DE102012007989A1 - Method for controlling power dynamics of battery of electrical propelled vehicle, involves setting maximum output current of battery less than specific current output value, if load value amount is larger than load threshold value - Google Patents

Abstract

The method involves calculating a time evolution of current difference between a battery moment and a load value associated with first current output value of a battery (2) of an electrical propelled vehicle (1). The maximum output current of the battery is set equal to second current output value, if the calculated amount of load value is less than or equal to a load threshold value. The maximum output current of battery is set to less than second current output value, if calculated amount of load value is larger than load threshold value. An independent claim is included for a device for controlling power dynamics of battery of electrical propelled vehicle.

Description

The present invention relates to a method and a device for controlling the power dynamics of the battery of an electrically driven vehicle.

In order to provide efficient alternatives to vehicles with an internal combustion engine, high-voltage batteries have been developed in battery technology. A high-voltage battery module is composed of individual cells, which are connected in series with a voltage of one to two volts, so that the summation of the individual voltages results in the high-voltage voltage required for the drive.

The peak power of a purely electrically driven vehicle with such a high-voltage battery is due to the physical and chemical processes in the high-voltage battery only for a limited period available. Thereafter, the power dissipated by the battery must be reduced to a lower continuous power, which is then available for a much longer period. In today's automotive high-voltage batteries, peak power is typically available in the sub-minute battery side. The continuous power, however, is orders of magnitude above, d. H. typically on the order of an hour or at least a good part of it. If the peak power has been delivered by the battery for the maximum possible period of time, a recovery phase is required, after which the peak power is again available in the short term.

Thus, the driver is only a certain amount of energy to exceed the continuous power available. This variable energy amount, which is also called peak power reserve, depends in particular on the load history with outputs above the continuous power and the recovery phases.

The continuous power, the peak power and thus also the maximum possible peak power reserve depend on the operating point of the battery. The operating point is determined in particular by the temperature, the state of charge (SoC = State of charge) and the state of aging (SoH = State of Age). For this purpose, power characteristic curves are provided which represent the continuous power and possible peak power at a defined operating point independently of the load history. The battery parameters at a defined operating point are semi-permanent, i. H. they change only slowly against the rapidly changing peak power reserve. The battery parameters at a defined operating point can thus be regarded as constant for the instantaneous power potential of the battery. The question of whether and when a performance limitation compared to the peak performance is to be expected is then clarified by the concrete load history. Furthermore, other involved components such. B. power electronic modules or an engine control unit lead to a performance restriction.

The power dynamics, d. H. the currently available in the period ahead are available power potential of the battery, so unlike internal combustion engines is not constant and also depends on the past load history. Therefore, it requires a traceable control of the power dynamics in electrically driven vehicles, so that the driver of the vehicle especially for short-term maneuvers, eg. As for overtaking maneuvers or threading on a highway, the performance of the vehicle drive can intuitively understand.

In particular, it should also be taken into account that the power that can be delivered by the battery is relevant for the driving performance, but that the battery-internal processes are dominated by the battery current. The DE 10 2009 049 589 A1 describes a method in which by means of an equivalent circuit diagram, the power forecast is solved by means of a differential equation. In the method, first the maximum permissible operating voltage and the maximum permissible operating current are predicted. To account for the history, the bias value at the capacitor of the battery is taken into account at the time of the prediction calculation, and then the measured current and voltage values are used to solve the differential equation. The performance forecast is used in particular for predictive power control. If the power reserve is insufficient for the forecast period, the power will be reduced to approx. B. limited before an acceleration process or continuously downshifted during an acceleration process to avoid a sudden, noticeable to the driver performance degradation.

A disadvantage of this method is that the solution of a differential equation is comparatively complex and places great demands on the executing arithmetic unit in real-time operation.

It is the object of the present invention to provide a control concept of the power dynamics of the battery of an electrically driven vehicle, which is easy and inexpensive to implement and which provides the driver in a timely period a reproducible and intuitive traceable power potential of the vehicle battery.

