Monitoring device for an energy accumulator of a motor vehicle, and method for monitoring an energy accumulator of a motor vehicle

Abstract

The invention relates to a monitoring device (11) for an energy accumulator (10) of a motor vehicle, comprising at least one capture device (14) which is designed to capture at least one physical variable of the energy accumulator (10). The invention additionally relates to a method (100) for monitoring an energy accumulator (10) of a motor vehicle.

Description

[0001] Monitoring device for an energy storage device of a motor vehicle and method for monitoring an energy storage device of a motor vehicle

[0002] The invention relates to a monitoring device for an energy storage device of a motor vehicle, comprising at least one detection device configured to detect at least one physical quantity of the energy storage device. The invention also relates to a method for monitoring an energy storage device of a motor vehicle.

[0003] High-voltage storage systems, also known as traction batteries or accumulators, are used to provide electrical energy for powering electric motors in motor vehicles. These systems typically consist of battery cells connected in parallel and series via a contacting device, all housed within a casing. As with most hazardous materials containers, high-voltage storage systems are required to detect thermal events. A pressure sensor is a particularly common solution. This sensor is designed to reliably detect pressure increases caused by hot venting in a battery cell and can transmit this information to a central control unit to trigger further actions, such as issuing a warning and / or initiating countermeasures.

[0004] Since such a pressure sensor must be located within the cell assembly or the interior of the high-voltage battery, it is typically installed on a cell supervisory circuit (CSC). This circuit is mounted close to the battery cells and is powered directly by the battery cells. This also enables emergency operation when the vehicle is asleep, as the power supply is never switched off.

[0005] Against this background, an object of the invention is to improve a monitoring device for an energy storage device of a motor vehicle. In particular, the monitoring device is to be improved in such a way that its energy supply can be improved.

[0006] This problem is solved by a monitoring device for an energy storage device of a motor vehicle with the features of claim 1 and a method for monitoring an energy storage device of a motor vehicle with the features of claim 9. The dependent claims relate to advantageous embodiments of the invention.

[0007] According to a first aspect, a monitoring device for an energy storage device of a motor vehicle is specified, comprising at least one detection device which is configured to detect at least one physical quantity of the energy storage device, wherein the detection device is connected for power supply to a quiescent current transformer which is configured to reduce an input voltage extractable from the energy storage device and to provide it as an output voltage for the detection device.

[0008] This improves the power supply to the monitoring device because the detection unit can be supplied with energy or voltage via the quiescent current converter, and not, as in prior art solutions, by a predetermined number or arrangement of a portion of the battery cells in a high-voltage storage system. In such prior art designs, the detection unit is typically supplied by only a portion of the battery cells, causing this portion to discharge. A process called "balancing" is then required to bring the remaining battery cells or modules to the same state of charge in order to ensure, for example, a safe and / or efficient charging process. This process results in wasted energy.This can be remedied by the present monitoring device, thereby improving the energy utilization and / or provision of the high-voltage storage system. The energy storage system is, in particular, a high-voltage storage system or a traction battery for a motor vehicle, comprising multiple battery cells. The housing of the high-voltage storage system defines an interior space in which the battery cells are housed or arranged. Cylindrical battery cells are primarily used, which can be provided in a packing arrangement or cell pack. Of course, battery cells with other cross-sections, such as rectangular, hexagonal, or prismatic cross-sections, or pouch cells, can also be used. A battery management system (BMS) of the motor vehicle can be configured to monitor and / or control the battery cells of a battery pack or cell pack.A cell supervisory circuit (CSC) can, for example, monitor the voltage, temperature, and / or state of charge of each individual battery cell, particularly within a cell array of a predetermined number of cells. It can also perform passive or active cell balancing to ensure all cells are at the same voltage level, thus improving the lifespan of the battery pack or cell assembly. Furthermore, the cell supervisory circuit can be configured to detect anomalies such as over- and / or undervoltage, short circuits, and / or thermal issues, and can be configured to initiate protective measures such as shutting down the battery pack.

[0009] A detection device is, in particular, a sensor or component that can detect a physical and / or chemical quantity from its environment and convert it into a signal and / or data. This signal can be transmitted to a (data) processing unit or control unit for processing.

