Method for rapidly charging an electric energy storage device of an electrically driven vehicle

Abstract

The present invention relates to a method, a device, an energy accumulator, and a charging device for performing a rapid charging process on an electric energy accumulator (40) of an electrically driven vehicle, wherein the energy accumulator (40) comprises: a housing (41), a first combination of module strings (42) that can be charged simultaneously, a second combination of module strings (44) that is non-intersecting with the first combination of module strings (42) and can be charged simultaneously, and a first external terminal (46) for receiving electrical energy, wherein the first combination of module strings (42) and the second combination of module strings (44) are in a structural unit, and wherein the method comprises: sequentially and / or partially alternatingly charging the first combination of module strings (42) and the second combination of module strings (44) in accordance with a predefined charging strategy.

Description

Technical Field

[0001] The invention relates to a method for carrying out a rapid charging process of an electrical energy storage device of an electrically driven vehicle. In particular, the invention relates to a rapid charging process for a mean temperature battery. Background Art

[0002] In electrically driven vehicles, such as electric and hybrid vehicles, and in stationary applications, rechargeable traction batteries based on lithium are used to supply electrical energy to the electric drive device. The corresponding battery pack can be constructed, for example, from a plurality of battery modules connected in series, wherein each battery module can have a plurality of battery cells connected in series or in parallel. The battery systems currently used in vehicles must also be available at any time under low temperatures. This applies not only to the charging process, but also to the discharge process. The new technology of lithium batteries consists of solid electrolytes because they generally have a higher energy density. Its chemical components are highly active and only operate within a certain temperature range, for example, above 50°C and below 90°C. Outside the temperature range, they are limited in their power behavior due to high internal resistance, or are not allowed to operate for safety reasons.

[0003] Intelligent charging strategies are necessary, in particular, for such batteries, so that they can be charged as quickly as possible within a narrow, predefined temperature range. Charging processes of average-temperature batteries or operational average-temperature batteries, whose temperature lies within the predefined temperature range, can lead to excessive temperatures of the battery cells, in particular during rapid charging. This problem is countered by appropriate cooling, since precisely charging processes with high currents lead to additional heating of the cells, as a result of which the temperature of the battery further increases.

[0004] US 953203 B2 describes a secondary battery system, which consists of a plurality of secondary battery packs, which are charged alternately and repeatedly in accordance with a predefined sequence by means of a control circuit, wherein only one secondary battery pack is in a charging state, and the other secondary battery packs are not charged during this time period. After a predefined charging time, the control circuit selects the corresponding next secondary battery pack based on a predefined sequence for the charging process. This sequence is repeated cyclically until the secondary battery system has reached its target charge state.

[0005] DE 102010043912 A1 describes a method for determining the state of charge of cells of a battery pack, a battery pack having a module for determining the state of charge of cells of a battery pack, and a motor vehicle having a corresponding battery pack, which can be used in particular for accelerated battery compensation in the case of a battery pack having a plurality of electrochemical cells, such as in the case of a traction battery of a motor vehicle. Summary of the invention

[0006] The subject matter of the invention is a charging strategy for an operational mean-temperature battery which can be charged in a rapid charging method without reaching the temperature limits of its operating temperature range and in which relaxation is also taken into account almost completely.

[0007] According to a first aspect of the invention, a method for performing a rapid charging process on an electrical energy storage device of an electrically driven vehicle is proposed. In this context, a rapid charging process means, in particular, a complete charging process, which comprises: connecting a charging device to the energy storage device, charging the energy storage device and, after the rapid charging process, disconnecting the charging device from the energy storage device. The energy storage device can be, in particular, a mean temperature battery, the operating temperature range of which is, for example, between 50° C. and 90° C., in particular between 70° C. and 90° C., the energy storage device comprising: a first combination of simultaneously chargeable module strings and a second combination of simultaneously chargeable module strings that are disjoint with the first combination of module strings, wherein the first combination of module strings and the second combination of module strings are in a structural unit. The module strings can each consist of a plurality of battery modules connected in series and have corresponding contact possibilities so that the modules connected in series in the respective module string can be charged or discharged as a whole. For this purpose, the module strings themselves can each be surrounded by their own housing, wherein corresponding contact devices can be arranged on the outside of the respective housing. By means of these contact devices, the individual module strings of the energy storage device can be connected in a suitable manner.

