Lithium battery on-load recovery circuit

Abstract

The utility model relates to the field of battery protection and management, and discloses a lithium battery on-load recovery circuit, which comprises a time-delay turn-off unit used for controlling the disconnection of a load in a time-delay manner after the protection action of a lithium battery pack; the time-delay starting unit is used for controlling the load to be accessed again in a time-delay manner after the output of the lithium battery pack is recovered; the load cut-off unit is used for realizing disconnection and connection of the load according to the control signals of the delay turn-off unit and the delay turn-on unit; wherein the time-delay turn-off unit and the time-delay turn-on unit are respectively composed of an analog time-delay circuit composed of a resistor, a capacitor and a triode, the whole circuit is realized without a digital logic chip, and the time-delay time can be set by adjusting the parameters of the resistor and the capacitor so as to adapt to different load characteristics. According to the utility model, a pure analog circuit delay control technology is adopted, the standby power consumption is only microampere level, the service life of a battery is greatly prolonged, and the strict requirement of a mining intrinsic safety system on low power consumption is met.

Description

Technical Field

[0001] This utility model relates to the technical field of battery protection and management, specifically to a lithium battery load recovery circuit. Background Technology

[0002] Existing intrinsically safe lithium battery packs for mining are widely used in communication, lighting, and monitoring systems in underground coal mines. To ensure safety, lithium battery protection circuits with fast protection features are typically used. When a momentary inrush current occurs during load startup, the protection circuit will quickly trip and cut off the output. To restore the output, it is often necessary to disconnect the load and reconnect the power, which is cumbersome and affects system stability.

[0003] Currently, some load recovery solutions on the market typically rely on digital logic circuits, such as microcontrollers and application-specific integrated circuits (ASICs), for control. However, these designs suffer from problems such as high power consumption, high complexity, and insufficient anti-interference capabilities, making it difficult to meet the requirements of intrinsically safe mining equipment for extremely low power consumption, extremely high reliability, and a simple and stable structure.

[0004] Therefore, there is an urgent need for a circuit solution that requires no digital logic circuits, has extremely low power consumption, high reliability, and can achieve load recovery. Utility Model Content

[0005] The purpose of this invention is to provide a lithium battery load recovery circuit that addresses the problems of high power consumption, complex structure, insufficient anti-interference capability, and inability to meet the requirements of low-power applications in existing lithium battery protection and recovery processes.

[0006] To achieve the above-mentioned objectives, this utility model adopts the following technical solution: a lithium battery load recovery circuit, comprising:

[0007] The delayed shutdown unit is used to delay the disconnection of the load after the lithium battery pack protection action is activated;

[0008] The delayed start unit is used to delay the reconnection of the load after the lithium battery pack resumes output;

[0009] The load disconnection unit is used to disconnect and connect the load according to the control signals of the delay shutdown unit and the delay start unit;

[0010] The delay-off unit and the delay-on unit are both composed of analog delay circuits consisting of resistors, capacitors and transistors. The entire circuit does not require digital logic chips, and the delay time can be set by adjusting the resistor and capacitor parameters to adapt to different load characteristics.

[0011] Preferably, the delayed shutdown unit includes resistors R1 and R2 connected in series, which are connected across the two ends of the switching transistor in the battery protection circuit. The midpoint of the series connection is connected to the base of transistor N1. Resistor R2 is connected in parallel with capacitor C1. The emitter of transistor N1 is connected to the negative terminal B- of the battery pack. The collector outputs a delayed shutdown control signal.

[0012] Preferably, the delay-on unit includes resistors R3 and R4 connected in series, which are connected across the positive and negative terminals of the battery pack. The midpoint of the series connection is connected to the base of transistor N2. Resistor R4 is connected in parallel with capacitor C2. The emitter of transistor N2 is connected to the negative terminal B- of the battery pack. The collector outputs a delay-on control signal.

[0013] Preferably, the load cut-off unit includes resistors R5 and R6 connected in series, with the center point of the series connection connected to the gate of the field-effect transistor Q1. Resistor R5 is connected to the output terminal of the delay-on unit, and resistor R6 is connected to the positive terminal B+ of the battery pack. The source of the field-effect transistor Q1 is connected to the positive terminal B+ of the battery pack, and the drain is connected to the positive terminal P+ of the load output terminal.

[0014] Preferably, the static power consumption of both the delay-off unit and the delay-on unit is in the microampere range, so as to ensure that the overall circuit has extremely low power consumption characteristics.

[0015] Preferably, the load disconnection unit controls the connection and disconnection of the load current path by turning the field-effect transistor Q1 on and off, thereby avoiding malfunctions caused by load impacts during the protection recovery process.

[0016] Preferably, the delay time is set by adjusting the parameters of resistors R1, R2, R3, R4 and capacitors C1, C2 to flexibly set the turn-off and turn-on delay times to adapt to different load characteristics.

[0017] Compared with existing technologies, a lithium battery load recovery circuit using the above-mentioned technical solution has the following advantages:

[0018] First, it adopts pure analog circuit delay control technology, with standby power consumption at the microampere level, which greatly extends battery life and meets the strict requirements of intrinsically safe mining systems for low power consumption; it avoids the use of microcontrollers or complex digital circuits, with a simple circuit structure, strong anti-interference ability, and can still maintain stable operation under harsh conditions; it automatically controls the load to recover after the protection action is cleared, without manual intervention, which improves the system's automation level and ease of use.

[0019] Second, it uses simple conventional components such as resistors, capacitors, transistors and field-effect transistors, resulting in low design and manufacturing costs, easy mass production and maintenance. It is not only suitable for intrinsically safe lithium battery packs in coal mines, but also for other portable energy systems or safe power supply equipment that require low power consumption and high reliability. Attached Figure Description

[0020] Figure 1 The schematic diagram of the lithium battery load recovery circuit is shown in the embodiment.

