Battery system, vehicle and control method thereof

Abstract

The present disclosure relates to a battery system, a vehicle and a control method thereof. The battery system comprises: a battery pack assembly, a second switch, a voltage converter and a third switch, the battery pack assembly comprises at least two battery packs connected in series, each battery pack comprises a battery cell and a first switch for short-circuiting the battery cell, the first end of the second switch is connected to the first end of the battery pack assembly, the second end of the second switch and the second end of the third switch form a first output end of the battery system, the first input end of the voltage converter is connected to the first end of the second switch, the second input end of the voltage converter is connected to the second end of the battery pack assembly to form a second output end of the battery system, and the first end of the third switch is connected to the first output end of the voltage converter. By setting a voltage converter, the present application can discharge after boosting the voltage converter when the output voltage is reduced due to the removal of a faulty battery pack from the battery pack assembly.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and more specifically, to a battery system, a vehicle, and a control method for the vehicle. Background Art

[0002] In the related art, the battery module is composed of multiple single cells connected in series. It determines which module battery or modules have a fault and pushes the information of the faulty module battery to the user. The information is used for the user to disconnect the faulty module battery and reconnect the remaining module batteries in series. This solution has the problem that when there are too many faulty battery cells, the effective total voltage exceeds the allowable discharge voltage range, and the battery system cannot be charged and discharged normally. Summary of the invention

[0003] The purpose of the present application is to solve the problems existing in the prior art to at least a certain extent, and to provide a battery system, a vehicle and a control method thereof that can control the selective operation of a voltage converter in a battery system according to the fault state of the battery system, so as to adjust the output voltage of the battery system.

[0004] In order to achieve the above-mentioned object, the present application provides a battery system. The battery system comprises: a battery pack assembly, the battery pack assembly comprising at least two battery packs connected in series, each of the battery packs comprising a battery cell and a first switch for short-circuiting the battery pack;

[0005] a second switch, wherein a first end of the second switch is connected to a first end of the battery pack assembly, and a second end of the second switch is a first output end of the battery system;

[0006] a voltage converter, wherein a first input end of the voltage converter is connected to a first end of the second switch, and a second input end of the voltage converter is connected to a second end of the battery pack assembly to form a second output end of the battery system, wherein the first output end and the second output end form an output end group of the battery system for connecting an electrical device;

[0007] A third switch, wherein a first end of the third switch is connected to the first output end of the voltage converter, and a second end of the third switch is connected to the second end of the second switch.

[0008] Optionally, a battery, the battery being connected to the second output terminal of the voltage converter;

[0009] A unidirectional conductive element, wherein the unidirectional conductive element is arranged between the second switch and the first output terminal of the battery system, the positive electrode of the unidirectional conductive element is connected to the second end of the third switch, and the negative electrode of the unidirectional conductive element is connected to the third end of the third switch, wherein the electrical equipment is a steering motor.

[0010] Optionally, a controller is configured to control the conduction states of the first switch, the second switch, the third switch and the working state of the voltage converter according to the fault state of the battery pack assembly.

[0011] Optionally, the fault state of the battery pack assembly includes a no-fault state, a first fault state, a second fault state and a third fault state;

[0012] When the battery pack assembly is in a non-fault state, the controller is configured to control the first switch so that all battery packs in the battery pack assembly are connected to the battery system, control the second switch to be turned on, control the first end and the third end of the third switch to be turned on and the voltage converter to be inoperative or control the third switch to be turned off;

[0013] When the battery pack assembly is in a first fault state, the controller is configured to control the first switch corresponding to the faulty battery pack in the battery pack assembly to short-circuit the faulty battery pack, connect the remaining battery packs in the battery pack assembly to the battery system, control the second switch to be turned on, control the first end of the third switch to be turned on with the third end and the voltage converter not to work or control the third switch to be turned off;

[0014] When the battery pack assembly is in a second fault state, the controller is configured to control the first switch corresponding to the faulty battery pack in the battery pack assembly to short-circuit the faulty battery pack, connect the remaining battery packs in the battery pack assembly to the battery system, control the second switch to be disconnected, and control the first end and the second end of the third switch to be connected and the voltage converter to work;

[0015] When the battery pack assembly is in the third fault state, the controller is configured to control the first switch corresponding to the faulty battery pack in the battery pack assembly to short-circuit the faulty battery pack, and the remaining battery packs in the battery pack assembly are connected to the battery system, and the first end and the third end of the third switch are controlled to be conductive and the voltage converter is operated.

[0016] Optionally, the first switch is a single-pole double-throw switch, the positive electrode of the battery pack is the first end of the first switch, the second end of the first switch is connected to the positive electrode of the battery unit, the third end of the first switch is connected to the negative electrode of the battery unit to form the negative electrode of the battery pack, the battery pack assembly is formed by connecting the battery packs in series, and the first end and the second end of the first switch are in a normally-on state;

[0017] or;

[0018] The first switch is connected in parallel with the battery cell, the positive electrode of the battery cell is the positive electrode of the battery pack, the negative electrode of the battery cell is the negative electrode of the battery pack, and the first switch is in a normally-off state.

