Battery management method
The battery management process and system address the issue of energy overconsumption and mission failure by optimizing preheating and preloading based on battery state and temperature conditions, ensuring consistent functionality and reduced energy use.
Patent Information
- Application Number
- FR2022012947
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-12-08
- Publication Date
- 2025-05-02
- Estimated Expiration
- 2042-12-08
AI Technical Summary
Existing battery management systems in vehicles with rechargeable batteries, such as electric buses and trucks, often require preheating or preloading to maintain battery functionality, leading to energy overconsumption and potential mission failure if not activated correctly, which can impact the vehicle's ability to start or perform auxiliary tasks.
A battery management process and system that determines the battery's charge state and temperature conditions to ensure it can fulfill a mission profile, including stages for evaluating capacity, determining corrective actions, and executing auxiliary sequences like preheating or preloading to optimize energy use.
Ensures the battery can consistently perform its mission while minimizing energy consumption by adaptively managing preheating and preloading, ensuring the battery is functional when needed and optimizing energy usage.
Smart Images
Figure 00000021_0000 
Figure 00000022_0000 
Figure 00000023_0000
Abstract
Description
Title of the invention: Method for managing a battery Technical field of the invention
[0001] The present invention relates to a method and system for managing a battery. State of the art
[0002] As is known, some vehicles, which use rechargeable batteries, for example of the Lithium-Ion type, have a system for preheating their batteries and even for charging them, before putting them into operation, in order to avoid any risk of the vehicle not starting. This is the case, for example, of electric buses, certain airplanes or certain electric or thermal trucks.
[0003] The system is used during parking phases to maintain the batteries at a sufficient state of charge and / or at a sufficient temperature, these two parameters influencing the ability of the battery to start, after a stop.
[0004] For example, high electrical power is required when starting an electric bus. For some trucks that make long journeys, batteries are often used for auxiliary tasks (lighting, heating, cooking, etc.).
[0005] If the system is not present or not activated, the mission (starting or other) may not be assured. And when this type of system must be activated, this inevitably results in excess consumption of fuel and energy.
[0006] The aim of the invention is to propose a solution to ensure that the electric battery can always fulfill its mission, by limiting if possible the use of preheating and / or precharging, with the aim of consuming a minimum of energy. Presentation of the invention
[0007] This aim is achieved by a method for managing a battery, implemented using a management system, said battery being intended to follow a mission profile in power or current starting from a determined instant t1, subsequent to an initial instant t0, said method comprising steps of: - Determination of a theoretical value of the state of charge of the battery at time tl, from the initial state of charge of the battery measured at time tO and theoretical data of battery consumption between times tO and tl - Evaluation of the capacity of the battery to fulfill the mission profile in state of charge at said instant tl, from the theoretical value of the state of charge of the battery at instant tl, and from a minimum state of charge value from which the mission profile can be ensured, - Determination of a theoretical functional state of the battery at time tl, said battery being able to be in a functional state when it is capable of fulfilling the mission profile or in a non-functional state when it is not capable of fulfilling the mission profile at time tl, - Execution of an auxiliary sequence so that the battery is able to perform the mission profile when the battery is determined to be in a non-functional state at time tl.
[0008] According to a first variant embodiment, the auxiliary sequence consists of: - Evaluating the need for corrective action to be applied to the battery for the execution of the mission profile, - Determine the corrective action to be applied if it was considered necessary.
[0009] According to another particularity, evaluating the need to apply a corrective action to be taken to the battery consists of comparing a theoretical value of the state of charge of the battery with a real value measured at a given time t0' prior to said time t1 and subsequent to t0.
[0010] According to another feature, the method comprises steps of: - Determination of theoretical values of the ambient temperature between times tO and tl, - Determination of theoretical values of the battery temperature at time tl, from the theoretical values of the ambient temperature, - Determination of the minimum battery charge state required to complete the mission profile, based on the battery temperature.
[0011] According to another particularity, the method also comprises a step of evaluating the capacity of the battery to fulfill the temperature mission profile at said instant t1, from the theoretical value of the temperature of the battery at instant t1, and from a minimum temperature value from which the mission profile can be ensured.
[0012] According to another particularity, evaluating the need to apply a corrective action to be taken to the battery involves comparing a theoretical temperature value of the battery with an actual value measured at a given time t0' prior to said time t1 and subsequent to time t0.
[0013] According to another feature, the step of determining theoretical values of the ambient temperature between tO and tl is carried out by acquiring data on a remote server.
