Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
  • H01M10/4228—Leak testing of cells or batteries
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M3/00—Investigating fluid-tightness of structures
  • G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
  • G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
  • G01M3/32—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for containers, e.g. radiators
  • G01M3/3209—Details, e.g. container closure devices
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M3/00—Investigating fluid-tightness of structures
  • G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
  • G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
  • G01M3/32—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for containers, e.g. radiators
  • G01M3/3236—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for containers, e.g. radiators by monitoring the interior space of the containers
  • G01M3/3272—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for containers, e.g. radiators by monitoring the interior space of the containers for verifying the internal pressure of closed containers
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M3/00—Investigating fluid-tightness of structures
  • G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
  • G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
  • G01M3/32—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for containers, e.g. radiators
  • G01M3/34—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for containers, e.g. radiators by testing the possibility of maintaining the vacuum in containers, e.g. in can-testing machines
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
  • G01R31/52—Testing for short-circuits, leakage current or ground faults
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
  • H01M10/4285—Testing apparatus
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
  • H01M10/48—Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/50—Current conducting connections for cells or batteries
  • H01M50/569—Constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M2200/00—Safety devices for primary or secondary batteries
  • H01M2200/20—Pressure-sensitive devices
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M2220/00—Batteries for particular applications
  • H01M2220/20—Batteries in motive systems, e.g. vehicle, ship, plane
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
  • H01M50/249—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders specially adapted for aircraft or vehicles, e.g. cars or trains

Definitions

• the present invention relates to the field of leak detection (or sealing measurement) devices for motor vehicle battery packs.
• battery pack means traction and/or function batteries, generally accompanied by a thermal management system for said battery, which are intended to be embedded in electric and hybrid vehicles.
• the thermal management system is, for example, a network of fluid ducts making it possible to cool or heat the battery as needed.
• These batteries generally of the Lithium-Ion type, are arranged in specific casings (such as a rigid envelope), these casings generally integrating the thermal management system, the assembly thus forming a battery pack for a motor vehicle.
• the invention is thus a leak detection device for a motor vehicle battery pack, said device comprising:
• a pneumatic circuit comprising a plurality of valves and a pressure sensor
• At least one connector for connecting said pneumatic circuit to at least one element of the battery pack; said device being configured to operate at least one leak detection procedure on at least one element of the battery pack via the pneumatic circuit and the connector.
• the invention is thus a leak detection device for a motor vehicle battery pack, said device comprising:
• a pneumatic circuit comprising a plurality of valves, a pressure sensor and a pump;
• At least one connector for connecting said circuit to at least one element of the battery pack; said device being configured to operate at least one leak detection procedure on at least one element of the battery pack via the pneumatic circuit and the connector.
• the device according to the invention can thus test the presence of leaks on one or more elements of a battery pack, more particularly the tightness of the housing of the battery and/or of the thermal management system of the battery.
• the pneumatic circuit comprises a pump (or a compressor), said pneumatic circuit being configured to operate pressure and/or vacuum leak detection procedures.
• said pneumatic circuit is configured to operate pressure and/or vacuum leak detection procedures.
• Said device according to the invention is thus configured to carry out tests under pressure or under vacuum, that is to say by varying positively or negatively the pressure in the volume whose tightness is to be tested.
• said device is configured to generate a relative pressure ranging from ⁇ 1 to 3 bars (in particular thanks to the pump).
• said pump has a flow rate of between 10 to 100 L/min (liters per minute), and preferably between 15 and 30 L/min.
• the device comprises a database relating to procedures for detecting leaks on motor vehicle battery packs.
• the database on board the device allows the operator to select a detection procedure adapted to the element of the battery pack whose tightness is to be tested.
• said database comprises one or more of the following data: vehicle model(s) and/or battery model(s) associated with at least one leak detection procedure.
• the device database advantageously includes a list of motor vehicle models and/or battery pack models to allow the operator to quickly find the most suitable leak detection procedure and to avoid the need to have to configure the various parameters of a leak detection procedure.
• the leak procedures include in particular the leak rate values (generally expressed in cc/min or in pressure variation per unit of time) acceptable for the tested element(s) of the battery pack, these values are generally communicated by the car manufacturer or battery pack manufacturer.
• said at least one leak detection procedure comprises one or more of the following parameters: volume(s) of the battery and/or of the thermal management system, duration of the various stages of the leak test , test pressure, battery filling and/or emptying speed, leakage threshold, flexibility coefficient of a battery pack element.