[0019] The present application also provides a vehicle, wherein the vehicle is provided with the above-mentioned battery system provided in the present application.

[0020] The present application provides a vehicle control method, wherein the vehicle is provided with the above-mentioned battery system provided by the present application, and the method comprises:

[0021] Optionally, obtaining fault information of the battery pack assembly;

[0022] Controlling the first switch according to the fault information and determining the fault state of the battery pack assembly;

[0023] The conduction states of the second switch and the third switch and the working state of the voltage converter are controlled according to the fault state, wherein the fault information includes fault information of the battery pack in the battery pack assembly.

[0024] Optionally, controlling the first switch according to the fault information and determining the fault state of the battery pack assembly includes:

[0025] According to the fault information of the battery pack in the battery pack assembly, controlling the first switch corresponding to the faulty battery pack in the battery pack assembly so that the first switch corresponding to the faulty battery pack short-circuits the faulty battery pack, and the remaining battery packs in the battery pack assembly are connected to the battery system;

[0026] Get the output voltage and value of the remaining battery packs in the battery pack assembly;

[0027] Determining whether the output voltage and value are within a preset voltage range;

[0028] If yes, it is confirmed that the battery pack assembly is in the first fault state;

[0029] If not, determining whether the output voltage and value are zero;

[0030] If not, it is confirmed that the battery pack assembly is in the second fault state;

[0031] If so, it is confirmed that the battery pack assembly is in the third fault state.

[0032] Optionally, controlling the conduction state of the second switch and the third switch and the working state of the voltage converter according to the fault state includes:

[0033] If it is confirmed that the battery pack assembly is in the first fault state, the second switch is controlled to be turned on, the third switch is turned off, or the first end and the third end of the third switch are connected and the voltage converter does not work;

[0034] If it is confirmed that the battery pack assembly is in the second fault state, the second switch is controlled to be disconnected, the first end of the third switch and the second end of the third switch are connected, and the voltage converter is operated so that the battery pack assembly is discharged by boosting the voltage through the voltage converter;

[0035] If it is confirmed that the battery pack assembly is in the third fault state, the first end and the third end of the third switch are controlled to be turned on, and the voltage converter works so that the vehicle's battery supplies power to the vehicle's steering motor through the voltage converter.

[0036] Optionally, if it is confirmed that the battery pack assembly is in the first fault state, the method further includes:

[0037] confirming the discharge power of the battery pack assembly according to the output voltage and value;

[0038] The rotation speed and output torque of the motor are controlled according to the voltage and value and the discharge power, and the first alarm information and the remaining maximum mileage information are output.

[0039] Optionally, if it is confirmed that the battery pack assembly is in the second fault state, the method further includes:

[0040] Determining the discharge power of the battery pack assembly according to the output voltage of the voltage converter;

[0041] The rotation speed and output torque of the motor are controlled according to the output voltage and the discharge power, and a second alarm message and remaining maximum mileage information are output.

[0042] Optionally, the method further comprises:

[0043] Circularly obtain the fault information of battery pack components;

[0044] Determine whether the battery pack components are faulty;

[0045] If not, a fault relief signal is output, and the first switch is controlled so that all battery packs in the battery pack assembly are connected to the battery system, the second switch is turned on, the third switch is turned off or the first end and the third end of the third switch are turned on and the voltage converter does not work.

[0046] Through the above technical solution, the battery system is provided with a second switch, a third switch and a voltage converter. By controlling the second switch and the third switch, the voltage converter can be selectively connected to the battery system. When the output voltage of the battery pack assembly is reduced due to the removal of a faulty battery pack and the electrical equipment cannot work normally, the voltage converter is connected to the battery system, and the battery pack assembly is discharged through the voltage converter to ensure the normal operation of the electrical equipment. At the same time, the battery system does not need to be equipped with a spare battery pack, saving costs.

[0047] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0049] Figure 1 is a schematic diagram of a circuit structure of a battery system provided by an exemplary embodiment;

[0050] Figure 2 is a circuit structure diagram of a battery system provided by another exemplary embodiment;

[0051] Figure 3 is a circuit structure schematic diagram of a battery system provided by another exemplary embodiment;

[0052] FIG. 4( a ) is a structural block diagram of a battery pack provided by an exemplary embodiment;

[0053] FIG4( b ) is a structural block diagram of a battery pack provided by yet another exemplary embodiment;

[0054] Figure 5 is a schematic diagram of a circuit structure of a battery system in a fault-free state provided by an exemplary embodiment;

[0055] Figure 6 is a circuit structure diagram of a battery system in a first fault state provided by an exemplary embodiment;

[0056] Figure 7 is a circuit structure diagram of a battery system in a second fault state provided by an exemplary embodiment;

[0057] Figure 8 is a circuit structure diagram of a battery system in a third fault state provided by an exemplary embodiment;

[0058] Fig. 9 is a schematic diagram of a vehicle circuit structure provided by an exemplary embodiment;

[0059] Fig.10 is a flow chart of a vehicle control method provided by an exemplary embodiment;

[0060] Fig.11 is a flowchart of a vehicle control method provided by yet another exemplary embodiment. DETAILED DESCRIPTION

[0061] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0062] Combine the following Figure 1-Figure 11 The battery system, vehicle and vehicle control method of the present application are described.

