Method for generating a virtual prototype of a vehicle battery - Patents.com
Patent Information
- Application Number
- JP2024534752
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2021-12-17
- Filing Date
- 2022-12-16
- Publication Date
- 2025-12-26
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a method for generating a virtual prototype of a vehicle battery based on data from road measurements. [Background technology]
[0002] Vehicle batteries are used in electric or hybrid vehicles for the energy supply of the powertrain. From the prior art it is known to analyze the electrical behavior of vehicle batteries on the basis of physical data.
[0003] In order to analyze the electrical behavior of a vehicle battery and to analyze it as much as possible in all relevant operating situations, driving behaviors, and road and environmental conditions, very long test drives have to be mastered.
[0004] Moreover, such real test drives cannot yet be carried out during the battery development, but can only be carried out at a later stage in the development of the vehicle battery. From the prior art, it is basically known that virtual test drives can be carried out by means of a vehicle simulation tool, which, however, also requires a virtual prototype of the vehicle battery. Summary of the Invention [Problem to be solved by the invention]
[0005] It is an object of the present invention to provide a virtual prototype of a vehicle battery. In particular, it is an object of the present invention to automate the generation of a virtual prototype of a vehicle battery to as large an extent as possible. [Means for solving the problem]
[0006] This problem is solved by the teaching of the independent claims. Advantageous configurations are claimed in the dependent claims.
[0007] A first aspect of the present invention is a computer-implemented method for generating a virtual prototype of a vehicle battery based on data from road measurements, comprising: a work step of determining the values of the measured quantities of the measurement run, including the value of the terminal voltage; a work step of simulating a vehicle battery using a vehicle battery model, the vehicle battery model including battery parameters including an open circuit voltage, a load capacity at the time of discharge, an internal resistance at the time of discharge, an RC resistance at the time of discharge, and an RC capacity at the time of discharge, and at least a value of a terminal voltage is output as a target value; a work step of comparing at least one value of the terminal voltage calculated on the basis of road measurements with a value of the terminal voltage simulated by means of a vehicle battery model; - adjusting the vehicle battery model in order to match the simulated terminal voltage to the calculated terminal voltage based on road measurements by varying the values of the battery parameters; a work step of outputting values for battery parameters of the vehicle battery model; having The method involves repeating the steps of simulation, comparison and adjustment until an interruption condition is reached.
[0008] A second aspect of the invention relates to a system for generating a virtual prototype of a vehicle battery based on data from road measurements, comprising means for parameterization of a vehicle battery model of the virtual prototype with battery parameters, wherein the means are provided for parameterization and calculate values of battery parameters of the vehicle battery model in a simulation loop that optimizes the electrical parameters of the vehicle battery model based on measured values of the road measurements, in particular through a cascaded software-in-the-loop simulation, classified by specific conditions derived from the battery state and through a comparison of the simulated parameter values with parameter values calculated by the road measurements.
[0009] A third aspect of the invention relates to a system for generating a virtual prototype of a vehicle battery based on data from road measurements, the system comprising means for parameterization, the means for parameterization comprising: means for the calculation of at least one value for the terminal voltage based on the values of the measured quantities recorded during the measurement run; means for simulating a vehicle battery using a vehicle battery model, where the vehicle battery model comprises: o Load capacity; and o Internal resistance, especially during charging and discharging; o RC resistance, especially during charging and discharging, o RC capacitance, especially RC capacitance during charging and RC capacitance during discharging; Includes: A means for outputting at least a terminal voltage value as a target value; means for comparing at least one value of the terminal voltage calculated based on road measurements with a value of a simulated terminal voltage; means for adjusting a vehicle battery model to match a simulated terminal voltage to a calculated terminal voltage based on road measurements by varying values of battery parameters; an interface for outputting values for battery parameters of the vehicle battery model; Including, The system relates to a parameterization means for adjusting a vehicle battery model until an interruption condition is reached.
[0010] A fourth aspect of the invention relates to a method for analysing a vehicle battery, wherein the vehicle battery is simulated using a virtual prototype of the vehicle battery, the virtual prototype being generated using a method for generating a virtual prototype based on road measurements.
[0011] Further aspects of the invention relate to computer programs and storage media having instructions which, when carried out by a computer, cause the computer to carry out the methods according to the invention.
