A dual-battery power supply system for electric vehicle and control method thereof

Abstract

The embodiment of the present invention discloses a dual-battery power supply system for an electric vehicle and a control method thereof, wherein the dual-battery power supply system comprises: an electrically connected first battery assembly and a second battery assembly, wherein the first battery assembly comprises an electrically connected first battery management system and a first battery, and the second battery assembly comprises an electrically connected second battery management system and a second battery; the first battery management system is used to collect electrical parameters of the first battery; the second battery management system is used to collect electrical parameters of the second battery, and according to the electrical parameters of the first battery and the second battery, switch to a single-battery power supply mode or a dual-battery power supply mode. The embodiment of the present invention can provide the entire vehicle with the maximum power supply power and system power supply backup, improve the driving safety and stability while increasing the cruising range, and improve the riding experience of the user. In addition, the dual-battery power supply system reduces the volume of a single battery assembly and is easy to carry.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of battery control technology, and in particular to a dual-battery power supply system for an electric vehicle and a control method thereof. Background Art

[0002] With the advancement of science and technology and the development of society, electric vehicles are loved by people as a new energy green environmental protection product. Electric vehicles are a kind of transportation vehicle that uses batteries as energy, and batteries are one of the most important components of electric vehicles.

[0003] As the market and user groups continue to increase their requirements for driving range and motor power, single-battery systems can no longer meet the demand. The existing single-battery system for electric vehicles has the problem of short driving range, which easily leads to users' mileage anxiety and brings a bad riding experience. Since there is only one battery for power supply, there is no replacement battery when the power supply battery fails, which affects the safety and stability of driving. In addition, in order to extend the driving range, the single battery is large in size and inconvenient to carry. Summary of the invention

[0004] The embodiment of the present invention provides an electric vehicle dual-battery power supply system and a control method thereof, so as to solve the problems of a single-battery system having a short battery life, no replacement battery, and being inconvenient to carry.

[0005] An embodiment of the present invention provides a dual-battery power supply system for an electric vehicle, the system comprising: a first battery assembly and a second battery assembly that are electrically connected, the first battery assembly comprising a first battery management system and a first battery that are electrically connected, the second battery assembly comprising a second battery management system and a second battery that are electrically connected;

[0006] The first battery management system is used to collect electrical parameters of the first battery;

[0007] The second battery management system is used to collect electrical parameters of the second battery, and obtain the electrical parameters of the first battery through the first battery management system, and switch to a target power supply mode according to the electrical parameters of the first battery and the electrical parameters of the second battery, and the target power supply mode is a single-battery power supply mode or a dual-battery power supply mode.

[0008] Further, the electrical parameters include at least a supply voltage;

[0009] The second battery management system is used to determine that the open circuit voltages of the first battery and the second battery are consistent and switch to the dual-battery power supply mode when it is detected that the supply voltages of the first battery and the second battery are consistent, or to determine that the open circuit voltages of the first battery and the second battery are inconsistent and switch to the single-battery power supply mode when it is detected that the supply voltages of the first battery and the second battery are inconsistent.

[0010] Furthermore, the electrical parameters also include discharge current;

[0011] The second battery management system is used to determine that the open circuit voltages of the first battery and the second battery are consistent when it is detected that the difference in the discharge current ratio of the first battery and the second battery is within a preset range, or to determine that the open circuit voltages of the first battery and the second battery are inconsistent when it is detected that the difference in the discharge current ratio of the first battery and the second battery exceeds the preset range.

[0012] Further, the battery assembly includes a discharge circuit and a charging circuit;

[0013] The second battery management system is used to control the discharge circuit and the charging circuit of each battery assembly to be opened when switching to the dual-battery power supply mode, so as to perform dual-battery parallel power supply;

[0014] The second battery management system is used to control the discharge circuit and the charging circuit of the target battery assembly to be opened, and the discharge circuit and the charging circuit of another battery assembly to be closed when switching to the single battery power supply mode, so as to perform single battery power supply.

[0015] Further, the electrical parameters include electrical quantity;

[0016] The power of the target battery assembly is greater than the power of another battery assembly in an open circuit state.