[0063] Figure 1 1 is a schematic diagram of a circuit structure of a battery system provided by an exemplary embodiment. The battery system may include a battery pack assembly, a second switch, a voltage converter and a third switch.

[0064] Wherein, the battery pack assembly includes at least two battery packs connected in series, each of the battery packs includes a battery cell and a first switch for short-circuiting the battery pack, the first end of the second switch is connected to the first end of the battery pack assembly and the first input end of the voltage converter, the second end of the second switch is the first output end of the battery system, the second input end of the voltage converter is connected to the second end of the battery pack assembly to form the second output end of the battery system, wherein the first output end and the second output end form an output end group of the battery system for connecting electrical equipment; the first end of the third switch is connected to the first output end of the voltage converter, and the second end of the third switch is connected to the second end of the second switch.

[0065] like Figure 1As shown, n battery packs in a battery pack assembly are connected in series, and each battery pack is provided with a battery cell and a first switch for short-circuiting the battery pack. The first switch is used to short-circuit the faulty battery pack when a battery pack fails, so that the faulty battery pack is removed from the battery pack assembly. The specific arrangement of the first switch can be used as long as the faulty battery pack can be short-circuited when the battery pack fails, and the present application is not limited to this. Specifically, the present disclosure provides two battery pack settings. The first setting is shown in FIG. 4(a). The first switch K1 is a single-pole double-throw switch. The positive electrode (+) of the battery pack is the first end a of the first switch K1. The second end b of the first switch K1 is connected to the positive electrode of the battery cell E. The third end c of the first switch is connected to the negative electrode of the battery cell E to form the negative electrode (-) of the battery pack. The first end a and the second end b of the first switch K1 are in a normally conducting state, so that the battery cell E is connected to the battery pack assembly. When the battery cell E fails, the first end a of the first switch K1 is connected to the third end c, so that the faulty battery pack is removed from the battery pack assembly. The second setting method is shown in Figure 4(b), where the first switch K1 is connected in parallel with the battery cell E, the positive electrode of the battery cell E is the positive electrode (+) of the battery pack, and the negative electrode of the battery cell E is the negative electrode (-) of the battery pack. The first switch K1 is in a normally open state. When a battery cell E fails, the first switch K1 is closed, short-circuiting the corresponding battery cell E, thereby short-circuiting the battery pack and ensuring the normal operation of the battery system.

[0066] In order to ensure the safety of battery power-on, a fuse resistor R may be provided inside the battery pack, and the fuse resistor R is connected in series between the positive electrode of the battery pack and the first switch K1.

[0067] like Figure 1 As shown, the voltage converter can be a boost DC or a bidirectional DC. The voltage converter has an input end and an output end. The input end includes a first input end and a second input end respectively connected to the positive and negative electrodes of the battery pack assembly, one end of the output end (i.e., the first output end) is connected to the first end of the third switch, and the other end of the output end is connected to the negative electrode of the battery pack assembly to form an output end of the battery system.

[0068] In this solution, the battery system is provided with a second switch, a third switch and a voltage converter. By controlling the second switch and the third switch, the voltage converter can be selectively connected to the battery system. When the output voltage of the battery pack assembly is reduced due to the removal of a faulty battery pack and the electrical equipment cannot work normally, the voltage converter is connected to the battery system, and the battery pack assembly is discharged through the voltage converter to ensure the normal operation of the electrical equipment. At the same time, the battery system does not need to be equipped with a spare battery pack, saving costs.

[0069] Figure 2It is a schematic diagram of the circuit structure of a battery system provided by an exemplary embodiment. The battery system is also provided with a fourth switch, which is connected between the second switch and the battery pack assembly, and is used to disconnect the battery pack assembly from other components of the battery system, realize the access of the battery pack assembly to the battery system and the shielding of the battery pack assembly, and ensure the charging and discharging safety of the battery system. As a shielding switch of the battery pack assembly, the fourth switch can also be set in the battery pack assembly. Among them, the first switch, the second switch, the third switch and the fourth switch can be triodes and can also be replaced by other switch tubes, for example, insulated gate bipolar transistors (IGBT), metal-oxide semiconductor field-effect transistors (MOSFET), etc.