[0012] Road measurements within the meaning of the present invention are preferably field measurements, i.e. measurements which are carried out in real driving conditions of the vehicle.
[0013] A software-in-the-loop simulation in the sense of the present invention is preferably a simulation in which a part written in software is tested in a virtual model world.
[0014] Battery parameters in the sense of the present invention preferably characterize the characteristics of a vehicle battery. In particular, the battery parameters of a vehicle battery are described with the behavior of the vehicle battery during charge state fluctuations (charging or discharging), but also when no battery current is flowing. The battery parameters furthermore preferably result from the circuit of the battery components. The battery parameters preferably characterize the effect of an electric energy input from the vehicle battery and / or an electric energy output to the vehicle battery, which may occur, for example, during acceleration processes or regenerative braking, respectively. Furthermore, these dependencies may preferably be stored as function or cause and effect diagrams.
[0015] A terminal voltage in the sense of the present invention advantageously denotes the output voltage, in particular the averaged or filtered, onto the vehicle battery terminals.
[0016] The open circuit voltage in the sense of the present invention advantageously denotes the voltage, in particular averaged or filtered, to the vehicle battery terminals when no load current is flowing.
[0017] Load capacity in the sense of the present invention advantageously denotes the capacity of the vehicle battery in Ah or Wh, in particular the averaged or filtered capacity, whereby the load capacity when charging means the part of the total capacity of the vehicle battery that has not yet been charged and the load capacity when discharging means the part of the total capacity of the vehicle battery that has not yet been discharged.
[0018] The internal resistance in the sense of the present invention advantageously denotes the vehicle battery circuit resistance, which depends on the state of charge and on the battery temperature. The internal resistance when the vehicle battery is charged is fundamentally different from the internal resistance when the vehicle battery is discharged.
[0019] An RC resistance in the sense of the present invention advantageously denotes the resistance of the RC circuit of the vehicle battery, connected in series with its internal resistance.
[0020] RC capacitance in the sense of the present invention advantageously denotes the capacitance of the RC circuit of the vehicle battery, connected in series with its internal resistance.
[0021] The invention is based on an approach whereby the battery parameters of a vehicle battery can be determined by an iterative simulation method for a virtual prototype. In this way, the electrical charging and discharging behavior of the vehicle battery is simulated, without the need for further test drives with a test vehicle. In this way, a verifiable and high-quality vehicle battery model can be created with little effort and within a short period of time. The behavior of the terminal voltage as a function of the battery state can be simulated particularly accurately therein. The method according to the invention allows an automatic creation of a vehicle battery model on the basis of measurement data from road measurements.
[0022] Advantageously, in the method according to the first aspect, it is envisaged that the vehicle battery model further comprises the battery parameters of load capacity when charging, internal resistance when charging, RC resistance when charging and RC capacity when charging.
[0023] It is further advantageously envisaged that the vehicle battery model further includes the following battery parameters: load capacity when no current is flowing, internal resistance when no current is flowing, RC resistance when no current is flowing, and RC capacity when no current is flowing.
[0024] In particular, it is further assumed that the state of charge of the vehicle battery is included in the model parameters of the vehicle battery model.
[0025] Model parameters are parameters on which the vehicle battery model depends. In particular, battery parameters included in the vehicle battery model may depend on the model parameters.
[0026] In an advantageous further embodiment of the invention, it may be provided that the battery temperature is furthermore included as a model parameter of the vehicle battery model.
[0027] In a further advantageous embodiment, it is envisaged that the method further comprises a step of recognising at least one load event in the value of the measured quantity and limiting the value of the measured quantity to values surrounding the at least one load event in at least one value range.
[0028] A load event in the sense of the present invention is an event with a clearly high load of the vehicle battery. This is in particular a strong acceleration event, during which a high load of the battery is required within a short period of time, or a strong braking event, during which regenerative braking regenerates the kinetic energy of the vehicle into electrical energy for the vehicle battery. Also, for example, long uphill and / or downhill driving indicates a high probability of a load event on average.
[0029] It is further advantageously provided that in the step of simulating the vehicle battery, the physical parameters of the cell configuration are included in the vehicle battery model.
[0030] Vehicle batteries are often constructed in a modular way. The smallest unit of a vehicle battery is the individual cell. When several cells are connected in series, a "string" (also called a String) is obtained. When several strings are connected in parallel, they are called a "module." When several modules are connected together in parallel or series, or in a combination of parallel and series, they are called a "pack." If the cell configuration of the vehicle battery is known, that is, the number of cells in series and in parallel, especially in a pack, the battery volume can be adjusted in the simulation.