[0008] From the point of view of optimal removal of thermal energy from the energy storage device to the surroundings of the energy storage device, it is preferably considered that the modules are suitably connected to form respective module strings. In other words, by determining the first combination of module strings and the second combination of module strings, it can be ensured that the heat generated in the respective module string during the charging process can be removed as uniformly and as quickly as possible from the energy storage housing to the surroundings. To achieve this, the module strings in the energy storage housing can be arranged parallel to one another, for example, so that preferably at least one first surface and at least one second surface of the module string respectively face the first surface of the energy storage housing and the second surface of the energy storage housing and can thus be thermally coupled in a suitable manner.

[0009] As described above, the method according to the invention provides for dividing a plurality of module strings of an energy storage device into a first combination of module strings and a second combination of module strings that is non-intersecting with the first combination of module strings, wherein this division can also be understood as a masking of a plurality of module strings, whereby the first combination of module strings is equivalent to the first mask and the second combination of module strings is equivalent to the second mask. In this regard, not only the method but also the construction of the energy storage device is not limited to the number of two combinations of module strings. On the contrary, in principle, any number of non-intersecting combinations of module strings can be envisaged as long as the number of combinations of module strings and the manner and method of dividing the module strings into the corresponding combinations of module strings implement or support the method of the invention. Taking into account suitable measures for achieving sufficient thermal coupling to the housing, a plurality of module strings can be preferably arranged parallel to each other in the housing of the energy storage device. More preferably, the selection of the first combination of module strings and the second combination of module strings can be configured so that the corresponding combinations of module strings are arranged in an interlaced and nested manner. In other words, a first combination of module strings can include all those module strings that correspond to the odd order of the arrangement when considering the parallel arrangement, while a second combination of module strings can include all those module strings that correspond to the even order of the arrangement. The physical or electrical allocation of module strings that are nested or snapped together in this way can be carried out, for example, by means of a correspondingly selected fixed wiring of the module strings.

[0010] The method according to the invention provides in a method step that, in accordance with a predefined charging strategy, a first combination of the module string and a second combination of the module string are charged in a sequentially alternating and / or partially alternating manner. The predefined charging strategy can be implemented, for example, by means of a device according to the invention comprising an analysis unit, which is configured to connect the first and second combinations of the module string to a charging device as an energy source during the charging process according to the charging strategy. The connection of the respective combination of the module string to the charging device can be carried out by means of an electrical switching unit, which can be operated by the analysis unit and can, for example, include contactors and / or relays for establishing the respective connection. The device can be a component of the energy storage device itself and can be arranged inside or outside the energy storage device housing. The analysis unit can be configured, for example, as an application specific integrated circuit (ASIC), a field programmable logic gate circuit (FPGA), a processor, a digital signal processor, a microcontroller, an analog circuit, etc. and can be connected to a memory unit in terms of information technology. In the case where the analysis unit is, for example, a microcontroller or other technical device for executing a computer program, the charging strategy can be implemented, for example, in the form of an algorithm configured as a computer program, which can be executed by the analysis unit. Alternatively, the algorithm for executing the charging strategy may also be a component of an existing battery management system and executed thereby.

