Battery thermal and safety management method and apparatus for carrying out said method

Abstract

The present invention relates to a thermal and safety management method for a battery in a device comprising a battery including a plurality of modules each including a plurality of cells, and a cooling circuit comprising a loop for circulating a coolant and a control valve for controlling the flow of the coolant upstream of each of the modules, the method comprising the steps of: a) detecting a failure of at least one cell of the module; and b) regulating the flow, if a failure is detected, including increasing the flow of coolant in one or more modules including at least one failed cell.

Description

[Technical Field]

[0001] The present invention relates to the thermal and safety management of batteries containing several cells, especially for mobile or stationary applications. [Background technology]

[0002] A battery is a system for generating electricity that converts chemical energy into electrical energy. The chemical energy consists of electrochemically active compounds deposited on at least one surface of electrodes arranged in an electrochemical generator. Electrical energy is produced by electrochemical reactions during discharge of the electrochemical cell.

[0003] A battery comprises a plurality of electrochemical cells. Lithium-ion electrochemical cells are based on the principle that lithium is reversibly inserted into a host structure in an electrochemically active manner.

[0004] In the field of electrochemical cells, such as Li-ion cells, the temperature of the cell must be controlled to maintain it within a suitable range.

[0005] Lithium-ion batteries are typically used at temperatures ranging from 0 to 40°C. In the event of a runaway, some cells can reach temperatures of around 400 to 800°C.

[0006] Batteries are commonly used in mobile or stationary applications.

[0007] Stationary applications include batteries for storing energy, such as solar storage batteries and energy storage systems.

[0008] Mobile applications include automotive applications such as electric vehicles or aviation.

[0009] Batteries are likely to generate a lot of heat, especially during fast charging. Therefore, it is necessary to be able to extract the heat. Air and water, optionally combined with antifreeze, are known methods for cooling batteries. However, with the advent of increasingly complex battery and heat-generating systems, cooling methods are not always sufficient.

[0010] Furthermore, one of the risks demonstrated in battery pack systems containing multiple cells is the propagation of a fault that can occur in one or more electrochemical cells that make up a battery, typically containing 100 to 10,000 cells. Such a fault can have various causes (short circuit, high temperature (e.g., above 150°C), loss of cell integrity during an accident, etc.), but it results in a very rapid increase in cell temperature (which can reach 800°C or more), accompanied by the emission of hot gases. Naturally, safety systems are implemented to prevent such potential faults. In this context, it is appropriate to consider the case where a fault has occurred. In this case, the safety system's purpose is to prevent the propagation of thermal runaway. In fact, the intense heat generated by a faulty cell can be the source of thermal runaway in adjacent cells.

[0011] The document EP 2 873 541 A1 discloses a cooling system for a battery of a hybrid or electric vehicle, which includes a circulation of a heat transfer coolant in a main loop and branches controlled according to the temperature of the heat transfer fluid. The document describes a relatively complex system including branch circuits. The document does not address the same problem as the present invention.

[0012] The document WO 2021 / 062305 discloses a technique for thermal management of the passenger compartment of a vehicle. The document is not aimed at a thermal management and safety system for the battery, and the document proposes circulating a coolant when the system exceeds a certain threshold.

[0013] Document EP 4027435 discloses that the system prevents the propagation of flames within the battery by circulating coolant when a certain threshold is exceeded. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] European Patent Application Publication No. 2873541 [Patent Document 2] International Publication No. 2021 / 062305 Brochure [Patent Document 3] European Patent Application Publication No. 4027435 Summary of the Invention [Problem to be solved by the invention]

[0015] The subject of the present invention is therefore to propose a novel battery thermal management safety control system that is easy to implement and aims at preventing the propagation of thermal runaway in faulty cells. [Means for solving the problem]

[0016] More precisely, the invention relates to a method for the thermal and safety management of a battery in a device comprising a battery including a number of modules each including a number of cells, and a cooling circuit comprising a circulation loop for a coolant and a regulating valve for regulating the flow rate of said coolant upstream of each of the modules, comprising: a) detecting a failure of at least one cell of a module; b) if a fault is detected, adjusting the flow rate includes increasing the coolant flow rate through the module(s) containing the at least one faulty cell.

[0017] According to one embodiment, at least 50% of the coolant flow rate is diverted to one or more modules containing at least one failed cell, preferably at least 70% of the flow rate, further preferably at least 90% of the flow rate or 100% of the coolant flow rate is directed to one or more modules containing at least one failed cell.

[0018] According to one embodiment, step a) comprises: a1 setting a threshold value for at least one parameter selected from temperature, voltage, and current; a2 measuring at least one parameter selected from temperature, voltage and current during battery operation; a3. Detecting a fault if the measured parameter is higher or lower than the threshold set during step a1.

[0019] According to one embodiment, the parameter is the temperature of the coolant, and the method comprises the steps of: a1 setting a temperature threshold that should not be exceeded; a2 measuring the coolant temperature at each outlet of the module or each outlet of the cell; a3 detecting a failure of at least one given module or cell when the temperature measured at the outlet of said module or cell exceeds a temperature threshold; b) diverting at least a portion of the coolant flow toward the failed module or the module containing the failed cell.

[0020] According to one embodiment, the parameter is the temperature of each of the modules or of each of the cells, and said method comprises the steps of: a1. setting a temperature threshold for each of the modules or cells that should not be exceeded; a2 measuring the temperature of each of the modules of the cell; a3. detecting a failure of at least one given module or cell when the measured temperature of said module or cell exceeds a temperature threshold; b) diverting at least a portion of the coolant flow toward the failed module or the module containing the failed cell.

[0021] According to one embodiment, step a) comprises: a1. setting a threshold for changing at least one parameter selected from temperature, voltage and current during a given time period; a2 measuring said parameters during battery operation; a3 detecting a failure of at least one given module or at least one given cell when said threshold is exceeded.

[0022] According to one embodiment, step b) further comprises reducing the flow rate of the coolant in one or more modules that do not have a failed cell.

[0023] According to one embodiment, the adjustment step b) is performed until the faulty cell or cells return to rated operation.

[0024] A further subject of the invention is an apparatus for carrying out the method according to the invention, comprising: - a battery including a plurality of modules each including a plurality of electrochemical cells; a cooling system, - a circulation loop for the coolant; - at least one valve upstream of each of the modules for controlling the flow of coolant; and a cooling system comprising:

[0025] According to one embodiment, said at least one valve is a shut-off valve that serves to stop the circulation of fluid in modules that do not contain any faulty cell(s).

