrane fuel cell, which is then installed on a car. The hydrogen fuel cell car is started at -1 to -2°C outdoors in winter; after the car is started, it runs for a total of 500 hours in the aforementioned temperature environment.

[0058] Coolant performance test:

[0059] Testing the freezing point of the coolant, the antifreeze performance of the coolant, the inhibition of algae growth and antibacterial effect, and the conductivity performance test. The test methods are as follows:

[0060] Coolant antifreeze property: Observe and record the lowest temperature when the car starts.

[0061] Algae growth inhibition test: observe the growth of algae in the coolant after the car has been running for 500 hours.

[0062] Corrosion: Observe the corrosion degree of the battery after the car has been running for 500 hours.

[0063] Antibacterial effect: Since a large number of bacteria will cause poor circulation of coolant, reduce cooling effect and cause uneven cooling, the circulation of coolant is observed to detect bacterial growth.

[0064] Coolant conductivity test: conductivity meter test.

[0065] Coolant freezing point detection method: Antifreeze freezing point detection standard SH / T0090.

[0066] The test results of various performances are shown in Table 1.

[0067] Example 2

[0068] This embodiment provides a hydrogen proton membrane fuel cell coolant and a preparation method and application thereof, specifically including:

[0069] 1) Prepare coolant

[0070] The boric acid and water are stirred and mixed evenly to form a boric acid aqueous solution.

[0071] The ethylene glycol and the boric acid aqueous solution are stirred and mixed evenly to obtain a hydrogen proton membrane fuel cell coolant. The prepared coolant contains 40% ethylene glycol, 59.5% water and 0.5% boric acid.

[0072] 2) Application

[0073] The coolant prepared in this embodiment was applied to a hydrogen proton membrane fuel cell, which was then installed in a car. The car was attempted to be started outdoors in winter at -10 to -15°C. After the car was started, it ran for a total of 500 hours in the aforementioned temperature environment.

[0074] Coolant performance test:

[0075] The freezing point test of the coolant, the antifreeze performance of the coolant, the algae growth inhibition effect and the antibacterial effect, and the conductivity performance test are tested. The test method is the same as in Example 1.

[0076] The test results of various performances are shown in Table 1.

[0077] Example 3

[0078] This embodiment provides a hydrogen proton membrane fuel cell coolant and a preparation method and application thereof, specifically including:

[0079] 1) Prepare coolant

[0080] The boric acid and water are stirred and mixed evenly to form a boric acid aqueous solution.

[0081] The ethylene glycol and the boric acid aqueous solution are stirred and mixed evenly to obtain a hydrogen proton membrane fuel cell coolant. The prepared coolant contains 50% ethylene glycol, 49.7% water and 0.3% boric acid.

[0082] 2) Application

[0083] The coolant prepared in this embodiment was applied to a hydrogen proton membrane fuel cell, which was then installed in a car. The car was attempted to be started outdoors at -20 to -25°C in winter, and the car ran for a total of 500 hours in the aforementioned temperature environment after starting.

[0084] Coolant performance test:

[0085] The freezing point test of the coolant, the antifreeze performance of the coolant, the algae growth inhibition effect and the antibacterial effect, and the conductivity performance test are tested. The test method is the same as in Example 1.

[0086] The test results of various performances are shown in Table 1.

[0087] Example 4

[0088] This embodiment provides a hydrogen proton membrane fuel cell coolant and a preparation method and application thereof, specifically including:

[0089] 1) Prepare coolant

[0090] Stirring and mixing boric acid and water to form a boric acid aqueous solution;

[0091] The ethylene glycol and the boric acid aqueous solution are stirred and mixed evenly to obtain a hydrogen proton membrane fuel cell coolant. The prepared coolant contains 60% ethylene glycol, 39.8% water and 0.2% boric acid.

[0092] 2) Application

[0093] The coolant prepared in this embodiment was applied to a hydrogen proton membrane fuel cell, which was then installed in a car. The car was attempted to be started outdoors at -35 to -50°C in winter, and the car ran for a total of 500 hours in the aforementioned temperature environment after starting.

[0094] Coolant performance test:

[0095] The freezing point test of the coolant, the antifreeze performance of the coolant, the algae growth inhibition effect and the antibacterial effect, and the conductivity performance test are tested. The test method is the same as in Example 1.

[0096] The test results of various performances are shown in Table 1.

[0097] Example 5

[0098] The difference between this embodiment and embodiment 1 is that the coolant contains 10% propylene glycol, 89.2% water and 0.8% boric acid. The rest of the process and method are the same as in embodiment 1.

