JP7191803B2 - Heat storage material composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heat storage material composition that can be used to control the temperature of a refrigerant in a cooling circuit for cooling a heat source such as a motor, a battery of a secondary battery, or a fuel cell. The present invention relates to a heat storage material composition suitable for temperature control.

2. Description of the Related Art Electrical components such as motors and batteries mounted in vehicles such as automobiles and automotive components generate more heat as their output increases. For this reason, it is an important issue to improve the cooling performance corresponding to the increase in the amount of heat generated. In particular, motors, batteries of secondary cells, fuel cells, and the like, if the amount of heat generated becomes too large, damage or deterioration may occur, resulting in reduced performance.

That is, a cooling circuit is formed around a motor, a secondary battery, a fuel cell, etc., which are heat sources (for example, in the case of a secondary battery, a fuel cell, etc., in the case, that is, in the pack or stack). is formed inside the cooling circuit), and cooling is performed by a refrigerant system in which a refrigerant flows through the cooling circuit. Since the temperature rises rapidly, cooling cannot be done in time due to the rapid temperature rise of the coolant, and there is a risk that the performance of the motor, the secondary battery, the fuel cell, etc., will be overheated, resulting in reduced performance or malfunction. Especially in summer when the temperature is high, the temperature rises immediately even with a short-time load, and there is a risk of damage or burnout. Therefore, there is a demand for a cooling technique capable of controlling the temperature to a higher degree.

On the other hand, by designing a cooling system with a high cooling capacity in accordance with the temporary high heat generation during high load and rapid charging, for example, by increasing the number of cooling circuits and using pressurized refrigerant, , cooling fans, Peltier elements, heat pipes, heat sinks, and other heat exchangers can be combined to improve the cooling performance. Even in normal conditions with little air content, excessive cooling results in excessive quality, which not only increases costs, but also increases the size, size, and complexity of the cooling system. It becomes unsupportable. They also lead to increased power consumption.

Therefore, the present inventors are pursuing a cooling system that enables effective cooling even during high heat generation such as during high load or rapid charging without enlarging the existing cooling system. The idea was to absorb and store heat energy transmitted from a heat source such as a motor, battery, or fuel cell to a coolant in a cooling circuit in a heat storage material.
Here, as heat storage materials, there are chemical heat storage materials, sensible heat storage materials, latent heat storage materials, and the like. A latent heat type (phase change type) heat storage material, which has latent heat when the phase of the material changes at a specific temperature, is often used.

However, with such a latent heat storage material, the output temperature (phase transition temperature) is constant and the heat storage temperature range is narrow. ) is limited to heat storage in the vicinity of
Therefore, the selection of a single material does not bring about the merits of heat absorption and heat storage in an environment with a temperature lower than the inherent melting point of the material. Furthermore, it is poor in adaptability to various cooling systems in which the optimum cooling temperature differs according to the type of heat source, the surrounding structure, etc., and cannot be widely applied. That is, when a latent heat storage material with a relatively high melting point is selected, the temperature rise of the refrigerant becomes high before the latent heat storage material undergoes a phase change, so the heat load on the cooling circuit, the heat source and its surroundings is high. become a thing. When a latent heat storage material with a relatively low melting point is selected, there is a possibility that the heat storage capacity will soon exceed the limit due to a rapid temperature rise of the refrigerant, and the temperature rise of the refrigerant cannot be effectively suppressed.

On the other hand, conventionally, when a plurality of types of latent heat storage materials with different melting points are mixed, there has been a problem that the heat storage amount is significantly reduced. Looking at the DSC curve measured by the differential scanning calorimeter at this time, the endothermic peak is broadened and the temperature range of the phase change is widened. It can be predicted that a heat storage loss occurs, or the heat storage function is lowered or deactivated due to a chemical reaction between materials, and therefore the heat storage amount is greatly reduced.

Here, as a technique for mixing multiple types of latent heat storage materials, Patent Document 1 discloses multiple types of gel balls made of multiple types of organic phase transition materials with different melting points and whose surfaces are coated with a hydrophobic material as a dispersion medium. Disclosed is an emulsion-type heat storage with multiple phase transition temperatures due to dispersion therein. In the technique of Patent Document 1, the phase change material is turned into granular gel balls, and the surfaces of the gel balls are coated with a hydrophobic material, so that the emulsion type heat storage material has a plurality of phase transition temperatures.

However, the technique of Patent Literature 1 requires gel ball formation of the phase transition material and surface treatment, which requires time and effort in manufacturing and increases the cost. In addition, gel balling and surface treatments are expected to lower overall heat storage.
Similarly, by microencapsulating the phase change material, it is possible to avoid the deterioration and deactivation of the heat storage function when combining a plurality of phase change materials. In addition, the overall heat storage is expected to be low due to voids in the capsule that are not filled with the phase change material. In addition, microencapsulation requires capsules, a cross-linking agent, and the like, which complicates the manufacturing process, resulting in high costs.

Furthermore, regarding the heat storage material, there are patent document 2 and patent document 3 as techniques capable of controlling the phase change temperature to a desired value.
Patent Document 2 discloses that 10 to 70% by weight of fatty acid or (and) higher alcohol having 10 or more carbon atoms is added to paraffin wax, and alkyl having 10 or more carbon atoms is added to the entire paraffin wax, fatty acid or (and) higher alcohol A heat storage material composition containing 5 to 50% by weight of a substituted fatty acid ester is disclosed.
Further, Patent Document 3 discloses that a mixture of a higher alcohol having 14 carbon atoms and paraffin wax is the main component, the weight ratio of the higher alcohol having 14 carbon atoms in the mixture is 75 to 95% by weight, and a differential scanning type Disclosed is a composition for a heat storage material that has substantially a single melting peak in a DSC curve measured by a calorimeter (DSC).

JP 2019-038975 A JP-A-5-39479 JP 2016-14088 A

Both of the techniques of Patent Document 2 and Patent Document 3 enable heat storage design at a desired temperature by mixing a predetermined higher alcohol with paraffin wax. In the DSC curve by , the number of melting peaks is one, the melting peak is in a single continuous temperature range, and the heat is stored in a specific single temperature range. Therefore, under conditions of rapid temperature rise, the heat storage capacity may soon exceed the limit, and the temperature rise of the refrigerant may not be effectively suppressed. In addition, it is inferior in versatility to various cooling systems whose temperature is designed according to the type of heat source, its surrounding structure, and the like.

Therefore, an object of the present invention is to provide a heat storage material composition that can obtain a high heat storage effect even when a plurality of phase change materials are mixed without being granulated, and can effectively suppress the temperature rise of the refrigerant. is.

The heat storage material composition of claim 1 has a melting point difference of 20° C. or higher and 40° C. or lower, preferably 22° C. or higher and 35° C. or lower, more preferably 24° C. or higher and 30° C. or lower. It consists of a mixture of paraffin wax and higher alcohols.

The paraffin wax is preferably a paraffin compound that is solid (solid) at room temperature. Here, the paraffin compound is a general term for aliphatic saturated hydrocarbons represented by the general formula C _n H _2n+2 (where n is not limited), and is also called alkanes and methane hydrocarbons. . For example, it is contained in petroleum, lubricating oil, etc. and is taken out by fractionation or refining, and is broadly understood to include normal paraffinic and isoparaffinic, regardless of the degree of fractionation or refining. is a blackish-brown heavy oil containing hydrocarbons and carbon, which is fractionated from the same petroleum, and does not include asphalt. Considering the amount of latent heat, normal paraffins (n-paraffins) in which all carbon atoms in the molecule are linear saturated hydrocarbons and the carbon skeleton does not have branched side chains are preferable. More preferably, normal paraffin having an even number of carbon atoms, 2n (where n is a number selected from natural numbers).

The higher alcohol is preferably a higher saturated fatty alcohol that is solid (solid) at room temperature, and has a melting point (phase transition point) that is 20° C. to 40° C. higher than the melting point of the paraffin wax. 22°C to 35°C, more preferably 24°C to 30°C, as long as it is low or high. In other words, the paraffin wax has a melting point higher or lower than that of the higher alcohol by 20°C to 40°C, preferably 22°C to 35°C, and still more preferably 24°C to 30°C. is.
These paraffins and higher alcohols function as a latent heat storage material (solid-liquid phase change type phase change material) that stores heat by the latent heat when the phase changes (melts) from the solid phase to the liquid phase.

The paraffin wax of the heat storage material composition of claim 1 has a melting point (phase transition point) of 65° C. or higher and 85° C. or lower, more preferably 70° C. or higher and 80° C. or lower. It is higher than the melting point of higher alcohols.

The paraffin wax of the heat storage material composition of the invention of claim 2 is mainly composed of n-hexatriacontane (nC ₃₆ H ₇₄ ), and is preferably highly purified with a purity of 80% or more. It is.

The higher alcohol of the heat storage material composition of the third aspect of the invention is a higher aliphatic alcohol having 13 or more and 18 or less carbon atoms, more preferably 14 or more and 18 or less carbon atoms. Preferred are higher saturated aliphatic alcohols having one hydroxy group at the terminal carbon, and aliphatic alcohols represented by CH ₃ (CH ₂ ) _m OH where m is 13 or more and 17 or less. More preferably, the melting point is in the range of 35° C. or higher and 60° C. or lower. For example, myristyl alcohol, 1-hexadecanol, and stearyl alcohol can be used.

The higher alcohol of the heat storage material composition of the invention of claim 4 is 1-hexadecanol (also called cetanol, cetyl alcohol, palmityl alcohol).

The heat storage material composition of the invention of claim 5 is a heat storage material with a low melting point ( The higher alcohol or the paraffin wax) is preferably 80 parts by mass or more and 550 parts by mass or less, more preferably 100 parts by mass or more and 500 parts by mass or less, and still more preferably 300 parts by mass or more and 500 parts by mass or less. It is a compound within the range of. In addition, the said compounding is compounding by the solid (solid) amount of a paraffin wax and a higher alcohol.