[0026] According to one embodiment, the apparatus further comprises a control unit for detecting at least one faulty cell.

[0027] According to one embodiment, the device further comprises at least one sensor at the outlet of each of the modules or of each of the cells, allowing measurement of at least one parameter chosen from the temperature and the current of the coolant.

[0028] According to one embodiment, the device further comprises an air conditioning circuit through which a refrigerant fluid flows.

[0029] Preferably, the device comprises a refrigeration circuit further comprising at least one heat exchanger intended to exchange heat with the air or with the refrigerant fluid of the air conditioning circuit.

[0030] According to one embodiment, the device comprises a cooling circuit further comprising at least one heat exchanger intended to exchange heat with the air.

[0031] The management method of the present invention makes it possible to prevent the risk of thermal runaway and to reduce the propagation of thermal runaway very quickly.

[0032] The management method of the present invention is easy to implement and can be implemented in mobile or stationary applications.

[0033] The management method of the present invention does not require any external coolant supply, but rather uses the coolant already present in the circuit for cooling the battery to prevent the propagation of thermal runaway.

[0034] Thus, the method of the present invention can be used in batteries for storing energy, such as solar storage batteries and energy storage systems.

[0035] Thus, the method of the present invention can be used in electric or hybrid vehicles or aviation.

[0036] Unless otherwise indicated, amounts of product are expressed by weight relative to the total weight of the product. [Brief explanation of the drawings]

[0037] [Figure 1] FIG. 10 is a diagram showing the tendency of the oil pump flow rate in a reference case. [Figure 2] FIG. 10 illustrates the flow rate of coolant in a module and in a parallel module during a runaway. [Figure 3] FIG. 10 illustrates the trend of coolant temperature at different positions of the battery in the reference case. [Figure 4] FIG. 10 is a diagram showing the temperature trend of the cells in the module during runaway in the reference case. [Figure 5] FIG. 10 illustrates the flow distribution trends between runaway and parallel modules for different levels of flow regulation within the module. [Figure 6] FIG. 10 illustrates the trend of oil pump flow rate in a module during runaway for different levels of flow regulation in the module. [Figure 7] FIG. 10 illustrates the trend of oil temperature at the input of the battery pack for different levels of flow regulation within the module. [Figure 8] FIG. 10 shows the trend of oil temperature at the outlet of the module during runaway for different levels of flow regulation within the module. [Figure 9] FIG. 10 illustrates the trend of oil temperature at the outlet of the battery pack for different levels of flow regulation within the module. [Figure 10] FIG. 10 shows the temperature trends of cells adjacent to a runaway cell for different levels of flow regulation within a module. [Figure 11] FIG. 10 shows the trend of cell temperature during runaway for different levels of flow regulation within the module. DETAILED DESCRIPTION OF THE INVENTION

[0038] The present invention relates to a method for the thermal and safety management of a battery in a device comprising a battery and a cooling circuit.

[0039] In accordance with the present invention, a battery includes a plurality of modules, each containing a plurality of electrochemical cells.

[0040] Preferably, the modules of the battery are arranged in parallel with each other.

[0041] The thermal and safety management method according to the invention is generally carried out using a cooling circuit comprising a circulation loop for a coolant, said coolant being in direct contact with the cells.

[0042] Thus, according to one embodiment, the coolant is in direct contact with the cells. Indeed, the non-aqueous nature of the coolant allows direct contact to take place so that cooling and heat transfer is more efficient, whereas an aqueous coolant would not be able to come into direct contact and would therefore be less efficient in terms of cooling and heat transfer.

[0043] According to the invention, it is understood that the coolant and the cells come into contact by direct contact without any intervening obstacles, thereby optimizing the exchange surface between the coolant and the cells and achieving a better heat transfer efficiency, which prevents or delays the phenomenon of thermal runaway.

[0044] During rated operation, coolant circulates through each of the battery's modules at a given flow rate, preferably the same flow rate.

[0045] The coolant used according to the invention is preferably a non-aqueous coolant. The coolant used according to the invention advantageously has insulating properties, for example a resistivity at 30°C measured according to standard ASTM D1169 of 1 Mohm.m or more, preferably 100 Mohm.m or more. Thus, in general, the coolant used according to the invention has a resistance of 10 Mohm.m or more, preferably 100 Mohm.m or more. -6 ohm -1 .m -1 Below 10, preferably-8 ohm -1 .m -1 The electrical conductivity is: This property is particularly advantageous when a coolant is used in direct contact with the cells.

[0046] The coolant used in the present invention preferably comprises one or more base oils in a total content ranging from 70 to 100% by weight, preferably from 70 to 99% by weight, further preferably from 80 to 98% by weight, and suitably from 85 to 95% by weight, relative to the total weight of the coolant composition.

[0047] According to one embodiment, the refrigerant comprises 100% by weight of base oil(s) based on the total weight of the refrigerant.

[0048] Such base oils may be selected from base oils conventionally used in the field of lubricating oils, such as mineral oils, synthetic or natural oils, animal oils or vegetable oils, or mixtures thereof.

[0049] Mixtures of more than one base oil may also be present, for example mixtures of two, three or four base oils.

[0050] More particularly, the base oil used in the refrigerant used in the present invention may be a mineral or synthetic oil belonging to Groups I to V according to the classes defined by the API classification shown in Table 1 below (or their equivalents according to the ATIEL classification), or a mixture thereof. [Table 1]

[0051] Mineral base oils include any type of base oil obtained by carrying out atmospheric and vacuum distillation of crude oil, followed by refining operations such as solvent extraction, deasphalting, solvent dewaxing, hydrotreating, hydrocracking, hydroisomerization and hydrofinishing.

[0052] Additionally, mixtures of synthetic and mineral oils, which may be bio-based or recyclable, may also be used.

[0053] The base oil of the coolant according to the invention may further be selected from synthetic oils such as certain carboxylic acid esters and alcohol esters, polyalphaolefins (PAOs) and polyalkylene antifreeze agents (PAGs) obtained by polymerization or copolymerization of alkylene oxides containing from 2 to 8 carbon atoms, in particular from 2 to 4 carbon atoms.

[0054] PAOs used as base oils are derived, for example, from monomers containing 4 to 32 carbon atoms, such as octene or decene. The weight average molecular weight of PAOs varies widely. Preferably, the weight average molecular weight of the PAO is less than 600 Da. The weight average molecular weight of the PAO can also be in the range of 100 to 600 Da, 150 to 600 Da, or even 200 to 600 Da.

