A battery management module

Abstract

The utility model discloses a battery management module is located in two wheel electric vehicle, with the charger adaptation, including, singlechip circuit and with respectively connecting singlechip circuit, power supply circuit is for singlechip circuit and the power supply of peripheral circuit on electric motor car, current sampling circuit gathers working current for obtaining battery input and output current, communication circuit is used for the identification and matching after charger connection. Solveed the current charging management module communication interference problem and the problem of function module separation.

Description

Technical Field

[0001] This application relates to an electric vehicle management circuit, and more particularly to a battery management module. Background Technology

[0002] In recent years, with the mandatory implementation of the new national standard for electric bicycles, charging safety and battery management accuracy have become core technical requirements. The new standard requires that battery packs and chargers achieve "mutual recognition and collaborative charging" through communication protocols to avoid the risk of incompatible charging, while also requiring real-time collection of parameters such as battery voltage, temperature, and current. However, most ordinary household electric two-wheelers use lead-acid batteries, and the strong electromagnetic interference (EMI) generated by the switching power supply during charging will superimpose complex noise waveforms on the communication lines, seriously hindering communication stability.

[0003] In battery management, users are increasingly demanding higher accuracy in displaying remaining battery charge (SOC). Current technologies often exhibit significant errors in electric vehicle battery level displays; for example, they may display a longer driving time even when the battery is actually low on charge.

[0004] The current solution has two major flaws:

[0005] Communication interference issue: Lead-acid batteries use a "two-plus-two" interface (two power lines + two communication lines), which is physically susceptible to interference from power lines. Although some solutions have attempted to eliminate the independent communication lines, they have not solved the signal distortion problem in strong interference scenarios.

[0006] Functional module separation: Charging interoperability and power calculation functions are usually implemented by independent modules. For example, the battery monitoring circuit is responsible for data acquisition, and the central control module (such as a microcontroller) handles communication. This discrete design increases hardware costs and system complexity, which conflicts with users' need for "cost optimization".

[0007] Therefore, an integrated solution is urgently needed: while ensuring the anti-interference capability of the new national standard communication protocol, to achieve accurate SOC calculation through high-precision current classification sampling, and to integrate the dual functions into a single battery management module to optimize costs. Utility Model Content

[0008] This utility model discloses a battery management module that solves the problems of communication interference and functional module separation in current charging management modules.

[0009] A battery management module, installed in a two-wheeled electric vehicle and adapted to a charger, includes a microcontroller circuit and components respectively connected to the microcontroller circuit.

[0010] The power supply circuit provides power to the microcontroller circuit and the peripheral circuits of the electric vehicle.

[0011] The current sampling circuit collects the operating current to obtain the battery input and output current.

[0012] Communication circuitry, used for identification and matching after the charger is connected.

[0013] In this application, the current sampling circuit and the communication circuit are integrated into the battery management module to solve the problem of separate design of charging mutual recognition function and power calculation function, which increases hardware cost and system complexity.

[0014] Several alternative methods are provided below, but they are not intended as additional limitations on the overall solution above. They are merely further additions or optimizations. Provided there are no technical or logical contradictions, each alternative method can be combined individually with respect to the overall solution above, or multiple alternative methods can be combined with each other.

[0015] Optionally, the current sampling circuit includes a first current sampling circuit acting on the power supply circuit, used to perform integral calculations on the current of the microcontroller and peripheral circuits.

[0016] Optionally, the current sampling circuit further includes a second current sampling circuit acting on the charging and discharging circuit where the battery is located, used to perform integral calculation on the current in the charging and discharging circuit.

[0017] Optionally, the current sampling circuit further includes a third current acquisition circuit acting on the motor drive circuit, used to perform integral calculation on the current consumed by the drive motor.

[0018] Optionally, the communication circuit is provided with a signal input terminal and a signal output terminal, and an anti-interference circuit is provided on the signal output terminal.

[0019] Optionally, the anti-interference circuit uses an optocoupler, and the power supply circuit connects the light-emitting diode on the optocoupler to the positive terminal of the phototransistor. The positive terminal potential of the phototransistor serves as the output signal of the signal output terminal.