In the heat storage material composition of the invention of claim 6 , the total amount of the paraffin wax and the higher alcohol is 100 parts by mass, and the heat storage material having the higher melting point among the paraffin wax and the higher alcohol (the paraffin wax or the higher alcohol) is preferably 10 parts by mass or more and 60 parts by mass, more preferably 10 parts by mass or more and 55 parts by mass or less, and still more preferably 10 parts by mass or more and 30 parts by mass or less. , The heat storage material on the low melting point side (the higher alcohol or the paraffin wax) is preferably 40 parts by mass or more and 90 parts by mass or less, more preferably 45 parts by mass or more and 90 parts by mass or less, still more preferably It is within the range of 70 parts by mass or more and 90 parts by mass or less. The blending is based on the solid (solid) amount of the high-melting paraffin wax and the higher alcohol.

The heat storage material composition of the invention of claim 7 further contains a solid-solid phase transition type phase change material.
As the solid-solid phase change type phase change material (solid phase change type phase change material), for example, it has soft-viscous crystals and phase changes from the low temperature side crystals to the high temperature side crystals, that is, from the solid phase to the solid phase. Polyhydric alcohols such as trimethylolethane, pentaerythritol, and neopentyl glycol that undergo first-order phase transition to phases, metal oxides such as vanadium and barium (vanadium oxide, titanium oxide, barium oxide, etc.), vanadium sulfide, etc. can be used.

The solid-solid phase transition type phase change material of the heat storage material composition of claim 8 is trimethylolethane (C ₅ H ₁₂ O ₃ ).

The solid-solid phase transition type phase change material of the heat storage material composition of claim 9 is preferably 5 parts by mass or more with respect to 100 parts by mass of the total amount of the high-melting paraffin wax and the higher alcohol, 95 parts by mass or less, more preferably 10 parts by mass or more and 90 parts by mass or less, and still more preferably 30 parts by mass or more and 85 parts by mass or less.

A heat storage material composition according to a tenth aspect of the invention further contains a low-melting-point paraffin wax having a melting point lower than that of the paraffin wax and the higher alcohol.
The low-melting-point paraffin wax is preferably a paraffin compound that is solid (solid) at room temperature, and more preferably has a melting point (phase transition point) of 35°C or higher and 55°C or lower, still more preferably 40°C or higher and 50°C or higher. ° C. or less, and the normal paraffin compound having an even number of carbon atoms, 2n (n is one number selected from natural numbers). The amount of the low melting point paraffin wax to be blended is preferably in the range of 3 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the total amount of the high melting point paraffin wax, the higher alcohol and the low melting point paraffin wax. It is compounded.

According to the heat storage material composition according to the invention of claim 1, the paraffin wax and the higher alcohol having a difference in melting point within the range of 20° C. or more and 40° C. or less are contained.
If the combination of paraffin wax and higher alcohol has a melting point difference of 20°C or more and 40°C or less, the heat storage function of the paraffin wax and the higher alcohol can be maintained even if they are mixed without being granulated by microencapsulation or the like. Each latent heat content of paraffin wax and higher alcohol is maintained without deactivation. That is, looking at the DSC curve measured by the differential scanning calorimetry method (DSC method), the endothermic peaks do not overlap and have a plurality of peaks, and the paraffin wax and the higher alcohol have different temperatures that are not continuous. The heat storage effect is demonstrated in multiple temperature ranges by changing the phase in each region. In particular, in the mixing of paraffin wax and higher alcohol, which have such a difference in melting point, the paraffin wax and the higher alcohol undergo phase changes in discontinuous different temperature ranges, so that the paraffin wax and the higher alcohol solidify as the temperature rises. Since the two phases of the liquid coexist, the heat transfer to the heat storage material on the high melting point side can also be favorably performed. Therefore, a high heat storage effect can be exhibited as a whole, the heat absorption and heat storage effect of the heat energy of the refrigerant for cooling the heat source and its surroundings are high, and the temperature rise of the refrigerant can be effectively suppressed.

According to the heat storage material composition of the invention of claim 1 , the melting point (phase transition point) of the paraffin wax is in the range of 65° C. or higher and 85° C. or lower, and is higher than the melting point of the higher alcohol. Therefore , for example , it is suitable for suppressing the temperature rise of a refrigerant whose upper limit temperature is set to around 100° C., and a high temperature rise suppressing effect can be exhibited for such a refrigerant.

According to the heat storage material composition according to the invention of claim 2 , since the main component of the paraffin wax is n-hexatriacontane (n-C ₃₆ H ₇₄ ), even if it is mixed with a higher alcohol, the solid phase It is chemically stable in both state and liquid phase, has a high latent heat capacity, and exhibits a high heat storage effect. Therefore, in addition to the effect described in claim 1 , for example, it is suitable for suppressing the temperature rise of a refrigerant whose upper limit temperature is set to around 100° C., and a high temperature rise suppressing effect can be stably obtained for such a refrigerant. be done.

According to the heat storage material composition according to the third aspect of the invention, since the higher alcohol is an aliphatic alcohol having 13 or more and 18 or less carbon atoms, it can be obtained at low cost and with high purity. Therefore, in addition to the effect described in claim 1 or claim 2 , a high temperature rise suppressing effect of the refrigerant can be stably obtained due to a stable high heat storage effect. More preferably, if the melting point is 35° C. or more and 60° C. or less, the phase change is unlikely to occur in a normal state without a heat load, and deterioration due to repeated phase changes, that is, a decrease in the latent heat amount, is unlikely to occur. Therefore, a long-term, stable effect of suppressing the temperature rise of the refrigerant can be obtained.

According to the heat storage material composition according to the invention of claim 4 , since the higher alcohol is 1-hexadecanol, even when mixed with the paraffin wax, it is chemically stable in both the solid phase state and the liquid phase state. It has a high latent heat capacity and exhibits a high heat storage effect. Therefore, in addition to the effect described in any one of claims 1 to 3 , a high refrigerant temperature rise suppressing effect can be obtained more stably. In addition, since the phase change is less likely to occur in a state where the heat load is small, deterioration due to repeated phase changes, that is, the latent heat amount is less likely to decrease, the effect of suppressing the temperature rise of the refrigerant can be obtained stably for a longer period of time.

According to the heat storage material composition according to the fifth aspect of the invention, the amount of the high-melting paraffin wax and the higher alcohol blended is 100 parts by mass of the high-melting-point heat storage material of the high-melting paraffin wax and the higher alcohol. On the other hand, the heat storage material on the low melting point side is preferably in the range of 80 to 550 parts by mass. Within this range, the coexistence balance of the liquid phase of the low-melting-point heat storage material and the solid phase of the high-melting-point heat-storage material accompanying temperature rise enables effective heat transfer to the high-melting-point heat storage material. In addition to the effect described in any one of claims 1 to 4 , it is possible to obtain a high effect of suppressing and mitigating the temperature rise of the refrigerant.
In particular, with respect to 100 parts by mass of the high melting point heat storage material, the low melting point side heat storage material is more preferably in the range of 100 to 500 parts by mass or less, still more preferably in the range of 300 to 500 parts by mass or less. If there is, it is possible to improve the effect of suppressing the temperature rise of the refrigerant more than when paraffin wax or higher alcohol is used alone.

According to the heat storage material composition according to the sixth aspect of the invention, when the total amount of the high melting point paraffin wax and the higher alcohol is 100 parts by mass, the higher melting point side of the high melting point paraffin wax and the higher alcohol can store heat. The material is preferably in the range of 10 to 60 parts by mass, and the heat storage material on the low melting point side is preferably in the range of 40 to 90 parts by mass. Within this range, the coexistence balance of the liquid phase of the low-melting-point heat storage material and the solid phase of the high-melting-point heat-storage material accompanying temperature rise enables effective heat transfer to the high-melting-point heat storage material. In addition to the effect described in any one of claims 1 to 5 , it is possible to obtain a higher effect of suppressing and mitigating the temperature rise of the refrigerant.
In particular, the heat storage material on the high melting point side is more preferably in the range of 10 to 55 parts by mass, still more preferably 10 to 30 parts by mass, per 100 parts by mass of the total amount of the high melting point paraffin wax and the higher alcohol. part, the heat storage material on the low melting point side is more preferably in the range of 45 to 90 parts by mass, more preferably in the range of 70 to 90 parts by mass, when paraffin wax or higher alcohol is used alone It is possible to improve the effect of suppressing the temperature rise of the refrigerant.

According to the heat storage material composition according to the invention of claim 7 , since it further contains a solid-solid phase transition type phase change material, the effect of any one of claims 1 to 6 In addition, the increase in volume change due to phase change can be relatively reduced.

According to the heat storage material composition of the eighth aspect of the invention, the solid-solid phase transition type phase change material is trimethylolethane (C ₅ H ₁₂ O ₃ ), so it is mixed with a higher alcohol and paraffin wax. Also, it is chemically stable, and deterioration due to repeated use, that is, a decrease in the amount of latent heat, does not readily occur. Therefore, in addition to the effect described in claim 7 , a stable heat storage effect can be exhibited by the solid-solid phase transition type phase change material. In addition, considering the solid phase transition point of trimethylolethane (C ₅ H ₁₂ O ₃ ), it is suitable for suppressing the temperature rise of a refrigerant whose upper limit temperature is set to around 100 ° C., and the effect of suppressing the temperature rise for such a refrigerant can also be improved.

According to the heat storage material composition of the ninth aspect of the invention, the solid-solid phase transition type phase change material is preferably 5 to 95 mass parts per 100 mass parts of the total amount of the paraffin wax and the higher alcohol. In addition to the effect described in claim 7 or claim 8 , it is possible to improve the effect of suppressing the temperature rise of the refrigerant.

According to the heat storage material composition of the invention of claim 10, since it further contains a low-melting paraffin wax having a melting point lower than that of the paraffin wax and the higher alcohol, any one of claims 1 to 9 . In addition to the effect described in one, a heat storage effect is obtained from the lower temperature side.

