CN110506359B

CN110506359B - Method for thermally regulating a fast-charging battery system of an electric motor vehicle

Info

Publication number: CN110506359B
Application number: CN201880024733.5A
Authority: CN
Inventors: 达米安·皮埃尔·圣弗洛; 米歇尔·索姆碧; 文森特·德·福莱格
Original assignee: PSA Automobiles SA
Current assignee: PSA Automobiles SA
Priority date: 2017-04-11
Filing date: 2018-03-09
Publication date: 2022-09-20
Anticipated expiration: 2038-03-09
Also published as: MA50282A; WO2018189438A1; EP3610533A1; FR3065118B1; CN110506359A; FR3065118A1

Abstract

The invention relates to a method for thermal regulation of a battery system (21) of a motor vehicle, comprising determining a target temperature of the battery system (21) which is required to be reached at the triggering moment of a planned charging of the battery system by means of a selected charging post (29). According to the invention, the method further comprises: the availability state of the charging post and the availability start schedule time of the charging post (29) for the vehicle are determined, and in the case of an unavailability state that prevents immediate triggering of the charging, active thermal regulation to a target temperature is triggered before the availability start schedule time. The invention is suitable for electric motor vehicles and hybrid motor vehicles with a charging interface.

Description

Method for thermally regulating a fast-charging battery system of an electric motor vehicle

Technical Field

The invention relates to a method for thermally regulating a battery system of a motor vehicle.

Background

The circulation of electric motor vehicles has led to the laying of charging stations on roads. Since these charging stations are present on highways, it is now possible to make long-distance trips. In order to reduce the charging time, it is foreseen that some charging stations will be equipped with so-called fast-charging piles or super-fast-charging piles, which provide charging power up to 350 kW.

It is known that during charging, the temperature of the battery system increases in accordance with the charging current. The battery system is temperature regulated in the operating range of about 20 ℃ to 55 ℃, while under load conditions, the temperature is typically actively regulated to maintain the temperature at about 45 ℃. During charging, when the temperature reaches the temperature protection limit, thermal regulation may cause the charging power accepted by the battery system to decrease, even temporarily stopping the charging operation when the temperature approaches 60 ℃. This phenomenon is common in long range trips, during which the initial charging temperature is kept near the protection limit. Fig. 1 schematically shows a journey of a motor vehicle during which a method known from the prior art is carried out for thermally regulating a battery system. The first graph shows the change in battery system temperature over time on the y-axis. In the lower part, the second graph shows on the y-axis the travel distance formed between the position P0, the position Px where the charging station is located, and the destination position Py. The running required electric power Pro is shown by colored regions located between the time t0 and the time t1 and between the time t3 and the time t 4. At time t1, the vehicle has arrived at the charging post. The charging power Pre implemented is shown by the colored region between the time t1 and the time t 2. It was observed that when charging was started, the temperature rapidly increased, which caused the interruption of the charging operation. This temperature protection increases the charging time and significantly increases the travel time. Furthermore, it is considered that the ultra-fast charging causes the heat loss to be so high that the temperature adjustment device cannot attenuate the thermal shock generated thereby during the charging.

The known document WO2014008122 describes a charging solution that proposes to provide an active thermal conditioning of the battery system during charging. Once the vehicle is connected to the charging post, the method proceeds to a first stage for determining a target temperature to be reached before triggering a charging operation. However, since the charging operation is triggered only when the thermal regulation has reached the target temperature, the charging operation is prolonged.

Disclosure of Invention

Therefore, it is necessary to reduce the operation time during charging by a so-called rapid charging pile or an ultra-rapid charging pile. In particular, it is desirable to propose a motor vehicle which can attenuate the thermal shock caused by the so-called ultra-fast charging piles (power greater than 50kW) and which can receive a plurality of charging operations in a long distance route without the occurrence of current limitation on the fast charging piles.

More precisely, the invention relates to a thermal regulation method for a motor vehicle battery system, comprising the determination of a target temperature of the battery system, which is required to be reached at the triggering moment of the planned charging of the battery system by means of a selected charging post. According to the invention, the method further comprises: the method comprises the steps of determining an availability status of a charging post and an availability start schedule time of the charging post of the vehicle, and triggering active thermal regulation of the control to a target temperature before the availability start schedule time in the case of an unavailability status that prevents immediate triggering of the charging.

