Mineral type energy storage cooling liquid composition and preparation method thereof

Abstract

The invention relates to the technical field of electrochemical energy storage, in particular to a mineral type energy storage cooling liquid composition and a preparation method thereof.The mineral type energy storage cooling liquid composition is prepared from base oil and additives, the base oil is prepared from, by mass, 80%-100% of paraffin-based mineral oil and 0-20% of naphthenic mineral oil, and the additives comprise an antioxidant, a light stabilizer and an anti-foaming agent; the addition amount of the additive is 0-1% of the total mass of the base oil. The invention relates to a mineral type energy storage cooling liquid composition. According to the mineral type cooling liquid composition and the preparation method thereof provided by the invention, the mineral type cooling liquid composition is prepared by adding trace amounts of the antioxidant, the light stabilizer and the defoaming agent into the mineral type base oil, the mineral type cooling liquid composition has relatively high flash point and breakdown voltage and relatively good low-temperature fluidity, and the cooling performance is effectively improved; and the cable also has good insulativity, fireproof safety and stability.

Description

Technical Field

[0001] The invention relates to the technical field of electrochemical energy storage, and is a mineral type energy storage coolant composition and a preparation method thereof. Background Art

[0002] Energy storage is a carrier of electric energy. The energy storage system can be used for grid peak regulation, effectively smoothing the volatility caused by large-scale new energy power generation connected to the grid, and improving the safety, economy and flexibility of grid operation. Energy storage technology has become the core key to building smart grids and realizing renewable energy power generation. At present, energy storage methods are mainly divided into mechanical energy storage, electrochemical energy storage, electromagnetic energy storage and phase change energy storage. Due to the advantages of low investment, high efficiency and simple maintenance, electrochemical energy storage has gradually become the mainstream development direction of new energy storage.

[0003] As an important part of the container energy storage system, the battery pack directly affects the performance of the entire system. Inside the container energy storage system, thousands of batteries are closely arranged, and the heat dissipation space is very limited. When the system is running, the battery charging and discharging will generate a lot of heat, which will cause uneven heat accumulation and cause temperature differences between batteries. Large temperature differences will cause inconsistent internal resistance and capacity of each battery. As time accumulates, some batteries will eventually be overcharged or over-discharged, affecting the life and performance of the entire system. Energy storage batteries generate a lot of heat during the charging and discharging process, and there is a risk of battery combustion or explosion. Therefore, research on battery cooling is particularly important.

[0004] At present, the mainstream energy storage battery cooling methods in the market are mostly air cooling and cold plate liquid cooling with water + ethylene glycol as the medium. Among them, the air cooling of the energy storage system mostly adopts the thermal management solution of air conditioning combined with cooling air duct air supply. The cooling air duct mainly plays a drainage role, and its function is to reasonably transport the airflow used for cooling to the battery pack that needs to be cooled. Air cooling mainly uses air conditioning for refrigeration, and the cooling medium is air, which has a low energy efficiency ratio. Therefore, the air-cooled equipment occupies a large area, resulting in low capacity density; secondly, the battery temperature uniformity is poor and the adaptability to harsh environments such as salt spray and wind and sand is poor. The cold plate liquid cooling structure with water + ethylene glycol as the medium adopts the combination of battery and cold plate, and transfers heat to the cooling medium through the radiator for heat exchange. The heat exchange method is single-sided heat exchange. The heat needs to be transferred to the cooling medium through the battery module box shell and the cold plate, and then the cooling medium dissipates the heat through the radiator. There are many links in the heat transfer, the thermal resistance is large, and the heat exchange efficiency is low, resulting in high requirements for the performance of the radiator, and the battery energy density cannot be efficiently improved. For battery packs, since the batteries are arranged closely and the gaps are small, the heat generated by the batteries cannot be quickly discharged, resulting in heat accumulation and large operating temperature differences. If things go on like this for a long time, the internal resistance and capacity between batteries will be inconsistent, seriously affecting the performance and life of the energy storage battery and causing safety hazards.