This object is achieved by a method having the features of claim 1 and by an associated apparatus having the features of claim 10. Advantageous training and further developments emerge from the dependent claims.

In the method of controlling the power dynamics of the battery of an electrically-powered vehicle, a first and second current output values associated with the battery are determined, of which the second current output value is higher than the first current output value, and the current output from the battery is measured. Depending on the temporal evolution of the current delivered by the battery, the maximum current that can be delivered by the battery is predetermined, wherein a charge value is calculated from the time evolution of the current difference between the current current output by the battery and the first current output value associated with the battery. In this case, if the calculated charge value is less than or equal to a set charge limit, the maximum current deliverable by the battery is set equal to the second current output value associated with the battery, and it becomes if the calculated charge value is greater than the set charge limit , the maximum current that can be delivered by the battery as a function of the calculated charge value is set smaller than the second current output value associated with the battery. The consideration of the temporal evolution of a current size has the advantage that the battery internal processes is better than in a performance consideration of the case, the battery power can still be calculated from the product of voltage and current always.

The determination of the maximum current output is a controlling limitation that can be initiated before the battery internal processes would reduce the current output. This has the advantage that it comes not abruptly and without consideration of the history of a power and thus a power limitation.

In an advantageous embodiment of the method according to the invention, the first current output value of the continuous current which can be emitted at the present operating point and the second current output value of the peak current that can be delivered to the present operating point are. Through the relationship "power equal to voltage times current", these values physically correspond to the power levels between which the available power moves to the current operating point. These two performance levels thus determine the operational area for driving the vehicle. Alternatively, however, other current output values can be selected, for. B. a current output value slightly below the deliverable continuous current at the present operating point, so that a slow reduction of the deliverable continuous current over time is taken into account.

In particular, the charge value is calculated as a first integral of the current difference between the current current output from the battery and the first current output value associated with the battery over a first time interval. The integration over time provides an accurate and reproducible charge value by which the instantaneous battery charge has been reduced relative to the fully charged battery at the particular operating point. For a given battery voltage, this charge value can be converted into an energy amount and set in relation to the peak power reserve mentioned above.

In particular, it is provided that the first time interval over which the current difference is integrated is reinitialized at the time when the first integral of the current difference has become negative over the previous time interval and the current current output by the battery exceeds the first current output value. This ensures that when the battery is fully recovered, i. H. when the battery is fully charged for that particular operating point, the charge value is only recalculated when an event occurs that actually has a higher current output than the first current output value. In particular, computationally no non-existent charge buffers are generated by the integral is purely computationally negative by low current outputs and thus the charge value would only after a certain time of a load with currents higher than the first current output value zero and then again positive. On the other hand, it is ensured that in the event of permanent alternating load below and above the first current output value, possibly even past peak power reserve utilizations are taken into account if a complete recovery of the battery has never taken place.

In an advantageous embodiment of the method according to the invention it is provided that, if the calculated charge value is greater than the fixed charge limit, a second time interval is initialized and a second integral of the current difference between the current output from the battery current and the first current output value via the second time interval is calculated. The maximum deliverable by the battery current is then reduced from the second current output value linearly to the value of the second integral of the current difference. It is expedient for the maximum current that can be delivered by the battery to be reduced at most to the first current output value, since this is the continuous current that can be emitted by the vehicle battery equivalent. The linear reduction takes place mathematically by the scaling with a time factor in order to achieve a dimensional value of a current value. The beginning of such a reduction of the maximum deliverable from the battery current, which is also referred to as a so-called "de-rating" can be adapted to the particular application. The maximum deliverable current can take place in particular before such a time at which it would come from a battery technology point of view to a current limit. The maximum deliverable current is z. B. therefore limited because harnesses that transfer the power from the battery to the electric drive, or other involved components such. B. power electronics modules, are designed for a shorter period of time for the second current output value.