[0014] According to another feature, the method comprises a step of putting the management system on standby between time t0 and time t0'.
[0015] According to another feature, the corrective action consists of preheating the battery and / or in one battery charge.
[0016] According to another particularity, the method comprises a step of evaluating the application of a corrective action for charging the battery, taking into account a variation, as a function of the temperature, of the minimum state of charge of the battery necessary for carrying out the mission profile.
[0017] According to another variant embodiment, the method comprises: - A step of determining a theoretical curve of the state of charge of the battery over a time period subsequent to t0, from the initial state of charge of the battery measured at time t0 and the theoretical data of consumption of the battery over said time period subsequent to t0, - A step of determining a theoretical curve of the temperature of the battery over said time period after t0, from the initial temperature of the battery measured at time t0 and the theoretical values of the ambient temperature over said time period after t0, - A step of evaluating the capacity of the battery to fulfill the mission profile in state of charge over said time period, by comparing the theoretical state of charge curve with a minimum state of charge curve for which the battery is capable of fulfilling the mission profile, and / or - A step of evaluating the capacity of the battery to fulfill the temperature mission profile over said time period, by comparing the theoretical temperature curve of the battery with a minimum temperature curve for which the battery is capable of fulfilling the mission profile.
[0018] According to a particular feature, the method comprises a step of determining the minimum state of charge curve for which the battery is capable of fulfilling the mission profile from said theoretical temperature curve.
[0019] According to another feature, the auxiliary sequence consists of determining one or more instants, other than instant tl, at which the battery will be capable of fulfilling the mission profile.
[0020] The invention also relates to a system for managing a battery, said battery being intended to follow a mission profile in power or current starting from a determined instant t1, after an initial instant t0, said system comprising: - A module for determining a theoretical value of the state of charge of the battery at instant t1, from the initial state of charge of the battery measured at instant t0 and from theoretical data of consumption of the battery between instants t0 and t1 A module for evaluating the battery's capacity to fulfill the mission profile in the state of charge at said instant tl, based on the theoretical value of the state of charge of the battery at instant tl, and a state of charge value minimum from which the mission profile can be assured, - A module for determining a theoretical functional state of the battery at time tl, said battery being able to be in a functional state when it is capable of fulfilling the mission profile or in a non-functional state when it is not capable of fulfilling the mission profile at time tl, - A module for executing an auxiliary sequence so that the battery is able to carry out the mission profile when the battery is determined to be in a non-functional state at time tl.
[0021] According to a first variant embodiment, the auxiliary sequence consists of: - Assess the need for corrective action to be applied to the battery for the execution of the mission profile, - Determine the corrective action to be applied if it was considered necessary.
[0022] According to a particular feature, to evaluate the need to apply a corrective action to be taken to the battery, the system comprises a module for comparing a theoretical value of the state of charge of the battery with an actual value measured at a given time t0' prior to said time t1 and subsequent to t0.
[0023] According to another feature, the system comprises: - A module for determining the theoretical values of the ambient temperature between times tO and tl, - A module for determining the theoretical values of the battery temperature at time tl, from the theoretical values of the ambient temperature, - A module for determining the minimum battery charge state required to complete the mission profile, based on the battery temperature.
[0024] According to another particularity, the system comprises a module for evaluating the capacity of the battery to fulfill the temperature mission profile at said instant t1, from the theoretical value of the temperature of the battery at instant t1, and from a minimum temperature value from which the mission profile can be ensured.
[0025] According to another particularity, to evaluate the need to apply a corrective action to be taken to the battery, the system comprises a module for comparing a theoretical temperature value of the battery with an actual value measured at a given time t0' prior to said time t1 and subsequent to time t0.
[0026] According to another feature, the module for determining theoretical values of the ambient temperature between t0 and t1 comprises means for acquiring data on a remote server.
[0027] According to another feature, the system comprises a module for putting the management system on standby between time t0 and time t0'.
[0028] According to another feature, the corrective action consists of preheating the battery and / or charging the battery.
[0029] According to another feature, the system comprises a module for evaluating the application of a corrective action for charging the battery, taking into account a variation, as a function of the temperature, of the minimum state of charge of the battery necessary for carrying out the mission profile.