[0017] Furthermore, after the second battery management system switches to the single battery power supply mode, if it is detected that the power level of the battery component in the power supply state is lower than the power level of the battery component in the open circuit state, or if it is detected that the battery component in the power supply state fails, it controls to open the discharge circuit of the battery component in the open circuit state, then closes the discharge circuit and charging circuit of the battery component in the power supply state, and finally opens the charging circuit of the battery component in the open circuit state.

[0018] Furthermore, the second battery management system is used to open the power output path of another battery assembly and cut off the power output path of the faulty battery when a fault is detected in any battery assembly.

[0019] Furthermore, the electric vehicle dual-battery power supply system also includes: when powering on, the second battery management system is used to control the second battery to power on the electric vehicle and wake up the first battery assembly; or, when powering on, the second battery management system is used to control the first battery to power on the electric vehicle when it determines that the second battery is in a low-power state.

[0020] Furthermore, the electric vehicle dual-battery power supply system also includes: after power-on is completed, the second battery management system sends a power supply limit power and the electrical parameters to the entire vehicle system according to the target power supply mode of the current dual-battery power supply system, and the entire vehicle system adjusts the power consumption of the entire vehicle according to the electrical parameters.

[0021] Based on the same inventive concept, an embodiment of the present invention further provides a control method for the dual-battery power supply system of an electric vehicle as described above, wherein the dual-battery power supply system of an electric vehicle comprises: a first battery assembly and a second battery assembly that are electrically connected, wherein the first battery assembly comprises a first battery management system and a first battery that are electrically connected, and the second battery assembly comprises a second battery management system and a second battery that are electrically connected;

[0022] The control method includes:

[0023] The first battery management system collects electrical parameters of the first battery;

[0024] The second battery management system collects electrical parameters of the second battery, and obtains the electrical parameters of the first battery through the first battery management system, and switches to a target power supply mode according to the electrical parameters of the first battery and the electrical parameters of the second battery, and the target power supply mode is a single-battery power supply mode or a dual-battery power supply mode.

[0025] The electric vehicle dual-battery power supply system provided by the embodiment of the present invention includes an electrically connected first battery assembly and a second battery assembly, the first battery assembly includes an electrically connected first battery management system and a first battery, and the second battery assembly includes an electrically connected second battery management system and a second battery; the electrical parameters of the first battery and the second battery are respectively collected through the first battery management system and the second battery management system, and the electrical parameters of the first battery are obtained through the first battery management system by using the second battery management system, and the target power supply mode is switched to a single battery power supply mode or a dual battery power supply mode according to the electrical parameters of the first battery and the second battery. The electric vehicle dual-battery power supply system provided by the embodiment of the present invention can automatically switch the target power supply mode according to the electrical parameters of the battery assembly, provide the maximum power supply power and system power backup for the whole vehicle, improve the driving safety and stability while improving the cruising range, and improve the riding experience of the user. In addition, the dual-battery power supply system splits a battery pack into two battery assemblies, reduces the volume of a single battery assembly, and is easy to carry. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, although the drawings described below are some specific embodiments of the present invention, for those skilled in the art, the basic concepts of the device structure, driving method and manufacturing method disclosed and suggested by the various embodiments of the present invention can be expanded and extended to other structures and drawings, and there is no doubt that these should be within the scope of the claims of the present invention.

[0027] Figure 1 It is a structural schematic diagram of a dual-battery power supply system for an electric vehicle provided by an embodiment of the present invention;

[0028] Figure 2 The present invention provides a flow chart of a control method of a dual-battery power supply system for an electric vehicle. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described through implementation methods with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the basic concepts disclosed and suggested by the embodiments of the present invention, all other embodiments obtained by those skilled in the art are within the scope of protection of the present invention.

[0030] Figure 1 It is a structural schematic diagram of a dual-battery power supply system for an electric vehicle provided in an embodiment of the present invention. The technical solution of this embodiment is applicable to the situation where a dual-battery power supply system is used to power an electric vehicle. The system can be implemented by software and / or hardware and can be integrated into an electric vehicle.

[0031] like Figure 1 As shown, the electric vehicle dual-battery power supply system provided by this embodiment includes: an electrically connected first battery assembly 100 and a second battery assembly 200, the first battery assembly 100 includes an electrically connected first battery management system 110 and a first battery 120, and the second battery assembly 200 includes an electrically connected second battery management system 210 and a second battery 220; the first battery management system 110 is used to collect electrical parameters of the first battery 120; the second battery management system 210 is used to collect electrical parameters of the second battery 220, and obtain the electrical parameters of the first battery 120 through the first battery management system 110, and switch to the target power supply mode according to the electrical parameters of the first battery 120 and the electrical parameters of the second battery 220, and the target power supply mode is a single battery power supply mode or a dual battery power supply mode.

