Automotive battery module

Abstract

The present invention relates to a battery (3) module (7) including a case (8) for housing a power storage cell (9) and a monitoring device (19) for diagnosing degradation of at least one of the power storage cells (9) housed in the case (8) of the module (7), the monitoring device (19) monitoring characteristics other than the temperature of a fluid housed in the case (8) of the module (7).

Description

Technical Field

[0001] The present invention relates to batteries, and more precisely to the field of automotive battery modules.

Background Art

[0002] Regarding the power storage capacity of automobiles, especially as countries impose pollution control standards based on laws, further improvement is required. Certainly, when using batteries, it is possible to avoid pollution caused by combustion by replacing all or part of the heat engine with an electric motor, but it is not always possible to replace it under the same usage conditions.

[0003] The main disadvantage lies, especially, in the risk of thermal runaway of the power storage cells in lithium-ion type batteries. Specifically, when the temperature rises excessively, the electrolyte evaporates due to a chain reaction inside the power storage cell, which causes an overpressure state inside the power storage cell. In the worst case, some or even all of the power storage cells may fall into thermal runaway, which may cause a fire in the battery, and incidentally, a fire in all or part of the members around the battery, that is, especially in all or part of the automobile to which the battery is attached.

[0004] These disadvantages have already been addressed in each of the documents of International Publication No. 2021 / 001108, European Patent Application Publication No. 3910349, German Patent Application Publication No. 102020109269, French Patent Application Publication No. 3112028, US Patent Application Publication No. 2012 / 003515, European Patent Application Publication No. 3166175 and the paper "A survey of methods for monitoring and detecting thermal runaway of lithium-ion batteries", Journal of Power Sources, published by Elsevier, No. 436, July 20, 2019, ISSN: 0378-7753.

[0005] Furthermore, as a more serious problem, as the consumption current of the battery increases, the discharge power of the battery increases (Joule effect that increases according to the square of the discharge current), the usage frequency of the user's rapid charging stand increases (Joule effect that increases according to the square of the charging current), and thereby the risk of thermal runaway further increases.

[0006] Thus, for automobiles that are obliged to comply with pollution control standards that are becoming increasingly strict, the temperature control of the battery has become a major issue.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Non-Patent Documents

[0008]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0009] The present invention aims to provide a battery module capable of quickly detecting the risk of thermal runaway of a power storage cell housed in the battery module, among other things.

Means for Solving the Problems

[0010] For this purpose, the present invention is an automotive battery module including a case for housing a power storage cell, wherein the battery module includes a monitoring device for monitoring the characteristics of a fluid housed in the module case in order to diagnose the deterioration of at least one of the power storage cells housed in the module case, the monitoring device includes at least one detection element attached to the module case for identifying the presence of a contaminated fluid leaked from at least one of the power storage cells different from the fluid housed in the module case, and the detection element includes a conductivity sensor for measuring a change in conductivity in the fluid housed in the module case caused by the contaminated fluid leaked from at least one of the power storage cells.

[0011] According to the present invention, it is assumed that the battery is formed by a plurality of modules electrically connected in parallel or in series, which has several advantages. First, it is easier to adjust the temperature of a plurality of battery modules than that of an integrated type including the same number of power storage cells. Also, it is easier to mount a plurality of battery modules on an automobile than an integrated type including the same number of power storage cells. Further, when there is a problem in only a part of the power storage cells, it is easier to replace the module including the defective power storage cell than to replace the entire battery. Thus, it is understood that the defective power storage cell can be quickly identified because the battery module to be checked is already known by the diagnosis of the monitoring device.

[0012] Furthermore, advantageously, according to the present invention, each module is capable of detecting the degradation of at least one of its storage cells in order to quickly stop the thermal runaway of the battery. An obvious solution to solve the problem of thermal runaway would be to monitor the temperature of the storage cells. However, in reality, since the temperature rise occurs just before ignition, this is not the solution pursued by the present invention.