[0030] According to another feature, the system comprises: - A module for determining a theoretical curve of the state of charge of the battery over a time period subsequent to t0, from the initial state of charge of the battery measured at time t0 and the theoretical data of consumption of the battery over said time period subsequent to t0, - A module for determining a theoretical curve of the battery temperature over said time period after t0, from the initial temperature of the battery measured at time t0 and the theoretical values of the ambient temperature over said time period after t0, - A module for evaluating the capacity of the battery to fulfill the mission profile in state of charge over said time period, by comparing the theoretical state of charge curve with a minimum state of charge curve for which the battery is capable of fulfilling the mission profile, and / or - A module for evaluating the battery's capacity to fulfill the temperature mission profile over said time period, by comparing the theoretical temperature curve of the battery with a minimum temperature curve for which the battery is capable of fulfilling the mission profile.
[0031] According to another feature, the system comprises a module for determining the minimum state of charge curve for which the battery is capable of fulfilling the mission profile from said theoretical temperature curve.
[0032] According to another variant embodiment, the auxiliary sequence consists of determining one or more instants, other than instant t1, at which the battery will be capable of fulfilling the mission profile. Brief description of the figures
[0033] Other characteristics and advantages will appear in the detailed description which follows given with reference to the appended drawings in which: - Figures 1A and 1B illustrate the operating principle of the invention; - [Fig.2] shows a diagram illustrating the temperature variation of a battery as a function of ambient temperature over time; - [Fig.3] shows the effect of temperature on the battery operating state and illustrates the operating principle of the invention;
[0034] Detailed description of at least one embodiment
[0035] The invention applies to at least one electric battery, for example of the Lithium-Ion type. By battery, it is meant that it can comprise one or more cells, the cells being connected in series and / or parallel. The term "battery" also encompasses what is commonly called a "battery pack", composed of several batteries.
[0036] In the remainder of the description, the expression "configured to" or "configured for" means that the system considered has the hardware and / or software means to implement the function described.
[0037] The invention thus aims to optimize the management of a battery.
[0038] In a known manner, a management unit is responsible for monitoring the battery. This management unit comprises what is known as BMS (for "Battery Management System" - hereinafter referred to as BMS system), intended for monitoring and managing the battery, in particular its temperature, its state of charge, the current and the power it delivers. The BMS system is associated with sensors responsible for measuring the various quantities.
[0039] In the context of the invention, the management unit may also comprise a battery energy management system (EMS for "Energy Management System" - hereinafter referred to as the EMS system) responsible for determining the capacity of the battery to follow a particular mission profile, at a given time. For this, the EMS system implements the management method as described below, in connection with [Fig.lA] and [Fig.lB]. The system implements software and hardware modules adapted to the implementation of the management method.
[0040] When the electric vehicle is stopped, its BMS system is deactivated, the data normally acquired by the BMS system is therefore no longer available. The EMS system is therefore executed just before the BMS system is stopped, at time t0, so as to be able to generate the theoretical data necessary to maintain battery management, and to be able to best ensure a subsequent restart of the battery, to fulfill a given mission.
[0041] The different steps of the method according to the invention are referenced E1 to E13 and are illustrated by [Fig.lA] and [Fig.lB]. Some of these steps may be optional.
[0042] El: The EMS system relies on the following input data, acquired while the BMS system is still active at tO and before it is put into standby (the BMS is put into standby after tO): - The ambient temperature T_amb_t0 at time tO - it is for example measured by a sensor and sent to the BMS system; - The battery temperature T_batt_tO at time tO; - The state of charge SOC_tO of the battery at time tO - it is determined by the BMS system; - The instant tl at which the battery is required to fulfill the mission - it is entered for example by the user; - The PM mission profile that the battery will be required to execute - it is for example entered by the user or pre-stored in the BMS system, among several known classic mission profiles;
[0043] This data is for example acquired by the EMS system, just before the BMS system goes into standby state.
[0044] To fulfill this mission, the battery is requested to discharge according to a mission profile, also known. The mission profile PM may consist of a strong variation in the maximum current delivered by the battery at time t1 or a variation in the power delivered by the battery at time t1. Preferably, the mission entrusted is of a short and intensive nature, such as a one-off need for high power linked to starting the vehicle.
[0045] For the remainder of the description, we also define: - The PO period from t0 to tl; - The PI period after tl;
[0046] E2: The EMS system is configured to acquire ambient temperature data T_amb_th over the PO period, as well as optionally over the PI period, for a given location. For example, this temperature data can be obtained by the BMS system (before it goes into standby) or by the EMS system by connecting to MO weather servers. This gives a theoretical curve of variation of the ambient temperature.