[0099] Coolant performance test:

[0100] The freezing point test of the coolant, the antifreeze performance of the coolant, the algae growth inhibition effect and the antibacterial effect, and the conductivity performance test are tested. The test method is the same as in Example 1.

[0101] The test results of various performances are shown in Table 1.

[0102] Comparative Example 1

[0103] The difference between this comparative example and the embodiment is that:

[0104] The cooling liquid contains 10% ethylene glycol and 90% water. The remaining processes and methods are the same as those in Example 1.

[0105] The detection indexes and methods are the same as those in Example 1.

[0106] The test results of various performances are shown in Table 1.

[0107] Comparative Example 2

[0108] The difference between this comparative example and Example 1 is that the coolant contains 10% ethylene glycol, 89.9% water and 0.1% boric acid. The rest of the process and method are the same as Example 1.

[0109] The detection indexes and methods are the same as those in Example 1.

[0110] The test results of various performances are shown in Table 1.

[0111] Comparative Example 3

[0112] The difference between this comparative example and Example 1 is that the coolant contains 5.5% ethylene glycol, 94% water and 0.5% boric acid. The rest of the process and method are the same as Example 1.

[0113] The detection indexes and methods are the same as those in Example 1.

[0114] The test results of various performances are shown in Table 1.

[0115] Table 1 Performance test results of various embodiments and comparative examples

[0116]

[0117] Combining the embodiments and comparative examples and the data in Table 1, it can be seen that the hydrogen fuel cell coolant prepared by the present invention has simple ingredients, low production cost, greatly improved freezing point of the coolant, low electrical conductivity, strong inhibitory effect on algae, relatively strong inhibitory effect on bacteria, and relatively weak corrosion effect of the coolant on metals. Therefore, the coolant prepared by the present invention can be used for a long time.

[0118] Furthermore, it can be seen from the embodiments that the coolant required by the present invention can be used to adjust the freezing point of the coolant by adjusting the content of each component in the coolant. In this way, when the coolant is used to prepare a hydrogen fuel cell, the coolant can be customized accordingly according to the characteristics of the geographical environment in which the hydrogen fuel cell is used, thereby not only achieving the effects of antifreeze, antibacterial, and inhibiting algae growth, but also reducing production costs and saving resources.

[0119] The technical features in the claims and / or the specification of the present invention may be combined, and the combination is not limited to the combination obtained by reference in the claims. The technical solution obtained by combining the technical features in the claims and / or the specification is also within the protection scope of the present invention.

[0120] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A hydrogen fuel cell coolant, characterized in that: Calculated by mass percentage, the coolant consists of 9.5-61% alcohol compound, 38.5-90% water and 0.2-1% boric acid.

2. The coolant according to claim 1, characterized in that: The alcohol compound is selected from at least one of ethylene glycol, propylene glycol and glycerol.

3. The coolant according to claim 1, characterized in that: The water resistivity is >18 megohms.

4. The coolant according to claim 1, characterized in that: The alcohol compound is ethylene glycol, and the purity of the ethylene glycol is greater than 99.9%.

5. The coolant according to claim 4, characterized in that: The cooling liquid is composed of 9.5-11% ethylene glycol, 88.5-90% water and 0.4-0.8% boric acid; the freezing point of the cooling liquid is -2.5--4°C.

6. The coolant according to claim 1, characterized in that: The cooling liquid is composed of 38.5-42% ethylene glycol, 57.5-61% water and 0.2-0.5% boric acid; the freezing point of the cooling liquid is -23--28°C.

7. The coolant according to claim 1, characterized in that: The cooling liquid is composed of 48.5-51% ethylene glycol, 48.5-51% water, and 0.2-0.5% boric acid; the freezing point of the cooling liquid is -33--38°C.

8. The coolant according to claim 1, characterized in that The cooling liquid is composed of 59-60.5% ethylene glycol, 39-40.5% water and 0.2-0.5% boric acid; the freezing point of the cooling liquid is -51-53°C.

9. A method for preparing a hydrogen fuel cell coolant, characterized in that: It includes the following steps: The alcohol compound and the boric acid aqueous solution are mixed evenly to form a hydrogen fuel cell coolant; Calculated by mass percentage, the hydrogen fuel cell coolant consists of 9.5-61% alcohol compounds, 38.5-90% water, and 0.2-1% boric acid.

10. A hydrogen fuel cell, characterized in that: It comprises the hydrogen fuel cell coolant prepared according to any one of claims 1 to 9.

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