[0013] For example, in order to avoid deformation of each storage cell, i.e., degradation of the members around the storage cell, when the predetermined internal pressure is exceeded, an exhaust valve is usually provided, which is often formed by a breakable part that breaks to release excessive pressure outside the storage cell. When the exhaust valve opens in this way, the storage cell ceases to function.

[0014] Therefore, based on such recognition, the present invention monitors at least one characteristic other than temperature, such as the conductivity of the fluid in the battery module, and possibly further its components, pressure or transparency, instead of tracking the temperature of each storage cell, to identify whether a contaminated fluid such as gas is leaking from at least one of the storage cells of the module, and quickly diagnose the possibility of thermal runaway.

[0015] In fact, attaching a temperature sensor to each storage cell is costly and complex, and even measuring a single temperature within the case cannot reliably and sufficiently early detect the thermal runaway of any one storage cell. According to the present invention, in a different way, an abnormality is detected after the destruction of at least one of the storage cells. Thus, the location where thermal runaway occurs in the battery module is immediately identified at a stage sufficiently before the thermal runaway spreads to other storage cells of the battery module and / or other battery modules (especially earlier than in the case of temperature monitoring). Furthermore, according to the present invention, advantageously, the monitoring device is compatible with various types of temperature control systems.

[0016] According to the present invention, advantageously, the detection element can be attached both inside and outside the case of each module, depending on the mounting method or type of the battery. Of course, for improving the diagnostic ability, a plurality of the same detection elements (detecting the same kind of characteristics of the fluid in the battery module) and / or different detection elements (detecting a plurality of different characteristics of the fluid in the battery module) may exist on the same module.

[0017] A conductivity sensor is preferred because it has high reliability for detecting characteristics in the fluid compared to other characteristics. For example, the conductivity sensor is less affected by other characteristics of the fluid (such as color, transparency, etc.) that may interfere with / change the measured value of the characteristic. In other words, the conductivity sensor has fewer measurement errors than other types of sensors in the context of the present invention.

[0018] According to the present invention, advantageously, when the change in the conductivity (or conversely, resistivity) of the fluid in the module deviates from a predetermined threshold value (such as the average conductivity of other battery modules, the deviation from the normal conductivity at a specific temperature, or the deviation from a predetermined conductivity), the monitoring device can immediately diagnose that there is a possibility of thermal runaway.

[0019] According to the present invention, advantageously, in the case of a special case where the fluid is air, the conductivity sensor can usually also detect an increase in humidity in the air that causes a short circuit (dielectric breakdown of air) that occurs before thermal runaway. In other words, the conductivity sensor can not only diagnose thermal runaway but also avoid it. Other types of sensors such as temperature sensors and pressure sensors cannot avoid this.

[0020] The present invention can also include one or more of the following optional features alone or in combination.

[0021] The detection element can further include a concentration sensor for measuring the concentration of the contaminated fluid leaked into the fluid accommodated in the module case from at least one of the power storage cells. That is, it is understood that if a very small part of the contaminated fluid exists, the monitoring device can immediately diagnose that there is a possibility of thermal runaway.

[0022] The detection element can further include a pressure sensor for measuring a change in pressure within the fluid contained in the case of each module, which is caused by a contaminated fluid leaking from at least one of the power storage cells. According to the present invention, advantageously, when the change in the pressure of the fluid within the module exceeds a predetermined threshold (such as the average pressure of other battery modules, the deviation from the normal pressure at a specific temperature, or the deviation from a predetermined pressure), the monitoring device can immediately diagnose that there is a possibility of thermal runaway.

[0023] The detection element can further include an optical sensor for measuring a change in light transmission within the fluid contained in the case of each module, which is caused by a contaminated fluid leaking from at least one of the power storage cells. According to the present invention, advantageously, when the change in the light intensity of the fluid within the module deviates from a predetermined threshold (such as the average light intensity of other battery modules or the deviation from a predetermined light intensity), the monitoring device can immediately diagnose that there is a possibility of thermal runaway. It is noted that this last type of sensor can also enable other additional detections. For example, immediately after ignition within the module, the monitoring device can detect smoke due to a decrease in light intensity or, conversely, a flame due to an increase in light intensity. Further, when the fluid within the module is a liquid, the monitoring device can detect gas bubbles leaking from the power storage cell based on the change in light intensity.