• One or more of these parameters are preset depending on the model of the vehicle and/or battery, thus avoiding the operator having to make any settings before carrying out a leak detection procedure.
• the device comprises a man-machine interface.
• Said man-machine interface is the set of elements allowing the user to interact with the device, and more particularly to control the device and/or to exchange information with it.
• the human-machine interface includes, for example, one or more of the following elements: button(s), keyboard, screen, touch screen, dial(s), indicator lights, etc.
• said device is configured to present an inclination with respect to the surface (generally the horizontal) on which the device is placed so that the man-machine interface is oriented upwards.
• the inclination of the man-machine interface may be due either to the inclination of the front face of the device incorporating the man-machine interface or the inclination of the case of the device (in particular by means of tabs supports of different lengths).
• the angle of inclination of said device is between 5 and 30 degrees, preferably between 10 and 30 degrees.
• This angle range is advantageous, because it is adapted to the working conditions of the user of said device.
• said device comprises a plurality of magnetic support feet.
• Magnetic support feet make it possible in particular to secure the device according to the invention to a ferromagnetic surface, thus preventing it from moving, for example following a shock or collision.
• said device comprises at least one winding support.
• Said winding support makes it possible in particular to wind a power cable and/or a test conduit (said conduit making it possible to connect the device to the battery pack to be tested).
• said device comprises a gripping handle.
• the handle makes it easy to transport and position the device in the most suitable location for performing leak detection.
• the device comprises a communication module (otherwise called means of communication) with a remote server, said device being configured to download to a remote server one or more of the following data: result of the leak tests , identifier of the operator who carried out the leak test, identifier of said device, identifier of the battery tested, date, measurement signals of the leak tests.
• a communication module otherwise called means of communication
• the device being configured to download to a remote server one or more of the following data: result of the leak tests , identifier of the operator who carried out the leak test, identifier of said device, identifier of the battery tested, date, measurement signals of the leak tests.
• the downloaded data is also used to optimize the detection procedures, for example by means of machine learning, by generating for example sets of modified parameters based on leak detection procedures carried out by devices according to the invention.
• said device is configured to download, for example from a remote server, an update of the sets of parameters of one or more leak detection procedures stored in the database of the device .
• said parameters downloaded by the device are parameters modified following machine learning.
• said device comprises a barcode reader, in particular for reading and storing the identification barcode affixed to a battery pack.
• said device comprises a printer.
• Said printer makes it possible in particular to print a maintenance ticket after using the device on a battery pack.
• the now ticket includes, for example, one or more of the following information: result of the leak tests, identifier of the operator who performed the leak test, identifier of said device, identifier of the battery tested, date and/or measurement signals of the leak tests.
• the device is configured to measure and take into account the value of the back pressure during a leak detection procedure on a battery pack element.
• Back pressure can distort the measurement of pressures and pressure variations, invalidating the measurement of a relevant leak rate.
• the back pressure value is determined, at the start of the test detection procedure for the tested element of the battery pack, by pressure measurements, before and after activation of the pump. of the pneumatic circuit, the difference of these pressure measurements giving the value of the counter-pressure.
• the back-pressure value is determined when the tested element of the battery pack is still empty or being filled.
• the device comprises one or more environment sensors to correct the measurement signals when detecting leaks.
• Said environment sensors are for example one or more temperature, atmospheric pressure, hygrometry, etc. sensors.
• the pressure sensor is an absolute or relative pressure sensor.
• Said sensor is for example a piezoelectric pressure sensor.
• FIG. 3 is a very schematic view of the pneumatic circuit of the device of FIGS. 1 and 2;
• FIG. 4 is a schematic view of the circuit configuration of Figure 3 during a device start-up step
• FIG. 5 is a graph illustrating an example of pressure variation during a leak detection procedure carried out by the device of FIGS. 1 and 2;
• FIG. 6 illustrates the different configurations of the circuit of FIG. 4 during the different stages of leak detection, in pressure, carried out by means of said device of FIGS. 1 and 2;
• FIG. 7 illustrates the different configurations of the circuit of FIG. 4 during the different stages of leak detection, in vacuum, carried out by means of said device of FIGS. 1 and 2;
• FIG. 8 referenced [Fig. 8], is a very schematic representation of a control module of the pneumatic circuit of figure 4.
• FIGs. 1] and [Fig. 2] are very schematic representations in perspective, respectively from the front and from behind, of a leak detection device 1 for a motor vehicle battery pack.
