A battery management system with charging current limiting function

Abstract

A battery management system with charging current limiting function includes a microcontroller unit, a voltage and current detection module, a temperature detection module, and a current limiting execution module. The voltage and current detection module, temperature detection module, and current limiting execution module are respectively connected to different pins of the microcontroller unit. The voltage and current detection module includes a chip U24. The VS pin of chip U24 is connected to a 100nF filter capacitor C121. The Alert pin of chip U24 is connected to a resistor R170, and the SDA pin of chip U24 is connected to a resistor R167. Through precise current sampling and a real-time overcurrent protection mechanism, it can effectively prevent overheating, fire, and other safety accidents caused by overcurrent charging, ensuring the safe operation of the battery under various complex charging conditions.

Description

Technical Field

[0001] This utility model relates to the field of battery management, specifically a battery management system with charging current limiting function. Background Technology

[0002] With the continuous expansion of battery applications, such as home energy storage, energy storage power stations, and portable electronic devices, the requirements for battery performance and safety are increasing. As a key component ensuring the safe and efficient operation of batteries, the battery management system (BMS) plays a crucial role in current limiting. Traditional BMS current limiting methods have several shortcomings. On the one hand, when faced with differences in the output characteristics of different charging devices and dynamic changes in battery state, it is difficult to accurately and flexibly adjust the charging current, which can easily lead to overcharging and overheating, shortening battery life and even causing safety hazards. For example, when using an incompatible charger to charge a home energy storage battery, excessive charging current may cause an imbalance in the battery's internal chemical reactions, accelerating battery capacity degradation. On the other hand, existing current limiting circuit designs are complex and costly, and their control precision and response speed cannot meet the needs of modern battery management, limiting the application and promotion of BMS in a wider range of scenarios. Utility Model Content

[0003] The purpose of this invention is to provide a battery management system with charging current limiting function to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: In one aspect, this application provides a battery management system with charging current limiting function, including a microcontroller unit, a voltage and current detection module, a temperature detection module, and a current limiting execution module. The voltage and current detection module, temperature detection module, and current limiting execution module are respectively connected to different pins of the microcontroller unit. The voltage and current detection module includes a chip U24, whose VS pin is connected to a 100nF filter capacitor C121. The Alert pin of the chip U24 is connected to a resistor R170, and the SDA pin of the chip U24 is connected to a resistor R167. The SCL pin of chip U24 is connected to resistor R168, and resistors R167, R168, and R170 have the same resistance value. The current limiting execution module includes amplifier U32, whose non-inverting input pin is connected to filter capacitor C155, and whose inverting input pin is connected to resistors R153 and R154, which are connected in series and are current-adjusting resistors. The temperature detection module includes four-channel temperature detection circuits, each of which includes two resistors and one capacitor connected in series.

[0005] In one possible implementation, the amplifier's GND pin is connected to ground, and its VCC pin is connected to a switching buck chip.

[0006] In one possible implementation, the non-inverting input pin of the amplifier is also connected to a resistor R155, and the inverting input pin of the amplifier is connected to a reference module.

[0007] In one possible implementation, the reference module includes capacitors C150, C151, and C152, a Zener diode, resistors R140 and R139. The capacitors C150, C151, C152, and Zener diode are connected in parallel. One end of resistor R140 is connected to the inverting input pin of the amplifier, and the other end is connected to capacitor C152. One end of resistor R139 is connected to the switching buck chip, and the other end is connected to capacitor C150.

[0008] In one possible implementation, the output pin of the amplifier is connected to the switching power supply pulse width modulation control chip, and a capacitor C156, a resistor R156, a capacitor C157, and a resistor R157 are sequentially provided between the output pin of the amplifier and the switching power supply pulse width modulation control chip.

[0009] In one possible implementation, the VIN+ pin of the chip U24 is connected to resistor R171, the VIN- pin is connected to resistor R172, and a capacitor C124 is provided between resistor R171 and resistor R172.