[0024] The monitoring device can include at least one guiding element attached to the case of the module for redirecting the contaminated fluid leaking from at least one of the power storage cells towards the detection element, for the purpose of improving the reliability of detection and suppressing the number of detection elements. It is understood that this guiding element can form a part of the upper cover of the case of each module in order to allow the contaminated fluid to pass in front of each detection element. In this way, the guiding element can form a collector that forces all the contaminated fluid to pass in front of each detection element.

[0025] The fluid contained in the module case can be a gaseous air or a liquid-phase dielectric heat transfer fluid that thermally regulates at least a part of the power storage cells included in the battery module.

[0026] The present invention is a temperature control system for an automotive battery module as introduced above, characterized in that the temperature control system includes a control unit electrically connected to a monitoring device for a fluid contained in the module case in order to selectively control the function of the temperature control system in response to a diagnosed deterioration of at least one of the power storage cells housed in the module case.

[0027] Furthermore, the present invention is directed to an automobile characterized by including the temperature control system as introduced above.

[0028] Other features and advantages of the present invention will become apparent from the following description, which is presented as a non-limiting guideline only with reference to the accompanying drawings.

Brief Description of the Drawings

[0029]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0030] Hereinafter, the directions are those of the respective drawings. Specifically, the terms "up", "down", "left", "right", "above", "below", "forward", and "backward" are generally understood with respect to the directions shown in the respective drawings.

[0031] The present invention is applicable to all types of battery 3 temperature control systems 1, such as systems equipped on work vehicles selected from among vehicles 4 of the passenger car type, SUVs ("Sport Utility Vehicles"), motorcycles (especially bikes), airplanes, and small trucks, "large transport vehicles" (i.e., off-road vehicles such as subways, buses, long-distance transport vehicles [trucks, tractors, trailers], agricultural or construction machinery), or other transport vehicles or cargo handling machines.

[0032] The vehicle 4 can be of the electric type, i.e., having at least one electric motor powered by at least one battery, the hybrid type, i.e., having at least one internal combustion engine supplied with at least one fuel (such as gasoline, liquefied petroleum gas, diesel oil, natural gas for vehicles, biofuels such as ethanol obtained mainly from plant materials, etc.) and assisted by at least one electric motor powered by at least one battery and / or the in-vehicle electrical network of the vehicle 4, the fuel cell type, i.e., having at least one electric motor powered by at least one battery and / or a fuel cell using hydrogen and oxygen (supplied, for example, from a pressure tank and ambient air, respectively) as fuel, or the plug-in hybrid type, i.e., having at least one internal combustion engine supplied with at least one fuel (such as gasoline, liquefied petroleum gas, diesel oil, natural gas for vehicles, biofuels such as ethanol obtained mainly from plant materials, etc.) and at least one electric motor powered by at least one rechargeable battery connected to the in-vehicle electrical network of the vehicle 4 and / or an external electrical network of the vehicle 4. Of course, the present invention is not limited to the above examples of each vehicle 4, and is applicable to all types of vehicles 4 including at least one battery without departing from the framework of the present invention.

[0033] The "temperature control system 1" refers to any type of system 1 capable of managing the flow, temperature, and pressure of a heat-conducting fluid that performs heat exchange (exchange by immersion in a dielectric heat-conducting fluid, exchange by blowing air, exchange by an air-exchanger) with all or part of the electricity storage cells 9 by moving the heat-conducting fluid surrounding a part of the electricity storage cells 9 in the battery 3 in order to control the temperature of the electricity storage cells, that is, to typically heat and / or cool all or part of the electricity storage cells 9 in at least one battery 3 module 7 according to a predetermined control.