[0011] The process of sequentially alternating and / or partially alternating charging of the first and second combinations of the module string is to be understood as follows, "sequentially" means that the charging phases and the charging interruption phases of the respective combination of the module string are continuously changed in succession until the entire rapid charging process is completed. The respective durations of the charging phases and the charging interruption phases can be stored, for example, in the form of predefined values ​​in a memory unit connected to the evaluation unit and read out and processed by a computer program executed on the evaluation unit during the implementation of the charging strategy. The duration of the charging phase can be varied, for example, in the range of 20 s to 500 s and in particular in the range of 30 s to 400 s, but is not limited to this exemplary range description. Depending on the boundary conditions and / or charging strategy described below, the charging duration can also exceed the exemplary range described downward and / or upward. In addition, the duration of the charging phase can be adapted during the charging phase. The duration of the charging interruption phase can be varied, for example, in the range of 120 s to 180 s, but is also not limited to this exemplary range description. Depending on the boundary conditions and / or charging strategies described below, the charging duration may also, for example, significantly exceed the range described by way of example both downwardly and upwardly. In addition, the duration of the charging phases may be adapted during the charging process.

[0012] The terms "alternatingly" and "partially alternatingly" are associated with the above-described sequential charging process of alternating charging of a first combination of module strings and a second combination of module strings. In other words, the starting times of the repeated charging phases of the first and second combination of module strings can be selected in such a way that the corresponding charging phases do not overlap or only partially overlap. That is to say, for example, while the first combination of module strings is in the current charging phase, the second combination of module strings can preferably be in a charging interruption phase. This does not exclude that, depending on the charging strategy, it may make sense to charge the two combinations of module strings simultaneously for a certain period of time or to charge them with partial overlap over the entire charging process. Simultaneous charging can be particularly advantageous when the temperature of the energy storage device is below the required operating temperature range at the beginning of the charging process (for example, below approximately 50° C. in the case of an average temperature battery pack). In this case, it may make sense to charge the two combinations of module strings simultaneously for a certain period of time until the energy storage device is discharged due to the heat release caused by the charging process. And as a whole (gesamthaft) is within the required operating temperature range. In the opposite case, in which the temperature of the two combinations of module strings is within the upper limit range or above its permissible operating temperature at the beginning of the rapid charging process, it can also be advantageous if the charging strategy in this case first provides for a common charging interruption phase before implementing the respective first charging phase of the two combinations of module strings. In such an initial charging interruption phase, the two combinations of module strings can therefore first be cooled to a temperature suitable for the rapid charging process. Accordingly, many other variants of the charging strategy with regard to the sequence of the charging phases and the charging interruption phases of the respective combinations of module strings can be conceived in order to achieve the tasks and advantages according to the invention.

[0013] The purpose of the alternating and / or partially alternating charging is to avoid excessive heat release during the charging process, as usually occurs in connection with a rapid charging process of the energy storage device. By always charging only a part of the multiple module strings of the energy storage device at the same time with the method according to the invention, while the other parts of the multiple module strings are in a charging interruption phase, the heat energy generated by the charging process that must be discharged to the outside in order to comply with the operating temperature range of the energy storage device is correspondingly less. For this reason, the (active) cooling of the energy storage device during the charging process can be omitted or at least significantly reduced by the method according to the invention, which can lead to cost savings in particular due to unnecessary cooling or cooling that is only required to a small extent. Another advantage of the method according to the invention in connection with the sequential alternating and / or partially alternating charging is that the corresponding charging interruption phase for preventing excessive heat release in the energy storage device can be used at the same time as a relaxation phase for the corresponding combination of the module strings. The regular relaxation possibility of the module strings ensured in this way prevents a voltage drop (Spannungseinbruch) of the energy storage device caused by relaxation at the end of the charging process, while at the same time due to the repeated relaxation phases a higher energy can be introduced into the energy storage device.

[0014] The following description shows preferred embodiments of the invention.

[0015] In another advantageous embodiment of the invention, the method according to the invention further comprises the following steps: determining first state information of a first combination of a module string and determining second state information of a second combination of a module string. The first and second state information may include, for example, temperature, state of charge, voltage, state of health, etc. and may be detected by means of sensor means (Sensorik) known in the prior art for battery modules. The sensor means may be connected to the analysis unit in information technology via a data input of the analysis unit according to the invention, so that a signal provided by the sensor means may be received by the analysis unit, wherein the signal represents the state information of the module string. Based on the state information, the analysis unit may adapt during the charging process and / or initially select the charging strategy implemented by it before the start of the charging process. For example, due to an excessively high ambient temperature of the energy storage device, it may be necessary to adapt the charging strategy during the charging process, because in this case, the heat energy generated by the charging process may not be discharged to the surrounding environment to a sufficient extent. With regard to the charging strategy, the analysis unit may respond thereto, for example, to cause a prolongation of the charging interruption phase during the charging process of the corresponding combination of the module string.

