Battery system and electric vehicle

Abstract

The utility model belongs to the technical field of batteries, and discloses a battery system and an electric automobile, the battery system is composed of a first battery pack and a second battery pack, the first battery pack comprises a first battery pack and a first relay, and the first relay controls power-on or power-off of the first battery pack; the second battery pack is provided with a first interface, a second battery pack and a second relay, the second battery pack is connected with the first battery pack through the first interface, the second relay controls the second battery pack to be powered on or powered off, and when the second battery pack is powered off, the first interface is in a power-off state. The second relay is additionally arranged in the second battery pack, continuous high voltage of the interface is effectively avoided, the risk of mistaken electric shock of maintenance personnel is eliminated, personnel safety is guaranteed, meanwhile, even if the interface is aged and affected with damp, short circuit and electric leakage caused by high voltage can be prevented, and the stability and reliability of the battery system are remarkably improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery system and an electric vehicle. Background Technology

[0002] With the booming development of the new energy vehicle industry, the performance and safety of power batteries have become critical issues. In multi-battery pack connection systems, a relay is currently commonly used to control the power-on and power-off operations of the other auxiliary battery packs within the main battery pack. This method enables unified management of the battery pack group during vehicle operation, providing stable power support for the vehicle. However, when the main battery pack is powered off, the other auxiliary battery packs remain under high voltage, and high voltage continues to exist at their interfaces. This not only increases the risk of electric shock due to accidental contact by maintenance personnel, but also causes safety accidents such as short circuits and leakage due to factors such as interface aging and moisture, seriously threatening personnel safety and the stable operation of the vehicle. Utility Model Content

[0003] The main objective of this invention is to provide a battery system and electric vehicle that addresses the technical problem that in existing multi-battery pack connection systems, high voltage remains at the interface of the auxiliary battery pack after power is off, which can easily lead to safety hazards.

[0004] To achieve the above-mentioned utility model objectives, this utility model proposes a battery system, including a first battery pack and a second battery pack;

[0005] The first battery pack includes a first battery group and a first relay. The first battery group is connected to the first relay, and the first relay is used to control the power-on or power-off of the first battery pack.

[0006] The second battery pack includes a first interface, a second battery group, and a second relay. The first battery pack is connected to the second battery pack through the first interface, and the second battery group is connected to the first interface. The first terminal of the second relay is connected to the negative terminal of the second battery group, and the second terminal of the second relay is connected to the first interface. The second relay is used to control the power-on or power-off of the second battery pack, and the first interface is in a de-energized state when the second battery pack is powered off.

[0007] Furthermore, the first battery pack also includes a second interface, the first end of which is connected to the negative terminal of the first battery pack, and the second end of which is connected to the first end of the first interface via a high-voltage connection line.

[0008] Furthermore, the first battery pack also includes a third interface, a first end of the first relay is connected to the third interface, and a second end of the first relay is connected to the positive terminal of the first battery pack.

[0009] Furthermore, the first battery pack also includes a first BMS acquisition board. The first end of the first BMS acquisition board is connected to the line between the third interface and the first relay, and the second end of the first BMS acquisition board is connected to the first end of the second interface. The first BMS acquisition board is used to acquire the first data information of the first battery pack and interact with peripheral electrical devices.

[0010] Furthermore, the second battery pack also includes a second BMS acquisition board, which is connected to the second end of the first interface. The second BMS acquisition board is used to acquire second data information of the second battery pack and send the second data information to the first BMS acquisition board.

[0011] Furthermore, the first battery pack also includes a pre-charging circuit connected between the positive terminal of the first battery pack and the third interface, and the pre-charging circuit is connected in parallel with the first relay.

[0012] Furthermore, the pre-charging circuit includes a pre-charging relay, the first end of which is connected to the line between the first end of the first relay and the third interface, and the second end of which is connected to the line between the second end of the first relay and the positive terminal of the first battery pack.

[0013] Furthermore, the pre-charging circuit also includes a pre-charging resistor connected in series with the pre-charging relay, the pre-charging resistor being connected on the line between the second terminal of the pre-charging relay and the positive terminal of the first battery pack.

[0014] Furthermore, the first battery pack also includes a single-pack main negative relay, the first end of which is connected to the line between the third interface and the first end of the first relay, and the second end of which is connected to the line between the negative terminal of the first battery pack and the first end of the second interface.

[0015] This utility model also proposes an electric vehicle, including the battery system described in any of the above embodiments.