Advantageously, the availability status is determined at least from a planned route to the selected charging post, and the availability start planning time is an estimate of the time at which the vehicle arrived at the selected charging post.

In a variant, the availability start scheduled time is a scheduled time at which the selected charging post supplies a charging current having a value that is the maximum current value accepted by the charging interface of the vehicle, if the scheduled supply time is later than the estimated value of the time at which the vehicle arrives at the selected charging post.

The regulation method can be performed according to two active thermal regulation modes. The method further includes determining first and second deadlines, the first deadline being an estimate of a remaining deadline before reaching the charge availability start schedule time, and the second deadline being an estimate of a deadline for the first operating mode that is thermally conditioned to reach the target temperature, and if the first deadline is greater than the second deadline, controlling to trigger the first operating mode when the first deadline becomes equal to the second deadline.

According to a variant, the second period is calculated from the available maximum cooling/heating potential of the vehicle thermal conditioning device.

Furthermore, the method comprises a second operation mode of thermal regulation, wherein the temperature profile is configured to gradually reach the target temperature between the charging post selection time and the charging availability start schedule time, and the thermal regulation of the second operation mode is controlled by the temperature profile.

Preferably, the method further comprises determining an estimate of the temperature change of the battery system between the charging post selection time and the availability start plan time without active thermal regulation, and the method allows triggering active thermal regulation only if the estimated temperature at the availability start plan time differs from the target temperature.

Specifically, the target temperature is calculated from the scheduled charging deadline, the scheduled charging power, and the charging end maximum temperature threshold.

Furthermore, in order to keep the charging current at a maximum throughout the planned charging process, the end-of-charge maximum temperature threshold is equal to the threshold that triggers limiting the charging current of the battery system.

According to the present invention, there is provided a motor vehicle having a control device configured to perform a method according to any one of the above embodiments.

By means of the invention, the thermal pre-treatment of the battery system prevents the occurrence of current limitation. In effect, the thermal mass of the battery system attenuates thermal shock caused by high power charging operations. Therefore, the charging current received by the charging interface of the vehicle is always at the maximum value. Thus reducing the charging time. Furthermore, with the present invention, there is no need to overdimension the thermal conditioning device so that it can maintain an operating temperature compatible with high power charging.

Drawings

Other features and advantages of the invention will appear more clearly on reading the following detailed description, which includes embodiments of the invention given as non-limiting examples and illustrated by the accompanying drawings, in which:

fig. 1 has been described in the description of the background art to illustrate a known thermal conditioning method;

figure 2 shows a block diagram of the electric vehicle functions involved in implementing the thermal conditioning method according to the invention;

fig. 3 shows a sequence of diagrams describing the thermal conditioning method according to the invention;

figure 4 shows a first operating mode of the thermal conditioning method;

fig. 5 shows a second operating mode of the thermal conditioning method.

Detailed Description

The present invention relates to the charging operation of battery systems and finds a particularly advantageous application for vehicles compatible with so-called ultra-fast charging stations, which provide charging powers greater than 50 kW. The invention will be described with respect to an electric motor vehicle system. Fig. 2 schematically shows a part of the functions of an electric vehicle 20 involved in the implementation of the method. However, the invention is also applicable to a hybrid vehicle having a charging interface. The vehicle includes functional devices 21 to 26, which will be described later, in which there is a control device 22 (also referred to as a manager) that is responsible for controlling the functional devices of the vehicle.

Generally, an electric motor vehicle includes an electric traction module 26 having a wheel set and an electric machine 27. A traction module having a single electric machine on an axle is shown herein, however, the present invention is also applicable to electric traction modules that include two or more electric machines and that are mounted according to other configurations known to those skilled in the art. Electric traction module 26 consumes power provided by power battery system 21 when electric traction module 26 is manipulated to provide torque to the wheels, and electric traction module 26 generates power when electric traction module 26 is controlled to charge battery system 21.

The power battery system 21 primarily supplies power to the traction module 26. A battery system is generally constituted by a plurality of battery cells and includes a control device whose function is to control a charge cycle and a discharge cycle during running of a vehicle. In addition, the battery system includes a temperature control device that can be operated according to a passive regulation mode to prevent the battery cells from exceeding a critical operating limit, such as a minimum temperature threshold of about 15 ℃ and a maximum temperature threshold of about 60 ℃. For this purpose, the temperature control device can prescribe a current limit to reach 0 ampere when the temperature of the battery system reaches 60 ℃. The battery system 21 comprises measuring means for measuring its activity parameters and is able to provide information relating to its activity parameters, in particular the state of charge level, the instantaneous operating temperature, the voltage at the battery terminals, the charge/discharge current, the charge current accepted as a function of the state of charge level and the instantaneous temperature, the internal resistance, the health parameters, the capacity, for operating the battery system 21 by means of the control means 22 of the vehicle.