[0055] Additional additives may also be used in the coolants used in the present invention, including antioxidants, corrosion inhibitor-type additives, antifoam-type additives, and pour point depressants.

[0056] According to a particularly preferred embodiment, the cooling composition used in the present invention comprises at least one antioxidant-type additive. Antioxidant-type additives generally make it possible to retard the deterioration of the composition during use, the majority of which is usually manifested as the formation of deposits, the presence of sludge or an increase in the viscosity of the composition.

[0057] Antioxidant-type additives act in particular as radical inhibitors or hydroxide destroyers. Commonly used antioxidant-type additives include phenolic antioxidants, amine antioxidant-type additives, and phosphorus-sulfur-containing antioxidant-type additives.

[0058] The coolant used in the present invention may contain 0.1 to 2% by weight of at least one antioxidant type additive relative to the total weight of the coolant.

[0059] The coolant used in the present invention may contain at least one corrosion inhibitor type additive, which advantageously retards or prevents corrosion of the metal parts of the battery.

[0060] The coolant used in the present invention may contain 0.01 to 5% by weight, preferably 0.1 to 2% by weight, of a corrosion inhibitor based on the total weight of the coolant.

[0061] The coolant according to the invention may further comprise at least one antifoaming agent, which may be selected from polyacrylates, silicones, fluorinated compounds or waxes.

[0062] The coolant used in the present invention may contain 0.001 to 5% by weight, preferably 0.1 to 2% by weight, of an antifoaming agent relative to the total weight of the coolant.

[0063] The refrigerants used in the present invention may further comprise at least one pour point depressant (PPD) type additive. Pour point depressant type additives generally improve the behavior of the composition under low temperature conditions by slowing the formation of paraffin crystals. Examples of pour point depressant type additives include alkyl polymethacrylates, polyacrylates, polyarylamides, polyalkylphenols, polyalkylnaphthalenes, and alkyl polystyrenes.

[0064] The coolant used in the present invention may further comprise one or more fluorocarbon compounds, including perfluorooctyl bromide.

[0065] The coolant used in the present invention may contain 0.01 to 10%, preferably 0.1 to 5% by weight, advantageously 0.5 to 2% by weight of fluorocarbon compounds relative to the total weight of the coolant.

[0066] The coolant according to the invention may further comprise at least one antiwear agent. According to one embodiment, the antiwear agent is selected from phosphorus-containing antiwear agents, phosphorus-sulfur-containing antiwear agents, phosphorus-amine-containing antiwear agents and mixtures thereof, preferably from phosphorus-containing antiwear agents.

[0067] According to one embodiment, the antiwear agent is a phosphite polymer, preferably represented by formula (I): [ka] (In the formula, -R 1 , R 2 , R 3 and R 4 Each of these is independent of each other, C1 to C 20 Alkyl moiety, C3-C 22 Alkenyl moiety, C6-C 40 Cycloalkyl moiety, C7-C 40 Cycloalkenyl moiety, C 1~20 May be selected from methoxyalkyl glycol ethers and Y-OH; - Y is C2~C 40 Alkylene moiety, C2-C 40 Alkyl lactone moiety, -R 7 -N(R 8 )-R 9 wherein R is selected from 7 , R 8 and R 9 are each independently hydrogen, C1 to C 20 Alkyl, C3-C 22 Alkenyl, C6-C 40 Cycloalkyl, C7-C 40 Cycloalkenyl, C1~ 20 methoxyalkyl glycol ethers; m is an integer from 2 to 100; - n is an integer from 1 to 1000 is a phosphite polymer corresponding to

[0068] According to one embodiment, the phosphite polymer preferably corresponding to formula (I) has a weight average molecular weight of less than 30,000 g / mol, preferably in the range of 3000 to 20,000 g / mol, which can be measured by steric exclusion chromatography.

[0069] According to one embodiment, the phosphite polymer preferably corresponding to formula (I) has a number average molecular weight of less than 10,000 g / mol, preferably in the range of 1000 to 5000 g / mol, which can be measured by size exclusion chromatography.

[0070] According to one embodiment, the phosphite polymer, preferably corresponding to formula (I), has a polydispersity index in the range of 1-5, preferably in the range of 2-4.

[0071] The phosphite polymers that can be used in the present invention can be obtained by the method described in document WO 2011102861. More particularly, the polymers can be obtained by the method described in paragraphs 27 to 32 of said document.

[0072] According to one embodiment, the antiwear type additive is chosen from phosphorus-sulphur containing additives such as metal alkylthiophosphates, more particularly zinc alkylthiophosphates, more precisely zinc dialkyldithiophosphates or ZnDTP. Preferred compounds have the formula Zn((SP(S)(OQ 2 )(OQ 3 ))2 (wherein the same or different QR 2 and Q 3 independently represent an alkyl moiety, preferably an alkyl moiety containing 1 to 18 carbon atoms.

[0073] Examples include phosphorus-sulfur-containing antiwear additives, monobutyl thiophosphate, monooctyl thiophosphate, monolauryl thiophosphate, dibutyl thiophosphate, dilauryl thiophosphate, tributyl thiophosphate, trioctyl thiophosphate, triphenyl thiophosphate, monooctyl thiophosphite, trilauryl thiophosphate, monolauryl thiophosphite, monobutyl thiophosphite, dibutyl thiophosphite, dilauryl thiophosphite, tributyl thiophosphite, trioctyl thiophosphite, triphenyl thiophosphite, trilauryl thiophosphite, and salts thereof.

[0074] Similarly, amine phosphates are also anti-wear type additives that can be used in coolants according to the present invention. However, the phosphorus provided by such additives can act as a poison in catalyst systems due to the generation of ash. This effect can be minimized by partially replacing the amine phosphates with additives that do not provide phosphorus, such as polysulfides, especially sulfur-containing olefins.

[0075] The coolant used in the present invention may contain 0.01 to 15%, preferably 0.1 to 10% by weight, and suitably 1 to 5% by weight of anti-wear agent(s) relative to the total weight of the composition.

[0076] The additives can be introduced individually and / or in the form of a mixture of additives by methods well known to those skilled in the art.

[0077] Advantageously, the coolant used in the present invention has a thickness of between 1.5 and 35 mm, measured at 40°C according to standard ASTM D445. 2 / s range, more specifically 2-25mm 2 / s range, and even 2.5 to 10 mm 2 / s range of kinematic viscosity.

