Method for operating a battery and device

Abstract

A method for operating a battery (30) by means of a control device (23), which battery (30) is configured as a vehicle battery, has a first terminal (37), a second terminal (38) and a plurality of individual modules (31, 32, 33, 34, 35, 36), which individual modules (31, 32, 33, 34, 35, 36) each comprise an electrochemical energy storage device (321) and a circuit arrangement (319), which control device (23) is configured to enable different configurations (30.1 - 30.6) of the individual modules (31, 32, 33, 34, 35, 36) between the first terminal (37) and the second terminal (38) by controlling the circuit arrangements (319), is configured to perform at least one step for temperature control of the battery (30).

Description

[0001] The invention relates to a method for operating a battery and a device.

[0002] DE 10 2019 113 665 A1 shows a battery management system for a vehicle battery in which a discharge process and a charging process are controlled.

[0003] DE 10 2016 011 014 A1 discloses a method and battery management system for a vehicle battery, whereby temperature control is achieved by means of charging and discharging.

[0004] DE 10 2014 010 300 A1 discloses a method for heating a vehicle battery to a predetermined temperature value.

[0005] DE 10 2021 124 232 A1 discloses a method for temperature control of a vehicle battery during external charging of the vehicle battery.

[0006] EP 4 124 503 A1 discloses a control method for a vehicle with two traction batteries connected to each other via a bidirectional DC converter, the DC converter being operated depending on temperature information.

[0007] The CN 2 12 230 582 U shows a self-heating device for a battery.

[0008] The CN 1 13 733 986 A shows a self-heating device for a battery.

[0009] CN 1 15 084 722 A shows a method for controlling a battery heater.

[0010] DE 10 2021 110 667 A1 discloses a method for preconditioning a battery pack at cold ambient temperatures.

[0011] The EP 4 044 320 A1 shows a battery heating system with a temperature monitoring unit, a voltage conversion unit and a power supply unit.

[0012] DE 10 2014 110 410 A1 discloses a modular energy storage direct converter system with a control unit and at least one bridge branch comprising a plurality of modules connected in series.

[0013] DE 10 2022 209 872 A1 discloses a method for operating an on-board network which has a traction battery with at least two energy storage elements and a consumer.

[0014] It is therefore an object of the invention to provide a new method for operating a battery.

[0015] The problem is solved by the objects of the independent and subordinate claim.

[0016] A method for operating a battery by means of a control device, which battery is designed as a vehicle battery, has a first terminal, a second terminal and a plurality of individual modules, which individual modules each comprise an electrochemical energy storage device and a circuit arrangement, which control device is designed to enable different configurations of the individual modules between the first terminal and the second terminal by controlling the circuit arrangements, which different configurations differ at least partially from each other. - in the number of individual modules connected in series between the first connection and the second connection, - in the number of individual modules connected in parallel, and - in the interconnection direction of the electrochemical energy storage devices between the first terminal and the second terminal, in order to provide an output voltage resulting from the respective configuration between the first terminal and the second terminal and to enable operation of the battery as an AC voltage source, it is equipped to perform at least one of the following steps A) to D) for temperature control of the battery: A) During a first period of time, a first group of individual modules is subjected to a higher load by the control device than a second group of individual modules in order to create a different state of charge of the individual modules, and during a second period of time, which is after the first period of time, at least some of the individual modules of the first group are connected in parallel with at least some of the individual modules of the second group by the control device in order to charge the individual modules of the first group at least partially by the individual modules of the second group and thereby generate heat; B) When the main consumer is active and connected to the battery, the control unit controls the battery in such a way that some of the individual modules are not connected between the first and second terminals, in order to place a greater load on the remaining individual modules and thereby generate additional heat; C) When the main consumer connected to the battery is active, the control unit controls the battery in such a way that at least some of the individual modules have further individual modules connected in parallel in order to reduce the internal resistance of the parallel-connected individual modules relative to the internal resistance of a single individual module and thereby generate additional heat; D) An auxiliary consumer is activated by the control device, and the auxiliary consumer is supplied with electrical energy by the battery, wherein a plurality of the individual modules are connected in parallel to each other in order to cause heating of the plurality of the individual modules.

