Cooling liquid for hydrogen fuel cell automobile

Abstract

The invention relates to the technical field of cooling liquids, in particular to a cooling liquid for hydrogen fuel cell automobiles, which comprises the following components: a base liquid and an antirust agent, the base liquid comprises deionized water and an antifreezing agent, the antifreezing agent is monohydric alcohol or dihydric alcohol, and the antirust agent is an organic solvent. The antirust agent comprises one or a combination of more of a triazole compound, an imidazole compound and a thiazole compound, an amide compound and a silicate ester compound, and the compound combination of the triazole compound, the amide compound and the estersil compound can achieve the same slow release effect as a traditional cooling liquid composition; the metal material of the fuel cell stack cooling system has excellent anti-rust performance while low conductivity is ensured.

Description

Technical Field

[0001] The invention relates to a coolant for a hydrogen fuel cell vehicle, belonging to the technical field of coolants. Background Art

[0002] A fuel cell is composed of a single cell stack. In order to cool the stack, a bipolar plate must be inserted for heat dissipation. There are channels for coolant to flow through the bipolar plate. The coolant flows through the holes and takes away the heat of the stack. The coolant flows in the stack. If the conductivity of the coolant is high, the current generated in the stack will flow to the coolant, causing the power generation efficiency of the fuel cell system to decrease. Therefore, low-conductivity coolant should be used in the fuel cell system. In addition to the conductivity requirements, the fuel cell system contains materials such as stainless steel, 3-series aluminum, 4-series aluminum and 6-series aluminum, so the coolant is also required to have good anti-rust properties.

[0003] A waterless engine coolant disclosed in (CN102002347B) is characterized by containing the following components in weight percentage: 10-80% ethylene glycol, 10-80% propylene glycol, 5-20% polyol, 0.1-0.8% phosphoric acid-molybdate, 0.2-0.9% silicate, 0.1-1% 4-methyl 1H-benzotriazole, 0.2-0.8% citric acid, 0.2-1% sebacic acid, 0.1-1% octanoic acid, 0.4-1.2% citrate, and 0.01-0.2% cosolvent. The coolant has a freezing point of -30 to -50°C and a boiling point of 130 to 150°C, ensuring the cold start of the engine in cold weather, while the working temperature is increased from the original 85 to 95°C to 95 to 150°C. The coolant is a non-aqueous system, which avoids electrochemical corrosion. At the same time, the coolant is a buffer system with a pH of 7.5-9.5. The added additives have an active anti-corrosion effect on aluminum, aluminum alloys and copper.

[0004] The existing technology generally uses inorganic salt and organic acid corrosion inhibitors, including nitrates, phosphates, nitrites, molybdates, silicates, borates, and combinations of monobasic and dibasic acids with 8-12 carbon atoms, which do not have good anti-rust properties for the metal materials of the fuel cell stack cooling system. Summary of the invention

[0005] The object of the present invention is to provide a coolant for hydrogen fuel cell vehicles, which adopts a composite combination of azole compounds, amide compounds and silicone ester compounds to achieve the same sustained-release effect as a traditional coolant composition and has the characteristics of low conductivity.

[0006] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0007] A coolant for hydrogen fuel cell vehicles, comprising the following components: a base liquid and a rust inhibitor, wherein the base liquid contains deionized water and an antifreeze agent, the antifreeze agent is a monohydric alcohol or a dihydric alcohol, and the rust inhibitor comprises one or more combinations of triazole compounds, imidazole compounds and thiazole compounds, as well as amide compounds and silicate compounds.

[0008] Preferably, the volume ratio of the deionized water to the antifreeze agent is 1:1.

[0009] Preferably, the antifreeze agent is diol, and the weight ratio of the rust inhibitor to the diol is 0.001-5%.

[0010] Preferably, the diol is ethylene glycol or propylene glycol.

[0011] Preferably, the triazole compound is one or more of benzotriazole, methylbenzotriazole and ethylbenzotriazole.

[0012] Preferably, the thiazole compound is one or both of mercaptothiazole and mercaptothiadiazole.