[0047] E3: Starting from the input data, the EMS system is configured to execute an electrothermal model M_ET of the battery to determine: - Theoretical values of the temperature T_batt_th of the battery at time tl, and optionally over the period PO and over the period PI - these theoretical values are estimated from the ambient temperature T_amb_t0, the temperature T_batt_tO of the battery measured at tO, and the theoretical curve of variation of the ambient temperature determined in step E2 for the period PO and optionally for the period PI - [Fig.2] shows a curve of variation of the temperature of the battery T_batt_th as a function of the variation of the estimated ambient temperature T_amb_th; - Theoretical values of the state of charge SOC_th of the battery at time tl, and optionally over the PO period and the PI period - these values theoretical are estimated from the state of charge SOC_tO of the battery obtained at time tO and an estimate of the battery consumption over the PO period and optionally over the PI period, this estimate being carried out by knowing the PM mission profile that the battery will be required to follow. The time step simulation also makes it possible to take into account the effect of possible under-drawing on the battery (e.g. supply of auxiliaries) during the PO period; - Possibly, theoretical values of the battery energy state, if the total available energy is known;
[0048] In a known manner, an electrothermal model M_ET makes it possible to simulate different charge / discharge currents and powers at different temperatures, taking into account the dispersion of resistances and capacities. It is modular in relation to the electrical and geometric architecture of the battery.
[0049] As a non-limiting example, the electrical part of the model consists of a multi-cell model with a voltage source (OCV: open circuit voltage) and a resistance for each cell. Thus the voltage of each cell U is linked to the current I by the equation
[0050] U=OCV+RI
[0051] The thermal model is based on equations for heat generation and heat exchange with the surrounding air. It calculates the temperature per element according to its location in an area of the battery pack.
[0052] The heat exchange equation of the battery is expressed as follows:
[0053] (Qrev + Qirrev^-hx(T_batt_tl^- T_amb_fh^)
[0054] With: - m the mass of the battery; - Cp the heat capacity of the battery - known input data; - Qrev is the quantity of reversible heat generated by the battery; - Qirrev is the quantity of irreversible heat generated by the battery (linked to the Joule effect) = R*I2; - h the exchange coefficient with the exterior; - T_batt_th(t) the battery temperature at any time t estimated in step E3; we will mainly consider the temperature T_batt_th at time tl and optionally the temperatures T_batt_th over the period Pl; - T_amb_th(t) the ambient temperature at any time t estimated in step E2; we will mainly consider the temperature T_amb_th over the period PO (to deduce the temperature at time tl) and optionally the temperature T_amb_th over the period PI;
[0055] The electrothermal model M_ET makes it possible to obtain the currents, voltages, temperatures and the state of charge at the level of the different elements of the battery (cell, module, battery, battery pack, etc.)
[0056] An electrothermal model M_ET of a battery is for example described in the referenced publication "Management and electrothermal modeling of lithium-ion batteries - David Allart - 03 / 26 / 2018 - HAL Id: tel-01743791 -https: / / tel.archives-ouvertes.fr / tel-01743791.
[0057] E4: The EMS system has a model M_I / M_PW, expressing a maximum power profile and / or a maximum current profile that the battery will be able to deliver as a function of the temperature and the state of charge of the battery. The EMS system can thus deduce, for the PM mission profile to be fulfilled, at what temperature T_batt_PM and at what state of charge SOC_PM the battery must be in order to be able to fulfill this PM mission profile.
[0058] The choice of mapping the maximum power or the maximum current depends on the PM mission profile to be simulated. For some applications, notably those using lead batteries when starting a vehicle, the PM mission profile is generally in current, in relation to the "Cold Cranking Current" (maximum current supplied by the battery at -18 C). For other applications, the PM mission profile is in power.
[0059] Optionally, the results of step E4 can be simplified to consider only the state of charge SOC_PM in the rest of the decision process.
[0060] E5: Starting from the input data and the various elements obtained in the previous steps, the EMS system, via a suitable M_SOF module, is configured to determine the SOF function state of the battery at time tl, and optionally over the period PL
[0061] In other words, it is necessary to evaluate at time tl the capacity of the battery to fulfill the mission profile PM by taking into account its theoretical temperature variation curve T_batt_th and its theoretical state of charge variation curve SOC_th.