[0016] Furthermore, the charging current for the first combination of module strings and the second combination of module strings is constant or is adapted according to a predefined charging strategy. If the battery pack overheats at the beginning of charging due to self-heating and / or high ambient temperature, it may be advantageous, for example, to adapt the charging current during the charging process in order to charge directly with a maximum current suitable for a fast charging process. In such a case, the charging strategy may be adapted, for example, such that the charging process first starts with a lower charging current and increases during the charging process in response to a subsequent cooling of the energy storage device based on the lower charging current in combination with a suitable charging interruption phase. The adaptation of the charging current can also be carried out as a function of further status information and is not limited to temperature dependence.

[0017] In addition, instead of the fixed wiring described above, the module strings can be variably determined for the first combination of module strings and the second combination of module strings by means of a controllable electrical switch matrix. The switch matrix can be connected to the data input of the analysis unit in terms of information technology, just like the switch unit described above. The switch matrix is ​​preferably set up in such a way that any combination of module strings can be wired in the switch matrix by the analysis unit by means of the control of the switch unit. In this regard, it can be advantageous that not only the number of different combinations of module strings but also the selection of the corresponding module string for the corresponding combination of module strings is performed according to the charging strategy and / or the status information of the corresponding module string received by the analysis unit. This process can preferably be carried out before the start of the charging process so that, for example, the uneven temperature distribution present in the energy storage device at the start of charging can be taken into account.

[0018] Additionally, the duration of the charging phase and / or the duration of the charging interruption phase for the first combination of module strings and for the second combination of module strings can be selected as a function of the relaxation phase and / or as a function of the current temperature of the respective combination of module strings.

[0019] In a further advantageous embodiment of the invention, the first combination of module strings and the second combination of module strings are charged simultaneously in the end phase of the charging process during a predefined duration of the end phase. In this way, it is ensured that the first and second combinations of module strings have the same charge state before the end of the rapid charging process, so that they can be connected without problems for the subsequent energy receiving phase of the charging process based on their same charge state. For example, the start time of the end phase of the rapid charging process can be determined as a function of the target charge state of the energy storage device, in that the end phase is started at a current charge state determined by the evaluation unit, which is, for example, 5% below the target charge state.

[0020] According to a second aspect of the present invention, a device for performing a rapid charging process on an electric energy storage device of an electrically driven vehicle is proposed, and the device may include an analysis unit. The analysis unit may be configured, for example, as an ASIC, an FPGA, a processor, a digital signal processor, a microcontroller, an analog circuit, etc. and may be connected to a memory unit in terms of information technology. In addition, the analysis unit is configured in combination with a data output end to perform sequential alternating and / or partially alternating charging of a first combination of a module string that can be charged simultaneously and a second combination of a module string that can be charged simultaneously in accordance with a predefined charging strategy. For example, it can be done in such a way that the analysis unit controls the switching unit according to the charging strategy by means of an information technology connection to the switching unit. The switching unit is again configured to discharge the electrical energy supplied to the input of the switching unit to the first combination of the module string and the second combination of the module string connected to the switching unit in accordance with the charging strategy, for performing a charging process.

[0021] In another advantageous embodiment of the device according to the invention, the evaluation unit can additionally have a data input which is connected to a sensor system in terms of information technology, which can detect status information of the first and second combination of the module string. Such status information can include, for example, the temperature, charge state, voltage and health state of the respective combination of the module string. On the basis of this status information, the computer program executed by the evaluation unit can implement a corresponding logic for selecting and / or adapting the charging strategy.