[0032] The electric vehicle dual battery power supply system provided in this embodiment includes a first battery assembly 100 and a second battery assembly 200 that are electrically connected. Each battery assembly is composed of a battery management system and a battery. The battery management system is used to collect electrical parameters of the battery electrically connected thereto, and the battery is used to power the electric vehicle. Specifically, the first battery assembly 100 includes a first battery management system 110 and a first battery 120, and the second battery assembly 200 includes a second battery management system 210 and a second battery 220. The first battery management system 110 is used to collect electrical parameters of the first battery 120, and the second battery management system 210 is used to collect electrical parameters of the second battery 220.

[0033] The first battery assembly 100 and the second battery assembly 200 respectively exchange data through the existing internal battery management systems, namely the first battery management system 110 and the second battery management system 210, without the need for additional battery control units, which can simplify the system structure and reduce costs. The second battery assembly 200 controls the entire battery power supply system through the internal second battery management system 210. Specifically, electrical parameters may include information such as the battery supply voltage, current, power, power, and temperature. The first battery assembly 100 and the second battery assembly 200 also obtain each other's electrical parameters through the first battery management system 110 and the second battery management system 210, respectively, to understand each other's power and fault status information, so as to optimize the power supply interaction of the dual battery power supply system.

[0034] The first battery management system 110 obtains the electrical parameters of the second battery 220 through the second battery management system 210. When it is detected that the electrical parameters of the second battery 220 are out of the normal range, the second battery assembly 200 is determined to be faulty, and when it does not obey the dispatch of the second battery management system 210 and determines that it is faulty according to its own electrical parameters, it promptly feeds back to the second battery management system 210 through the first battery management system 110. The second battery management system 210 obtains the electrical parameters of the first battery 120 through the first battery management system 110, and switches to the target power supply mode of the single battery power supply mode or the dual battery power supply mode according to the electrical parameters of the first battery 120 and the electrical parameters of the second battery 220.

[0035] When the dual-battery power supply system allows for appropriate conditions, such as when both battery packs are fully charged and both are fault-free, it will switch to the dual-battery power supply mode in a timely manner to provide greater power supply and system power backup for the entire vehicle, thereby increasing the range while ensuring the riding safety and riding experience of the user. In addition, by splitting a battery pack into two, each battery pack is relatively small and easy to carry.

[0036] The communication method between the first battery assembly 100 and the second battery assembly 200 is not limited, and data exchange can be performed through CAN communication. The method for determining that the second battery management system 210 is the control unit of the entire battery system is not limited. For example, the first battery management system 210 and the second battery management system 220 can determine that the second battery assembly 200 is the control unit of the entire battery system by identifying the signal line added outside the second battery assembly 200.

[0037] The electric vehicle dual-battery power supply system provided by the embodiment of the present invention includes an electrically connected first battery assembly and a second battery assembly, the first battery assembly includes an electrically connected first battery management system and a first battery, and the second battery assembly includes an electrically connected second battery management system and a second battery; the electrical parameters of the first battery and the second battery are respectively collected through the first battery management system and the second battery management system, and the electrical parameters of the first battery are obtained through the first battery management system by using the second battery management system, and the target power supply mode is switched to a single battery power supply mode or a dual battery power supply mode according to the electrical parameters of the first battery and the second battery. The electric vehicle dual-battery power supply system provided by the embodiment of the present invention can automatically switch the target power supply mode according to the electrical parameters of the battery assembly, provide the maximum power supply power and system power backup for the whole vehicle, improve the driving safety and stability while improving the cruising range, and improve the riding experience of the user. In addition, the dual-battery power supply system splits a battery pack into two battery assemblies, reduces the volume of a single battery assembly, and is easy to carry.

[0038] Optionally, the electric vehicle dual battery power supply system also includes: when powering on, the second battery management system 210 is used to control the second battery 220 to power on the electric vehicle and wake up the first battery assembly 100; or, when powering on, the second battery management system 210 is used to control the first battery 120 to power on the electric vehicle when it determines that the second battery 220 is in a low-power state.