[0062] Two evaluation options are possible based on the T_batt_PM and SOC_PM data from step E4. - A simple approach is to limit oneself to the evaluation of the state of charge and verify that the state of charge SOC_th at time tl is greater than the minimum value SOC_ min necessary to carry out the mission at time tl. - Alternatively, a second, more precise approach based on the results obtained in step E4 requires: • Firstly, check that the temperature T_batt_th at time tl is greater than a minimum temperature value of the battery required to the exercise of the mission (referenced T_min) and which corresponds to the temperature T_batt_PM at time tl; • Then check that the state of charge SOC_th at time tl is greater than the minimum value (referenced S0C_min) necessary to carry out the mission and which corresponds to the state of charge SOC_ PM at time tl.
[0063] If the above condition(s) are met, then the battery is deemed functional to respond to the mission at time t1. Otherwise, the battery is deemed non-functional to respond to the mission at t1.
[0064] E6: Considering the second approach above, if the battery is determined at time tl in a functional state (SOF=1) both in temperature and in state of charge, the mission profile can be ensured at time tl.
[0065] E7: Considering the second approach above, if the battery is determined at time tl in a non-functional state (SOF=0) in temperature and / or in state of charge, the mission profile cannot be ensured at time tl.
[0066] And when the battery is indicated in a non-functional state at the time tl at which the mission profile is supposed to be executed, the EMS system is then configured to execute an auxiliary sequence S_Aux which can allow the battery to ensure the mission profile PM.
[0067] Two variant embodiments can be envisaged.
[0068] In a first variant, the auxiliary sequence S_Aux executed may consist of: - Determining the need for a corrective action to be applied to the battery to fulfill the mission profile at time tl; - Determine what corrective action to take if this action is necessary;
[0069] In a second variant, the auxiliary sequence S_Aux may consist of: - Determining one or more instants, other than instant tl, at which the battery will be capable of fulfilling the mission profile;
[0070] Steps E8 to E13 are described below for the first embodiment variant.
[0071] E8: The battery was determined to be in a non-functional state at time tl. The The EMS system then launches the auxiliary sequence S_Aux. For the first implementation variant, the auxiliary sequence S_Aux consists first of determining whether a corrective action AC to be applied to the battery is necessary so that it can fulfill the PM mission profile.
[0072] E9: To determine whether corrective action AC is necessary, the EMS system is configured to wake up the BMS system, so that it can again acquire real temperature and state of charge values, referenced T_batt_tO', SOC_tO'. The BMS system is woken up at a time t0', later than time tO and earlier than time tl, so as to be able to anticipate the execution of the mission profile by one or possible corrective actions.
[0073] The BMS system is awakened at time t0' (BMS_tO' in [Fig.lB]) only if a need for corrective action AC is predicted to meet the mission profile PM at time tl.
[0074] E10: After waking up the BMS system, the EMS system compares the theoretical values temperature T_batt_th_tO' and state of charge SOC_th_tO' determined (using the electrothermal model M_ET in step E3) at time t0' with the actual values T_batt_tO', SOC_tO' measured / estimated by the BMS system after its wake-up, at time t0'.
[0075] The EMS system then checks that the temperature predicted by the electrothermal model M_ET is indeed the one that the BMS system measures (for example to within 2°C) and that the state of charge of the battery that has been predicted corresponds to the state of charge estimated by the BMS (to within the precision of the estimation, for example 2%). If the measurements correspond to the predictions (branches Y in [Fig.lB]) or if the measurements give more restrictive values for future operation, the EMS system considers that the corrective action AC is necessary and then decides on the corrective action AC to be carried out.
[0076] El 1: The corrective action to be carried out may be a PH preheating of the battery and / or a PC precharge of the battery at t0', prior to time tl.
[0077] A PH preheating is necessary if, at time tl, the battery temperature is lower than the minimum temperature T_min necessary for the execution of the PM mission profile at this time tl.
[0078] A precharge is necessary if, at time tl, the state of charge of the battery is lower than the minimum state of charge S0C_min necessary for the execution of the mission profile PM at time tl.
[0079] The corrective action AC to be carried out will first advantageously be on the temperature (preheating action) because the action on the temperature often also makes it possible to correct the state of charge. Indeed, as indicated previously, the minimum state of charge from which the mission profile is achievable is higher at a lower temperature. It follows that if the temperature is increased (via preheating) so that it exceeds, at time tl, the minimum value T_min above which the mission profile is achievable, the minimum state of charge S0C_min is then reduced.
