Control procedure for a battery system

Abstract

The present invention relates to a control method for a battery system designed for use in an electric vehicle. In order to improve a control method for battery systems in such a way that it allows changes in a current pulse concept to adapt to the respective elementary storage cells used, it is proposed that variable setting options be used in the control method for implementing a current pulse concept to represent a respective battery system as well as the cell types, designs and cell chemistries provided therein.

Description

[0001] The present invention relates to a control method for a battery system, in particular a battery system for use in an electric vehicle.

[0002] It is known from the prior art that, particularly for use in electric vehicles, a battery system is provided that is constructed from a plurality of elementary storage cells that are permanently connected to one another in series and / or parallel to achieve predetermined electrical connection properties defined by an operating voltage and a maximum current. Currently, there are very different cell types for such elementary storage cells, each with different structures and different cell chemistries, each of which exhibits very different behaviors from a technical perspective. Depending on the manufacturer, design, cell chemistry, cell type, and use in a particular application, there are correspondingly different concepts for setting a permissible current of a battery system in the charging and / or discharging direction.So-called current pulse concepts are a good way to allow higher currents in a battery system for a short time in both operating directions. This enables higher performance of the battery system in question. However, different current pulse concepts exist depending on the cell type, cell chemistry, cell manufacturer, and use in a specific application. Replacing individual components usually results in changes to the current pulse concept in question. This requires the development of a new current pulse concept, or at least modifications to an existing current pulse concept.

[0003] The present invention has the object of improving a control method for battery systems in such a way that it allows significantly easier changes in a current pulse concept in adaptation to the elementary storage cells used in each case.

[0004] This object is achieved according to the invention by the features of claim 1 in that, in the control method with implementation of a current pulse concept, a respective battery system with the cell types, designs, and cell chemistry provided therein is variably adjusted. Thus, variable adjustment options are used to represent a respective battery system as well as the types, designs, and / or cell chemistry of the elementary storage cells used. Accordingly, according to the invention, different characteristics of cell types and cell chemistry of a battery system can be variably represented by adjustment options in the control method for a current pulse concept. Thus, even without extensive adaptation work or even a completely new development of a control method, it is advantageously possible - to use a current pulse concept for many different cells and battery systems; - to take into account the peculiarities of different cells through the setting options of the concept; - to reliably comply with limitations of a manufacturer, especially with regard to a maximum current flow through the control process and - to achieve maximum performance of the battery system in question, taking into account all manufacturer specifications for the elementary storage cells used.

[0005] Advantageous further developments are the subject of the dependent claims. Accordingly, individual characteristics of the current pulse concept and dependencies are used in the algorithm in a parameterized manner. Individual characteristics of the current pulse concept and dependencies on a specific application are thus mapped using various defined parameters, as explained in more detail below.

[0006] Accordingly, in a preferred embodiment of the invention, different pulse lengths of current pulses of different magnitudes are parameterized. For example, short, but high current pulses are distinguished from shorter, longer-lasting current pulses. This distinction is made in the charging and discharging directions. This will also be discussed in more detail below using exemplary embodiments of the invention.

[0007] Furthermore, the corresponding current pulse characteristic maps are mapped to a database based on an operating temperature and a state of charge (SOC). This database, linked to the algorithm of the control method, is accessed in a method according to the invention.

[0008] In a further development of the invention, a waiting or rest period required after each current pulse is stored in the database. This waiting or rest period takes into account, in particular, the compensating processes in the elementary storage cells that occur after a charging or discharging pulse. Essentially, compensation for any additional heating by dissipation or cooling through cooling measures is considered in order to prevent a continually increasing heating within the battery system.

[0009] According to an essential development of the invention, a dependency on a type of current pulse is parameterized and provided with an indication, particularly in the database, as to whether different types of current pulses may be used in combination with one another.

[0010] Counters are preferably used to monitor the respective current pulses and the associated waiting times. The current pulse concept thus allows a permissible constant current after a respective pulse has been used up until the next current pulse of the same type can be applied again.