[0013] Preferably, the amide compound is one or more of formamide, acetamide, caprolactam and benzamide.

[0014] Preferably, an anti-foaming agent is also included.

[0015] The present invention has at least the following beneficial effects:

[0016] 1. The significant difference between the present invention and the traditional coolant composition is that the present invention does not use inorganic salts and organic acid corrosion inhibitors, including nitrates, phosphates, nitrites, molybdates, silicates, borates, monobasic acids with 8-12 carbon atoms and dibasic acid combinations. The present invention uses a composite combination of azole compounds, amide compounds and silicone ester compounds to achieve the same slow-release effect as the traditional coolant composition, while ensuring low conductivity and providing excellent rust prevention performance for the metal materials of the fuel cell stack cooling system. DETAILED DESCRIPTION

[0017] The following will explain the implementation methods of the present application in detail with reference to examples, so that the implementation process of how the present application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0018] The invention relates to a coolant for hydrogen fuel cell vehicles, comprising the following components: a base liquid and a rust inhibitor, wherein the base liquid contains deionized water and an antifreeze agent, the antifreeze agent is a monohydric alcohol or a dihydric alcohol, and the rust inhibitor comprises one or more combinations of triazole compounds, imidazole compounds and thiazole compounds, as well as amide compounds and silicate compounds.

[0019] Furthermore, the volume ratio of deionized water to antifreeze is 1:1; the antifreeze is diol, and the weight ratio of the rust inhibitor to the diol is 0.001-5%.

[0020] Preferably, the diol is ethylene glycol or propylene glycol, the triazole compound is one or more of benzotriazole, methylbenzotriazole and ethylbenzotriazole; the thiazole compound is one or both of mercaptothiazole and mercaptothiadiazole; and the amide compound is one or more of formamide, acetamide, caprolactam and benzamide.

[0021] The composition of the present invention may be added with an antifoaming agent without affecting the conductivity.

[0022] The composition of the present invention is further described according to the examples. Table 1 shows Examples 1 to 6 (deionized water and ethylene glycol each account for 50% by volume), wherein Control Example 1 is a water-ethylene glycol mixture (each account for 50% by volume).

[0023] The composition of the present invention contains a base liquid and an anti-rust additive combination, which maintains the coolant with low conductivity while maintaining excellent anti-rust properties. Table 1 is an example scheme (the red font represents the weight ratio of the compound to ethylene glycol). Table 2 The metal corrosion test is carried out according to SH / T 0085, the temperature is 80°C, and the time is 336h.

[0024] Table 1 Example Scheme

[0025]

[0026]

[0027] Embodiment 1:

[0028] A cooling liquid for hydrogen fuel cell vehicles comprises 50% by volume of deionized water, 50% by volume of ethylene glycol, benzotriazole (accounting for 0.003% by weight of ethylene glycol), benzamide (accounting for 0.001% by weight of ethylene glycol) and tetraethylsilane (accounting for 0.002% by weight of ethylene glycol).

[0029] Embodiment 2:

[0030] A coolant for hydrogen fuel cell vehicles, comprising 50% by volume of deionized water, 50% by volume of ethylene glycol, benzotriazole (accounting for 0.002% by weight of ethylene glycol), benzamide (accounting for 0.003% by weight of ethylene glycol), mercaptothiadiazole (accounting for 0.005% by weight of ethylene glycol) and tetraethylsilane (accounting for 0.005% by weight of ethylene glycol).

[0031] Embodiment three:

[0032] A coolant for hydrogen fuel cell vehicles, comprising 50% by volume of deionized water, 50% by volume of ethylene glycol, benzotriazole (accounting for 0.001% by weight of ethylene glycol), benzamide (accounting for 0.004% by weight of ethylene glycol), methylimidazole (accounting for 0.002% by weight of ethylene glycol) and tetraethylsilane (accounting for 0.003% by weight of ethylene glycol).

