Method and system for managing battery devices in electric or hybrid vehicles including voltage measurement of cells connected to busbars - Patents.com

Abstract

The present invention relates to a management system and method that allows for better estimation of the voltages of cells connected to an interconnect bar in order to optimize durability and operation of the performance of a processing device.

Description

Summary of the Invention

[0001] The present invention relates to a method and a system for managing an electric battery device. The invention also relates to an electric or hybrid motor vehicle equipped with said system and / or implementing the aforementioned method.

[0002] Hybrid or electric motor vehicles are equipped with a battery device, also called simply "battery", capable of storing and supplying electrical energy to at least one element of the vehicle's electric drivetrain. These battery devices conventionally comprise a number of modules connected to each other by busbars to ensure electrical continuity of the device. Each of these modules comprises a number of electrochemical cells that may or may not be connectable to one of the busbars of the device.

[0003] During use, the battery device is controlled and monitored by a dedicated management system, called a "battery management system" or "BMS," to monitor and control the state and operation of the various cells of the battery device depending on the various usage modes, e.g., charging connected to the grid, discharging while driving, or regenerative braking charging. Such a system also enables direct or indirect estimation of parameters related to the battery device, such as the state of charge or "SOC," the state of health or "SOH," and / or any other parameters related to methods and functions for protecting the battery, e.g., safety methods aimed at keeping the device within predefined ranges of voltage and / or temperature values ​​to ensure durability.

[0004] Existing battery management systems have a master-slave architecture with, on the one hand, a master processing unit that is remote from the battery device and acts in particular as a control unit and / or computer, and, on the other hand, a number of "slave" elements that are equipped with voltage and temperature sensors and are located in the vicinity of the battery device to collect data that is transmitted to the master processing unit.

[0005] In current battery devices, each of the various modules is equipped with at least one slave element. If the number of cells of a module is less than the number of measurement channels of the slave element considered, the collection capacity of said element is not fully utilized, which leads on the one hand to an underutilization of the various slave elements and on the other hand to an increase in the cost and mass of the battery device due to the large number of slave elements required to equip all the modules of the device.

[0006] To address such problems, it is known to implement architectures of battery devices in which the same slave element is used to collect data from two different modules, with some of the measurement channels being dedicated to the first module and the remaining channels to the second module, as disclosed, for example, in Chinese application CN107482699. Such an architecture advantageously allows the various slave elements to be used at their maximum capacity and thus allows the number of slave elements to be reduced. Nevertheless, known management systems are not suitable for such architectures. In fact, the voltage measurements made by the slave elements on the cells to which the busbar is attached are biased by its presence. The measured voltage includes an additional voltage inherent to the busbar, resulting in an overestimation or underestimation of the voltage depending on the mode of use of the battery device. As a result, the estimates of the aforementioned parameters, such as SOH or SOC, are based on voltage values ​​that may be erroneous and any safe operation method of the battery device that uses these voltage values ​​may be inappropriately triggered.

[0007] The present invention is in this context and aims to provide a method and a system for managing a battery device that overcomes the aforementioned drawbacks, in particular to provide a precise estimate of the voltage values ​​of the various cells in order to optimize the operating conditions and durability of the battery device.

[0008] The present invention relates to a method for managing an electric battery device comprising a plurality of modules mounted in series, each module comprising a plurality of cells mounted in series, each module being directly electrically connected to at least one other module of the plurality of modules to form a modular pair, this connection being made by busbars connected at the cells of each module of the pair, the method comprising: measuring, by means of a slave element, a voltage specific to each cell, whether connected to a busbar or not, and measuring the temperature of each module, each temperature measurement being associated with one or more busbars connected to the module under consideration, each slave element comprising a number of measurement channels and connected to two modules of the pair under consideration; measuring a current flowing through the battery device; transmitting the measurements to a processing unit remote from the battery device; - estimating a voltage compensation value specific to each cell connected to a busbar, the compensation value corresponding to an estimated voltage of the busbar considered for each of said cells, the compensation value being estimated as a function of the temperature and the current of the module comprising the cell considered; estimating a corrected voltage value specific to each of the cells connected to the busbar by compensating the measured voltage values ​​with the estimated compensation value; adjusting and / or determining at least one limit parameter and / or state parameter of the operation of the battery device as a function of the estimated correction voltage and / or as a function of the measured voltage; Includes.

[0009] In particular, the compensation value may depend on the estimated resistance of the busbars connected to the cell under consideration.

[0010] In particular, the step of determining at least one limit parameter and / or at least one state parameter may comprise: determining a maximum cell-specific voltage value from a set formed by the measured voltage values ​​for the cells not connected to the busbars and the estimated corrected voltages for the cells connected to at least one busbar; determining a charging power that can be allocated to the battery device when in a charging mode as a function of a maximum voltage value, the charging power being limited if the maximum voltage value is equal to or greater than a maximum charging voltage threshold; and / or determining, as a function of a maximum voltage value, a regenerative charging power that can be allocated to the battery device when in a regenerative charging state, where the regenerative charging power is limited if the maximum voltage value is equal to or greater than a maximum regenerative charging voltage threshold; may include.

[0011] The method may further comprise determining a usage mode of the electric battery device from among a charging mode, a discharging mode, or a regenerative charging mode, and when the charging mode is detected, the method further comprises: Two moments t n-1 and n and calculating the variation in charging power between the observed charging powers respectively between Future moment t n+1 The substep of estimating the charging power is carried out at and the previously calculated power fluctuations and the instant t n a sub-step of detecting a future increase in charging power relative to the charging power observed in Future moment t n+1 The charging power is instantaneous t n limiting future charging power so as to be limited to be equal to or less than the charging power implemented at instant t n-1 and moment t nand releasing the limitation on the charging power when it is detected that the temperature fluctuation of at least one module between the The charging power is adjusted,

[0012] The step of determining at least one limit parameter and / or at least one state parameter may further comprise: determining a minimum cell voltage value from among the set comprising the measured voltage values ​​for cells not connected to the busbar, and from among the estimated correction voltages for cells connected to the busbar; determining a discharge power of the battery device as a function of a minimum voltage value, the discharge power being limited if the minimum voltage value is less than or equal to a minimum discharge voltage threshold; may include.

