Lithium battery charging and discharging management device

Abstract

The utility model relates to the technical field of lithium battery management, and particularly discloses a lithium battery charging and discharging management device, which comprises a lithium battery pack, a charging and discharging circuit, a master control MCU (Microprogrammed Control Unit), a voltage acquisition circuit, a current acquisition circuit, a protection circuit and a power supply module, the main control MCU is in signal connection with the voltage acquisition circuit and the current acquisition circuit, the power supply module and the charging and discharging circuit respectively supply power to the main control MCU, the voltage acquisition circuit and the current acquisition circuit, and the protection circuit is connected with the main control MCU and is used for providing over-charging, over-discharging and over-current protection for a lithium battery pack.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery management technology, and in particular to a lithium battery charge and discharge management device. Background Technology

[0002] With the widespread application of electronic devices and electric vehicles, lithium batteries have become the preferred energy source due to their high energy density, long cycle life, and low self-discharge rate. However, lithium battery charge and discharge management is a complex process; improper charging or discharging can lead to performance degradation, shortened lifespan, and even safety issues. While existing lithium battery charge and discharge management systems have addressed these problems to some extent, they still have shortcomings. For example, existing management systems often cannot accurately monitor the operating status of each individual lithium battery cell, making it difficult to achieve balanced management in multi-cell applications. Furthermore, some systems lack effective protection mechanisms and cannot promptly and effectively address issues such as overcharging, over-discharging, and overcurrent, which not only affects battery lifespan but may also pose safety hazards. Therefore, developing a lithium battery charge and discharge management device that can accurately monitor battery status and provide comprehensive protection is particularly important. Summary of the Invention

[0003] In view of the above-mentioned prior art, the present invention provides a lithium battery charging and discharging management device, which mainly solves the technical problems existing in the background art.

[0004] To achieve the above objectives, the technical solution of this utility model embodiment is implemented as follows: A lithium battery charging and discharging management device includes a lithium battery pack and a charging and discharging circuit electrically connected to the lithium battery pack. The lithium battery pack contains multiple individual lithium batteries and further includes: a main control MCU, a voltage acquisition circuit, a current acquisition circuit, a protection circuit, and a power module. The main control MCU is signal-connected to the voltage acquisition circuit and the current acquisition circuit. The power module and the charging and discharging circuit supply power to the main control MCU, the voltage acquisition circuit, and the current acquisition circuit, respectively. The protection circuit is connected to the main control MCU and is used to provide overcharge, over-discharge, and overcurrent protection for the lithium battery pack.

[0005] Optionally, the main control MCU is an XC164 series microcontroller.

[0006] Optionally, the voltage acquisition circuit includes a first subtraction operational amplifier circuit composed of an XL4301 operational amplifier chip. The XL4301 operational amplifier chip is connected to the main control MCU signal. The same input terminal (A) and the inverting input terminal (B) of the XL4301 operational amplifier chip are respectively connected to the positive and negative terminals of the single lithium battery. The detected voltage analog signal of the single lithium battery is amplified by the first subtraction operational amplifier circuit composed of the XL4301 operational amplifier chip and then transmitted to the main control MCU.

[0007] Optionally, the current acquisition circuit includes a resistor Rz and a second subtraction operational amplifier circuit composed of an LM324DR operational amplifier chip, wherein the resistor Rz is connected in series to the charging and discharging circuit, the LM324DR operational amplifier chip is connected to both ends of the resistor Rz, and the LM324DR operational amplifier chip is connected to the main control MCU signal.

[0008] Optionally, the protection circuit includes an overcurrent protection circuit, an overcharge protection circuit, and an over-discharge protection circuit. Each of the overcurrent protection circuit, overcharge protection circuit, and over-discharge protection circuit includes a MOS field-effect transistor, and all three circuits are connected to the charging and discharging circuit.

[0009] Optionally, the power module includes an LM2575D2T-12 power chip and an LM2575D2T-5 power chip. The LM2575D2T-5 power chip supplies power to the main control MCU, and the LM2575D2T-12 power chip supplies power to the LM324DR op-amp chip and the XL4301 op-amp chip.