[0033] Embodiment 4:

[0034] A coolant for hydrogen fuel cell vehicles, comprising 50% by volume of deionized water, 50% by volume of ethylene glycol, benzotriazole (accounting for 0.004% by weight of ethylene glycol), benzamide (accounting for 0.002% by weight of ethylene glycol), mercaptothiadiazole (accounting for 0.003% by weight of ethylene glycol), methylimidazole (accounting for 0.003% by weight of ethylene glycol) and tetraethylsilane (accounting for 0.001% by weight of ethylene glycol).

[0035] Embodiment five:

[0036] A coolant for hydrogen fuel cell vehicles, comprising 50% by volume of deionized water, 50% by volume of ethylene glycol, benzotriazole (accounting for 0.002% by weight of ethylene glycol), benzamide (accounting for 0.003% by weight of ethylene glycol), mercaptothiadiazole (accounting for 0.001% by weight of ethylene glycol), methylimidazole (accounting for 0.001% by weight of ethylene glycol) and tetraethylsilane (accounting for 0.002% by weight of ethylene glycol).

[0037] Table 2 Example test results

[0038]

[0039] As can be seen from Table 2, the initial conductivity of Examples 1-5 is less than 2uS / cm, and the initial conductivity of Comparative Example 1 is 0.5uS / cm. After the metal corrosion test, the conductivity of the comparative example was increased to 45.2uS / cm, while the solution conductivity of Examples 1-5 after the test did not exceed 20uS / cm, which shows that the combination of the rust inhibitor system of Examples 1-5 has an inhibitory effect on the growth of the conductivity of the coolant. The weight change of the metal test piece shows that the aluminum material in Comparative Example 1 has a significant weight loss phenomenon, and the minimum weight loss of the test piece is more than 17mg, while Examples 1-5 have better ability to inhibit metal corrosion.

[0040] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. For example, "including" mentioned throughout the specification and claims is an open term, so it should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve technical problems within a certain error range and basically achieve technical effects.

[0041] It should be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0042] The above description shows and describes several preferred embodiments of the present invention, but as mentioned above, it should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the invention concept described herein through the above teachings or the technology or knowledge of the relevant field. Changes and variations made by those skilled in the art do not depart from the spirit and scope of the present invention, and should be within the scope of protection of the claims attached to the present invention.

Claims

1. A coolant for hydrogen fuel cell vehicles, comprising the following components: a base liquid and a rust inhibitor, wherein the base liquid contains deionized water and an antifreeze agent; The antifreeze agent is a monohydric alcohol or a dihydric alcohol; The rust inhibitor includes one or more combinations of triazole compounds, imidazole compounds and thiazole compounds, as well as amide compounds and silicate compounds.

2. The coolant for hydrogen fuel cell vehicles according to claim 1, characterized in that: The volume ratio of the deionized water to the antifreeze agent is 1:

1.

3. The coolant for hydrogen fuel cell vehicles according to claim 1, characterized in that: The antifreeze agent is diol, and the weight ratio of the rust inhibitor to the diol is 0.001-5%.

4. The coolant for hydrogen fuel cell vehicles according to claim 3, characterized in that: The diol is ethylene glycol or propylene glycol.

5. The coolant for hydrogen fuel cell vehicles according to claim 1, characterized in that: The triazole compound is one or more of benzotriazole, methylbenzotriazole and ethylbenzotriazole.

6. The coolant for hydrogen fuel cell vehicles according to claim 1, characterized in that: The imidazole compound is one or more of methyl imidazole, ethyl imidazole and propyl imidazole.

7. The coolant for hydrogen fuel cell vehicles according to claim 1, characterized in that: The thiazole compound is one or both of mercaptothiazole and mercaptothiadiazole.

8. The coolant for hydrogen fuel cell vehicles according to claim 4, characterized in that: The amide compound is one or more of formamide, acetamide, caprolactam and benzamide.

9. The coolant for hydrogen fuel cell vehicles according to claim 5, characterized in that: The silicate compound is one or more of tetramethyl silicate, tetraethyl silicate, tetrapropyl silicate and tetrabutyl silicate.

10. A coolant for hydrogen fuel cell vehicles according to any one of claims 1 to 9, characterized in that: Anti-foaming agents are also included.

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