Thermal regulation of electrical device

Abstract

The invention relates to thermal conditioning of an electrical device. The present invention relates to the use of a heat transfer composition comprising at least one refrigerant selected from the group consisting of halogenated hydrocarbons, perhalogenated hydrocarbons, fluorinated ketones, fluorinated ethers and combinations thereof and at least one dielectric fluid for cooling a device, such as a battery of an electric or hybrid vehicle, the heat transfer composition has a volume resistivity of greater than or equal to 106 Omega.cm at 25 DEG C.

Description

[0001] This application is a divisional application of patent application No. 202080093882.4, filed on October 19, 2020, entitled "Thermal Regulation of an Electrical Device". Technical Field

[0002] This invention relates to the use of a heat transfer composition comprising at least one refrigerant fluid and at least one dielectric fluid for regulating the temperature of equipment such as batteries, electrical components, or fuel cell batteries (especially for cooling the equipment). The invention is particularly applicable to batteries for electric or hybrid vehicles. Background Technology

[0003] In many applications, particularly in the cooling of batteries, electronic components, and fuel cell systems, the need to dissipate high heat fluxes is fundamental. Liquid-vapor phase change cooling has proven to be an effective solution for dissipating large amounts of heat while maintaining uniform system temperature.

[0004] In particular, batteries in electric or hybrid vehicles perform optimally under specific operating conditions, especially within a fairly specific temperature range. Therefore, autonomy in electric or hybrid vehicles is problematic in cold climates, especially since the high heating requirements consume a large portion of the stored electrical energy. Furthermore, the available battery charge is low at low temperatures, causing driving difficulties. In addition, the cost of the battery significantly impacts the overall cost of electric or hybrid vehicles.

[0005] Conversely, battery cooling is a primary safety concern. Various dielectric oils can be used to cool batteries in electric or hybrid vehicles. However, when rapid charging of the battery is required, dielectric oil alone is insufficient for effective cooling, especially due to the non-evaporation caused by the high boiling points of these oils. In such cases, more volatile and less viscous fluids are needed. However, these fluids typically have higher vapor pressures than those observed with dielectric oils, which may necessitate reinforcing the battery casing (and thus increasing its weight) to withstand the pressure. Furthermore, these fluids are more expensive than dielectric oils.

[0006] In addition, it is important to use non-flammable or non-combustible compositions near the battery to eliminate any safety risks associated with the use of these compositions.

[0007] FR 2973809 relates to the use of zeolite adsorbents to improve the thermal stability of oils that undergo temperature changes in cooling fluid compositions.

[0008] FR 2962442 relates to stable compositions comprising 2,3,3,3-tetrafluoropropylene for use in refrigeration and air conditioning.

[0009] US 2014 / 057826 relates to heat transfer compositions comprising at least one hydrochlorofluoroolefin for use in air conditioning, refrigeration and heat pump applications or for cleaning products, components, substrates or other articles containing substances to be cleaned.

[0010] WO 2019 / 242977 relates to fluid-insulated switchgear, which includes a fluid compartment filled with an electrically insulating fluid and an electrical conductor located in the fluid compartment and electrically insulated by the electrically insulating fluid.

[0011] WO 2019 / 162598 relates to the use of refrigerants containing 2,3,3,3-tetrafluoropropylene to maintain the temperature of batteries in electric or hybrid vehicles within a certain temperature range.

[0012] WO 2019 / 162599 relates to the use of a refrigerant containing 2,3,3,3-tetrafluoropropylene to preheat the battery of an electric or hybrid vehicle during startup.

[0013] WO 2019 / 197783 relates to a method for cooling and / or heating an object or fluid in a motor vehicle via a system comprising a vapor compression circuit in which a first heat transfer composition flows and a secondary circuit in which a second heat transfer composition flows. It is necessary to ensure optimal battery operation in electric or hybrid vehicles to provide a safe and efficient battery without increasing battery-related costs. Summary of the Invention

[0014] This invention primarily relates to the use of heat transfer compositions for regulating the temperature of equipment selected from batteries, electrical components, or fuel cell batteries, said heat transfer compositions comprising at least one refrigerant selected from halogenated hydrocarbons, fluorinated ketones, fluorinated and perhalogenated ethers, and combinations thereof, and at least one dielectric fluid, said heat transfer compositions having a temperature greater than or equal to 10 at 25°C. 6 Volume resistivity in Ω·cm.

[0015] In some embodiments, the refrigerant comprises or is 1-chloro-3,3,3-trifluoropropylene, preferably in the E form.

[0016] In some embodiments, the refrigerant is present in an amount of 10% to 80% by weight, preferably 10% to 60% by weight, and even more preferably 10% to 40% by weight, relative to the total weight of the heat transfer composition.

[0017] In some embodiments, the dielectric fluid is selected from mineral dielectric oil, synthetic dielectric oil, and vegetable dielectric oil; the synthetic fluid is preferably an aromatic hydrocarbon selected from alkylbenzene, alkyl diphenyl ethane, alkyl naphthalene, methyl polyarylmethane, and combinations thereof; the dielectric fluid is more preferably a mixture of benzyltoluene and dibenzyltoluene.

[0018] In some embodiments, the dielectric fluid is present in an amount of 20% to 90% by weight, preferably 40% to 90% by weight, more preferably 40% to 60% by weight, relative to the total weight of the heat transfer composition.

[0019] In some embodiments, the heat transfer composition has a liquid saturation temperature of 20 to 80°C, and preferably 30 to 70°C, at a pressure of 1 bar.

[0020] In some embodiments, the heat transfer composition has a breakdown voltage of 20 kV or greater at 20°C.

[0021] In some embodiments, the heat transfer composition consists essentially of: 1-chloro-3,3,3-trifluoropropene; and a mixture of monobenzyltoluene and dibenzyltoluene.

[0022] In some embodiments, the heat transfer composition consists essentially of 1-chloro-3,3,3-trifluoropropylene and a polyol ester synthesized from pentaerythritol.

[0023] In some embodiments, the heat transfer composition exchanges heat with another heat transfer composition (preferably contained in a vapor compression loop).