In addition, the temperature control device of the battery system 21 is also operated according to the active heat regulation mode by cooperating with the thermodynamic cycle loop type heat regulation device 23. Generally, the thermal conditioning device 23 consists of a hydraulic circuit comprising at least a compressor, a condenser, an expander and an evaporator, and in which a heat-carrying fluid circulates. The circuit cooperates with the battery system 21 through a heat exchanger to cool or heat the battery system.

Typically, the hydraulic circuit of the heat-carrying fluid of the thermal conditioning device 23 is arranged to release heat and to provide thermal energy to the thermal mass of the battery system 21 through a heat exchanger. If the thermal conditioning device 23 is used for cooling and heating other equipment, for example the condenser of a cabin air conditioning circuit, the branch circuit of the thermal conditioning device 23 is particularly dedicated to the thermal conditioning of the battery system 21 and therefore comprises a heat exchanger of the plate or tube type, which is in contact with the components of the thermal mass forming the battery system 21. It should be noted that the branch circuit of the thermal conditioning device 23 comprises means for controlling the circulation of the heat carrying fluid (for example valves and temperature sensors), which are operated by the control device 22. The control device 22 operates the control member by means of the temperature set point and the thermal conditioning activation signal.

Furthermore, if the thermal conditioning device 23 is used to cool the cab, the cooling/heating potential of the thermal conditioning device 23 is distributed between the needs of the battery system and the needs of the cab. Thus, the distribution of the cooling potential is set. The thermal conditioning means 23 provide status information on the cooling/heating potential to the control means 22 to control the circulation of the heat-carrying fluid.

In addition, the electric vehicle 20 comprises a navigation device 25, which navigation device 25 is adapted to the function of road navigation by means of positioning devices of the vehicle (by means of, for example, satellite technology), road maps, route planning programs, road traffic information, and road services. To perform the thermal conditioning method, the navigation device 25 provides travel distance, remaining travel time to reach the selected charging post, and road traffic information. This is by no means a complete list and other navigation data may be used to perform the adjustment method. In the following description, the use of the navigation data by the thermal adjustment method will be described.

Furthermore, the navigation device 25 comprises a service module for managing charging at charging stations listed in the telematics system 28. More specifically, the charging service module has a charging pile location map and an information database providing attributes of each charging pile. In particular, the charging service module can indicate charging power available to the charging post, a charging service availability status, and a possible charging trigger time. In addition, the charging service module provides a function of reserving the charging pile in advance so as to ensure the availability of the charging pile. It should be noted that the charging service module communicates with the telematics system 28 to obtain information about the charging station (charging power, availability status, possible charging trigger time, wait time, geographic location, charging fee, etc. … …) in real time. For this purpose, the navigation device 25 of the vehicle communicates with the information system 28 via a radio frequency communication device (e.g., a cellular telephone network).

It should be added that the navigation device 25 is an on-board module of the vehicle. It is also possible that it performs all or part of the functions of the navigation device 25 by means of a portable device of the driver, for example a mobile telephone device equipped with a specific application for managing the charging of the vehicle. For this purpose, there is a short-range communication means (wired or radio frequency) between the driver's portable device and the navigation means 25 of the vehicle.

Furthermore, the vehicle 20 comprises a charging interface 24 intended to cooperate with a charging post 29 connected to the electric grid. The charging interface 24 is connected to the charging post 29 by cable or wireless charging technology. The charging interface 24 is compatible with a range of high-power charging powers and in particular with so-called rapid charging with an electric power of more than 50kW and up to 350 kW. During a so-called ultra-fast charge of 350kW, the average loss of thermal energy from the battery system is estimated to be around fifty kW. If the initial charging temperature is already around forty degrees, the resulting increase in battery system temperature can quickly trigger the current limiting measure.

Finally, the control device 22 comprises an integrated circuit computer for executing driving and navigation programs required for the operation of the vehicle. The management unit is responsible for controlling and configuring the devices in the drive train of the vehicle 20, in particular the battery system 21, the thermal regulating device 23, the traction module 26, the charging interface 24 and the navigation device 25.