[0005] Among the patent documents on energy storage coolants in the field of electrochemical energy storage disclosed in China, the Chinese patent document with publication number CN114497802A discloses an immersion liquid-cooled battery energy storage system and its working method, in which the temperature regulating insulating liquid and firefighting coolant used are both fluorinated liquids. However, the disadvantages of fluorinated liquids are that the product is volatile, has poor biodegradability, is easily decomposed at high temperatures to produce highly toxic hydrogen fluoride and fluoroisobutylene, and is expensive. Summary of the invention

[0006] The present invention provides a synthetic oil type energy storage coolant composition and a preparation method thereof, which overcomes the above-mentioned deficiencies of the prior art and can effectively solve the problems of low heat exchange efficiency, poor biodegradability and high price of the existing cooling medium.

[0007] One of the technical solutions of the present invention is achieved through the following measures: a mineral energy storage coolant composition, the raw materials include base oil and additives, the base oil includes 80% to 100% paraffin-based mineral oil and 0 to 20% cycloalkyl mineral oil by mass percentage, the additives include antioxidants, light stabilizers, and anti-foaming agents, and the amount of additives added is 0 to 1% of the total mass of the base oil.

[0008] The following is a further optimization and / or improvement of one of the above-mentioned technical solutions: The amount of the above-mentioned additives added is 0.1% to 1.0% of the total mass of the base oil, the amount of the antioxidant added is 0.1% to 0.8% of the total mass of the base oil, the amount of the light stabilizer added is 0.01% to 0.1% of the total mass of the base oil, and the amount of the anti-foaming agent added is 0.0001% to 0.001% of the total mass of the base oil.

[0009] The above base oil has a kinematic viscosity of 18mm² / s to 24mm² / s at 40°C, a flash point greater than 200°C, a pour point below -25°C, a breakdown voltage greater than 60kV, a thermal conductivity (25°C) greater than 0.135W / m·k, a biodegradability greater than 60%, and an acute oral toxicity median lethal dose LD 50 Greater than 5000mg / kg, initial distillation point greater than 330℃.

[0010] The above antioxidant is a phenolic antioxidant and / or an amine antioxidant.

[0011] The light stabilizer is one or two of benzophenone stabilizers, salicylic acid stabilizers, benzotriazole stabilizers, and hindered amine derivatives.

[0012] The antifoaming agent is one or two of polydimethylsiloxane, polyacrylate, polymethacrylate, silicon-based compound and non-silicon-based compound.

[0013] The antioxidant is one or two of 2,6-di-tert-butyl-p-cresol, 4,4-methylenebis(2,6-di-tert-butylphenol), phenyl-α-naphthylamine and alkyl diphenylamine.

[0014] The antifoaming agent is polyether-modified silicone oil and / or silicone oil with an average molecular weight of 60,000 to 80,000.

[0015] The above-mentioned paraffin-based lubricating oil is obtained by first subjecting paraffin-based crude oil to atmospheric and vacuum distillation to obtain a 350°C to 420°C fraction, and then processed using the "hydrogenation treatment - isomerization dewaxing - additional refining" process. The kinematic viscosity of the base oil at 40°C is 18mm² / s to 24mm² / s, and the pour point is less than -20°C.

[0016] The mineral energy storage coolant composition is prepared by the following method: adding the required amount of antioxidant, light stabilizer and antifoaming agent to the base oil, stirring and mixing at 60°C to 80°C to obtain the mineral energy storage coolant composition.

[0017] The second technical solution of the present invention is achieved through the following measures: a method for preparing a mineral energy storage coolant composition, which is carried out according to the following steps: adding the required amount of antioxidant, light stabilizer and antifoaming agent to the base oil, stirring and mixing at 60°C to 80°C to obtain a mineral energy storage coolant composition.

[0018] The present invention provides a mineral coolant composition and a preparation method thereof, which is prepared by adding a trace amount of antioxidant, light stabilizer and defoamer to a mineral base oil. The mineral coolant composition has a high flash point and breakdown voltage, good low-temperature fluidity, and effectively improves the cooling performance while also having good insulation, fire safety and stability. DETAILED DESCRIPTION

[0019] The present invention is not limited by the following embodiments, and the specific implementation method can be determined according to the technical scheme of the present invention and the actual situation. Unless otherwise specified, the various chemical reagents and chemicals mentioned in the present invention are all known and commonly used chemical reagents and chemicals in the prior art; unless otherwise specified, the percentages in the present invention are all mass percentages; the normal temperature and room temperature in the present invention generally refer to the temperature of 15°C to 25°C, and are generally defined as 25°C.