[0031] In a further advantageous embodiment of the method, the interruption condition is or corresponds to the difference between the simulated terminal voltage and the measured terminal voltage reaching, in particular partially or absolutely, a minimum and / or the simulated terminal voltage reaching a limit value, in particular when the simulated terminal voltage now only fluctuates infinitesimally.
[0032] Such a form of interrupt condition makes it possible to achieve a particularly practical and unintrusive analysis through the method according to the invention.
[0033] In a further advantageous embodiment of the method, the measurand recorded is selected from the following group of measurands: Battery current, terminal voltage, vehicle battery state of charge, minimum cell temperature, maximum cell temperature The cell temperature is the temperature measured in a cell of the vehicle battery. From one or more cell temperatures the battery temperature may be estimated. For example, an average value derived from the highest and lowest measured cell temperatures may be taken as the vehicle battery temperature value. Another possibility is to use the temperature of the coolant liquid used for cooling the vehicle battery as an approximation of the vehicle battery temperature.
[0034] In a further advantageous embodiment of the method, during the measurement run, the following run strategies are preferably performed as a function of the setpoint values: Tip-in, tip-out, full throttle acceleration, part load acceleration, regenerative braking, uphill driving and downhill driving are performed, the uphill driving and downhill driving being performed in particular for at least 30 seconds each, preferably for at least 10 seconds.
[0035] Further features and advantages are set forth in the description taken in conjunction with the drawings, in which the invention is at least partially illustrated diagrammatically. [Brief description of the drawings]
[0036] [Figure 1] 1 is an embodiment of a method for generating a virtual prototype of a vehicle. [Diagram 2] This is the configuration of a high-voltage storage battery. [Diagram 3] FIG. 1 is a circuit diagram of an electrical alternative model for simulation of a vehicle battery. [Figure 4] 1 illustrates an embodiment of a system for generating a virtual prototype of a vehicle. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] FIG. 1 shows an embodiment of a method S0 for generating a virtual prototype of a vehicle battery of a vehicle 1 based on data from road measurements.
[0038] For road measurements, a vehicle 1, preferably with at least partial electric drive, is used to carry out a measurement run on a road 2, in particular a road.
[0039] In particular, in a first operational step S1, the values of the measured quantities of the measurement run are detected. This can be carried out via a data interface, but also via sensors directly during the measurement run.
[0040] During the measurement run, depending on the electrical parameters to be determined, the following driving strategies can also be selected, for example: Tip-in, tip-out, full throttle acceleration, part load acceleration, regenerative braking, uphill driving and downhill driving are performed. In particular, uphill and downhill driving are performed for at least several minutes, preferably for at least 10 seconds, particularly preferably for at least 30 seconds.
[0041] These driving strategies are preferably carried out iteratively, so that each driving strategy is carried out at different states of charge and, particularly preferably, at different battery temperatures.
[0042] The measured quantities detected in the first work step S1 are preferably from the following groups for the measurement group: Select from Battery Current, Terminal Voltage, Battery State of Charge, Minimum Cell Temperature and Maximum Cell Temperature. In particular, the selection may also include all of the parameters described.
[0043] In the following optional step S1a, the detected measurements are classified, for example, according to the battery temperature and the state of charge. That is, for example, measurements recorded at similar battery temperatures are classified into the same category. The classification of the measurements according to the battery temperature may in particular be performed in steps of 5° C. or 10° C. In this example, all measurements recorded at battery temperatures between 20° C. and 25° C. may be classified into the same category. Similarly, the measurements may be classified according to the state of charge. In particular, the classification of the measurements according to the state of charge may be performed in steps of 5% of the full load capacity.
[0044] Further, in optional step S1b, the classified measured values are divided according to their classification. In the described example, the measured values can be divided into 20 categories of measured values in 5% increments in a classification according to the state of charge (from a state of charge of 0-5% to a state of charge of 95-100%). If measurement runs have not been performed for all states of charge of the vehicle, the number of categories will be reduced accordingly. The number of categories will be determined similarly for temperature.