[0017] This method allows the battery to be heated independently of an additional heater. This eliminates the need for an additional external heater or allows the use of an external heater with a lower maximum heating output, thus resulting in weight savings for the vehicle.

[0018] According to a preferred embodiment, the main consumer comprises at least one first main consumer from a main consumer group consisting of: - Electric motor for vehicle propulsion, - Heating, e.g. battery heating and interior heating, - Air conditioning, and - Air conditioning compressor.

[0019] According to a preferred embodiment, the secondary consumer comprises at least one first secondary consumer from a group of secondary consumers consisting of: - Low-voltage electrical system, in particular 12 V electrical system, - Heating, e.g. for windows or side mirrors, seat heating, steering wheel heating, - Low beam headlights, - Fog lights, - Navigation device, and - Radio.

[0020] According to a preferred embodiment, the method is configured to perform at least two of steps A) to D) for temperature control of the battery.

[0021] According to a preferred embodiment, the method is configured to perform at least three of the steps A) to D) for temperature control of the battery.

[0022] According to a preferred embodiment, the method is configured to perform all steps A) to D) for temperature control of the battery. A combination of steps A) to D) or part thereof will accelerate the battery warm-up.

[0023] According to a preferred embodiment, an electric motor for a vehicle is provided as the main consumer, and - in step B), - in step C), or - In steps B) and C), the control unit limits the speed of the electric motor. Steps B) and C) put a strain on the battery, and an additionally high speed of the electric motor puts further strain on it. This can lead to damage.

[0024] A device comprises a battery and a control unit, the battery having a first terminal, a second terminal and a plurality of individual modules, each of which individual modules comprises an electrochemical energy storage device and a circuit arrangement, the control unit being configured to enable different configurations of the individual modules between the first terminal and the second terminal by controlling the circuit arrangements, and the different configurations being at least partially different from one another. - in the number of individual modules connected in series between the first connection and the second connection, - in the number of individual modules connected in parallel, and - in the interconnection direction of the electrochemical energy storage devices between the first terminal and the second terminal, in order to provide an output voltage resulting from the respective configuration between the first terminal and the second terminal and to enable the battery to be operated as an AC voltage source, and the device is designed to carry out such a procedure.

[0025] Further details and advantageous embodiments of the invention will become apparent from the exemplary embodiments described below and illustrated in the drawings, which are in no way to be understood as limiting the invention, as well as from the dependent claims. It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the present invention. It shows: Fig. 1 in schematic representation a single module of a battery, Fig. 2 in schematic representation a battery with individual modules accordingly Fig. 1, Fig. 3 different battery configurations shown schematically Fig. 2, Fig. 4. A first configuration of the battery from Fig. 3, Fig. 5 a second battery configuration of Fig. 3, and Fig. 6 a first device for operating the battery of Fig. 2.

[0026] In the following, identical or similarly functioning parts are designated with the same reference symbols and are usually described only once. The description builds upon itself across figures to avoid unnecessary repetition.

[0027] Fig. Figure 1 shows a single module 31 of a battery. The single module 31 comprises an electrochemical energy storage device 321 and a circuit arrangement 319.

[0028] The single module 31 has a connection 301, a connection 302, a connection 303 and a connection 304.

[0029] The circuit arrangement 319 has semiconductor switches 311, 312, 313, 314, 315, 316, 317, 318.

[0030] Terminal 301 is connected to line 305 via semiconductor switch 311 and to line 306 via semiconductor switch 312. Terminal 302 is connected to line 305 via semiconductor switch 313 and to line 306 via semiconductor switch 314.

[0031] The electrochemical energy storage device 321 is connected to conductor 305 and conductor 306.