In one embodiment variant of the method according to the invention, it is provided that the performance map of the battery has been calculated and / or simulated over a range of operating points, determines the instantaneous operating point and an associated first and second power output value is determined and the internal resistance of the battery at the operating point and the open circuit voltage Battery is determined. The first and second current output values are then calculated as a solution of a quadratic equation from the first and second power output values, the internal resistance and the open circuit voltage of the battery. The performance maps are pre-calculated more accurately than electricity maps. The derivation of the resulting characteristic diagrams results in particular from the simplified equivalent circuit of a battery with an operating point-dependent internal resistance R ₀ and the resulting open circuit voltage U ₀ . The current output value I _x at an operating point results from the power value P _x (x stands here in particular for the indices D and S) according to the equations U = U ₀ -R ₀ × I _× (I) P _x = U * I _x (II) P _x = U ₀ × I _× R ₀ × I _× ² (III), where equation (III) is the quadratic equation to be solved.

The first and second current output values can also be determined without solving this quadratic equation. For this purpose, a power map of the battery was calculated and / or simulated over a range of operating points. The instantaneous operating point is determined and an associated first and second current output value is determined and the operating voltage of the battery is measured. The calculation of a current map is not possible in a reproducible manner, so that in operation usually comes to discrepancies between theoretically calculated and actual current output values. The theoretical power output resulting from the first and second current output values and the operating voltage is therefore calculated and compared with the actual power output. The first and second current output values associated with the battery and / or the current characteristics of the battery can then be corrected as a function of this comparison. This variant requires fewer computational resources than computing the solution of a quadratic equation. Accordingly, it can be carried out quickly without great demands on the computing capacities.

Both variants can also be used in parallel. For example, the first and second current output values are each determined with a different one of the two variants. It is also possible that the calculation is performed only sporadically by solving the quadratic equation, e.g. B. once per minute, and the other variant is used for intermediate calculation.

The first and second current output values are "semi-permanent", i. H. they change gradually during operation. They are advantageously updated continuously, i. H. constantly monitored and determined again and again at the valid operating point. Alternatively, they are only sporadic, z. For example, triggered by an event.

In one embodiment of the method according to the invention, the power dynamics of the battery is visualized by a variable that can be represented in one dimension, wherein the calculated charge value is assigned a fixed predetermined proportion of the variable that can be represented in one dimension. This allows the driver of the vehicle quickly and intuitively capture the upcoming performance dynamics. The calculated charge value can represent part of a visualized value range, eg. 100%, if the charge value is zero, and 60% if the charge value is equal to the charge limit, d. H. at the beginning of the de-rating, and 40% when the deliverable power is reduced to the first power output value. The range 0% to 40% is reserved for the range of power dynamics in which the discharge of the battery has progressed so far that the valid over a wide range of operating parameters continuous power level can no longer be maintained.

Such a visualization is particularly clear because the driver is visualized various information of the power dynamics over a single one-dimensional size. This one-dimensional size can then in a simple manner as z. As number or as a pointer or bar chart.

The inventive device for controlling the power dynamics of the battery of an electrically driven vehicle comprises a battery monitoring device for detecting at least two different associated with the battery power output values, a measuring device for measuring the output of the battery power and a computing unit which is connected to the measuring device and by means of which From the temporal evolution of the current difference between the current output from the battery, the current and the battery associated with the first current output value, a charge value can be calculated. The device further comprises a control unit, which is connected to the battery monitoring device and the arithmetic unit, by means of which, depending on the temporal evolution of the current emitted by the battery of the maximum deliverable by the battery current can be predetermined, wherein, if the calculated charge value is smaller or is equal to a set charge limit, the maximum battery deliverable current through the controller is set equal to the second current output associated with the battery, and wherein, if the calculated charge value is greater than the predetermined charge limit, the maximum of the battery the deliverable current can be set by means of the control unit in dependence on the calculated charge value smaller than the second current output value associated with the battery. The device according to the invention is particularly suitable for carrying out the method according to the invention. It therefore also has the advantages of the method according to the invention.