[0020] The present invention will be further described below in conjunction with embodiments: Example 1: The mineral energy storage coolant composition, the raw materials include base oil and additives, the base oil includes 80% to 100% paraffin-based mineral oil and 0 to 20% cycloalkyl mineral oil by mass percentage, the additives include antioxidants, light stabilizers, and anti-foaming agents, and the amount of additives added is 0 to 1% of the total mass of the base oil.

[0021] The mineral energy storage coolant composition provided by the present invention has a lower pour point and a higher flash point by optimizing the selection and proportion of base oil, and has good insulation performance, and can be suitable for rapid cooling of electrochemical energy storage systems.

[0022] Example 2: As an optimization of the above example, the amount of additive added is 0.1% to 1.0% of the total mass of the base oil, the amount of antioxidant added is 0.1% to 0.8% of the total mass of the base oil, the amount of light stabilizer added is 0.01% to 0.1% of the total mass of the base oil, and the amount of antifoaming agent added is 0.0001% to 0.001% of the total mass of the base oil.

[0023] Example 3: As an optimization of the above example, the base oil has a kinematic viscosity at 40°C of 18 mm² / s to 24 mm² / s, a flash point greater than 200°C, a pour point lower than -25°C, a breakdown voltage greater than 60 kV, a thermal conductivity (25°C) greater than 0.135 W / m·k, a biodegradability greater than 60%, and an acute oral toxicity median lethal dose LD 50 The concentration is greater than 5000 mg / kg and the initial boiling point is greater than 330°C. The base oil can meet the cooling requirements of the electrochemical energy storage system.

[0024] Example 4: As an optimization of the above example, the antioxidant is a phenolic antioxidant and / or an amine antioxidant.

[0025] Embodiment 5: As an optimization of the above embodiment, the light stabilizer is one or two of benzophenone stabilizers, salicylic acid stabilizers, benzotriazole stabilizers, and hindered amine derivatives.

[0026] Embodiment 7: As an optimization of the above embodiment, the anti-foaming agent is one or two of polydimethylsiloxane, polyacrylate, polymethacrylate, silicon-based compound and non-silicon-based compound.

[0027] Example 8: As an optimization of the above example, the antioxidant is one or two of 2,6-di-tert-butyl-p-cresol, 4,4-methylenebis(2,6-di-tert-butylphenol), phenyl-α-naphthylamine, and alkyl diphenylamine.

[0028] Embodiment 9: As an optimization of the above embodiment, the anti-foaming agent is polyether-modified silicone oil and / or silicone oil with an average molecular weight of 60,000 to 80,000.

[0029] Example 10: As an optimization of the above example, naphthenic mineral oil is first obtained by distilling naphthenic crude oil at atmospheric and vacuum conditions to obtain a fraction of 330°C to 380°C, and then processed by the process of "hydrogenation treatment - hydrodecondensation - supplementary refining - precision fractionation". Specifically, the process conditions for preparing naphthenic base oil are as follows: hydrotreatment process: pressure 16MPa to 18MPa, temperature 330°C to 400°C, catalyst LH-23; hydrodecondensation process: pressure 16MPa to 18MPa, temperature 250°C to 290°C, catalyst RDW-1; supplementary refining process: pressure 16MPa to 18MPa, temperature 220°C to 300°C, catalyst RJW-2.

[0030] Example 11: As an optimization of the above example, the mineral energy storage coolant composition is prepared by the following method: Add the required amount of antioxidant, light stabilizer and antifoaming agent to the base oil, stir and mix evenly at 60°C to 80°C to obtain the mineral energy storage coolant composition.

[0031] The mineral energy storage coolant composition of the present invention is prepared by adding a trace amount of antioxidant, light stabilizer and defoamer to the mineral base oil, and has a high flash point and breakdown voltage, good low-temperature fluidity, and also has good insulation, fire safety and stability. When used, the coolant can be forced to circulate through liquid cooling technology to improve the heat dissipation efficiency, reduce the temperature difference of the battery core to control the temperature difference of the lithium battery system, and achieve the purpose of uniform temperature inside the energy storage system.

[0032] Example 12 to Example 16: Cycloalkyl mineral oil and paraffin-based mineral oil are mixed according to the formula and amount in Table 1, the mixing and stirring temperature is 60°C to 80°C, and after fully mixing, a base oil is obtained; an antioxidant, a light stabilizer and an antifoaming agent are added to the base oil in sequence, and then stirred and mixed to obtain a mineral energy storage coolant composition, the formula of which is shown in Table 1. In Table 1, the amount of antioxidant, light stabilizer and antifoaming agent added is the percentage of the total mass of the base oil.