The control device 22 is capable of executing the thermal conditioning method of the battery system according to the present invention. All steps of the regulating method are performed by the control device 22 according to a centralized function allocation. Some of these steps are de-allocated in the device according to a decentralized allocation pattern. The thermal control method is carried out when the vehicle is in a driving state and is driven to the charging station until the triggering time of the charging. It is advantageous to thermally pre-treat the battery system to prevent current limiting during charging. The thermal shock is therefore such that it is not limited by the action of the adjustment means 23. The thermal mass of the battery system 21, which has been previously reduced in temperature, attenuates this thermal shock by the present invention. Fig. 3 shows a graphical sequence for carrying out the thermal conditioning method, and fig. 4 and 5 show the temperature change of the battery system 21 during the execution of the thermal conditioning method.

In step 300, the vehicle is traveling and is shown at time ta in FIG. 4. At this stage, the driver selects the charging post 29 according to the availability status of the charging posts present near his planned route, which is shown in the lower part of fig. 4. The navigation device 25 includes a function of compiling planned route information and a charging service provided by the information system 28. In order to reduce the charging time, the driver will preferably select a rapid charging post that can deliver a charging current equal to the maximum charging current accepted by the charging interface 24 of the vehicle. Through the navigation interface, the driver selects the charging post 29 at a time ta at which to begin planning the route at a location P1, which location P1 corresponds to a time tc on the planned route. The driver has planned to move according to the planned route in the navigation device 25. The planned route includes a first road segment TRA between the position P0 at time ta and the charging pile position P1 to be reached at the estimated time tc, and a second road segment TRB between the position P1 and the position P2.

In step 301, the manager determines attributes of the charging post 29, in particular its geographical position in the planned route TRA, the available charging power, and a status indicating whether the charging post is free, occupied, or reserved at the estimated arrival time tc of the charging post. In particular, the method determines an availability status of the charging post and a charging post availability start schedule time tc. The availability status is determined at least from the planned route TRA to the selected charging post. Therefore, the availability start schedule time tc is calculated from the estimated value of the schedule term Dpar for the vehicle to reach the selected charging pile. As can be seen in fig. 4 and 5, the availability start schedule time tc of the charging pile is an estimate of the time at which the vehicle arrives at the charging pile 29.

However, other scenarios are possible. If the navigation device 25 detects that there is a planned waiting time at the arrival of the vehicle to allow connection to the charging post, this waiting time is added to the arrival time tc to calculate the availability start time.

If the charging pile is capable of supplying the quick charging power equal to or greater than 50kW, the availability start schedule time tc is further calculated from the quick charging power availability waiting period. Thus, the method comprises the detection step: the charging power available to the charging post is detected with respect to a predetermined threshold value, which is specified to be 50kW or more, for example. The availability start time is a scheduled time for the selected charging post 29 to supply a charging current having a value that is the value of the maximum current received by the vehicle charging interface 24 if the scheduled supply time is later than the estimated value of the time at which the vehicle arrives at the selected charging post 29. A waiting time may be set for a charging station having a plurality of charging piles, and the charging pile power of such a charging station may be temporarily reduced to supply all the charging piles with power.

Then, in step 302, the method detects whether the charging availability start schedule time tc is equal to a time ta corresponding to the time at which the charging pile 29 is selected. If the result is positive, the method then proceeds to step 313. This stage will be described in the following description.

This is not the case in this driving situation, since the vehicle still has to travel the section TRA. This is therefore the unavailability state of charging post 29 which prevents charging from being triggered immediately, and then the process proceeds to step 303.

In step 303, the method has identified a travel time Dpar before the time tc of arrival at the charging post. This is an opportunity to allow thermal pre-treatment of the battery system 21 before triggering a charging operation at time tc. The method determines a target temperature Tcib for the battery system that needs to be reached to trigger charging provided by the selected charging pile 29. The target temperature is a value or range of values. For example, it may be estimated that the initial target charge temperature for accepting rapid charging is between the battery system minimum operating limit STmin (e.g., 15 ℃) and about 25 ℃. The target temperature may be selected as the maximum limit of the value range to avoid excessive power consumption of the thermal conditioning device.