[0024] In some implementations, the above uses are for cooling the equipment.

[0025] In some embodiments, the temperature of the device is regulated by placing the device in direct contact with the heat transfer composition, preferably by immersing the device in the heat transfer composition.

[0026] In some implementations, the device is a battery from an electric or hybrid vehicle.

[0027] In some embodiments, the above uses are performed during the charging of the vehicle's battery, which is preferably fully charged within a time of less than or equal to 30 minutes, and more preferably less than or equal to 15 minutes, from the time it is fully discharged.

[0028] This invention fulfills the aforementioned needs. Specifically, it ensures optimal operation of batteries in devices, particularly electric or hybrid vehicles, to provide safe and efficient batteries without increasing battery-related costs.

[0029] This is achieved by using a heat transfer composition comprising at least one refrigerant selected from halogenated hydrocarbons, fluorinated ketones, fluorinated and perhalogenated ethers, and combinations thereof, and at least one dielectric fluid, wherein the heat transfer composition has a temperature of 10 ℃ or higher at 25°C. 6 Volume resistivity in Ω·cm.

[0030] Throughout the following text, consideration is given to the case where the device is a battery, particularly a battery for an electric or hybrid vehicle. However, the invention can be implemented in a similar manner with other device items, particularly electrical components or fuel cell batteries.

[0031] Specifically, the combination of dielectric fluid and refrigerant enables the provision of volatile and low-viscosity compositions (especially compared to compositions composed of dielectric fluid), which allows for increased battery efficiency and lifespan without increasing costs, particularly during fast charging.

[0032] The composition has a strength of 10 at 25°C or higher. 6 The fact that the volume resistivity is Ω·cm (and preferably greater than or equal to 20 kV at 20°C) ensures that the dielectric properties of the composition are compatible with use in the vicinity of the device, especially in the vicinity of the battery in direct or indirect contact with it.

[0033] The refrigerant enables the reduction of the viscosity of the dielectric fluid and makes the composition more volatile and therefore more efficient. The refrigerant also enables the reduction of the liquid saturation temperature of the composition (compared to compositions containing only dielectric fluid) and improves the cooling efficiency of the battery.

[0034] Furthermore, the vapor pressure of the composition is typically lower than that of the refrigerant alone, which allows for fewer restrictions on reinforcing the battery housing to withstand pressure and thus reduces vehicle weight, thereby improving vehicle performance.

[0035] The cost of the combination is usually lower than the cost of the refrigerant alone.

[0036] Advantageously, the combination of refrigerant and dielectric fluid also makes it possible to obtain non-flammable or non-combustible compositions. Attached Figure Description

[0037] Figure 1 To illustrate the variation of the liquid saturation temperature of the heat transfer composition with refrigerant content at a pressure of 1 bar (see the Examples section below). Temperatures are shown on the y-axis (°C), and the dielectric fluid content is shown on the x-axis (wt%). Detailed Implementation

[0038] The invention will now be described in more detail and in a non-limiting manner in the following description.

[0039] heat transfer composition

[0040] The heat transfer composition according to the invention comprises at least one refrigerant and at least one dielectric fluid.

[0041] The term "refrigerant" refers to a fluid that can absorb heat by evaporating at low temperatures and low pressures and release heat by condensing at high temperatures and high pressures.

[0042] The refrigerant is selected from halogenated hydrocarbons, perhalogenated hydrocarbons, fluorinated ketones, fluorinated ethers, and combinations thereof.

[0043] Among halogenated hydrocarbons, hydrofluorocarbons, hydrochlorofluorocarbons, hydrofluoroolefins, hydrochloroolefins, and hydrochlorofluoroolefins may be mentioned.

[0044] For example, the refrigerant can be selected from: 1,1,1,4,4,4-hexafluorobut-2-ene (HFO-1336mzz, E or Z isomer), 1-chloro-3,3,3-trifluoropropene (HCFO-1233zd, E or Z isomer), 3,3,4,4,4-pentafluorobut-1-ene (HFO-1345fz), 2,4,4,4-tetrafluorobut-1-ene (HFO-1354mfy), 1,1,2-trifluoroethylene (HFO-1123), 1,1 1,3,3-Pentafluoropropane (HFC-245fa), 2,3,3,3-Tetrafluoropropene (HFO-1234yf), 1,3,3,3-Tetrafluoropropene (HFO-1234ze, E or Z isomer), difluoromethane (HFC-32), 1,1,1,2-Tetrafluoroethane (HFC-134a), 1,1,2,2-Tetrafluoroethane (HFC-134), 1,1-Difluoroethane (HFC-152a), pentafluoroethane (HFC-125) 1,1,1,3,3-Pentafluorobutane (HFC-365mfc), fluoroethane (HFC-161), 1,1,1,2,3,3,3-Hepanofluoropropane (HFC-227ea), 1,1,1-Trifluoropropane (HFC-263fb), 1,2-Dichloroethylene (E or Z), and combinations thereof.

[0045] Among perhalogenated hydrocarbons, perfluorinated compounds may be mentioned, such as dodecylfluoropentane, tetradecylfluorohexane, hexadecylfluoroheptane, and combinations thereof.

[0046] Examples of fluorinated ketones that may be mentioned include fluorinated monoketones, perfluorinated monoketones such as 1,1,1,2,2,4,5,5,5-nonafluoro-4-(trifluoromethyl)-3-pentanone, and combinations thereof.

[0047] Among fluorinated ethers, hydrofluoroethers such as methoxynonfluorobutane (HFE7100), ethoxynonfluorobutane (HFE-7200), 1-methoxyheptafluoropropane (HFE-7000), perfluoropolyethers, and combinations thereof may be mentioned.

[0048] The refrigerant may contain several, such as two, three, four or five compounds as described above.

[0049] In some preferred embodiments, the refrigerant comprises HFO-1233zd in the form of E or Z, and more preferably in the form of E.

[0050] Preferably, the heat transfer composition according to the invention comprises essentially only one compound as a refrigerant. In this case, the refrigerant is preferably in the form of E or Z, and more preferably in the form of E, HFO-1233zd.