[0039] like Figure 1 As shown, after the battery is connected, the second battery management system 210 preferentially controls the second battery 220 to power on the electric vehicle, and wakes up the first battery assembly 100 through a signal, and obtains the electrical parameters of the first battery assembly 100 through CAN communication and other methods. If the second battery management system 210 determines that the second battery 220 is in a low-power state and cannot power on the electric vehicle based on the electrical parameters of the second battery 220, the second battery management system 210 wakes up the first battery assembly 100 through a signal, obtains the electrical parameters of the first battery assembly 100, and controls the first battery 120 to power on the electric vehicle when it is confirmed that the power supply of the first battery assembly 100 is normal based on the electrical parameters.

[0040] Optionally, the electrical parameters include at least the power supply voltage; the second battery management system 210 is used to determine that the open circuit voltages of the first battery 120 and the second battery 220 are consistent when it detects that the power supply voltages of the first battery 120 and the second battery 220 are consistent, and switch to the dual-battery power supply mode; or, when it detects that the power supply voltages of the first battery 120 and the second battery 220 are inconsistent, determine that the open circuit voltages of the first battery 120 and the second battery 220 are inconsistent, and switch to the single-battery power supply mode.

[0041] like Figure 1 As shown, after the electric vehicle is powered on, the second battery management system 210 determines whether the open circuit voltages of the first battery 120 and the second battery 220 are consistent based on the electrical parameters of the acquired battery assembly. If it is detected that the power supply voltages of the two are consistent, it is determined that the open circuit voltages of the first battery 120 and the second battery 220 are consistent, and the dual battery power supply mode is switched. If the second battery management system 210 detects that the power supply voltages of the first battery 120 and the second battery 220 are inconsistent, it is determined that the open circuit voltages of the first battery 120 and the second battery 220 are inconsistent, and the single battery power supply mode is switched to use a battery assembly with a high power supply voltage to power the electric vehicle, providing the best power supply and riding power for the entire vehicle. When two battery assemblies with different open circuit voltages are powered in parallel, the high-voltage battery assembly will charge the low-voltage battery assembly, and a short circuit fault will be falsely reported. Whether the open circuit voltages of the two battery assemblies are consistent is indirectly judged based on electrical parameters such as the power supply voltage. When the open circuit voltages of the two battery assemblies are determined to be consistent, that is, when the power supply platforms of the two battery assemblies are consistent, the dual-battery power supply mode is adopted. When the open circuit voltages are inconsistent, the single-battery power supply mode with a high power supply voltage is adopted, which can ensure the user's riding safety and improve the riding experience.

[0042] Optionally, the electrical parameters also include discharge current; the second battery management system 210 is used to determine that the open circuit voltages of the first battery 120 and the second battery 220 are consistent when it is detected that the ratio difference of the discharge currents of the first battery 120 and the second battery 220 is within a preset range, or to determine that the open circuit voltages of the first battery 120 and the second battery 220 are inconsistent when it is detected that the ratio difference of the discharge currents of the first battery 120 and the second battery 220 exceeds a preset range.

[0043] like Figure 1As shown, the second battery management system 210 can determine whether the open circuit voltages of the two battery assemblies are consistent by the supply voltage in the electrical parameters, and can also further determine whether the open circuit voltages of the two battery assemblies are consistent by detecting whether the difference in the discharge current ratio of the two battery assemblies is within a preset range. Specifically, when the second battery management system 210 detects that the difference in the discharge current ratio of the first battery 120 and the second battery 220 is within a preset range, it determines that the open circuit voltages of the first battery 120 and the second battery 220 are consistent, and switches to a dual-battery power supply mode; when it detects that the difference in the discharge current ratio of the first battery 120 and the second battery 220 exceeds the preset range, it determines that the open circuit voltages of the first battery 120 and the second battery 220 are inconsistent, and switches to a single-battery power supply mode to avoid mutual charging short circuit. Among them, the preset range of the discharge current ratio difference is not limited and can be set according to the actual situation of the battery. For example, the preset range can be set to the absolute value of the discharge current difference of the two battery assemblies divided by the average value.