FIG. 1 is an explanatory diagram of an evaluation test apparatus for evaluating the effect of suppressing the temperature rise of the refrigerant by the heat storage material composition of the present embodiment. FIG. 2 is a graph of a DSC curve measured by differential scanning calorimetry (DSC method) for the heat storage material composition according to Example 1 of the present embodiment. FIG. 3 is a graph of a DSC curve measured by differential scanning calorimetry (DSC method) for the heat storage material composition according to Example 2 of the present embodiment. FIG. 4 is a graph of a DSC curve measured by differential scanning calorimetry (DSC method) for the heat storage material composition according to Example 3 of the present embodiment. FIG. 5 is a graph of a DSC curve measured by differential scanning calorimetry (DSC method) for the heat storage material composition according to Example 4 of the present embodiment. FIG. 6 is a graph of a DSC curve measured by differential scanning calorimetry (DSC method) for the heat storage material composition according to Example 5 of the present embodiment. FIG. 7 is a graph of a DSC curve measured by differential scanning calorimetry (DSC method) for the heat storage material composition according to Example 6 of the present embodiment. 8 is a graph of a DSC curve measured by differential scanning calorimetry (DSC method) for the phase change material of Reference Example 1. FIG. 9 is a graph of a DSC curve measured by differential scanning calorimetry (DSC method) for the phase change material of Reference Example 2. FIG. 10 is a graph of a DSC curve measured by differential scanning calorimetry (DSC method) for the phase change material of Reference Example 3. FIG. 11 is a graph of a DSC curve measured by differential scanning calorimetry (DSC method) for the phase change material of Reference Example 4. FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the embodiment, the numerical values shown in the same column of Table 1 indicate the magnitude of the quantity, and since there is basically no difference in the materials, redundant description will be omitted here.

The inventors of the present invention have found that the cooling system for cooling heat sources such as motors, fuel cells, batteries, etc., can be effectively cooled even during temporary high heat generation such as during high load and rapid charging without enlarging the cooling system. In order to make this possible, we came up with the idea of absorbing and storing the heat of the refrigerant used in the cooling system that cools the heat source in a heat storage material. As a result, it was found that a mixture of paraffin wax and higher alcohol with a melting point difference of 20°C or more and 40°C or less was able to absorb and store the heat of the refrigerant, resulting in a rapid rise of the refrigerant even when the heat source generated a large amount of heat. It was found that the temperature can be suppressed and alleviated.

That is, in the combination of paraffin wax and higher alcohol, which have different melting points of 20° C. or higher and 40° C. or lower, the paraffin wax or higher alcohol need not be granulated by sealing the paraffin wax or higher alcohol in microcapsules, but simply mixing these materials. A high heat absorption and heat storage effect was obtained, and a high refrigerant temperature rise suppression effect was obtained.

The reason for this is not necessarily clear, but in a combination of paraffin wax and higher alcohol with a melting point difference of 20° C. or higher and 40° C. or lower, the heat storage performance of paraffin wax and higher alcohol is not deactivated, and the paraffin wax does not lose its heat storage performance. It can be inferred that the high latent heat inherent to each of the paraffin wax and the higher alcohol was maintained without heat storage dispersion, loss, etc., even when mixed with the higher alcohol. That is, when looking at the DSC curve obtained by differential scanning calorimetry (DSC method) for a mixture of paraffin wax and higher alcohol having a predetermined melting point difference, a broad single endothermic (melting) peak (peak is Since the DSC curve has multiple endothermic peaks (double peaks) instead of overlapping and broad curves), heat storage dispersion, loss, etc. are difficult to occur, and the high heat storage capacity inherent in paraffin wax and higher alcohol. It is presumed that the high heat storage effect was able to be exhibited by making full use of Furthermore, in the combination of paraffin wax and higher alcohol with a melting point difference of 20° C. or more and 40° C. or less, when the temperature is raised, the solid phase (solid, powder) of the heat storage material on the high melting point side and the liquid phase of the heat storage material on the low melting point side A state of coexistence of multiple (liquid) phases occurs, and with such a balance of multiple phases, heat is well transferred to the heat storage material, heat storage loss is less likely to occur, and the effect of suppressing the temperature rise of the refrigerant is high. It can be guessed.

In the combination of paraffin wax and higher alcohol with a melting point difference of 20° C. or higher and 40° C. or lower, two phase transition points corresponding to the phase changes near the respective inherent melting points of paraffin wax and higher alcohol are obtained. (phase transition temperature), the DSC curve has melting peaks (double peaks) in a plurality of different temperature ranges, and the paraffin wax and the higher alcohol undergo phase changes in different (discontinuous) temperature ranges separated from each other. It stores and absorbs heat. That is, compared to a material having a melting peak in a single temperature range, the heat absorption and heat storage effects are not limited to a specific temperature range, and the heat storage effect is exhibited in a plurality of temperature ranges. Therefore, the heat storage material having a low melting point provides a heat storage effect even when the temperature rises in a low temperature zone, so that the refrigerant can be maintained at a low temperature, so that the heat load on the heat source and its surroundings can be reduced. Furthermore, even with a sudden increase in heat energy due to a sudden temperature rise of the heat source, the stepwise heat storage characteristic from the low temperature side to the high temperature side prevents the heat storage capacity from immediately exceeding the limit and the temperature of the refrigerant rises. effective in suppression.

Thus, the heat storage material composition according to the embodiment of the present invention contains paraffin wax and higher alcohol as essential components, and the melting point difference between them is 20°C or more and 40°C or less, preferably 22°C or more and 35°C. Below, more preferably, the temperature is 24° C. or higher and 30° C. or lower.

Particularly preferred is a combination of paraffin wax having a melting point of 65° C. or higher and 85° C. or lower and higher alcohol having 13 or more and 18 or less carbon atoms. With this combination, it is possible to stably obtain high heat storage properties in the desired temperature range at low cost. That is, both paraffin waxes with a melting point of 65° C. or higher and 85° C. or lower and higher alcohols with a carbon number of 13 or higher and 18 or lower can be obtained at low cost and with high purity, so that there is little variation in melting behavior. As a result, a stable phase transition temperature and a high latent heat amount can be obtained, and a high temperature rise suppressing effect can be stably obtained.

Examples of paraffin waxes having a melting point of 65° C. or higher and 85° C. or lower include triacontane (C ₃₀ H ₆₂ ), hentriacontane (C ₃₁ H ₆₄ ), dotriacontane (C ₃₂ H ₆₆ ), tritriacontane ( C ₃₃ H ₆₈ ), tetratriacontane (C ₃₄ H ₇₀ ), pentatriacontane (C ₃₅ H ₇₂ ), hexatriacontane (C ₃₆ H ₇₄ ), heptatriacontane (C ₃₇ H ₇₆ ), octatriacontane ( C ₃₈ H ₇₈ ), nonatriacontane (C ₃₉ H ₈₀ ), tetracontane (C ₄₀ H ₈₂ ), hentetracontane (C ₄₁ H ₈₄ ) and the like.

In addition, as the higher alcohol having 13 or more and 18 or less carbon atoms, considering the price and availability, etc., it is a monohydric alcohol and is generally a straight-chain primary alcohol. may be For example, tridecyl alcohol (tridecanol), myristyl alcohol (1-tetradecanol), pentadecyl alcohol (1-pentadecanol), cetanol (1-hexadecanol), 1-heptadecanol, stearyl alcohol (1- octadecanol), isostearyl alcohol and other saturated higher alcohols can be used.

Here, in the cooling system (air-cooled, oil-cooled, water-cooled, etc.) of heat sources such as motors, fuel cells, batteries, etc., the cooling system is designed with the limit of control at around 100 ° C. Therefore, with a margin, for example, when 90 ° C. to 95 ° C. is assumed to be the temperature rise limit temperature of the refrigerant, the temperature design of the heat storage material composition that is effective in suppressing the temperature rise of the refrigerant is preferably: A paraffin wax having a melting point of 65° C. or higher and 85° C. or lower, more preferably 70° C. or higher and 80° C. or lower, and a carbon number of preferably 13 or higher and 18 or lower, more preferably 14 or higher and 17 or lower. Preferably, it is a combination of higher alcohols having a melting point of 35° C. or higher and 60° C. or lower, more preferably 40° C. or higher and 55° C. or lower. More preferably, a paraffin wax based on hexatriacontane (C ₃₆ H ₇₄ ) with a melting point in the range of about 75°C to 79°C and a carbon wax with a melting point in the range of about 49°C to 52°C. It is a combination of 1-hexadecanol (also called cetanol, cetyl alcohol, and pamityl alcohol), which is a primary alcohol of number 16 and a higher saturated fatty alcohol.

In their combination, even when mixed with each other, the heat storage performance of each is not deactivated or deteriorated, and each inherent high latent heat is maintained, and furthermore, the solid phase (solid, powder) and liquid phase ( Due to the ease of heat transfer to the heat storage material due to the favorable coexistence balance of multiple phases (liquid), it is possible to increase the effect of alleviating the temperature rise rate until the refrigerant reaches 90°C to 95°C. In addition, even after repeated use, the effect of suppressing the temperature rise of the refrigerant does not deteriorate, and a high effect of suppressing the temperature rise of the refrigerant can be stably obtained for a long period of time.

The mixing ratio of the paraffin wax and the higher alcohol having a predetermined melting point difference is not particularly limited, but preferably, when the high melting point side heat storage material of the paraffin wax and the higher alcohol is 100 parts by mass, the paraffin wax and the higher alcohol are mixed. 80 parts by mass or more and 500 parts by mass or less, more preferably 100 parts by mass or more and 500 parts by mass or less, still more preferably 300 parts by mass or more and 500 parts by mass of the heat storage material on the low melting point side of the higher alcohol It is considered to be within the following range.
In addition, for a total amount of 100 parts by mass of paraffin wax and higher alcohol, the amount of the heat storage material on the high melting point side is preferably 10 parts by mass or more and 60 parts by mass or less, more preferably 10 parts by mass. In the range of 10 parts by mass or more and 55 parts by mass or less, more preferably 10 parts by mass or more and 30 parts by mass or less. It is preferably in the range of 45 parts by mass or more and 90 parts by mass or less, and more preferably in the range of 70 parts by mass or more and 90 parts by mass or less.
This combination enables effective heat transfer to the heat storage material due to the coexistence balance between the liquid phase of the heat storage material on the low melting point side and the solid phase of the heat storage material on the high melting point side as the temperature rises, suppressing the temperature rise of the refrigerant, A high relaxation effect can be obtained.

