Traction battery, battery management control device and method for operating traction battery

Abstract

The invention relates to a traction battery (1) of an electric or hybrid vehicle. The traction battery comprises a plurality of battery cells (2), a plurality of sensors (3) for monitoring the battery cells (2), at least one battery management control device (4), at least one reversible switching element (7-9) for disconnecting the battery cells (2) from external contacts (10, 11) of the traction battery (1), and a battery management control device (4) and at least one component (15, 16) arranged outside the traction battery the battery management control device (4) is designed to detect tampering of the traction battery (1), and wherein the battery management control device (4) has at least one protected microprocessor (5) having a protected memory area (6), the detected tampering is stored in a protected storage area (6) and the switching behavior of the at least one reversible switching element (7-9) is changed, a battery management control device (4) and a method for operating a traction battery (1).

Description

Technical Field

[0001] The invention relates to a traction battery, a battery management control device and a method for operating a traction battery. Background Art

[0002] Traction batteries or traction battery units for electric or hybrid vehicles have a large number of battery cells, which are connected in series and in parallel according to the required rated voltage and capacity. It is also known to combine the battery cells into battery modules, wherein the battery modules can be connected in series and / or in parallel. In addition, the battery cells are equipped with a large number of sensors in order to monitor the battery cells. For example, the sensors are designed as temperature sensors, voltage sensors and current sensors. In addition, the traction battery has at least one battery management control device. The battery management control device has a large number of tasks. The battery management control device mainly controls at least one reversible switching element (Schaltelement, or switching element) for disconnecting the battery cells from the external contacts of the traction battery. These reversible switching elements can be power semiconductors or relays, so-called contactors. Depending on the design of the traction battery, a pre-charging circuit can also be connected in parallel with the relay, and the pre-charging circuit consists of a further relay and a pre-charging resistor. Another task of the battery management control device is usually also insulation resistance measurement, in order to detect a short circuit to ground, for example. The battery management control device also has at least one communication connection to a component arranged outside the traction battery. These components are, for example, further control units, wherein the communication connection is, for example, a bus connection.

[0003] Traction batteries can be tampered with by different persons for various reasons. For example, a current sensor measuring a lower current value can be replaced in order to, for example, influence the maximum power output. There may also be attempts to install unauthorized software on the battery management control device. Tampering also includes replacing components with other unauthorized components or opening the traction battery housing without authorization. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a traction battery which reliably signals manipulation. A further technical problem is to provide a suitable battery management control device and to provide a suitable method.

[0005] This object is achieved by a traction battery according to the invention, a battery management control device according to the invention and a method according to the invention. Further advantageous embodiments of the invention are given in the description.

[0006] The traction battery according to the invention for an electric or hybrid vehicle comprises a plurality of battery cells, a plurality of sensors for monitoring the battery cells, at least one battery management control device, at least one reversible switching element for disconnecting the battery cells from external contacts of the traction battery, and at least one communication connection between the battery management control device and at least one component arranged outside the traction battery. The battery management control device is also designed to detect manipulation of the traction battery, wherein the battery management control device has at least one protected microprocessor with a protected memory area, wherein the detected manipulation is stored in the protected memory area and the switching behavior of the at least one reversible switching element is changed. The manipulation is thus reliably signaled to the user. In the case of pure communication, such as a warning message on a display unit or in an instrument cluster, there is the risk that the communication may also be manipulated. This risk does not exist according to the invention because the protected microprocessor changes the switching behavior so that this cannot remain unnoticed by the user, wherein all necessary elements for this are in the traction battery itself.

[0007] In one embodiment, the battery management control device is designed to delay the switching on of the at least one reversible switching element by a preset time interval compared to normal switching on. To this end, the time interval should be large enough so that the delayed switching on can be easily perceived. Preferably, the time interval is greater than / equal to 10 seconds.

[0008] In a further embodiment, the battery management control unit is designed such that the predefined time interval is increased when the traction battery is restarted. For example, the time interval is extended by a further 10 seconds. For this purpose, the protected microprocessor can access data in a protected memory area. In addition to increasingly clear warnings, tampering is also made less attractive because the startup process lasts longer and longer.

[0009] In a further specific embodiment, the battery management control unit is designed in such a way that, in the event of a predefined manipulation, the at least one reversible switching element is not switched on. This is done in the event of a manipulation that has a direct impact on operational safety.