Furthermore, according to the invention, a vehicle with at least one partial electric drive is equipped with such a device for controlling the power dynamics of the battery. It may be vehicles with purely electric drive or electric auxiliary drive, such. B. so-called hybrid drives.

The invention will now be explained in more detail by means of embodiments with reference to the figures.

1 shows an electrically driven vehicle, which is equipped with a device for controlling the power dynamics of the vehicle battery according to an embodiment of the invention,

2 shows a device for controlling the power dynamics of the battery of an electrically driven vehicle according to an embodiment of the invention,

the 3 and 4 show by way of example the performance characteristics of the peak power and the continuous power of a high-voltage battery whose power dynamics are controllable according to the invention,

5 shows an example of a temporal evolution of the delivered and the maximum deliverable current in connection with the inventive method and

6 shows a possible visualization of the power dynamics of the battery of an electrically driven vehicle according to an embodiment of the method according to the invention.

In the 1 is an electrically driven vehicle 1 shown, which with a device for controlling the power dynamics of the battery 2 of the vehicle 1 equipped according to an embodiment of the invention. The electrically powered vehicle 1 is, as is well known, with one with the battery 2 connected electric motor 5 to drive the vehicle 1 and with one with the electric motor 5 connected engine control 6 fitted.

An embodiment of the device according to the invention is shown schematically in the 1 and 2 shown. It comprises a sensor device 3 for sensory detection of the operating parameters of the battery 2 and a current history meter 4 for detecting the current output history of the battery 2 , both with the battery 2 are connected. The device according to the invention further comprises a control unit 7 that with the sensor device 3 and current history meter 4 is connected and by means of which the maximum deliverable by the battery current I _{Max can be} specified.

The control unit 7 is with a display device, for. B. the multifunction display 10 of the vehicle 1 connected to visualize the performance dynamics. Further, the control unit 7 with the engine control 6 coupled, for example, integrated into this.

The sensor device 3 In particular, detects the temperature T, the state of charge SOC and the aging state SOH of the battery 2 , From these operating parameters of the battery 2 an operating point is determined. For possible operating points are characteristic curves in the sensor device 3 stored, by means of which for a given operating point of the continuous current I _D , from which a continuous power PD is calculated below, and the peak current I _S , from which a peak power PS is calculated below, can be determined.

From the difference of the peak power PS and the continuous power PD at the respective operating point is in particular a maximum Peak power reserve MSLR is calculated by multiplying this power difference PS - PD by a time factor. This time factor must be adapted to the respective vehicle configuration. The maximum peak power reserve MSLR is dimensionally an amount of energy which can be used for a temporary additional power in addition to the continuous power PD.

In the 3 and 4 are exemplary the Leistungsungskennkurve 20 the peak power PS and the power characteristic curve 21 the continuous power PD of a high-voltage battery 2 depending on the battery parameters temperature T and battery charge SOC shown. These were obtained by theoretical calculations or simulation. It can be seen that the peak power PS is typically about twice as high as the steady state power PD and that peak power PS and steady state PD are nearly constant for a wide range of battery parameters. Only at low battery charges SOC (~ 30%) and / or at low temperatures (T <0 ° C), there are significant performance losses.

From the performance characteristics 20 . 21 the peak current I _S and the continuous current I _{D can be} calculated. For this purpose, the current operating point is determined and it is the associated continuous power PD and peak power, PS determined. Thereafter, the internal resistance R _{0 of} the battery 2 at the operating point and the open circuit voltage U _{0 of} the battery 2 certainly. From the quadratic equation described in the general part (x again stands for the indices D and S) P _x = U ₀ .I _x - R ₀ .I _x ² Continuous current I _D and peak current I _{S are} calculated as the solution of this equation.