Furthermore, in the heat storage material composition according to the present embodiment, in addition to paraffin wax and higher alcohol having a melting point difference of 20° C. or more and 40° C. or less, other latent heat storage materials (phase change materials, phase change materials) are added. Mixtures are also possible, preferably the use of latent heat storage materials that change phase above or below the intrinsic melting point of the paraffin wax and the intrinsic melting point of the higher alcohol.

More preferably, when a latent heat storage material having a phase change point (phase change temperature) higher than the intrinsic melting points of paraffin wax and higher alcohol is mixed, the paraffin wax or higher alcohol having the higher melting point is Different types of latent heat storage materials are mixed. In addition, when mixing a latent heat storage material having a phase change point (phase change temperature) lower than the intrinsic melting point of each of paraffin wax and higher alcohol, it is necessary to mix a latent heat storage material different from the low melting point paraffin wax or higher alcohol. Mix the latent heat storage material. As a result, even when other latent heat storage materials are mixed, the latent heat storage materials are less likely to be compatible with paraffin waxes and higher alcohols having a phase change point difference of 20° C. or more and 40° C. or less, and the heat storage amount of each component is reduced. is suppressed. In addition, heat storage over a wider temperature range will broaden the range of applications for refrigerants. Furthermore, it is possible to improve the heat transfer to the heat storage material by the coexistence balance of a plurality of phases (solid phase, liquid phase), thereby suppressing the temperature rise of the refrigerant and improving the mitigation effect.

As an example of a latent heat storage material (phase change material, phase change material) different from paraffin wax and higher alcohol having a melting point difference of 20° C. or more and 40° C. or less, solid-solid phase change type phase change material (hereinafter referred to as simply a solid-to-solid phase transition material) can be used. Heat storage by the solid-solid phase transition material is heat storage based on the phase transition between solid phases, that is, heat storage due to latent heat when changing from the solid phase to the solid phase, and since it is a first-order phase transition, almost no volume change occurs. No. For this reason, by reducing the amount of paraffin wax and higher alcohol compounded and adding a solid-solid phase transition material, and also storing heat in it, the paraffin wax and higher alcohol will leak out when the phase changes from the solid phase to the liquid phase. It can reduce concerns such as bleeding and seepage.

Examples of the solid-solid phase transition material used in the heat storage material composition according to the present embodiment include polyhydric alcohols such as trimethylolethane, pentaerythritol, and neopentyl glycol, and metal oxides such as vanadium and barium (oxidized Vanadium, titanium oxide, barium oxide, etc.) and vanadium sulfide can be used. Preferred is trimethylolethane (CH ₃ C(CH ₂ OH) ₃ ). In particular, when trimethylolethane is mixed with a predetermined paraffin wax and a higher alcohol, for example, it exhibits heat storage and heat absorption characteristics that are effective in suppressing the temperature rise of the refrigerant until it reaches 90 ° C. to 95 ° C. It is possible to suppress the temperature rise of the refrigerant and improve the mitigation effect. That is, since the prescribed paraffin wax and the higher alcohol undergo a phase transition due to the temperature rise, heat is well transferred to the solid trimethylolethane, and heat storage due to the solid-solid phase transition of the trimethylol is effectively exhibited, and the refrigerant is cooled. It enables suppression of temperature rise and improvement of mitigation effect.

Such a solid-solid phase transition material is preferably 5 parts by mass or more and 95 parts by mass or less, more preferably 10 parts by mass or more and 90 parts by mass, per 100 parts by mass of the total amount of the higher alcohol and the high-melting paraffin wax. It is blended in the range of not more than 30 parts by mass and not more than 85 parts by mass, more preferably not less than 30 parts by mass. The total amount of the heat storage material, that is, the total amount of the solid-solid phase transition material, the higher alcohol, and the paraffin wax (including the high melting point paraffin wax and the low melting point paraffin wax described below when blended) is 100 parts by mass. For, the solid-solid phase transition material is preferably 3 parts by mass or more and 50 parts by mass or less, more preferably 4 parts by mass or more and 48 parts by mass or less, still more preferably 5 parts by mass or more and 45 It is a blend within the range of parts by mass or less.
This combination enables effective heat transfer to the heat storage material due to the coexistence balance of the liquid phase and the solid phase accompanying the temperature rise, and makes it possible to suppress the temperature rise of the refrigerant and improve the mitigation effect.

Further, as other latent heat storage materials (phase change materials, phase transition materials), solid-liquid phase transition type paraffins, higher alcohols, which are different from paraffin waxes and higher alcohols having a melting point difference of 20° C. or more and 40° C. or less, A higher fatty acid (fatty acid ester) or the like can also be mixed.
As a combination of paraffin wax and higher alcohol having a melting point difference of 20° C. or more and 40° C. or less, for example, a high melting point paraffin wax having a melting point of 65° C. or more and 85° C. or less and a higher alcohol having 13 or more and 18 or less carbon atoms. is further blended with a low-melting-point paraffin wax having a lower melting point than those paraffin waxes and higher alcohols, thereby enabling heat storage and heat absorption from a lower temperature side. In order to distinguish from low-melting paraffin wax in comparison, paraffin wax having a melting point higher than that of low-melting paraffin wax may be referred to as high-melting paraffin wax for convenience.

The low melting point paraffin wax at this time has a melting point lower than that of the high melting point paraffin wax by 20° C. or more, and such a low melting point paraffin wax does not overlap the endothermic peak (melting peak) of the high melting point paraffin wax. It also does not lower the latent heat of the high-melting paraffin wax. In particular, when the phase transition starts on the lower temperature side, the heat transfer to the high melting point component side improves, and the heat absorption and heat storage function effectively, suppressing the temperature rise of the refrigerant and improving the mitigation effect. It becomes possible. Furthermore, since such low-melting paraffin waxes are available at relatively low prices, cost reduction is also possible. And even if the cost is reduced by blending low-melting paraffin, the effect of suppressing the temperature rise of the refrigerant and mitigating it can be enhanced.

Examples of such low-melting paraffin wax include n-hexadecane (C ₁₆ H ₃₄ ), n-heptadecane (C ₁₇ H ₃₆ ), n-octadecane (C ₁₈ H ₃₈ ), n-nonadecane (C ₁₉ H ₄₀ ), n-icosane (C ₂₀ H ₄₂ ), n-henicosane (C ₂₁ H ₄₄ ), n-docosane (C ₂₂ H ₄₆ ), n-tricosane (C ₂₃ H ₄₈ ), n-tetracosane (C ₂₄ H ₅₀ ) can be used, but from the viewpoint of high latent heat and low cost, those containing normal _paraffin with an even number of carbon _atoms as the main component are preferred. Preferred are n-docosane (C ₂₂ H ₄₆ ) and n-tetracosane (C ₂₄ H ₅₀ ).

The amount of the low melting point paraffin wax is preferably 5 parts by mass or more and 95 parts by mass or less, more preferably 5 parts by mass or more and 90 parts by mass, based on 100 parts by mass of the total amount of the higher alcohol and the high melting point paraffin wax. More preferably, it is blended in the range of 7 parts by mass or more to 85 parts by mass.
The total amount of the latent heat storage material is preferably 3 parts by mass or more and 50 parts by mass or less, more preferably 4 parts by mass or more and 45 parts by mass or less, and still more preferably 5 parts by mass or more. , 40 parts by mass or less. That is, when the latent heat storage material to be used is only high-melting paraffin wax, higher alcohol and low-melting paraffin wax, the total amount of high-melting paraffin wax, higher alcohol and low-melting paraffin wax is preferably is in the range of 3 to 50 parts by mass, more preferably 4 to 45 parts by mass, still more preferably 5 to 40 parts by mass. When the latent heat storage material to be used is high-melting paraffin wax, higher alcohol, solid-solid phase transition material and low-melting paraffin wax, high-melting paraffin wax, higher alcohol solid-solid phase transition material and low-melting paraffin wax The total amount is preferably 3 to 55 parts by mass, more preferably 4 to 50 parts by mass, and still more preferably 5 to 45 parts by mass, relative to 100 parts by mass.
This combination enables effective heat transfer to the heat storage material due to the coexistence balance of the liquid phase and the solid phase accompanying the temperature rise, and makes it possible to suppress the temperature rise of the refrigerant and improve the mitigation effect.

The heat storage material composition according to the embodiment of the present invention contains, as essential components, a higher alcohol having a melting point difference of 20° C. to 40° C. and paraffin wax. In combination with paraffin wax, when looking at the DSC curve by differential scanning calorimetry (DSC method), the endothermic peak (melting peak) does not become a single wide endothermic peak, It has multiple endothermic peaks (double peaks) near the melting point inherent to alcohol.
That is, even if the higher alcohol and the paraffin wax are mixed without being granulated by microencapsulation or the like, the heat storage function of the alcohol and the paraffin wax is not deactivated, and the amount of latent heat originally possessed by the paraffin wax and the higher alcohol is maintained. , a high heat storage capacity is obtained as a whole.

In other words, the phase transition accompanying the temperature rise occurs in separate and different temperature zones for paraffin wax and higher alcohol, and even when compared with the latent heat measured for only paraffin wax or only higher alcohol, the total heat storage amount The high latent heat of the paraffin wax and the higher alcohol is maintained without a significant decrease in the . Furthermore, it is a stepwise heat absorption and heat storage in a plurality of temperature ranges corresponding to the phase transition of each of the higher alcohol and the paraffin wax. A state in which a plurality of different phases, such as a liquid phase of wax and a solid phase of higher alcohol, coexist with the two components of alcohol and paraffin wax occurs. For this reason, heat can be conducted well to the heat storage material on the high melting point side, heat storage loss is less likely to occur, and the effect of suppressing and mitigating the temperature rise of the refrigerant can be enhanced.

In the case where the endothermic peak (melting peak) overlaps and becomes a single wide endothermic peak, the large temperature difference before and after the phase change makes it easy for heat storage loss and heat storage dispersion to occur, but the melting point difference is large. In the combination of higher alcohol and paraffin wax within the range of 20°C to 40°C, the heat storage performance is not deactivated due to a chemical reaction between the components, and the paraffin wax and the higher alcohol are separated in discontinuous different temperature ranges. Since the phase transition occurs and the endothermic peak in a narrow range is dispersed, heat storage loss, heat storage dispersion, etc. are small, and it is thought that the inherent latent heat of the paraffin wax and the higher alcohol is maintained.