For this reason, in the first modification, the target temperature Tcib is a predetermined value configured in the manager, for example, the value is between 15 ℃ and 25 ℃. The predetermined value Tcib is calibrated according to a reference charging pattern determined in the vehicle design (with a defined charging depth, which is for example 60% of the total capacity of the battery system) which ensures that the current limit is not triggered during rapid charging. More specifically, the target temperature Tcib is configured such that the thermal mass of the battery system 21 prevents the temperature from increasing beyond the maximum threshold value STmax.

In the second modification, the control device 22 calculates the target temperature Tcib from the instantaneous state of the battery system 21. This mode is particularly advantageous for charging at lower charge depths, for example less than 30% of the battery system capacity. More specifically, the target temperature Tcib is calculated from the planned charging period, the available charging power (50kw or more), and a charging end maximum temperature threshold STmax, which is specified as 55 ℃ in the example of fig. 4, and which corresponds to the maximum temperature threshold of the trigger current limit. The current limit is lower than the instantaneous charging current and is configured to reduce the charging current so as to reduce the temperature rise of the battery until the charging current is zero.

More specifically, the planned charging deadline is calculated by using the planned route TRA as an input parameter. This discharge estimation mode calculates an estimate of the state of charge level of the battery system 21 at the time tc of arrival at the charging pile 29, and thus determines the planned charging depth. The control device then calculates an estimate of the charging period based on the planned charging depth, the maximum charging current accepted by the battery system 21, and the available charging power in the charging post 29. The charging deadline corresponds to an uninterrupted charging activity controlled by a maximum accepted charging current. Based on the scheduled charging period and the maximum accepted charging current, the control device 22 calculates a temperature rise estimation value Vmt. Subsequently, control device 22 determines the value of target temperature Tcib by subtracting temperature increase value Vmt from charge end maximum temperature threshold STmax. It should be noted that in the case of rapid charging, even under the action of the regulating device 23, the charging current reaches a value which prevents the temperature of the battery system from dropping or remaining.

Further, the estimated value of the state of charge level of the battery system 21 is calculated from the state of charge at the time ta, the planned route TRA, and the estimated value of the required electric power Pro for passing through the section TRA. The control device 22 has a power consumption model according to the planned route, which is used to estimate a change in state of charge of the planned route.

In addition, in step 304, the method includes determining an estimate of the temperature change Prf of the battery system 21 between the charging post selection time ta and the availability start plan time tc without active temperature thermal regulation, and the method further authorizes triggering of active temperature regulation only if the final estimated temperature Tfin at the availability start plan time tc is different from the target temperature Tcib. In fact, if the estimated value of the temperature variation Prf over the section TRA brings the battery system to a final temperature Tfin compatible with the target temperature Tcib or target temperature range, no active thermal regulation is required. This therefore avoids unnecessary power consumption. The estimate of the temperature change Prf provides the final estimate Tfin without active thermal regulation. The temperature variation Prf is calculated from the driving climate conditions and the required electric power Pro over the section TRA.

As shown in fig. 4, after step 304, a series of detections relating to the temperature of the battery system 21 are performed. In step 305, the method detects whether the final temperature estimate Tfin is equal to the target temperature Tcib. If the result is positive, the process returns to the initial step 301. Otherwise, the method then detects in step 306 whether the instantaneous temperature Tbat of the battery system 21 is equal to the target temperature Tcib. If the result is positive, the process returns to the initial step 301. Otherwise, the process proceeds to the next step 307.

In step 307, the method determines the period Dreg of the thermal regulation operation to reach the target temperature Tcib based on the instantaneous temperature of the battery system 21, which corresponds to the estimated value of the temperature variation Prf in the road section TRA. The term Dreg is estimated by a temperature regulation model and a thermally regulated operation mode recorded in the vehicle control device 22. The temperature regulation period Dreg is calculated by the thermal regulation device 23 from the thermal energy potential (cooling or heating potential). The thermal regulation mode of operation is the regulation mode permitted by the regulation device 23 for the maximum level of cooling or heating potential of the battery system 21.

It is well known that the thermal energy potential for the battery system 21 depends on the allocation between the cab and the battery system 21. In a variant, the allocation strategy of the control device 22 may set an allocation weighting between the thermal demand of the cab and the thermal demand of the battery system in the case of a total demand greater than the maximum capacity of the regulating device 23.