[0080] Then, the EMS system is configured to compare the state of charge of the battery (without precharging) with the updated minimum state of charge S0C_min (taking into account the new temperature T_min). If the updated state of charge of the battery remains lower than the new minimum state of charge S0C_min, the EMS system then also commands a precharging at t0'. Alternatively, it is also possible to evaluate the state of charge of the battery (possibly by measurement via the BMS) and the state of minimum charge SOC_min at the end of preheating, at a time after tO' but before tl, and to possibly carry out a precharge if it turns out that the measured state of charge remains lower than the minimum state of charge SOC_min. However, it will be necessary to maintain a sufficient duration before time tl for the implementation of the precharge.
[0081] The preheating PH is controlled by the EMS system so that the battery BATT reaches the minimum temperature T_min, for which the mission profile is achievable, at the latest at the time tl of start of execution of its mission profile PM.
[0082] Similarly, if a PC precharge is decided, the EMS system controls the charging of the battery so that its state of charge becomes equal to the minimum state of charge S0C_min at the latest at time tl.
[0083] E12: After waking up the BMS, if the theoretical temperature value T_batt_th_tO' or the theoretical state of charge value SOC_th_tO' is finally lower than the actual values acquired at time t0' by the BMS system, the EMS system then does not yet launch the corrective action AC (AC_tO'=NOK) and resets its temperature and state of charge values to the values acquired by the BMS system at t0'.
[0084] E13: The BMS system is put back into standby and the process described above, ranging from Steps E1 to E12 are restarted with the last values acquired by the BMS before it went back to sleep. The EMS system thus reassesses the need for corrective action with updated data that is closer to the actual values.
[0085] Steps E1 to E12 are repeated at a time t0", subsequent to t0' and always preceding time t1.
[0086] In summary, at t0, the EMS system evaluates the feasibility or otherwise of the PM mission profile at time t1. If this is not feasible, the EMS system identifies at which time t0' it will be necessary to launch a corrective action in preheating and / or precharging on the battery so that the PM mission profile can be executed by the battery.
[0087] The solution of the invention according to this first variant thus has numerous advantages. The system is thus self-adaptive with respect to the measurements of the BMS system. The BMS system is woken up at a time t0' only if a need for corrective action is identified, to respond to the mission profile at time t1. If the BMS system confirms the predicted values, the EMS system decides to take the corrective action, otherwise the temperatures and the state of charge of the EMS are reset to the measured values. And the BMS system goes back into standby mode until a new time to reassess the relevance of the corrective actions.
[0088] The second variant of implementation of the auxiliary sequence S_Aux consists of not implementing a corrective action, but of determining at which instant(s), other than instant tl, the mission profile PM can be executed by the battery.
[0089] From the known PM mission profile (step El), the EMS system can vary the instant tl in the application of steps E1 to E5 in order to determine one or more future instants for which the battery will be functional (SOF=1) for the execution of the mission profile and one or more future instants for which the battery will be non-functional (SOF=0) for the execution of the mission profile.
[0090] For this, the EMS system is configured to determine the functional state SOF of the battery in the state of charge and possibly in temperature (according to the two approaches described in step E5) and for a set of instants t1 subsequent to t0.
[0091] For the temperature, as an example and with reference to [Fig.3], the EMS system can be configured to compare the determined theoretical temperature variation curve with a minimum temperature curve (T_min), for which the mission profile can be executed.
[0092] As long as the theoretical temperature variation curve is above this minimum curve, the EMS system considers that the battery is in a functional state (SOF=1).
[0093] For the state of charge, the EMS system can proceed in an identical manner. As long as the theoretical state of charge variation curve is above a minimum state of charge variation curve (for which the mission profile can be executed), SOC_batt_PM, the EMS system considers that the battery is in a functional state (SOF=1).
[0094] The EMS system does this for both parameters and determines the functional or non-functional state of the battery over time.
[0095] This allows the user and / or system to plan when it would be possible to perform the mission profile without the need for corrective action.
[0096] The choice can therefore be made to anticipate the execution of the mission profile at a time when SOF=1 before entering a time range where SOF=0. The choice can also be made to delay the execution of the mission profile to carry it out at a time when SOF=1.
[0097] This second solution has the advantage of allowing for optimized mission planning with regard to heat and energy consumption linked to corrective actions, provided that there is flexibility in mission planning.
