Method for heating a battery and control unit as well as a vehicle

Abstract

The invention relates to a method for heating a battery (1) of a vehicle (2), wherein the battery (1) is periodically supplied with a discharge current and a charging current by controlling a pulse inverter (3) connected to the battery (1) by means of a predetermined first pulse pattern (4), wherein a first frequency of the first pulse pattern (4) is between 10 kHz and 100 kHz.

Description

[0001] The invention relates to a method for heating or conditioning a battery, in particular a high-voltage battery. The invention further relates to a control unit suitable for carrying out the method, and to a vehicle with a control unit.

[0002] High-voltage batteries are used primarily in motor vehicles to store electrical energy for powering traction drives. These high-voltage batteries can provide a traction voltage of 60 to 1,500 volts DC and, in particular, have a storage capacity of 10 to 500 kWh.

[0003] A vehicle with a battery can be equipped with an electric motor as its drive source (traction drive). Such a vehicle can be, for example, a plug-in hybrid electric vehicle (PHEV) or an electric vehicle (EV), where the battery can be charged with external energy using a charging plug.

[0004] The battery cells of such a battery have a severely limited discharge and charge capacity at low temperatures of the internal active material. Consequently, the driving and charging performance of electric vehicles is very low when the battery, especially the high-voltage battery, has cooled down, for example, after a long period of inactivity.

[0005] While externally mounted heating elements or devices can provide some relief, they initially only heat the battery or cell casing. The temperature of the internal active material of the battery cells, however, only begins to rise after a time lag following the heating of the battery and cell casing. Furthermore, heating is inefficient due to heat losses during the warming of the cell casing, resulting in an overall insufficient heating effect.

[0006] From DE 10 2022 207 314 A1, a method and an arrangement for heating a vehicle battery are known. In this method, while the vehicle is stationary, the battery is periodically subjected to a discharge current and a charging current by controlling a pulse inverter connected to the battery using a predetermined pulse pattern, thereby heating it.

[0007] This conditioning (heating) of a battery usually takes place when the vehicle is stationary, especially after a longer period of inactivity.

[0008] It is well known that the engine compartment of a vehicle heats up due to the engine's heat output, thus providing an attractive shelter for various animals, such as martens, especially on cold days. If these animals are present in the engine compartment, they often gnaw on soft materials installed there. These materials include, for example, plastics and rubber used as hoses, lines, and sound-insulating mats. In the worst case, the damage caused by gnawing can lead to malfunctions in the vehicle's operation.

[0009] To prevent damage caused by martens, for example, materials are used in the engine compartment that the animals cannot gnaw on. Another alternative is to encapsulate vulnerable cables or hoses with a sufficiently resistant material. However, both of these alternatives involve additional costs and do not always prevent damage in the engine compartment caused by animals.

[0010] Another alternative is to install electrical accessories in the engine compartment that emit acoustic ultrasonic signals to deter and drive away animals.

[0011] These problems with regard to animals also exist with vehicles with (high-voltage) batteries, where the batteries are conditioned, especially in cold environments, and thus provide heat that attracts these animals.

[0012] A system and a method for heating a battery are known from WO 2020 / 135 734 A1.

[0013] The object of the present invention is to at least partially solve the problems cited with reference to the prior art. In particular, a method for conditioning a battery is to be proposed. Specifically, this method is also intended to deter animals, especially martens.

[0014] A method with the features according to claim 1 and a use with the features according to claim 7 contribute to solving these problems. Advantageous further developments are the subject of the dependent claims. The features listed individually in the claims can be combined with one another in a technologically meaningful way and can be supplemented by explanatory facts from the description and / or details from the figures, thereby showing further embodiments of the invention.

[0015] A method for heating a vehicle battery is proposed, wherein the battery is periodically supplied with a discharge current and a charging current by controlling a pulse inverter connected to the battery by means of a predetermined first pulse pattern, wherein a first frequency of the first pulse pattern is between 10 kHz [Hertz] and 100 kHz, in particular at least 15 kHz, preferably at least 20 kHz, in particular at most 80 kHz, preferably at most 65 kHz.