In step 308, the method checks whether the period Dreg is equal to or greater than the remaining trip period Dpar. In case of a positive result, the thermal conditioning operation is triggered starting from time ta and the method proceeds to step 309. This situation is not the one shown in fig. 4.

If the period Dreg is less than the remaining stroke period Dpar, active thermal regulation is triggered according to one of two thermal regulation modes described below and shown by the double solid line type temperature lines M1 and M2 in fig. 4. The selection between the first mode and the second mode depends on configuration parameters of the control device 22.

In step 310, in the first thermal regulation mode M1, the triggering of the thermal regulation operation is postponed to a future time tb1 for which tb1 the regulation period Dreg should be equal to the remaining stroke period Dpar. Tb1 corresponds to the time of the planned route TRA between time ta and time tc. This first regulation mode allows to save the electrical energy of the battery system, since the temperature of the battery system will reach the target temperature Tcib exactly at the moment tc of the start of the availability of charging, which is the moment at which the vehicle arrives at the charging post or after the vehicle arrives at the charging post in the event of a predicted waiting time. In addition, the first thermal conditioning mode M1 uses the maximum cooling/heating potential of the conditioning device 23 available to the battery system. It should be noted that the control of the adjustment period Dreg and the remaining stroke period Dpar takes place on the route TRA and the control device 22 activates the triggering of the active thermal regulation at the time tbl, which is then controlled to the target temperature Tcib. The thermal adjustment device 23 receives the target temperature Tcib calculated in step 303 as a thermal adjustment set value.

In step 311, in the second thermal regulation mode M2, the thermal regulation operation is triggered from the time ta (charging pile selection time). For the operation of this second regulation mode M2, the temperature profile is configured to gradually reach the target temperature Tcib from the charging-pile selection time ta to the planned time tc at which the charging availability starts, and the thermal regulation is controlled according to the temperature profile M2. It should be noted that the temperature change has a lower slope because the instantaneously applied cooling is lower than that of the first mode M1. This mode is characterized in particular by maintaining a constant cabin comfort. In contrast to the first mode, the control device 22 activates the triggering of the thermal regulation at the time ta and changes the ramp temperature profile to the thermal regulation setpoint.

Then, when the temperature of the battery system 21 reaches the target temperature Tcib, the method proceeds to step 312. This phase corresponds to the time tc when the charging post 29 is reached. The battery system 21 is preconditioned at a temperature condition compatible with an ultra-fast charging operation with a charging power Pre greater than 50 kW. At this step 312, the vehicle is connected to the selected charging post 29 and the charging is triggered at a charging power Pre greater than 50 kW.

As seen in fig. 4, after time tc, since the temperature rise is completely attenuated by the thermal mass of the battery system 21, the scheduled charging operation is performed without limiting the charging current. If the thermal substance can completely suppress the temperature rise, the charging operation is performed without the thermal regulation action, or the charging operation is performed under the thermal regulation action. The charging power Pre is kept constant throughout the operation. In addition, since the thermal pretreatment is performed during the vehicle travels to the charging post 29 and during the waiting time at the charging post as needed, the charging time can be shortened.

As shown in fig. 4, at time td, the temperature of the battery system reaches the maximum temperature threshold value STmax. If the driver wishes to continue driving immediately, he should wait for the temperature to drop until the time te, and continue the journey after the time te to complete the section TRB. This temperature drop is effected passively or it is conceivable for the control device 22 to perform an active thermal regulation at the end of the charging operation.

To avoid this waiting time, in an alternative embodiment of the method, the target temperature Tcib is calculated so that the charge end temperature reaches a value that allows the optimum running electric power Pro after the charge end time td. This is shown in fig. 5. The reference numerals of fig. 5 remain the same as fig. 4, and the executed thermal regulation mode is the first regulation mode M1 already described in fig. 4. In this case, the method is performed similarly to the case of fig. 4, with the difference that at the time tb2 an active thermal regulation controlled by the temperature setpoint Tcib is triggered.

Unlike fig. 4, the target temperature Tcib is configured to be a value of the minimum temperature threshold STmin, for example, 15 ℃. It is appreciated that the minimum temperature threshold corresponds to a temperature limit below which operation of the battery system is not optimal (e.g., performance degradation, accelerated aging). The threshold may correspond to a threshold at which the thermal regulating device provides heat to the battery system when the temperature of the battery system reaches the threshold. In this thermal regulation mode, after charging at the time td, the electric traction module can operate in an optimal manner without the risk of current limitation resulting from an excessively high end-of-charge temperature. The driver can start the second road segment from time td. The charging operation is reduced.