[0070] Figure 3 It is a schematic diagram of the circuit structure of a battery system provided by another exemplary embodiment. The battery system also includes a battery and a unidirectional conductive element, the battery is connected to the second output terminal of the voltage converter, the unidirectional conductive element is arranged between the second switch and the first output terminal of the battery system, the positive electrode of the unidirectional conductive element is connected to the second end of the third switch, and the negative electrode of the unidirectional conductive element is connected to the third end of the third switch, wherein the electrical equipment is a steering motor. Specifically, the voltage converter has a second output terminal, and the second output terminal is a low-voltage output terminal. When the voltage converter is working, the battery pack assembly can be discharged by the voltage converter to charge the battery. The battery voltage platform can be 12V or 24V, and the present disclosure does not limit this. Among them, the unidirectional conductive element can be a diode D1. In this embodiment, the first end d and the third end f of the third switch are normally turned on. When the battery system of the present application is used in a vehicle, the electrical equipment may be a steering motor, an electronic control and a drive motor. When an abnormal high-voltage power failure occurs in the battery pack assembly, the battery can boost the output through the voltage converter to drive the steering motor. The first end d and the third end f of the third switch are normally turned on to ensure that electrical energy is output within 100ms of the high-voltage power failure to drive the steering system to work, thereby achieving emergency steering and ensuring the safety of the occupants. The setting of the unidirectional conduction element ensures that all electrical energy is provided to the steering motor instead of being used to achieve functions such as driving.

[0071] like Figure 5-8As shown, in this embodiment, taking the battery system applied to a vehicle as an example, the voltage converter can reuse the bidirectional DC of the bidirectional inverter system of the whole vehicle, the first input terminal I1 of the voltage converter is connected to the positive electrode of the battery pack assembly, and the second input terminal I2 is connected to the negative electrode of the battery pack assembly, the first output terminal (H1, H2) of the voltage converter can be a high-voltage output terminal, wherein the H2 terminal is connected to the I2 terminal in common, and the battery is connected to the second output terminal (L1, L2), the battery pack assembly can be boosted and output to the electrical equipment through the first output terminal (H1, H2) of the voltage converter, and can also be stepped down and output to charge the battery through the second output terminal (L1, L2); the battery can also be boosted and output to the steering motor through the first output terminal (H1, H2) of the voltage converter, and when the electrical equipment is a charging port, the charging port can selectively charge the battery pack assembly through the voltage converter according to the charging port voltage and the battery pack assembly voltage. In addition, during driving, the vehicle can maintain the braking effect consistent with the normal state of the vehicle through the brake feedback function, thereby improving the driving safety and driving feel of the vehicle. At the same time, the electric energy fed back by the driving motor is charged back to the battery pack assembly through bidirectional DC reverse charging, realizing the energy recovery function.

[0072] like Figure 1-3 As shown, the battery system further includes a controller, which is configured to control the conduction state of the first switch, the second switch, and the third switch and the working state of the voltage converter according to the fault state of the battery pack assembly. When the battery system is applied to a vehicle, the controller can be a battery management module or a vehicle controller. The controller is connected to the control end of the first switch, the second switch, the third switch, and the voltage converter, and is used to control the voltage converter to selectively work according to the fault state of the battery pack assembly, so as to adjust the output voltage of the battery system, and control the operation of the voltage converter according to the output voltage of the battery pack assembly and the required voltage of the electrical equipment.

[0073] According to the battery system of the embodiment of the present disclosure, the fault state of the battery pack assembly includes a no-fault state, a first fault state, a second fault state and a third fault state. Among them, the no-fault state indicates that all the battery packs in the battery pack assembly can work normally and the battery packs are in good health; the first fault state indicates that at least one battery pack in the battery pack assembly fails, and the discharge voltage of the remaining battery packs in the battery pack assembly is still within the working voltage range of the electrical equipment, for example, the preset working voltage range of the electrical equipment is (Umin, Umax), and the sum of the discharge voltages of the remaining battery packs in the battery pack assembly is greater than the minimum working voltage Umin of the electrical equipment; the second fault state indicates that at least one battery pack in the battery pack assembly fails, and the discharge voltage of the remaining battery packs in the battery pack assembly cannot drive the electrical equipment to work, for example, the preset working voltage range of the electrical equipment is (Umin, Umax), and the sum of the discharge voltages of the remaining battery packs in the battery pack assembly is not within the preset range; the third fault state indicates that the battery pack assembly is abnormally powered off, and the output voltage is zero.