[0013] The step of determining the at least one limiting parameter and / or the at least one parameter may further comprise: Moment x the sub-step of estimating the resistance of each cell connected to the busbar in the battery device according to claim 1, comprising calculating an average resistance of the cells of the battery device not connected to the busbar as a function of the measured voltage for these cells and assigning such average value to each cell connected to the busbar; determining a discharge power that can be allocated to the battery device if the minimum voltage value is greater than a minimum discharge voltage threshold, the discharge power being determined as a function of the resistances of the various cells and the measured temperatures for each module; may include.

[0014] The step of determining the at least one limiting parameter and / or the at least one parameter may further comprise the sub-step of estimating a state of charge of various cells of the battery device, The state of charge of a cell not connected to the busbar is defined as a function of the measured voltage and the current specific to the cell, The state of charge of the cells connected to the busbar is defined as a function of the current specific to the cell, It may include sub-steps.

[0015] The invention also relates to a system for managing an electric battery device comprising a number of modules, each comprising a number of cells, each module being directly electrically connected to at least one other module of the plurality of modules to form a pair of modules, this connection being made by busbars connected at the cells of each module of the pair, the various modules being electrically connected to each other, the system comprising hardware and / or software elements implementing the management method according to the invention, the hardware elements comprising at least one slave element connected to each of the modules of the pair and capable of obtaining temperature and voltage measurements, a processing unit capable of receiving measurements from the at least one slave element, a memory unit and at least one current sensor.

[0016] The invention also extends to a hybrid or electric motor vehicle comprising at least one electric battery device comprising a plurality of modules each comprising a plurality of cells, each module being electrically connected to each of the other modules of the plurality of modules by a busbar in the vicinity of at least one cell, the vehicle further being equipped with a management system according to the preceding claims.

[0017] The invention also relates to a computer program product comprising program code instructions stored on a computer readable medium for carrying out the steps of the management method according to the invention when said program runs on a computer. Alternatively, such a computer program product can be downloaded from a communication network and / or stored on a computer readable data medium and / or executed by a computer, such program product comprising instructions which, when said program is executed by a computer, cause said computer to carry out the method disclosed above.

[0018] The invention also relates to a computer-readable data storage medium storing a computer program comprising program code instructions for carrying out the method according to the invention, or a computer-readable storage medium comprising instructions which, when executed by a computer, cause the computer to carry out the secure method.

[0019] Finally, the invention relates to a data-carrier signal carrying the computer program product disclosed above.

[0020] Further details, features and advantages will become more clearly apparent on reading the following detailed description, given by way of non-limiting indication, in relation to various exemplary embodiments illustrated in the following figures: [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 illustrates a schematic diagram of an embodiment of a vehicle equipped with a system for managing a battery device. [Diagram 2] 1 is a flow chart of an exemplary embodiment of a method for managing a battery device. [Diagram 3] 3 is a flow chart of a particular illustrative embodiment of a method of the battery device shown in FIG. 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] 1 shows a schematic representation of an electric or hybrid motor vehicle 1. The vehicle 1 can be of any type, i.e. a passenger car, a utility vehicle, a truck or a bus. Furthermore, the vehicle 1 can be an autonomous or a non-autonomous vehicle.

[0023] The vehicle 1 is equipped with an electric battery device 2, also called a "battery," "electrical energy storage device," or "battery pack," configured to supply electric energy to one or more elements of an electric drivetrain (not shown) of the vehicle 1. For example, the electric battery device 2 may supply an electric motor.

[0024] The battery device 2 comprises a number of modules 3 mounted electrically in series. Each module 3 comprises a number of electrochemical cells 4 mounted in series within the same module. The various modules 3 are electrically connected to one another by busbars 5, which can be made of copper, for example. Each module is directly electrically connected to at least one other module of the number of modules 3, in particular to an adjacent module within the battery device 2, to form a pair of modules 3. The term "directly connected" is understood to mean that these modules 3 are connected to one another by a single busbar 5, without another busbar or another module being electrically interposed between them.

[0025] Thus, a battery device 2 comprising k modules 3 may include, in a non-limiting manner, k-1 bus bars 5 enabling successive or adjacent modules 3 to be connected to one another. Each module of the device thus comprises at least one cell 4a connected to a bus bar 5 and at least one cell 4b not connected to such a bar. In the illustrated example, for the sake of clarity, only two different modules 3 forming a pair and each comprising eight cells 4 are shown. It is understood that such a depiction is in no way limiting and that the device may include more modules 3 and / or a different number of cells 4.

[0026] The vehicle 1 is also equipped with a system 6 for managing the battery device 2. The management system 6 comprises hardware and / or software elements implementing a management method 100 disclosed below. The hardware elements comprise a processing unit 7 and one or more slave elements 8 comprising a number of temperature and voltage measurement channels. The system may further comprise a memory unit 9 and at least one current sensor 10 for the current flowing through the battery device 2.

[0027] The management system 6 is organised according to a "master-slave" architecture, in which a processing unit 7, also called master processing unit 7, is remote from the battery device 2 and is configured to receive data from various "slave" elements 8, comprising in particular voltage and temperature sensors, in order to carry out processing.

[0028] The processing unit 7 comprises at least one computer with hardware and software resources, more specifically at least one processor or microprocessor. The processing unit 7 cooperates with the memory unit 7, the slave elements 8 and the sensors 10 and assumes a "master" function in the architecture of the management system 6. The processing unit 7 is capable of executing instructions for implementing a computer program.