[0016] Beneficial effects:

[0017] This utility model discloses a battery system comprising a first battery pack and a second battery pack. The first battery pack includes a first battery group and a first relay, wherein the first battery group is connected to the first relay, and the first relay is used to control the power-on or power-off of the first battery pack. The second battery pack includes a first interface, a second battery group, and a second relay. The first battery pack is connected to the second battery pack through the first interface, and the second battery group is connected to the first interface. The first terminal of the second relay is connected to the negative terminal of the second battery group, and the second terminal of the second relay is connected to the first interface. The second relay is used to control the power-on or power-off of the second battery pack, and the first interface is in a de-energized state when the second battery pack is powered off. Therefore, by adding a second relay to the second battery pack, the continuous high voltage at the interface of the second battery pack is avoided, eliminating the risk of electric shock caused by maintenance personnel accidentally touching the interface, greatly ensuring personnel safety. At the same time, even if the interface ages or gets damp, it will not cause short circuits or leakage due to high voltage, thus improving the stability and reliability of the battery system. In addition, when the second battery pack fails, the software can automatically select the first battery pack to operate alone by closing the single-pack main negative relay and the first relay of the first battery pack, so as to realize single-pack operation, which facilitates the repair or replacement of the second battery pack. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall battery system according to an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the first battery pack according to an embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram of the second battery pack according to an embodiment of the present invention.

[0021] in:

[0022] 1. First battery pack; 2. Second battery pack;

[0023] 10. First battery pack; S1. First relay; OUT2. Second interface; OUT3. Third interface; 11. First BMS acquisition board; 12. Pre-charge circuit; S4. Single-pack main negative relay;

[0024] OUT1, First Interface; 20, Second Battery Pack; S2, Second Relay; 21, Second BMS Acquisition Board;

[0025] S3, pre-charge relay; R, pre-charge resistor.

[0026] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0027] It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0028] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly and specifically defined.

[0029] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0030] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0031] Reference Figures 1-3 This embodiment provides a battery system, including a first battery pack 1 and a second battery pack 2;

[0032] The first battery pack 1 includes a first battery group 10 and a first relay S1. The first battery group 10 is connected to the first relay S1, and the first relay S1 is used to control the power-on or power-off of the first battery pack 1.

[0033] The second battery pack 2 includes a first interface OUT1, a second battery group 20, and a second relay S2. The first battery pack 1 is connected to the second battery pack 2 through the first interface OUT1, and the second battery group 20 is connected to the first interface OUT1. The first end of the second relay S2 is connected to the negative terminal of the second battery group 20, and the second end of the second relay S2 is connected to the first interface OUT1. The second relay S2 is used to control the power-on or power-off of the second battery pack 2, and the first interface OUT1 is in a de-energized state when the second battery pack 2 is powered off.

[0034] In the above embodiments, this battery system is mainly applied to a structure of at least two battery packs connected in series. This embodiment takes the structure of a series dual battery pack as an example for explanation. It consists of two parts: a first battery pack 1 and a second battery pack 2. The first battery pack 1 includes a first battery group 10 and a first relay S1. The first battery group 10 is composed of multiple cells connected in series and / or in parallel. Its function is to store and release electrical energy. The first relay S1 here is a main positive relay. It is connected to the first battery group 10 and is mainly responsible for controlling the power-on or power-off operation of the first battery pack 1, and determining whether the first battery pack 1 supplies power to the outside.

[0035] The second battery pack 2 includes a first interface OUT1, a second battery group 20, and a second relay S2. The first interface OUT1 is a comprehensive output interface that can output high voltage positive and negative signals, CAN (Controller Area Network) lines, and DebugCAN lines. The high voltage positive and negative signals are used to transmit electrical energy, the CAN line is used for communication between the battery management system and other devices, and the DebugCAN line is mainly used for debugging and fault diagnosis. The second battery group 20 is also composed of multiple cells connected in series and parallel. The second relay S2 is a main negative relay. Its first end is connected to the negative terminal of the second battery group 20, and its second end is connected to the first interface OUT1. It controls the power-on or power-off of the second battery pack 2, and when the second battery pack 2 is powered off, it can make the first interface OUT1 in a de-energized state. The first battery pack 1 and the second battery pack 2 are connected through the first interface OUT1 to form a complete battery system. Therefore, by adding a second relay S2 inside the second battery pack 2, the continuous presence of high voltage at the interface of the second battery pack 2 is avoided, eliminating the risk of electric shock caused by maintenance personnel accidentally touching the interface, greatly ensuring personnel safety. At the same time, even if the interface ages or gets damp, it will not cause short circuits or leakage due to high voltage, thus improving the stability and reliability of the battery system.