[0011] In addition, a further development in the database determines whether an interruption of a particular current pulse is permitted.

[0012] In one embodiment of the invention, a parameter is used in the database to determine as a flag whether counters for the pulses may be counted down over time. During this time, the counter in question may continue to count up due to the occurrence of corresponding pulses.

[0013] In a further development of the invention, a current flow is assigned a pulse height based on the heating of the respective battery system, depending on the direction of current flow. This allows different threshold values, maximum pulse durations, waiting times, and / or decay rates to be assigned to the respective pulse heights for each flow direction to reduce the counters.

[0014] Further features and advantages of embodiments of the invention are explained in more detail below with reference to exemplary embodiments based on the drawings. In these, the following are shown: Fig. 1: a time course of two example pulses; Fig. 2: a time course of a sequence of pulses in the discharge direction; Fig. 3: a temporal progression of a pulse with a schematic representation of a counter belonging to this pulse type; Fig. 4: a time course of a pulse with a basic representation of a counter with complete regeneration of this counter; Fig. 5: a time course of a sequence of pulses in the discharge direction using two counters and Fig. 6: a time course of a sequence of pulses in the charging and discharging direction analogous to the representation of Fig. 2.

[0015] Throughout the various illustrations of the drawing, the same reference numerals are used for identical process steps, parameters, currents, etc. Without limiting the invention, it is described below only against the background of an application in a battery management system of a battery system designed as a high-voltage system for use in electric vehicles.

[0016] Currently, control methods for operating battery systems in the charging and discharging direction are always newly developed for each respective battery system, so that such control methods usually have to be at least newly developed or at least adapted in the form of programming work when changing the elementary storage cells used in the battery system in question to another manufacturer.

[0017] In order to improve a control method for battery systems in such a way that it allows changes in a current pulse concept in adaptation to the elementary storage cells used in each case and / or a change of the manufacturer of the elementary storage cells, an embodiment of a control method is described below which is implemented with a special parameterization as software in a battery management system BMS that can be flexibly adapted to the conditions of a respective application.

[0018] A respective battery system is subsequently recorded only based on its performance data and the associated marginal ranges of permissible operation, i.e. in particular a voltage at the poles at permissible currents for a charging and discharging range over specified pulse times in an operating range defined by a minimum and a maximum operating temperature. A key starting point for a control procedure described below are cell data and specifications from each manufacturer of the elementary storage cells used in the respective application, which must be reliably adhered to in order to maintain, in particular, a manufacturer's functional guarantee over a specified lifetime of the storage cells in question. These manufacturer guarantees are generally valid until a limit of 80% residual capacity is reached or an internal resistance doubles.

[0019] In the embodiment described below, the following parameters are defined: A current flow I(t) is considered in terms of its magnitude, whereby the flow direction is differentiated as charging current or discharging current with respect to the battery system. A manufacturer of the elementary storage cells used in a battery system provides current pulse maps for three current pulses in the charging and discharging directions for predefined pulse durations t0, t1, and t2. Here, I0 represents a permissible continuous current or I ContI1 represents the current of a longer-lasting continuous pulse, and I2 represents the value of a short-lasting current pulse. In addition to I0 < I1 < I2, the pulse times t0 > t1 > t2 assigned to these currents also apply. In this exemplary embodiment, these pulse times are defined as t2 = 10 s, t1 = 30 s, and t0 = 3 min. These and other specifications from the cell manufacturer and application-specific settings are arranged in the form of a parameterization interface and stored in a database for retrieval by the control process.

[0020] Current pulse characteristics for t0=3 min are defined as constant current characteristics with I0 = I Cont used. A time t1 for the permissible duration of the long current pulse I1 is parameterized with t1=30 s. A time t2 for the permissible duration of the short current pulse I2 is parameterized with t2=10 s, as in Fig. 1. Pulses I1 and I2 represent permissible increased power outputs or power consumptions of the battery system over the respective pulse durations t1 and t2 within the framework of the control with a current pulse concept, which are beyond a permissible continuous load for improving the performance of the battery system in a charging or discharging operation, which is determined by the quantity I0 = I Cont These permissible increased pulse loads of the battery system and each of its elementary cells within the scope of a current pulse control are Fig. 1 shown as hatched areas.