[0022] Furthermore, an energy storage device is proposed, which includes the device according to the invention. In addition, the energy storage device includes a housing, a sensor device, a first combination of module strings, a second combination of module strings, and a first external terminal for receiving or emitting electrical energy, wherein the device is configured to connect the first external terminal to the first combination of module strings and the second combination of module strings sequentially and / or partially alternately during a charging process in accordance with a charging strategy. In order to receive electrical energy during the charging process, for example, a charging device can be connected to the first external terminal via a corresponding charging cable in order to provide electrical energy.

[0023] In addition, a charging device is proposed, which includes the device according to the invention. In addition, the charging device includes a housing, an electrical energy source, a third external terminal and a fourth external terminal, wherein the third external terminal is configured to be connected to a first combination of module strings via a first external terminal of the energy storage device for receiving or emitting electrical energy, and wherein the fourth external terminal is configured to be connected to a second combination of module strings via a second external terminal of the energy storage device for receiving or emitting electrical energy, wherein the device is configured to connect the electrical energy source to the first combination of module strings that can be charged simultaneously and the second combination of module strings that can be charged simultaneously sequentially and / or partially alternately via the third external terminal and the fourth external terminal in accordance with the charging strategy. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0025] Figure 1 shows a flow chart illustrating the steps of an embodiment of a method according to the invention;

[0026] Figure 2 A schematic overview diagram showing a first combination of module strings and a second combination of module strings for an electrical energy storage device;

[0027] Figure 3 A schematic overview of the components of the device according to the invention in combination with an energy accumulator is shown;

[0028] Figure 4 A schematic overview of the components of the device according to the invention in combination with a charging device is shown;

[0029] Figure 5a A first example of a sequentially alternating and / or partially alternating charging strategy is shown;

[0030] Figure 5b A second example of a charging strategy showing sequential alternation and / or partial alternation; and

[0031] Figure 5c A third example of a sequentially alternating and / or partially alternating charging strategy is shown. DETAILED DESCRIPTION

[0032] Figure 1A flow chart is shown, which illustrates the steps of an exemplary embodiment of a method according to the invention for carrying out a rapid charging process for an electrical energy storage device 40 of an electrically driven vehicle, wherein the energy storage device 40 comprises: a housing 41; a first group 42 of simultaneously chargeable module strings 30; a second group 44 of simultaneously chargeable module strings 30 which is non-intersecting with the first group 42 of module strings 30; a first external terminal 46 for receiving (entering) electrical energy; a sensor device 50 for detecting state information of the respective module string 30; a switching unit 60 and a device for carrying out a rapid charging process. The device comprises: an analysis unit 10, a data input 12 and a data output 14. The microcontroller-based analysis unit 10 is configured to implement a charging strategy by means of a computer program executed by the microcontroller and to actuate the switching unit 60 via the data output 14 in accordance with the charging strategy. In addition, the analysis unit 10 is connected to the sensor device 50 in an information technology manner by means of the data input 12. In a first step 100 of the method according to the invention, state information of a first combination 42 of a module string 30 is determined with the aid of a sensor system 50 in that the analysis unit 10 analyzes the signals received from the sensor system 50 via the data input 12. In this way, the analysis unit 10 determines, in particular, state information about the current temperature, the current state of charge, the current voltage and the current state of health of the first combination 42 of the module string 30. The determined state information is stored in a memory unit 20 connected to the analysis unit 10. In a second step 200 of the method according to the invention, state information of a second combination 44 of the module string 30 is determined and stored in the memory unit 20 in a manner similar to that in the first step 100. In a third step 300, the charging strategy implemented by the analysis unit 10 is adapted as a function of the first state information and the second state information. For this purpose, a predefined parameter set is stored in the memory unit 20. The parameter sets each represent predefined values ​​for implementing a plurality of predefined charging strategies. The computer program executed by the analysis unit 10 is configured to read out a parameter set suitable for the currently desired charging strategy from the memory unit 20 according to the first and second state information and use it for the charging strategy. In a fourth step 400, the analysis unit 10 controls the switch unit 60 via the data output 14 according to the current charging strategy. The switch unit 60 is configured to receive electrical energy via the first external terminal 46 and to emit the electrical energy to the first combination 42 of the module string 30 and the second combination 44 of the module string 30 according to the charging strategy according to the control signal received by the analysis unit 10. In this way, the first combination 42 of the module string 30 and the second combination 44 of the module string 30 are charged sequentially and / or partially alternately by the analysis unit 10.