[0036] Reference Figures 1-2 In one embodiment, the first battery pack 1 further includes a second interface OUT2, the first end of the second interface OUT2 is connected to the negative terminal of the first battery pack 10, and the second end of the second interface OUT2 is connected to the first end of the first interface OUT1 through a high-voltage connection line.

[0037] In the above embodiment, the first battery pack 1 further includes a second interface OUT2, the first end of which is connected to the negative terminal of the first battery pack 10, and the second end is connected to the first end of the first interface OUT1 of the second battery pack 2 via a high-voltage connection line. The second interface OUT2 is used to output CAN bus, high-voltage negative and other signals, so that the battery system can establish a communication connection with other components of the vehicle (such as motor controller, on-board charger, etc.), provide stable power to the vehicle's high-voltage equipment (such as drive motor, air conditioning compressor, etc.), and improve overall performance. The first interface OUT1 of the second battery pack 2 is the hub connecting the two battery packs. Its first end receives the connection from the second interface OUT2 of the first battery pack 1. At the same time, the second end of the first interface OUT1 is connected to the second battery pack 20 and the second relay S2. The second battery pack 20 and the second relay S2 are connected in series, and the first interface OUT1 is connected in parallel with the second battery pack 20 and the second relay S2, respectively. The first battery pack 1 also includes a third interface OUT3. The second interface OUT2 and the third interface OUT3 are the bridges for the first battery pack 1 to connect and interact with external devices. The second interface OUT2, the third interface OUT3, the first relay S1 and the first battery pack 10 form a series structure. The first relay S1 and the first battery pack 10 are located between the second interface OUT2 and the third interface OUT3 to ensure the normal operation of the battery system. When the first relay S1 is closed, the current starts from the positive terminal of the first battery pack 10, passes through the first relay S1 to the third interface OUT3, then returns to the second interface OUT2 through the external circuit, and finally returns to the negative terminal of the first battery pack 10, forming a complete circuit loop. The third interface OUT3 also has the function of outputting high voltage positive and negative, CAN line, DebugCAN line and other signals, which enhances the power supply flexibility of the battery system and improves the system communication reliability.

[0038] Reference Figures 1-2 In one embodiment, the first battery pack 1 further includes a first BMS acquisition board 11. The first end of the first BMS acquisition board 11 is connected to the line between the third interface OUT3 and the first relay S1, and the second end of the first BMS acquisition board 11 is connected to the first end of the second interface OUT2. The first BMS acquisition board 11 is used to acquire the first data information of the first battery pack 10 and interact with peripheral electrical devices.

[0039] In the above embodiment, the first battery pack 1 also includes a first BMS (Battery Management System) acquisition board. The first BMS acquisition board is a key component for realizing battery management and data acquisition functions. The first end of the first BMS acquisition board 11 is connected to the line between the third interface OUT3 and the first relay S1, and the second end of the first BMS acquisition board 11 is connected to the first end of the second interface OUT2, enabling the first BMS acquisition board 11 to monitor the status of the first battery pack 10 in real time. The first BMS acquisition board 11 can not only collect various data information and board temperature of the first battery pack 10, such as voltage, current, and temperature, but also interact with external electrical devices, transmit the collected data to external devices, and receive control commands from external devices. All BMS functional logic that interacts with the outside world is built on the first BMS acquisition board 11, which is convenient for operators to monitor and manage. At the same time, it can collect various data information of the first battery pack 10 in real time and accurately, providing detailed data support for the battery management system and realizing precise management of the battery pack.

[0040] Reference Figures 1-3 In one embodiment, the second battery pack 2 further includes a second BMS acquisition board 21, which is connected to the second end of the first interface OUT1. The second BMS acquisition board 21 is used to acquire second data information of the second battery pack 20 and send the second data information to the first BMS acquisition board 11.