[0029] The management system 6 comprises a number of voltage and temperature sensors 8 arranged in the vicinity of the modules 3 of the battery device 2. Such sensors act as "slave" elements in the system. Each slave element 8 comprises a number of measurement channels 11. In particular, each of the one or more slave elements 8 comprises more channels than the number of cells 4 contained in each module 3 of the battery device 2. In the system according to the invention, each slave 8 is configured to be able to perform measurements on two different modules of the plurality of modules 3, in particular on modules 3 of the considered pair disclosed above. In this case, a first slave element 8 comprising at least one voltage and temperature sensor comprises 12 channels, 8 of which are dedicated to the 8 cells 4 of the first module 3' of the pair and the remaining 4 are connected to the 4 cells 4 of a second module 3" of the pair different from the first module 3'. A similar second slave element 8, partially shown, is connected to the remaining 4 cells 4 of the second module 3" and the other 8 channels are connected to the third module 3'". It is also understood that said second module 3″ is connected to said third module by a busbar 5, so that the second and third modules form a pair connected by their own busbar 5. According to one non-limiting exemplary embodiment, the last cell 4 of the module 3′ is connected to a busbar, which is itself connected to the first cell 4 of the second module 3″. The terms “first” and “last” are understood in this specification to mean the first and last cell in the series electrical assembly of the considered modules. Similarly, the last cell 4 of the second module 3″ is connected to the first cell 4 of the third module 3′″. Such a principle is reproduced mutatis mutandis for all modules 3 of the battery device 2.

[0030] Due to the continuity of the measurements, it is known that if a slave element is used to manage two different battery modules 3, the voltage measurements obtained from the cells connected to at least one busbar 5 will contain an additional voltage corresponding to the voltage inherent to said busbar 5. This is evident in the case of the "last cell" 4 disclosed above. This results in an erroneous measurement of the voltage of the cell 4a connected to the busbar. In fact, the busbar 5 has a higher resistance, which leads to a voltage difference between the two battery cells 4a connected to both ends of said bar. As will be further disclosed below, the additional voltage of the busbar 5 depends on its resistance, which in turn is determined by the voltage difference between the two battery cells 4a connected to both ends of said bar. The size and composition of the busbar 5; the quality of contact and clamping between the module and the busbar, The temperature of the busbar 5, and Aging condition of the surface of the busbar 5 may vary according to

[0031] The magnitude of the additional voltage due to the busbars 5, in other words the difference between the measured and the actual voltage of the cells 4a connected to said bars, influences the operation of the battery device 2 in its various modes of use or operation. For example, when charging the battery device 2, such additional voltage induces an overestimation of the measured voltage for the cells 4 that are not connected to at least one busbar 5. Conversely, when discharging the device, an underestimation of this voltage is observed. In particular, in the case of charging, for example "fast charging" or "ultra-fast charging", the higher the current used, the higher the additional voltage.

[0032] These erroneous measurements of the voltages of the cells 4a connected to at least one busbar 5 also affect various parameters associated with the battery device 2, such as its power, its state of charge, or its state of health, as disclosed above, and also affect the operation of various systems that regulate the use of the battery device 2 based on such parameters, as further disclosed below in connection with the present method, which in turn affects the utilization of the performance capabilities of the battery device 2.

[0033] In this sense, an embodiment of a management method 100 allowing a more accurate estimation of these voltages, as well as various parameters related to the battery device 2, is described below with reference to FIGS.

[0034] In general, the management method 100 first calculates a voltage V m_cell These measurements are carried out by slave elements 8. As disclosed above, each slave element 8 comprises a number of measurement channels 11 and is connected to at least two different modules 3. The number of measurement channels of the sensor considered is significantly greater than the number of cells 4 specific to the module 3 to which it is connected.

[0035] The method comprises: determining a temperature T mod Then, each temperature measurement T mod is associated with one or more busbars 5 connected to the module 3 under consideration in order to allow for the estimation of the temperature of the busbars 5 based on the heating of the module, as will be further disclosed below. In particular, for each busbar 5 under consideration, an associated measured temperature T mod is specific to the pair of modules 3 to which it connects, the module with the cell having the incorrect voltage due to the presence of said busbar 5. In this case, in the example disclosed above, each busbar 5 provides a measured temperature T mod With regard to the illustrated modules, in the pair formed by a first module 3' and a second module 3'', the busbar 5 is associated with the temperature of the first module 3'.

[0036] Voltage V m_cell and temperature T modThe measurements can be made in real time, i.e. continuously, or alternatively at preprogrammed regular time intervals. The temperature and voltage measurements can be made simultaneously or sequentially relative to one another.

[0037] The management system 6 measures the voltage I flowing through the battery device 2 by means of one or more current sensors 10. m The step E03 of measuring the current is also carried out. The current is evaluated relative to the scale of the battery device 2.

[0038] Voltage V m_cell and temperature T mod For the measurement of current I m can be measured in real time or, alternatively, at regular preprogrammed time intervals. Current can also be measured simultaneously or consecutively with the temperature and / or voltage measurements.

[0039] The system then detects the voltage V m_cell and temperature T mod The same applies to the current measurement I m also applies.

[0040] The processing unit 7 then calculates a voltage compensation value V b_est Such a compensation value V b_est corresponds to the estimated voltage specific to the considered busbar 5 for each of said cells 4a. The compensation value is the current I m and the resistance R of the busbar 5 connected to the cell 4a est and in particular the measured temperature T of the module 3 comprising the cell under consideration. mod , the temperature of the busbar 5 cannot be measured directly. In this case, a voltage compensation value V b_est is the current I m and the resistance R of the busbar connected to the cell 4a under consideration.est corresponds to the product of the estimated value of

[0041] It is therefore advantageously possible to take into account variations in the behavior of cells 4 of the same module 3, in particular variations in the behavior of one or more cells 4a connected to one or more busbars 5 relative to cells 4b that are not connected to a busbar 5.