[0016] In particular, the process involves switching back and forth between a discharge current and a charging current at the aforementioned frequency.

[0017] In particular, during discharge, the energy drawn from the vehicle battery is temporarily stored in an energy storage device within the vehicle (and thus not used to power the vehicle) in order to subsequently be fed back into the battery via the charging current. In principle, any energy storage device that can be charged or supplied with the battery's discharge current within a specified frequency range (of the pulse inverter) can be used. In particular, the energy storage device can be an inductively operating energy storage device. The pulse inverter is specifically a bidirectional pulse inverter. The pulse inverter serves, in particular, to transfer the energy stored in the battery to the vehicle's at least one traction drive.

[0018] Reference is made to the explanations in DE 10 2022 207 314 A1 regarding battery conditioning. However, in contrast to the method in DE 10 2022 207 314 A1, a pulse pattern with a significantly higher frequency is used here.

[0019] Crucial to the present invention is not the design of the current signals or the current or voltage values, but rather the frequency of the pulse pattern. A first frequency is proposed here which has a deterrent effect, particularly on animals, preferably martens. This frequency lies significantly above or outside the frequency range audible to humans, so that the battery conditioning deters animals and is imperceptible to humans.

[0020] Preferably, the first frequency of the first pulse pattern is at least 25 kHz or even at least 30 kHz (i.e., beyond the frequency audible to humans). An upper limit for the first frequency is set particularly with regard to its deterrent effect on animals, or on specific animals such as martens.

[0021] In particular, the first pulse pattern is used exclusively for heating the battery while the vehicle is running. This means, specifically, that the first pulse pattern is not used to power the vehicle. Specifically, the first pulse pattern is only used when the vehicle is stationary.

[0022] In particular, the battery is additionally heated using a predefined second pulse pattern, where the second frequency of the second pulse pattern is less than 10 kHz, especially less than 5 kHz or even less than 1 kHz. For example, the second frequency of the second pulse pattern can be selected to be particularly suitable for the battery or its chemistry.

[0023] In particular, the second pulse pattern can be used to heat the battery in protected environments (e.g., in a garage or while driving). The second pulse pattern is therefore selected especially when animals entering or damaging the vehicle is not expected or anticipated.

[0024] In particular, battery heating is performed using either the first or the second pulse pattern. Specifically, battery heating with the first pulse pattern can also be performed at intervals. For example, the first pulse pattern can be repeated at specific time intervals, with the intervals selected to ensure that damage to the vehicle by an animal is ruled out within this time interval between two first pulse patterns. A time interval can be, for example, at least 20 seconds or at least one minute. The time interval can be, for example, at most 5 minutes or at most two minutes.

[0025] In particular, the respective pulse pattern (or the time intervals between, for example, two initial pulse patterns or between two secondary pulse patterns) can be manually selected via a user interface of the vehicle. A user interface can, for example, include an input device (e.g., a user interface in the vehicle, a smartphone, or similar) that communicates with or is connected to a control unit of the vehicle via signal transmission.

[0026] In particular, the first pulse pattern (exclusively, i.e., in addition to heating the battery) is used to deter animals.

[0027] In particular, the use of one (or the first) pulse pattern of a pulse inverter connected to the battery is proposed to deter animals from a vehicle, especially in the vicinity of the battery.

[0028] The process for heating a vehicle battery can comprise several steps. For example, in a first step, the battery temperature can be determined. This temperature determination can be done directly (by measuring the temperature at the battery) or indirectly (e.g., based on knowledge of the ambient temperature and the vehicle's stationary time, etc.). If the temperature is sufficiently high, no heating occurs. However, if the determined battery temperature falls below a certain threshold, heating can begin in a second step. During this second step, the battery can be subjected to a pulse pattern, in particular at least partially to the first pulse pattern. As part of the process (especially before or simultaneously with the first step), it can be determined whether the vehicle is stationary (or moving).The battery is heated (especially with the first pulse pattern) only when the vehicle is stationary (and the temperature falls below the limit).