Alternatively, current characteristics or current characteristics over a wide range of operating points can be calculated in advance (not shown). Here, however, the problem arises that the history of the battery, ie the past use and aging, can be considered more difficult and thus leads to partially un reproducible results. In such a case, the predicted performance value must be corrected by a comparison measurement. This can be achieved by determining the instantaneous operating point and determining the associated continuous current I _D and peak current I _S and the operating voltage U of the battery 2 is measured. The theoretical power output resulting from these current and voltage values is calculated and compared to the actual power output. From this comparison results in a correction term, with which the power map of the battery 2 can be corrected.

The actual deliverable current from the battery 2 depends on the current delivery history. The time scales with which the actual output current during normal operation of the vehicle 1 changes, ie in the range of seconds or fractions of minutes, are one to two orders of magnitude smaller than the time scales, which change the operating point of the deliverable current of the battery 2 changes (typically in the range of a few minutes to hours). Therefore, the persistent current I _D and peak current I _S determined at a given operating point, and thus also power values PD, PS, can be considered to be nearly constant when compared to the current output history.

The electricity history meter 4 detects the moment of the battery 2 delivered current I _is and the time evolution thereof, so the current output history of the battery 2 , over a time interval. The detection of the current delivery history will be described with reference to FIG 5 and explained in more detail in connection with the method according to the invention.

The of the sensor device 3 and the current history meter 4 captured data is transmitted via the data bus 9 in the vehicle 1 to the control unit 7 and to a computing unit integrated therein 8th transmitted. By means of the arithmetic unit 8th is from the temporal evolution of the current difference between the actual momentary of the battery 2 delivered current I _Ist and the continuous current I _D calculated a charge value Q and from the maximum of the battery 2 deliverable current I _max given, as will be explained in more detail in connection with the method according to the invention. Depending on how long and to what extent in a past time interval the actually delivered current I _ist higher than the continuous current I _D the higher the charge value Q is calculated until it reaches a threshold value above which a controlled current limit, the so-called De Rating, is initiated. In order to consider a creeping reduction of the continuous current I _D and peak current I _S for longer periods, these are continuously updated. A possibly higher current difference causes the charge value Q to be larger.

Incidentally, the charge value Q can be converted at any time into an energy equivalent by multiplication with the battery voltage U and can be delivered at short notice from a maximum available energy amount which is additionally available for the continuous power PD. The charge value Q corresponds to the shortage of the peak power reserve SLR to the maximum peak power margin MSLR.

The inventive method will now be described by means of embodiments and with reference to the 5 and 6 explained in more detail. to Embodiment of the method according to the invention, the device of the invention described above can be used, which is also referred to in the following.

In the 5 is an example of a Stromabgabehistorie 22 shown. Initial situation is that the electric motor 5 of the vehicle 1 For a sufficiently long period only a limited power average below the continuous current I _D from the battery 2 has called. The battery 2 has fully regenerated according to the operating point, so that the peak current I _{S is available} for a maximum period of time. The vehicle 1 For example, it was restarted just after a break in operation or it was before with only a small load on the battery 2 hazards.

About the sensor device 3 becomes the continuous current I _D and the peak current I _{S of} the battery 2 determined. Further, from the current history meter 4 the momentary of the battery 2 delivered current I _is measured continuously and with a corresponding time stamp as z. B. average over a short time interval in seconds or sub-second range buffered. These data are sent to the control unit 7 and to the arithmetic unit 8th transmitted. The control unit 7 gives the value of the current I _{max coming} from the battery 2 may be submitted, before and transmitted to the engine control 6 ,

At time t0 now the vehicle 1 so accelerates that the electric motor 5 a higher current I _is than the continuous current I _D from the battery 2 retrieves. Thereafter, the time interval for detecting the current output history becomes 22 the battery 2 reinitialized. The time course of the current delivery history 22 is through the current history meter 4 recorded and the associated data to the arithmetic unit 8th transmitted. In the arithmetic unit 8th the current difference between the output current I _actual and the continuous current I _{D is} integrated in time and thus the charge value Q is calculated. In the further course follow different current outputs I _Is the battery 2 , which are temporarily below the continuous current I _D. At a point in time t1, the current output was reduced in such a way that the integral of the current difference between actual output current I _actual and the continuous current I _D becomes mathematically negative over the time interval from t0 to t1. This corresponds to a complete renewal of the battery 2 at the present operating point.