Claims
Claims
1. Method for managing a battery, implemented using a management system, said battery being intended to follow a mission profile (PM) in power or current starting from a determined instant tl, subsequent to an initial instant t0, characterized in that it comprises steps of: - Determination of a theoretical value of the state of charge (SOC_th) of the battery at time tl, from the initial state of charge of the battery measured at time tO and theoretical battery consumption data between times tO and tl, - Evaluation of the battery's capacity to fulfill the mission profile (MP) in state of charge at said instant tl, from the theoretical value of the state of charge (SOC_th) of the battery at instant tl, and from a minimum state of charge value (SOC_min) from which the mission profile can be ensured, - Determination of a theoretical state of function (SOF) of the battery at time tl, said battery being able to be in a functional state when it is capable of fulfilling the mission profile (PM) or in a non-functional state when it is not capable of fulfilling the mission profile (PM) at time tl, - Execution of an auxiliary sequence (S_Aux) so that the battery is able to perform the mission profile when the battery is determined to be in a non-functional state at time tl, - The auxiliary sequence (S_Aux) consisting of: • Assess the need for corrective action (CA) to be applied to the battery for the execution of the mission profile, • Determine the corrective action (CA) to be applied if it was considered necessary, and in that: - Evaluating the need for applying a corrective action (CA) to the battery consists of comparing a theoretical state of charge value (SOC_th_tO') of the battery with an actual value (SOC_tO') measured at a given time tO' prior to said instant tl and subsequent to tO.
2. Method according to claim 1, characterized in that it comprises steps of: - Determination of theoretical values of the ambient temperature (T_amb_th) between times t0 and tl, - Determination of theoretical values of the temperature (T_batt_th) of the battery at time tl, from the theoretical values of the ambient temperature, - Determination of the minimum state of charge (SOC_min) of the battery necessary for carrying out the mission profile, as a function of the temperature of the battery (T_batt_th).
3. Method according to claim 2, characterized in that it also comprises a step of evaluating the capacity of the battery to fulfill the mission profile (PM) in temperature at said instant tl, from the theoretical value of the temperature (T_batt_th) of the battery at instant tl, and from a minimum temperature value (T_min) from which the mission profile (PM) can be ensured.
4. Method according to claim 2 or 3, characterized in that evaluating the need to apply a corrective action (AC) to the battery involves comparing a theoretical temperature value (T_batt_th_tO') of the battery with an actual value (T_batt_tO') measured at a given time tO' prior to said time tl and subsequent to time tO.
5. Method according to one of claims 2 to 4, characterized in that the step of determining theoretical values of the ambient temperature (T_amb_th) between tO and tl is carried out by acquiring data on a remote server.
6. Method according to claim 2 or 4, characterized in that it comprises a step of putting the management system on standby between time t0 and time t0'.
7. Method according to one of claims 1 to 6, characterized in that the corrective action consists of preheating (PH) the battery and / or charging (PC) the battery.
8. Method according to claim 7, characterized in that it comprises a step of evaluating the application of a corrective load action (PC) of the battery, taking into account a variation, depending on the temperature, of the minimum state of charge of the battery necessary to achieve the mission profile.
9. Method according to claim 1, characterized in that it comprises: - A step of determining a theoretical curve of the state of charge (SOC_th) of the battery over a time period subsequent to t0, from the initial state of charge of the battery measured at time t0 and the theoretical consumption data of the battery over said time period subsequent to t0, - A step of determining a theoretical curve of the temperature (T_batt_th) of the battery over said time period subsequent to t0, from the initial temperature of the battery measured at time t0 and the theoretical values of the ambient temperature (T_amb_th) over said time period subsequent to t0, - A step of evaluating the capacity of the battery to fulfill the mission profile (PM) in state of charge over said time period,by comparing the theoretical state of charge curve with a minimum state of charge curve (S0C_min) for which the battery is capable of fulfilling the mission profile, and / or - A step of evaluating the capacity of the battery to fulfill the mission profile (PM) in temperature over said time period, by comparing the theoretical temperature curve (T_batt_th) of the battery with a minimum temperature curve (T_min) for which the battery is capable of fulfilling the mission profile.,
10. Method according to claim 9, characterized in that it comprises a step of determining the minimum state of charge curve (S0C_min) for which the battery is capable of fulfilling the mission profile from said theoretical temperature curve (T_batt_th).
11. Method according to claim 9 or 10, characterized in that the auxiliary sequence (S_Aux) consists of determining one or more instants, other than instant tl, at which the battery will be capable of fulfilling the mission profile.