[0045] The method preferably shows a number of simulation loops 110a...110n, which are preferably performed in parallel with one another, the number of loops being determined by the categories, e.g. state of charge and / or temperature, and the number of steps per category. For each step of a category, one simulation loop may be performed. The maximum number of simulation loops thereby corresponds to the product of the number of steps of each category with each other. For example, if there are 10 steps in the classification by temperature and 20 steps in the classification by state of charge, then a maximum of 200 simulation loops 110a,...110n will be performed for one measurement run.
[0046] In each simulation loop 110a,...,110n, advantageously, the electrical parameters of the vehicle battery model, such as the open circuit voltage, the load capacity in each charging and discharging state, the internal resistance, the RC resistance and the RC capacitance, are optimized. The calculated battery parameters are output corresponding to each loop and are combined with the battery parameters calculated from the other loops and finally taken into account in the vehicle battery model.
[0047] In detail, first, in a second working step S2, the vehicle battery is simulated by means of a vehicle battery model M. The vehicle battery model M includes the battery parameters and further physical characteristics of the vehicle battery. The vehicle battery model M therefore depends on these quantities. The further physical characteristics of the vehicle battery are advantageously the battery temperature and the state of charge. At least one value of the terminal voltage is output as a target value for this simulation.
[0048] In a third work step S3, which is also part of the first simulation loop 110a, at least one value of the terminal voltage measured in work step S1 is compared with the terminal voltage simulated in work step S2.
[0049] In a fourth work step S4, the vehicle battery model M is adjusted so that the value of the simulated parameter terminal voltage is as identical as possible to the value of the terminal voltage measured in the road measurement. For this purpose, the values of the battery parameters are preferably adjusted.
[0050] The working steps S2 to S4 are repeated for each of the simulation loops 110a, ..., 110n until an interruption condition is reached. Each simulation loop 110a, ..., 110n now generates partial battery parameters according to the respective classification of the simulation loop.
[0051] The interruption condition is in particular preset by an optimization problem, and advantageously the interruption condition is that the difference between the simulated terminal voltage, in the case of the first simulation loop 110 the terminal voltage during discharge, and the terminal voltage calculated on the basis of road measurements, reaches a partial or absolute minimum.
[0052] Furthermore, an interruption condition may be when a simulated parameter reaches a limiting value, in particular when the parameter can no longer vary infinitesimally.
[0053] In the next operational step S4a, partial battery parameters are collected and compiled. The optional step S4a is essentially carried out if a classification of the detected measured values has been carried out beforehand.
[0054] Finally, in a fifth work step S5, the values of the battery parameters of the vehicle battery model M are output to the vehicle battery model M, so that the values of the battery parameters can be taken into account in the vehicle battery model M. After classification, the vehicle battery model M builds a superset according to the classification.
[0055] If only steps S1, S2, S3, S4, and S5 are performed in the simulation loop 110a only, and optional steps S1a, S1b, and S4a are not performed, the method generates a virtual prototype of the vehicle battery having only a general set of parameters, rather than a superset of various parameters.
[0056] FIG. 2 shows how the high-voltage accumulator is assembled into a vehicle battery. The smallest unit of the high-voltage accumulator is a cell 22, which forms each accumulator unit. A number of cells 22 are connected in series to form a string 24. The voltages present in each cell 22 are added together in the series connection of the string 24 to obtain the total voltage. A module 26 is a parallel connection of a number of strings 24. This parallel connection allows the capacities of each string to be added together to obtain the total capacity. A number of modules 26 are connected in series and / or parallel to form a pack 28. Each of the units of the cell 22, the string 24, the module 26, and the pack 28 has only two connections. A vehicle battery consists of one or more packs 28.
[0057] 3 shows a circuit diagram of an electrical substitution model 30 for the simulation of a vehicle battery. A system boundary 31 of the substitution model 30 surrounds an open circuit voltage source Uocv 32, an internal resistance 33, and an RC element consisting of an RC resistance 34 and an RC capacitance 35. A current 36 flows through terminals 37. A terminal voltage 38 exists between the terminals 37. In the electrical substitution model, the open circuit voltage 32, the internal resistance 33, the RC resistance 34 and the RC capacitance 35 may essentially be a function of the state of charge and the vehicle battery temperature.