[0051] The compositions according to the invention can be prepared by any means known to those skilled in the art, for example by simply mixing the various components of the compositions according to the invention.

[0052] The refrigerant according to the invention may have a liquid viscosity of 0.1 to 2 cP at 20°C, preferably 0.2 to 0.9 cP at 20°C. The viscosity can be measured according to the method shown in Example 2 below.

[0053] The refrigerant according to the invention can, in particular, have a boiling point (liquid saturation temperature) of 0 to 90°C, preferably 15 to 70°C, at 1 bar.

[0054] For the purposes of this invention, the term "dielectric fluid" means a fluid that is non-conductive (or only slightly conductive) but allows the application of electrostatic forces.

[0055] Preferably, the dielectric fluid is selected from mineral dielectric oils and synthetic dielectric oils, as well as mixtures thereof in any proportion.

[0056] The term "oil" refers to a fatty substance that is liquid at room temperature and immiscible with water. Oils are liquid fatty substances of vegetable, mineral, or synthetic origin.

[0057] Insulating (dielectric) oils have heat transfer fluid properties to allow the generated heat to dissipate.

[0058] The oil included in the heat transfer composition may be particularly selected from mineral dielectric oils, synthetic dielectric oils and vegetable dielectric oils, and combinations thereof.

[0059] According to one embodiment of the invention, the dielectric fluid comprises at least one mineral dielectric oil. Non-limiting examples of such mineral dielectric oils include paraffinic oils and naphthenic oils, such as the Nytro series dielectric oils (particularly Nytro Taurus, Nytro Libra, Nytro 4000X and Nytro 10XN) sold by Nynas and Dalia sold by Shell.

[0060] Mineral dielectric oils can be paraffin oils (i.e., linear or branched saturated hydrocarbons), such as NytroTaurus oil sold by Nynas and Dalia oil sold by Shell, or naphthenic oils (i.e., cyclic paraffins), such as Nytro Libra and Nytro 10XN oils sold by Nynas, aromatic compounds (i.e., cyclic unsaturated hydrocarbons containing one or more rings characterized by alternating double and single bonds) and non-hydrocarbon compounds.

[0061] According to another embodiment of the invention, the dielectric fluid is a synthetic dielectric oil. Non-limiting examples of such synthetic dielectric oils include aromatic hydrocarbons, aliphatic hydrocarbons, silicone oils, esters, polyesters and polyol esters, and mixtures of two or more of them in all proportions.

[0062] In aromatic hydrocarbons, reference may be made in a non-limiting manner to alkylbenzenes, alkyl diphenyl ethanes (e.g., phenylxylenyl ethane (PXE), phenylethyl phenyl ethane (PEPE), monoisopropyl biphenyl (MIPB), 1,1-diphenyl ethane (1,1-DPE), alkyl naphthalenes (e.g., diisopropyl naphthalene (DIPN), methyl polyarylmethanes (e.g., benzyltoluene (BT) and dibenzyltoluene DBT), and mixtures thereof. In said aromatic hydrocarbons, it should be understood that at least one ring is aromatic and one or more other rings optionally present may be partially or completely unsaturated. Most particularly preferred examples are those sold by Soltex Inc. and marketed by Arkema under the name Jarylec. ® Dielectric fluids sold, and SAS60E sold by JX Nippon Chemical Texas Inc.

[0063] In aliphatic hydrocarbons, poly(α)olefins (PAOs), such as polyisobutylene (PIB), or vinylidene-type olefins, such as those sold by Soltex Inc., may be mentioned in a non-limiting manner.

[0064] In the context of silicone oils, linear silicone oils of the polydimethylsiloxane type may be mentioned in a non-limiting manner, such as those produced by Wacker Corporation under the name Wacker. ® Those sold by AK.

[0065] In the context of synthetic esters, phthalic acid-type esters may be mentioned in a non-limiting manner, such as dioctyl phthalate (DOP) or diisononyl phthalate (DINP) (e.g., sold by BASF).

[0066] It may also be mentioned in a non-limiting manner as a product of polyols and organic acids, particularly those selected from saturated or unsaturated C4 to C5 groups. 22Esters are obtained by reactions between organic acids. Non-limiting examples of such organic acids include undecanoic acid, heptanoic acid, octanoic acid, palmitic acid, and mixtures thereof. Non-limiting examples of polyols that can be used to synthesize the above-mentioned esters include pentaerythritol used in the synthesis of the oil Mivolt DF7 Midel 7131 and MivoltDFK from M&I Materials.

[0067] Therefore, synthetic esters obtained from the reaction between polyols and organic acids are, for example, Midel 7131 from M&I Materials or Nycodiel series esters from Nyco.

[0068] In the context of natural esters and vegetable oils, non-limiting examples may include products derived from oily seeds or other natural sources. Non-limiting examples may include FR3™ or Envirotemp™ sold by Cargill, Inc., or Midel eN 1215 sold by M&I Materials, Inc.

[0069] The heat transfer composition according to the invention may contain one or more oils, such as two, three, four or five oils.

[0070] The preferred dielectric fluid is a mixture of benzyltoluene and dibenzyltoluene.

[0071] Another preferred dielectric fluid is a polyol ester made from pentaerythritol.

[0072] Preferably, the heat transfer composition according to the invention contains only one dielectric fluid. In this case, the dielectric fluid is preferably methylpolyarylmethane, and more particularly a mixture of benzyltoluene and dibenzyltoluene (e.g., Jarylec from Arkema). ® ); or polyol esters made from pentaerythritol.

[0073] Dielectric fluids can have a viscosity of 1 to 60 cP at 20°C, in particular, according to standard ISO 3104.

[0074] Dielectric fluids can have boiling points, especially those greater than 30°C, which can be measured by boiling determination.

[0075] The dielectric fluid may be present in the composition in an amount greater than 0 to less than 100 wt%, preferably 20 wt% to 90 wt%, more preferably 40 wt% to 90 wt%, and even more preferably 40 wt% to 60 wt%, relative to the total weight of the heat transfer composition.