[0042] Estimated resistance R est Specifically, it can be defined as follows: (1)R est =R ref ×(1+α1×(T mod -T ref ))+R cont ×(1+α2×(T mod -T ref )) Where: R est is the estimated resistance of the busbar 5. ref is a fixed reference temperature value. In this case, in a non-limiting manner, this temperature is 20° C. ref is the reference temperature T ref is a fixed value for estimating the resistance of the busbar 5 at T. This value can be predefined or calibrated and stored in the memory unit 9. This value is determined depending on the dimensions of the busbar 5, whose resistance increases with its size and increases depending on its composition. mod is the measured temperature of the module to which the considered busbar 5 is connected. Therefore, the measured temperature T mod and reference temperature T ref The difference between R and R represents heating due to, for example, use or charging of the battery device 2. cont is the estimated fixed value of the contact resistance existing between the module under consideration and the busbar 5 connected to it. This value can be predefined or calibrated and stored in the memory unit 9. The contact resistance R cont is defined as a function of the quality of the contact and clamping between the busbar 5 and the module under consideration. α1 is the reference resistance R refIn particular, α1 is a guide coefficient for the line that represents the change in reference resistance as a function of temperature and is pre-calibrated. α2 is the change in contact resistance R as a function of temperature. cont is a fixed value which represents the increase in the contact resistance as a function of temperature. Like α1, it is a guide coefficient of the line which represents the change in contact resistance as a function of temperature and is pre-calibrated. The values ​​α1 and α2 are defined before carrying out the method, in particular before assembling the vehicle, and are stored in the memory unit 9 so as to be accessible to the processing unit 7.

[0043] As disclosed above, the resistance R of the busbar 5 est varies depending on parameters such as its size, its composition, the quality of the contact and clamping between the module and the busbar, the temperature of the busbar 5 or even the state of aging of the surface of the busbar 5. The formula disclosed above allows the resistance specific to the considered busbar 5 to be estimated and, as a result, the resulting additional voltage to be estimated by simple multiplication with the measured current value. The completed estimation therefore takes these parameters into account in order to carry out an under-estimation of the voltage value in order to fully or partially correct the positive excess in the case of charging currents and the negative excess in the case of discharging currents of the measured voltage due to the considered busbar 5. In fact, as will be further disclosed later, it is essential that the compensation values ​​are not overestimated at the risk of generating overvoltage or undervoltage conditions that may affect the durability of the various cells 4.

[0044] Thus, the management system 6 determines a unique correction voltage value V for each of the cells 4 connected to the busbar 5. corr It is possible to obtain (E06) an estimate of the measured voltage V . The estimated corrected voltage corresponds to the measured voltage of the cell corrected to ignore the additional voltage inherent in the busbar 5. Such a voltage is advantageously calculated by subtracting the measured voltage V m_cell This better represents the actual situation, i.e. the actual voltage, of the considered cell 4 than the estimated corrected voltage V corr is defined as follows: (2) V corr =V m_cell -R est ×Im =V cell -V b_est Where: R est is the estimate of the resistance of the busbar 5 previously calculated for the cell 4a connected to the busbar 5. The value R est It should be noted that V is zero for the cell 4b that is not connected to the busbar 5. m_cell is the pre-measured cell voltage and I m is the measured current.

[0045] Optionally, as shown in Fig. 3, the system can execute, simultaneously with or after the previously disclosed steps, a step E07 of determining the usage mode of the electric battery device 2 from among a charging mode, a discharging mode or a regenerative charging mode. The term "discharging" is understood to mean, for example, that the vehicle 1 is in a driving phase. The term "regenerative charging" is understood to mean recovering the electric energy resulting from the braking of the vehicle 1. For example, the processing unit 7 receives a signal indicating the usage mode of the battery device 2 at the moment t at which the method according to the invention is performed.

[0046] The management system 6 then determines the determined correction voltage V corr and / or as a function of the measured voltage V m_cell , then performs a step E08 of adjusting and / or determining at least one limiting parameter of the operation of the battery device 2 and / or at least one parameter for assessing the state of said battery device. In particular, such a parameter may be directly or indirectly linked to one of the usage modes of the battery device 2. Such a step may in particular correspond to the adjustment or updating of existing values ​​of the parameters taken into account, resulting for example from a previous cycle of executing the method according to the invention and previously stored in the memory unit 9 or in any other memory element of the vehicle 1.

[0047] 2 and 3 show the determination E08 of parameters related to the "charging" or "regenerative charging" mode. The "charging" mode can equally relate to normal charging situations and to fast or ultra-fast charging situations.

[0048] Conventionally, during a charging or regenerative charging phase, safety methods may make it possible to limit, i.e. reduce, the allocated charging power relative to a maximum capacity. These safety methods, also known as “derating” methods, are implemented in order to maintain the temperature and / or voltage of the various cells 4 within a given range of compatible values. Such methods are intended to avoid overvoltage or overheating situations, in particular to ensure the durability of the battery device 2. Thus, these methods are intended to limit the measured voltage V of the cells 4. m_cell As a function of the charging power P c Or regenerative charging power P c_regen is adapted, said power being limited as soon as the cell's voltage is equal to or greater than a predefined maximum power threshold specific to the state of charge considered.

[0049] Therefore, the charging power P c Or regenerative charging power P c_regen is the temperature T under normal conditions mod and the measured voltage V m_cell can be defined based on a 2D map as a function of V, i.e., when the measured temperature and voltage are within the tolerance range, and when the measured voltage V m_cell If V is greater than the maximum power threshold, the power is reduced. For the architecture of the battery device 2 disclosed above, the voltage measurements V of the cells 4 connected to the busbars 5 are m_cell is incorrect. In particular, when in charging mode or regenerative charging mode, the measured voltage V m_cell is overestimated with respect to the actual voltage value of the considered cell, and the size of such overestimation varies as a function of the considered busbar. As a result, the charging power P c Or regenerative charging power P c_regenThe additional voltage on busbar 5 included in this measurement causes safety methods that limit charging to be triggered sooner than necessary, even though the actual voltage on the cell is within tolerance. This increases the required charging time, but also unduly limits the performance capabilities of the vehicle.

[0050] Within the context of the present invention, the method 100 comprises: m_cell A more realistic corrected estimated voltage V corr Charging power P based on c Or regenerative charging power P c_regen Based on the determination, such shortcomings can be limited.