• the leak detection device 1 is a device for testing the tightness of at least one battery pack element by pressure variation. That is to say that the device is configured to carry out a leak detection procedure in which there is a variation of the pressure in the element tested (either by increasing it or by decreasing it) up to a predetermined pressure value, then after a set time there is a pressure measurement. A pressure variation between this predetermined value and the final pressure value then indicates that the element tested has a leak, the device 1 being configured to determine a leak rate as a function of this pressure change over time.
• battery pack means the traction and/or function batteries generally arranged in a casing and accompanied by a thermal management system, this assembly forming a battery pack intended to be embarked in electric vehicles and and hybrids.
• Said thermal management system for its part, comprises for example a network of fluid conduits making it possible to cool or heat the battery.
• detecting leaks on a battery pack is equivalent to testing the tightness (or the level of leaks) of the casing and/or of the thermal management system of the battery.
• the volume of the battery casing generally has a volume of between 50 and 300 liters, while the volume of the thermal management system generally has a volume of between 10 and 50 liters.
• Said device 1 comprises in particular a housing 3 and a man-machine interface 5 (also referred to as the “HMI” below).
• HMI man-machine interface 5
• Said man-machine interface 5 allows, among other things, to start the device 1, and the user to select the operating mode in which the device 1 must be used, for example for a test leaks from the battery case or a battery thermal management system.
• Interface 5 can thus make it possible to select a leak detection procedure (or tightness test procedure) depending on the battery pack to be tested.
• man-machine interface 5 means all the elements allowing the user to interact with the device 1, and more particularly to control the device 1 and to exchange information with that -this.
• the man-machine interface 5 comprises for example one or more of the following elements: button(s), keyboard, screen, touch screen, dial(s), indicator lights, etc.
• the man-machine interface 5 comprises a touch screen 5a, as well as a communication port 5b, for example of the USB type.
• the communication port 5b makes it possible in particular to be able to connect to said device 1 via a third-party device (for example to retrieve data, update the device, etc.).
• Said housing 3, meanwhile, has for example a substantially parallelepipedic shape, as well as a front face 3a, a rear face 3b, a lower face 3c, an upper face 3d and 3rd side faces.
• Said case 3 also comprises support feet 31, at least one winding support 33 and a handle 35 for gripping.
• Each of the support feet 31 comprises magnets (not shown), the latter in particular making it possible to secure the device 1 to a surface (ferromagnetic) during its use and to avoid its inadvertent displacement, for example following a collision or any other external cause.
• Said support feet 31 here each comprise two parts, a tab 31a (for example metal) connected to the housing 3 (at its underside 3c) and a pad 31b disposed on the distal end of said tab 31a.
• Said pads 31b thus comprise one or more magnets, for example overmolded, said pads 31b generally being made of plastic, polymer or a similar material. Said magnetic pads 31b therefore make it possible to secure the device 1 to a metal surface, in particular during a leak detection procedure.
• the support feet 31 are advantageously configured so that the device 1 has an inclination, for example between 10 and 30 degrees with respect to the surface (generally the horizontal) on which the device 1 is placed.
• the front of the device 1 is raised relative to the rear, thus facilitating access for the operator to the man-machine interface 5 and more generally simplifying the use of the device 1.
• only the man-machine interface 5, more particularly the screen 5a has an inclination, for example between 10 and 30 degrees.
• the winding support 33 is configured to allow the winding of a power cable and / or a test duct, such as a flexible air duct.
• Said winding support 33 comprises for example two projections 33a (or tubes, protrusions, etc.) at a distance from each other, preferably arranged on one of the 3rd side faces of said device 1.
• the gripping handle 35 is preferably arranged on the upper face 3d of the housing 3 and in particular facilitates the movement of the device 1 to the place of its use and/or the separation of the support feet 31 from the surface on which the feet 31 are magnetized.
• Said casing 3 may also comprise one or more shockproof protections 37, for example arranged on the corners of casing 3 (in particular at the level of the front 3a and rear 3b faces), to protect the device and/or the operator in the event of of shocks.
• Said protections 37 are for example made of plastic material, rubber, etc., and are in the form of bands surrounding the perimeter (or contour) of the box 3 (covering said corners of the box).
• Said device 1 also comprises a test connector 7 intended to be connected (for example by the test conduit) to the battery pack to be tested.
• Said test connector is for example arranged on the rear face 3b of said device 1.
• the test conduit which makes it possible to connect the device 1 to the battery pack (that is to say to the battery casing and/or thermal management system) includes a suitable connector.