[0076] For example, the content may be 1% to 10% by weight; or 10% to 15% by weight; or 15% to 20% by weight; or 20% to 25% by weight; or 25% to 30% by weight; or 30% to 35% by weight; or 35% to 40% by weight; or 40% to 45% by weight; or 45% to 50% by weight; or 50% to 55% by weight; or 55% to 60% by weight; or 60% to 65% by weight; or 65% to 70% by weight; or 70% to 75% by weight; or 75% to 80% by weight; or 80% to 85% by weight; or 85% to 90% by weight; or 90% to 95% by weight; or 95% to 99% by weight, relative to the total weight of the heat transfer composition.

[0077] The refrigerant may be present in the composition in an amount greater than 0 to less than 100% by weight, preferably 10% to 80% by weight, more preferably 10% to 60% by weight, and even more preferably 10% to 40% by weight, relative to the total weight of the heat transfer composition.

[0078] For example, the content may be 1% to 10% by weight; or 10% to 15% by weight; or 15% to 20% by weight; or 20% to 25% by weight; or 25% to 30% by weight; or 30% to 35% by weight; or 35% to 40% by weight; or 40% to 45% by weight; or 45% to 50% by weight; or 50% to 55% by weight; or 55% to 60% by weight; or 60% to 65% by weight; or 65% to 70% by weight; or 70% to 75% by weight; or 75% to 80% by weight; or 80% to 85% by weight; or 85% to 90% by weight; or 90% to 95% by weight; or 95% to 99% by weight, relative to the total weight of the heat transfer composition.

[0079] Preferably, the heat transfer composition according to the invention comprises a mixture of benzyltoluene and dibenzyltoluene (e.g., Jarylec from Arkema). ® And at least one fluorinated or fluorochlorohydrocarbon, for example, in a non-limiting manner, hydrofluoropropane, hydrofluoropropylene, hydrochlorofluoropropane, hydrochlorofluoropropylene, and mixtures thereof in all proportions.

[0080] Preferably, the heat transfer composition according to the invention comprises 1-chloro-3,3,3-trifluoropropene (preferably in the E form) and a mixture of monobenzyltoluene and dibenzyltoluene. Even more preferably, the heat transfer composition according to the invention consists essentially of or even entirely of: 1-chloro-3,3,3-trifluoropropene (preferably in the E form); and a mixture of monobenzyltoluene and dibenzyltoluene.

[0081] In other embodiments, the heat transfer composition according to the invention comprises a polyol ester made from pentaerythritol and at least one fluorinated or chlorofluorocarbon, for example, in a non-limiting manner, hydrofluoropropane, hydrofluoropropylene, hydrochlorofluoropropane, hydrochlorofluoropropylene, and mixtures thereof in all proportions thereof.

[0082] Preferably, the heat transfer composition according to the invention comprises 1-chloro-3,3,3-trifluoropropene (preferably in the E form) and a polyol ester made from pentaerythritol. Even more preferably, the heat transfer composition according to the invention consists essentially of or even entirely of 1-chloro-3,3,3-trifluoropropene (preferably in the E form) and a polyol ester made from pentaerythritol.

[0083] Compositions that can be used in the context of this invention may also contain one or more additives and / or fillers, selected in a non-limiting manner from antioxidants, passivators, pour point depressants, decomposition inhibitors, flavorings and tastes, colorants, preservatives, and mixtures thereof. The presence of decomposition inhibitors is particularly preferred.

[0084] Among the antioxidants that may be advantageously used in the composition, non-limiting examples include: phenolic antioxidants, such as butylated hydroxytoluene, butylated hydroxyanisole, tocopherol, and acetates (salts) of these phenolic antioxidants; amine-type antioxidants, such as phenyl-α-naphthylamine; diamine-type antioxidants, such as N,N'-bis(2-naphthyl)-p-phenylenediamine, ascorbic acid and its salts, esters of ascorbic acid, alone or as a mixture of two or more of them or as a mixture with other components such as green tea extract or coffee extract.

[0085] A particularly suitable antioxidant is Ionol, available from Brenntag. ® Products acquired through commercial purchase.

[0086] The passivating agents that can be used in the context of this invention are advantageously selected from triazole derivatives, benzimidazole, imidazole, thiazole, and benzothiazole. Non-limiting examples that may be mentioned include dioctylaminomethyl-2,3-benzotriazole and 2-dodecyl dithioimidazole.

[0087] Among the pour point lowering agents that may exist, non-limiting examples include fatty acid esters of sucrose and acrylic polymers such as poly(alkyl methacrylate) or poly(alkyl acrylate).

[0088] Preferred acrylic polymers are those with a content of 50,000 g·mol⁻¹. -1 and 500,000 g.mol -1 Those with molecular weights between [a certain range]. Examples of these acrylic polymers include polymers that may contain straight-chain alkyl groups comprising 1 to 20 carbon atoms.

[0089] Among these, and still as non-limiting examples, may be referenced to poly(methyl acrylate), poly(methyl methacrylate), poly(heptyl acrylate), poly(heptyl methacrylate), poly(nonyl acrylate), poly(nonyl methacrylate), poly(undecyl acrylate), poly(undecyl methacrylate), poly(tetrazyl acrylate), poly(tetrazyl methacrylate), poly(pentadecanyl acrylate), poly(pentadecanyl methacrylate), poly(heptadecyl acrylate), and poly(heptadecyl methacrylate).

[0090] One example of such a pour point lowering agent is available commercially from Sanyo Chemical Industries Ltd under the trade name Aclube.

[0091] According to the most particularly preferred aspect, the decomposition inhibitor is present as an additive. The decomposition inhibitor may be particularly selected from: carbodiimide derivatives such as diphenylcarbodiimide, xylylcarbodiimide, bis(isopropylphenyl)carbodiimide, bis(butylphenyl)carbodiimide; but may also be selected from: phenyl glycidyl ethers or esters, alkyl glycidyl ethers or esters, 3,4-epoxycyclohexylmethyl(3,4-epoxycyclohexane)carboxylic acid esters, compounds of the anthraquinone family, such as β-methylanthraquinone sold under the name "BMAQ", epoxide derivatives such as vinylcyclohexene diepoxide, 3,4-epoxy-6-methylcyclohexylmethylcarboxylic acid ester (3,4-epoxy-6-methylhexane), phenolic varnish-type epoxy resins, and diglycidyl epoxy ethers of bisphenol A, such as DGEBA or CEL 2021P, which are particularly available from Whyte Chemicals.