[0010] In a further embodiment, the battery management control device is designed to generate a warning message and transmit the warning message via the communication connection. If the communication connection has not been tampered with, the user is doubly warned, i.e., by the changed switching behavior and by the warning message. If the connection has been tampered with, the reliable changed switching behavior still exists.

[0011] A battery management and control device according to the invention for a traction battery of an electric or hybrid vehicle is designed to detect and evaluate sensor data of the battery cells, wherein the battery management and control device is also designed to actuate at least one reversible switching element for disconnecting the battery cells from external contacts, wherein the battery management and control device has at least one communication interface for external communication outside the traction battery, wherein the battery management and control device is designed to detect manipulation of the traction battery, wherein the battery management and control device has at least one protected microprocessor with a protected memory area, wherein the detected manipulations are stored in the protected memory area and the switching behavior of the at least one reversible switching element is changed.

[0012] A method according to the invention for operating a traction battery according to the invention, wherein a battery management control unit is woken up by an external signal, wherein the battery management control unit checks the traction battery for tampering, wherein, if tampering is detected, the tampering is stored in a protected memory area and the switching behavior of the at least one reversible switching element is changed.

[0013] Regarding the design of the battery management control device and method, the contents are completely referred to the aforementioned implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention is described in detail below based on preferred embodiments. In the accompanying drawings:

[0015] Figure 1 shows a schematic block diagram of a traction battery and

[0016] Figure 2 A schematic flow chart of a method for operating a traction battery is shown. DETAILED DESCRIPTION

[0017] exist Figure 1, a traction battery 1 is shown in a highly schematic manner. The traction battery 1 has a plurality of battery cells 2 which are connected in series in order to generate a corresponding rated voltage of, for example, 400 V. Other battery cells, not shown, can be connected in parallel. The battery cells 2 are provided with various sensors 3 which are preferably designed as current sensors, voltage sensors and temperature sensors. Furthermore, a circuit can be provided for the battery cells 2 in order to implement cell balancing. The traction battery 1 also has a battery management control device 4 which has a protected microprocessor 5 with a protected memory area 6. In this case, the battery management control device 4 can have further microprocessors and memories. Furthermore, the traction battery 1 has three reversible switching elements 7-9 in the form of contactors. In this case, the switching element 7 is located between the positive pole of the line of the battery cell 2 and the external contact 10. The switching element 8 is located between the negative pole of the line of the battery cell 2 and the external contact 11. The switching element 9 is connected to the pre-charging resistor R V The battery management control device 4 is connected in series, wherein the series circuit is connected in parallel with the switching element 7. The figure also shows that the battery management control device 4 is connected to the battery controller 13 via a bus connection 12. The battery controller 13 prepares the data of the sensor 3 and performs cell balancing if necessary. The battery management control device 4 is also designed with a communication interface 14, which is designed as a bus interface, for example, in order to communicate with further external components, in particular control devices 15, 16. The traction battery 1 also has a housing 17.

[0018] Now according to Figure 2 The flowchart in Figure 1 The working principle is briefly explained. In the original state, all switching elements 7-9 are disconnected and the battery management control device 4 is asleep. At this time, most of the components of the battery management control device 4 can be completely turned off to save static current. If the battery management control device 4 receives a wake-up command from an external control device, the battery management control device wakes up (step S1). At this time, a check step is performed in the second step S2. The voltage and temperature of the battery cell 2 are thereby queried and an insulation resistance measurement is performed. In addition, the protected microprocessor 5 checks whether unverified changes have occurred to the software in the battery management control device. In addition, it is checked whether the housing 17 has been opened without authorization, whether components are missing or replaced. At this time, in the third step S3, it is determined whether possible tampering has occurred or whether previous tampering still exists in the storage area 6.

[0019] If no new manipulation or past manipulation is detected, then in step S4 the switching element 9 and the switching element 8 are closed and the intermediate circuit capacitor (not shown) is charged. If the intermediate circuit capacitor is then sufficiently precharged, in step S5 the switching element 7 is closed and then the switching element 9 is opened. The switching commands S for the switching elements 7-9 are generated by the battery management control device 4.

[0020] If, on the other hand, it is determined that there is a new manipulation or that a manipulation occurred in the past (stored in the memory area 6), then in step S6, a check is made as to whether the manipulation is relevant to operational safety. If this is the case, the manipulation is written to the memory area 6 and a warning message is generated, which is transmitted to the display unit (step S7). The switching elements S7-S9 remain open.

