Multi-battery control system and electric vehicle

Abstract

To provide a multi-battery control system and an electric vehicle in which a main battery manages an auxiliary battery.SOLUTION: In a multi-battery control system of an electric-assisted bicycle, a main battery module includes a main controller that controls a main battery so as to supply current to a motor module 20 of the electric-assisted bicycle and acquires a first state of charge (SoC) value of the main battery and a first battery temperature, and an auxiliary battery module having an auxiliary controller and an auxiliary battery. The main controller controls the auxiliary battery module by using a communication interface and communicating with the auxiliary controller. The auxiliary battery module selectively supplies the current to the motor module or charges the main battery, and the main controller also obtains a second SoC value of the auxiliary battery and a second battery temperature via the communication interface.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of U.S. Provisional Application No. 63 / 458,663, filed April 12, 2023, the contents of which are incorporated herein by reference.

[0002] The present invention relates to a multi-battery control system and an electric vehicle, and more particularly to a multi-battery control system and an electric vehicle in which a main battery manages an auxiliary battery. [Background technology]

[0003] As electric vehicles become more popular, the application of lightweight electric vehicles, such as electric assist bicycles, electric motorcycles, electric wheelchairs, and golf carts, has also become important. Currently, the development and durability of lightweight electric vehicles are limited by battery capacity, so increasing capacity requires connecting more batteries in parallel. For example, a lightweight electric vehicle may be equipped with a main battery and one or more auxiliary batteries to increase durability. Furthermore, to simplify the wiring of a lightweight electric vehicle, the auxiliary battery may be connected only to the main battery, which then communicates with the motor controller and manages the other auxiliary batteries.

[0004] Therefore, how to manage the power of the main battery and the auxiliary battery has become one of the goals of the industry. Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, an object of the present invention is to provide a multi-battery control system and an electric vehicle that solves the above problems. [Means for solving the problem]

[0006] An embodiment of the present invention discloses a multi-battery control system for use in an electric vehicle, the multi-battery control system including: a main battery module including a main controller and a main battery, wherein the main controller controls the main battery to supply current to a motor module of the electric vehicle, and the main controller acquires a first state of charge (SoC) value and a first battery temperature of the main battery; and an auxiliary battery module including an auxiliary controller and an auxiliary battery, wherein the main controller controls the auxiliary battery module by communicating with the auxiliary controller using a communication interface, the auxiliary battery module selectively supplies current to the motor module or charges the main battery, and the main controller acquires a second SoC value and a second battery temperature of the auxiliary battery via the communication interface.

[0007] An embodiment of the present invention discloses an electric vehicle, the electric vehicle comprising: a motor module including a motor and a motor controller, wherein the motor controller controls the motor to drive and move the electric vehicle; a main battery module including a main controller and a main battery, wherein the main controller controls the main battery to supply current to the motor by communicating with the motor controller using a first communication interface, and the main controller obtains a first state of charge (SoC) value and a first battery temperature of the main battery; and an auxiliary battery module including an auxiliary controller and an auxiliary battery, wherein the main controller controls the auxiliary battery module by communicating with the auxiliary controller using a second communication interface, and the auxiliary battery module selectively supplies current to the motor module or charges the main battery, and the main controller obtains a second SoC value and a second battery temperature of the auxiliary battery via the communication interface.

[0008] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. [Brief explanation of the drawings]

[0009] [Figure 1A] 1 is a schematic diagram of a multi-battery control system according to an embodiment of the present invention; [Figure 1B] 1 is a schematic diagram of an electrically assisted bicycle according to an embodiment of the present invention; [Figure 2] 3 is a flowchart of a discharge control method according to an embodiment of the present invention. [Figure 3] 4 is a flowchart of a discharge mode of the multi-battery control system according to one embodiment of the present invention. [Figure 4] 10 is a flowchart of a discharge mode of a multi-battery control system according to another embodiment of the present invention. [Figure 5] 10 is a flowchart of a discharge mode of a multi-battery control system according to another embodiment of the present invention. [Figure 6] 3 is a flowchart of a charge control method according to an embodiment of the present invention. [Figure 7] 4 is a flowchart of a charging mode of the multi-battery control system according to one embodiment of the present invention. [Figure 8] 10 is a flowchart of a charging mode of a multi-battery control system according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Certain terms are used throughout the description and the following claims to refer to particular components. As one skilled in the art will appreciate, hardware manufacturers may refer to components by different names. This document does not intend to distinguish between components that differ in name but not function. In the following description and claims, the terms "include" and "comprise" are used in an open-ended manner and, therefore, should be interpreted to mean "including, but not limited to." Also, the term "couple" shall mean either an indirect or direct electrical connection. Thus, when a device is coupled to another device, the connection may be by a direct electrical connection or by an indirect electrical connection via other devices and connections.