[0032] Terminal 303 is connected to line 305 via semiconductor switch 315 and to line 306 via semiconductor switch 316. Terminal 304 is connected to line 305 via semiconductor switch 317 and to line 306 via semiconductor switch 318.

[0033] By appropriately controlling the circuit arrangement 319, different configurations can be created when several interconnected individual modules 31 are provided.

[0034] Fig. Figure 2 shows a battery 30 and a control unit 23.

[0035] The battery 30 has a first connection 37, a second connection 38 and, for example, three interconnected individual modules 31, 32, 33 accordingly. Fig. 1.

[0036] The control unit 23 is designed to control the circuit arrangements 319 of Fig. 1 to allow different configurations of the individual modules 31, 32, 33 between the first port 37 and the second port 38.

[0037] Terminal 37 is connected to terminals 301 and 302 (see below). Fig. 1) of the single module 31 is connected, and the terminal 38 is connected to the terminals 303, 304 (see Fig. 1) of the single module 33 connected.

[0038] For example, if all three individual modules 31, 32, 33 are connected in parallel, the voltage U_A between terminal 37 and terminal 38 corresponds approximately to the voltage of one of the individual modules 31, 32, 33.

[0039] For a parallel connection of the individual modules 31, 32, for example the semiconductor switches 315 and 318 of the individual module 31 and the semiconductor switches 311 and 314 of the individual module 32 are connected in parallel.

[0040] If, on the other hand, all three individual modules 31, 32, 33 are connected in series, the voltage U_A corresponds approximately to three times the voltage of one of the individual modules 31, 32, 33.

[0041] A series connection of all individual modules 31, 32, 33 can be achieved, for example, by switching the semiconductor switches 314 and 317 on each of the individual modules 31, 32, 33.

[0042] For a series circuit with reversed polarity at terminals 37 and 38, for example the semiconductor switches 313 and 318 can be switched to conducting on each of the individual modules 31, 32, 33.

[0043] A single module can also be removed from the circuit between terminals 37, 38 by, for example, making the semiconductor switches 314 and 318 conductive in single module 31 and connecting the single modules 31, 32 in series or parallel.

[0044] By changing the configuration of the individual modules 31, 32, 33 between the terminals 37, 38, the resulting output voltage U_A can be influenced.

[0045] The circuit arrangement 319 thus enables different configurations between several individual modules 31.

[0046] The present circuit arrangement 319 allows for a high degree of flexibility in the interconnection of adjacent individual modules 31. If a smaller number of configurations is sufficient, the circuit arrangement 319 can also be designed more simply. Alternatively, additional semiconductor switches can be provided, enabling interconnection with more than two adjacent individual modules.

[0047] The control unit 23 is connected to a line 602, and an input signal 603 is supplied to the control unit 23 via line 602. The control unit 23 is configured to set one of the different configurations depending on the input signal 603.

[0048] Preferably, the battery 30 has at least five individual modules 31, 32, 33, and more preferably at least eight. This allows a suitable voltage profile to be generated at the battery 30, for example to produce an approximately sinusoidal output voltage.

[0049] Fig. Figure 3 shows a schematic representation of the operation of the battery 30. In the exemplary embodiment, the battery 30 has six individual modules 31 to 36. By appropriately controlling the individual modules 31 to 36, different configurations 30.1, 30.2, 30.3, 30.4, 30.5, 30.6 are possible; the individual modules can thus be dynamically interconnected in many different connection states by means of the connection arrangements 319.

[0050] In the first configuration 30.1, all six individual modules 31, 32, 33, 34, 35, 36 are connected in parallel, resulting in a low output voltage.

[0051] To the right of this, in the second configuration 30.2, three of the six individual modules are connected in parallel, resulting in a higher output voltage than in configuration 30.1, since two individual modules are connected in series between the battery terminals, thus creating an output voltage approximately twice as high as in configuration 30.1.

[0052] To the right of this, in the third configuration 30.3, two individual modules are connected in parallel, resulting in approximately three times the output voltage compared to configuration 30.1 with all individual modules connected in parallel.