[0074] When the battery pack assembly is in a non-fault state, the controller is configured to control the first switch to connect all battery packs in the battery pack assembly to the battery system, control the second switch to be turned on, control the first end and the third end of the third switch to be turned on and the voltage converter to be inoperative or control the third switch to be turned off. Figure 5 As shown, all the battery packs in the battery pack assembly are in normal working state, the first switch in the battery pack connects the battery cells so that the battery packs are connected in series to form a battery pack assembly, the second switch is turned on so that the battery pack assembly is directly connected to the electrical equipment, and the third switch can have two working states. In the first working state, the third switch is controlled to be disconnected, and the controller can not control the voltage converter. At this time, the voltage converter is not connected to the circuit for the battery pack assembly to discharge the electrical equipment, and the battery pack assembly directly supplies power to the electrical equipment; in the second working state, the first end and the third end of the third switch are controlled to be connected, and the voltage converter is connected to the steering motor. At this time, the voltage converter is controlled not to work, and the voltage converter is not connected to the circuit for the battery pack assembly to discharge the electrical equipment, and the battery pack assembly directly supplies power to the electrical equipment. However, when the battery pack assembly has an abnormal high-voltage power failure, it can be ensured that the voltage converter is controlled to work in time, so that the battery is boosted and discharged to the steering motor, driving the steering motor to work, and achieving steering safety in emergency situations.

[0075] When the battery pack assembly is in a first fault state, the controller is configured to control the first switch corresponding to the faulty battery pack in the battery pack assembly to short-circuit the faulty battery pack, connect the remaining battery packs in the battery pack assembly to the battery system, control the second switch to be turned on, control the first end and the third end of the third switch to be turned on and the voltage converter not to work or control the third switch to be turned off. Specifically, Figure 6 As shown, the battery pack 1 in the battery pack assembly fails, and the first terminal a and the third terminal c of the first switch K1 in the battery pack 1 are controlled to be connected, so that the battery pack 1 is short-circuited, and the remaining battery packs are connected to the battery system. The failed battery pack is removed from the battery pack assembly by controlling the first switch, which does not affect the discharge of the battery pack assembly. The discharge voltage of the remaining battery pack can drive the electrical equipment to work, and then the second switch K2 is controlled to be turned on. The third switch K3 has two working states. It is preferred to control the first terminal d and the third terminal f of the third switch K3 to be turned on, and the voltage converter is connected to the steering motor. At this time, the voltage converter is controlled not to work, and the voltage converter is not connected to the circuit of the battery pack assembly for discharging the electrical equipment. The battery pack assembly directly supplies power to the electrical equipment. However, when the battery pack assembly has a high-voltage abnormal power failure, the first terminal d and the third terminal f of the third switch K3 are turned on to ensure that the voltage converter is controlled to work in time, so that the battery is boosted and discharged to the steering motor, and the steering motor is driven to work, so as to achieve steering safety in emergency situations.

[0076] When the battery pack assembly is in the second fault state, the controller is configured to control the first switch corresponding to the faulty battery pack in the battery pack assembly to short-circuit the faulty battery pack, connect the remaining battery packs in the battery pack assembly to the battery system, control the second switch to be disconnected, and control the first end and the second end of the third switch to be conductive and the voltage converter to work. Specifically, Figure 7 As shown, the battery pack 1 and the battery pack x in the battery pack assembly fail, and the first end a and the third end c of the first switch K1 in the battery pack 1 and the battery pack x are controlled to be turned on, and the failed battery pack 1 and the battery pack x are removed from the battery pack assembly, and the remaining battery packs are connected in series as the battery pack assembly to the battery system. Since there are many failed battery packs, the output voltage of the battery pack assembly cannot meet the working voltage of the electric device, and the second switch K2 is controlled to be disconnected, and the first end d and the second end e of the third switch K3 are controlled to be turned on, and the voltage converter is controlled to work and connected between the battery pack assembly and the output end group. The output voltage of the battery pack assembly is converted by the voltage converter, such as boosting the output to supply power to the electric device. The setting of the voltage converter ensures that when the battery pack assembly fails and the output voltage cannot meet the working requirements of the electric device, the output voltage can be adjusted by the voltage converter, and the battery pack assembly can continue to discharge, ensuring that the electric device can enter the fault operation mode when the battery pack assembly fails. When the battery system is used for a vehicle, when the battery pack assembly fails, the battery pack failure driving mode can be entered, which improves the fault tolerance rate of the vehicle battery failure and prevents the vehicle from suddenly losing power and causing traffic hazards. In the battery pack failure driving mode, the vehicle can be driven to the maintenance station without the need for a rescue tow truck, greatly saving time and towing costs.

[0077] When the battery pack assembly is in the third fault state, the controller is configured to control the first switch corresponding to the faulty battery pack in the battery pack assembly to short-circuit the faulty battery pack, connect the remaining battery packs in the battery pack assembly to the battery system, and control the first end of the third switch to be conductive with the third end and the voltage converter to operate. Figure 8 As shown, when there is a battery pack failure in the battery pack assembly, the output voltage of the battery pack assembly is confirmed to be still zero after the faulty battery pack is removed, or when the output voltage of the battery pack assembly is zero when there is no failure in the battery pack assembly, it is confirmed that the battery pack assembly is in the third fault state, and the first end d and the third end f of the third switch K3 are controlled to be connected, and the voltage converter is operated, so that the battery drives the steering motor to work after the voltage is boosted and output through the voltage converter, so as to realize emergency steering when the vehicle has a driving speed due to inertia when the vehicle is powered off.