[0021] The maps are parameterized with an 11 x 1 temperature vector to account for a dependence on the operating temperature ϑ. Furthermore, the maps are parameterized with an 11 x 1 SOC vector to account for a dependence on the state of charge (SOC) of the battery system. For simplification and to ensure sufficiently accurate representation, the SOC is rasterized in 10% increments from 0% to 100% charge of the battery system, resulting in a total of 11 values. For an even finer representation (not shown here), 5% increments are used, resulting in a total of 21 values.

[0022] In the present embodiment, the following current pulse characteristic maps are generated in parameterized form, each with the support points temperature ϑ and state of charge SOC: • a current pulse characteristic map in the charging direction CH for the permissible constant current I0 with the dimensions 11 x 11; • a current pulse characteristic map in the charging direction CH for the permissible current in the long current pulse I1 with the dimensions 11 x 11; • a current pulse characteristic map in the charging direction CH for the permissible current in the short current pulse I2 with the dimensions 11 x 11; • a current pulse characteristic map in the discharge direction DCh for the permissible constant current I0 is with the dimensions 11 x 11; • a current pulse characteristic map in the discharge direction DCh for the permissible current in the long current pulse I1 with the dimensions 11 x 11, • and finally a current pulse characteristic map in the discharge direction DCh for the permissible current in the short current pulse I2 with the dimensions 11 × 11.

[0023] Thus, a total of six current pulse characteristic maps are parameterized for the three predefined current intensities in the charging and discharging directions and each is provided with the support points temperature ϑ and state of charge SOC and stored in a database that only needs to be created once for the respective cell manufacturer and the cell type used.

[0024] Fig. Figure 2 shows a temporal progression of a sequence of pulses in the discharge direction of a battery system. The progression of the discharge current I over time t results in a threshold I at a time a. DCh,cont exceeded, and up to time c to a threshold I DCh1 From a point in time d, the discharge current oscillates only around the threshold I DCh,cont . This results in a permissible continuous discharge current I DCh,contIn time intervals, longer current pulses and also higher current pulses overlap, the latter between times b and c. This means that in this exemplary embodiment, different pulses can be combined or coupled with one another; a combination parameter K has therefore been set to "1". In addition, the pulses do not have to be run for a full, maximum permissible time length. A long current pulse I1 can therefore also be run over shorter time intervals than t1 = 30 s. An interruption parameter U has therefore been set to "1". In order to measure the load on the battery system by a respective continuous discharge current I that exceeds a permissible continuous discharge current I DCh,cont In order to find the pulsed current flow exceeding the threshold, a separate current threshold is introduced for each defined pulse current. If the threshold is exceeded, a counter is started which is only stopped when the threshold is exceeded, as shown below in the figure of Fig. 3 described.

[0025] The cell data and specifications of a manufacturer also contain, among other things, characteristic values ​​for current pulses and the rest or waiting times that necessarily follow the respective current pulses. For each current pulse there is therefore a corresponding rest time that depends on the actual duration of each current pulse. Normally the waiting time is at least as long as the length of the pulse, but in most cases longer. The introduced energy can either be dissipated by converting the root mean square or RMS value of the current to the permitted constant current in order to determine the time in which the current actually drawn after the current pulse corresponds to the permitted constant current. Alternatively, the energy input into the cell is examined, which leads to heating that is compensated by active cooling.In this exemplary embodiment, the following definition is made: For a current pulse of 10 s, a wait of 20 s is required until the energy introduced into a storage cell by the current pulse can be considered dissipated. For a current pulse of 20 s, for example, a wait of 40 s is required; for a current pulse of 30 s, for example, there is a waiting or rest period of 60 s before the next current pulse can be executed. This rest period R is generally independent of the type or form of the respective current pulse. It depends only on the actual current pulse duration, i.e., in this case, 10 s, 20 s, or 30 s. However, the times generally differ depending on the cell manufacturer and cell format.