[0010] The invention is based, among other things, on the idea of ​​supplying energy to a monitoring device for the high-voltage storage system or its battery cells, rather than supplying energy to individual battery cells, cell packs, or modules. This is because, particularly when the vehicle is not actively driven but in a standby or partial-load state, only these individual battery cells, cell packs, or modules are discharged, resulting in an uneven charge across the cell pack of all battery cells. This uneven charge must be compensated for by "balancing" or actively discharging the remaining battery cells. To this end, it is proposed to supply such a monitoring device with energy via a quiescent current converter.In this context, a quiescent current transformer (voltage transformer) is a device or circuit designed to provide, measure, and / or monitor quiescent current, i.e., the current that can flow in the vehicle's standby mode. Quiescent current is specifically the current consumed when the vehicle is switched off because some electrical systems remain operational, such as an alarm system and / or a central control unit. The quiescent current transformer is electrically connected to the energy storage device or its battery cell pack and is configured to transform its electrical current and / or voltage to a lower level. For this purpose, the quiescent current transformer is connected to the energy storage device being monitored and is configured to reduce the input voltage drawn from the energy storage device and provide it as the output voltage for the monitoring device.The quiescent current converter can, for example, include a voltage converter and / or a voltage regulator, which may be configured to convert the high-voltage DC voltage (input voltage) provided by the energy storage device into low-voltage DC voltage (output voltage). In some embodiments, a buck converter may be provided, which is configured to reduce the high input voltage to a lower output voltage, and / or an inverter, a transformer, and a rectifier, wherein the transformer is configured to reduce the input voltage and the rectifier is configured to convert the AC voltage back into DC voltage. Furthermore, such a quiescent current converter can provide separation between high- and low-voltage ranges. Because such a quiescent current converter is powered by all the battery cells of the high-voltage storage device or energy storage device,This allows for a uniform discharge of all battery cells in the energy storage system. This eliminates the need for battery cell balancing, which is required by the power supply to the detection device. Furthermore, such a quiescent current converter can provide a suitable voltage supply for the detection devices, particularly within the interior of the energy storage system or its housing.

[0011] In one embodiment, the quiescent current converter is configured to supply a low-voltage system of the vehicle. The quiescent current converter can be connected to the low-voltage system to provide the converted output voltage, for example, 12 V, 24 V, or 48 V. This allows components of the low-voltage system to be supplied with voltage or current even when the vehicle is at rest, particularly on a continuous basis. Since this quiescent current converter is connected across the entire voltage range of the energy storage system, not only individual battery cells are discharged locally, but the entire battery system is affected.

[0012] In one embodiment, the input voltage, particularly on a primary side of the quiescent current converter, can be between 48 V and 1000 V, and / or the output voltage, particularly on a secondary side of the quiescent current converter, can be between 8 V and 60 V. This eliminates the need for a conventional 12 V battery in some embodiments. Such a wide voltage conversion range allows the detection device to be adequately powered, or according to its specifications, to maintain reliable operation and / or monitoring of the high-voltage storage system, especially when the vehicle is stationary. In one embodiment, the quiescent current converter is located within a housing of the energy storage system. This allows for a localized electrical connection between the quiescent current converter and the battery cells or cell pack, thereby saving installation space and / or weight.

[0013] In one embodiment, at least one detection device is arranged inside the housing. This arrangement within the housing enables reliable monitoring of at least one physical and / or chemical parameter or quantity within the energy storage device's housing, thereby improving the safety of the high-voltage storage system.

[0014] In one embodiment, the at least one detection device is arranged on the quiescent current transformer, particularly on its secondary side. This allows for a direct power supply to the detection device by the quiescent current transformer. Furthermore, in some embodiments, the detection device can be integrated onto a circuit board or carrier board of the quiescent current transformer, thereby improving the mounting of the monitoring device in a high-voltage storage system.

[0015] In one embodiment, the detection device is a pressure sensor, where the physical quantity can be an internal pressure or a pressure change within the housing. This allows a pressure change, particularly one caused by a thermal event or hot venting of a battery cell, to be converted into a signal and provided to a suitable (data) processing device in order to trigger appropriate warnings and / or protective measures.

[0016] In other embodiments, the detection device can be, for example, a temperature sensor, an optical sensor, a current and / or voltage sensor, a hydrogen sensor, and / or a carbon monoxide sensor. By providing a temperature sensor, the temperature within the high-voltage storage unit can be monitored to provide improved safety for the high-voltage storage unit through thermal monitoring. An optical sensor can, for example, detect mechanical damage to the housing of the high-voltage storage unit, while a current and / or voltage sensor can be used for current and voltage monitoring, particularly for solar charging. Furthermore, other detection devices and / or sensors can be powered by the quiescent current transformer and / or connected to it.These sensors can be arranged on the vehicle and, for example, detect air exchange, humidity, and / or leakage information, particularly within the energy storage system. This allows for comprehensive monitoring of the energy storage system, even when the vehicle is stationary, because the sensor or detection device can be powered by the quiescent current converter in an energy-saving and / or permanent manner. Naturally, a monitoring device can also have several such detection devices to monitor a range of parameters.