[0041] In the above embodiment, the second battery pack 2 further includes a second BMS acquisition board 21. The second BMS acquisition board 21 is connected to the second end of the first interface OUT1. The second BMS acquisition board 21 is used to acquire the second data information of the second battery pack 20 and send the second data information to the first BMS acquisition board 11. The high-voltage connection line includes a communication connection line, a first high-voltage negative connection line, and a second high-voltage negative connection line. The communication connection line is used to connect the first BMS acquisition board 11 and the second BMS acquisition board 21. The first high-voltage negative connection line is used to connect the negative terminal of the first battery pack 10 and the positive terminal of the second battery pack 20. The second high-voltage negative connection line is used to connect the negative terminal of the second battery pack 20 and the positive terminal of the first battery pack 10. The first BMS acquisition board 11 is responsible for the summation function. The first battery pack 1 makes corresponding control according to the status of all batteries and the control signal of the upper-level controller. The power-down process of the dual BMS system for the battery pack begins when the first and second BMS acquisition boards are in the PowerOn state. After receiving the power-down command from the upper-level controller, the first BMS acquisition board 11 first disconnects the main positive relay (first relay S1) and checks whether it is stuck. If it is not stuck, it sends a flag to the second BMS acquisition board 21 to allow the main negative relay (second relay S2) to disconnect. Then, the second BMS acquisition board 21 disconnects the main negative relay and checks its sticking status. If it is normal, it sends a flag indicating that the main negative relay has been disconnected, and the main negative relay enters the Standby state. Finally, after receiving the main negative relay disconnection flag, the first BMS main negative relay also enters the Standby state. If sticking is detected between the main positive relay and the main negative relay during the process, the sticking fault is reported and the process is terminated, effectively avoiding safety hazards such as short circuits and overheating caused by relay sticking, and ensuring the safe operation of the battery system and related equipment. At the same time, the data of the first battery pack 10 and the second battery pack 20 are collected by the first BMS acquisition board 11 and the second BMS acquisition board 21 respectively, which can comprehensively and accurately grasp the status of the two battery packs and realize refined management.

[0042] Reference Figures 1-2 In one embodiment, the first battery pack 1 further includes a pre-charging circuit 12 connected between the positive terminal of the first battery group 10 and the third interface OUT3, and the pre-charging circuit 12 is connected in parallel with the first relay S1.

[0043] In the above embodiment, the first battery pack 1 further includes a pre-charging circuit 12. The pre-charging circuit 12 is connected between the positive terminal of the first battery pack 10 and the third interface OUT3, and is connected in parallel with the first relay S1. Its function is to pre-charge the capacitors and other loads in the circuit when the system is powered on, so as to avoid damage to the circuit components caused by the excessive current surge generated by the instantaneous charging of the capacitor when the first relay S1 is directly closed. Furthermore, the pre-charging circuit 12 includes a pre-charging relay S3, which is the core component of the pre-charging circuit 12. Its first end is connected to the line between the first end of the first relay S1 and the third interface OUT3, and its second end is connected to the line between the second end of the first relay S1 and the positive terminal of the first battery pack 10, and is connected in parallel with the first relay S1. The pre-charging relay S3 can limit the initial charging current when the system is powered on, thus protecting the circuit components. The pre-charging circuit 12 also includes a pre-charging resistor R, which is connected in series with the second terminal of the pre-charging relay S3 and the positive terminal of the first battery pack 10. This greatly reduces the current surge when the system is powered on, avoids damage to components from large current, and extends the service life of the components.

[0044] Furthermore, in the power-on process of the dual BMS system of the battery system, in the initial state, the first and second BMS acquisition boards are initialized and in Standby state. When the power-on command is received from the upper controller, the first BMS acquisition board 11 first checks whether the main positive and pre-charge relays S3 are stuck. If normal, it closes the pre-charge relay S3 and sends a flag bit allowing the main negative relay to be closed to the second BMS acquisition board 21. Then it checks whether the main negative relay is stuck. If not stuck, it closes the main negative relay and sends a closed flag bit. The second BMS acquisition board 21 enters the PowerOn state. When the first BMS acquisition board 11 receives the closed flag bit of the main negative relay, it closes the main positive relay and opens the pre-charge relay S3, and then enters the PowerOn state. If the main positive relay and the main negative relay are detected to be stuck, a sticking fault is reported and the process is terminated, which effectively ensures that the battery system can operate continuously and stably.

[0045] Reference Figures 1-2 In one embodiment, the first battery pack 1 further includes a single-pack main negative relay S4, the first end of which is connected to the line between the third interface OUT3 and the first end of the first relay S1, and the second end of which is connected to the line between the negative terminal of the first battery pack 10 and the first end of the second interface OUT2.