[0078] Advantageously, the coolant used in the invention has a thickness of between 0.5 and 7 mm, measured at 100°C according to standard ASTM D445. 2 / s range, more specifically 1-4 mm 2 / s range, and even 1.1 to 2.5 mm 2 / s range of kinematic viscosity.

[0079] Alternatively, the refrigerant used in the present invention may consist solely of at least one mineral or synthetic base oil, possibly bio-based or recycled.

[0080] The thermal management and safety management method according to the present invention comprises: a) detecting a failure of at least one electrochemical cell of at least one module of the battery; b) if a fault is detected, increasing the flow rate of coolant through the module(s) containing the at least one faulty cell.

[0081] According to one embodiment, a cell is deemed to be faulty if at least one parameter selected from temperature and current is above or below a given threshold.

[0082] In the framework of the present invention, a module is considered to be faulty if it contains at least one faulty cell.

[0083] Thus, generally, if no fault is detected, the flow rate of coolant through the battery module is not altered.

[0084] According to one embodiment, step a) comprises: a1) setting a threshold value for at least one parameter selected from temperature, voltage, and current; a2) measuring said at least one parameter selected from temperature, voltage and current during battery operation, wherein the measuring step may be performed continuously or sequentially; a3) comparing said at least one measured parameter with said threshold value; a4) detecting a fault if the measured parameter is higher or lower than the threshold set during step a1.

[0085] According to one embodiment, the parameter is the respective temperature of the modules, and step a) of the method according to the invention preferably comprises the steps of: a1) setting a temperature threshold T1 that should not be exceeded; a2) measuring the temperature T2 of each of the modules; a3) comparing the measured temperature with a temperature threshold; a4) detecting a failure of a given module when the measured temperature of said module exceeds the threshold temperature value determined during step a1 (when T2>T1).

[0086] According to one embodiment, the parameter is the respective temperature of the cells, and step a) of the method according to the invention preferably comprises: a1) setting a temperature threshold T1 that should not be exceeded; a2) measuring the temperature T2 of each of the cells; a3) comparing the measured temperature with a temperature threshold; a4) detecting a failure of a given cell when the measured temperature of said cell exceeds the threshold temperature value determined during step a1 (when T2>T1).

[0087] According to one embodiment, the parameter is the temperature of the coolant at the outlet of each of the modules, and step a) of the method according to the invention preferably comprises: a1) setting a temperature threshold T1 that should not be exceeded; a2) measuring the temperature T2 of the coolant at the outlet of each of the modules; a3) comparing the measured temperature with a temperature threshold; a4) detecting a failure of a given module when the temperature measured at the outlet of said module exceeds the temperature threshold determined during step a1 (when T2>T1).

[0088] According to one embodiment, the parameter is the temperature of the coolant at the outlet of each of the cells, and step a) of the method according to the invention preferably comprises: a1) setting a temperature threshold T1 that should not be exceeded; a2) measuring the temperature T2 of the coolant at the outlet of each of the cells; a3) comparing the measured temperature with a temperature threshold; a4) detecting a failure of a given cell when the temperature measured at the outlet of said cell exceeds the threshold temperature value determined during step a1 (when T2>T1).

[0089] According to one embodiment, step a) comprises: a1) setting a threshold for changing at least one parameter selected from temperature, voltage and current during a predetermined time; a2) measuring said at least one parameter selected from temperature, voltage and current during battery operation, which may be performed continuously or sequentially; a3) detecting a fault when the threshold set during step a1 is reached.

[0090] According to such an embodiment, a fault is detected when a parameter changes too rapidly, and therefore a threshold value for said parameter can be set such that said value is considered to have been reached if the parameter changes too rapidly over a given predetermined time period.

[0091] If the parameter is temperature, the threshold may be the change in said temperature over a given period of time, so that if the temperature changes very rapidly (i.e. with a certain amplitude over a given time), this may be considered as a sign that the cell is failing.

[0092] As a non-limiting example, if the temperature of the coolant at the outlet of a module or cell changes by at least 20°C, or at least 10°C, or at least 5°C over a given period of time, for example 10 seconds, then the cell can be considered to have failed or the module can be considered to have failed (or contain at least one failed cell).

[0093] As a non-limiting example, if the temperature of a module or cell changes by at least 20°C, or at least 10°C, or at least 5°C over a given period of time, e.g., 10 seconds, the module can be considered to be faulty (or contain at least one faulty cell).

[0094] According to one embodiment, the parameter is voltage and cell failure is detected when the voltage of said cell reaches 0 V. According to such an embodiment, the threshold value of the parameter is 0 V.

[0095] According to one embodiment, a fault is detected when the voltage drops too quickly.

[0096] As a non-limiting example, if the voltage of at least one cell changes by at least 3V, or at least 2V, or at least 1V over a predetermined period of time, for example 10 seconds, then said cell may be considered to have failed.

[0097] Voltage is an easy to determine and clear indicator of battery, cell or module fault / failure.

[0098] Generally, each module has an inlet for adding coolant into the module and an outlet for withdrawing coolant from the module.

[0099] According to one embodiment, each of the modules comprises a flow path, called a coolant flow path, which allows the coolant to circulate within the module over all or part of the length of each of the cells within the module.

[0100] Measurements of a given parameter can be made continuously or sequentially at regular intervals.

[0101] According to one embodiment, step b) of adjusting at least a portion of the flow rate comprises increasing the flow rate of the coolant in one or more modules having at least one failed cell and decreasing the flow rate of the coolant in one or more modules not having the failed cell.

[0102] The flow regulation step b) is sometimes called a flow redirection step.

[0103] Therefore, according to the invention, the adjustment step b) is a flow redirection step.

[0104] According to the present invention, flow redirection means that at least a portion of the coolant circulating in one or more modules at a given flow rate during rated operation is redirected from one or more modules that do not have any failed cells to one or more modules that have at least one failed cell.

[0105] According to one embodiment, the flow rate can be adjusted during step b) using variable aperture valves, said valves being preferably located on the cooling circuit upstream of each of the modules.

[0106] According to one embodiment, the valve is a solenoid valve.

[0107] According to one embodiment of the thermal management and safety management method of the present invention, the flow rate adjustment step b) includes a step of closing at least one valve upstream of at least one module that does not have any faulty cell(s), preferably a step of closing each valve upstream of each module that does not have any faulty cell(s).