• Said device 1 further comprises a power socket 39 enabling the device 1 to be connected to the electrical network, as well as an On/Off button 41 enabling the device 1 to be switched on or off.
• power supply 39 and button 41 are advantageously arranged on the third rear face of device 1.
• the device 1 also comprises a pneumatic circuit 100, circuit more particularly illustrated in [Fig. 3], said circuit 100 is configured to pressurize or depressurize (or "vacuum") the element of the battery pack whose tightness is to be tested.
• Said pneumatic circuit 100 thus comprises:
• a pump 102 (or a compressor), for example of the volumetric type, configured to pressurize or vacuum the object whose tightness is to be tested (and therefore connected to the pump 102 via the connector 7 and said circuit 100);
• a pressure sensor 104 for example an absolute pressure sensor. Said elements of said circuit being connected to each other via suitable conduits.
• valves Vi and V2, respectively first and second valve are for example 2/2 distributors (or one-way valve), while valve V3, or third valve, is for example a 3/2 distributor (or two-way valve).
• valves V1 and V2 thus have two positions, passing or not passing, that is to say two orifices and the fact of authorizing or not the circulation of fluid between the two orifices of the said valves.
• valve V3 comprises three orifices and two positions, in the present case the first and second orifices are connected to said circuit 100 and the third orifice is to the atmosphere.
• the first or second port is connected to the third, while the remaining port is closed (not through).
• the pump 102 includes a suction inlet or orifice 102a, as well as an outlet or discharge orifice 102b.
• Input 102a of pump 102 is directly connected to valves V 2 and V3, while output 102b is directly connected to valves V 1 and V3.
• the input 102a is connected to a first node Ni which is itself connected to a first orifice of the valve V3 and to a first orifice of the valve V 2 .
• Output 102b is connected to a second node N 2 which is itself connected to a second orifice of valve V3 and to the first orifice of valve V 2 (valve V3 is therefore arranged in parallel with valves V 1 and V 2 ).
• the second orifices of valves V 2 and V3 are for their part connected to a third node N3.
• Node N3 is connected to connector 7 and pressure sensor 104 is placed on the conduit between node N3 and said connector 7.
• Said circuit 100 also comprises at least one control module 106 configured, among other things, to control the elements of the pneumatic circuit 100 (the pump 102, the valves V1-3, etc.).
• Said control module 106 comprises for example one or more electronic cards.
• the device 1 is also configured to carry out a zeroing procedure (or auto-zero) of the pressure prevailing at the level of the pressure sensor 104 during the start-up of said device 1.
• the pump 102 thus draws in air via the valve V3 (therefore generating the creation of a vacuum) and generates an overpressure at the level of the outlet 102b which spreads to the connector 7. This allows to check that the pressure sensor 104 is functional and that the device 1 is not yet connected to an element of a battery pack. This also makes it possible to purge part of the circuit 100, more particularly the part to which said pressure sensor 104 is connected.
• Said device 1 is also configured to include a self-test procedure.
• Said self-test procedure makes it possible to verify the presence of leaks in the device 1, in particular at the level of the circuit 100 and in a test conduit.
• the test output of circuit 100 (with or without a test lead connected to connector 7) is blocked by a plug.
• a leak detection procedure is then initiated, in pressure and/or in vacuum, to check that there are no leaks in the circuit and/or in the test pipe which could falsify the detection of leaks on a part of a battery pack.
• the leak detection device 1 is a device for testing the tightness of at least one battery pack element by pressure variation. That is to say that the device is configured to carry out a leak detection procedure in which there is a variation in the pressure in the element tested (either increasing or decreasing it) up to a predetermined pressure value, then after a set time there is a pressure measurement. A variation in pressure between this predetermined value and the final pressure value then indicates that the element tested has a leak, the device 1 being configured to determine a rate of leaks as a function of this change in pressure over time.
• the [Fig. 5] is a graph illustrating the different steps of a leak detection procedure (in pressure) carried out by the device 1 according to the invention.
• stage I is the filling stage, i.e. the pressure is increased in the tested element of the battery pack, until a determined pressure value is reached.
• Stage II is the stabilization stage, in fact the increase in pressure in the element leads to temperature variations, heat exchanges, etc. which can disturb the measurement, it is therefore necessary to wait a predetermined time t s tab for the transient phenomena which can disturb the measurement to fade.
• Stage III is the measurement stage, the pressure variation measurement during this stage allows the device 1 to calculate a leak rate (for example in cubic centimeters per minute) and to determine whether the element tested has a leak.