[0046] In the above embodiment, the first battery pack 1 further includes a single-pack main negative relay S4. The first terminal of the single-pack main negative relay S4 is connected to the line between the third interface OUT3 and the first terminal of the first relay S1, and its second terminal is connected to another line located between the negative terminal of the first battery pack 10 and the first terminal of the second interface OUT2, so that the single-pack main negative relay S4 can effectively control the circuit on / off of the negative terminal of the first battery pack 10. When the system is in normal operation, the single-pack main negative relay S4 is in the off state, and the first battery pack 1 and the auxiliary pack (second battery pack 2) work together to supply power to the system. When a problem is detected in the auxiliary pack, the system will immediately issue a command. First, disconnect the second relay S2 to cut off the connection between the negative terminal of the first battery pack 10 and the relevant circuit. Then, close the single-pack main negative relay S4 and the first relay S1. At this time, the first battery pack 1 enters the independent power supply state, providing the required power to the system alone. During the single-pack power supply process, the system will monitor various parameters of the first battery pack 1 in real time, such as voltage and current, to ensure its normal operation. When the problem of the auxiliary pack is resolved, the system will return to the dual-pack power supply mode according to the reverse process, that is, first disconnect the single-pack main negative relay S4, and then close the second relay S2, so that the first battery pack 1 and the auxiliary pack can work together again. Therefore, when the second battery pack 2 fails, through reasonable software logic, the system can choose to operate the first battery pack 1 alone, close the single-pack main negative relay S4 and the first relay S1 of the first battery pack 1 to achieve single-pack operation, so as to facilitate the repair or replacement of the second battery pack 2. It is not necessary to immediately stop the operation of the entire system for repair. Instead, the system can be maintained by single-pack power supply first, and the auxiliary pack can be repaired at an appropriate time, which improves the system's efficiency.

[0047] Reference Figures 1-3 This utility model also proposes an electric vehicle, including the battery system described in any of the above embodiments.

[0048] In the above embodiments, the electric vehicle includes the battery system described in any of the above embodiments. Through the dual relay design within the battery system, the first interface OUT1 is de-energized when the second battery pack 2 is powered off, eliminating the risk of electric shock caused by maintenance personnel accidentally touching the interface. At the same time, it avoids safety accidents such as short circuits and leakage caused by interface aging and moisture, ensuring personnel safety and vehicle operation stability.

[0049] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural or procedural transformations made based on the content of the present utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present utility model.

Claims

1. A battery system characterized by, The first battery pack and the second battery pack are connected through the first interface. The first battery pack comprises a first battery group and a first relay, the first battery group is connected with the first relay, and the first relay is used for controlling power-on or power-off of the first battery pack. The second battery pack comprises a first interface, a second battery group and a second relay, the first battery pack is connected with the second battery pack through the first interface, the second battery group is connected with the first interface, a first end of the second relay is connected with a negative electrode end of the second battery group, a second end of the second relay is connected with the first interface, the second relay is used for controlling power-on or power-off of the second battery pack, and the first interface is in a power-off state in a power-off state of the second battery pack.

2. The battery system of claim 1, wherein, The first battery pack further comprises a second interface, a first end of the second interface is connected with a negative electrode end of the first battery group, and a second end of the second interface is connected with a first end of the first interface through a high-voltage connection line.

3. The battery system of claim 2, wherein, The first battery pack further comprises a third interface, a first end of the first relay is connected with the third interface, and a second end of the first relay is connected with a positive electrode end of the first battery group.

4. The battery system of claim 3, wherein, The first battery pack further comprises a first BMS acquisition board, a first end of the first BMS acquisition board is connected on a line between the third interface and the first relay, a second end of the first BMS acquisition board is connected with a first end of the second interface, the first BMS acquisition board is used for acquiring first data information of the first battery group, and interacts with an external electrical device.

5. The battery system of claim 4, wherein, The second battery pack further comprises a second BMS acquisition board, the second BMS acquisition board is connected at a second end of the first interface, the second BMS acquisition board is used for acquiring second data information of the second battery group, and sends the second data information to the first BMS acquisition board.

6. The battery system of claim 3, wherein, The first battery pack further comprises a pre-charging circuit connected between a positive electrode end of the first battery group and the third interface, and the pre-charging circuit is connected in parallel with the first relay.

7. The battery system of claim 6, wherein, The pre-charging circuit comprises a pre-charging relay, a first end of the pre-charging relay is connected on a line between the first end of the first relay and the third interface, and a second end of the pre-charging relay is connected on a line between the second end of the first relay and the positive electrode end of the first battery group.

8. The battery system of claim 7, wherein, The pre-charging circuit further comprises a pre-charging resistor connected in series with the pre-charging relay, the pre-charging resistor is connected on a line between the second end of the pre-charging relay and the positive electrode end of the first battery group.

9. The battery system of claim 3, wherein, The first battery pack further comprises a single-pack main negative relay, a first end of the single-pack main negative relay is connected on a line between the third interface and the first end of the first relay, and a second end of the single-pack main negative relay is connected on a line between the negative electrode end of the first battery group and the first end of the second interface.

10. An electric vehicle, characterized by The battery system comprises the battery system according to any one of claims 1-9.

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