[0033] Figure 2A schematic overview of a first combination 42 of module strings 30 and a second combination 44 of module strings 30 of an electrical energy storage device 40 is shown. The module strings 30 each consist of a plurality of modules 32 connected in series and are arranged parallel to one another in the energy storage device 40. With the aid of fixed wiring, for the first combination 42 of module strings 30, those module strings 30 are each electrically connected to one another in the form of a parallel circuit, which corresponds to an odd ordinal number with respect to the parallel arrangement of the module strings 30. Similarly, with the aid of fixed wiring, for the second combination 44 of module strings 30, those module strings 30 are each electrically connected to one another in the form of a parallel circuit, which corresponds to an even ordinal number with respect to the parallel arrangement of the module strings 30. In this way, it is achieved that the first combination 42 of module strings 30 and the second combination 44 of module strings 30 are each arranged in a staggered and nested manner.

[0034] Figure 3A schematic overview of the components of the device according to the invention in combination with an energy storage device 40 is shown. The energy storage device 40 comprises a first combination 42 of simultaneously chargeable module strings 30 and a second combination 44 of simultaneously chargeable module strings 30 in a housing 41, wherein the first combination 42 and the second combination 44 are each realized by means of fixed wiring of the respective module string 30. In addition, the energy storage device 40 has an analysis unit 10 according to the invention, which is realized based on a microcontroller. The analysis unit 10 is connected to the memory unit 20 and also has a data input 12 and a data output 14. By means of the data input 12, the analysis unit 10 is connected to the sensor system 50 of the energy storage device 40 in terms of information technology. The analysis unit 10 receives sensor signals from the sensor system, which respectively include status information about the temperature, charge state, voltage and health state of the first combination 42 of the module string 30 and the second combination 44 of the module string 30. The evaluation unit 10 is connected to the switching unit 60 of the energy storage device 40 in terms of information technology via the data output 40 and is configured to control the switching unit 60 in accordance with the charging strategy. The switching unit 60 is configured to receive electrical energy for charging the first group 42 of the module string 30 and the second group 44 of the module string 30 via the input of the switching unit 60 via a first external terminal 46 arranged on the housing 41 of the energy storage device 40. The electrical energy is provided by a charging device 70, which has a third external terminal 72, which is connected to the first external terminal 46 of the energy storage device 40 for transmitting electrical energy. In addition, the switching unit 60 has a plurality of switching contactors (not shown) which are configured to selectively emit the electrical energy received via the input of the switching unit to the first group 42 of the module string 30 and the second group 44 of the module string 30 connected to the output of the switching unit, depending on the current control of the switching unit 60 or the control of the switching contactors contained therein by the evaluation unit 10. In this way, the first combination 42 of the module strings 30 and the second combination 44 of the module strings 30 may be charged sequentially and / or partially alternately in accordance with the charging strategy.

[0035] Figure 4 A schematic overview of the components of the device according to the invention is shown in combination with a charging device 70, which is arranged in a housing 71. Figure 3 In order to avoid redundant description, only the differences in terms of component arrangement and the differences with Figure 3 different components. In other cases, Figure 3 The functionality and characteristics of the corresponding components described in Figure 4 Applicable in the context of. Figure 3 The implementation method and Figure 4The main difference between the embodiments in the embodiment in the embodiment is that the device according to the invention, including the evaluation unit 10 for implementing the charging strategy, is not a component of the energy storage device 40 itself, but a component of the charging device 70. This also applies to the switching unit 60, which is connected to the electrical energy source 76 in the charging device 70 in order to receive the electrical energy emitted by the energy source 76 via the input of the switching unit 60. The output of the switching unit 60 is connected to a third external terminal 72 and a fourth external terminal 74 arranged on the housing 71 of the charging device 70 in the present embodiment.