[0029] The above (non-exhaustive) division of the process steps into first and second steps is primarily intended for differentiation purposes and does not impose any sequence or dependency. The frequency of the individual process steps can also vary. It is also possible that process steps may overlap, at least partially. In particular, the first and second steps may occur simultaneously. Specifically, the first and second steps may occur in the specified order (first step, then second step).

[0030] Furthermore, a control unit is proposed that is equipped, configured, or programmed to carry out the described procedure.

[0031] Furthermore, a motor vehicle is proposed, at least comprising a high-voltage battery and an associated traction drive, a pulse inverter and the described control unit.

[0032] The battery is specifically a high-voltage battery that supplies energy to the traction drive of a motor vehicle. However, the battery can also be any other type of battery. A vehicle is specifically a motor vehicle, particularly an electric vehicle or a hybrid vehicle. However, a vehicle can also be any other land, rail, water, air, or spacecraft, such as a drone or an air taxi.

[0033] The method can be implemented in particular in a control unit, the control unit being intended at least for the diagnosis, and possibly also for the operation, of the battery.

[0034] In particular, the motor vehicle includes a data processing system, e.g. the control unit, which has means for carrying out the steps of the procedure and / or has means that are suitably equipped, configured or programmed to carry out the steps of the procedure or that carry out the procedure.

[0035] The means include, for example, a processor and a memory in which instructions to be executed by the processor are stored, as well as data lines or transmission devices that enable the transmission of instructions, measurements, data or the like between the aforementioned elements.

[0036] The "means" may include, in particular, one or more of the following components: control(s), microcontroller, data storage, data connection, display devices (such as a display), counter or timer, at least one other sensor, a power source, etc.

[0037] Furthermore, a computer program is proposed, comprising commands which, when executed by a computer, cause the computer to perform the described procedure or the steps of the described procedure.

[0038] Furthermore, a computer-readable storage medium is proposed, comprising instructions which, when executed by a computer, cause it to perform the described procedure or the steps of the described procedure.

[0039] The explanations regarding the procedure are particularly applicable to the (motor) vehicle, the control unit and / or the computer-implemented procedure (i.e., the computer or the processor, the data processing system, the computer-readable storage medium) and vice versa.

[0040] The use of indefinite articles (“a”, “an”, “one”, and “ones”), particularly in the patent claims and the description reproducing them, is to be understood as such and not as a numeral. Accordingly, terms or components introduced by these articles are to be understood as occurring at least once and, in particular, may also occur multiple times.

[0041] It should be noted as a precaution that the numerical terms used here ("first", "second", etc.) primarily serve (only) to distinguish between several similar objects, quantities, or processes, and thus do not necessarily dictate any dependency and / or sequence between these objects, quantities, or processes. Should a dependency and / or sequence be required, this is explicitly stated here, or it will be obvious to a person skilled in the art upon studying the specific configuration described. Where a component can occur multiple times ("at least one"), the description of one of these components may apply equally to all or some of the multiple components, but this is not mandatory.

[0042] The invention and its technical context are explained in more detail below with reference to the accompanying figure. It should be noted that the invention is not limited to the exemplary embodiment shown. In particular, unless explicitly stated otherwise, it is also possible to extract aspects of the facts illustrated in the figure and combine them with other elements and findings from the present description. It should be emphasized that the figure, and especially the depicted dimensions, are only schematic. Fig. Figure 1 shows a vehicle in a side view.

[0043] Fig. Figure 1 shows a motor vehicle 2 with a battery 1 and an associated traction drive 8 as well as a control unit 7. The vehicle also includes a pulse inverter 3.

[0044] In the process, the battery 1 is periodically supplied with a discharge current and a charging current by controlling a pulse inverter 3 connected to the battery 2 by means of a predetermined first pulse pattern 4, wherein a first frequency of the first pulse pattern 4 is between 10 kHz and 100.