[0058] 4 shows an embodiment of a system 10 for generating a virtual prototype of a vehicle battery based on data of road measurements, the system comprising means 11, 12, 13, 14 and 15 for parameterization of a virtual prototype vehicle battery model M. The means 11, 12, 13, 14 and 15 for parameterization are here provided for iteratively and successively calculating, in particular through a cascaded software-in-the-loop simulation, battery parameter values of the vehicle battery model M in a simulation loop in which the electrical parameters of the vehicle battery model M are optimized based on measured values of the road measurements through a comparison of the simulated parameter values with parameter values calculated from the road measurements.
[0059] In particular, a system 10 is provided for carrying out a method S0 according to Fig. 1. Advantageously, but not necessarily, the system 10 here comprises means 11 for calculating at least one value of a terminal voltage on the basis of values of the measured quantities recorded during a measurement run.
[0060] Furthermore, the system 10 advantageously comprises means 12 for simulating the vehicle battery by means of a vehicle battery model M, where the vehicle battery model M includes at least the following battery parameters of the vehicle battery: Open circuit voltage, load capacitance when charging, load capacitance when discharging, internal resistance when charging, internal resistance when discharging, RC resistance when charging, RC resistance when discharging, RC capacitance when charging, RC capacitance when discharging, There, at least the value of the terminal voltage is output as a target value.
[0061] Additionally, the battery temperature and the state of charge of the vehicle battery may be included in the battery model M.
[0062] Furthermore, advantageously, the system 10 comprises means 13 for comparing at least one value of the terminal voltage calculated on the basis of road measurements with a value of a simulated terminal voltage.
[0063] Further advantageously, the system 10 comprises means 14 for adjusting the vehicle battery model M in order to match the simulated terminal voltage to a terminal voltage calculated on the basis of road measurements by varying the values of the battery parameters.
[0064] The battery parameters include open circuit voltage, load capacity when charging, load capacity when discharging, internal resistance when charging, internal resistance when discharging, RC resistance when charging, RC resistance when discharging, RC capacity when charging, and RC capacity when discharging.
[0065] Furthermore, the system 10 advantageously comprises an interface 15 for the output of values for battery parameters of the vehicle battery model M, and means for parameterization are provided for adjusting the vehicle battery model M until an interruption condition is reached.
[0066] The means 11, 12, 13, 14 and 15 of the system 10 are advantageously part of a data processing device. Advantageously, the method S0 is performed automatically and / or computer-implemented by such a data processing device.
[0067] The described methods 11, 12, 13, 14 and 15 are in particular also arranged to implement a second simulation loop 120 and a third simulation loop 130 of the method S0.
[0068] It should be noted that these embodiments are merely examples, and should not limit the scope of protection, application, or configuration in any way, but rather provide a guide for a person skilled in the art to realize at least one of the embodiments through the above description, in which various modifications, particularly modifications of the functions and arrangements of the components described, may be made without departing from the scope of protection resulting from the combination of the claims and equivalent features. [Explanation of symbols]
[0069] 1 Vehicle, vehicle battery 2 track 10. System 11, 12, 13, 14, 15 means 22 Cells 24 String 26 Modules 28 pack 30 Electric Replacement Model 31 System Boundaries 32 Open circuit voltage 33 Internal Resistance 34 RC resistance 35 RC capacity 36 Current 37 Terminal 38 Terminal Voltage 110a, 110n simulation loop 120 Second Simulation Loop 130 Third Simulation Loop S0 method S1, S2, S3, S4, S5 (work) steps S1a, S1b, S4a optional steps M Vehicle Battery Model
Claims
1. A computer-implemented method (S0) for generating a virtual prototype of a vehicle battery based on data from road measurements, comprising: S1) detecting the values of the measurands of the measurement trip, including the value of the terminal voltage; S2) simulating a vehicle battery using a vehicle battery model (M), wherein the vehicle battery model (M) includes battery parameters including an open circuit voltage (32), a load capacity at discharge, an internal resistance at discharge (33), an RC resistance at discharge (34), and an RC capacity at discharge (35), and wherein at least the value of the terminal voltage (38) is output as a target value; S3) comparing at least one value of the terminal voltage (38) detected in step S1 with a value of the terminal voltage (38) simulated in step S2; S4) adjusting the vehicle battery model (M) to match the simulated terminal voltage (38) to the calculated terminal voltage (38) based on the road measurements by varying the values of the battery parameters; S5) outputting values for the battery parameters of the vehicle battery model (M); The method repeats steps S2 to S4 until an interrupt condition is reached.