[0017] In one embodiment, the monitoring device includes a storage unit that is connected to the quiescent current converter for power supply and is configured to at least temporarily store data or a signal that is acquired by the detection device or provided depending on the detected quantity. This enables the analysis of acquired measured values ​​and / or data, which can also be stored when the vehicle is at rest, since the storage unit can be powered by the quiescent current converter in an energy-efficient manner.

[0018] According to another aspect, an energy storage device or high-voltage storage device for a motor vehicle is described, comprising a cell pack of battery cells housed in a casing, a quiescent current converter electrically connected to this cell pack, and a monitoring device proposed herein. The effects and / or advantages described herein can, of course, be utilized by means of such a high-voltage storage device.

[0019] According to a further aspect, a method for monitoring a motor vehicle energy storage device is proposed, comprising the steps of reducing an input voltage available from the energy storage device by means of a quiescent current transformer, providing the reduced input voltage as an output voltage by means of the quiescent current transformer, supplying at least one detection device with the output voltage, and detecting at least one physical quantity of the energy storage device by means of the at least one detection device. This method can be carried out, in particular, by means of a monitoring device described herein. The proposed method allows the effects and advantages already and subsequently described to be achieved and utilized accordingly.

[0020] In one embodiment, the method includes the additional step of transmitting the data acquired by the sensing device to a processing device. Here, the measured values ​​acquired by the sensing device can be converted into a signal and / or data, and this signal and / or data can be processed directly by the processing device to enable a timely response to any critical measured values. In particular, monitoring of the energy storage system can be improved to allow for better utilization of electrical energy provided or potentially provided by the energy storage system.

[0021] In one embodiment, the method includes the additional step of transmitting the acquired data to a storage device, which can be powered, in particular, by means of the quiescent current converter. This enables subsequent data processing and / or analysis of the measured values, especially over time, thereby facilitating improvements in the safety and / or operating parameters of the high-voltage storage system and / or the motor vehicle.

[0022] In one embodiment, the method includes the additional step of outputting its signal via an output device when the detection device registers that a threshold value with respect to the detected quantity has been exceeded. Here, a data processing device, particularly based on the measured value and / or signal, can use an output device or output means to, for example, issue a visual and / or audible warning and / or trigger a countermeasure, such as cooling and / or galvanic isolation of the energy storage device and / or the affected battery cell or cell packing area. A threshold value can, in particular, be a predetermined limit value that can, for example, characterize a pressure and / or temperature exceedance. This enables timely warning and / or the initiation of countermeasures.

[0023] In one embodiment, the method is applied when the vehicle is in a resting state or operating under partial load. This allows monitoring of the high-voltage storage system, which can be operated in an energy-efficient manner, since the energy supply for the detection device is provided by the quiescent current converter, offering potential savings compared to a conventional energy supply for a sensor within the energy storage system.

[0024] According to another aspect, a motor vehicle is specified that has a monitoring device and / or a high-voltage storage device proposed herein and / or is equipped to carry out a procedure described herein. This allows the described effects and / or advantages to be utilized.

[0025] Further advantages and application possibilities of the invention will become apparent from the following description in conjunction with the figures. Fig. 1 shows a schematic representation of an embodiment of an energy storage device for a motor vehicle comprising a monitoring device according to the present invention.

[0026] Fig. 2 shows a schematic flowchart of a method for monitoring an energy storage device of a motor vehicle according to the present invention.

[0027] Fig. 1 shows an energy storage device 10 of a motor vehicle comprising a monitoring device 11 for an energy storage device 10 of a motor vehicle according to an embodiment of the present disclosure in a schematic representation.

[0028] The energy storage device 10, or high-voltage storage device, comprises a cell pack 20 consisting of several (not shown) battery cells and / or battery packs configured to provide a voltage of 400 V, 800 V, or more for the operation and / or propulsion of the motor vehicle. This cell pack 20, together with a quiescent current converter 30 electrically connected to the cell pack, is housed in an interior space 13 of the energy storage device 10, which is bounded by a housing 12 of the energy storage device 10. The quiescent current converter 30 is configured to reduce the input voltage available from the energy storage device 10, or the cell pack 20, and provide it as an output voltage. The quiescent current converter 30 can be configured to convert the input voltage from approximately 48 V to 1000 V into an output voltage between 8 V and 60 V, thus supplying a low-voltage system 40 of the motor vehicle with electrical energy of a suitable voltage.

[0029] Furthermore, the monitoring device 11 is located in the interior space 13.

[0030] This monitoring device 11 includes a detection device 14 configured to detect at least one physical quantity of the energy storage device 10, here exemplified as a pressure sensor. In other embodiments, the detection device 14 can be configured as a temperature sensor, optical sensor, current / voltage sensor, or similar, and / or multiple detection devices 14 can be provided. The detection device 14 is connected to the quiescent current transformer 30 for power supply and is powered by the output voltage provided by the quiescent current transformer 30. The detection device 14 is arranged on the quiescent current transformer 30 or, as shown here, on a circuit board 31 of the quiescent current transformer.