[0108] According to one embodiment, the valve is a shut-off valve that acts to stop the circulation of coolant in each of the modules that does not have any failed cell(s).

[0109] Thus, generally within the framework of the present invention, for a battery comprising a number X of modules (the modules being in parallel in a fluid sense) and operating with a total coolant flow rate D: During rated operation, each of the modules m receives D / X% of the total flow rate D, i.e. the coolant flow rate is distributed evenly to each of the modules of the battery. - if a fault is detected in at least one cell of one of the modules, said module with at least one faulty cell receives a flow rate greater than D / X%. In other words, the flow rate is no longer distributed uniformly, but is adjusted so that the total flow rate received by the faulty module is greater than the total flow rate received by each of the other non-faulty modules.

[0110] According to one embodiment of the management method of the present invention, the battery comprises at least three parallel modules, and at least 50% of the coolant flow is diverted to the module or modules containing at least one failed cell, preferably at least 70% of the flow, further preferably at least 90% of the flow or 100% of the coolant flow is diverted to the module or modules containing at least one failed cell.

[0111] According to one embodiment, 50% to 90% of the coolant flow is diverted to one or more modules having at least one failed cell, resulting in one or more modules that do not have one or more failed cells remaining in contact with the coolant.

[0112] According to one embodiment of the management method according to the invention, the adjustment step b) is carried out until the faulty cell or cells return to rated operation.

[0113] As defined by the present invention, cells with rated operation are hereinafter not considered to be faulty.

[0114] Preferably, the faulty cell is considered to be in rated operation when it has a temperature below 100° C., preferably below 50° C. Therefore, according to one embodiment of the management method according to the invention, step b) of adjusting the flow rate is carried out until the faulty cell or cells return to a temperature below 100° C., preferably below 50° C.

[0115] According to one embodiment, the thermal and safety management method is performed by an apparatus.

[0116] According to one embodiment, an apparatus for carrying out a thermal and safety management method comprises a temperature sensor for the coolant at the inlet of the battery and a temperature sensor for the coolant at the outlet of the battery.

[0117] According to one embodiment, the device for carrying out the thermal and safety management method comprises a temperature sensor for the coolant, which allows the determination of the temperature of the coolant at the outlet of each of the modules and / or each of the cells. Such an embodiment is particularly suitable when the determined parameter is the temperature of the coolant at the outlet of each of the modules and / or each of the cells.

[0118] According to one embodiment, the device for carrying out the thermal and safety management method comprises a temperature sensor for determining the temperature of each of the modules and / or each of the cells, such an embodiment being particularly suitable when the determined parameter is the temperature of each of the modules and / or each of the cells.

[0119] Thus, according to a particularly advantageous embodiment, the device comprises a battery and a cooling circuit, the battery comprising a plurality of modules, each of the modules comprising a plurality of cells, the cooling circuit comprising a circulation loop for a coolant and a control valve upstream of each of the modules for regulating the flow rate of said coolant, the coolant circulating at a given flow rate during rated operation and in direct contact with the cells, the thermal and safety management method of the invention advantageously comprises: a1) setting a threshold value for at least one parameter selected from temperature, voltage, and current; a2) measuring at least one parameter selected from temperature, voltage and current during battery operation; a3) detecting a fault when the measured parameter is higher or lower than the threshold value set during step a1; b) if a fault is detected, a flow redirection step including: (i) increasing the flow rate of coolant through the module(s) having at least one faulty cell; and (ii-1) decreasing the flow rate of coolant through the module(s) not having at least one faulty cell, or (ii-2) stopping the flow rate of coolant through the module(s) not having at least one faulty cell.

[0120] Thus, according to a particularly advantageous embodiment, the device comprises a battery including a number of modules each including a number of cells, and a cooling circuit comprising a circulation loop for a coolant and a control valve for regulating the flow rate of said coolant upstream of each of the modules, the coolant circulating at a given flow rate during rated operation and in direct contact with the cells, the thermal and safety management method of the invention advantageously comprising: a1) setting a temperature threshold for each of the modules or cells that should not be exceeded; a2) measuring the temperature of each of the modules or each of the cells; a3) detecting a failure of at least one given module or at least one given cell when the measured temperature of said module or said cell exceeds a temperature threshold; b) if a fault is detected, a flow redirection step including: (i) increasing the flow rate of coolant through the module(s) having at least one faulty cell; (ii-1) decreasing the flow rate of coolant through the module(s) not having at least one faulty cell; or (ii-2) stopping the flow rate of coolant through the module(s) not having at least one faulty cell.

[0121] A further subject of the invention is an apparatus, comprising: - a battery including a plurality of modules each including a plurality of electrochemical cells; a cooling system, - a circulation loop for the coolant; - at least one valve upstream of each of the modules for controlling the flow rate of the coolant; and a cooling system comprising:

[0122] According to one embodiment, the apparatus further comprises a control unit for detecting at least one faulty cell.

[0123] According to one embodiment, the device further comprises at least one sensor at the outlet of each of the modules for measuring at least one parameter chosen from temperature, voltage and current.

[0124] According to one embodiment, the device further comprises at least one heat exchanger intended to be connected to an air conditioning circuit through which a refrigerant fluid flows.

[0125] Thus, according to one particular embodiment of the invention, the device comprises: - a battery including a plurality of modules each including a plurality of electrochemical cells; - an exchanger, also called a radiator, for discharging part of the calories stored by the coolant into the outside air; a chiller (such as a plate heat exchanger) that allows the exchange of heat between the air or a separate coolant circuit (so-called "refrigerant" fluid) reserved for the air conditioning of the vehicle; - a heating system to increase the temperature of the coolant to warm the battery, if necessary, during a cold start or when the vehicle is operating in a cold atmosphere; - at least one pump; - a circulation loop for the coolant; a valve for activating the circuit and maintaining flow through the entire circuit.

[0126] The features and advantages specified for the management method according to the invention also apply to the device according to the invention.

[0127] According to one embodiment, the device according to the invention further comprises a temperature sensor for the coolant at the inlet of the battery and a temperature sensor for the coolant at the outlet of the battery.

[0128] According to one embodiment, the device according to the invention further comprises a temperature sensor for the coolant for determining the temperature of the coolant at the outlet of each of the modules and / or each of the cells, such an embodiment being particularly suitable when the determined parameter is the temperature of the coolant at the outlet of each of the modules and / or each of the cells.