[0092] The total amount of additives is preferably no more than 5% by weight of the heat transfer composition, particularly 4% by weight, more particularly 3% by weight, and most particularly 2% by weight or even 1% by weight.

[0093] In some embodiments, the heat transfer composition contains impurities. When present, they may comprise less than 1% by weight, preferably less than 0.5% by weight, more preferably less than 0.1% by weight, more preferably less than 0.05% by weight, and more preferably less than 0.01% by weight, relative to the heat transfer composition.

[0094] The heat transfer composition according to the invention has a temperature of 10 at 25°C or greater. 6 Ω.cm, preferably greater than or equal to 10 7 Ω.cm or 10 8 Volume resistivity is measured in Ω·cm. The resistivity of a material indicates its ability to resist the flow of electric current. In other words, volume resistivity is an indicator of the dielectric properties of a composition. Volume resistivity is measured according to standard IEC 60247.

[0095] For example, the volume resistivity could be 10. 6 Up to 5×10 6 Ω.cm; or 5×10 6 Up to 10 7 Ω.cm; or 10 7 Up to 5×10 7 Ω.cm; or 5×10 7 Up to 10 8 Ω.cm; or 10 8 Up to 5×10 8 Ω.cm; or 5×10 8 Up to 10 9 Ω.cm; or greater than 10 9 Ω.cm.

[0096] Furthermore, the heat transfer composition according to the invention may have a breakdown voltage at 20°C greater than or equal to 20 kV, preferably greater than or equal to 20 kV, preferably greater than or equal to 30 kV, preferably greater than or equal to 50 kV, and more preferably greater than or equal to 100 kV. The term "breakdown voltage" refers to the minimum voltage required to make a portion of an insulator conductive. Therefore, this parameter is also an indicator of the dielectric properties of the composition. The breakdown voltage is measured according to standard IEC 60156.

[0097] For example, the breakdown voltage of the composition according to the invention at 20°C can be 25 to 30 kV; or 30 to 40 kV; or 40 to 50 kV; or 50 to 60 kV; or 60 to 70 kV; or 70 to 80 kV; or 80 to 90 kV; or 90 to 100 kV; or 100 to 110 kV; or 110 to 120 kV; or 120 to 130 kV; or 130 to 140 kV; or 140 to 150 kV.

[0098] The heat transfer composition according to the invention may also have a liquid saturation temperature of 20 to 80°C, preferably 30 to 70°C, at a pressure of 1 bar. For example, this temperature may be 20 to 25°C; or 25 to 30°C; or 30 to 35°C; or 35 to 40°C; or 40 to 45°C; or 45 to 50°C; or 50 to 55°C; or 55 to 60°C; or 60 to 65°C; or 65 to 70°C; or 70 to 75°C; or 75 to 80°C.

[0099] The heat transfer composition according to the invention may have a viscosity of 0.1 to 20 cP at 20°C, in particular, according to standard ISO 3104.

[0100] The heat transfer composition according to the invention is preferably non-flammable or preferably non-combustible.

[0101] Device for containing heat transfer composition

[0102] The heat transfer composition is contained in a device adapted to allow heat exchange between the composition and the battery, and preferably also with a secondary source.

[0103] The secondary source can be the environment or another heat transfer composition.

[0104] In some embodiments, the device prevents the heat transfer composition from directly contacting the vehicle's battery; the composition flows within a heat exchanger, heat pipe, or cooling plate. Dielectric properties ensure the safety of the device in the event of a puncture.

[0105] In some embodiments, the device allows the heat transfer composition to come into direct contact with the vehicle's battery. Preferably, the vehicle's battery is immersed in the heat transfer composition. In this case, the device may include a closed housing that houses all or part of the battery, within which the heat transfer composition is contained and in contact with the outer wall of the battery.

[0106] This allows the thermal properties of the heat transfer composition to be used most advantageously.

[0107] In some embodiments, the heat transfer composition is in a completely liquid state.

[0108] In other embodiments, the heat transfer composition is partially in a liquid state and partially in a gaseous state. The pressure in the housing containing the battery in direct contact or in the circuit in indirect contact can reach the vapor pressure of the heat transfer composition at the highest ambient temperature (e.g., 70°C in the case of a vehicle in sunlight). For example, the pressure in the housing can be maintained below 5 bar, or below 4 bar, or below 2 bar.

[0109] In cases where the battery is being charged rapidly (which involves rapid heating of the battery), cooling is particularly preferred by bringing the battery into direct contact with the heat transfer composition. This is because it allows for faster heat exchange between the battery and the heat transfer composition, thus maintaining cooling efficiency even when cooling demands increase.

[0110] When the battery is submerged, the heat transfer composition can exchange heat directly with the environment through the walls of the housing. Heat dissipation elements (fins, etc.) can be provided on the inner and / or outer surfaces of the walls. Alternatively, the heat transfer composition can exchange heat with another heat transfer composition through a heat exchanger located within the housing or through plates or channels on the walls of the housing. Alternatively, the heat transfer composition can undergo circulation into and out of the housing to exchange heat with the environment or with another heat transfer composition in a heat exchanger outside the housing.

[0111] Alternatively, the heat transfer composition can exchange heat with the battery via a heat exchanger. The device can then include a loop through which the composition flows. The heat exchanger can be, in particular, of a fluid / solid type, such as a plate exchanger.

[0112] Preferably, the circuit does not include a compressor. In other words, the circuit is not a vapor compression circuit.

[0113] The heat transfer composition may remain in a liquid state as it passes through a heat exchanger, or conversely, it may undergo complete or partial evaporation or condensation, depending on whether it is intended for cooling or heating.

[0114] Means for circulating the composition, such as pumps, may be provided.