[0078] The present disclosure also provides a vehicle. Fig. 9 FIG. 1 is a circuit block diagram of a vehicle provided by an exemplary embodiment. Fig. 9 As shown, the vehicle may include a steering motor, a charging port, a motor control module, a drive motor and the above-mentioned battery system provided by the present disclosure. The vehicle of the present disclosure monitors the health status of the power battery pack in real time through the battery management module or the vehicle controller. When a battery failure occurs, the vehicle may enter the battery pack failure driving mode, thereby improving the fault tolerance rate of the vehicle battery failure and preventing the vehicle from suddenly losing power and causing traffic hazards.

[0079] The present disclosure also provides a vehicle control method, wherein the vehicle is provided with the battery system provided by the present disclosure. Figure 10-11 As shown, the control method comprises the following steps:

[0080] S11, obtaining fault information of the battery pack assembly.

[0081] The implementation of this step may include the following steps:

[0082] S110, the battery system receives a discharge request;

[0083] S111, determining whether a battery pack in the battery pack assembly fails, if so, executing step S112, if not, executing step S152;

[0084] S112, recording the fault information of all faulty battery packs in the battery pack assembly.

[0085] The fault information includes the fault information of the battery packs in the battery pack assembly, and the fault information may indicate which battery pack has failed. The battery manager monitors the health status of the battery packs in the battery pack assembly, and when one or more battery packs in the battery pack assembly fail, the fault information of the battery packs can be obtained in real time.

[0086] S12, controlling the first switch according to the fault information, and determining the fault status of the battery pack assembly.

[0087] The implementation of this step may include the following steps:

[0088] S121, according to the fault information of the battery pack in the battery pack assembly, controlling the first switch corresponding to the faulty battery pack in the battery pack assembly so that the first switch corresponding to the faulty battery pack short-circuits the faulty battery pack, and the remaining battery packs in the battery pack assembly are connected to the battery system;

[0089] S122, obtaining the output voltage and value of the remaining battery packs in the battery pack assembly;

[0090] S123, determining whether the output voltage and value are within a preset voltage range, if so, executing step S124, if not, executing step S125;

[0091] S124, confirming that the battery pack assembly is in a first fault state;

[0092] S125, determining whether the output voltage and value are zero, if yes, executing step S126, if no, executing step S127;

[0093] S126, confirming that the battery pack assembly is in a third fault state;

[0094] S127, confirm that the battery pack assembly is in the second fault state.

[0095] In this embodiment, the battery management module confirms the fault status of the battery pack assembly through the output voltage of the battery pack assembly.

[0096] S13, controlling the conduction states of the second switch and the third switch, and the working state of the voltage converter according to the fault state.

[0097] The implementation of this step may include the following steps:

[0098] S131, controlling the second switch to be turned on, the third switch to be turned off, or the first end and the third end of the third switch to be turned on and the voltage converter to be not working;

[0099] S132, controlling the second switch to be disconnected, the first end of the third switch and the second end of the third switch to be connected, and the voltage converter to operate so that the battery pack assembly is discharged by boosting the voltage converter;

[0100] S133, controlling the first end and the third end of the third switch to be turned on, and the voltage converter to operate so that the battery of the vehicle supplies power to the steering motor of the vehicle through the voltage converter.

[0101] In this embodiment, step S121 first removes the faulty battery pack in the battery pack assembly, and connects the remaining normal battery packs in series, so as to accurately identify the fault state of the battery pack assembly and avoid misjudgment of the third fault state caused by the battery pack failure. The output voltage sum is the sum of the output voltages of the remaining battery packs connected in series after the faulty battery pack is removed, and the preset voltage range is the limit voltage range in which the electrical equipment can work. For example, the minimum working voltage is Umim, the maximum working voltage is Umax, and the output voltage sum of the remaining battery packs is within the range of (Umim, Umax), then it is confirmed that it is in the first fault state, and the fault is relatively minor. At this time, there is no need to control the voltage converter to access the circuit, and the battery pack assembly can normally supply power to the electrical equipment. If the output voltage sum of the remaining battery packs is not within the range of (Umim, Umax) and is not zero, it is confirmed that it is in the second fault state, there are many faulty battery packs, and the voltage converter needs to be connected to the circuit to avoid the battery pack assembly from being unable to work normally due to the removal of the faulty battery pack, so as to ensure the normal operation of the electrical equipment, and at the same time, the battery system does not need to set up a spare battery pack, saving costs. When it is confirmed that the output voltage and value of the remaining battery pack are zero, it is determined that the high-voltage abnormal power-off of the battery pack assembly is in the third fault state, and the battery is controlled to supply power to the steering motor through the voltage converter to achieve steering protection when the vehicle's high-voltage abnormal power-off occurs.