[0051] In this sense, the step E08 of adjusting and / or determining at least one parameter related to the battery device 2 may firstly comprise a substep E091 of determining, by the processing unit 7, a maximum voltage value in the battery device 2. Such a maximum value is determined by the measured voltage value V for the cell 4b not connected to the busbar 5. m_cell and the pre-calculated estimated corrected voltage V for the cell 4a connected to the busbar 5. corr The set is determined from the set formed by

[0052] In particular, such a sub-step can be defined as follows: TIFF2025501132000002.tif11170, where V max is the maximum voltage determined for the scale of the battery device 2. V m_cell is the voltage measured for each cell, whether it is connected to the busbar 5 or not. R est is the estimated resistance of the considered busbar 5 calculated previously, and for a cell 4b that is not connected to a busbar 5, such value is zero. I mis the current flowing through the battery device 2, and the product of the estimated resistance and current defines an estimate of the additional voltage inherent to the busbar 5, as explained above. nbr_cell is the number of cells 4 contained in the entire battery device 2.

[0053] The method 100 then determines the maximum voltage value V max , in anticipation of the execution of the charging mode, or alternatively, for the charging mode implemented when executing the method according to the invention, the charging power P c The processing unit 7 may include a substep E092 of determining the defined maximum voltage value V max The maximum allowed charging voltage threshold S c_max Compare with the determined maximum voltage value V max If is equal to or greater than the threshold, the allocated charging power P c is in particular limited according to safety methods also known as "derating" methods.

[0054] Calculated maximum voltage value V max is less than said threshold, the processing unit 7 of the management system 6, or alternatively any other processing module equipped in the vehicle 1 and in communication with the processing unit 7, determines the charging power P that can be allocated to the battery device 2 when in the charging mode. c In other words, the processing unit 7 can define the maximum voltage V max is within the previously defined range of acceptable voltage values ​​that are lower than the maximum charging voltage threshold, c A similar principle applies mutatis mutandis to the regenerative charging power in the regenerative charging mode.

[0055] As a non-limiting example, the charging power P c is a calculated maximum voltage V based on a 2D map stored in the processing unit and specific to the usage mode of the battery device 2 being considered. max and the measured temperature of the module, T modAccording to a particular example, the previously measured temperatures T of the various modules can be defined as a function of mod The minimum and maximum temperatures are extracted from the 2D map, and then the two charging powers P c The lowest of these two powers is then used to define the charging power P c It can be applied as:

[0056] According to a particular embodiment shown in FIG. 3, the method can also be configured to limit or even prevent situations that generate voltage and power oscillations when the charging mode is implemented. Indeed, it is known that the less charged a cell is, the lower its voltage and the greater the allocated charging power. When a cell 4 starts to charge, its voltage rises and the power allocated to the charge decreases. Such a drop in charging power consequently causes a drop in the measured voltage, including the additional voltage of the busbar 5 in the cell 4a connected to such a bar. The charging power is then increased, resulting in a new rise in voltage. Such a sequence is repeated and then the phenomenon of voltage oscillations is observed, which can take non-negligible values ​​of tens of kilowatts.

[0057] In order to overcome the aforementioned drawbacks, if a charging mode is detected in step E07, i.e. if such a mode is being executed, the method and the system according to the invention can advantageously be configured to limit the possibility of increasing the charging power when said power has previously been reduced. In this sense, the method comprises the steps of: Past Moments n-1 and the present moment t n The observed charging power P c_n-1 , P c_n Fluctuation in ΔP c1 a substep E101 of calculating Future moment t n+1 Charging power P c_n+1 and a substep E102 of estimating the previously calculated power variation ΔP c1 At that moment,n The charging power P observed c_n and a substep E103 of detecting a future increase in charging power for Such an estimation may, for example, be based on a 2D map, as disclosed above, Moment n+1 At the moment when the charging power is n Charging power P c_n The future charging power P c_n+1 This can be accomplished in a substep E104 of restricting

[0058] The method according to the invention is particularly characterized in that at least one module T of the battery device 2 mod At moment t n-1 and n Between the threshold T s Temperature fluctuation ΔT greater than m is detected (E105), the method is also configured to be able to release the limitation of the charging power. Indeed, it is also known that an increase in the charging power may result from the conventionally observed heating of the battery device 2 due to the flow of current through the cells 4. The method therefore includes a step of determining the time t specific to the various modules. n-1 and n At least one module T between mod Temperature change ΔT in m Such calculation is carried out by the processing unit 7 on the basis of measurements obtained by the slave element 8 of the battery device 2. The method then involves the calculation of these various values ​​relative to a threshold T s By way of non-limiting example, such a threshold value may be in the range of 1 to 5° C. m is the threshold T s If the charging power P is less than 0.05V, the estimated future power increase is due to voltage fluctuations rather than temperature. c is the moment t n Conversely, the temperature change ΔT mIf the charging power P is greater than the threshold, the estimated future power increase is at least partially due to temperature fluctuations of the battery device 2. c may then increase. Potential oscillations may then be generated, but these have low values ​​compared to those observed due to voltage fluctuations.

[0059] 2 and 3 also show the determination of parameters related to the discharge mode of the battery device 2, for example, when driving the vehicle 1. As disclosed with respect to the state of charge, vehicles conventionally implement safety or "derating" methods when discharging the battery device 2, in particular to keep the temperature and / or voltage of the various cells 4 within appropriate value ranges, in this case to prevent low-voltage situations. Such safety methods use the previously disclosed charging power P to limit, i.e., reduce, the discharge power as soon as the cell voltage falls below a predetermined minimum voltage threshold specific to the discharge mode of the battery device 2. c Apart from this, it allows the discharge power to be adapted as a function of the voltage of the cell 4. As disclosed above, if the measurement of the voltage of a cell 4a connected to the busbar 5 is incorrect due to the voltage of the busbar 5, these safety methods will be triggered earlier than necessary, even though the actual voltage of the cell is within the tolerance range.