[0034] The "heat-conducting fluid" refers to the fluid of the temperature control system 1 capable of exchanging cold and / or warm heat of at least part of the electricity storage cells 9 in the battery 3 by contact. Typically, the heat-conducting fluid can circulate around all or part of the electricity storage cells 9 by filling at least part of the battery 3 module 7.

[0035] The "dielectric heat-conducting fluid" refers to the fluid that remains liquid in the battery 3 module 7 of the temperature control system 1 in order to exchange cold and / or warm heat of at least part of the electricity storage cells 9 in the battery 3 by contact. Typically, the dielectric heat-conducting fluid is single-phase, that is, it does not undergo a phase change (remains liquid) in the temperature range during normal operation, for example, between -40°C and 60°C. According to the present invention, the heat-conducting fluid is dielectric, and preferably has an electrical resistivity ρ of 1·10 9 ohm-meter (1 GΩ·m) or more at a temperature of 300 Kelvin (300K), or conversely, a conductivity σ of 1·10 -9 Siemens per meter (1 nS·m -1)The following is shown. This type of dielectric heat transfer fluid can be a fluid similar to those used in transformers. That is, since it is known per se, no further explanation will be given in this specification. By way of non-limiting example only, the dielectric heat transfer fluid can be, for example, the Novec® 7500 type sold by 3M, the F18 or F20 type sold by Total®, or the DF7 or DFK type products sold by MiVolt®.

[0036] "Characteristics of the fluid" refers to the physicochemical characteristics of the fluid, not the mass or volume of the fluid.

[0037] "Energy storage cell 9" refers to any type of electrochemical energy storage battery that can store electrical energy and, reversibly, release the stored electrical energy.

[0038] "Battery 3 module 7" refers to a case 8 that groups together at least two of the energy storage cells 9 that are electrically connected in series or in parallel. In the framework of the present invention, in order to thermally regulate at least a part of the energy storage cells 9 housed in the battery 3 module 7, the circulation of the heat transfer fluid in at least one battery 3 module 7 is envisaged.

[0039] "Battery 3" refers to a module 7 assembly that is electrically connected in series or in parallel, and, incidentally, an energy storage cell 9 assembly included in the module 7.

[0040] "Power train 2" refers to an assembly that includes one (or more) engines that directly or indirectly drive the wheels of the motor vehicle 4, and accessories of each engine, such as, for example, an alternator, a cooling system, a gearbox or a lubrication system.

[0041] In the example described in FIG. 1, the temperature control system 1 of the battery 3 is attached to the automobile 4. In this example, an electrical connection element 5 for charging the battery 3 is provided on the vehicle body of the automobile 4. As described above, the temperature control system 1 and / or the battery 3 can be fluidly and / or electrically connected to the powertrain 2. According to the present invention, advantageously, due to all the features and technical effects of the temperature control system 1, the exchange of electrical energy between the battery 3 and each component of the automobile 4 is optimally performed, for example, while the automobile is running or during charging when parked.

[0042] According to the present invention, the temperature control system 1 can advantageously be of a plurality of types. The heat-conducting fluid housed in the case 8 of the module 7 can be a gaseous air or a liquid-phase dielectric heat-conducting fluid that temperature-controls at least a part of the power storage cells 9 contained within the battery 3 module 7. The battery 3 module 7 also enables the power storage cells 9 to be electrically connected to this part for supplying electrical energy to other parts of the automobile 4. These electrical connections are established by waterproof connectors. Each battery 3 module 7 includes a case 8 consisting of a hollow lower base 8b (for receiving the power storage cells 9) sealed by an upper lid 8a to protect the power storage cells 9 from physical incidents (such as collisions and physical impacts), and also for protection during ignition (to suppress the spread of external flames to each battery 3 module 7 and prevent the flames from reaching the power storage cells 9).

[0043] According to the present invention, the temperature control system 1 includes a control unit 11 that is electrically connected to a monitoring device 19 for the fluid housed in the case 8 of the battery 3 module 7 to selectively control the function of the temperature control system 1 in response to the diagnosed deterioration of at least one of the power storage cells 9 housed in the case 8.