[0102] like Fig.11 As shown, the method further comprises the following steps:

[0103] S141, confirming the discharge power of the battery pack assembly according to the output voltage and value; controlling the speed and output torque of the motor according to the voltage and value and the discharge power, and outputting a first alarm message and remaining maximum mileage information.

[0104] In this step, when the battery pack assembly is in the first fault state, the vehicle enters the battery pack fault driving mode, and limits the output of the motor according to the voltage and value of the battery pack assembly and the discharge power to ensure the safety of the battery pack assembly and other electrical components of the vehicle, and outputs the first alarm information at the same time, which can remind the driver of the current vehicle fault. The alarm information can be text, voice, picture and impact, which is not limited by this application. In addition, based on the current remaining battery pack power information, the remaining maximum mileage of the current battery pack assembly is evaluated, which is convenient for the driver to reasonably arrange the remaining journey.

[0105] S142, confirming the discharge power of the battery pack assembly according to the output voltage of the voltage converter; controlling the speed and output torque of the motor according to the output voltage and the discharge power, and outputting a second alarm message and remaining maximum mileage information.

[0106] In this step, when the battery pack assembly is in the second fault state, the voltage converter access circuit boosts the voltage output by the battery pack assembly and outputs it, and controls the motor output according to the voltage boosted by the voltage converter to ensure the power safety of the battery pack assembly and other electrical components of the vehicle, and outputs the second alarm information at the same time, which can remind the driver of the current vehicle fault condition, wherein the alarm information can be text, voice, picture and impact, which is not limited by this application. In addition, based on the current remaining battery pack power information, the remaining maximum mileage of the current battery pack assembly is evaluated, so that the driver can reasonably arrange the remaining journey.

[0107] like Fig.11 As shown, according to the vehicle control method of the embodiment of the present disclosure, the method further includes:

[0108] S151, cyclically obtaining fault information of battery pack components;

[0109] S111, determining whether the battery pack assembly is faulty, if so, outputting a fault clearing signal, and executing step S152;

[0110] S152, controlling the first switch so that all battery packs in the battery pack assembly are connected to the battery system, the second switch is turned on, the third switch is turned off or the first end and the third end of the third switch are turned on and the voltage converter does not work.

[0111] In this embodiment, a battery pack failure occurs in the vehicle, and the vehicle is in a battery pack failure discharge state. For the safety of the power battery and to reduce misjudgment, the battery management module will continue to monitor the battery pack and enter the battery pack failure cycle judgment process S151. Detect the health of the battery pack. If there is further danger, the discharge will be stopped, and the driver will be reminded to pull over to ensure safety. If the battery pack returns to normal, the vehicle can be restarted, the shielded battery pack can be released, and the vehicle can resume normal driving. The battery pack failure driving mode is recoverable, but after the battery management module detects that the battery pack failure has been resolved, it can start to resume normal driving, reducing misjudgment of maintenance situations.

[0112] According to the vehicle control method disclosed in the present invention, when a battery pack assembly of a vehicle fails, different controls can be performed according to the fault level of the faulty battery pack to enable the vehicle to travel when the fault occurs and ensure driving safety.

[0113] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of this application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of this application.

[0114] In the description of this application, it should be understood that the terms "first", "second", "third", and "fourth" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", "third", and "fourth" may explicitly or implicitly include at least one of the features.

[0115] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0116] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0117] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A battery system, characterized in that: The battery system comprises: A battery pack assembly, the battery pack assembly comprising at least two battery packs connected in series, each of the battery packs comprising a battery cell and a first switch for short-circuiting the battery pack; a second switch, wherein a first end of the second switch is connected to a first end of the battery pack assembly, and a second end of the second switch is a first output end of the battery system; a voltage converter, wherein a first input end of the voltage converter is connected to a first end of the second switch, and a second input end of the voltage converter is connected to a second end of the battery pack assembly to form a second output end of the battery system, wherein the first output end and the second output end form an output end group of the battery system for connecting an electrical device; a third switch, wherein a first end of the third switch is connected to the first output end of the voltage converter, and a second end of the third switch is connected to the second end of the second switch; A battery connected to the second output terminal of the voltage converter; A unidirectional conductive element, wherein the unidirectional conductive element is arranged between the second switch and the first output terminal of the battery system, the positive electrode of the unidirectional conductive element is connected to the second end of the third switch, and the negative electrode of the unidirectional conductive element is connected to the third end of the third switch, wherein the electrical equipment is a steering motor.

2. The battery system according to claim 1, characterized in that: The battery system further comprises: A controller is configured to control the conduction states of the first switch, the second switch, and the third switch and the working state of the voltage converter according to the fault state of the battery pack assembly.