[0060] The method 100 according to the invention is particularly adapted within the context of such a safety method to measure the measured voltage V m_cell Discharge power P based on estimated correction voltage, not based on de Thus, the step E08 of adjusting and / or determining at least one limiting parameter and / or at least one state parameter determines a minimum voltage value V among the various voltage values ​​of the cells 4 of the battery device 2. min A substep E093 of determining a minimum value V min is the measured voltage V of cell 4a that is not connected to busbar 5 m_cell and the estimated corrected voltage V of the cell 4a connected to the busbar 5.corr The metric is defined from a set of values ​​consisting of

[0061] In particular, the minimum voltage value is defined as follows: TIFF2025501132000003.tif11170, where R est is the previously estimated resistance of the busbar 5 considered, and for the cell 4b not connected to the busbar 5, such a value R est is zero. V m_cell is the measured voltage of each cell, whether it is connected to the busbar 5 or not. I m is the current flowing through the battery device 2. nbr_cell is the number of cells 4 contained in the entire battery device 2.

[0062] The method then proceeds to determine the minimum voltage value V min As a function of de The processing unit 7 may include a substep E094 of determining the determined minimum voltage value V min The minimum permitted discharge voltage threshold S d_min Compare with.

[0063] The minimum voltage value V min is the minimum permitted discharge voltage threshold S d_min , i.e. if the minimum voltage in the battery device 2 is within an allowed range of voltage values ​​and no safety measures are required, the processing unit 7 of the management system 6, or alternatively any other processing module equipped in the vehicle 1, determines, in a known manner, a discharge voltage P 2 which can be assigned to the battery device 2 on the basis of a 2D map depending on the state of charge (SOC) and the temperature of the battery device 2. de In particular, the charging power P c The principles for defining power as a function of minimum and maximum temperatures, as disclosed above with respect to, apply mutatis mutandis.

[0064] Minimum voltage value V min If is less than or equal to the threshold, the allocated discharge power S d_min In other words, the estimated voltage V of cell 4a is limited to a maximum capacity so that triggering of existing safety methods is performed at a voltage value that is more representative of the actual voltage of cell 4 of the battery device 2. corr Then, the discharge voltage P de is defined as a function of the temperature and resistance of cell 4, and as such is a function of the measured voltage V m_cell As a result, the method according to the invention provides a better evaluation of the estimated resistance taking into account the additional voltages of the various busbars 5, and thus the discharge power P de Such a principle applies more as the cells 4 age and their resistance, and therefore the resistance inherent in the busbars 5, increases. In this sense, the step E08 of adjusting and / or determining at least one parameter of the operation of the battery device 2 is performed based on the time t x Each cell 4a connected to the busbar 5 has a specific resistance R d_est Such a resistance R may be estimated by a substep E095. d_est is the average resistance R of the cells 4b of the battery device 2 that are not connected to the busbar 5 m The resistance of the cell is estimated by calculating m_cell and current I m It is calculated as a function of

[0065] Then, this average resistance R m A value of is assigned to each of the cells 4a connected to the busbar 5. The processing unit 7 then calculates the resistances of the various cells 4a, 4b, which may or may not be connected to the busbar 5, and the temperatures T measured for each module 3. mod Discharge voltage P of battery device 2 as a function of de As a non-limiting example, a step E096 of determining the discharge power P deis defined based on the 2D map as a function of the temperature of the module and / or the battery device, the state of charge of the battery device 2, and the maximum resistance value, as disclosed above, among the estimated resistance values ​​for the cells 4 a connected to the busbar 5, and among the measured voltage V for the cells 4 b not connected to the busbar 5. m_cell and current I m The resistance is determined from the calculated resistance based on

[0066] The resistance value R thus obtained for the cell 4a connected to the busbar 5 d_est is more representative of reality and avoids the inclusion of additional voltages, in this case resistances, inherent in the busbar 5. In this case, such a method is appropriate since, for the scale of the battery device 2, the number of cells 4a connected to the busbar 5 is strictly less than the number of cells 4b not connected to the busbar.

[0067] The step E08 of adjusting and / or determining at least one parameter of the operation of the battery device 2 is c_regen As disclosed with respect to the charging and discharging modes, the vehicle may also be configured to implement safety or "derating" methods during the regenerative charging phase in order to maintain the temperatures and / or voltages of the various cells 4 within appropriate value ranges.

[0068] In this case, these safety methods are performed when the cell voltage exceeds the maximum allowed regenerative charging voltage threshold S regen_max As soon as the regenerative charging power P c_regen In order to limit, i.e., reduce, the regenerative charging power P c_regen Such a threshold S regen_max is the maximum charging voltage threshold S c_max It should be noted that the values ​​of , ...

[0069] The calculated maximum voltage value V, calculated according to formula (3) disclosed above in particular for the charging mode.max is lower than the threshold value, i.e., the maximum voltage value V max If lies within the normal range, the processing unit 7 of the management system 6, or alternatively any other processing module, determines the charging power P that can be allocated to the battery device 2 as a function of the 2D map. c_regen The above description provided with respect to the discharge mode applies mutatis mutandis to the 2D map considered, which may be defined as a function of the temperature, the state of charge and the maximum resistance value of the module and / or the battery device, as disclosed above, by way of non-limiting example.

[0070] The determined maximum voltage value V max is the threshold S regen_max If it is greater than or equal to 1000V, i.e. safety or "derating" methods must be implemented, the regenerative charging power P c_regen is restricted.

[0071] As disclosed above, the resistance of a cell 4 increases with age. The same applies to the busbar 5. Thus, the magnitude of the overestimation or underestimation of the voltage or resistance values ​​tends to increase with the age of the cell 4. Conventionally, the ageing of a cell 4 can be estimated by determining the intrinsic resistance state ER of the cell 4. The resistance state ER is obtained by calculating the resistance of the cell based on the voltage and the measured current and then comparing this value with an initial resistance value corresponding to the resistance of a new cell stored in the memory unit 9 or any other memory element of the vehicle 1 in order to determine the rate of increase of the internal resistance of the cell. This principle is not suitable for cells 4 connected to a busbar 5 due to the aforementioned drawbacks. According to the invention, the calculation of the resistance state ER is performed by calculating the estimated resistance R of the cell 4a connected to the busbar 5. d_est with the initial resistance of the cell 4 connected to the busbar.