[0020] The beneficial effects of this application are as follows:

[0021] 1. The current sampling circuit provided in this application includes a first current sampling circuit for integrating small currents, a second current sampling circuit for calculating the charging and discharging of the battery, and a third current acquisition circuit for integrating the current consumed by the drive motor. High-precision current classification sampling of different current magnitudes enables accurate calculation of remaining battery power.

[0022] 2. The communication circuit in this application is equipped with an anti-interference circuit with an optocoupler as its core, which can isolate interference noise. Attached Figure Description

[0023] Figure 1 This is a power supply circuit in one embodiment of this application;

[0024] Figure 2 This is a microcontroller circuit in one embodiment of this application;

[0025] Figure 3 This is a current sampling circuit in one embodiment of this application;

[0026] Figure 4 This is a reference voltage circuit for an operational amplifier in one embodiment of this application;

[0027] Figure 5 This is a communication circuit in one embodiment of this application. Detailed Implementation

[0028] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] It should be noted that when a component is said to be "connected" to another component, it can be directly connected to the other component or it can be connected to a component in between. When a component is said to be "set on" another component, it can be directly set on the other component or it may be set to a component in between.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0031] refer to Figures 1 to 5 This application discloses a battery management module, which is set at the vehicle end of an electric bicycle and adapted to the charger end. It collects the input current on the battery when charging and collects the output current on the battery when the electric bicycle is working.

[0032] In one embodiment of this application, the battery management module includes a microcontroller circuit, a power supply circuit for supplying power to the microcontroller circuit and the peripheral circuits on the electric vehicle, a current sampling circuit for acquiring the battery input and output current, and a communication circuit for identifying and matching the charger.

[0033] It should be noted that the aforementioned peripheral circuits include low-current electrical components on the electric vehicle, such as: instruments, vehicle lights, etc.

[0034] Because the transient operating current of an electric bicycle can range from a few milliamps to more than 100 amps when it is in operation, and the charging current can reach about 6 amps, high-precision sampling of the current is necessary to accurately calculate the remaining power.

[0035] In one embodiment of this application, the current sampling circuit includes a first current sampling circuit, a second current sampling circuit, and a third current acquisition circuit, which are each independently configured.

[0036] The system comprises three current sampling circuits: a first current sampling circuit for acquiring current consumption in the microcontroller circuit and peripheral circuits; a second current sampling circuit for sampling the charging current in the battery charging / discharging circuit and acquiring the charging current from the charger to the battery; and a third current acquisition circuit for acquiring current consumption in the motor drive circuit when the motor is operating. Sampling the corresponding ranges for these three operating currents ensures sampling accuracy in different scenarios, enabling accurate calculation of remaining battery power.

[0037] refer to Figure 3 In one embodiment, the first current sampling circuit includes a resistor R10 and an operational amplifier circuit disposed across the resistor R10, including an operational amplifier U4A, the output of which is connected to a microcontroller circuit.

[0038] Furthermore, one end of resistor R10 is connected to the common negative terminal of the microcontroller circuit and peripheral circuits (or the ground where current converges on the microcontroller circuit and peripheral circuits). (Therefore, in one embodiment, one end of resistor R10 can be connected as follows...) Figure 3 One end is directly connected to the negative terminal of the instrument, and the other end is connected to the reference ground.

[0039] In one embodiment, the second current sampling circuit includes a resistor R11, one end of which is connected to the charger output ground (i.e., the charger negative), and the other end is connected to a reference ground. The two ends of the resistor R11 are connected to a microcontroller circuit, and the signal is amplified by the microcontroller's built-in operational amplifier and transmitted to the microcontroller's AD function channel for frequent and accurate sampling and calculation of the charging current.

[0040] In one embodiment, the third current acquisition circuit includes a resistor R9, one end of which is connected to battery ground (i.e., battery negative), and the other end is connected to a reference ground. The two ends of resistor R9 are connected to an operational amplifier circuit including operational amplifier U4B. The output of operational amplifier U4B is connected to a microcontroller circuit to sample and calculate the current consumed by the drive motor.