[0011] 1A and 1B are schematic diagrams of a multi-battery control system 10 and an electric assist bicycle 1 according to an embodiment of the present invention. The multi-battery control system 10 includes a main battery module 12 and an auxiliary battery module 14. The multi-battery control system 10 can be installed at any position on the electric assist bicycle 1 to supply current to the motor module 20 of the electric assist bicycle 1. For example, the main battery module 12 can be installed on the down tube of the electric assist bicycle 1, the auxiliary battery module 14 can be installed in a water bottle cage of the electric assist bicycle 1, and the motor module 20 can be installed on the front wheel hub, rear wheel hub, front motor, rear motor, or mid-mounted motor of the central axis of the electric assist bicycle 1, but is not limited thereto. The multi-battery control system 10 of the present invention can also be applied to electric motorcycles, electric wheelchairs, golf carts, or other types of electric vehicles in addition to the electric assist bicycle 1. It should be noted that those skilled in the art can make appropriate adjustments according to system requirements.

[0012] 1A , the main battery module 12 includes a main controller 122 and a main battery 124. The auxiliary battery module 14 includes an auxiliary controller 142 and an auxiliary battery 144. The motor module 20 includes a motor controller 202 and a motor 204. The main controller 122 is coupled to the motor controller 202 and controls the main battery 124 to supply current to the motor 204. It should be noted that the motor 204 and the motor controller 202 of the motor module 20 may be integrated into one component or separated into two components. Furthermore, the main controller 122 is coupled to the auxiliary controller 142 to control the auxiliary battery module 14, whereby the auxiliary battery 144 selectively supplies current to the motor module 20 or charges the main battery 124. It should be noted that the main controller 122 communicates with the motor controller 202 using a first communication interface and with the auxiliary controller 142 using a second communication interface. For example, the first communication interface may be a universal asynchronous receiver / transmitter (UART), and the second communication interface may be a controller area network (CAN), but is not limited thereto. Note that vehicle communication protocols such as universal asynchronous transmitters and controller area networks are well known in the art and will not be repeated here. Furthermore, as shown in FIG. 1A, the multi-battery control system 10 can be coupled to a charging module 30 to enter a charging state and charge the main battery 124 and / or the auxiliary battery 144.

[0013] It should be noted that the main battery module 12 or the main controller 122 may include a microcontroller unit (MCU) and a memory. The memory stores program code for instructing the MCU to execute a discharge control method. The discharge control method may be summarized as Process 2, as shown in Figure 2. Process 2 includes the following steps:

[0014] Start at step S200.

[0015] In step S202, the motor controller 202 obtains the battery capacity and operation mode of the main battery module 12 to determine the required current of the motor 204.

[0016] In step S204, the main controller 122 obtains the required current, and obtains first information of the main battery 124 and second information of the auxiliary battery 144.

[0017] In step S206, the main controller 122 determines the discharge modes of the main battery 124 and the auxiliary battery 144 according to the first information, the second information and the demand current.

[0018] The process ends in step S208.

[0019] According to Process 2, in step S202, when a user rides the electric assist bicycle 1, the main controller 122 is coupled to the motor controller 202 to obtain a current demand current. The demand current represents the amount of current the motor 204 is expected to draw from the main battery 124 and / or the auxiliary battery 144. Note that the motor controller 202 may obtain the battery capacity of the multi-battery control system 10 via the first communication interface and determine the demand current to draw according to the user's operation mode and the battery capacity of the multi-battery control system 10. In other words, the electric assist bicycle 1 has different demand currents for different driving modes. The operation mode may be, but is not limited to, a sports mode that consumes more power or a power-saving mode that saves relatively less power. In step S204, the main controller 122 obtains first information about the main battery 124 and communicates with the auxiliary controller 142 to obtain second information about the auxiliary battery 144. In detail, the main battery module 12 and the auxiliary battery module 14 may include a battery temperature sensor, a battery voltage sensor, or a battery sensor for detecting a first state of charge (SoC) value, a first battery temperature, and a first battery voltage (first information) of the main battery 124 and a second SoC value, a second battery temperature, and a second battery voltage (second information) of the auxiliary battery 144, respectively. It should be noted that a person skilled in the art may appropriately add other types of sensors and sensing information as needed, but the present invention is not limited to these. In step S206, the main controller 122 determines the discharge modes of the main battery 124 and the auxiliary battery 144 according to the first information, the second information, and the required current, and manages the power of the main battery 124 and the auxiliary battery 144.