[0036] In the present embodiment, the energy storage device 40 comprises only a first combination 42 of module strings 30 and a second combination 44 of module strings 30, as well as a first external terminal 46 and a second external terminal 48, which are respectively connected to the combinations 42 and 44 of module strings 30. The first external terminal 46 and the second external terminal 48 are respectively connected to the third external terminal 72 and the fourth external terminal 74 by means of electrical lines (e.g., charging cables). In this way, the combinations 42 and 44 of module strings 30 can receive electrical energy from the energy source 76 that can be selectively switched by the analysis unit 10 and the switching unit 60 in accordance with the charging strategy. Another Figure 3 The difference from the embodiment in is that the sensor device 50 is connected to the data input 12 of the evaluation unit 10. Since the evaluation unit 10 is now a component of the charging device 70, the charging device 70 has a second sensor terminal 54, which is arranged on the housing 71 of the charging device 70. In addition, the energy storage device 40 has a first sensor terminal 52, which is arranged in the housing 71 of the energy storage device 40. The first sensor terminal 52 and the second sensor terminal 54 are connected by means of an electrical line (for example, a charging cable) so that the sensor signal of the sensor device 50 can be transmitted from the energy storage device 40 to the evaluation unit 10 according to the invention in the charging device 70.

[0037] Figure 5a A first example of a sequentially alternating and / or partially alternating charging strategy is shown. It can be seen that the charging process 86 for the first combination 42 of the module string 30 and the charging process 88 for the second combination 44 of the module string 30 controlled by the evaluation unit 10 according to the invention firstly provide for a simultaneous charging phase 82 (area shown in dark colors) of the two combinations 42, 44 of the module string 30 along the time axis t, in order, for example, to preheat the module to such an extent by means of the charging phase 82. The two combinations 42, 44 of the module string 30 are arranged so that they are within the desired operating temperature range. Next, first for the first combination 42 of the module string 30, a charging interruption phase 84 (lightly colored area) follows, so that the temperature of the first combination 42 of the module string 30 can drop during the charging interruption phase 84 and relaxation can occur simultaneously in the respective module string 30. Then, the charging phase 82 of the first combination 42 of the module string 30 occurs again, and the analysis unit 10 causes a charging interruption 84 for the second combination 44 of the module string 30 during this time period. Thereafter, the alternating charging shown here by way of example continues sequentially until a predefined end phase of the entire fast charging process is reached. From the time the predefined end phase is reached, the two combinations 42, 44 of the module string 30 are charged together until the final completion of the fast charging process.

[0038] Figure 5b A second example of a sequentially alternating and / or partially alternating charging strategy is shown, which is similar to Figure 5a The example in FIG. 1 differs in that a charging process 86 for a first combination 42 of module strings 30 and a charging process 88 for a second combination 44 of module strings 30 initially provide for a longer simultaneous charging phase 82 , and that the interruption of charging of the first combination 42 of module strings 30 and the interruption of charging of the second combination 44 of module strings 30 do not directly follow one another.

[0039] Figure 5c A third example of a sequentially alternating and / or partially alternating charging strategy is shown. Figure 5a and 5b The difference is that the charging process 86 for the first combination 42 of the module string 30 first provides for a charging phase 82 and the charging process 88 for the second combination 44 first provides for a charging interruption phase 84. This is followed by an alternating sequence of charging phases 82 and charging interruption phases 84 between the two combinations 42, 44 of the module string. At a predefined time at the end of the rapid charging process, the two combinations 42, 44 of the module string are charged again simultaneously.