At time t2, it will be from the battery 2 delivered current I _is again greater than the continuous current I _D , whereupon the time interval for calculating the charge amount Q is reinitialized and thus the calculation of Q starts anew at zero. In the further course follow different current outputs I _Is the battery 2 , which are temporarily below, but on average above the continuous current I _D , so no complete regeneration of the battery 2 more is done.

For example, at time t3, the charge value Q reaches 40%, at time t4 80%, at time t5 93% and at time t6 100% of a predetermined maximum charge value Q _Max . The maximum charge value Q _Max represents a charge reserve (or, when multiplied by the battery voltage U, an energy reserve, ie the maximum peak power reserve MSLR). The maximum charge value Q _Max is like the maximum peak power reserve MSLR to the battery 2 customized.

Conveniently, the maximum charge value Q _{Max is} set lower than the charge value that would be the maximum possible for battery-technical reasons. This is in particular the reason that the harnesses, which is the current I _Is from the battery 2 to the electric motor 5 or other components involved, such as B. power electronics modules are designed for such a higher electrical current only for a shorter period. The one from the battery 2 delivered current I _ist must then be reduced in order to prevent damage to the wiring harness or the components involved by overload.

In today's vehicle configurations 30 s-40 s, a peak current I _S can typically be delivered. A sudden drop in power from the peak power I _S corresponding peak power PS to the continuous current I _D corresponding to the continuous power PD is not desirable. On the one hand, such a drop in performance is perceived by the driver as negative. On the other hand, a maneuver started with the peak power PS could only be completed with greatly reduced power.

According to the invention, therefore, an electronic control is provided, which down-regulates the maximum current I _{max can be} anticipated from a value of the peak current I _S continuously or stepwise to the level of the continuous current I _D.

Until the time t4, the predetermined value of the current I _max , as specified by the control unit 7 maximum may be discharged from the battery, equal to the peak current I _S set. At time t4, the charge value Q now reaches the charge limit value Q _Gr = 80% of the maximum charge value Q _max , so that the successive power limitation, the so-called de-rating, is started. For this purpose, from the time t4 to a second integral of the current difference between the current of the battery 2 output current I _is calculated and the continuous current I _D. The current I _Max will then first by the arithmetic unit 8th calculated so that the value of the peak current I _{S is} linearly reduced by the value of the second integral of the current difference.

The maximum of the battery 2 deliverable "allowed" current I _Max is reduced until it has been reduced to the value of the continuous current I _D. This occurs at time t6 at which the charge value Q has reached the maximum charge value Q _Max .

In the case shown, the maximum permissible current I _{Max is} actually actually emitted in the time interval between the times t4 to t6. As a result, the value of the second integral does not increase linearly with time, but results in an exponential decay of the maximum permissible current I _max until time t6. The de-rating is therefore relatively "soft", without a sudden performance slump occurs.

The performance dynamics are expressed and visualized by means of a performance indicator through a one-dimensional representable size. The performance indicator can take a percentage between 0% and 100% and is calculated as follows:
For a first fraction up to the PD / PS ratio, the performance indicator runs as a percentage of the peak horsepower PS, according to the available power. B. to 50%, when the peak power PS is twice as large as the continuous power PD. If the available power is higher than the continuous power PD, then the performance indicator is composed of the sum of the first part, ie PD / PS and a second part. This second component is calculated from the difference between the maximum charge value Q _Max and the charge value Q divided by the maximum charge value Q _Max and multiplied by the remaining percentage 100% (1-PD / PS), in this case also 50%. For the regenerated battery, the charge value Q is zero and thus the second component is maximum. The second fraction shrinks with increasing charge value Q until the maximum charge value Q _{Max is} reached at which of the control unit 7 predetermined maximum current I _{Max is} limited to the continuous current I _D and thus only the continuous power PD is available.