[0044] Due to the influence of the internal resistance of the battery, the voltage of the battery assembly in the power supply state and the battery assembly in the open circuit state of the two battery assemblies cannot be completely consistent, so it is not possible to accurately judge whether the open circuit voltages of the two battery assemblies are consistent based only on the power supply voltage of the two battery assemblies. If the open circuit voltages of the two battery assemblies are very close, the difference in their discharge currents will not be too large and will be within a certain range, that is, the preset range. By further judging whether their open circuit voltages are consistent based on the difference in the discharge current ratio of the two battery assemblies, it is more practical and can improve the accuracy of the judgment.

[0045] The second battery management system 210 can re-detect the supply voltage and / or discharge current ratio difference of the two battery assemblies at certain intervals. When it is detected that the supply voltages of the two battery assemblies are consistent and / or the discharge current ratio difference is within a preset range, it switches to a dual-battery power supply mode for parallel power supply, thereby optimizing the power supply solution and providing the best power supply and a better riding experience for the electric vehicle.

[0046] Optionally, the battery assembly includes a discharge circuit and a charging circuit; the second battery management system is used to control the discharge circuit and the charging circuit of each battery assembly to be turned on when switching to the dual-battery power supply mode, so as to provide dual-battery parallel power supply; the second battery management system is used to control the discharge circuit and the charging circuit of the target battery assembly to be turned on, and the discharge circuit and the charging circuit of the other battery assembly to be turned off when switching to the single-battery power supply mode, so as to provide single-battery power supply.

[0047] Both battery assemblies include a discharge circuit and a charging circuit. When the discharge circuit of the battery assembly is turned on, it can supply power to the entire vehicle. In situations such as braking or going downhill, the motor control module and other components in the electric vehicle can reversely charge the battery assembly through the charging circuit to increase the driving range, so the charging circuit needs to be turned on during riding. In the dual-battery power supply mode, the second battery management system controls the opening of the discharge circuit and the charging circuit of the two battery assemblies to supply power to the dual batteries in parallel; in the single-battery power supply mode, the second battery management system controls the opening of the discharge circuit and the charging circuit of the high-voltage target battery assembly, and closes the discharge circuit and the charging circuit of the other low-voltage battery assembly to supply power to a single battery, preventing the two battery assemblies from supplying power in parallel and causing a short circuit, while providing the best power supply for the electric vehicle.

[0048] Optionally, the electrical parameter includes power; the power of the target battery component is greater than the power of another battery component in an open circuit state.

[0049] In the single-battery power supply mode, the second battery management system controls the opening of the discharge circuit and the charging circuit of the target battery assembly with high power, and closes the discharge circuit and the charging circuit of another low-power battery assembly to supply power to the single battery, thereby providing the best power supply and riding power for the entire vehicle and improving the user's riding experience.

[0050] Optionally, after the second battery management system switches to the single-battery power supply mode, if it detects that the power level of the battery component in the power supply state is lower than the power level of the battery component in the open-circuit state, or if it detects that the battery component in the power supply state has a fault, it controls the opening of the discharge circuit of the battery component in the open-circuit state, then closes the discharge circuit and charging circuit of the battery component in the power supply state, and finally opens the charging circuit of the battery component in the open-circuit state.

[0051] In the single-battery power supply mode, after a period of continuous power supply, the power of the battery assembly in the power supply state may be significantly lower than the power of the battery assembly in the open circuit state, affecting the user's riding experience, or when the battery assembly in the power supply state fails, the riding will be affected. When the second battery management system detects the above situation, it first controls the discharge circuit of the battery assembly in the open circuit state to power the electric vehicle, then closes the discharge circuit and charging circuit of the battery assembly in the power supply state, and finally opens the charging circuit of the battery assembly in the open circuit state. That is, the second battery management system monitors the power and fault status of the two battery assemblies in real time, and adjusts the power supply strategy to ensure the power supply of the high-power battery assembly in the single-battery power supply mode and optimize the power supply plan. In addition, the closing or opening sequence of the charging circuit and the discharging circuit of the above two battery assemblies can enable the two battery assemblies to switch power smoothly without sudden power outages or unstable power supply.

[0052] Optionally, the second battery management system is used to open the power output path of another battery assembly and cut off the power output path of the faulty battery when a fault is detected in any battery assembly.