Claims

1. A method for carrying out a rapid charging process of an electrical energy storage device (40) of an electrically driven vehicle, The energy storage device (40) is a mean temperature battery pack and comprises: Housing (41), A first combination (42) consisting of a plurality of module strings (30) capable of being charged simultaneously, a second group (44) consisting of a plurality of the simultaneously chargeable module strings (30) which is disjoint from the first group (42) consisting of a plurality of module strings (30), and a first external terminal (46) for receiving electrical energy, wherein the first combination (42) of the module string (30) and the second combination (44) of the module string (30) are in a structural unit, and The method comprises: sequentially and alternately charging (400) the first combination (42) of the module string (30) and the second combination (44) of the module string (30) in accordance with a predefined charging strategy, and / or partially and alternately charging the first combination (42) of the module string (30) and the second combination (44) of the module string (30) in accordance with a predefined charging strategy, wherein the module string (30) is arranged in parallel and / or the first combination (42) of the module string (30) and the second combination (44) of the module string (30) are arranged in an interlaced and nested manner.

2. The method according to claim 1, further comprising: determining (100) first state information of the first combination (42) of the module string (30) by means of a sensor system (50), By means of the sensor system (50), second state information of the second combination (44) of the module string (30) is determined (200), and based on the first state information and the second state information The charging strategy is adapted (300).

3. The method according to claim 1 or 2, wherein: The charging current for the first combination (42) of the module strings (30) and the second combination (44) of the module strings (30) is constant or adapted according to the predefined charging strategy.

4. A method according to claim 1 or 2, wherein for the first combination (42) of the module string (30) and the second combination (44) of the module string (30), the module string (30) is determined by means of fixed wiring or is variably determined by means of a controllable electrical switch matrix.

5. The method according to claim 1 or 2, wherein the duration of the charging phase (82) and / or the duration of the charging interruption phase (84) for the first combination (42) of the module strings (30) and for the second combination (44) of the module strings (30) is selected as a function of a relaxation phase and / or as a function of the current temperature of the respective combination of the module strings (30).

6. The method according to claim 1 or 2, wherein the first combination (42) of the module string (30) and the second combination (44) of the module string (30) are charged simultaneously in an end phase of the charging process during a predefined duration of the end phase.

7. A device for carrying out a rapid charging process of an electrical energy storage device (40) of an electrically driven vehicle according to a method according to any one of claims 1 to 6, the device comprising: Analysis unit (10), and Data output terminal (14), wherein The analysis unit (10) is designed in conjunction with the data output (14) to perform sequentially alternating and / or partially alternating charging of a first group (42) of a plurality of module strings (30) that can be charged simultaneously and a second group (44) of a plurality of module strings (30) that can be charged simultaneously of the electrical energy storage device (40) in accordance with a predefined charging strategy.

8. The device according to claim 7, further comprising a data input terminal (12), wherein the analysis unit (10) is further configured to: In combination with the data input terminal (12) determining first state information of the first combination (42) of the plurality of simultaneously chargeable module strings (30) of the energy storage device (40), determining second status information of the second combination (44) of the plurality of simultaneously chargeable module strings (30) of the energy storage device (40), and The charging strategy is adapted according to the first state information and the second state information.

9. Energy accumulator comprising a device according to claim 7 or 8, and a first combination (42) of a plurality of module strings (30), a second group (44) of a plurality of module strings (30), and a first external terminal (46) for receiving or emitting electrical energy, The device is designed to connect the first external terminal (46) to the first combination (42) of the module string (30) and the second combination (44) of the module string (30) sequentially and / or partially alternately during a charging process in accordance with a charging strategy.

10. A charging device comprising the apparatus according to claim 7 or 8, and Electrical energy (76), a third external terminal (72) configured to be connected to a first group (42) of a plurality of module strings (30) via a first external terminal (46) of the energy storage device (40) for receiving or emitting electrical energy, and A fourth external terminal (74) is configured to be connected to a second group (44) of a plurality of module strings (30) via a second external terminal of the energy storage device (40) for receiving or emitting electrical energy, wherein the device is configured to: In accordance with the charging strategy, the electrical energy source (76) is connected to the first combination (42) of simultaneously chargeable module strings (30) and the second combination (44) of simultaneously chargeable module strings (30) in sequence and alternately and / or partially alternately via the third external terminal (72) and the fourth external terminal (74).

Images