Thus, according to the heat storage material composition of the present embodiment, even when a plurality of latent heat storage materials are combined, a plurality of phase transitions between the vicinity of the intrinsic melting point of paraffin wax and the vicinity of the intrinsic melting point of higher alcohol can be achieved. It has points and stores heat in a plurality of steps in different temperature ranges, and a high heat storage effect can be obtained without deactivating the heat storage function even without granulation such as microencapsulation.

Therefore, for example, the heat storage material composition of the present embodiment is enclosed in a container, bag, or the like made of metal or synthetic resin (eg, polyvinyl chloride, polyethylene, polypropylene, polystyrene, polyamide, nylon, polyester, polyethylene terephthalate). , is provided in contact with the coolant in the cooling circuit for cooling the heat source such as the motor, the battery of the secondary battery, the fuel cell, etc., the heat energy added to the coolant from the heat source is A large amount of heat can be absorbed and stored in the heat storage material composition, and the temperature rise of the refrigerant can be effectively suppressed to enable high temperature control.

When the heat storage material composition of the present embodiment is filled into a flexible container or bag, if the prescribed paraffin wax and higher alcohol are solid at room temperature, solid paraffin wax and higher alcohol are prepared in advance. Is preferably melted by heating and then mixed, or melted in a mixed state and naturally cooled to fill the solid mixture, but each solid material may be directly filled into a container or bag. Alternatively, each solid material may be uniformly mixed and then filled into a container or a bag. When a solid-solid phase change material is blended, it is mixed with paraffin wax and higher alcohol without being melted.

According to the heat storage material composition of the present embodiment, the higher alcohol and paraffin wax having a melting point difference in the range of 20° C. to 40° C. are mixed or combined. It has multiple endothermic peaks (melting peaks) near the melting point of higher alcohols and near the melting point inherent to higher alcohols, and phase changes occur in multiple different temperature zones to absorb and store heat. Compared to using only the material or having a single endothermic peak, it has high versatility that can handle a wide range of temperature design of the cooling circuit that cools the heat source, and does not rise to high temperatures during use. Even in this state, a predetermined heat storage effect is exhibited, and the heat load on the heat source and its surroundings can be reduced.

That is, when only a single latent heat storage material is used, the effect of heat storage is limited to the vicinity of its inherent melting point. Since heat can be stored in a plurality of temperature ranges with a temperature difference of about 20 to 40° C. between endothermic peaks near and near the melting point of paraffin wax, the heat storage effect can be obtained in a wide range of temperature ranges. Therefore, it is possible to store heat in a desired temperature range corresponding to the design temperature of the refrigerant using the heat absorption of the heat storage material composition, that is, to facilitate control of the desired heat storage temperature. Temperature rise can be suppressed. Therefore, the heat storage characteristic can be set to be effective in suppressing the temperature rise of various refrigerants designed to have different temperatures according to the type of heat source, the surrounding structure, etc., and can be used for a wide range of heat storage applications.

In particular, when only one type of latent heat storage material with a relatively low melting point is used, when the temperature of the heat source suddenly rises, a large amount of heat energy is suddenly added to the refrigerant, and the heat storage capacity is quickly increased. When the limit is exceeded and the heat storage capacity is exceeded, the temperature of the refrigerant rises again at a rapid rate, so there is a fear that the effective temperature rise suppression effect of the refrigerant cannot be obtained. On the other hand, if only one type of latent heat storage material with a relatively high melting point is used, the temperature of the refrigerant rises to a high temperature before heat is stored, increasing the heat load on the heat source and its surroundings.
On the other hand, in the heat storage material composition of the present embodiment, in which the higher alcohol and the paraffin wax having a predetermined melting point difference are combined, there is a difference in melting temperature between the higher alcohol and the paraffin wax. Since the heat can be stored in a large space, even when the heat energy applied to the refrigerant increases rapidly due to the sudden high heat generation of the heat source, the temperature rise rate of the refrigerant can be moderated, and the rapid temperature rise of the refrigerant can be suppressed. As a result, the cooling effect of the coolant can be enhanced, and the time required for the coolant to reach the limit temperature can be extended. Moreover, since the heat storage effect can be obtained even at low temperatures, the cooling temperature can be maintained at a low temperature even when the load is small, thereby reducing the heat load on the heat source and its surroundings.

Paraffin waxes and higher alcohols have a relatively large amount of latent heat (amount of heat of fusion) among heat storage materials, and a large amount of heat storage per unit volume. It is excellent in heat dissipation repeatability, is hard to be deteriorated, and can obtain a stable heat storage amount and heat storage effect for a long period of time.
In particular, since paraffin waxes and higher alcohols have low compatibility, heat storage is stable for a long period of time without causing a decrease in the amount of heat storage due to reactions or mutual dissolution of the components even after repeated use, or a shift in the phase transition point. As a result, it is possible to obtain the effect of suppressing the temperature rise of the refrigerant.
In addition, since it is readily available and inexpensive, and high heat storage performance can be obtained without granulation such as microencapsulation, the cost can be reduced. In addition, since it is hard to corrode, even if it is enclosed in a container made of metal, synthetic resin, or the like and placed in contact with the refrigerant, it will not deteriorate. Further, since the heat storage density is high, particularly, as described above, the combination of paraffin wax and higher alcohol can provide a high latent heat amount as a whole, so miniaturization is also possible.

Here, for heat sources such as motors, batteries, and fuel cells, the limit set temperature of the coolant for cooling them is set to, for example, around 100°C. Assuming that the heat storage material composition of the present embodiment is used, preferably, the heat storage material composition of the present embodiment is composed of a high-melting paraffin wax having a melting point of 65° C. or higher and 85° C. or lower and a carbon number is 13 or more and 18 or less higher alcohol. More preferably, it further contains a solid-solid phase change material and/or a paraffin wax having a predetermined melting point difference and a low melting point paraffin wax having a melting point lower than that of a higher alcohol.

Thus, if a combination of a high-melting paraffin wax having a melting point of 65° C. or higher and 85° C. or lower and a higher alcohol having a carbon number of 13 or higher and 18 or lower having a lower melting point of 20° C. to 40° C. or lower, for example, For refrigerants with a temperature rise limit temperature of 90°C to 95°C, the heat absorption and heat storage effects are exhibited in stages from the low temperature side to the high temperature side, so heat is added to the refrigerant due to the sudden high heat generation of the heat source. Even when the energy increases rapidly, the temperature rise rate of the refrigerant can be slowed down, and the rapid temperature rise of the refrigerant can be effectively suppressed, thereby suppressing the decrease in cooling efficiency. Moreover, even when the temperature does not reach a predetermined high temperature, that is, even when the load is small, the heat absorption and heat storage effects can be obtained, so the heat load on the heat source and its surroundings can be reduced.

Furthermore, when a solid-solid phase change material is blended, the volume change due to phase change can be relatively reduced, and the solid-liquid phase change material such as paraffin wax or higher alcohol exudes when melted. can be reduced. Therefore, it is possible to save space by reducing and simplifying the capacity of the container or bag, and to increase the degree of freedom in installation. In addition, the solid-solid phase change material stores and absorbs heat during a phase change between solid phases, which is different from the heat storage due to the solid-liquid phase change of paraffin wax and higher alcohol, and the coexistence of the liquid phase and the solid phase. Effective heat transfer to the heat storage component due to the balance makes it possible to enhance the effect of suppressing the temperature rise of the refrigerant.

In addition, the cost can be reduced by blending a higher alcohol having a predetermined melting point difference and a low-melting paraffin wax having a lower melting point than the paraffin wax. Furthermore, by starting the phase change at a lower temperature side, the compatibility of the higher alcohol and paraffin wax is improved, the balance between the liquid phase and the solid phase is improved, and effective heat transfer to the heat storage component is achieved. As a result, it becomes possible to enhance the effect of suppressing the temperature rise of the refrigerant.

In this way, by using the heat storage material composition of the present embodiment for the refrigerant, the heat source becomes high temperature at the time of high load such as motor, battery, fuel cell, etc., at the time of rapid charging, etc., and the amount of heat energy in the refrigerant becomes Even when a large amount of heat is applied, the temperature rise of the refrigerant can be suppressed and mitigated by absorbing and storing the heat energy in the heat storage material composition. Therefore, even when the heat source generates a large amount of heat, it is possible to suppress a decrease in the cooling effect of the coolant that cools the heat source, and it is possible to maintain a high cooling effect.

In particular, the heat energy added to the refrigerant is absorbed and stored in the heat storage material composition, which suppresses and mitigates the temperature rise of the refrigerant. is not set at a low temperature, the cooling effect can be maintained without enlarging the cooling system and without increasing power consumption, and the cost can be reduced. In addition, in the case of such a heat storage material composition, a space-saving arrangement is provided in which a container or the like enclosing the heat storage material composition is provided so as to be in contact with the refrigerant flowing in the internal space of the cooling circuit for cooling the heat source. Therefore, it is possible to use the cooling system as it is without enlarging or modifying it, and to enhance the cooling sustainability and cooling effect.

Next, examples of the heat storage material composition according to the embodiment of the present invention will be specifically described.
As examples of the heat storage material composition according to the present embodiment, heat storage material compositions according to Examples 1 to 6 were produced with the formulation shown in Table 1.

In Examples 1 to 6, paraffin wax “HNP-51” manufactured by Nippon Seiro Co., Ltd. (melting point: 77° C., main component: hexatriacontane (n-(C ₃₆ H ₇₄ ) ) was used, and as a higher alcohol, "1-hexadecanol" (melting point: 49.0 ° C. to 51.5 ° C.) manufactured by Tokyo Chemical Industry Co., Ltd. was used.Further, Example 4 to Example In 6, "Parafol (registered trademark) 22-95" manufactured by Sasol Chemicals Japan Co., Ltd. (melting point: 42°C, main component: docosane (n-(C ₂₂ H ₄₆ ))) is used as the low-melting paraffin wax. As a solid-solid phase change material, "Trimethylolethane" (solid phase transition point: 89° C.) manufactured by Tokyo Chemical Industry Co., Ltd. was used.