2. 2. The method of claim 1, wherein the vehicle battery model (M) further includes the following battery parameters: load capacity when charging, internal resistance when charging (33), RC resistance when charging (34), and RC capacity when charging (35).
3. 2. The method of claim 1, wherein the vehicle battery model (M) further includes the following battery parameters: load capacity when no current is flowing, internal resistance when no current is flowing (33), RC resistance when no current is flowing (34), and RC capacitance when no current is flowing (35).
4. The method of claim 1 , further comprising: including a state of charge of the vehicle battery in a model parameter of the vehicle battery model (M).
5. The method of claim 1 , further comprising: including a battery temperature as a model parameter of the vehicle battery model (M).
6. further recognizing at least one load event in the value of the measured quantity; limiting the value of said measured quantity to values surrounding said at least one load event in at least one defined value range; 2. The method of claim 1, comprising:
7. The method of claim 1 , wherein in step S2, physical parameters of a cell configuration are included in the vehicle battery model.
8. 2. The method of claim 1, wherein the interruption condition is that the difference between the simulated terminal voltage (38) and the calculated terminal voltage (38) reaches a partial or absolute minimum and / or that the simulated terminal voltage (38) reaches a limit value.
9. The method according to claim 8, wherein the minimum is a partial minimum or an absolute minimum, and the limit value of the simulated terminal voltage (38) is reached when the terminal voltage (38) no longer fluctuates infinitesimally.
10. The measurand detected in step S1 is selected from the following group of measurands: Battery current (36), terminal voltage (38), battery state of charge, minimum cell temperature, and maximum cell temperature, 2. The method of claim 1, wherein the compound is selected from the group consisting of:
11. During the measurement run, at least the following run methods are performed: The method of claim 1 , wherein tip-in, tip-out, full throttle acceleration, part load acceleration, regenerative braking, uphill driving, and downhill driving are implemented.
12. The method of claim 11, wherein the uphill running and the downhill running are performed for at least 30 seconds, or at least 10 seconds.
13. 10. A method for analyzing a vehicle battery, wherein the vehicle battery is simulated using a virtual prototype of the vehicle battery, the virtual prototype being generated using the method of claim 1.
14. A computer program or storage medium having instructions which, when carried out by a computer, cause the computer to carry out the method according to any one of claims 1 to 13.
15. 1. A system (10) for generating a virtual prototype of a vehicle battery (1) based on data from road measurements, the system (10) comprising means (11, 12, 13, 14, 15) for parameterizing a vehicle battery model (M) of the virtual prototype with battery parameters, wherein said means (11, 12, 13, 14, 15) are provided for parameterizing and iteratively and continuously calculating the load capacity, the internal resistance (33) during charging and discharging, and the RC resistance (34) values of the vehicle battery model (M) through comparison of simulated parameter values with parameter values calculated by the road measurements in a simulation loop that optimizes the electrical parameters of the vehicle battery model (M) through software-in-the-loop simulation based on measured values of the road measurements.
16. The system (10) of claim 15, wherein the software-in-the-loop simulation is cascaded.
17. 16. A system (10) for generating a virtual prototype of a vehicle battery (1) based on data from road measurements, according to claim 15, comprising means (11, 12, 13, 14, 15) for parameterization, said means (11, 12, 13, 14, 15) for parameterization comprising: means (11) for calculating at least one value for the terminal voltage based on the values of the measured quantities recorded during the measurement run; Means (12) for simulating said vehicle battery using a vehicle battery model (M), wherein said vehicle battery model (M) includes at least the following physical characteristics of said vehicle battery (1), namely: The load capacity, the internal resistance (33) during charging, and the internal resistance (33) during discharging of the vehicle battery; RC resistance (34) during charging, and RC resistance (34) during discharging, RC capacitance during charging (35), and RC capacitance during discharging (35), as a parameter, A means for outputting at least the value of the terminal voltage (38) as a target value; means (13) for comparing at least one value of the terminal voltage calculated based on said road measurements with a value of said simulated terminal voltage (38); means (14) for adjusting the vehicle battery model (M) to match the simulated terminal voltage (38) to a terminal voltage (38) calculated based on the road measurements by varying the parameters; an interface (15) for outputting values for battery parameters of the vehicle battery model (M); Including, The system, wherein the means for parameterization is arranged to adjust the vehicle battery model (M) until an interruption condition is reached.