[0072] The resistance state estimated in this way is more representative of the reality of the battery device 2. The resistance state ER can also be used to calculate or estimate various operating parameters of the battery device 2, such as the power, and thus the method according to the invention provides a more reliable assessment of the state of the battery device 2.

[0073] The state of charge (SOC) of the battery device 2 is also a state parameter of the battery device 2 used in many operations of the vehicle 1, such as determining the autonomy, power or duration of charging. Conventionally, the SOC can be estimated by a Kalman filter based on the measured voltage and current. As disclosed above, if the voltage measured at the cell 4a connected to the busbar 5 is incorrect, the SOC value will also be incorrect, which generates a non-negligible impact on the scale of the vehicle 1.

[0074] Furthermore, the method 100 according to the invention can advantageously be adapted to determine a SOC that is more representative of reality. Thus, the step E08 of adjusting and / or determining at least one parameter of the battery device 2 can include a substep E097 of estimating the state of charge of the various cells 4 of the battery device 2, in which: The state of charge of the cell 4b that is not connected to at least one busbar 5 is determined, in particular by a Kalman filter, from a measured voltage V m_cell and current I m is defined as a function of The state of charge of a cell 4a connected to at least one busbar 5 is defined as a function of the current specific to the cell 4a as follows: TIFF2025501132000004.tif12170, where SOC t is the state of charge of the cells connected to the busbar 5 at the instant t, and I m is the measured current flowing through the cell, C is the capacitance of the cell, and Δt is the sampling time, for example in hours.

[0075] Thus, the method according to the invention can be executed in such a way that during step E08 of adjusting and / or determining at least one limit and / or state parameter of the operation of the battery device 2, all or some of the various aforementioned parameters can be estimated and associated with at least one operating state of the battery device 2. Said parameters can also be associated with other functions of the battery device 2 and can be transmitted to various systems equipped on the vehicle 1, such as a system for locating the vehicle 1 in the road infrastructure or a driving assistance system. According to a preferred embodiment, the various aforementioned parameters are estimated independently of how the vehicle 1 is used when executing the method, in other words independently of the mode of use, which can be optionally detected when executing the method. The parameters thus estimated, which relate to a mode of use that is not being executed, can be stored in the memory unit 9, whereas the parameters related to a mode that is being executed can be stored and / or directly applied to the current use.

[0076] Thus, the method and system according to the invention advantageously allow a battery device management that is more adapted to its architecture, which not only optimizes durability but also takes advantage of the performance capabilities of the processing device, and further improves the operation of auxiliary systems equipped in the vehicle and based on parameters related to the battery device.

[0077] However, the present invention is not limited to the means and modes described and illustrated herein, but extends to any equivalent means or modes, and any technically operable combination of such means, so long as they ultimately fulfill the functionality described and illustrated in this document.

Claims

1. A method (100) for managing an electric battery device (2) comprising a plurality of modules (3) mounted in series, each module comprising a plurality of cells (4) mounted in series, each module (3) being electrically connected directly to at least one other module (3) of said plurality of modules (3) to form a module (3) pair, said connection being made by bus bars (5) connected at the cells (4a) of each module (3) of said pair, said management method (100) comprising: Each cell (4, 4a, 4b) is supplied with a specific voltage (V) by the slave element (8), regardless of whether it is connected to the busbar (5) or not. ｍ＿ｃｅｌｌ ) of each module (3) (T ｍｏｄ ) step (E02), wherein each temperature measurement (T ｍｏｄ a step (E02) in which a slave element (8) is associated with one or more of the busbars (5) connected to the module under consideration, each slave element (8) comprising a plurality of measurement channels (11) and connected to two of the modules (3) of the pair under consideration; The current (I ｍ ) measuring step (E03); a step (E04) of transmitting said measurements to a processing unit (7) remote from said battery device (2); A voltage compensation value (V) specific to each cell (4a) connected to the busbar (5) ｂ＿ｅｓｔ ) and a step (E05) of estimating said compensation value (V ｂ＿ｅｓｔ ) corresponds to the estimated voltage of the busbar (5) considered for each of the cells (4a), and the compensation value (V ｂ＿ｅｓｔ ) is the temperature (T ｍｏｄ ) and the current (I ｍ Step (E05), wherein the value is estimated as a function of The measured voltage value (V ｍ＿ｃｅｌｌ ) to the estimated compensation value (V ｂ＿ｅｓｔ ) to obtain a corrected voltage value (V) specific to each of the cells (4a) connected to the busbar (5). ｃｏｒｒ ) and a step (E06) of estimating The estimated correction voltage value (V ｃｏｒｒ ) and / or as a function of the measured voltage value (V ｍ＿ｃｅｌｌ and a step (E08) of adjusting and / or determining at least one limit parameter and / or status parameter of the operation of said battery device (2) as a function of Including, Management method (100).

2. The compensation value is calculated by dividing the estimated resistance (R ｅｓｔ ) and the estimated resistance is defined as: R ｅｓｔ =R ｒｅｆ ×(1+α １ ×(T ｍｏｄ -T ｒｅｆ ))+R ｃｏｎｔ ×(1+α ２ ×(T ｍｏｄ -T ｒｅｆ )) where: T ｒｅｆ is a fixed reference temperature value, R ｒｅｆ is the reference temperature value T ｒｅｆ a fixed value for estimating the resistance of the busbar (5) based on the dimensions and composition of the busbar (5) at T ｍｏｄ is the temperature of the module to which the considered busbar (5) is connected, R ｃｏｎｔ is the estimated fixed value of the contact resistance existing between the module under consideration and the busbar (5) connected to it, α １ is a fixed value representing the increase in reference resistance as a function of temperature, α ２ is a fixed value representing the increase in contact resistance as a function of temperature; The management method (100) of claim 1.