12. Battery management system, said battery being intended to follow a mission profile (PM) in power or current starting from a determined instant tl, subsequent to an initial instant t0, said system being characterized in that it comprises: - A module for determining a theoretical value of the state of charge (SOC_th) of the battery at time tl, from the initial state of charge of the battery measured at time tO and theoretical battery consumption data between times tO and tl - A module for evaluating the capacity of the battery to fulfill the mission profile (PM) in state of charge at said instant tl, from the theoretical value of the state of charge (SOC_th) of the battery at instant tl, and from a minimum state of charge value (SOC_min) from which the mission profile can be ensured, - A module for determining a theoretical state of function (SOF) of the battery at time tl, said battery being able to be in a functional state when it is capable of fulfilling the mission profile (PM) or in a non-functional state when it is not capable of fulfilling the mission profile (PM) at time tl, - A module for executing an auxiliary sequence (S_Aux) so that the battery is able to carry out the mission profile when the battery is determined to be in a non-functional state at time tl, - The auxiliary sequence (S_Aux) consisting of: • Assess the need for corrective action (CA) to be applied to the battery for the execution of the mission profile, • Determine the corrective action (CA) to be applied if it was considered necessary, and in that: - To assess the need for applying a corrective action (CA) to the battery, the system includes a module for comparing a theoretical state of charge value (SOC_th_tO') of the battery with an actual value (SOC_tO') measured at a given time tO' prior to said instant tl and later than tO.
13. System according to claim 12, characterized in that it comprises: - A module for determining the theoretical values of the ambient temperature (T_amb_th) between times t0 and tl, - A module for determining the theoretical values of the temperature (T_batt_th) of the battery at time tl, from the theoretical values of the ambient temperature, - A module for determining the minimum state of charge (SOC_min) of the battery necessary for carrying out the mission profile, as a function of the temperature of the battery (T_batt_th).
14. System according to claim 13, characterized in that it comprises a module for evaluating the capacity of the battery to fulfill the mission profile (PM) in temperature at said instant tl, from the theoretical value of the temperature (T_batt_th) of the battery at instant tl, and from a minimum temperature value (T_min) from which the mission profile (PM) can be ensured.
15. System according to claim 13 or 14, characterized in that, to evaluate the need to apply a corrective action (AC) to be taken to the battery, the system comprises a module for comparing a theoretical temperature value (T_batt_th_tO') of the battery with an actual value (T_batt_tO') measured at a given time tO' prior to said time tl and subsequent to time tO.
16. System according to one of claims 13 to 15, characterized in that the module for determining theoretical values of the ambient temperature (T_amb_th) between tO and tl comprises means for acquiring data on a remote server.
17. System according to claim 12 or 15, characterized in that it comprises a module for putting the management system on standby between time t0 and time t0'.
18. System according to one of claims 11 to 17, characterized in that the corrective action consists of preheating (PH) the battery and / or charging (PC) the battery.
19. System according to claim 18, characterized in that it comprises a module for evaluating the application of a corrective action for charging (PC) the battery, taking into account a variation, depending on the temperature, of the minimum state of charge of the battery necessary to achieve the mission profile.
20. System according to claim 12, characterized in that it comprises: - A module for determining a theoretical curve of the state of charge (SOC_th) of the battery over a time period subsequent to t0, from the initial state of charge of the battery measured at time t0 and theoretical battery consumption data over said time period subsequent to t0, - A module for determining a theoretical curve of the temperature (T_batt_th) of the battery over said time period subsequent to t0, from the initial temperature of the battery measured at time t0 and theoretical values of the ambient temperature (T_amb_th) over said time period subsequent to t0, - A module for evaluating the capacity of the battery to fulfill the mission profile (PM) in state of charge over said time period,by comparing the theoretical state of charge curve with a minimum state of charge curve (S0C_min) for which the battery is capable of fulfilling the mission profile, and / or - A module for evaluating the capacity of the battery to fulfill the mission profile (PM) in temperature over said time period, by comparing the theoretical temperature curve (T_batt_th) of the battery with a minimum temperature curve (T_min) for which the battery is capable of fulfilling the mission profile.,
21. System according to claim 20, characterized in that it comprises a module for determining the minimum state of charge curve (S0C_min) for which the battery is capable of fulfilling the mission profile from said theoretical temperature curve (T_batt_th).
22. System according to claim 20 or 21, characterized in that the auxiliary sequence (S_Aux) consists of determining one or more instants, other than instant tl, at which the battery will be capable of complete the mission profile.