[0044] In the example described in FIG. 2 showing the first embodiment according to the present invention, the temperature control system 1 can include an immersion type of the power storage cell 9, that is, a case 8 in which each battery 3 module 7 houses the power storage cell 9 in a dielectric heat transfer fluid. Preferably, the power storage cell 9 of each battery 3 module 7 is completely immersed in the dielectric heat transfer fluid forming a part of the fluid network 6. Preferably, the plurality of battery 3 modules 7 are fluidly connected to other parts of the fluid network 6 by fluid connections to the common inflow path 10 and the common outflow path 12. In the example described in FIG. 2, three battery 3 modules 7 are arranged in parallel in the fluid network 6 so that each power storage cell 9 can be uniformly temperature-controlled by supplying the dielectric heat transfer fluid to each battery 3 module 7 fairly and uniformly. Such a parallel arrangement can also reduce the pressure loss in the fluid network 6. To equalize the pressure loss at each connection of the battery 3 modules 7 (i.e., to make the flow rate in each module equal), the fluid connection cross-section between the common inflow path 10 and the corresponding battery 3 module 7 varies in size according to the distance from the connection to the fluid network 6 so that the flow rate of the dielectric heat transfer fluid between each battery 3 module 7 is equal.

[0045] In the example described in FIG. 3 showing the second embodiment according to the present invention, the temperature control system 1 can be of a heat exchanger 18 type containing a heat transfer fluid around the storage battery cell 9, that is, a type in which each battery 3 module 7 includes a case 8 that houses the storage battery cell 9 and the heat exchanger 18. Preferably, the storage battery cells 9 of each battery 3 module 7 are heated or cooled by a heat exchanger 18 that forms part of the fluid network 6 of the temperature control system 1 via the heat transfer fluid within the case 8. Preferably, the plurality of battery 3 modules 7 are fluid-connected to other parts of the fluid network 6 by hydraulic connection to the common inflow passage 10 and the common outflow passage 12. In the example described in FIG. 3, the battery 3 modules 7 (only one point in FIG. 3) are arranged in parallel within the fluid network 6 so that each storage battery cell 9 can be uniformly temperature-controlled by supplying the heat transfer fluid to each heat exchanger 18 of each battery 3 module 7 fairly and uniformly. Such a parallel arrangement can also reduce the pressure loss between the inlet 10' and the outlet 12' of the heat exchanger 18 within the case 8 in the fluid network 6.

[0046] Therefore, it is understood that the temperature control system 1 according to the present invention can optimally maintain the temperature of the storage battery cell 9 in order to ensure the optimal operation (maintaining the best energy efficiency) and high durability (extending the service life by optimal charging and discharging) of the battery 3 regardless of the external conditions under which the vehicle 4 travels, such as extremely cold or hot weather.

[0047] In a simpler solution, it is also conceivable not to use the heat exchanger 18 at all and to have a heat transfer fluid such as atmospheric air sucked into the case 8 by a ventilation device and sent out from the case 8 (third embodiment, not shown). In the case of this third embodiment, it is understood that the heating and cooling capabilities of the temperature control system 1 are significantly more limited than in the previous two embodiments.

[0048] Typically, the immersion example of the first embodiment can perform heat exchange most efficiently. This is because the exchange specific surface area is larger, and the dielectric heat transfer fluid circulates and is quickly discharged outside each battery 3 module 7. As a result, high efficiency and adjustment power are obtained, enabling charging and discharging of the large power of the battery (charging in a rapid charging stand) and power consumption of the automobile 4 at high load. Furthermore, since the heat exchange is directly performed by the convection of the heat transfer fluid on the casing of each power storage cell 9, it is extremely effective. Incidentally, the adjustment by immersion more reliably prevents the spread of fire even when the battery 3 of the automobile 4 catches fire.