[0053] In the fourth configuration 30.4, four individual modules are connected in series, and in two of the four individual modules, another individual module is connected in parallel.

[0054] In the fifth configuration 30.5, five individual modules are connected in series, and the sixth individual module is connected in parallel to one of the five individual modules.

[0055] In the sixth configuration 30.6, all six individual modules are connected in series, resulting in the highest output voltage.

[0056] Similarly, the six individual modules can be connected in reverse direction between terminals 37 and 38 to generate a negative or opposite output voltage of different magnitudes.

[0057] Such AC batteries 30 are therefore suitable for generating an alternating current and transferring electrical energy to a consumer or a network, and in reverse direction the AC battery 30 can be directly charged by an AC voltage network.

[0058] In summary, the different configurations differ at least partially from each other. - in the number of individual modules 31, 32, 33, 34, 35, 36 connected in series between terminal 37 and terminal 38, - in the number of individual modules connected in parallel 31, 32, 33, 34, 35, 36, and - in the connection direction of the electrochemical energy storage devices 321 between terminal 37 and terminal 38. This provides an output voltage U_A between terminal 37 and terminal 38, resulting from the respective configuration, and enables the battery to operate as an AC voltage source.

[0059] Fig. Figure 4 shows battery 30 in another configuration 30.7, in which three individual modules 31, 32, 33 are connected in series between terminals 37, 38 of battery 30, and three further individual modules 34, 35, 36 are not connected between terminals 37, 38. This results in a higher load on the individual modules 31, 32, 33 at the same current than if the individual modules 34, 35, 36 were connected in parallel.

[0060] Such decoupling of individual modules 31 to 36 is also possible, for example, in configurations 30.1, 30.2, 30.3, 30.4 and 30.5 of Fig. 3 possible.

[0061] Fig. Figure 5 shows battery 30 in configuration 30.1 of Fig. 3. In this configuration, all individual modules 31, 32, 33, 34, 35, 36 are connected in parallel, and this allows a comparatively high total current at low voltage.

[0062] Fig. Figure 6 schematically shows a vehicle 10 with a device 20. The device 20 has the battery 30, the control unit 23, at least one main consumer 40 and at least one auxiliary consumer 42.

[0063] The terminals 37, 38 of the battery 30 are connected to the main consumer 40 via lines 51, 52.

[0064] Battery 30 is connected to auxiliary load 42 via lines 53 and 54. Lines 53 and 54 can either correspond to terminals 37 and 38, or there may be an additional circuit within battery 30 that provides a lower DC voltage for auxiliary load 42.

[0065] The control unit 23 is connected to the battery 30 via a line 24, to the at least one main consumer 40 via a line 26 and to the at least one secondary consumer 42 via a line 25.

[0066] The at least one main consumer 40 preferably comprises at least one first main consumer from a main consumer group consisting of: - Electric motor for vehicle propulsion, - Heating, e.g. battery heating and interior heating, - Air conditioning, and - Air conditioning compressor.

[0067] The at least one secondary consumer 42 preferably comprises at least one first secondary consumer from a secondary consumer group consisting of: - Low-voltage electrical system, in particular 12 V electrical system, - Heating, e.g. for windows or side mirrors, seat heating, steering wheel heating, - Low beam headlights, - Fog lights, - Navigation device, and - Radio.

[0068] The following describes different process steps A) to D), which, with the aid of the control unit 23, enable advantageous temperature control and, in particular, heating of the battery 30. Vehicle batteries have a relatively narrow temperature range in which they can operate well and provide high performance. Therefore, for example, in winter it is advantageous to heat the battery 30 to a desired temperature as quickly as possible.