[0026] For the duration of the short current pulse I2, in this example with t2=10s, a corresponding rest period R2 = 20s has been parameterized or specified. If a current pulse occurs with a duration between t2 and t1, it is treated as a so-called partial current pulse. For the duration of a partial current pulse I 21 with e.g. t 21 =20s a corresponding rest time R 21 with R 21 =40s. For the duration of the long current pulse I1, here defined as t1=30s, a corresponding rest period R1 with R1=60s is defined to ensure consistency.

[0027] A current pulse counter, or counter C(I1), is provided for the long current pulse I1. The long current pulse I1 may only be run for a maximum time of t1 = 30 s. Fig. Figure 3 shows a time course of a sequence of pulses in the discharge direction with application of the counter C(I1) over time t with a regeneration of the counter C(I1). As soon as the flowing current I is higher than the permissible continuous current I Cont is, the counter or current pulse counter C(I1) counts upwards. In a database with presets of the control procedure, a parameter R is used as a flag or switch to determine whether the counter or counter C(I1) for the pulse I1 may be counted down over time. If R is set to "1", the current pulse I1 can also be reduced again in the phase in which it is increased. If the current pulse exceeds the constant or continuous current I Cont=I0, then the counters for the current pulses are incremented as described above. If the current falls below the permissible constant current again and the counters C(I1) are above zero, then the counter values ​​are decremented again. This process is shown in the figure. Fig. 3. When reducing the counter C(I1), a relationship between the counter for the respective current pulse and a stored waiting time can be taken into account in a manner not further illustrated here. For example, if the waiting time is twice as long as the permissible pulse length, the counter for the current pulse is reduced by a factor of 0.5 during the time the current is below the constant current. This means that the counter build-up in 2 seconds requires 4 seconds to complete.

[0028] In the present embodiment, however, the rise and fall times are equal. Therefore, if the current is smaller than the continuous current I Cont=I0, the current pulse counter C(I1) counts down in the same way as it counted up previously. This results in a ramp-shaped curve.

[0029] Also Fig. Figure 4 shows a time course of a sequence of pulses in the discharge direction using the counter C(I1) over time t. The same times are used for the rise and fall of the counter, so that the counter curves here also have the same gradients for the rise and fall. If the current falls below the permissible constant current, the counter for the current pulse is counted down again. The current pulse counter value is only reduced until it reaches 0 s. A reduction is only active if the current pulse counter value is greater than 0 s. Fig. 4, the time intervals have now been selected so that regeneration of the current pulse counter C(I1) is fully completed. When the current pulse counter C(I1) reaches 0, further reduction of its value is stopped.

[0030] A hatching has been changed after the counter has decayed, since regeneration is no longer possible at that point. Thus, after the counter C(I1) has stopped increasing at time b, with the current falling below the threshold of the permissible continuous current I Cont After only 4 s at time x, the counter C(I1) is balanced. A remaining and in Fig. 4, characterized by a different filling, therefore has no further impact on the counter. The same situation occurs here after the pulse between times c and d at time y.

[0031] Furthermore, in the present exemplary embodiment, a current pulse counter or counter C(I2) is provided for the short current pulse I2. The short current pulse I2 may be run for a maximum time of t2 = 10 s. When the counters are reduced, the current pulse counter values ​​of the current pulses I1 and I2 are reduced. For the current pulse I1, the counter is reduced by the same time increment as the current pulse counter value is increased by 1 s. For the current pulse I2, the counter is reduced by a time step size that reflects the ratio between the permissible current pulse counter values ​​of I2 and I1, i.e., by 1 / 3 s in this example. Reduction and incrementation of the counters for the current pulses can be combined dynamically.