3. The battery system according to claim 2, characterized in that: The fault state of the battery pack assembly includes a no-fault state, a first fault state, a second fault state and a third fault state; When the battery pack assembly is in a non-fault state, the controller is configured to control the first switch so that all battery packs in the battery pack assembly are connected to the battery system, control the second switch to be turned on, control the first end and the third end of the third switch to be turned on and the voltage converter to be inoperative or control the third switch to be turned off; When the battery pack assembly is in a first fault state, the controller is configured to control the first switch corresponding to the faulty battery pack in the battery pack assembly to short-circuit the faulty battery pack, connect the remaining battery packs in the battery pack assembly to the battery system, control the second switch to be turned on, control the first end of the third switch to be turned on with the third end and the voltage converter not to work or control the third switch to be turned off; When the battery pack assembly is in a second fault state, the controller is configured to control the first switch corresponding to the faulty battery pack in the battery pack assembly to short-circuit the faulty battery pack, connect the remaining battery packs in the battery pack assembly to the battery system, control the second switch to be disconnected, and control the first end and the second end of the third switch to be connected and the voltage converter to work; When the battery pack assembly is in the third fault state, the controller is configured to control the first switch corresponding to the faulty battery pack in the battery pack assembly to short-circuit the faulty battery pack, and the remaining battery packs in the battery pack assembly are connected to the battery system, and the first end and the third end of the third switch are controlled to be conductive and the voltage converter is operated.

4. The battery system according to any one of claims 1 to 3, characterized in that: The first switch is a single-pole double-throw switch, the positive electrode of the battery pack is the first end of the first switch, the second end of the first switch is connected to the positive electrode of the battery unit, the third end of the first switch is connected to the negative electrode of the battery unit to form the negative electrode of the battery pack, the battery pack assembly is formed by connecting the battery packs in series, and the first end and the second end of the first switch are in a normally-on state; or; The first switch is connected in parallel with the battery cell, the positive electrode of the battery cell is the positive electrode of the battery pack, the negative electrode of the battery cell is the negative electrode of the battery pack, and the first switch is in a normally-off state.

5. A vehicle, characterized in that: The vehicle is provided with a battery system as claimed in any one of claims 1 to 4 6. A vehicle control method, applied to the vehicle according to claim 5, characterized in that: Obtain fault information of battery pack components; Controlling the first switch according to the fault information and determining the fault state of the battery pack assembly; The conduction states of the second switch and the third switch and the working state of the voltage converter are controlled according to the fault state, wherein the fault information includes fault information of the battery pack in the battery pack assembly.

7. The control method according to claim 6, characterized in that: The controlling the first switch according to the fault information and determining the fault state of the battery pack assembly includes: According to the fault information of the battery pack in the battery pack assembly, controlling the first switch corresponding to the faulty battery pack in the battery pack assembly so that the first switch corresponding to the faulty battery pack short-circuits the faulty battery pack, and the remaining battery packs in the battery pack assembly are connected to the battery system; Get the output voltage and value of the remaining battery packs in the battery pack assembly; Determining whether the output voltage and value are within a preset voltage range; If yes, it is confirmed that the battery pack assembly is in the first fault state; If not, determining whether the output voltage and value are zero; If not, it is confirmed that the battery pack assembly is in the second fault state; If so, it is confirmed that the battery pack assembly is in the third fault state.

8. The control method according to claim 6, characterized in that: The controlling the conduction state of the second switch and the third switch and the working state of the voltage converter according to the fault state includes: If it is confirmed that the battery pack assembly is in the first fault state, the second switch is controlled to be turned on, the third switch is turned off, or the first end and the third end of the third switch are connected and the voltage converter does not work; If it is confirmed that the battery pack assembly is in the second fault state, the second switch is controlled to be disconnected, the first end of the third switch and the second end of the third switch are connected, and the voltage converter is operated so that the battery pack assembly is discharged by boosting the voltage through the voltage converter; If it is confirmed that the battery pack assembly is in the third fault state, the first end and the third end of the third switch are controlled to be turned on, and the voltage converter works so that the vehicle's battery supplies power to the vehicle's steering motor through the voltage converter.

9. The control method according to claim 7, characterized in that: If it is confirmed that the battery pack assembly is in the first fault state, the method further includes: confirming the discharge power of the battery pack assembly according to the output voltage and value; The rotation speed and output torque of the motor are controlled according to the voltage and value and the discharge power, and the first alarm information and the remaining maximum mileage information are output.

10. The control method according to claim 7, characterized in that: If it is confirmed that the battery pack assembly is in the second fault state, the method further includes: Determining the discharge power of the battery pack assembly according to the output voltage of the voltage converter; The rotation speed and output torque of the motor are controlled according to the output voltage and the discharge power, and a second alarm message and remaining maximum mileage information are output.

11. The control method according to any one of claims 6 to 10, characterized in that: The method further comprises: Circularly obtain the fault information of battery pack components; Determine whether the battery pack components are faulty; If not, a fault relief signal is output, and the first switch is controlled so that all battery packs in the battery pack assembly are connected to the battery system, the second switch is turned on, the third switch is turned off or the first end and the third end of the third switch are turned on and the voltage converter does not work.

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