[0115] When additional heat transfer compositions are provided, they may be present in a separate loop, which may be, in particular, a vapor compression loop. Heat exchange between the compositions takes place in a separate heat exchanger, which may be, for example, co-current or preferably counter-current.

[0116] The additional heat transfer composition itself can exchange heat with the environment through a separate heat exchanger. It can also optionally be used to heat or cool the air in the passenger compartment.

[0117] For this purpose, additional loops may include various branches with separate heat exchangers, in which additional heat transfer compositions may or may not flow, depending on the operating mode. Optionally, alternatively, or additionally, additional loops may include means for changing the flow direction of additional heat transfer compositions, such as including one or more three-way or four-way valves.

[0118] The term "countercurrent heat exchanger" refers to a heat exchanger in which heat is exchanged between a first fluid and a second fluid, wherein the first fluid at the inlet of the exchanger exchanges heat with the second fluid at the outlet of the exchanger, and the first fluid at the outlet of the exchanger exchanges heat with the second fluid at the inlet of the exchanger.

[0119] For example, a counter-current heat exchanger includes a device in which the flow of a first fluid and the flow of a second fluid are in opposite or nearly opposite directions. Exchangers operating in a cross-flow mode with a counter-current tendency are also included in counter-current heat exchangers.

[0120] Heat exchangers can be particularly those with U-tubes, horizontal or vertical tube bundles, coils, plates or fins.

[0121] Temperature control

[0122] This invention relates to the use of the heat transfer composition according to the invention for regulating the temperature of a battery by maintaining a uniform temperature. Preferably, the composition is used for cooling the battery. It can also be used for heating the battery. Heating and cooling can be performed alternately depending on the needs (outdoor temperature, battery temperature, battery operating mode).

[0123] Heating can also be achieved, at least in part, through resistance.

[0124] Therefore, the heat transfer composition according to the invention can be used exclusively for the uniform cooling of the battery, while other means such as resistance are used to heat it.

[0125] The term "battery temperature" usually refers to the temperature of the outer wall of one or more of its electrochemical cell units.

[0126] The temperature of a battery can be measured using a temperature sensor. If multiple temperature sensors are present on the battery, the battery temperature can be considered as the average of the measured temperatures. This invention makes it possible to significantly reduce the difference between temperatures measured at different points within the battery.

[0127] Temperature control can be performed while the vehicle's battery is charging. Alternatively, it can be performed while the battery is discharging, especially when the vehicle's engine is running. This is particularly effective in preventing the battery temperature from becoming excessively high due to external temperatures and / or the inherent heat generated by the battery during operation.

[0128] In particular, the battery can be charged quickly. Therefore, during a full charge of the battery (from the moment the battery is fully discharged) lasting less than or equal to 30 minutes, and preferably less than or equal to 15 minutes, the use of the composition according to the invention allows the battery temperature to be maintained within an optimal temperature range with a uniform distribution. This is advantageous because during fast charging, the battery tends to heat up rapidly and reach high temperatures, especially exhibiting hot spots that can affect its function, performance, and lifespan.

[0129] In some implementations, battery cooling is continuous over a period of time.

[0130] In some implementations, cooling and optionally heating allow the battery temperature to be maintained within an optimal range, particularly when the vehicle is running (engine running), and especially when the vehicle is moving. Specifically, if the battery temperature is too low, its performance is prone to significant degradation.

[0131] In some implementations, the temperature of the vehicle's battery can therefore be maintained between a minimum temperature t1 and a maximum temperature t2.

[0132] In some embodiments, the minimum temperature t1 is greater than or equal to 10°C and the maximum temperature t2 is less than or equal to 80°C; preferably, the minimum temperature t1 is greater than or equal to 15°C and the maximum temperature t2 is less than or equal to 70°C, and more preferably, the minimum temperature t1 is greater than or equal to 16°C and the maximum temperature t2 is less than or equal to 50°C.

[0133] Advantageously, a feedback loop exists to modify the facility's operating parameters based on the measured battery temperature, thereby ensuring that the desired temperature is maintained.

[0134] The external temperature during the period when the vehicle's battery temperature is maintained between the minimum temperature t1 and the maximum temperature t2 can be, in particular, -60 to -50°C; or -50 to -40°C; or -40 to -30°C; or -30 to -20°C; or -20 to -10°C; or -10 to 0°C; or 0 to 10°C; or 10 to 20°C; or 20 to 30°C; or 30 to 40°C; or 40 to 50°C; or 50 to 60°C; or 60 to 70°C.

[0135] The term "external temperature" refers to the ambient temperature outside the vehicle before and during the period when the vehicle's battery temperature is maintained between the minimum temperature t1 and the maximum temperature t2.

[0136] This invention includes the following aspects / implementations / features in any order and / or in any combination:

[0137] 1. A heat transfer composition for use in regulating the temperature of a device selected from batteries, electrical components, or fuel cell batteries, said heat transfer composition comprising at least one refrigerant selected from halogenated hydrocarbons, perhalogenated hydrocarbons, fluorinated ketones, fluorinated ethers, and combinations thereof, and at least one dielectric fluid, said heat transfer composition having a temperature greater than or equal to 10 at 25°C. 6 Volume resistivity in Ω·cm.

[0138] 2. Use of the foregoing or subsequent embodiments / features / aspects, wherein the refrigerant comprises or is 1-chloro-3,3,3-trifluoropropylene, preferably in the E form.

[0139] 3. Use of the foregoing or subsequent embodiments / features / aspects, wherein the refrigerant is present in a content of 10% to 80% by weight, preferably 10% to 60% by weight, and even more preferably 10% to 40% by weight, relative to the total weight of the heat transfer composition.

[0140] 4. Use of the foregoing or subsequent embodiments / features / aspects, wherein the dielectric fluid is selected from mineral dielectric oil, synthetic dielectric oil and vegetable dielectric oil; the synthetic fluid is preferably selected from alkylbenzene, alkyl diphenyl ethane, alkyl naphthalene, methyl polyarylmethane and combinations thereof, and the dielectric fluid is more preferably a mixture of benzyltoluene and dibenzyltoluene.