[0049] According to the present invention, advantageously, each battery 3 module 7 includes a monitoring device 19 for monitoring characteristics other than the temperature of the fluid accommodated in the case 8 of the module 7 in order to diagnose the deterioration of at least one of the power storage cells 9 accommodated in the case 8.

[0050] According to the present invention, it is assumed that the battery 3 is formed by a plurality of modules 7 that are electrically connected in parallel or in series, which has several advantages. First, it is easier to adjust the temperature of a plurality of battery 3 modules 7 than an integrated type having the same number of power storage cells 9. Also, it is easier to mount a plurality of battery 3 modules 7 on the automobile 4 than an integrated type including the same number of power storage cells 9. Furthermore, when there is a defect in only a part of the power storage cells 9, it is easier to replace the battery 3 module 7 including the defective power storage cell 9 than to replace the entire battery 3. Thus, it is understood that the defective power storage cell 9 can be quickly identified because the battery 3 module 7 to be confirmed is already known by the diagnosis of the monitoring device 19.

[0051] Furthermore, advantageously, according to the present invention, each battery 3 module 7 is capable of detecting the deterioration of at least one of its power storage cells 9 in order to quickly stop the thermal runaway of the battery 3. An obvious solution to solve the problem of thermal runaway would be to monitor the temperature of the power storage cell 9. However, this is not the solution pursued by the present invention.

[0052] For example, in order to avoid deformation of each power storage cell 9, that is, deterioration of members around each power storage cell 9, it has been confirmed that an exhaust valve 21 is usually provided which breaks to release excessive pressure outside the power storage cell 9 when a predetermined internal pressure is exceeded. When the exhaust valve 21 opens in this way, the power storage cell 9 ceases to function.

[0053] Therefore, based on such recognition, the present invention monitors at least one characteristic other than temperature, such as the conductivity of the fluid in the battery 3 module 7, and possibly further its components, pressure or transparency, instead of tracking the temperature of each power storage cell 9, to identify whether fluid such as gas is leaking from at least one of the power storage cells 9 in the battery 3 module 7, and diagnose the possibility of thermal runaway at an early stage. In fact, attaching a temperature sensor to each power storage cell 9 is costly and complicated, and even measuring a single temperature in the case 8 cannot reliably and sufficiently early detect thermal runaway of any one of the power storage cells 9. According to the present invention, in a different way, an abnormality is detected after at least one of the power storage cells 9 is destroyed. Thus, the location where thermal runaway occurs in the battery 3 module 7 is immediately identified at a stage sufficiently prior to the thermal runaway spreading to other power storage cells 9 and / or other battery 3 modules 7 in the battery 3 module 7. Further, according to the present invention, advantageously, the monitoring device 19 has compatibility with various types of temperature control systems 1 as described above.

[0054] The monitoring device 19 includes at least one detection element 13 mounted on the case 8 of the module 7 for identifying the presence of a contaminated fluid leaked from at least one of the power storage cells 9, which is different from the fluid housed in the case 8 of the battery module 7. According to the present invention, advantageously, the detection element 13 can be mounted either inside or outside the case 8 depending on the mounting method or type of the battery 3. Of course, for improving the diagnostic ability of the control unit 11, the same detection element 13 (detecting the same kind of characteristics of the fluid in the battery 3 module 7) and / or different detection elements (detecting a plurality of different characteristics of the fluid in the battery 3 module 7) may be present in plurality on the same module 7.

[0055] According to the present invention, the detection element 13 includes at least one conductivity sensor for measuring a change in the conductivity of the fluid housed in the case 8 caused by a contaminated fluid leaked from at least one of the power storage cells 9. According to the present invention, advantageously, when the change in the conductivity (or conversely, resistivity) of the fluid in the battery 3 module 7 deviates from a predetermined threshold value (such as the average conductivity of other battery 3 modules 7, the deviation from the normal conductivity at a specific temperature, or the deviation from a predetermined conductivity), the monitoring device 19 can immediately diagnose that there is a possibility of thermal runaway. By way of a non-limiting example only, the conductivity sensor can be an electrode sensor.