[0045] The first pulse pattern 4 is used exclusively for heating battery 1 during vehicle 2 operation. This means that the first pulse pattern 4 is not used to power vehicle 2. The first pulse pattern 4 is only used when the vehicle is stationary.

[0046] The heating of battery 1 can additionally be carried out using a predefined second pulse pattern 5, wherein a second frequency of the second pulse pattern 5 is less than 10 kHz.

[0047] Therefore, for example, in protected environments (e.g., in a garage or even while driving), the battery 1 can be heated using the second pulse pattern 5. The second pulse pattern 5 is selected when the entry of animals into or damage to the vehicle 2 by animals is not expected or is not anticipated.

[0048] Heating battery 1 with the first pulse pattern 4 can also be performed at intervals. For example, the first pulse pattern 4 can be repeated at specific time intervals, whereby the time intervals are selected such that damage to vehicle 2 by an animal can be ruled out within this time interval between two first pulse patterns 4.

[0049] The respective pulse pattern 4, 5 (or the time intervals between, for example, two first pulse patterns 4 or between two second pulse patterns 5) can be manually selected, for example, via a user interface 6 of the vehicle 2. A user interface 6 can, for example, comprise an input device (e.g., a user interface in the vehicle 2 or a smartphone or similar) that communicates with or is connected to a control unit 7 of the vehicle 2 via signal transmission.

[0050] In particular, the first pulse pattern 4 (exclusively, i.e., in addition to heating battery 1) is used to deter animals.

[0051] The method for heating battery 1 of vehicle 2 can, in particular, comprise several steps. For example, in a first step, the temperature of battery 1 can be determined. This determination of the temperature can be done, for example, directly (by measuring the temperature at battery 1) or indirectly (e.g., from knowledge of the ambient temperature and the stationary time of vehicle 2, etc.). If the temperature is sufficiently high, no heating takes place. However, if the determined temperature of battery 1 falls below a threshold, heating of battery 1 can be started in a second step. As part of the second step, battery 1 can be subjected to a pulse pattern 4, 5, in particular at least partially to the first pulse pattern 4. As part of the method (in particular before or simultaneously with the first step), it can be determined whether vehicle 2 is stationary (or moving).The heating of battery 1 (especially with the first pulse pattern 4) only occurs when the vehicle 2 is stationary (and the temperature falls below the limit). Reference symbol list 1 battery 2 vehicles 3 pulse inverters 4 first pulse pattern 5 second pulse pattern 6 User Interface 7 Control unit 8 Traction drive

Claims

[1] Method for heating a battery (1) of a vehicle (2), wherein the battery (1) is periodically supplied with a discharge current and a charging current by controlling a pulse inverter (3) connected to the battery (1) by means of a predetermined first pulse pattern (4), wherein a first frequency of the first pulse pattern (4) is between 10 kHz and 100 kHz; wherein the heating of the battery (1) is additionally carried out by means of a predetermined second pulse pattern (5), wherein a second frequency of the second pulse pattern (5) is less than 10 kHz; wherein the respective pulse pattern (4, 5) can be manually selected via a user interface (6) of the vehicle (2). [2] Method according to claim 1, wherein the first pulse pattern (4) is carried out during the operation of the vehicle (2) exclusively for heating the battery (1). [3] Method according to one of the preceding claims, wherein the heating of the battery (1) is optionally carried out with the first pulse pattern (4) or with the second pulse pattern (5). [4] Method according to one of the preceding claims, wherein the first pulse pattern (4) is used to deter animals. [5] Control unit (7) which is equipped, configured or programmed to carry out a method according to any of the preceding claims. [6] Vehicle (2), comprising at least a battery (1) and an associated traction drive (8), a pulse inverter (3) and a control unit (7) according to claim 5. [7] Use of a pulse pattern of a pulse inverter (3) connected to a battery (1) of a vehicle (2) for deterring animals from the vehicle (2), wherein the battery (1) is periodically supplied with a discharge current and a charging current by controlling the pulse inverter (3) by means of a predetermined first pulse pattern (4), wherein a first frequency of the first pulse pattern (4) is between 10 kHz and 100 kHz.

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