[0141] 5. Use of the foregoing or subsequent embodiments / features / aspects, wherein the dielectric fluid is present in an amount of 20% to 90% by weight, preferably 40% to 90% by weight, more preferably 40% to 60% by weight, relative to the total weight of the heat transfer composition.

[0142] 6. Use of the foregoing or subsequent embodiments / features / aspects, wherein the heat transfer composition has a liquid saturation temperature of 20 to 80°C, and preferably 30 to 70°C, at a pressure of 1 bar.

[0143] 7. Use of the foregoing or subsequent embodiments / features / aspects, wherein the heat transfer composition has a breakdown voltage of greater than or equal to 20 kV at 20°C.

[0144] 8. Use of the foregoing or subsequent embodiments / features / aspects, wherein the heat transfer composition is substantially composed of: 1-chloro-3,3,3-trifluoropropene; and a mixture of monobenzyltoluene and dibenzyltoluene.

[0145] 9. Use of the foregoing or subsequent embodiments / features / aspects, wherein the heat transfer composition is substantially composed of 1-chloro-3,3,3-trifluoropropene and a polyol ester synthesized from pentaerythritol.

[0146] 10. Use of the foregoing or subsequent embodiments / features / aspects, wherein the heat transfer composition exchanges heat with another heat transfer composition, said other heat transfer composition preferably contained in a vapor compression circuit.

[0147] 11. Use of the foregoing or subsequent embodiments / features / aspects for cooling equipment.

[0148] 12. Use of the foregoing or subsequent embodiments / features / aspects, wherein the temperature of the equipment is regulated by placing the equipment in direct contact with the heat transfer composition, preferably by immersing the equipment in the heat transfer composition.

[0149] 13. Use of the foregoing or subsequent embodiments / features / aspects, wherein the device is a battery for an electric or hybrid vehicle.

[0150] 14. The use of the foregoing or subsequent embodiments / features / aspects is carried out during the charging of the vehicle's battery, wherein the vehicle's battery is preferably fully charged within a time of less than or equal to 30 minutes and more preferably less than or equal to 15 minutes from the time it is fully discharged.

[0151] Example

[0152] Example 1 - Miscibility and Dielectric Properties

[0153] By using HCFO-1233zdE as a refrigerant with a mixture of benzyltoluene and dibenzyltoluene (produced by Arkema under the name Jarylec) ® The two products (C101 sales) were combined to prepare the composition. First, it was verified that the two products were miscible in all proportions.

[0154] Oil is introduced into a 0.34 L autoclave equipped with a magnetic stirrer and a jacket by weighing, and the heat transfer fluid flows in the jacket to homogenize the temperature in the gas and liquid phases.

[0155] The autoclave was then cooled to -10°C, and a vacuum was drawn at that point.

[0156] By weighing, HCFO-1233zdE contained in the cylinder is transferred as a liquid phase in a closed-loop mode.

[0157] Calculate the minimum liquid volume to be introduced such that the composition of the liquid phase does not change with temperature.

[0158] The final mixture is brought to the desired temperature under stirring to homogenize it. Stirring is then stopped until the mixture reaches equilibrium. Temperature and pressure are recorded at equilibrium.

[0159] Figure 1 The effect of refrigerant content on the liquid saturation temperature of the composition at a saturated vapor pressure of 1 bar is shown. More specifically, it can be seen that, relative to a composition containing 100% oil, adding refrigerant to the composition, even at a low content, significantly reduces the liquid saturation temperature of the composition, thereby increasing its ability to cool the battery.

[0160] By combining 69.2 g of HCFO-1233zd E and 100.5 g of Jarylec from Arkema under the conditions shown below ® The composition was prepared by mixing C101.

[0161] [Table 1]

[0162]

[0163] By combining 35 wt% HCFO-1233zdE and 65 wt% Jarylec from Arkema under the conditions shown below ® C101 is mixed to prepare another composition.

[0164] The breakdown voltage was measured according to standard IEC 60159:1995.

[0165] [Table 2]

[0166]

[0167] Example 2 - Viscosity

[0168] Viscosity measurements were performed in a jacketed autoclave reactor with a capacity of 0.2 L, in which a heat transfer fluid flowed. Oil (Jarylec) was introduced into the reactor. ® C101. Cool the reactor to -10°C and stir magnetically. Then introduce HCFO-1233zdE through a pressure differential. Then bring the reactor to the measured temperature.

[0169] The viscosity was then measured using a Sofraser MIVI 9601 vibrating rod viscometer. Before measurement, the miscibility of the oil and refrigerant under the measurement conditions was confirmed using a camera, and the immersion of the viscometer rod was checked.

[0170] [Table 3]

[0171]

[0172] For comparative purposes, the viscosity of the oil (0% HCFO-1233zd E) was measured at 20°C according to standard ISO 3104. The obtained value was 6.5 cP.

[0173] Example 3 - Flammability

[0174] For those containing 90% Jarylec ® A composition of C101 oil and 10% by weight of HCFO-1233zdE, and containing 100% by weight of Jarylec ® Flash point measurements were performed on a comparative composition of C101 oil.

[0175] The mixture is prepared at low temperature and atmospheric pressure. It is homogeneous and liquid at ambient temperature and atmospheric pressure.

[0176] Flash point measurements are performed according to standard ISO 3679 or ISO 3680, “Flash / no-flash type flash point test - rapid closed cup equilibrium method”. The standardized test is conducted with the filling port open and breathing into the atmosphere, while the cup is closed.

[0177] By sealing the filling port, the test is adjusted based on specific circumstances to simulate even more constrained devices during temperature equilibration (2 minutes under standardized conditions). In this case, the test is conducted with the device "sealed".

[0178] The temperature range explored is up to 300°C.

[0179] [Table 4]

[0180]

[0181] Example 4 - Heat Transfer Coefficient (Two-Phase Immersion)

[0182] To measure the heat transfer coefficient, a test apparatus placed in a heat-conditioning chamber is used to measure the fluid's performance by varying the ambient temperature. The test apparatus consists of a container equipped with a heating element and a condenser. The condenser is located at the top of the container and is cooled by a loop of ice-cold water. The heating element is a cylindrical resistor with a diameter of 15 mm and a height of 80 mm in a copper sheath, which is vertically immersed in a cylinder filled with a saturated liquid to heat it. It can provide up to 15 W / cm². 2 Eight temperature sensors were placed on the copper sheath to measure the surface temperature.