In Examples 1 to 3, first, a high melting point paraffin wax whose main component is hexatriacontane and which is solid at room temperature and 1-hexadecanol as a higher alcohol which is solid at room temperature are placed in predetermined containers. and melted in a water bath or oil bath at 95°C.
Then, the molten high-melting paraffin wax and the molten 1-hexadecanol are blended in a container at a predetermined weight ratio, stirred and mixed in a water bath or oil bath at 95 ° C., and naturally cooled to normal temperature (room temperature). Each heat storage material composition according to Examples 1 to 3 was prepared by cooling.

Here, as shown in Table 1, in Example 1, 17 parts by mass of high-melting paraffin wax containing hexatriacontane as the main component and 1-hexadecanol as a higher alcohol were used in terms of the weight ratio of the solid content. The composition was 83 parts by mass. In the formulation of Example 1, 1-hexadecanol as a higher alcohol is 488 parts by mass for 100 parts by mass of high-melting paraffin wax.
In Example 2, 1-hexadecanol as a higher alcohol is reduced than in Example 1, and the high-melting paraffin wax whose main component is hexatriacontane is increased by that amount, and the weight ratio of solids is high. 33 parts by mass of melting point paraffin wax and 67 parts by mass of 1-hexadecanol as a higher alcohol were blended. In the composition of Example 2, 1-hexadecanol as a higher alcohol is 203 parts by mass for 100 parts by mass of high-melting paraffin wax.
In Example 3, 1-hexadecanol as a higher alcohol was further reduced than in Example 2, and the high melting point paraffin wax whose main component was hexatriacontane was further increased by that amount, and the weight ratio of the solid content was , 50 parts by mass of high-melting paraffin wax, and 50 parts by mass of 1-hexadecanol as a higher alcohol. In the formulation of Example 3, 1-hexadecanol as a higher alcohol is 100 parts by mass for 100 parts by mass of high-melting paraffin wax.

Furthermore, in Examples 4 to 6, high-melting paraffin wax (melting point: 77°C) whose main component is hexatriacontane and 1-hexadecanol (melting point: 49.0°C to 51.5°C) as a higher alcohol ° C), a low-melting paraffin wax (melting point: 42 ° C) whose main component is docosane, and trimethylolethane (solid phase transition point: 89 ° C) as a solid-solid phase change material are blended. Each heat storage material composition according to Examples 4 to 6 was obtained.
Specifically, in Examples 4 to 6, first, a high-melting paraffin wax whose main component is hexatriacontane, which is solid at room temperature, and 1-hexadecanol as a higher alcohol, which is solid at room temperature and a low-melting-point paraffin wax whose main component is docosane, which is solid at room temperature, were placed in a container and melted in a water bath or an oil bath at 95°C.
Then, the melted high-melting paraffin wax, the melted 1-hexadecanol, the melted low-melting paraffin wax, and trimethylolethane, which is solid at room temperature, were mixed in a predetermined weight ratio in a container, and heated to 95°C. Each heat storage material composition according to Examples 4 to 6 was prepared by stirring and mixing in a hot water bath or an oil bath and naturally cooling to normal temperature (room temperature).

Here, as shown in Table 1, in Example 4, 25 parts by mass of high-melting paraffin wax containing hexatriacontane as the main component and 1-hexadecanol as a higher alcohol were used in terms of the weight ratio of the solid content. 45 parts by mass, 5 parts by mass of low-melting paraffin wax whose main component is docosane, and 25 parts by mass of trimethylolethane as a solid-solid phase change material. In the formulation of Example 4, 1-hexadecanol as a higher alcohol is 180 parts by mass for 100 parts by mass of high-melting paraffin wax. Further, the total amount of high-melting paraffin wax and 1-hexadecanol as a higher alcohol is 100 parts by mass, low-melting paraffin is 7.1 parts by mass, and trimethylolethane is used as a solid-solid phase change material. is 35.7 parts by mass.

In Example 5, in terms of the weight ratio of the solid content, 6 parts by mass of high-melting paraffin wax whose main component is hexatriacontane, 31 parts by mass of 1-hexadecanol as a higher alcohol, and low wax whose main component is docosane. 31 parts by mass of melting point paraffin wax and 31 parts by mass of trimethylolethane as a solid-solid phase change material were blended. In the formulation of Example 5, 1-hexadecanol as a higher alcohol is 517 parts by mass for 100 parts by mass of high-melting paraffin wax. Further, the total amount of high-melting paraffin wax and 1-hexadecanol as a higher alcohol is 100 parts by mass, 83.8 parts by mass of low-melting paraffin, and trimethylolethane as a solid-solid phase change material is 83.8 parts by mass.

In Example 6, in terms of the weight ratio of the solid content, 25 parts by mass of high-melting paraffin wax whose main component is hexatriacontane, 25 parts by mass of 1-hexadecanol as a higher alcohol, and 25 parts by mass of 1-hexadecanol as its main component. 45 parts by mass of melting point paraffin wax and 5 parts by mass of trimethylolethane as a solid-solid phase transition type phase change material were blended. In the formulation of Example 6, 1-hexadecanol as a higher alcohol is 100 parts by mass for 100 parts by mass of high-melting paraffin wax. Further, the total amount of high-melting paraffin wax and 1-hexadecanol as a higher alcohol is 100 parts by mass, 90 parts by mass of low-melting paraffin, and 10 parts by mass of trimethylolethane as a solid-solid phase change material. Department.

Further, as Reference Example 1, a high melting point paraffin wax whose main component is hexatriacontane and is solid at room temperature is placed in a container, melted in a water bath or oil bath at 95 ° C., and naturally cooled to room temperature (room temperature). Thus, a high-melting paraffin wax according to Reference Example 1 shown in Table 1 was prepared.
As Reference Example 2, 1-hexadecanol as a higher alcohol was placed in a container and melted in a hot water bath or oil bath at 95 ° C., and naturally cooled to normal temperature (room temperature). 1-hexadecanol was prepared as such a higher alcohol.
As Reference Example 3, a low-melting paraffin wax whose main component is docosane was placed in a container and melted in a hot water bath or an oil bath at 95° C., followed by natural cooling to normal temperature (room temperature). A low-melting paraffin wax was prepared according to
In Reference Example 4, only trimethylolethane was used as the solid-solid phase transition type phase change material.
The materials used in Reference Examples 1-4 are the same as the materials used in Examples 1-6.

Here, the differential scanning calorimetry of the heat storage material compositions according to Examples 1 to 6 was measured. Graphs of DSC curves of the measurement results are shown in FIGS. As shown in the DSC curves of FIGS. 2 to 7, according to the heat storage material compositions of Examples 1 to 6, the endothermic (melting) peak (about 70° C. to 90° C.) based on the phase change of the high-melting paraffin wax ° C.) and an endothermic peak (within a range of about 40° C. to 50° C.) based on the phase change of 1-hexadecanol as a higher alcohol, and these endothermic peaks do not overlap each other ( exist independently without multiple peaks). That is, there are two or more independent endothermic (melting) peaks that have a plurality of different phase transition points (phase transition temperatures) without overlapping, and the low temperature side of 50 ° C. or lower and the high temperature side of 70 ° C. or higher are present. It can be seen that heat absorption and heat storage occur in multiple temperature zones.
In addition, in the heat storage material compositions of Examples 4 to 6, in which the low-melting paraffin and trimethylolethane as a solid-solid phase change material were further blended, the DSC curve graphs shown in FIGS. The endothermic peak due to the phase change of low-melting paraffin or the endothermic peak due to the phase change of trimethylolethane overlaps with the endothermic peak of high-melting paraffin wax or the endothermic peak of 1-hexadecanol or is single without overlapping. exists as a peak.
On the other hand, in the DSC curves of FIGS. The number of peaks is one single.

In addition, when measuring thermophysical properties by differential scanning calorimetry (DSC method) here, in accordance with JIS K 7122 transition heat measurement method, first, an aluminum pan containing about 5 mg of a sample is placed in a nitrogen atmosphere, (1) After the temperature was raised at 10°C/min and held at 110°C for 5 minutes to completely melt, (2) the temperature was lowered at 5°C/min to 30°C and held at 30°C for 5 minutes. After recrystallization, (1) and (2) were repeated to obtain a melting curve (differential thermal curve) showing temperature-endothermic characteristics. Then, the endothermic (melting) peak of the endothermic property accompanying crystal melting was determined from the results of measuring the differential heat during the second and subsequent temperature rises.

Next, an evaluation test was conducted on the effect of suppressing the temperature rise of the refrigerant by the heat storage material compositions according to Examples 1 to 6 and the heat storage materials (phase change materials) according to Reference Examples 1 to 4.
In cooling systems for heat sources such as motors, batteries, and fuel cells, the upper limit temperature for cooling is, for example, around 100°C. evaluated.

Here, an evaluation apparatus shown in FIG. 1 was constructed in order to evaluate the effect of suppressing the temperature rise of the refrigerant.
Specifically, as shown in FIG. 1, 8 g of a predetermined medium (water) 22 corresponding to a coolant for cooling heat sources such as motors, batteries, and fuel cells is placed in a large container 21 (glass beaker). Further, a small container 11 (glass beaker) containing 3 g of solid heat storage material composition 1 (each phase change material in the reference example) was placed in the medium 22 . Then, the small container 11 enclosing the heat storage material composition 1 (each phase change material in the reference example) and the large container 21 containing the medium 22 are immersed in an oil bath 23 at 95°C, and the temperature of the medium 22 is 40. C. to reach 90.degree. C. (required time) was measured with a thermometer 24 immersed in the medium 22. The temperature of the oil bath 23 was maintained at a constant temperature of 95°C.
The results of evaluation tests conducted using the heat storage material compositions 1 of Examples 1 to 6 and the phase change materials of Reference Examples 1 to 4 are shown in the lower column of Table 1. The control in Table 1 is the result when the large container 21 containing only the medium 22 is immersed in the oil bath 23 and measured in the same manner.

As shown in Table 1, in the heat storage material compositions according to Examples 1 to 6, the high-melting-point paraffin wax containing hexatriacontane as the main component and 1-hexadecanol as a higher alcohol contained in the medium The time required for the temperature of No. 22 to reach 90° C. from 40° C. was equal to or longer than those of Reference Examples 1 and 2 in which they were blended alone.
In other words, according to the heat storage material compositions according to Examples 1 to 6, even if the high melting point paraffin wax and the higher alcohol are combined, the high melting point paraffin wax or 1-hexadecanol was blended alone. Compared with Reference Example 2, a high temperature rise suppressing effect equal to or greater than that time was shown.