[0010] Based on the same inventive concept, in a second aspect, embodiments of this application provide a battery system, including the battery management system as described in the first aspect.

[0011] Based on the same inventive concept, in a third aspect, embodiments of this application provide an electrical device including a battery system as described in any embodiment of the first aspect.

[0012] Compared with the prior art, the present invention has the following advantages: Through precise current sampling and real-time overcurrent protection mechanisms, it can effectively prevent safety accidents such as overheating and fire caused by overcurrent charging, and ensure the safe operation of the battery under various complex charging conditions. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a circuit diagram of the voltage and current detection module of this utility model; Figure 3 This is a circuit diagram of the current limiting execution module of this utility model; Figure 4 This is a circuit diagram of the temperature detection module of this utility model. Detailed Implementation

[0014] To further illustrate the technical means and effects adopted by this utility model in order to achieve the intended utility model purpose, the following detailed description of the specific implementation methods, structure, features and effects of this utility model is provided in conjunction with the accompanying drawings and preferred embodiments.

[0015] like Figure 1 As shown, a battery management system with charging current limiting function includes a microcontroller unit 10, a voltage and current detection module 20, a temperature detection module 40, and a current limiting execution module 30. The voltage and current detection module 20, the temperature detection module 40, and the current limiting execution module 30 are respectively connected to different pins of the microcontroller unit.

[0016] The microcontroller unit 10 uses an MCU microcontroller. The MCU microcontroller analyzes the voltage and current values ​​of the lithium battery during operation collected by the voltage and current detection module and the temperature value collected by the temperature detection module. It then applies a current limiting execution module to limit the current to 10A, thereby improving battery safety and extending battery life.

[0017] The specific structure of each module is explained below, such as... Figure 2 As shown, the voltage and current detection module 20 includes a chip U24. The VS pin of chip U24 is connected to a filter capacitor C121, which is 100nF and can effectively reduce the delay time. The Alert pin of chip U24 is connected to a resistor R170, the SDA pin is connected to a resistor R167, and the SCL pin is connected to a resistor R168. The resistance values ​​of resistors R167, R168, and R170 are the same. The VIN+ pin is connected to a resistor R171, and the VIN- pin is connected to a resistor R172. A capacitor C124 and a resistor R173 are located between resistors R171 and R172. Capacitor C124 and resistor R173 are connected in parallel. Chip U24 can be an INA226AIDGSR model chip, and the input voltage of the voltage and current detection module is 3V. The resistance value connected to the VIN+ and VIN- pins can be measured using the Spread Resistance Profile (SRP) method, thereby monitoring the current. SRP technology is based on the spread resistance model formed by the contact between a metal probe and a semiconductor. When the probe contacts the sample surface with constant pressure, the current diffuses radially at the contact point, and the resulting spread resistance value is inversely proportional to the local carrier concentration.

[0018] like Figure 3As shown, the current limiting execution module 30 includes an amplifier U32. The non-inverting input pin of the amplifier is connected to a filter capacitor C155, and the inverting input pin is connected to resistors R153 and R154, which are connected in series and serve as current-regulating resistors. The amplifier's GND pin is connected to ground, and its VCC pin is connected to a switching buck chip XL. The non-inverting input pin of the amplifier is also connected to resistor R155. The amplifier's output pin is connected to a switching power supply pulse width modulation control chip TL494. Between the amplifier's output pin and the switching power supply pulse width modulation control chip TL494, capacitor C156, resistor R156, capacitor C157, and resistor R157 are sequentially arranged. The amplifier's inverting input pin is connected to a reference module.

[0019] The reference voltage of the reference module is 2.5V, and the amplifier's operating voltage is 12V. The circuit of the reference module is described below. The reference module includes capacitors C150, C151, and C152, a Zener diode, resistors R140 and R139. Capacitors C150, C151, and C152, along with the Zener diode, are connected in parallel. One end of resistor R140 is connected to the amplifier's inverting input pin, and the other end is connected to capacitor C152. One end of resistor R139 is connected to the switching buck converter chip XL, and the other end is connected to capacitor C150. The amplification effect of the amplifier is then measured using the reference module as a reference.