The flow of the method in step 313 is now described. In step 302, the method has detected that the charging availability start time tc is equal to time ta. In this case, unlike the case shown in fig. 4 and 5, the vehicle is already connected to the charging post 29 and the charging power can be triggered from the time ta. Similar to step 303, the method calculates a target temperature Tcib. If, at step 314, the method detects that the instantaneous temperature Tbat is different from the target temperature Tcib or the charge compatible temperature range, control device 22 triggers a thermal regulation operation at step 315. The target temperature set value calculated in step 313 is transmitted to the thermal conditioning device 23. Otherwise, the method proceeds to step 312 without thermal conditioning. At this step 312, charging is triggered at a charging power Pre greater than 50 kW.

The situation in which the vehicle has not yet reached the selected charging post has been described in fig. 3 to 5. In another driving situation, the vehicle is already connected to the charging post, and the charging post selection is made during the connection of the vehicle to the charging post. However, due to the inherent nature of the charging post, the charging post may supply a charging current that is less than the maximum current accepted by the charging interface 24 when connected, or even zero. The control device determines the charging availability start schedule time by directly viewing availability status data at the charging post via the charging interface. Thus, the availability start schedule time is the time that may trigger charging by the selected charging post that allows the maximum current received by the vehicle charging interface 24 to be supplied. Thus, the method utilizes the waiting time for the thermal pretreatment of the battery system.

Claims

1. A method for thermal regulation of a motor vehicle battery system (21), the method comprising determining (303) a target temperature (Tcib) of the battery system that needs to be reached at a triggering moment of planned charging of the battery system by a selected charging post (29), characterized in that the method further comprises: -determining (301) an availability status of the charging post (29) and an availability start schedule time (tc) of the charging post (29) for the vehicle, and-in case of an unavailability status preventing immediate triggering of charging, -triggering (309; 310; 311) an active thermal regulation controlled to the target temperature (Tcib) before the availability start schedule time (tc).

2. Method according to claim 1, characterized in that the availability status is determined at least according to a planned route (TRA) to the selected charging post (29) and that the availability start planning time (tc) is an estimate of the time at which the vehicle arrives at the selected charging post (29).

3. Method according to claim 2, characterized in that the availability start schedule time (tc) is a schedule time at which the selected charging post (29) supplies a charging current having a value that is the value of the maximum current accepted by the charging interface (24) of the vehicle, if the scheduled supply time is later than the estimated time at which the vehicle arrives at the selected charging post (29).

4. The method according to any of claims 1 to 3, further comprising a determination (307) of a first and a second time limit (Dpar, Dreg), the first time limit (Dpar) being an estimated value of a remaining time limit before reaching the charging availability start schedule time (tc) and the second time limit (Dreg) being an estimated value of a first operation mode (M1) thermally adjusted to reach the target temperature (Tcib), and controlling to trigger the first operation mode when the first time limit becomes equal to the second time limit if the first time limit (Dpar) is greater than the second time limit (Dreg).

5. Method according to claim 4, characterized in that the second period of time (Dreg) is calculated from the available maximum cooling/heating potential of the vehicle's thermal conditioning device (23).

6. The method according to claim 4, characterized in that it further comprises a second operation mode (M2) of thermal regulation in which a temperature profile is configured to gradually reach said target temperature (Tcib) between said charging post selection moment (ta) and said charging availability start plan moment (tc), and in which the thermal regulation of said second operation mode is controlled by said temperature profile.

7. The method according to claim 6, further comprising determining (304) an estimated value of a temperature variation (Prf) of the battery system between the charging post selection time (ta) and the availability start plan time (tc) without the active thermal conditioning effect, and allowing triggering the active thermal conditioning only if the estimated temperature (Tfin) of the availability start plan time (tc) differs from the target temperature (Tcib).

8. Method according to claim 7, characterized in that the target temperature (Tcib) is calculated from a planned charging deadline, a planned charging power and a charging end maximum temperature threshold (STmax).

9. Method according to claim 8, characterized in that said end-of-charge maximum temperature threshold (STmax) is equal to a threshold triggering a limitation of the charging current of said battery system.

10. A motor vehicle comprising a control device (22), characterized in that the control device (22) is configured to perform the method according to any one of the preceding claims.