As described above, in the heat storage material compositions according to Examples 1 to 6, the high melting point paraffin wax containing hexatriacontane as the main component and 1-hexadecanol as the higher alcohol are mixed so that they do not overlap each other (continuous It is possible to absorb heat and store heat in a plurality of different temperature ranges, and even if it is mixed without granulation such as encapsulation in microcapsules, the heat storage performance will not be deactivated. As can be seen from the differential scanning calorimetry shown in FIG. 11, even when compared with Comparative Examples 1 and 2 in which high melting point paraffin wax and 1-hexadecanol were used alone, high melting point paraffin wax and 1 -Hexadecanol maintains the inherent latent heat, and has a high effect of suppressing the temperature rise of the medium 22 and mitigating it.

In particular, according to the experimental research of the present inventors, as shown in Example 1, the latent heat storage material consists only of high-melting paraffin wax whose main component is hexatriacontane and 1-hexadecanol as a higher alcohol. , more preferably 250 to 500 parts by mass of 1-hexadecanol, which is a heat storage material on the low melting point side, with respect to 100 parts by mass of the high melting point paraffin wax, which is the heat storage material on the high melting point side, More preferably, it is within the range of 300 to 500 parts by mass, and the total amount of high melting point paraffin wax and 1-hexadecanol is more preferably 10 to 55 parts by mass per 100 parts by mass. Parts by mass, more preferably in the range of 15 to 30 parts by mass, 1-hexadecanol more preferably in the range of 45 to 90 parts by mass, still more preferably in the range of 70 to 90 parts by mass, The time required to reach 90° C. is longer than in Comparative Examples 1 and 2, which are used alone, and it is possible to improve the effect of suppressing the temperature rise of the refrigerant (medium 22) and alleviating it. This is because, with a predetermined composition, the liquid phase of 1-hexadecanol and the solid phase of the high melting point paraffin wax coexist with a temperature rise, and the balance of the solid-liquid ratio in the coexistence state becomes favorable, and heat is transferred to the high melting point paraffin wax. It can be inferred that this is because transmission is improved.

Furthermore, in Examples 4 to 6, a high melting point paraffin wax whose main component is hexatriacontane and a low melting point paraffin wax whose main component is docosane, which has a lower melting point than 1-hexadecanol as a higher alcohol. By blending, it is possible to obtain a good heat storage effect at low cost. In addition, since heat can be stored from the lower temperature side, the heat load on the heat source and its surroundings can be reduced. Furthermore, by blending high-melting paraffin wax whose main component is hexatriacontane and trimethylolethane whose phase change temperature is higher than the melting point of 1-hexadecanol as a higher alcohol, the volume change due to phase change is relatively small. It can also store heat at higher temperatures.

In particular, when looking at Control and Reference Example 4, trimethylolethane alone does not have the effect of suppressing the temperature rise of the refrigerant (medium 22), but a predetermined amount of trimethylolethane is added to the combination of high-melting paraffin wax and higher alcohol. By doing so, the effect of suppressing temperature rise can be enhanced by exhibiting the heat storage effect due to the phase change between the solid phases of trimethylolethane on the higher temperature side. The heat storage effect of trimethylolethane is exhibited by the balance of the solid-liquid ratio in the coexistence of the liquid phase of 1-hexadecanol and high-melting paraffin wax and the solid phase of trimethylolethane as the temperature rises. It can be assumed that this is because the heat transfer to ethane is improved. Furthermore, by blending low-melting paraffin wax whose main component is docosane, heat storage starts at a lower temperature side, suppressing a rapid temperature rise of the refrigerant, and heat storage starts at a lower temperature side. Therefore, the heat transfer to the high-melting-point component side is improved, and their heat storage and heat absorption are effectively exhibited, so that it is possible to suppress the temperature rise of the refrigerant and improve the mitigation effect.
From this, it is possible to improve the effect of suppressing the temperature rise of the refrigerant (medium 22) and mitigating the temperature rise more than Reference Examples 1 to 4, and more than Examples 1 to 3, and the time required to reach 90 ° C. is lengthened. can.

According to the experimental research of the present inventors, as shown in Examples 4 and 5, even if 1-hexadecanol is less than 250 parts by mass with respect to 100 parts by mass of high-melting paraffin wax, With respect to 100 parts by mass of the total amount of high-melting paraffin wax and 1-hexadecanol, trimethylolethane is preferably blended in the range of 30 parts by mass to 85 parts by mass, and preferably 5 parts by mass to 40 parts by mass. A low-melting paraffin wax containing docosane as the main component is blended within the range of parts by mass. With respect to 100 parts by mass of the total amount of high-melting paraffin wax, low-melting paraffin wax, 1-hexadecanol and trimethylolethane, trimethylolethane is preferably blended in the range of 20 to 40 parts by mass, preferably contains 5 to 35 parts by mass of a low-melting paraffin wax containing docosane as the main component.
With such a blending, the time required to reach 90° C. can be made longer than when each latent heat storage material is used alone, or when the latent heat storage material is only a high-melting paraffin wax and a higher alcohol. Therefore, it is possible to suppress the temperature rise of the refrigerant (medium 22) and improve the mitigation effect.

As described above, the heat storage material composition according to the present embodiment is a heat storage material composition containing paraffin wax and higher alcohol, wherein the melting point difference between the paraffin wax and the higher alcohol is 20°C or more and 40°C. °C or less.

Therefore, according to the heat storage material composition according to the present embodiment, by mixing paraffin wax and higher alcohol having a melting point difference of 20° C. or more and 40° C. or less, In the DSC curve obtained by the measurement, the endothermic peaks do not overlap, and there are multiple peaks (double peaks) in which multiple solid-liquid phases of paraffin wax and higher alcohol coexist, and paraffin wax and The amount of latent heat possessed by each of the higher alcohols is maintained, and a high heat storage effect can be exhibited as a whole. That is, it is possible to store heat by latent heat when each of the paraffin wax and the higher alcohol undergoes a phase change in a plurality of different temperature zones between the vicinity of the melting point of the high-melting paraffin wax and the vicinity of the melting point of the higher alcohol. It has a heat storage effect in multiple temperature ranges. In addition, even if the paraffin wax and the higher alcohol are mixed without forming particles such as microencapsulation, the heat storage function of the paraffin wax and the higher alcohol is not deactivated, and heat storage loss and heat storage dispersion are unlikely to occur, and the paraffin wax and the higher alcohol are mixed. The latent heat content of each of the waxes and higher alcohols is maintained. Furthermore, coexistence of a plurality of solid-liquid phases of paraffin wax and higher alcohol improves heat transfer.

Therefore, if the heat storage material composition is enclosed in a container or the like and provided in contact with the refrigerant in a cooling circuit for cooling a heat source such as a motor, a battery of a secondary battery, or a fuel cell, the refrigerant temperature rise can be effectively suppressed and mitigated. In particular, since the heat storage effect is exhibited stepwise from the low temperature side to the high temperature side in this way, the heat applied to the refrigerant due to sudden high heat generation of heat sources such as motors, batteries, fuel cells, etc. and high temperature environmental conditions. Even when the energy increases rapidly, the rapid temperature rise of the refrigerant can be effectively suppressed, the temperature rise rate can be moderated, and the decrease in cooling efficiency can be suppressed. By exhibiting the heat storage effect in stages from the low temperature side to the high temperature side, the heat storage effect is exhibited even at low temperatures, so that the heat load on the heat source and its surroundings can be reduced.
Furthermore, since heat can be stored by latent heat of phase change in a plurality of different temperature zones, it is possible to cope with a wide range of temperature design of the cooling circuit, and it has high versatility that can correspond to a wide range of temperature design of the cooling circuit.

Particularly preferably, a high melting point paraffin wax having a melting point in the range of 65° C. or higher and 85° C. or lower, for example, a high melting point paraffin containing hexatriacontane as a main component and a high melting point paraffin wax having a melting point of 20° C. to 40° C. higher than that of the high melting point paraffin wax are preferably used. ℃ low and having a carbon number of 13 or more and 18 or less higher alcohol, such as 1-hexadecanol, for example, a cooling circuit for cooling them in heat sources such as motors, batteries, and fuel cells Since the upper limit temperature of the refrigerant is set to around 100° C., it can be suitably used for suppressing the temperature rise of such a refrigerant.

That is, the paraffin wax has a melting point (phase transition point) in the range of 65° C. or more and 85° C. or less, and if the melting point is higher than the melting point of the higher alcohol, the liquid phase of the higher alcohol and the paraffin wax will separate as the temperature rises. The coexistence balance of a plurality of phases with the solid phase enables good heat transfer to the paraffin wax, and the heat storage performance of paraffin is fully exhibited without heat storage loss of paraffin. For example, it is suitable for suppressing the temperature rise of a refrigerant whose upper limit temperature is set to around 100 ° C., and it can exhibit a high temperature rise suppressing effect for such a refrigerant, and the time until the refrigerant reaches the upper limit temperature is effective. can last as long as

In addition, when the higher alcohol is an aliphatic alcohol having a carbon number of 13 or more and 18 or less and preferably a melting point of 35° C. or more and 60° C. or less, a high-purity alcohol can be obtained at low cost, so that stable heat storage can be achieved. performance can be demonstrated. In addition, since the phase change is difficult to occur in a normal state with a small heat load, deterioration due to repeated phase changes, that is, a decrease in the amount of latent heat, is unlikely to occur. Therefore, it is possible to obtain the effect of suppressing the temperature rise of the refrigerant that is stable for a longer period of time.

In particular, in Examples 1 to 6, high-melting paraffin containing hexatriacontane as the main component is used, and 1-hexadecanol is used as the higher alcohol. It is chemically stable both in the state and the liquid phase state, has a high latent heat capacity, has a suitable solid-liquid ratio balance, and exhibits good heat transfer to the high melting point paraffin wax, exhibiting a high heat storage effect. In a normal state with no heat load, the phase change is unlikely to occur, and there is no fear that excessive repetition of the phase change will cause early deterioration or alteration due to the heat history, resulting in a decrease in the latent heat amount. Therefore, it is possible to obtain a long-term, stable effect of suppressing the temperature rise of the refrigerant.