[0032] Fig. Figure 5 shows a time course of a current flow with a sequence of pulses in the discharge direction, which, compared to the example of Fig. 3 are significantly stronger and therefore requires the use of the two counters C(I1) and C(I2). Analogous to the procedure of Fig. 2 - 4, time a represents a starting point for counter C(I1), and from time b, counter C(I2) is also started. At time a, the current flow I(t) exceeds the threshold for a continuous current in the discharge direction, I cont , and only falls below this threshold again at time h. The corresponding counter C(I1) thus increases linearly up to time h. Over three time periods from time b onwards, the threshold value for a long current pulse in the discharge direction, I1, is also exceeded, with this threshold being undershot again at times c, e and g. Accordingly, the corresponding counter C(I2) shows a monotonic, terrace-like increase from time b onwards up to time h, while the counter C(I1) continues to increase linearly during these three intervals.

[0033] There is a defined time criterion for the current pulses, which is monitored by a time counter. If a time window is not fully utilized by a current pulse, the permissible current pulse time can be increased again by the counter for a remaining time. Current pulse I2 can run for up to 10 s with permissible interruptions, and current pulse I1 can also run for up to 30 s with interruptions. A combination of the two current pulses I1 and I2 is also permitted in this example. However, as soon as a permissible time for current pulse I2 has been completely used up, current pulse I2 is blocked, while current pulse I1 remains enabled. As soon as a permissible time for current pulse I1 has also been completely used up, both current pulses are blocked. At time g, the counter for current pulse I2 reaches the limit of 10 s duration, the permissible current is limited to the current of current pulse I1.A waiting period W begins for this counter. At the subsequent time h, the counter for current pulse I1 also reaches the 30 s time mark, so this pulse is blocked from this point on. A waiting period W also begins for this counter, and the permissible current is set to the constant current I. Cont Both current pulse counters are limited in the example of Fig. 5 has been fully utilized starting from the dash-dotted area. A waiting period then follows, and only then are the counters reduced again in a ramp-like manner with a respective gradient.

[0034] Furthermore, the proposed control method depends on the shape of the current pulses. Different current pulses can in principle be combined with one another within a permissible current pulse time and a permissible energy input. A combination of these results in different current pulse shapes, unless a cell manufacturer prohibits such a combination. In the cell manufacturer's specifications and settings, arranged in the form of a parameterization interface, a combination parameter K for the control method is used to set whether a combination of current pulses over the entire time t1, with t1=30s in this case, is permitted. If a combination parameter K is set to K=1, the current pulses may be combined over the entire time t1. This means that if K=1, the long current pulse I1 can be run for the time t1 and, within this time t1, the short current pulse I2 can also be run for t2, in this case 10s.However, if the combination parameter K is set to K=0, a combination of the two current pulses I2 and I1 is only permitted within the time period t2 = 10 s. As soon as the short current pulse I2 has been applied within the time t2 with K = 0, both current pulses are prohibited. Then only the constant current I0 = I remains. Cont permitted. If the combination parameter K is set to K=0, only the long current pulse I1 can be run for the entire time of t1=30s.