[0041] In one embodiment, the charger and the electric vehicle have communication and identification functions for battery and charger identification and matching. This communication function is achieved through communication circuits integrated into the battery management module and located within the charger.

[0042] It should be noted that the communication circuit in the battery management module of this application is a part of the circuit that realizes the above-mentioned communication and identification functions (it can be divided into the electric vehicle end and the charger end according to the setting position, and the same communication circuit is set in both ends (see reference)). Figure 5 (The two communication circuits are connected by a K-line.) Communication and identification functions can be realized after the connection is completed between the electric vehicle end and the charger end.

[0043] As described above, after the communication circuit is connected between the electric vehicle and the charger, it is used for mutual recognition between the charger and the battery. After mutual recognition is completed, it communicates to provide feedback on the battery voltage to the charger at different battery charge levels, so as to change the charging mode.

[0044] The communication circuit (referring to the part integrated in the battery management module for communicating with the charger) has a signal input terminal and a signal output terminal. The signal input terminal is used to receive signals from the charger, and the signal output terminal is used to send signals to the charger.

[0045] Furthermore, an anti-interference circuit is provided on the aforementioned signal output terminal to filter out noise generated during signal transmission.

[0046] Specifically, the anti-interference circuit is an optocoupler. The signal input terminal is connected to a light-emitting diode inside the optocoupler, and the signal output terminal is connected to a phototransistor inside the optocoupler. This anti-interference circuit isolates the current between the signal input and signal output terminals. (Reference) Figure 5 The phototransistor and LED on optocoupler U2 are connected to a 5V power supply, with the phototransistor's voltage level serving as the signal output at terminal RXD0. The LED's conduction on optocoupler U2 is controlled by the charger, as the communication circuits on the charger and electric vehicle sides are identical (see reference). Figure 5 (Lower half) The signal input terminal TXD0 controls the transistor Q2 to conduct, which in turn turns on the LED on the optocoupler. That is, the signal input terminal on the charger controls the LED on the optocoupler U2 on the electric vehicle side to conduct, and the signal output terminal RXD0 outputs the signal.

[0047] In some embodiments, the battery management module of this application further includes a motor drive circuit for driving the motor to work. The motor drive circuit is connected to the microcontroller circuit and is controlled by the microcontroller circuit to drive the motor to work.

[0048] The technical features of the embodiments described above can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered to be within the scope of this specification. When technical features of different embodiments are embodied in the same drawing, it can be regarded as the drawing also disclosing examples of combinations of the various embodiments involved.

[0049] The embodiments described above are merely examples of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application.

Claims

1. A battery management module, installed inside a two-wheeled electric vehicle and adapted to a charger, characterized in that, Includes a microcontroller circuit, and components respectively connected to the microcontroller circuit. The power supply circuit provides power to the microcontroller circuit and the peripheral circuits of the electric vehicle. The current sampling circuit collects the operating current to obtain the battery input and output current. The communication circuit is equipped with an anti-interference circuit for charger connection matching and filtering signal interference.

2. The battery management module according to claim 1, characterized in that, The current sampling circuit includes a first current sampling circuit that acts on the power supply circuit, used to perform integral calculations on the current of the microcontroller and peripheral circuits.

3. A battery management module according to claim 2, characterized in that, The current sampling circuit further includes a second current sampling circuit that acts on the charging and discharging circuit where the battery is located, for integrating and calculating the current on the charging and discharging circuit.

4. A battery management module according to claim 3, characterized in that, The current sampling circuit also includes a third current acquisition circuit that acts on the motor drive circuit to perform integral calculations on the current consumed by the drive motor.

5. A battery management module according to claim 1, characterized in that, The communication circuit is provided with a signal input terminal and a signal output terminal, and the anti-interference circuit is provided on the signal output terminal.

6. A battery management module according to claim 5, characterized in that, The anti-interference circuit uses an optocoupler. The power supply circuit connects the light-emitting diode on the optocoupler to the positive terminal of the phototransistor, and uses the positive terminal potential of the phototransistor as the output signal of the signal output terminal.

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