[0010] The beneficial effects of this invention are as follows: By integrating a main control MCU, voltage acquisition circuit, current acquisition circuit, protection circuit, and power module, comprehensive management and protection of the lithium battery pack are achieved. First, the main control MCU adopts a high-performance XC164 series microcontroller, possessing an efficient instruction set and multiple addressing modes, enabling fast and accurate processing of acquired data and ensuring the system's real-time performance and stability. Second, the voltage and current acquisition circuits, respectively using subtraction amplifier circuits composed of XL4301 and LM324DR operational amplifier chips, achieve high-precision acquisition of the voltage and current of individual lithium batteries, ensuring data accuracy. Furthermore, the protection circuit, including overcurrent protection, overcharge protection, and over-discharge protection circuits, utilizes the fast response of MOSFETs to immediately cut off the charging and discharging circuits upon detecting abnormal conditions, effectively preventing overcharging, over-discharging, and overcurrent, significantly improving the safety and reliability of the lithium battery pack. Finally, the LM2575D2T series power chip in the power module provides a stable power supply, ensuring the normal operation of the entire system. In summary, this invention not only improves the management accuracy and safety of lithium battery packs, but also extends the battery's lifespan, thus possessing significant practical application value. Attached Figure Description

[0011] Figure 1 This is a block diagram of the lithium battery charge and discharge management device in the embodiments of this application;

[0012] Figure 2 This is a pin diagram of the XC164 microcontroller in the embodiments of this application;

[0013] Figure 3 This is a circuit diagram of the voltage acquisition circuit in an embodiment of this application;

[0014] Figure 4 This is a circuit diagram of the power module in an embodiment of this application;

[0015] Explanation of icon numbers:

[0016] 1. Main control MCU; 2. Voltage acquisition circuit; 3. Current acquisition circuit; 4. Protection circuit. Detailed Implementation

[0017] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. 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 utility model belongs. The terminology used in this specification of this utility model is for the purpose of describing particular embodiments only and is not intended to limit the utility model. In the following description, the expression "some embodiments" refers to a subset of all possible embodiments; however, it should be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments and can be combined with each other without conflict.

[0018] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid confusion with the present invention.

[0019] It should be understood that this invention can be embodied in various forms and should not be construed as limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this invention to those skilled in the art. Furthermore, the terminology used herein is intended only to describe particular embodiments and is not intended to limit the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “compose” and / or “comprising,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0020] It should also be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "inner," "outer," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0021] To fully understand this utility model, a detailed structure will be presented in the following description to illustrate the technical solution proposed by this utility model. Optional embodiments of this utility model are described in detail below; however, in addition to these detailed descriptions, this utility model may have other embodiments.

[0022] Example

[0023] Please refer to the attached document. Figures 1 to 4 This application provides a lithium battery charging and discharging management device, including a lithium battery pack and a charging and discharging circuit electrically connected to the lithium battery pack. The lithium battery pack contains multiple individual lithium batteries and further includes: a main control MCU1, a voltage acquisition circuit 6, a current acquisition circuit 3, a protection circuit 4, and a power module. The main control MCU1 is signal-connected to the voltage acquisition circuit 6 and the current acquisition circuit 3. The power module and the charging and discharging circuit supply power to the main control MCU1, the voltage acquisition circuit 6, and the current acquisition circuit 3, respectively. The protection circuit 4 is connected to the main control MCU1 and is used to provide overcharge, over-discharge, and overcurrent protection for the lithium battery pack.

[0024] Specifically, the lithium battery charging and discharging management device provided in this application is used to collect the individual voltage of a single lithium battery through a voltage acquisition circuit 6 and to collect the current of the lithium battery pack through a current acquisition circuit 3. The acquisition results of the individual voltage of the single lithium battery and the acquisition results of the current of the lithium battery pack are transmitted to the main control MCU1. The main control MCU1 outputs a corresponding PWM adjustment signal to drive the protection circuit 4 to switch the charging and discharging circuit on and off, thereby realizing overcharge, over-discharge and overcurrent protection of the lithium battery pack.

[0025] In an optional implementation, the main control MCU1 adopts an XC164 series microcontroller, whose main functions include: data acquisition: the microcontroller uses the built-in ADC module to acquire the battery voltage and current data in real time and convert the analog signal into a digital signal;

[0026] Data processing: The acquired digital signals are processed and calculated by the microcontroller program to analyze the battery status, such as voltage, current, temperature and other parameters, and to determine whether there are abnormal conditions such as overcharging, over-discharging, and overcurrent.

[0027] Control Output: Based on the processed data and preset control logic, the XC164 series microcontroller controls the overcurrent and overcharge protection modules by outputting I / O signals to prevent the battery from overcharging, overcurrent and other problems.