• a leak rate for example in cubic centimeters per minute
• Stage IV is the emptying stage, the device 1 is configured so that the pressure of the tested element returns to a pressure value substantially close to atmospheric pressure, this so that the device 1 can be disconnected without risk by the operator.
• the leak detection procedure can also be carried out in vacuum (or under depression), that is to say that instead of increasing the pressure during the first stage, the pressure prevailing in the element to be tested is reduced to a predetermined value. Steps II and III remain unchanged. While the fourth step consists in increasing the pressure prevailing in the tested element up to a pressure value corresponding to the atmospheric pressure. There is therefore an “inversion” of steps I and IV of filling and emptying between the procedures for detecting leaks in pressure and in vacuum.
• the device 1 is configured to perform leak detection procedures according to two different modes, a first mode under pressure (or overpressure) and a second mode under vacuum (or underpressure).
• the [Fig. 6] represents the equivalent configuration of the pneumatic circuit 100 according to the steps of a detection procedure according to the first mode.
• the leak detection procedure comprises the steps described below, with the configurations of the circuit 100 described below.
• valve V3 connects the inlet of the pump 102 to the atmosphere.
• valve V1 connects the output of pump 102 to object PB, via connector 7.
• Device 1 increases the pressure prevailing inside object PB to a predetermined value, the sensor 104 making it possible to measure the value of the pressure and to control the stopping of the pump 102 when the desired pressure value is reached.
• the stabilization and test steps II and III, in which the pump 102 is switched off, while the valves V1 and V2 are closed.
• the stabilization and test steps each respectively have a predetermined duration depending on the element and the battery pack tested, respectively tsta b and .
• the pressure variations measured by the sensor 104 during the test step allow the device 1 to determine a leak rate relating to the object PB tested.
• the leak detection procedure according to a first mode ends with an emptying step IV, step during which the device 1 is configured to bring the pressure prevailing in the object PB down to a pressure value close to atmospheric pressure (or a pressure value compatible with the disconnection, without danger for the operator, of the test conduit to the battery pack).
• Valve V1 is closed and valve V2 connects the tested PB object to the inlet of pump 102. While the outlet of pump 102 is connected to the atmosphere via valve V3. In this configuration, the activation of the pump 102 makes it possible to evacuate the air (generating an overpressure) contained in the object PB tested.
• the [Fig. 7] represents the equivalent configuration of the pneumatic circuit 100 according to the steps of a detection procedure according to the second mode.
• the leak detection procedure comprises the steps described below with the configurations of the circuit 100 described below -After.
• the valve V3 connects the outlet of the pump 102 to the atmosphere.
• valve V 2 connects the outlet of pump 102 to element PB, via connector 7.
• Device 1 decreases the pressure prevailing inside element PB to a predetermined value, the sensor 104 making it possible to measure the value of the pressure and to control the stopping of the pump 102 when the desired pressure value is reached.
• the stabilization and test steps II and III, in which the pump 102 is off, while the valves V 1 and V 2 have closed.
• the stabilization and test steps each respectively have a predetermined duration, respectively tsta b and .
• the pressure variations measured by the sensor 104 during the test step allow the device 1 to determine a leak rate relating to the object PB tested.
• the leak detection procedure according to a second mode ends with a filling step I, step during which the device 1 is configured to increase the pressure prevailing in the object PB up to a pressure value close to atmospheric pressure.
• the device 1 is therefore configured to operate leak detection procedures according to different modes, this is in particular achieved thanks to the control module 106.
• Said control module 106 includes:
• a communication module 204 to communicate with remote entities, computers, servers, etc. ;
• control module 206 connected to the valves V 1 to V3, to the pump 102 and to the pressure sensor 104, said module 206 being configured to control the valves and the pump, but also to recover the values of the measurements carried out by various sensors , in particular of the pressure sensor 104 or of environmental sensors (temperature, hygrometry, atmospheric pressure, etc.).
• Said module 106 can also comprise a power supply 206 either autonomous or connected to the mains (in particular via the electrical socket 39) and configured to convert the current and the input voltage into values compatible with the different elements of module 106 and/or device 1.
• a power supply 206 either autonomous or connected to the mains (in particular via the electrical socket 39) and configured to convert the current and the input voltage into values compatible with the different elements of module 106 and/or device 1.
• Said module 106 is also connected to the man-machine interface 5 (link not shown) and embeds in the memory 202, an operating system managing in particular the interface displayed on the screen 5a.