[0129] According to one embodiment, the device according to the invention further comprises a temperature sensor for determining the temperature of each of the modules and / or each of the cells, such an embodiment being particularly suitable when the determined parameter is the temperature of each of the modules and / or each of the cells.

[0130] According to one embodiment, the device includes an air conditioning circuit in addition to the refrigeration circuit. Such an air conditioning circuit can exchange heat via a chiller in the refrigeration circuit and can further include a compressor, an expansion valve, and a condenser. The air conditioning circuit can circulate a refrigerant fluid, for example, a hydrofluoroolefin such as HFO-1234yf.

[0131] According to such an embodiment, heat exchange may be performed between the coolant and the refrigerant fluid by the chiller.

[0132] A compressor may be present in the air conditioning system, the function of which is to increase the pressure level of the refrigerant fluid in the gas phase at the outlet of the exchanger before it passes through the condenser to liquefy.

[0133] An expansion valve, such as an electronic expansion valve, may be present in the air conditioning system. Such a valve reduces the pressure and controls the flow rate of the refrigerant fluid at the outlet from the condenser to maximize the efficiency of the plate heat exchanger. In effect, the valve reduces the pressure of the refrigerant so as to allow an optimal amount of refrigerant to pass through, so that the refrigerant is under temperature and pressure conditions very close to vapor-liquid equilibrium and the phase change (made possible by the addition of heat provided by the refrigerant) is completed.

[0134] A condenser may be present in the air conditioning system, and such a condenser serves to convert the pressurized gas into a pressurized liquid at the outlet of the compressor.

[0135] The present invention can be used in electric vehicles to avoid thermal runaway of the battery. Therefore, the device according to the present invention can be used in electric vehicles and hybrid vehicles, especially rechargeable hybrid vehicles.

[0136] As defined by the present invention, an "electric vehicle" refers to a vehicle that has an electric motor as its sole propulsion means, whereas a hybrid vehicle has an internal combustion engine and an electric motor as its combined propulsion means.

[0137] The term "propulsion means" as defined by the present invention refers to a system comprising the mechanical components necessary for the propulsion of an electric vehicle. More specifically, the propulsion system therefore includes an electric motor with a rotor-stator assembly (dedicated to speed regulation), a power electronics system, a transmission, and a battery.

[0138] The device according to the invention may also be used in an energy storage assembly or an aircraft.

[0139] The present invention will now be described by way of the following examples, but it will be understood that these examples are given by way of illustration of the present invention and that the present invention is not limited to these examples. [Example]

[0140] To demonstrate the benefits of the management method of the present invention, a model was implemented using the software Simulation X.

[0141] The model consists of a battery pack containing 16 modules of 6 cells in an 8p2s configuration (two strings of 8 modules in parallel). The modelled cells are "pouch" cells with a height of 276 mm, a length of 176 mm and a thickness of 8 mm and a capacity of 40 Ah in NMC technology.

[0142] From a fluid dynamics point of view, the heat transfer fluid (coolant) therefore circulates in fluid channels of rectangular area (276 mm high and 2 mm wide) over the entire length of the cells (176 mm). Two buffer areas at the inlet and outlet of the module ensure that the flow rate is uniformly distributed between each of the fluid channels. The aforementioned buffer areas have a thickness of 5 mm, a height of 276 mm and a width equivalent to six cells and six fluid channels, i.e., a width of 60 mm.

[0143] From a system modeling perspective, a 3D configuration was approximated using fluid volumes (two volumes corresponding to the buffer zone and six volumes corresponding to the fluid flow paths) and pipes of rectangular cross section to calculate the pressure drop caused by the circulation of the coolant.

[0144] The cells are of the same size (as above), density (2700 kg.m -3 ) and specific heat capacity (900J.kg -1 .K -1 ) is expressed by the solid heat capacity parameterized by

[0145] Furthermore, as can be seen in Figure 4, each of the cells is connected to a controllable heat source, leaving the possibility to explore rated operation or thermal runaway configurations as required.

[0146] To complete the system model of the module, the thermal-fluid coupling, i.e., the heat transfer between the cells (solid heat capacity) and the coolant (fluid volume), was performed using a function expressing the heat transfer coefficient as a function of the average velocity of the flow in the fluid channels calculated from the 3D simulation (see Figure 5).

[0147] In the selected configuration (8p2s), the choice was made to cause a runaway in one of the cells of one of the modules belonging to the first row. Such a configuration has a higher criticality insofar as the coolant leaving the runaway module must pass through a module belonging to the second row.

[0148] If we assume that the coolant supplied to all modules is equalized upstream and downstream of the modules (for example, by a manifold), the configuration can be simplified digitally by considering that all modules belonging to the same row that are not directly in runaway behave exactly the same.

[0149] The pump chosen for this study is a positive displacement pump, which has the advantage of operating at a high level of efficiency. The pump is speed controlled, providing a variable flow rate depending on the pressure level (and therefore the head loss) present in the fluid circuit. The advantage of operating with constant speed control is that it allows quantifying the efficiency of the regulation of the flow distribution by taking into account the possible head loss increase.

[0150] Valves are useful elements for regulating the flow between different modules, especially between the runaway module and other modules. In the model, variable aperture valves were used to tightly control the flow distribution.

[0151] For the module parallel to the runaway module, different opening levels were tested. - 100% corresponds to the case where each module receives an "equal" fraction of the flow rate (in reality, the flow rate increases very slightly within a module during a runaway due to the reduction in head losses caused by the heating of the coolant). - 30%, which corresponds to the case where slightly more than half of the coolant (57.3%) enters the runaway module - 10% corresponds to the case where the majority of the coolant (93.3%) passes through the runaway module and only a small amount of circulation is maintained in the parallel module. - 0% corresponding to the case where all flow delivered by the pump is diverted to the runaway module.

[0152] It should be noted that in all cases where the flow rate is adjusted to give priority to the runaway module, the adjustment is synchronized in time with the onset of the runaway.

[0153] The developed model includes three temperature probes and one pressure probe. The temperature sensors are used to measure the temperature of the coolant upstream of the battery pack at the outlet of the module during runaway and at the outlet of the battery pack. The pressure sensor is placed upstream of the pump to calculate the exact head loss of the system and adapt the pump flow rate.