[0028] Furthermore, the XC164 microcontroller is a high-performance, low-power 16-bit microcontroller widely used in automotive electronics, industrial control, consumer electronics, and communications. Based on the C166SV2 core, the XC164 series microcontrollers have abundant peripheral resources and powerful processing capabilities. They include PWM modules, I / O modules, interrupt modules, analog-to-digital conversion modules, and other functional modules, enabling the system to perform functions such as battery voltage monitoring, current monitoring, balance control, and analog-to-digital conversion of voltage values. The XC164 can operate at a frequency of up to 40MHz and provide a processing capability of up to 40MIPS (millions of instructions per second).

[0029] The C166SV2 kernel supports an efficient instruction set and multiple addressing modes, featuring a highly efficient pipelined architecture that enables fast instruction execution and efficient task processing. Furthermore, the XC164 kernel supports hardware multiplication and division instructions, further enhancing computational performance.

[0030] The XC164 integrates a variety of peripheral interfaces to meet the needs of various applications, including:

[0031] Serial Communication Interface: The XC164 is equipped with multiple serial communication interfaces, including three high-speed asynchronous / synchronous serial interfaces (USART), supporting full-duplex communication and various communication protocols such as UART, LIN, and SPI. Timer and Capture / Compare Units:

[0032] The XC164 has up to five built-in 16-bit timers, supports multiple counting modes and capture / compare functions, and can achieve precise time control and event capture.

[0033] Analog-to-Digital Converter (ADC): The XC164 is equipped with a 10-bit ADC module with 16 analog input channels, enabling fast and high-precision analog signal acquisition. Watchdog Timer: A built-in watchdog timer automatically resets the system in case of a fault, enhancing system reliability.

[0034] The XC164 employs multiple low-power design strategies to effectively reduce power consumption while maintaining performance. Its low-power modes include idle mode and sleep mode, in which the XC164 can shut down some functional modules to reduce system power consumption. Furthermore, the XC164 supports dynamic frequency scaling and power management, automatically adjusting the operating frequency and voltage based on system load to further optimize power performance.

[0035] In an optional embodiment, the voltage acquisition circuit 6 includes a first subtraction operational amplifier circuit composed of an XL4301 operational amplifier chip. The XL4301 operational amplifier chip is connected to the main control MCU1. The same input terminal (A) and the inverting input terminal (B) of the XL4301 operational amplifier chip are respectively connected to the positive and negative terminals of a single lithium battery cell. The detected analog voltage signal of the single lithium battery cell is amplified by the first subtraction operational amplifier circuit composed of the XL4301 operational amplifier chip and then transmitted to the main control MCU1.

[0036] The XL4301 op-amp chip is a general-purpose, low-power integrated quad op-amp, comprising four independent high-gain and frequency-compensated op-amps. It can be used with a single supply (3–30V) or dual supply (+1.5–±15V), features low power consumption, and is compatible with TTL logic circuits. Its features include sprint-protected output, true differential input stage, input electrostatic discharge protection, and internal compensation.

[0037] When acquiring and monitoring the terminal voltage of a single battery, the same input terminal (A) and the inverting input terminal (B) of the XL4301 operational amplifier chip are connected to the positive and negative terminals of the lithium battery, respectively. The detected battery voltage analog signal is amplified by a subtraction circuit composed of the XL4301 operational amplifier chip, differentially calculated, and then transmitted to the analog-to-digital converter built into the XC164 microcontroller for processing. After A / D conversion by the XC164 microcontroller, the terminal voltage value of each individual lithium battery is successfully obtained.

[0038] In an optional embodiment, the current acquisition circuit 3 includes a resistor Rz and a second subtraction operational amplifier circuit composed of an LM324DR operational amplifier chip, wherein the resistor Rz is connected in series to the charging and discharging circuit, the LM324DR operational amplifier chip is connected to both ends of the resistor Rz, and the LM324DR operational amplifier chip is connected to the main control MCU1 signal.

[0039] Specifically, a 0.0052Ω resistor is connected in series in the charging and discharging circuit of the lithium battery pack. Using a small resistor allows for accurate current detection without generating excessive power consumption. Because the voltage across the series resistor is too small, a subtraction operational amplifier circuit composed of an LM324DR operational amplifier chip is used to detect the voltage across the series resistor in the lithium battery pack to improve accuracy. Based on the resistance and voltage values, the current flowing through the resistor is obtained, thus revealing the current output of the lithium battery pack.

[0040] In an optional embodiment, the protection circuit 4 includes an overcurrent protection circuit, an overcharge protection circuit, and an over-discharge protection circuit. Each of the overcurrent protection circuit, overcharge protection circuit, and over-discharge protection circuit includes a MOS field-effect transistor, and all three circuits are connected to the charging and discharging circuit.