[0020] In particular, the main controller 122 may determine whether the first SoC value of the main battery 124 is greater than a first specific value and whether the second SoC value of the auxiliary battery 144 is greater than a second specific value, and may accordingly determine the discharge modes of the main battery 124 and the auxiliary battery 144. In one embodiment, as shown in FIG. 3 , when the first SoC value of the main battery 124 is greater than the first specific value (e.g., 80%), the main controller 122 controls the main battery 124 to supply current (0 A to 20 A) to the motor module 20, and commands the auxiliary controller 142 to control the auxiliary battery 144 to enter a standby mode and not output current to the motor module 20. 4 , when the first SoC value of the main battery 124 is equal to or less than a first specific value (80%) and the second SoC value of the auxiliary battery 144 is greater than a second specific value (3%), the main controller 122 controls the main battery 124 to supply a current (0 A to 20 A) to the motor module 20 and commands the auxiliary controller 142 to control the auxiliary battery 144 to supply a current (5 A) to the motor module 20. Note that when the second SoC value of the auxiliary battery 144 is equal to or less than the second specific value (3%), the main controller 122 commands the auxiliary controller 142 to control the auxiliary battery 144 to enter standby mode. In other words, when the battery capacity of the auxiliary battery 144 is extremely low, the auxiliary battery 144 does not supply a current to the motor module 20, and the remaining battery capacity is used only to maintain communication between the main controller 122 and the auxiliary controller 142. In another embodiment, in addition to determining the discharge mode of the main battery 124 and the auxiliary battery 144 according to the SoC values ​​of the main battery 124 and the auxiliary battery 144 as shown in FIG. 4, the present invention may also add the battery temperatures of the main battery 124 and the auxiliary battery 144 as a determination condition.For example, if the first SoC value of the main battery 124 is less than or equal to a first specific value (80%), the second SoC value of the auxiliary battery 144 is greater than a second specific value (3%), the first battery temperature of the main battery 124 is less than or equal to a first temperature (44°C), and the second battery temperature of the auxiliary battery 144 is less than or equal to a second temperature (69°C), the main controller 122 controls the main battery 124 to supply a current (0 A to 20 A) to the motor module 20, and commands the auxiliary controller 142 to control the auxiliary battery 144 to supply a current (5 A) to the motor module 20. It should be noted that in all embodiments of the present invention, those skilled in the art may appropriately add other types of sensors and sensing information as decision conditions depending on requirements, for example, but not limited to, the temperature of the transistors in the auxiliary battery module 14.

[0021] In one embodiment, when the electrically assisted bicycle 1 is stationary or traveling downhill, the current demand of the motor 204 is in a light load state. In other words, the motor 204 does not need to provide power assistance or only needs to provide a small amount of power assistance. As shown in FIG. 5 , when the current demand of the motor module 20 or the motor 204 is equal to or less than the threshold and the first SoC value of the main battery 124 is equal to or less than a first specific value (5 A), the main controller 122 controls the main battery 124 to not output current and commands the auxiliary controller 142 to control the auxiliary battery 144 to supply current (5 A) to the motor module 20 (2 A) and the main battery 124 (3 A). Note that in the above embodiment, the current supplied from the auxiliary battery 144 may be a fixed value (5 A) and the threshold may be set as a fixed value (5 A). Therefore, when the current demand of the motor module 20 is less than the current (5 A) supplied from the auxiliary battery 144, the motor module 20 draws only a current (2 A) from the auxiliary battery 144. Furthermore, the main controller 122 controls the main battery 124 to transition to a charging mode. Thus, in addition to supplying a current of 2 A to the motor module 20, the auxiliary battery 144 also supplies a current of 3 A to charge the main battery 124.

[0022] On the other hand, when the multi-battery control system 10 is coupled to the charging module 30 and enters the charging mode, the programming code also instructs the MCU to execute a charging control method, which may be summarized as Process 6, as shown in Figure 6. Process 6 includes the following steps:

[0023] Start at step S600.

[0024] In step S602, first information on the main battery 124 and second information on the auxiliary battery 144 are obtained.

[0025] In step S604, the charging modes of the main battery 124 and the auxiliary battery 144 are determined according to the first information and the second information.

[0026] The process ends in step S606.