• said device 1 comprises a database 210, in particular stored in the memory 202, relating to the battery packs and to the various relevant parameters for carrying out a leak detection procedure adapted to the battery pack to be tested (for example under vacuum or under pressure).
• Said database 210 thus comprises a list of motor vehicle models and/or battery pack models in which each model (of battery pack and/or motor vehicle) is associated with a leak detection procedure.
• the database 210 includes for example for each battery pack listed at least one leak detection procedure specific to each of the elements of a battery pack.
• Each of the specific leak detection procedures thus comprises leak thresholds enabling the device 1 to determine whether the battery pack has a leak or not.
• Each of the leak detection procedures can thus include one or more of the following parameters: volume of the battery and/or of the thermal management system of the battery pack, duration t s tab and of the various stages of the leak test, pressure of test, rate of filling and/or emptying of the tested element of the battery pack, threshold of leakage.
• said database comprises a coefficient of flexibility or elasticity associated with at least one element of the battery pack (housing and/or thermal management system).
• the flexibility coefficient is for example a function V (P, t) linking the variation of the volume V of the tested element as a function of time t and/or pressure P, this reflects the element's tendency to vary in volume during a leak detection procedure.
• This function is all the more relevant to memorize (and to determine) as it is specific to each battery model and as it may present a non-linear character (due for example to the geometry and/or particular components of the battery pack).
• the variation of the volume can have consequences on the duration of the test, complicate the measurement of the leak and reduce the sensitivity, the volume, the pressure and the quantity of material in the tested object being brought to vary (these different quantities being linked together by the ideal gas law), and moreover the starting volume of the object also depends on the atmospheric pressure.
• one or more devices 1 can be connected to a computer network, for example the local network of a repair center.
• a device according to the invention can in particular clone and/or broadcast the parameters of its database to other devices connected to the same computer network.
• the pneumatic circuit of the device according to the invention comprises at least one flow limiter.
• said at least one flow limiter is arranged between the node N3 and the pressure sensor 104.
• a single flow limiter is sufficient to limit the flow in the pneumatic circuit, regardless of the leak detection procedure performed. by the device 1.
• each of the branches of the pneumatic circuit comprising a 1-way valve V1 or V2 comprises a flow limiter.
• the flow limiter notably allows the device according to the invention to vary the pressure in the tested object more finely, and therefore to have an actual pressure close to the desired pressure.
• the flow limiter is for example configured to have a maximum flow of 24 standard. litre/min, i.e. 0.4 standard. litre/ sec. However, it is advantageous for the maximum flow rate of the flow limiter to be lower than the maximum flow rate of the pneumatic circuit pump (the flow rate of the limiter must therefore be chosen according to the capability of the pump).
• Said device 1 can also be configured to measure the back pressure value relating to the battery pack tested.
• the measurement of the back pressure value is carried out at the start of filling (or emptying) of the part tested, therefore at the start of the leak detection procedure.
• the pressure is measured when the part is still empty, or during filling.
• backpressure is meant the resistance or the force opposing the desired flow of a fluid in conduits or a circuit, which leads to a loss by friction and a pressure drop.
• Said device 1 is in particular configured so that the measured counter-pressure value is taken into account during the filling/emptying of the parts tested.
• the pressure value displayed by I ⁇ HM 5 (and measured by the sensor 104) is thus the corrected value of the counter-pressure value, the corrected value therefore corresponding to the real pressure value.
• Said device 1 is also configured to communicate, for example via the communication module 204, with a remote server, in particular to download to a remote server one or more of the following data: the results of the leak tests and /or the leak test measurement signals.
• All of the data downloaded from the remote server can in particular be used to monitor the quality of the measurements and/or of the battery packs tested.
• Said downloaded data can also be used in the context of "machine learning” (or “machine learning” in English), in particular to optimize leak detection procedures (for example by reducing or optimizing stabilization times and/ or test, test pressure values, filling speeds, etc.).
• the parameters thus modified can then be downloaded by the device according to the invention so that the database relating to the leak detection procedures is updated.

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• 2021
  • 2021-07-27 FR FR2108139A patent/FR3125881B1/fr active Active
• 2022
  • 2022-07-13 EP EP22748362.5A patent/EP4378015A1/de active Pending
  • 2022-07-13 US US18/292,265 patent/US20240347779A1/en active Pending
  • 2022-07-13 CN CN202280052013.6A patent/CN117769780A/zh active Pending
  • 2022-07-13 WO PCT/EP2022/069683 patent/WO2023006434A1/fr active Application Filing

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