[0183] For oils (whose properties, especially viscosity, are similar to Jarylec) ® The viscosity of C101 oil, and its properties, especially its thermal properties (thermal conductivity greater than 0.05 W / (m)). 2 Two different mixtures of HCFO-1233zdE (with dielectric properties conforming to the specifications for this application) and K were tested. HCFO-1233zdE was introduced first, while avoiding any introduction of moisture or airborne contaminants. Oil was added by gravity using a graduated cylinder. Miscibility and homogeneity were checked by sampling.

[0184] Set the cooling water temperature (10°C at the condenser) and flow rate to the desired values. Set the ambient temperature to 26°C. Increase the heat power from 0 to 90 W in 5 W increments, then decrease it again to detect hysteresis. Measure the average heat transfer coefficient during the temperature rise: H = F / (T w -T sat ), where F is the heat flux density, T w It is the wall temperature, and T sat It is the liquid saturation temperature of the measured composition.

[0185] [Table 5]

[0186]

[0187] Example 5 - Heat Transfer Coefficient (Single-Phase Immersion)

[0188] For comparative heat transfer coefficient measurements, a test setup was used, comprising a module of 36 prismatic cell units (one actual lithium titanate cell surrounded by 35 dummy cells) within a sealed housing. The cell units and busbar were immersed in a liquid circulating at rates from 0.5 L / min to 40 L / min. Liquid inlet and outlet temperatures, flow rates, and pressures were measured and monitored. The liquid was externally cooled.

[0189] The individual cells are cooled on their small surfaces. Liquid channels are arranged in parallel. The module is equipped with 26 temperature sensors, eight of which are distributed on a large surface of the actual individual cells.

[0190] Tests at 0 and 1 W / cm 2 The process is conducted under different heat flux densities F. F is equal to the total supplied heat power divided by the total exchange area.

[0191] The tested liquid or its viscosity is similar to Jarylec ® Use an oil with a similar viscosity to C101, or a mixture of that oil and HCFO-1233zdE. First, introduce HCFO-1233zdE while avoiding any introduction of moisture or airborne contaminants. Add the oil by gravity using a graduated cylinder. Check miscibility and homogeneity by taking a sample.

[0192] The device was used in automatic testing mode, with a heat flux density F of 0.25 W / cm². 2 (Adjusted by changing the supplied power), and the average fluid temperature is 15°C (the average of the liquid temperature at the casing inlet and the liquid temperature at the casing outlet). For a given heat flux density, the liquid flow rate is increased to the maximum pumping speed, depending on the fluid.

[0193] The heat transfer coefficient H corresponds to the heat flux density divided by the difference between the average cell temperature and the fluid temperature at the inlet of the casing.

[0194] [Table 6]

[0195]

[0196] The maximum achievable liquid flow rate is 15 L / min with pure oil. The maximum achievable liquid flow rate is 18 L / min with a composition containing 10% HCFO-1233zdE.

Claims

1. Use of a heat transfer composition for regulating the temperature of electronic components, said heat transfer composition comprising at least one refrigerant selected from halogenated hydrocarbons, perhalogenated hydrocarbons, fluorinated ketones, fluorinated ethers, and combinations thereof, and at least one dielectric fluid, said heat transfer composition having a temperature at 25°C greater than or equal to 10 6 Volume resistivity in Ω·cm.

2. The use as described in claim 1, wherein the refrigerant comprises or is 1-chloro-3,3,3-trifluoropropylene, preferably in the E form.

3. The use as described in claim 1 or 2, wherein the refrigerant is present in an amount of 10% to 80% by weight, preferably 10% to 60% by weight, and even more preferably 10% to 40% by weight, relative to the total weight of the heat transfer composition.

4. The use as described in any of the preceding claims, wherein the dielectric fluid is selected from mineral dielectric oil, synthetic dielectric oil and vegetable dielectric oil; the synthetic fluid is preferably selected from alkylbenzene, alkyl diphenyl ethane, alkyl naphthalene, methyl polyarylmethane and aromatic hydrocarbons combined therewith; the dielectric fluid is more preferably a mixture of benzyltoluene and dibenzyltoluene.

5. The use as described in any of the preceding claims, wherein the dielectric fluid is present in an amount of 20% to 90% by weight, preferably 40% to 90% by weight, more preferably 40% to 60% by weight, relative to the total weight of the heat transfer composition.

6. The use as described in any of the preceding claims, wherein the heat transfer composition has a liquid saturation temperature of 20 to 80°C, and preferably 30 to 70°C, at a pressure of 1 bar.

7. The use as described in any of the preceding claims, wherein the heat transfer composition has a breakdown voltage of greater than or equal to 20 kV at 20°C.

8. The use as described in any of the preceding claims, wherein the heat transfer composition comprises essentially the following: 1-chloro-3,3,3-trifluoropropene; and a mixture of monobenzyltoluene and dibenzyltoluene.

9. The use as described in any of the preceding claims, wherein the heat transfer composition is substantially composed of 1-chloro-3,3,3-trifluoropropene and a polyol ester synthesized from pentaerythritol.

10. The use as described in any of the preceding claims, wherein the heat transfer composition exchanges heat with another heat transfer composition, which is preferably contained in a vapor compression circuit.

11. The use as described in any of the preceding claims, for cooling equipment.

12. The use as described in any of the preceding claims, wherein the temperature of the device is regulated by placing the device in direct contact with the heat transfer composition, preferably by immersing the device in the heat transfer composition.

13. The use as described in any of the preceding claims, wherein the device is a battery for an electric or hybrid vehicle.

14. The use as described in the preceding claims is carried out during the charging of the vehicle's battery, wherein the vehicle's battery is preferably fully charged within a time of less than or equal to 30 minutes and more preferably less than or equal to 15 minutes from the time it is fully discharged.

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