[0035] In a preferred embodiment of the invention, the current pulses in the charging and discharging directions are considered to be independent of each other, as shown in an embodiment in Fig. 6 graphically depicts a possible temporal current profile during the travel of an electrically powered vehicle. Individual time counters and individual consideration of the respective current pulses I1 and I2 are provided for both the discharge direction DCh and the charge direction CH. Charging and discharging currents each lead to heating in the battery system, so that in this exemplary embodiment, a distinction is only made in the amount of heat input, but not in the direction of current flow. Thus, the four counters can be configured analogously to the illustration in Fig. 5 can be combined into just two counters by simply adding them together. However, from the perspective of heating the battery system in question, only the pulse height is relevant, not the flow direction of a current pulse. In other words, there is no need to distinguish between the charging and discharging directions. Therefore, it is sufficient to update counters for the respective pulse sizes. Fig. 6 shows a time course of a current flow I(t) with a sequence of pulses, which is analogous to the representation of Fig. 2 but now run in the charging and discharging directions. The exemplary temporal pulse curve now passes through the charging and discharging ranges using different pulse heights when the respective pulses are interrupted. Thus, the coupling factor K and the interruption factor U have each been set to 1. The curve of the discharge current shown over time t produces a threshold I at a time a.DCh,cont exceeded, so that a counter for a current pulse I DCh,1 is started. At time b, the discharge current also exceeds a threshold I DCh,1 , which requires the additional start of a counter for a current pulse I DCh,2 A combination of pulses is permissible, i.e. K = 1, as can be seen between times b to c, where a long and a short pulse are combined or run together. At time c, the discharge current falls below the I DCh,1 again, so that the counter for an I DCh,2 - current pulse is stopped again. At a time d the discharge current also falls below the I DCh,cont -threshold, so that the counter for an I1 current pulse is stopped again and a rest period previously determined by the two counters is counted down. Up to a time e, the discharge current moves into a charging range and there into the charging current I, which is permissible over long periods. Ch,cont, at a time f the charging current exceeds a threshold I Ch,1 until a time g. Until a time h, the charging current drops to the charging current I permissible over long periods of time Ch,cont in order to maintain the discharge current I permissible over long periods of time until time i DCh,cont Up to a point in time j, the discharge current remains above the permissible discharge current I DCh,cont , in order to then at time k again set the threshold of the permissible charging current I Ch,cont to be exceeded until time 1. From time m to time n, the current is then again a discharge current above the threshold of the permissible discharge current I DCh,contIn the present exemplary embodiment, the respective thresholds have been chosen to be different in the charging and discharging directions of the current flow in order to reflect the influence of respective heating. Nevertheless, the same counters are used for the longer pulses and the shorter pulses in the charging and discharging directions. The current profile results in the Fig. Counter Ctrl and Ctr2 outlined in Figure 6.

[0036] Since both pulses in the discharge and charge directions are run significantly below their respective maximum durations and an interruption with U = 1 is also permissible in this embodiment, there is no enforced limitation of the respective pulses and no waiting time in this example.

[0037] If R is set to 0, then the current pulse - in contrast to the embodiment of Fig. 3 - only reset when a corresponding waiting time is reached. The waiting time counter is incremented separately here. This means there are two options for counting down the current pulse: Either the current remains below the permissible constant current for so long that the waiting time counter reaches the value for the stored waiting time, and then the current pulse counter is set to "zero," or the current pulse is incremented until the maximum permitted value for the current pulse is reached. In this case, operation of this current pulse is prohibited, and the waiting time counter must be incremented to the stored value, as shown in the figure. Fig. 6 shown.

[0038] An interruption parameter U specifies whether a current pulse must be executed in one piece or over its predetermined time duration, or whether this current pulse can be executed in several parts. If the interruption parameter U is set to 0, the current pulses must not be interrupted. If the constant current I0 is exceeded at U=0, the long current pulse I1 is activated. If the constant current I0 = I Cont If the current value is now undershot, a further current pulse is only permitted after the corresponding rest period. If the long current pulse I1 is exceeded at U=0, the short current pulse I2 becomes active, ie, C(I2) > 0. If the long current pulse I1 is now undershot, a further short current pulse I2 is only permitted after the corresponding rest period.

[0039] However, if the interruption parameter is set to U=1, then an interruption of the current pulse is permitted. This means that the current may fall below the current criterion for the current pulse, the associated counter is interrupted, and thus the value of the counter in question is maintained. Subsequently, the current may again exceed the current criterion for the current pulse, and the associated counter then continues to count. If the current pulse is interrupted at U=1, the associated counter continues to count as the waiting time counter. If the waiting time counter has Ctr w the corresponding value for the rest time R is reached, then the counters for the current pulses C(I1) and C(I2) and waiting time Ctr w reset.

[0040] Furthermore, the following regulations are implemented in the procedure: If a current pulse has been run for less than or equal to the time period t2 with t2=10s, then the rest time R is set to the value R2. This means that if no further pulse is run for the rest time R2 of e.g. 40s, then the counters for the current pulses C(I1) and C(I2) and the waiting time Ctr w set to 0.