[0069] According to process step A), a first group of individual modules 31, 32, 33, 34, 35, 36 is subjected to a higher load by the control device than a second group of individual modules during a first period of time in order to generate a different state of charge of the individual modules 31, 32, 33, 34, 35, 36, and during a second period of time, which is temporally after the first period of time, at least some of the individual modules 31, 32, 33, 34, 35, 36 of the first group are connected in parallel by the control device with at least some of the individual modules 31, 32, 33, 34, 35, 36 of the second group in order to charge the individual modules of the first group at least partially by the individual modules of the second group and thereby generate heat.

[0070] For example, configuration 30.7 can be used before the vehicle is switched off, or during the after-run of a ventilation system, and thus during the initial period. Fig. 4 or a corresponding configuration with a different output voltage U_A and disconnected individual modules can be set to discharge the individual modules 31, 32, 33 connected between terminals 37, 38 more strongly than the individual modules 34, 35, 36. Subsequently, during the second period, the individual modules 34, 35, 36 can be connected in parallel with the individual modules 31, 32, 33, thereby charging the individual modules 34, 35, 36. The currents flowing internally during this process result in power loss and thus heat generation. Heat is also generated in the electrochemical energy storage device 321 during the charging and discharging processes. As a result, the battery 30 heats up, although a current does not necessarily have to flow through terminals 37, 38.

[0071] According to procedure step B), when the main consumer 40 is active and connected to the battery, the control unit 23 controls the battery 30 in such a way that a part of the individual modules 34, 35, 36 (see Fig. 4) is not connected between the first terminal 37 and the second terminal 38 in order to increase the load on the remaining individual modules 31, 32, 33 and thereby generate additional heat in the remaining individual modules 31, 32, 33. This process step is also possible with the vehicle 10 in motion by driving the electric motor of the vehicle 10 as the main consumer 40.

[0072] According to process step C), when the main load is active and connected to the battery, the control unit 23 controls the battery 30 such that at least some of the individual modules have further individual modules connected in parallel. This reduces the internal resistance of the parallel-connected individual modules relative to the internal resistance of a single individual module and generates additional heat. Examples of this are configurations 30.2 and 30.3. The reduced internal resistance also improves cold-start capability. Parallel connection is particularly possible at low speeds of an electric motor, as the required voltage is lower at these speeds.

[0073] According to process step D), an auxiliary load 42 is activated by the control unit 23, and the auxiliary load 42 is supplied with electrical energy by the battery 30, whereby a majority of the individual modules are connected in parallel to each other in order to heat the majority of the individual modules. This is the case, for example, in configuration 30.1 or 30.2. This allows the battery 30 to be heated evenly. In addition, the parallel connection allows comparatively high currents, leads to a reduction in internal resistance, and enables higher currents to flow even at low temperatures.

[0074] Preferably, at least one of the process steps A) to D) is carried out to temperature-control the battery 30, more preferably at least two, more preferably at least three, and particularly preferably all four process steps A) to D). Each of the process steps enables additional heating of the battery 30, and the use of several of the process steps enables faster heating of the battery 30.

[0075] Preferably, in step B), in step C), or in both step B) and step C), an electric motor for a vehicle is provided as the main consumer 40, and the speed of the electric motor is limited by the control device 23. Limiting the speed of the electric motor protects the individual modules 31 to 36 from excessive load.

[0076] Naturally, various variations and modifications are possible within the scope of the present invention.