[0041] Specifically, during the discharge process of the lithium battery pack, when the voltage acquisition circuit 6 detects that the voltage of a single cell is lower than 2.7V, the PIC microcontroller directly controls the MOS field-effect transistor in the over-discharge protection circuit to cut off the discharge branch in the charging and discharging circuit to avoid over-discharge.

[0042] Similarly, when the voltage or current threshold is exceeded, the MOSFETs in the overcurrent protection circuit and overcharge protection circuit will operate to disconnect the circuit.

[0043] Similarly, this application selects the RU75110R type MOSFET as the system control switch transistor. It contains an internal parasitic diode, which effectively prevents the MOSFET from being damaged and protects it. By consulting its datasheet, its drain-source rated voltage V... DS Up to 75V, gate voltage Vcs is +25V, drain current ID can reach 110A, on-resistance R DS(ON) It is 5.5m 2 Calculated using formulas 42 and 43, its switching loss is approximately 0.19W, which basically meets the power requirements of the system.

[0044] In one optional implementation, the power module includes an LM2575D2T-12 power chip and an LM2575D2T-5 power chip. The LM2575D2T-5 power chip supplies power to the main control MCU1, and the LM2575D2T-12 power chip supplies power to the LM324DR op-amp chip and the XL4301 op-amp chip.

[0045] Both the LM2575D2T-12 and LM2575D2T-5 power chips belong to the LM2575D2T integrated voltage regulator chip family. They integrate a fixed oscillator, requiring only a few external components to form a high-efficiency voltage regulator circuit, significantly reducing the size of the heatsink. The LM2575D2T offers a wide operating input voltage range, with a maximum input voltage of 37V, high efficiency, stable output voltage, and low power consumption. These characteristics fully meet the requirements of battery management systems for power step-down modules. The LM2575D2T-12 power chip supplies power to a 12V integrated operational amplifier, while the LM2575D2T-5 power chip supplies power to a 5V microcontroller.

[0046] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. The protection scope of this utility model should be determined by the protection scope of the stated claims.

Claims

1. A lithium battery charge / discharge management device, comprising a lithium battery pack and a charge / discharge circuit electrically connected to the lithium battery pack, wherein the lithium battery pack contains a plurality of individual lithium batteries, characterized in that, Also includes: The system includes a main control MCU, a voltage acquisition circuit, a current acquisition circuit, a protection circuit, and a power supply module. The main control MCU is connected to the voltage acquisition circuit and the current acquisition circuit. The power supply module and the charging / discharging circuit supply power to the main control MCU, the voltage acquisition circuit, and the current acquisition circuit, respectively. The protection circuit is connected to the main control MCU and is used to provide overcharge, over-discharge, and overcurrent protection for the lithium battery pack.

2. The lithium battery charge and discharge management device according to claim 1, characterized in that, The main control MCU adopts the XC164 series microcontroller.

3. The lithium battery charge and discharge management device according to claim 1, characterized in that, The voltage acquisition circuit includes a first subtraction operational amplifier circuit composed of XL4301 operational amplifier chips. The XL4301 operational amplifier chips are connected to the main control MCU. The same input terminal (A) and the inverting input terminal (B) of the XL4301 operational amplifier chips are connected to the positive and negative terminals of a single lithium battery cell, respectively. The detected analog voltage signal of the single lithium battery cell is amplified by the first subtraction operational amplifier circuit composed of XL4301 operational amplifier chips and then transmitted to the main control MCU.

4. The lithium battery charge and discharge management device according to claim 3, characterized in that, The current acquisition circuit includes a resistor Rz and a second subtraction operational amplifier circuit composed of an LM324DR operational amplifier chip. The resistor Rz is connected in series to the charging and discharging circuit, and the LM324DR operational amplifier chip is connected to both ends of the resistor Rz. The LM324DR operational amplifier chip is connected to the main control MCU signal.

5. A lithium battery charge and discharge management device according to claim 4, characterized in that, The protection circuit includes an overcurrent protection circuit, an overcharge protection circuit, and an over-discharge protection circuit. Each of the overcurrent protection circuit, overcharge protection circuit, and over-discharge protection circuit contains a MOS field-effect transistor, and all three circuits are connected to the charging and discharging circuit.

6. The lithium battery charge and discharge management device according to claim 5, characterized in that, The power module includes an LM2575D2T-12 power chip and an LM2575D2T-5 power chip. The LM2575D2T-5 power chip supplies power to the main control MCU, and the LM2575D2T-12 power chip supplies power to the LM324DR op-amp chip and the XL4301 op-amp chip.

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