3. said step (E08) of determining at least one limit parameter and / or at least one state parameter may comprise: The measured voltage value (V ｍ＿ｃｅｌｌ ) and the estimated corrected voltage (V) for the cell (4a) connected to at least one busbar (5). ｃｏｒｒ ) and the maximum voltage value (V ｍａｘ a substep (E091) of determining The maximum voltage value (V ｍａｘ ) as a function of the charging power (P ｃ a substep (E092) of determining the maximum voltage value (V ｍａｘ ) is the maximum charging voltage threshold (S ｃ＿ｍａｘ ) or more, the charging power (P ｃ ) is limited, and / or As a function of the maximum voltage value, the regenerative charging power (P ｃ＿ｒｅｇｅｎ ), wherein said maximum voltage value is a maximum regenerative charging voltage threshold (S ｒｅｇｅｎ＿ｍａｘ ) or more, the regenerative charging power (P ｃ＿ｒｅｇｅｎ ) is restricted, sub-step (E098); Including, The management method (100) of claim 2.

4. The maximum voltage value is defined as follows: where: R ｅｓｔ is the estimated resistance of the considered busbar, V ｍ＿ｃｅｌｌ is the voltage measured for each cell, whether connected to the busbar (5) or not, I ｍ is the current flowing through the battery device (2), nbr_cell is the number of cells (4) contained in the entire battery device (2); The management method (100) of claim 3.

5. A management method (100) comprising a step (E07) of determining a usage mode of the electric battery device (2) from among a charging mode, a discharging mode or a regenerative charging mode, said method comprising, when a charging mode is detected, Two moments t ｎ－１ and ｎ The charging power (P ｃ＿ｎ , P ｃ＿ｎ－１ ) fluctuation of charging power (ΔP ｃ１ ) and a sub-step (E101) of calculating future moment t ｎ＋１ Charging power (P ｃ＿ｎ＋１ ) and the substep (E102) of estimating the power fluctuations (ΔP ｃ１ ) and said instant t ｎ The charging power (P ｃ＿ｎ a substep (E103) of detecting a future increase in said charging power relative to The moment t ｎ＋１ The charging power (P ｃ＿ｎ＋１ ) at the moment t ｎ The charging power (P ｃ＿ｎ ) so as to be limited to be equal to or less than the future charging power (P ｃ＿ｎ＋１ ), wherein the step (E104) limits the instant t ｎ－１ and the instant t ｎ At least one module (T ｍｏｄ ) temperature fluctuation (ΔT ｍ ) is a predetermined temperature threshold (T ｓ Step (E104), when it is detected that the charging power is greater than the limit (E105), the limit on the charging power is released; performing a step (E10) of adjusting the charging power, including The management method (100) according to claim 3 or 4.

6. said step (E08) of determining at least one limit parameter and / or at least one state parameter may comprise: For the cells (4) not connected to a busbar (5), from the set including the measured voltage values, and for the cells (4) connected to a busbar (5), the estimated corrected voltage (V ｃｏｒｒ ) among the minimum voltage value of the cell (V ｍｉｎ a substep (E093) of determining The minimum voltage value (V ｍｉｎ ) as a function of the discharge power (P ｄｅ a substep (E094) of determining the minimum voltage value (V ｍｉｎ ) is the minimum discharge voltage threshold (S ｄ＿ｍｉｎ ) or less, the discharge power (P ｄｅ ) is restricted, sub-step (E094); Including, The management method (100) according to any one of claims 2 to 4.

7. The minimum voltage value is defined as follows: where: R ｅｓｔ is the estimated resistance of the considered busbar, V ｍ＿ｃｅｌｌ is the voltage measured for each cell, whether connected to the busbar (5) or not, I ｍ is the current flowing through the battery device (2), nbr_cell is the number of cells (4) contained in the entire battery device (2); The management method (100) of claim 6.

8. said step (E08) of determining at least one limiting parameter and / or at least one parameter, moment t ｘ a substep (E095) of estimating the resistance of each cell connected to a busbar (5) in the battery device (2) comprising calculating the average resistance of the cells (4) of the battery device (2) not connected to a busbar (5) as a function of the voltage measured for these cells (4) and assigning such average value to each cell connected to the busbar (5); The minimum voltage value (V ｍｉｎ ) is the minimum discharge voltage threshold (S ｄ＿ｍｉｎ ) that can be allocated to the battery device (2). ｄｅ a substep (E096) of determining the discharge power (P ｄｅ a substep (E096) in which the resistances of the various cells (4) and the measured temperatures of each module are determined as a function of the resistances of the various cells (4) and the measured temperatures of each module; Including, The management method (100) of claim 6.

9. said step (E08) of determining at least one limiting parameter and / or at least one parameter, a substep (E097) of estimating the state of charge (SOC) of the various cells (4) of the battery device (2), the state of charge of the cell (4b) not connected to the busbar (5) is defined as a function of the measured voltage value and the current specific to the cell (4b); The state of charge of the cells (4a) connected to the busbar (5) is defined as a function of the current specific to the cells (4a) as follows: where: SOC ｔ is the state of charge of the cells connected to the busbar (5) at the instant t, I ｍ is the current flowing through the battery device, C is the capacitance of the cells connected to the busbar (5), Δt is the sampling time, The management method (100) according to any one of claims 1 to 4.

10. 1. A system (6) for managing an electric battery device (2) comprising a plurality of modules (3), each comprising a plurality of cells (4), wherein each module is electrically connected directly to at least one other module of the plurality of modules to form a module pair, the connection being made by busbars (5) connected at the cells of each module of the pair, the various modules (3) being electrically connected to each other, the system comprising hardware and / or software elements that implement the management method (100) according to any one of claims 1 to 4, the hardware elements comprising: at least one slave element (8) connected to each of the modules of the pair and capable of obtaining temperature and voltage measurements; a processing unit (7) capable of receiving measurements from the at least one slave element (8); a memory unit (9); and at least one current sensor (10).

11. 11. A hybrid or electric motor vehicle (1) comprising at least one electric battery device (2) comprising a plurality of modules (3) each comprising a plurality of cells (4), wherein each module is electrically connected to each of the other modules (3) of the plurality of modules (3) by a bus bar (5) in the vicinity of at least one cell, the vehicle (1) further being equipped with a management system (6) as described in claim 10.

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