[0033] The properties of the mineral energy storage coolant compositions prepared in Examples 12 to 16 were tested, and the test results are shown in Table 2. From Table 2, it can be seen that the mineral energy storage coolant compositions in Examples 12 to 16 have excellent oxidation stability, good low-temperature performance, high electrical insulation performance, good heat transfer performance, good biodegradability and low toxicity under the premise of ensuring a high flash point in terms of safety.

[0034] In summary, the present invention provides a mineral coolant composition and a preparation method thereof, which prepares the coolant by adding a trace amount of antioxidant, light stabilizer and defoamer to the traditional mineral base oil, and effectively improves the various properties of the coolant. The coolant of the present invention has a high flash point and breakdown voltage, good low-temperature fluidity, and effectively improves the cooling performance while also having good insulation, fire safety and stability, and can be suitable for immersion direct cooling of electrochemical energy storage systems.

[0035] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the requirements of different situations.

Claims

1. A mineral energy storage coolant composition, characterized in that The raw materials include base oil and additives. The base oil includes 80% to 100% paraffin-based mineral oil and 0 to 20% cycloalkyl mineral oil in terms of mass percentage. The additives include antioxidants, light stabilizers, and anti-foaming agents. The amount of additives added is 0 to 1% of the total mass of the base oil.

2. The mineral energy storage coolant composition according to claim 1, characterized in that The amount of additives added is 0.1% to 1.0% of the total mass of the base oil, the amount of antioxidant added is 0.1% to 0.8% of the total mass of the base oil, the amount of light stabilizer added is 0.01% to 0.1% of the total mass of the base oil, and the amount of anti-foaming agent added is 0.0001% to 0.001% of the total mass of the base oil.

3. The mineral energy storage coolant composition according to claim 1 or 2, characterized in that The base oil has a kinematic viscosity of 18 mm² / s to 24 mm² / s at 40°C, a flash point greater than 200°C, a pour point below -25°C, a breakdown voltage greater than 60 kV, a thermal conductivity greater than 0.135 W / m·k, a biodegradability greater than 60%, and an acute oral toxicity median lethal dose LD 50 Greater than 5000mg / kg, initial distillation point greater than 330℃.

4. The mineral energy storage coolant composition according to any one of claims 1 to 3, characterized in that The light stabilizer is one or two of benzophenone stabilizers, salicylic acid stabilizers, benzotriazole stabilizers, and hindered amine derivatives.

5. The mineral energy storage coolant composition according to any one of claims 1 to 4, characterized in that The antioxidant is a phenolic antioxidant and / or an amine antioxidant.

6. The mineral energy storage coolant composition according to any one of claims 1 to 5, characterized in that The anti-foaming agent is one or two of polydimethylsiloxane, polyacrylate, polymethacrylate, silicon-based compound and non-silicon-based compound.

7. The mineral energy storage coolant composition according to any one of claims 1 to 6, characterized in that The antioxidant is one or two of 2,6-di-tert-butyl-p-cresol, 4,4-methylenebis(2,6-di-tert-butylphenol), phenyl-α-naphthylamine, and alkyl diphenylamine; or / and, the anti-foaming agent is polyether-modified silicone oil or / and silicone oil with an average molecular weight of 60,000 to 80,000.

8. The mineral energy storage coolant composition according to any one of claims 1 to 7, characterized in that Naphthenic mineral oil is obtained by distilling naphthenic crude oil at atmospheric and vacuum conditions to obtain a fraction at 330°C to 380°C, and then processing it using the process of "hydrogenation treatment - hydrodecondensation - additional refining - precision fractionation".

9. The mineral energy storage coolant composition according to any one of claims 1 to 8, characterized in that The preparation method is as follows: adding the required amount of antioxidant, light stabilizer and antifoaming agent into the base oil, stirring and mixing at 60° C. to 80° C. to obtain a mineral energy storage coolant composition.

10. A method for preparing the mineral energy storage coolant composition according to any one of claims 1 to 8, characterized in that Add the required amount of antioxidant, light stabilizer and antifoaming agent into the base oil, stir and mix evenly at 60° C. to obtain a mineral energy storage coolant composition.

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