[0056] The conductivity sensor is preferred because it has high reliability for detecting the characteristics in the fluid as compared with other characteristics. For example, the conductivity sensor is less affected by other characteristics of the fluid (such as color, transparency, etc.) that may interfere with / change the measured value of the characteristics. In other words, the conductivity sensor has fewer measurement errors than other types of sensors in the context of the present invention.

[0057] Also, in the special case where the fluid is air, the conductivity sensor can usually also detect an increase in the humidity in the air that causes a short circuit (dielectric breakdown of air) occurring before thermal runaway. In other words, the conductivity sensor can not only diagnose thermal runaway but also avoid it. None of the other types of sensors such as temperature sensors and pressure sensors can avoid this.

[0058] According to the first modified embodiment, the detection element 13 can further include a concentration sensor for measuring the concentration of the contaminated fluid leaked into the fluid contained in the case 8 from at least one of the power storage cells 9. That is, it is understood that if a very small part of the contaminated fluid is present, the monitoring device 19 can immediately diagnose the possibility of thermal runaway.

[0059] According to the second modified embodiment, the detection element 13 can further include a pressure sensor for measuring a change in the pressure in the fluid contained in the case 8 caused by the contaminated fluid leaked from at least one of the power storage cells 9. According to the present invention, advantageously, if the change in the pressure of the fluid in the battery 3 module 7 exceeds a predetermined threshold value (such as the average pressure of other battery 3 modules 7, the deviation from the normal pressure at a specific temperature, or the deviation from a predetermined pressure such as the atmospheric pressure outside the case 8), the monitoring device 19 can immediately diagnose the possibility of thermal runaway.

[0060] According to the third modified embodiment, the detection element 13 can further include an optical sensor for measuring a change in light transmission in the fluid contained in the case 8 caused by the contaminated fluid leaked from at least one of the power storage cells 9. According to the present invention, advantageously, if the change in the light intensity of the fluid in the battery 3 module 7 deviates from a predetermined threshold value (such as the average light intensity of other battery 3 modules 7 or the deviation from a predetermined light intensity), the monitoring device 19 can immediately diagnose the possibility of thermal runaway. It is noted that this last type of sensor can also perform other additional detections. For example, immediately after ignition in the battery module 7, the monitoring device 19 can detect smoke due to a decrease in light intensity or, conversely, detect a flame due to an increase in light intensity. Further, when the dielectric heat-conducting fluid in the battery 3 module 7 is in the liquid phase, the monitoring device 19 can detect gas bubbles leaked from the power storage cell 9 due to a change in light intensity.

[0061] According to the present invention, advantageously, the monitoring device 19 can include at least one guiding element 17 attached to the case 8 for diverting the contaminated fluid leaked from at least one of the power storage cells 9 towards the detection element 13, for the purpose of improving the reliability of detection and suppressing the number of detection elements 13. It is understood that this guiding element 17 can form part of the upper lid 8a of the case 8 in order to allow the contaminated fluid to pass in front of each detection element 13. In this way, the guiding element 17 can form a collector that forces all the contaminated fluid to pass in front of each detection element 13.

[0062] As can be seen in the example shown in FIG. 3, the guiding element 17 can include, for example, a deflector 16 above a part of the power storage cell 9 in order to force all the contaminated fluid generated from any of the power storage cells 9 to be compulsorily sent to the detection zone 14 of the detection element 13 before being discharged in the direction of the outlet 15.

[0063] Of course, the guiding element 17 can also simply force all the contaminated fluid generated from any of the power storage cells 9 to pass through the detection zone 14 of the detection element 13 located outside the case 8 of the module 7, preferably near the outlet 15, and be discharged in the direction of the outlet 15.