[0041] If a current pulse is applied for less than or equal to a time period t 21 with here t 21 =20s, but more than t2 was driven, then the rest time R is set to the value R 12 This means that if the rest period R 21 from e.g. R 21 =40s no further pulse is run, then the counters for the current pulses C(I1) and C(I2) and waiting time Ctr w set to 0.

[0042] If a current pulse for less than or equal to t1 with t1=30s but more than t 21 with t 21=20s), then the rest time R is set to the value R1. This means that if no further pulse is run for the rest time R1 of e.g. R1=60s, then the counters for the current pulses C(I1) and C(I2) and the waiting time Ctr w set to 0.

[0043] As soon as the pulse counter for the long current pulse has reached C(I1) = t1 with t1=30s during a permissible interruption, i.e. U=1, a waiting time of R1 with R1=60s must be waited until the next current pulse is permitted, regardless of the previous waiting time. List of reference symbols DCh current flow towards discharging the battery system C(I1) Counter / Counter of the flow duration of long current pulse I1 C(I2) Counter / Counter of the flow duration of short current pulse I2 Ch Current flow towards charging the battery system Ctr w Waiting time counter I Cont Threshold of a constant current, I Cont= I0 I1 threshold of a long current pulse I2 threshold of a short current pulse I 21 Threshold of a partial current pulse K combination parameters as flag R Countdown parameter as flag R1 Rest time of the short current pulse I1, R1 = 80s R2 Rest time of the short current pulse I2, R2 = 40s R 21 Rest time of the partial current pulse I 21 , R 21 =60s SOC State of charge of the battery system t0 duration of the permissible continuous current I0, t0 = 3 min t1 duration of the long current pulse I1, t1 = 30 s t2 duration of the short current pulse I2, t2 = 10 s t 21 temporal length of a partial current pulse I 21 , t 21 = 20s ϑ\ Battery system temperature U Interrupt parameter as flag W Waiting time as forced rest time of a respective current pulse a,b,c,d,e,f,g,h,i,j,k,l,m,n Times of exceeding or falling below a threshold x,y times of balancing a counter

Claims

[1] Control method for a battery system which is constructed, in particular for use in electric vehicles, from a large number of elementary storage cells which are connected to one another in series and / or in parallel to achieve predetermined electrical connection properties defined by an operating voltage and a maximum current, characterized by that in the control process with implementation of a current pulse concept, a respective battery system with the cell types provided therein, their designs and their cell chemistry is variably adjusted. [2] Control method according to the preceding claim, characterized by that parameters for individual characteristics of the current pulse concept as well as dependencies on a particular application case are used in the algorithm of the control procedure. [3] Control method according to the preceding claim, characterized bythat parameters are used for different pulse lengths of different current pulses. [4] Control method according to one of the preceding claims, characterized by that current pulse characteristic maps relating to temperature (ϑ) and a state of charge (SOC) are read out from a database connected to the algorithm of the control process for each cell type used in the battery system. [5] Control method according to one of the preceding claims, characterized by that waiting or rest times are recorded by a counter (Ctr w ) can be read out and adjusted depending on a respective current pulse from the database. [6] Control method according to one of the preceding claims, characterized bythat a dependency on a type or form of a current pulse is parameterized and provided by a combination parameter (K) with an indication as to whether different types of current pulses may be used in combination with one another. [7] Control method according to one of the preceding claims, characterized by that a counter (C) is used to monitor the respective current pulses and associated waiting times, so that after utilizing a pulse, as long as a permissible constant current (I Cont ) until the next current pulse of the type in question is permitted again. [8] Control method according to one of the preceding claims, characterized by that it is specified in the database whether an interruption (U) of a respective current pulse is permitted. [9] Control method according to one of the preceding claims, characterized bythat a parameter (R) is used in the database to define as a flag whether counters for the pulses may be counted down over time. [10] Control method according to one of the preceding claims, characterized by that a current flow is assigned to a pulse height (I1, I2) with respective threshold values ​​based on heating of the battery system in question, depending on the direction of flow of the current.

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