[0021] If, on the other hand, it is determined in step S6 that a manipulation has occurred, but this manipulation is not directly relevant to operational safety, then this manipulation is first written to the memory element 6 (step S8). Subsequently, in step S9, the switching on of the switching elements 7-9 is delayed, wherein the length of the delay depends on whether the manipulation is new or has already occurred in the past. In the latter case, the last delay is read out from the memory area 6 and further increased. If, on the other hand, the manipulation is new, then a delay of a predefined time interval (e.g. 10 seconds) is applied. The delay can be implemented in different ways. The switching elements 8, 9 are closed with a time delay and / or the switching element 7 is closed with a time delay. In each case, the traction battery 1 is fully activated with a time delay. In addition, a warning message is generated in step S10. If the warning message is suppressed by a manipulation (e.g. by a manipulation of the display unit), the user is still warned by the changed switching behavior. It should also be noted that step S9 includes steps S4 and S5, but with a time delay.

[0022] Reference numerals list

[0023] 1 Traction battery

[0024] 2 Battery Cells

[0025] 3 Sensors

[0026] 4 Battery management control equipment

[0027] 5. Microprocessor

[0028] 6 Storage Area

[0029] 7 Switching elements

[0030] 8 Switching elements

[0031] 9 Switching elements

[0032] 10 Contacts

[0033] 11 Contact

[0034] 12 Bus connection

[0035] 13 Battery Controller

[0036] 14 Communication Interface

[0037] 15 Control Equipment

[0038] 16 Control Equipment

[0039] 17 Housing

[0040] S On / off signal

[0041] Steps S1-S10

Claims

1. A traction battery (1) for an electric or hybrid vehicle, comprising a plurality of battery cells (2), a plurality of sensors (3) for monitoring the battery cells (2), at least one battery management control device (4), at least one reversible switching element (7-9) for disconnecting the battery cells (2) from external contacts (10, 11) of the traction battery (1), and at least one communication connection between the battery management control device (4) and at least one component (15, 16) arranged outside the traction battery, It is characterized in that A battery management control device (4) is designed to detect manipulations of a traction battery (1), wherein the battery management control device (4) has at least one protected microprocessor (5) having a protected memory area (6), wherein the detected manipulations are stored in the protected memory area (6) and the switching behavior of the at least one reversible switching element (7-9) is changed.

2. The traction battery according to claim 1, characterized in that The battery management control device (4) is designed to delay the switching on of the at least one reversible switching element (7-9) by a predetermined time period compared to normal switching on.

3. The traction battery according to claim 2, characterized in that The battery management control device (4) is designed such that the predefined time interval is increased when the traction battery (1) is connected again.

4. Traction battery according to any one of the preceding claims, characterized in that The battery management control device (4) is designed such that, in the event of a predefined manipulation, the at least one reversible switching element (7-9) is not switched on.

5. Traction battery according to any one of the preceding claims, characterized in that The battery management control device (4) is designed to generate a warning message and to transmit the warning message via the communication connection.

6. A battery management control device (4) for a traction battery (1) of an electric or hybrid vehicle, wherein: A battery management control device (4) is designed to acquire and evaluate sensor data of a battery cell (2), wherein the battery management control device (4) is also designed to actuate at least one reversible switching element (7-9) for disconnecting the battery cell (2) from external contacts (10, 11), wherein the battery management control device (4) has at least one communication interface (4) for external communication outside the traction battery (1), It is characterized in that A battery management control device (4) is designed to detect manipulations of a traction battery (1), wherein the battery management control device (4) has at least one protected microprocessor (5) having a protected memory area (6), wherein the detected manipulations are stored in the protected memory area (6) and the switching behavior of the at least one reversible switching element (7-9) is changed.

7. The battery management control device according to claim 6, characterized in that: The battery management control device (4) is designed to delay the switching on of the at least one reversible switching element (7-9) by a predetermined time period compared to normal switching on.

8. The battery management control device according to claim 7, characterized in that: The battery management control device (4) is designed such that the predefined time interval is increased when the traction battery (1) is connected again.

9. A method for operating a traction battery (1) having the features of claim 1, characterized in that A battery management control device (4) is awakened by an external signal, wherein the battery management control device (4) checks the traction battery (1) for tampering, wherein if tampering is detected, the tampering is stored in a protected memory area and the switching behavior of the at least one reversible switching element (7-9) is changed.

10. The method according to claim 9, characterized in that The switching on of the at least one reversible switching element (7-9) is delayed by a predetermined time interval compared to a normal switching on without tampering.

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