[0053] When the second battery management system detects that one of the two battery assemblies is faulty, it switches on the power supply output path of the other battery assembly to supply power to the electric vehicle, so that the battery assembly without the fault problem continues to supply power, and promptly cuts off the power supply output path of the faulty battery assembly, so that the riding speed will slowly drop, and there will be no sudden power outage or unstable power supply. The dual-battery power supply system provided in this embodiment can automatically switch the power supply mode according to the state of the battery assembly, select the dual-battery power supply mode or the single-battery power supply mode, and can switch smoothly without power failure, which can improve riding safety and user experience.

[0054] Optionally, the electric vehicle dual battery power supply system also includes: after power-on is completed, the second battery management system sends a power supply limit power and electrical parameters to the entire vehicle system according to the target power supply mode of the current dual battery power supply system, and the entire vehicle system adjusts the power consumption of the entire vehicle according to the electrical parameters.

[0055] After power-on is completed, the second battery management system can send the corresponding power supply limit power and the electrical parameters of the battery assembly to the vehicle system through CAN communication according to the target power supply mode of the current dual-battery power supply system. The various components of the vehicle system obtain the electrical parameters and adjust the power consumption of the vehicle according to their own functions. Among them, the power supply limit power corresponding to the target power supply mode is not limited and can be set according to the actual situation of the battery assembly. The implementation method of the vehicle system adjusting the power consumption of the vehicle according to the electrical parameters is not limited. For example, if the electrical parameters of the battery assembly include voltage, current, power, power and temperature, the central control module in the vehicle system can adjust the power consumption mode of the vehicle according to the electrical parameters. For example, if the battery assembly is insufficient or in a single-battery power supply mode, the central control module controls the vehicle to switch to energy-saving mode. If the battery assembly is sufficient or in a dual-battery power supply mode, the central control module controls the vehicle to switch to sports mode. The motor controller in the vehicle system can adjust the acceleration performance, climbing performance, and riding upper limit speed of the vehicle according to the electrical parameters. The motor controller in the vehicle system can reduce the power of the vehicle to reduce the temperature of the battery components and protect the battery components based on the temperature information when judging that the battery components have abnormal temperature. The second battery management system sends the power supply limit power and electrical parameters to the vehicle system according to the target power supply mode of the current dual-battery power supply system, and supplies power to the vehicle with the optimal power to ensure driving safety and riding stability.

[0056] Figure 2This is a flow chart of a control method for a dual-battery power supply system for an electric vehicle provided by an embodiment of the present invention. The technical solution of this embodiment is applicable to the case where a dual-battery power supply system is used to power an electric vehicle. This method can be executed by a dual-battery power supply system for an electric vehicle provided by any embodiment of the present invention. The system can be implemented by software and / or hardware and can be integrated into an electric vehicle.

[0057] The electric vehicle dual-battery power supply system provided in this embodiment includes: a first battery assembly and a second battery assembly that are electrically connected, the first battery assembly includes a first battery management system and a first battery that are electrically connected, and the second battery assembly includes a second battery management system and a second battery that are electrically connected;

[0058] The control method includes:

[0059] S100: A first battery management system collects electrical parameters of a first battery.

[0060] S200, the second battery management system collects electrical parameters of the second battery, and obtains electrical parameters of the first battery through the first battery management system, and switches to a target power supply mode according to the electrical parameters of the first battery and the electrical parameters of the second battery, where the target power supply mode is a single-battery power supply mode or a dual-battery power supply mode.

[0061] The control method of the electric vehicle dual-battery power supply system provided in this embodiment has the corresponding functional modules of the electric vehicle dual-battery power supply system provided in any embodiment of the present invention.

[0062] The electric vehicle dual-battery power supply system provided by the embodiment of the present invention comprises an electrically connected first battery assembly and a second battery assembly, wherein the first battery assembly comprises an electrically connected first battery management system and a first battery, and the second battery assembly comprises an electrically connected second battery management system and a second battery. The control method of the electric vehicle dual-battery power supply system provided by the embodiment of the present invention collects the electrical parameters of the first battery and the second battery respectively through the first battery management system and the second battery management system, and uses the second battery management system to obtain the electrical parameters of the first battery through the first battery management system, and switches to the target power supply mode of the single battery power supply mode or the dual battery power supply mode according to the electrical parameters of the first battery and the second battery. The control method can automatically switch the target power supply mode according to the electrical parameters of the battery assembly, provide the maximum power supply power and system power supply backup for the whole vehicle, improve the driving safety and stability while improving the cruising range, and improve the riding experience of the user. In addition, the dual-battery power supply system splits a battery pack into two battery assemblies, reduces the volume of a single battery assembly, and is easy to carry.