[0020] like Figure 4 As shown, the temperature detection module 40 includes four temperature detection circuits, each comprising two resistors and one capacitor connected in series. The resistors are NTC thermistors. For example, the first temperature detection circuit T1A includes capacitor C38, resistors R62 and R63; the second temperature detection circuit T2A includes capacitor C37, resistors R60 and R61; the third temperature detection circuit T3A includes capacitor C36, resistors R58 and R59; and the fourth temperature detection circuit T4A includes capacitor C35, resistors R56 and R57.

[0021] The four temperature detection circuits are connected in parallel, and the voltage of the temperature detection circuits is the same as that of the reference module, which is 2.5V.

[0022] Based on the same inventive concept, this application also provides a battery system, including the aforementioned battery management system with charging current limiting function. It is understood that the battery system has the beneficial effects of the battery management system with charging current limiting function provided in this application embodiment. For details, please refer to the specific descriptions of the battery management system with charging current limiting function in the above embodiments; these descriptions will not be repeated here.

[0023] Based on the same inventive concept, this application also provides an electrical device. The electrical device includes the aforementioned battery system. It is understood that the electrical device has the beneficial effects of the battery management system provided in the embodiments of this application. For details, please refer to the specific descriptions of the battery management system with charging current limiting function in the above embodiments, which will not be repeated here.

[0024] In the description of this utility model, it should be understood that the terms "coaxial", "bottom", "one end", "top", "middle", "other end", "upper", "side", "top", "inner", "front", "center", "both ends", "left and right", "front and back", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0025] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," "fixing," "screw connection," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0026] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any indirect modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A battery management system with charging current limiting function, characterized in that, The system includes a microcontroller unit, a voltage and current detection module, a temperature detection module, and a current limiting execution module. These modules are connected to different pins of the microcontroller unit. The voltage and current detection module includes a chip U24. The VS pin of chip U24 is connected to a 100nF filter capacitor C121. The Alert pin of chip U24 is connected to a resistor R170, and the SDA pin is connected to a resistor R167. The SCL pin of chip U24... The pin is connected to resistor R168, and resistors R167, R168, and R170 have the same resistance value; the current limiting execution module includes amplifier U32, the non-inverting input pin of the amplifier is connected to filter capacitor C155, and the inverting input pin of the amplifier is connected to resistors R153 and R154, which are connected in series and are current regulating resistors; the temperature detection module includes four temperature detection circuits, each of which includes two resistors and one capacitor connected in series.

2. The battery management system with charge current limiting function according to claim 1, characterized in that, The amplifier's GND pin is connected to ground, and its VCC pin is connected to the switching buck chip.

3. The battery management system with charge current limiting function according to claim 2, characterized in that, The non-inverting input pin of the amplifier is also connected to a resistor R155, and the inverting input pin of the amplifier is connected to a reference module.

4. The battery management system with charge current limiting function according to claim 3, characterized in that, The reference module includes capacitors C150, C151, and C152, a Zener diode, resistors R140 and R139. Capacitors C150, C151, and C152 and the Zener diode are connected in parallel. One end of resistor R140 is connected to the inverting input pin of the amplifier, and the other end is connected to capacitor C152. One end of resistor R139 is connected to the switching buck chip, and the other end is connected to capacitor C150.

5. The battery management system with charge current limiting function according to claim 4, characterized in that, The output pin of the amplifier is connected to the pulse width modulation control chip of the switching power supply. Between the output pin of the amplifier and the pulse width modulation control chip of the switching power supply, there are capacitors C156, R156, C157 and R157 arranged in sequence.

6. The battery management system with charge current limiting function according to claim 1, wherein, The VIN+ pin of the chip U24 is connected to resistor R171, and the VIN- pin is connected to resistor R172. A capacitor C124 is provided between resistor R171 and resistor R172.

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