[0154] The coolant used for the investigation is an oil with the following characteristics: - 0.7740 g / cm at 25°C 3 density of - 0.7650g / cm at 50℃ 3 density of - 0.7225g / cm at 100℃ 3 density of - 27mm at -25°C 2 / s kinematic viscosity - Approximately 9mm at 0℃ 2 / s kinematic viscosity - Approximately 3mm at 40℃ 2 / s kinematic viscosity - Approximately 1mm at 100℃ 2 / s kinematic viscosity - Thermal conductivity of approximately 0.1275 W / (mK) at 40°C - Thermal conductivity of approximately 0.1175W / (mK) at 80℃ - 2100J.kg -1 .K -1 Heat capacity of

[0155] The model further includes an air conditioning system with a plate heat exchanger (chiller), compressor, electronic expansion valve and condenser.

[0156] The plate heat exchanger allows for the cooling of the coolant in the battery circuit. The heat exchange occurs by a phase change (gas to liquid) of the refrigerant fluid (R1234yf). The exchanger has a height of 170 mm, a width of 80 mm and a thickness of 68 mm. Each plate has a thickness of 0.35 mm, and the exchanger has 0.78 plates per mm.

[0157] The function of the compressor is to increase the pressure level of the refrigerant fluid in vapor phase at the outlet of the exchanger before it passes through the condenser where it is liquefied.

[0158] For a given compressor geometry, the compression level can be directly controlled by adjusting the power consumption or rotational speed, and in the present model, it is this second parameter that is adapted by the control strategy to meet the coolant temperature setpoint at the battery pack inlet.

[0159] The set point temperature is 25°C during the steady state operation phase and 20°C after thermal runaway occurs until the end of the simulation.

[0160] It should be noted that restrictions are imposed on the reaction time and rotational speed thresholds in order to maintain the dynamic consistency of the compressor response, more particularly to prevent excessive increases in rotational speed after the coolant temperature rises during thermal runaway.

[0161] The influence of the maximum allowable rotational speed on the exchanger performance and flow regulation values was investigated in simulations using two values: 1250 rpm and 5000 rpm.

[0162] The electronic expansion valve reduces the pressure and controls the flow rate of the refrigerant fluid at the outlet from the condenser to maximize the efficiency of the plate heat exchanger. In fact, the valve must reduce the pressure of the refrigerant so as to allow the optimum amount of refrigerant to pass through, so that the refrigerant is at temperature and pressure conditions very close to vapor-liquid equilibrium and the phase change (made possible by the addition of heat provided by the refrigerant) is complete.

[0163] In the model, as in reality, the strength of decompression is controlled by a control strategy that varies the valve opening level to meet a 5°C setpoint during runaway of the refrigerant fluid at the exchanger outlet. Such a setpoint ensures that the entire refrigerant fluid has already undergone a phase change when the setpoint is reached. For the compressor, a threshold is imposed on the regulation of the valve opening level to prevent complete closure of the valve, which could cause convergence problems in the model, among other things.

[0164] As the name suggests, the function of the condenser is to convert the pressurized gas at the compressor outlet into pressurized liquid. To limit the number of variables in the model, all parameters controlling the operation of the condenser were fixed. The outside air temperature was set to 20°C, and the pump flow rate was set to 100 l / s. The condenser has a height of 590 mm, a width of 326 mm, and a thickness of 29 mm. The inner diameter of the tubes is 10 mm, and the tube wall thickness is 1 mm. There are 48 tubes per row.

[0165] (Out-of-control occurrence) Each calculation consists of a time simulation of the system's operation over a duration of 1 hour (3600 s) following the numerical protocol below. - At t=0s, a 20W heat source is applied to all cells of the battery pack to represent steady-state operating conditions. From t=0 s to t=1500 s, the control strategy implemented in the pilot air conditioning circuit increases the amount of heat absorbed by the plate heat exchanger and increases the compressor rotational speed in order to meet the 25°C temperature requirement imposed on the coolant at the battery pack inlet. - At t=1500s, once the system is fully stabilized (i.e., there are no transitions of the main variables resolved in the two circuits), a thermal runaway event is initiated by applying a dissipative heat power of 722.67 kW to one of the cells of the module belonging to the first row (cell number 2) for 10 seconds. The flow regulation is immediately activated (if tested) and the temperature setpoint of the coolant entering the battery pack is reduced from 25°C to 20°C. From t=1510s to t=3600s, no heat source is applied to the battery, leaving the control of the cooling fluid to the control strategy.

[0166] (Example 1: Reference Case) A reference configuration was simulated for comparison with the method of the present invention.

[0167] In the reference configuration, the flow rate is shared equally between each of the modules without any redirection.

[0168] The oil pump operates at a speed of 3000 rpm and the compressor has a rotational speed limit of 5000 rpm.

[0169] The results obtained for the reference case are shown in Figures 1 to 4.

[0170] Figure 1 shows that the oil pump flow rate remains relatively stable (approximately 22 l / min) throughout the simulation. Once runaway occurs (t=1500 s), some fluctuations can be seen. In the absence of regulation, these fluctuations are essentially caused by fluctuations in heat losses associated with changes in coolant temperature.

[0171] FIG. 2 shows that the coolant flow rate within the packaged module increases slightly at the onset of thermal runaway.

[0172] FIG. 3 shows that the coolant temperature at the outlet of the module containing the failed cell rises sharply, while the coolant temperature at the inlet and outlet of the battery remains relatively stable.

[0173] When a runaway occurs in one of the modules in the first string, power is removed from the cells (which were continuously dissipating 20 W of heat before the power was removed), causing the coolant temperature to drop slightly in all remaining modules. As a result, head loss increases slightly and flow rate decreases. Flow rate increases again briefly as the fluid recovers the heat generated by the thermal runaway cell, then decreases again as the fluid cools.

[0174] Figure 4 shows that the temperature of the cell adjacent to the failed cell (packaged cell) reaches 67°C. While such a temperature may seem relatively low and sufficient to prevent risk, it should be noted that the model does not take into account certain phenomena, such as the release of very high temperature gases that could adversely affect the situation and the narrowing of the coolant flow paths due to swelling of the packaged cell. Figure 4 shows that the failed cell reached a temperature of more than 750°C.

[0175] Therefore, the presented model is a good model for assessing the technical merits of the present invention.

[0176] Example 2: Flow Diversion (Adjustment) In this example, the results of three levels of adjustment (or redirection) are compared against a reference configuration (Example 1).

[0177] The strength of the adjustment is shown in FIG. 5 as the flow distribution between the packaged and parallel modules.