In the 6 The performance indicator is indicated by a power dynamics bar 13 visualized. Related to the 5 time t2-t6 becomes the power dynamic bar 13 dynamically changed according to the associated available powers, currents and the charge value Q. The visualization is done by filling the bar 13 or by any other suitable marking or emphasis, e.g. B. by using two colors, as is known from bar displays per se. The first part of the performance indicator will be in a first display area 16 visualized, the second part of the performance indicator in a display area 15 , The second display area 15 becomes proportionate, ie in the area 15A , displayed by the ratio (Q _Max - Q) / Q _Max , with the remaining range 15B is not highlighted accordingly.

The first display area 16 is fully displayed as long as the continuous current I _D and the associated continuous power PD is still available. Only when falling below the continuous power PD, z. B. with increasing discharge of the battery 2 during operation, this area will also be 16 only proportionately represented to the extent that the actual power has fallen in proportion to the continuous power PD.

LIST OF REFERENCE NUMBERS

1

electrically powered vehicle

2

High-voltage battery

3

Sensor device for operating parameters

4

Current histories meter

5

electric motor

6

motor control

7

control unit

8th

computer unit

9

Data bus in the vehicle

10

Multifunction display

11

round instruments

12

freely programmable display field

13

Power dynamic bar

14

Display area for third dynamic range

15, 15A, 15B

Display area for second dynamic range

16

Display area for first dynamic range

17

Warning symbol for first dynamic range

20

Top performance curve of a high-voltage battery

21

Continuous power of a high-voltage battery

22

Current Output History

PS

Top performance

PD

continuous power

I _D

continuous current

I _S

peak current

I _max

maximum deliverable current

I _N

nominal power

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102009049589 A1 [0007]

Claims (10)