[0064] The present invention is not limited to the introduced embodiments and modified embodiments, and other embodiments and modified embodiments will also be self-evidently derived for those skilled in the art. Therefore, the embodiments and modified embodiments can be combined with each other without departing from the framework of the present invention. Without being limited to this, it is also possible to use other types of detection elements 13 that can detect the contaminated fluid from any of the power storage cells 9 without departing from the framework of the present invention. In addition, a temperature detection element T02 can be used to thermally weight sensors such as, for example, pressure sensors and / or conductivity sensors.

Explanation of Reference Numerals

[0065] 1 Temperature control system 2 Power train 3 Battery 4 Automobile 5 Electrical connection element 6 Fluid network 7 Battery module 8 Case of the battery module 8a Upper cover of the case 8b Hollow lower base of the case 9 Energy storage cell 10 Common inflow path 10’ Inlet 11 Control unit 12 Common outflow path 12’ Outlet 13 Detection element 14 Detection zone 15 Contaminated fluid outlet 16 Deflector 17 Guide element 18 Heat exchanger 19 Monitoring device 21 Exhaust valve T02 Temperature detection element of the module

Claims

1. A battery (3) module (7) for a motor vehicle (4) including a case (8) for housing a storage battery cell (9), wherein in order to diagnose degradation of at least one of the storage battery cells (9) housed in the case (8) of the module (7), it includes a monitoring device (19) for monitoring characteristics of a fluid housed in the case (8) of the module (7), the monitoring device (19) includes at least one detection element (13) attached to the case (8) of the module (7) for identifying the presence of a contaminated fluid leaked from at least one of the storage battery cells (9) different from the fluid housed in the case (8) of the module (7), and the detection element (13) includes a conductivity sensor for measuring a change in conductivity in the fluid housed in the case (8) of the module (7) caused by the contaminated fluid leaked from at least one of the storage battery cells (9). The battery (3) module (7) is characterized by this.

2. The battery (3) module (7) according to claim 1, wherein the detection element (13) further includes a concentration sensor for measuring the concentration of the contaminated fluid leaked from at least one of the storage battery cells (9) into the fluid housed in the case (8) of the module (7).

3. The battery (3) module (7) according to claim 1 or 2, wherein the detection element (13) further includes a pressure sensor for measuring a change in pressure in the fluid housed in the case (8) of the module (7) caused by the contaminated fluid leaked from at least one of the storage battery cells (9).

4. The battery (3) module (7) according to any one of claims 1 to 3, wherein the detection element (13) further includes an optical sensor for measuring a change in light transmission in the fluid housed in the case (8) of the module (7) caused by the contaminated fluid leaked from at least one of the storage battery cells (9).

5. The battery (3) module (7) according to any one of claims 1 to 4, wherein the monitoring device (19) includes at least one guiding element (17) attached to the case (8) of the module (7) for diverting the contaminated fluid leaked from at least one of the power storage cells (9) toward the detection element (13) for the purpose of improving the reliability of detection and suppressing the number of the detection elements (13).

6. The battery (3) module (7) according to any one of claims 1 to 5, wherein the detection element (13) is attached inside the case (8) of the module (7).

7. The battery (3) module (7) according to any one of claims 1 to 5, wherein the detection element (13) is attached outside the case (8) of the module (7).

8. The battery (3) module (7) according to any one of claims 1 to 7, wherein the fluid accommodated in the case (8) of the module (7) is air.

9. The battery (3) module (7) according to any one of claims 1 to 7, wherein the fluid accommodated in the case (8) of the module (7) is a liquid-phase dielectric heat transfer fluid that temperature-regulates at least a part of the power storage cells (9) included in the battery (3) module (7).

10. A temperature control system (1) for a battery (3) module (7) for an automobile (4) according to any one of claims 1 to 9, the temperature control system (1) including a control unit (11) electrically connected to the monitoring device (19) of the fluid accommodated in the case (8) of the module (7) for selectively controlling the function of the temperature control system (1) according to the diagnosed deterioration of at least one of the power storage cells (9) housed in the case (8) of the module (7).

11. An automobile (4) characterized by including the temperature control system (1) according to claim 10.

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