[0027] According to Process 6, in step S602, the main controller 122 obtains first information of the main battery 124 and communicates with the auxiliary controller 142 to obtain second information of the auxiliary battery 144. As described above, the first information may include a first SoC value, a first battery temperature, and a first battery voltage of the main battery 124. The second information may include a second SoC value, a second battery temperature, and a second battery voltage of the auxiliary battery 144. It should be noted that a person skilled in the art may appropriately add other types of sensors and sensing information as needed, but this is not limited to these. In step S604, the main controller 122 determines charging modes for the main battery 124 and the auxiliary battery 144 according to the first information and the second information, and manages the power of the main battery 124 and the auxiliary battery 144.

[0028] In particular, the main controller 122 may determine whether the power of the main battery 124 is sufficient and accordingly determine the charging modes of the main battery 124 and the auxiliary battery 144. For example, but not limited to, the main controller 122 may determine whether the first battery voltage of the main battery 124 is greater than a first voltage or whether the first SoC value is greater than a first specific value to determine whether the power of the main battery 124 is sufficient. In one embodiment, the charging module 30 may supply a current of 4 A to charge the multi-battery control system 10, and when the first voltage of the main battery 124 is greater than the first voltage (37 V), the main controller 122 controls the main battery 124 and the auxiliary battery 144 to be charged simultaneously. As shown in FIG. 7 , the main controller 122 controls the main battery 124 to receive a current (2 A) supplied from the charging module 30 and commands the auxiliary controller 142 to control the auxiliary battery 144 to receive a current (2 A) supplied from the charging module 30. In other words, if the power of the main battery 124 is sufficient, the main battery 124 and the auxiliary battery 144 may be charged simultaneously. Note that the charging current distribution of the main battery 124 and the auxiliary battery 144 is (2A+2A), but is not limited to this. In another embodiment, as shown in FIG. 7 , in addition to determining the charging mode of the main battery 124 and the auxiliary battery 144 according to the first voltage of the main battery 124, the present invention may also add the battery temperature of the auxiliary battery 144 as a determination condition. For example, if the first voltage of the main battery 124 is greater than the first voltage (37V) and the second battery temperature of the auxiliary battery 144 is equal to or lower than the third temperature (54°C), the main controller 122 controls the main battery 124 and the auxiliary battery 144 to be charged simultaneously. If the first voltage of the main battery 124 is greater than the first voltage (37V) and the second battery temperature of the auxiliary battery 144 is greater than the third temperature (54°C), the main controller 122 controls the main battery 124 to charge and commands the auxiliary battery 144 not to charge or to enter standby mode.8, when the first voltage of the main battery 124 is equal to or lower than the first voltage (37V), the main controller 122 controls the main battery 124 to charge, and commands the auxiliary controller 142 to control the auxiliary battery 144 not to charge or to enter standby mode. In other words, when the power of the main battery 124 is insufficient, all of the charging current (4A) of the charging module 30 is supplied to the main battery 124 for charging.

[0029] In short, the auxiliary controller 142 of the auxiliary battery module 14 of the present invention receives commands from the main controller 122 and determines whether to charge or discharge the auxiliary battery 144. It should be noted that the auxiliary controller 142 is connected only to the main controller 122 via the controller area network CAN, and is not directly connected to the motor controller 202. Therefore, from the perspective of the motor controller 202, the main battery 124 and the auxiliary battery 144 of the multi-battery control system 10 may be regarded as equivalent batteries. For example, if the capacity of the main battery 124 is three times the capacity of the auxiliary battery 144, the capacity and the SoC value of the equivalent battery satisfy the following formula: Equivalent battery capacity = 4 (auxiliary battery capacity) Equivalent battery SoC value = 1 (second SoC value) / 4 + 3 (first SoC value) / 4

[0030] In summary, in the multi-battery control system of the present invention, the main controller controls the main battery and commands the auxiliary controller to control the auxiliary battery to switch between various discharging and charging modes. Therefore, the present invention has the advantages of managing the SoC values ​​of the main battery and the auxiliary battery, thereby improving the utilization efficiency of the main battery and the auxiliary battery and extending the battery life.

[0031] Those skilled in the art will readily appreciate that numerous modifications and variations of the apparatus and method may be made while retaining the teachings of the present invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.