[0063] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An electric vehicle dual battery power supply system, characterized in that: include: an electrically connected first battery assembly and a second battery assembly, the first battery assembly comprising an electrically connected first battery management system and a first battery, the second battery assembly comprising an electrically connected second battery management system and a second battery; The first battery management system is used to collect electrical parameters of the first battery; The second battery management system is used to collect electrical parameters of the second battery, and obtain the electrical parameters of the first battery through the first battery management system, and switch to a target power supply mode according to the electrical parameters of the first battery and the electrical parameters of the second battery, where the target power supply mode is a single-battery power supply mode or a dual-battery power supply mode; The electrical parameters include at least the supply voltage; The second battery management system is used to determine that the open circuit voltages of the first battery and the second battery are consistent when it is detected that the supply voltages of the first battery and the second battery are consistent, and switch to the dual-battery power supply mode; or, when it is detected that the supply voltages of the first battery and the second battery are inconsistent, determine that the open circuit voltages of the first battery and the second battery are inconsistent, and switch to the single-battery power supply mode; The electrical parameters also include discharge current; The second battery management system is used to determine that the open circuit voltages of the first battery and the second battery are consistent when it is detected that the difference in the discharge current ratio of the first battery and the second battery is within a preset range, or to determine that the open circuit voltages of the first battery and the second battery are inconsistent when it is detected that the difference in the discharge current ratio of the first battery and the second battery exceeds the preset range; The battery assembly includes a discharge circuit and a charging circuit; The second battery management system is used to control the discharge circuit and the charging circuit of each battery assembly to be opened when switching to the dual-battery power supply mode, so as to perform dual-battery parallel power supply; The second battery management system is used to control the discharge circuit and the charging circuit of the target battery assembly to be opened, and the discharge circuit and the charging circuit of another battery assembly to be closed when switching to the single battery power supply mode, so as to perform single battery power supply.

2. The electric vehicle dual battery power supply system according to claim 1, characterized in that: The electrical parameters include electrical quantity; The power of the target battery assembly is greater than the power of another battery assembly in an open circuit state.

3. The electric vehicle dual battery power supply system according to claim 2, characterized in that: After the second battery management system switches to the single battery power supply mode, if it is detected that the power of the battery component in the power supply state is lower than the power of the battery component in the open circuit state, or if it is detected that the battery component in the power supply state fails, it controls to open the discharge circuit of the battery component in the open circuit state, then closes the discharge circuit and the charging circuit of the battery component in the power supply state, and finally opens the charging circuit of the battery component in the open circuit state.

4. The electric vehicle dual battery power supply system according to claim 1, characterized in that: The second battery management system is used to conduct the power output path of another battery assembly and cut off the power output path of the faulty battery when a fault is detected in any battery assembly.

5. The electric vehicle dual battery power supply system according to claim 1, characterized in that: The electric vehicle dual-battery power supply system also includes: when power is turned on, the second battery management system is used to control the second battery to power on the electric vehicle and wake up the first battery component; or, when power is turned on, the second battery management system is used to control the first battery to power on the electric vehicle when it determines that the second battery is in a low-power state.

6. The electric vehicle dual battery power supply system according to claim 1, characterized in that: The electric vehicle dual-battery power supply system also includes: after power-on is completed, the second battery management system sends a power supply limit power and the electrical parameters to the entire vehicle system according to the target power supply mode of the current dual-battery power supply system, and the entire vehicle system adjusts the power consumption of the entire vehicle according to the electrical parameters.

7. A control method for a dual battery power supply system for an electric vehicle as claimed in any one of claims 1 to 6, characterized in that: The electric vehicle dual-battery power supply system comprises: a first battery assembly and a second battery assembly which are electrically connected, wherein the first battery assembly comprises a first battery management system and a first battery which are electrically connected, and the second battery assembly comprises a second battery management system and a second battery which are electrically connected; The control method includes: The first battery management system collects electrical parameters of the first battery; The second battery management system collects electrical parameters of the second battery, and obtains the electrical parameters of the first battery through the first battery management system, and switches to a target power supply mode according to the electrical parameters of the first battery and the electrical parameters of the second battery, and the target power supply mode is a single-battery power supply mode or a dual-battery power supply mode.

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