[0178] Therefore, four regulation configurations were tested, each corresponding to a ratio of coolant flow in the runaway module to the total flow. - 12.5% (reference case), - 57.3% (partial opening or partial accommodation), - 93.3% (minimal opening or near full accommodation) and - 100% (closed or fully adjusted).

[0179] FIG. 5 shows, for each regulation configuration, the flow rate in the module containing the runaway cell in the upper part of the graph and the flow rate in the parallel module in the lower part of the graph.

[0180] As can be seen in Figure 6, flow regulation results in a small change in the pump flow rate. The pump flow rate decreases as the flow rate increases in the runaway module. This decrease is explained by the increased head loss in the system.

[0181] FIG. 7 shows the trend in fluid temperature at the battery inlet for each of the four conditioning configurations.

[0182] FIG. 8 shows the trend in fluid temperature at the outlet of the module during runaway for each of the four regulation configurations.

[0183] FIG. 9 shows the trend in fluid temperature at the battery outlet for each of the four conditioning configurations.

[0184] As can be seen from a comparison of Figures 5 and 9, the head loss is primarily controlled by the speed increase (nonlinear dependence) of the module during runaway.

[0185] The reduction in the total flow rate in the circuit when performing the regulation is an important result, as it would be expected to be accompanied by a deterioration in the thermal management of the battery during runaway, however this is not observed in the cell temperatures of the module during runaway.

[0186] FIG. 10 shows the temperature trends of the cells adjacent to the runaway cell for each of the four regulation configurations.

[0187] FIG. 11 shows the trend of the cell temperature during runaway for each of the four regulation configurations.

[0188] As shown by the curves in Figures 10 and 11, flow regulation causes a significant reduction in temperature in both the runaway cell and the adjacent cells. In particular, the maximum temperatures of the runaway cell and the adjacent cell change correspondingly from 752°C and 68.3°C in the reference case to 489°C and 58.2°C when the entire coolant flow is diverted to the runaway module.

[0189] Furthermore, the cooling dynamics are significantly improved by flow rate regulation: in the two most favorable cases, i.e., when coolant is essentially diverted to the runaway module, the adjacent cells return to their pre-runaway temperatures in less than 10 s.

[0190] Without adjustment, the cooling time is multiplied by 3.5 (Figure 10).

[0191] Therefore, adjusting the flow rate in favor of the runaway module(s) significantly limits the temperature rise of the runaway cell and adjacent cells, thereby reducing the risk of runaway propagation. Such a result is therefore a major advance from a safety perspective.

[0192] Flow regulation also has a positive effect on the life of cells that do not directly experience runaway, by reducing the thermal stress experienced (a combination of factors such as maximum temperature reached, duration of runaway, and temperature uniformity within the cell).

Claims

1. 1. A method for thermal and safety management of a battery in an apparatus comprising a battery including a plurality of modules each including a plurality of cells, and a cooling circuit comprising a circulation loop for a coolant and an adjusting valve for adjusting the flow rate of the coolant upstream of each of the modules, comprising: a) detecting a failure of at least one cell of a module; b) if a fault is detected, a flow redirection step including increasing the coolant flow rate through the module(s) containing at least one faulty cell.

2. 2. The method of claim 1, wherein at least 50% of the flow rate of the coolant is diverted to the one or more modules containing at least one faulty cell, preferably at least 70% of the flow rate, other preferably at least 90% of the flow rate or 100% of the flow rate of the coolant is directed to the one or more modules containing at least one faulty cell.

3. 3. The method according to claim 1 or 2, wherein step a) comprises: a1) setting a threshold value for at least one parameter selected from temperature, voltage, and current; a2) measuring at least one parameter selected from temperature, voltage and current during battery operation; a3) detecting a fault if the measured parameter is higher or lower than the threshold set during step a1.

4. 4. The method of claim 3, wherein the parameter is the temperature of the coolant, the method comprising: a1) setting a temperature threshold that should not be exceeded; a2) measuring the coolant temperature at the outlet of each of the modules or at the outlet of each of the cells; a3) detecting a failure of at least one given module or cell when the temperature measured at the outlet of said module or cell exceeds said temperature threshold; b) diverting at least a portion of the flow rate of the coolant toward the failed module or the module containing the failed cell.

5. 4. The method of claim 3, wherein the parameter is the temperature of each of the modules or each of the cells, the method comprising: a1) setting a temperature threshold for each of said modules or each of said cells that should not be exceeded; a2) measuring the temperature of each of the modules of each of the cells; a3) detecting a failure of at least one given module or at least one given cell when the measured temperature of the module or cell exceeds the temperature threshold; b) diverting at least a portion of the flow rate of the coolant toward the failed module or the module containing the failed cell.

6. 3. The method according to claim 1 or 2, wherein step a) comprises: a1) selecting a threshold for changing at least one parameter selected from temperature, voltage and current during a given time; a2) measuring said parameters during battery operation; a3) detecting a failure of at least one given module or at least one given cell when said threshold is exceeded.

7. 7. The method of claim 1, wherein step b) further comprises reducing the flow rate of the coolant in one or more of the modules that do not have a failed cell.

8. 8. The method of claim 1, wherein the adjusting step b) is performed until one or more of the faulty cells return to rated operation.

9. Apparatus for carrying out the method of any one of claims 1 to 8, comprising: a battery comprising a plurality of modules each comprising a plurality of electrochemical cells; - a cooling system, - a circulation loop for the coolant; at least one valve upstream of each of said modules for controlling the flow rate of said coolant; and a cooling system including:

10. 10. The apparatus of claim 9, wherein the at least one valve is a shut-off valve that acts to stop the circulation of the fluid in the module that does not contain any failed cell(s).

11. 11. The apparatus according to claim 9 or 10, further comprising a control unit for detecting at least one faulty cell.

12. 12. The device according to any one of claims 9 to 11, further comprising at least one sensor at the outlet of each of the modules or each of the cells, which allows measurement of at least one parameter selected from the temperature and the current of the coolant.

13. 13. The apparatus according to any one of claims 9 to 12, further comprising an air conditioning circuit through which a refrigerant fluid flows.

14. 14. Device according to claim 13, wherein the cooling circuit further comprises at least one heat exchanger intended to exchange heat with air or with a refrigerant fluid of the air conditioning circuit.

15. 13. Apparatus according to any one of claims 9 to 12, wherein the cooling circuit further comprises at least one heat exchanger intended to exchange heat with the air.

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