Method for controlling the power dynamics of the battery ( 2 ) of an electrically driven vehicle ( 1 ), in which - one with the battery ( 2 ) associated first and second current output value (I _D , I _S ) are determined, of which the second current output value (I _S ) is higher than the first current output value (I _D ), - the current of the battery ( 2 ) emitted current (I _actual ) is measured and - depending on the temporal evolution of the battery ( 2 ) current (I _actual ) the maximum of the battery ( 2 ) can be output current (I _Max ) is given, - from the temporal evolution of the current difference (I _actual - I _D ) between the momentary of the battery ( 2 ) output current (I _actual ) and with the battery ( 2 ) Associated first current output value (I _D) a charge value (Q) is calculated, - wherein, if the calculated amount of charge (Q) is less than or equal to a set charge limit value (Q _Gr), the maximum (from the battery 2 ) deliverable current (I _max ) equal to the second with the battery ( 2 ) Associated current output value (I _S) is set, and - wherein, if the calculated amount of charge (Q) is greater than the predetermined charge limit value (Q _Gr), the maximum (of the battery can be output current I _Max) as a function of the calculated Charge value (Q) smaller than the second one with the battery ( 2 ) associated current output value (I _S ) is set. Method according to Claim 1, characterized in that the first current output value of the continuous current (I _D ) which can be output to the present operating point and the second current output value of the peak current which can be output to the present operating point (I _S ) are Ist. Method according to one of claims 1 or 2, characterized in that the charge value (Q) as a first integral of the current difference (I _actual - I _D ) between the momentarily of the battery ( 2 ) output current (I _actual ) and with the battery ( 2 ) associated first current output value (I _D ) over a first time interval (t0-t4) is calculated. Method according to claim 3, characterized in that the first time interval (t0-t6), over which the current difference (I _actual - I _D ) is integrated, is reinitialized at the time (t2), if - the first integral of the current difference (I _Is - I _D ) has become negative over the previous time interval and - the momentarily of the battery ( 2 ) output current (I _actual ) exceeds the first current output value (I _D ). Method according to one of the preceding claims, characterized in that - if the calculated charge value (Q) becomes greater than the set charge limit value (Q _Gr ), a second time interval (t4-t6) is initialized, - a second integral of the current difference (I _is - I _D ) between the momentarily from the battery ( 2 ) Current output (I _actual) and the first current output value (I _D) over the second time interval (t4-t6) is calculated, and - the maximum (from the battery 2 ) Abschaltbare current (I _Max ) from the second current output value (I _S ) is linearly reduced to the value of the second integral of the current difference (I _actual - I _D ), - the maximum of the battery ( 2 ) Deliverable current (I _Max) at most to the first current output value (I _D) is reduced. Method according to one of the preceding claims, characterized in that - the performance map ( 20 . 21 ) of the battery ( 2 ) was calculated and / or simulated over a range of operating points, - the instantaneous operating point is determined and an associated first and second power output value (P _D , P _S ) is determined, - the internal resistance (R ₀ ) of the battery ( 2 ) at the operating point and the open circuit voltage (U ₀ ) of the battery ( 2 ) and the first and second current output values (I _D , I _S ) as a solution of a quadratic equation from the first and second power output values (P _D , P _S ), the internal resistance (R ₀ ) and the open circuit voltage (U ₀ ) Battery ( 2 ) be calculated. Method according to one of the preceding claims, characterized in that - a current characteristic diagram of the battery ( 2 ) was calculated and / or simulated over a range of operating points, - the instantaneous operating point is determined and an associated first and second current output value (I _D , I _S ) is determined, - the operating voltage (U) of the battery ( 2 ) is calculated, - the theoretical power output resulting from the first and second current output values (I _D , I _S ) and the operating voltage (U) is calculated and compared with the actual power output, and - that with the battery ( 2 ) associated first and second current output value (I _D , I _S ) and / or the current map of the battery ( 2 ) is corrected as a function of this comparison. Method according to one of the preceding claims, characterized in that the first and second current output value (I _D , I _S ) are continuously updated. Method according to one of the preceding claims, characterized in that the power dynamics of the battery ( 2 ) by a one-dimensional representable size ( 13 ), whereby the calculated charge value (Q) has a fixed predetermined proportion ( 15 ) of the one-dimensional representable quantity ( 13 ). Contraption ( 3 . 4 . 7 . 8th ) for controlling the power dynamics of the battery ( 2 ) of an electrically driven vehicle, comprising - a battery monitoring device ( 3 ) for detecting at least two different ones with the battery ( 2 ) associated current output values (I _D , I _S ), - a measuring device ( 4 ) for measuring the battery ( 2 ) output current (I _actual ), - a computing unit ( 8th ) connected to the measuring device ( 4 ) and by means of which from the temporal evolution of the current difference (I _actual - I _D ) between the current of the battery ( 2 ) output current (I _actual ) and with the battery ( 2 ) associated with the first current output value (I _D ) a charge value (Q) is calculable, and - a control unit ( 7 ) connected to the battery monitoring device ( 3 ) and the arithmetic unit ( 8th ) by means of which, depending on the temporal evolution of the battery ( 2 ) current (I _actual ) the maximum of the battery ( 2 ) Deliverable current (I _max) is predetermined, - wherein, if the calculated amount of charge (Q) is less than or equal to a set charge limit value (Q _Gr), the maximum (from the battery 2 ) deliverable current (I _Max ) by means of the control unit ( 7 ) same as with the battery ( 2 ) Associated second current output value (I _S) can be placed, and - wherein, if the calculated amount of charge Q) is greater than the predetermined charge limit value (Q _Gr) (corresponding to a maximum (of the battery 2 ) deliverable current (I _Max ) by means of the control unit ( 7 ) as a function of the calculated charge value (Q) smaller than that with the battery ( 2 ) associated second current output value (I _S ) can be set.

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