[0031] The monitoring device 11 also includes a storage device 15, which is connected to the quiescent current transformer 30 for power supply and is configured to receive and at least temporarily store data acquired by the sensing device 14 (shown here by the dotted line). Furthermore, the storage device 15 and / or the sensing device 14 can be connected to a processing device 50, which is configured to monitor and / or process the acquired measured values ​​and, if necessary, output a signal via an output device, for example, when the sensing device 14 detects that a threshold value with respect to the acquired physical quantity has been exceeded. This improves monitoring and thus the safety of the energy storage system, particularly when the vehicle is at rest.

[0032] Fig. 2 shows a schematic flowchart of a method for monitoring an energy storage device of a motor vehicle according to the present invention, in particular by means of a monitoring device 11 from Fig. 1.

[0033] For example, in a standby state or partial load operation of the vehicle, in step a, an input voltage available from the energy storage device 10 or the cell pack 20 is reduced by means of a quiescent current converter 30. In step b, the reduced input voltage is provided as an output voltage by means of the quiescent current converter 30. In step c, the at least one detection device 14 is supplied with electrical energy by means of the output voltage, and in step d, at least one physical quantity of the energy storage device 10 is detected by means of the at least one detection device 14, in particular to detect a thermal event or hot venting of one of the battery cells. In step e, the detected physical quantity of the energy storage device 10 can be transmitted as data or a signal to the processing device 50, and this data or signal can also be transmitted to the storage device 15.In step g, an output device 16 of the motor vehicle can output a signal, in particular an acoustic and / or optical signal, if the detection device 14 detects that a threshold value with respect to the detected physical quantity has been exceeded, or if the processing device 50 determines that such an exceedance has occurred. This can improve the monitoring of an energy storage device in a motor vehicle.

[0034] REFERENCE MARK LIST

[0035] 10 Energy storage

[0036] 11 Monitoring device

[0037] 12 Housing 13 Interior

[0038] 14 Recording device

[0039] 15 Storage setup

[0040] 16 expenditure funds

[0041] 20 cell pack 30 quiescent current converters

[0042] 40 Low-voltage system

[0043] 50 processing units

[0044] 100 procedures

Claims

REQUIREMENTS 1. Monitoring device (11) for an energy storage device (10) of a motor vehicle, comprising at least one detection device (14) which is configured to detect at least one physical quantity of the energy storage device (10), wherein the detection device (14) is connected for power supply to a quiescent current transformer (30) which is configured to reduce an input voltage obtainable from the energy storage device (10) and to provide it as an output voltage for the detection device (14).

2. Monitoring device (11) according to the preceding claim, wherein the quiescent current converter (30) is configured to supply a low-voltage system (40) of the motor vehicle.

3. Monitoring device (11) according to one of the preceding claims, wherein the input voltage is between 48V and 1000V and / or the output voltage is between 8V and 60V.

4. Monitoring device (11) according to one of the preceding claims, wherein the quiescent current transformer (30) is arranged within a housing (12) of the energy storage device (10).

5. Monitoring device (11) according to one of the preceding claims, wherein the at least one detection device (14) is arranged inside the housing (12).

6. Monitoring device (11) according to one of the preceding claims, wherein the at least one detection device (14) is arranged on the quiescent current transformer (30).

7. Monitoring device (11) according to one of the preceding claims, wherein the detection device (14) is a pressure sensor.

8. Monitoring device (11) according to one of the preceding claims, wherein the monitoring device (11) has a storage device (15) which is connected to the quiescent current transformer (30) for power supply and is configured to store data acquired by means of the detection device (14) at least temporarily.

9. A method (100) for monitoring an energy storage device (10) of a motor vehicle comprises the steps of: a) reducing an input voltage available from the energy storage device (10) by means of a quiescent current transformer (30); b) providing the reduced input voltage as an output voltage; c) supplying at least one detection device (14) by means of the output voltage; d) detecting at least one physical quantity of the energy storage device (10) by means of the at least one detection device (14).

10. The method (100) according to the preceding claim, comprising the additional step: e) transmitting the recorded data to a processing facility (50).

11. Method according to one of the two preceding claims, comprising the additional step: f) transmitting the recorded data to a storage device (15).

12. Method (100) according to one of the three preceding claims, comprising the additional step: g) outputting a signal by means of an output means (16) when the detection device (14) detects an exceedance of a threshold value with respect to the detected physical quantity.

13. Method (100) according to one of the four preceding claims, wherein the method (100) is applied when the motor vehicle is in a resting state or in partial load operation.

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