Claims

[1] Method for operating a battery (30) by means of a control device (23), which battery (30) is designed as a vehicle battery, has a first connection (37), a second connection (38) and a plurality of individual modules (31, 32, 33, 34, 35, 36), which individual modules (31, 32, 33, 34, 35, 36) each comprise an electrochemical energy store (321) and a circuit arrangement (319), which control device (23) is designed to enable different configurations of the individual modules (31, 32, 33, 34, 35, 36) between the first connection (37) and the second connection (38) by controlling the circuit arrangements (319), which different configurations (30.1 - 30.6) differ at least partially from one another - in the number of individual modules (31, 32, 33, 34, 35, 36) connected in series between the first terminal (37) and the second terminal (38), - in the number of individual modules connected in parallel (31, 32, 33, 34, 35, 36), and - in the connection direction of the electrochemical energy storage devices (321) between the first terminal (37) and the second terminal (38), in order to thereby provide an output voltage (U_A) resulting from the respective configuration (30.1 - 30.6) between the first terminal (37) and the second terminal (38) and to enable operation of the battery as an AC voltage source, which method is designed to carry out at least one of the following steps A) to D) for tempering the battery (30): A) A first group of individual modules (31, 32, 33, 34, 35, 36) is subjected to a greater load by the control device during a first period of time than a second group of individual modules (31, 32, 33, 34, 35, 36) in order to generate a different charge state of the individual modules (31, 32, 33, 34, 35, 36), and during a second period of time, which is after the first period of time, at least some of the individual modules (31, 32, 33, 34, 35, 36) of the first group are connected in parallel with at least some of the individual modules (31, 32, 33, 34, 35, 36) of the second group by the control device (23) in order to charge the individual modules (31, 32, 33, 34, 35, 36) of the first group at least partially by the individual modules (31, 32, 33, 34, 35, 36) of the second group and thereby generate heat; B) When the main consumer (40) connected to the battery (30) is active, the battery (30) is controlled by the control device (23) in such a way that some of the individual modules (31, 32, 33, 34, 35, 36) are not connected between the first connection (37) and the second connection (38) in order to place a greater load on the remaining individual modules (31, 32, 33, 34, 35, 36) and thereby generate additional heat; C) When the main consumer (40) is active and connected to the battery (30), the battery (30) is controlled by the control device (23) in such a way that at least some of the individual modules (31, 32, 33, 34, 35, 36) have further individual modules (31, 32, 33, 34, 35, 36) connected in parallel in order to reduce the internal resistance of the parallel-connected individual modules (31, 32, 33, 34, 35, 36) relative to the internal resistance of an individual individual module (31, 32, 33, 34, 35, 36) and thereby generate additional heat; D) An auxiliary consumer (42) is activated by the control device (23), and the auxiliary consumer (42) is supplied with electrical energy by the battery (30), wherein a plurality of the individual modules (31, 32, 33, 34, 35, 36) are connected in parallel to one another in order to heat the plurality of the individual modules (31, 32, 33, 34, 35, 36). [2] Method according to claim 1, which is designed to carry out at least two of the steps A) to D) for tempering the battery (30). [3] Method according to claim 1 or 2, which is designed to carry out at least three of the steps A) to D) for tempering the battery (30). [4] Method according to one of the preceding claims, which is designed to carry out all steps A) to D) for tempering the battery (30). [5] Method according to one of the preceding claims, in which an electric machine for a vehicle (10) is provided as the main consumer (40), and in which in step B), in step C) or in step B) and in step C) the speed of the electric machine is limited by the control device (23). [6] Device (20) comprising a battery (30) and a control device (23), which battery (30) comprises a first terminal (37), a second terminal (38) and a plurality of individual modules (31, 32, 33, 34, 35, 36), which individual modules (31, 32, 33, 34, 35, 36) each comprise an electrochemical energy store (321) and a circuit arrangement (319), which control device (23) is designed to enable different configurations (30.1 - 30.6) of the individual modules (31, 32, 33, 34, 35, 36) between the first terminal (37) and the second terminal (38) by controlling the circuit arrangements (319), which different configurations (30.1 - 30.6) differ at least partially from one another - in the number of individual modules (31, 32, 33, 34, 35, 36) connected in series between the first terminal (37) and the second terminal (38), - in the number of individual modules connected in parallel (31, 32, 33, 34, 35, 36), and - in the connection direction of the electrochemical energy storage devices (321) between the first terminal (37) and the second terminal (38), in order to thereby provide an output voltage (U_A) resulting from the respective configuration (30.1 - 30.6) between the first terminal (37) and the second terminal (38) and to enable operation of the battery as an alternating voltage source, and which device is designed to carry out a method according to one of the preceding claims.

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