Claims

1. A multi-battery control system for an electric vehicle, comprising: a main battery module including a main controller and a main battery, wherein the main controller controls the main battery to supply current to a motor module of the electric vehicle, and the main controller obtains a first state of charge (SoC) value and a first battery temperature of the main battery; an auxiliary battery module including an auxiliary controller and an auxiliary battery, wherein the main controller controls the auxiliary battery module by communicating with the auxiliary controller using a communication interface, the auxiliary battery module selectively supplies current to the motor module or charges the main battery, and the main controller obtains a second SoC value and a second battery temperature of the auxiliary battery via the communication interface; A multi-battery control system comprising:

2. 2. The multi-battery control system of claim 1, wherein when the first SoC value of the main battery is greater than a first specific value, the main battery supplies current to the motor module, and the main controller controls the auxiliary battery so as not to output current to the motor module.

3. 3. The multi-battery control system of claim 2, wherein when the first SoC value of the main battery is equal to or less than the first specific value and the second SoC value of the auxiliary battery is greater than a second specific value, the main battery and the auxiliary battery simultaneously supply current to the motor module.

4. 4. The multi-battery control system according to claim 3, wherein when the first battery temperature is equal to or lower than a first temperature and the second battery temperature is equal to or lower than a second temperature, the main battery and the auxiliary battery simultaneously supply current to the motor module.

5. 3. The multi-battery control system according to claim 2, wherein the auxiliary battery supplies current to the motor module and the main battery when the required current of the motor module is equal to or less than a threshold value and the first SoC value is equal to or less than the first specific value.

6. The multi-battery control system according to claim 5 , wherein the output current of the auxiliary battery is a fixed value.

7. 2. The multi-battery control system according to claim 1, wherein when the multi-battery control system is in a charging state and the voltage of the main battery is greater than a first voltage, the main controller controls the main battery and the auxiliary battery to be charged simultaneously.

8. 8. The multi-battery control system according to claim 7, wherein when the second battery temperature of the auxiliary battery is equal to or lower than a third temperature, the main controller controls the main battery and the auxiliary battery to be charged simultaneously.

9. 2. The multi-battery control system according to claim 1, wherein when the multi-battery control system is in a charging state and the voltage of the main battery is equal to or lower than a first voltage, the main controller controls the main battery to be charged and the auxiliary battery not to be charged.

10. An electric vehicle, a motor module including a motor and a motor controller, the motor controller controlling the motor to drive and move the electric vehicle; a main battery module including a main controller and a main battery, wherein the main controller controls the main battery to supply current to the motor by communicating with the motor controller using a first communication interface, and the main controller obtains a first state of charge (SoC) value and a first battery temperature of the main battery; an auxiliary battery module including an auxiliary controller and an auxiliary battery, wherein the main controller controls the auxiliary battery module by communicating with the auxiliary controller using a second communication interface, the auxiliary battery module selectively supplies current to the motor module or charges the main battery, and the main controller obtains a second SoC value and a second battery temperature of the auxiliary battery via the second communication interface; An electric vehicle equipped with

11. 11. The electric vehicle of claim 10, wherein when the first SoC value of the main battery is greater than a first specific value, the main battery supplies current to the motor module, and the main controller controls the auxiliary battery not to output current to the motor module.

12. 12. The electric vehicle of claim 11, wherein when the first SoC value of the main battery is less than or equal to the first specific value and the second SoC value of the auxiliary battery is greater than a second specific value, the main battery and the auxiliary battery simultaneously supply current to the motor module.

13. 13. The electric vehicle of claim 12, wherein the main battery and the auxiliary battery simultaneously supply current to the motor module when the first battery temperature is equal to or lower than a first temperature and the second battery temperature is equal to or lower than a second temperature.

14. 12. The electric vehicle according to claim 11, wherein the auxiliary battery supplies current to the motor module and the main battery when the required current of the motor module is equal to or less than a threshold value and the first SoC value is equal to or less than the first specific value.

15. 15. The electric vehicle according to claim 14, wherein the output current of the auxiliary battery is a fixed value.

16. 11. The electric vehicle according to claim 10, wherein when the multi-battery control system including the main battery module and the auxiliary battery module is in a charging state and the voltage of the main battery is greater than a first voltage, the main controller controls the main battery and the auxiliary battery to be charged simultaneously.

17. 17. The electric vehicle of claim 16, wherein when the second battery temperature of the auxiliary battery is equal to or lower than a third temperature, the main controller controls the main battery and the auxiliary battery to be charged simultaneously.

18. 11. The electric vehicle according to claim 10, wherein when the multi-battery control system including the main battery module and the auxiliary battery module is in a charging state and the voltage of the main battery is equal to or lower than a first voltage, the main controller controls the main battery to be charged and the auxiliary battery not to be charged.

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