That is, these high-melting-point paraffins and higher alcohols are mixed (dry blended) without being granulated by microencapsulation or the like, and the original heat storage performance of each material can be achieved without reacting with each other and deactivating the heat storage function. It is chemically stable in both solid and liquid phases, and has a high heat storage capacity as a whole by undergoing a phase change near its own melting point. The coexistence of the phases also improves heat transfer. Therefore, the effect of suppressing the temperature rise of the predetermined refrigerant is high.

According to the heat storage material composition according to the present embodiment, by further blending the solid-solid phase change type phase change material, it is possible to relatively suppress the increase in volume change due to phase change, so that the heat source It is possible to reduce the size and simplification of a container or bag containing a heat storage material composition when applied to suppress the temperature rise of a refrigerant in a cooling circuit for cooling a heat storage material composition. In addition, since the relative amounts of higher alcohol and paraffin wax, which are solid-liquid phase change materials, are reduced, leakage and seepage are less likely to occur, increasing the degree of freedom in choosing a container that prevents leakage and seepage. can be done.
By mixing higher alcohol and high-melting-point paraffin wax, it is possible to improve the effect of suppressing the temperature rise of the refrigerant by improving the heat transfer due to the improvement of the coexistence balance of the solid-liquid two phases.

In particular, as shown in Examples 4 to 6, the cost can be reduced by using inexpensively available trimethylolethane (C ₅ H ₁₂ O ₃ ) as the solid-solid phase transition type phase change material. is. In particular, trimethylolethane (C ₅ H ₁₂ O ₃ ) is chemically stable even when mixed with higher alcohols and paraffin wax, and does not easily lose heat storage performance due to repeated use. Even if it is applied to a refrigerant whose temperature is set, it does not undergo sublimation or the like, and by exhibiting a high heat storage function at a high temperature, it is possible to improve the effect of suppressing the temperature rise of the refrigerant.

According to the heat storage material composition according to the present embodiment, the cost can be reduced by blending the paraffin wax having a melting point difference of 20 to 40° C. and the low melting point paraffin wax having a lower melting point than the higher alcohol. , By starting the phase change at a lower temperature side, the refrigerant can be kept at a low temperature and the heat load on the heat source and its surroundings can be reduced. , it is possible to improve the effect of suppressing the temperature rise of the refrigerant.

Further, the high-melting paraffin waxes containing 1-hexadecanol and hexatriacontane as main components and the low-melting-point paraffin waxes containing trimethylolethane and docosane as main components used in Examples 1 to 6 have little odor. Also, since it is neither toxic nor perishable, it is easy to handle and has good working environment. Furthermore, it has good thermal stability and is resistant to oxidative deterioration, so it can exhibit stable and high heat storage properties for a long period of time. Further, since no particles such as microfilm encapsulation are used, high heat storage efficiency can be obtained at low cost by not using capsules or cross-linking agents.

Such a heat storage material composition according to the present embodiment can exhibit a heat storage effect in a plurality of temperature ranges by combining paraffin wax and higher alcohol having a melting point difference of 20 to 40 ° C. In addition to being suitable for suppressing temperature rise of refrigerants used for cooling fuel cells, etc., various parts such as electronic materials, magnetic materials, catalyst materials, structural materials, optical materials, medical materials, automobile materials, construction It can also be applied to suppress the temperature rise of parts such as materials, and can be widely used for heat storage.

In addition, according to the heat storage material composition according to the present embodiment, by containing paraffin wax and higher alcohol, the heat is absorbed by changing the phase from solid to liquid as the temperature rises due to heat generation of the heat source. Heat is dissipated through a phase change from liquid to solid as the temperature drops due to the stoppage of operation of the heat source. In particular, the solid-liquid phase transition type latent heat storage material such as paraffin wax or higher alcohol has the property that the state change is slow and the stored latent heat is gradually released to the outside when the amount of heat is not supplied from the outside. doing. For this reason, it also has a heat retaining effect due to the heat radiation associated with such solidification. Due to the heat insulating effect, for example, when the heat storage material composition according to the present embodiment is placed in a unit such as a battery, it is possible to maintain the optimum operating temperature. In particular, in a low-temperature environment in winter, it is possible to prevent a decrease in electromotive force due to low temperature by heat insulation, and to maintain good battery performance during startup and charging.

By the way, the above description relates to a cooling system that cools a heat source using a refrigerant, and includes a cooling circuit for cooling the heat source with a refrigerant that flows through an internal space, and a cooling circuit provided in contact with the refrigerant in the cooling circuit. and a heat storage material comprising a heat storage material having a melting point difference of 20° C. or more and 40° C. or less, and a heat storage material composition in which a paraffin wax and a higher alcohol are mixed is enclosed in a container. It can also be regarded as the invention of the system.

According to the cooling system of the above embodiment, the high melting point paraffin wax and the higher alcohol are microencapsulated by the heat storage material composition comprising a mixture of the paraffin wax and the higher alcohol having a melting point difference of 20° C. or more and 40° C. or less. Even when mixed without granulating, the heat storage function of the high-melting paraffin wax and the higher alcohol is not deactivated, and the inherent latent heat of the high-melting paraffin wax and the higher alcohol is maintained, resulting in a high melting point as a whole. The heat storage capacity of the paraffin wax and the higher alcohol does not decrease significantly, and the coexistence of the solid-liquid two phases allows good heat transfer and exhibits a high heat storage effect. Since the heat storage material in which such a heat storage material composition is enclosed in a container is provided in contact with the refrigerant, the heat energy added to the refrigerant is absorbed and stored in the heat storage material, thereby increasing the temperature of the refrigerant. Suppression is possible, and a high cooling effect can be maintained.

In particular, according to such a heat storage material, it is possible to store heat by phase change latent heat in a plurality of different temperature zones near the melting point of high-melting paraffin wax and near the melting point of higher alcohol, so that the load of the heat source is high. Therefore, even when the heat energy applied to the refrigerant increases abruptly, the rapid temperature rise of the refrigerant can be effectively suppressed, the temperature rise rate can be moderated, and the decrease in cooling efficiency can be suppressed. In addition, since the heat storage effect is exhibited even at low temperatures, the heat load on the heat source and its surroundings can be reduced. Furthermore, it can be applied to a wide range of temperature design of the cooling circuit, and has a wide range of application for suppressing the temperature rise of the refrigerant.

Therefore, it is possible to enhance the cooling effect at low cost without enlarging the cooling system and without increasing the amount of power consumption. In particular, a space-saving arrangement in which a container containing the heat storage material composition is in contact with the refrigerant flowing in the internal space of the cooling circuit allows the cooling system to be used as it is without being enlarged or modified. It is possible to enhance the cooling effect.

Here, the heat source is, for example, a motor, a secondary battery, a fuel cell, or the like.
Examples of the refrigerant include air, water, oil, carbon dioxide, propane, hydrocarbons such as butane and isobutane, ammonia, fluorocarbon-based refrigerants, freon-based refrigerants, and the like.
The cooling circuit allows a coolant to flow through the internal space to cool the heat source, and is incorporated, for example, between battery cells of a battery pack or module in the case of a battery or the like.
In addition, the container may be any container as long as it can prevent leakage and seepage even when the heat storage material composition undergoes a phase change and becomes a liquid phase. Polypropylene, polystyrene, polyamide, nylon, polyester, polyethylene terephthalate) can be used. Aluminum may be vapor-deposited or laminated on resin.

In carrying out the present invention, the configuration, components, blending, manufacturing method, etc. of other parts of the heat storage material composition and the cooling system using the same are not limited to the above examples. Additives can be added as required.
Further, all of the numerical values given in the embodiments and examples of the present invention do not indicate critical values, and certain numerical values are values determined from manufacturing costs, forms that are easy to manufacture, etc. Since these are preferred values, even if the above numerical values are slightly changed within the permissible values, the implementation thereof is not denied.

Claims (10)

A heat storage material composition that contains paraffin wax and a higher alcohol and is solid at room temperature ,
The paraffin wax has a melting point of 65° C. or higher and 85° C. or lower,
The heat storage material composition , wherein the higher alcohol has a melting point lower than that of the paraffin wax, and a melting point difference between the higher alcohol and the paraffin wax of 20°C or more and 40°C or less . 2. The heat storage material composition according to claim 1 , wherein the paraffin wax contains hexatriacontane as a main component. 3. The heat storage material composition according to claim 1, wherein the higher alcohol is an aliphatic alcohol having 13 or more and 18 or less carbon atoms. 4. The heat storage material composition according to claim 1, wherein the higher alcohol is 1-hexadecanol. The amount of the paraffin wax and the higher alcohol compounded is such that, of the paraffin wax and the higher alcohol, 100 parts by mass of the paraffin wax, which is a heat storage material with a high melting point, is added to 100 parts by mass of the high-grade heat storage material, which is a heat storage material with a low melting point. 5. The heat storage material composition according to any one of claims 1 to 4 , wherein the alcohol is in the range of 80 to 550 parts by mass. The amount of the high-melting paraffin wax and the higher alcohol is such that the total amount of the high-melting paraffin wax and the higher alcohol is 100 parts by mass, and the heat storage material having the higher melting point among the paraffin wax and the higher alcohol is Claims 1 to 5 , wherein the paraffin wax is in the range of 10 to 60 parts by mass, and the higher alcohol as the heat storage material on the low melting point side is in the range of 40 to 90 parts by mass. The heat storage material composition according to any one of . 7. The heat storage material composition according to claim 1, further comprising a solid-solid phase transition type phase change material. 8. The heat storage material composition according to claim 7 , wherein the solid-solid phase change type phase change material is trimethylolethane. The content of the solid-solid phase transition type phase change material is in the range of 5 to 95 parts by mass with respect to 100 parts by mass of the total amount of the high-melting paraffin wax and the higher alcohol. The heat storage material composition according to claim 7 or 8 . 10. The heat storage material composition according to claim 1 , further comprising a low melting point paraffin wax having a lower melting point than the paraffin wax and the higher alcohol.

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