[0021] In the diagram: B+ represents the positive terminal of the battery pack; B- represents the negative terminal of the battery pack; P+ represents the positive terminal of the load output; P- represents the negative terminal of the load output; R1, R2, R3, R4, R5, and R6 are resistors; C1 and C2 are capacitors; N1 and N2 are transistors; and Q1 is a field-effect transistor. Detailed Implementation

[0022] The preferred embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0023] See Figure 1 As shown, the present invention provides a lithium battery load recovery circuit, comprising: a time-delayed shutdown unit, a time-delayed start unit, and a load cut-off unit, wherein the units are electrically connected to form an overall control system.

[0024] The delayed shutdown unit includes resistors R1 and R2 connected in series, with the series connection center point connected to the base of transistor N1. Resistor R2 and capacitor C1 are connected in parallel to form a delayed charge / discharge circuit. The emitter of transistor N1 is connected to the negative terminal B- of the battery pack, and the collector outputs a delayed shutdown control signal.

[0025] The delayed-on unit includes resistors R3 and R4 connected in series, with the center point of the series connection connected to the base of transistor N2. Resistor R4 and capacitor C2 are connected in parallel, forming a delayed charge / discharge circuit. The emitter of transistor N2 is connected to the negative terminal B- of the battery pack, and the collector outputs a delayed-on control signal.

[0026] The load cut-off unit includes resistors R5 and R6 connected in series, with the center point of the series connection connected to the gate of the field-effect transistor Q1. Resistor R5 is connected to the output terminal of the delay-on unit, and resistor R6 is connected to the positive terminal B+ of the battery pack. The source of the field-effect transistor Q1 is connected to B+, and the drain is connected to the positive terminal P+ of the load output.

[0027] During operation, when the lithium battery pack triggers protection due to abnormal conditions such as overcurrent or short circuit, the delayed shutdown unit starts the delay timer. After a preset time, it outputs a low-level control signal to turn off the field-effect transistor Q1, thereby cutting off the load and preventing the protection circuit from being continuously affected by the load, ensuring that the protection state is maintained stably.

[0028] When the external fault is resolved and the lithium battery pack resumes normal output, the delay start unit begins to delay. After the set delay, it outputs a low-level control signal to turn Q1 back on, the load is restored, and the system power supply is normal without user intervention.

[0029] In practical applications, the delay off time and delay on time can be flexibly adjusted according to different application requirements. The specific method is to adjust the delay length by changing the resistance values ​​of resistors R1, R2, R3, and R4 (generally in the range of 10kΩ to 1MΩ) and the capacitance values ​​of capacitors C1 and C2 (generally in the range of 1μF to 100μF).

[0030] This invention controls the overall static power consumption to below 10μA, making it suitable for intrinsically safe lithium battery systems used in energy-sensitive mining applications. Furthermore, since it is implemented entirely with discrete components, it eliminates the need for microcontroller control, thus avoiding system failures caused by malfunctions in the logic control chip.

[0031] More preferably, the field-effect transistor Q1 can be a low on-resistance, high voltage withstand model (such as IRLML6402) to reduce the on-state voltage drop and improve system efficiency.

[0032] With the above settings, this utility model not only achieves precise load control during the protection and recovery phase, but also adapts to different load impact characteristics and different recovery timing requirements, making it widely applicable to application scenarios with strict requirements for low power consumption and high reliability, such as portable devices, mining equipment, and emergency lighting equipment.

[0033] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A lithium battery load recovery circuit, characterized in that, include: The delayed shutdown unit is used to delay the disconnection of the load after the lithium battery pack protection action is activated; The delayed start unit is used to delay the reconnection of the load after the lithium battery pack resumes output. The load disconnection unit is used to disconnect and connect the load according to the control signals of the delay shutdown unit and the delay start unit; The delay shutdown unit and the delay turn-on unit are both composed of analog delay circuits consisting of resistors, capacitors and transistors. The entire circuit does not require digital logic chips, and the delay time can be set by adjusting the resistor and capacitor parameters to adapt to different load characteristics.

2. A lithium battery on-board recovery circuit according to claim 1, characterized in that: The delayed shutdown unit includes resistors R1 and R2 connected in series, which are connected across the two ends of the switching transistor in the battery protection circuit. The midpoint of the series connection is connected to the base of transistor N1. Resistor R2 and capacitor C1 are connected in parallel. The emitter of transistor N1 is connected to the negative terminal B- of the battery pack. The collector outputs a delayed shutdown control signal.

3. The lithium battery on-board recovery circuit of claim 1, wherein: The delayed-on unit includes resistors R3 and R4 connected in series, which are connected across the positive and negative terminals of the battery pack. The midpoint of the series connection is connected to the base of transistor N2. Resistor R4 is connected in parallel with capacitor C2. The emitter of transistor N2 is connected to the negative terminal B- of the battery pack. The collector outputs a delayed-on control signal.

4. A lithium battery on-board recovery circuit according to any one of claims 1 to 3, characterized in that, The load cut-off unit includes resistors R5 and R6 connected in series, with the center point of the series connection connected to the gate of the field-effect transistor Q1. Resistor R5 is connected to the output terminal of the delay-on unit, and resistor R6 is connected to the positive terminal B+ of the battery pack. The source of the field-effect transistor Q1 is connected to the positive terminal B+ of the battery pack, and the drain is connected to the positive terminal P+ of the load output.

5. The lithium battery on-board recovery circuit of claim 1, wherein, The static power consumption of both the delay-off unit and the delay-on unit is in the microampere range, ensuring that the overall circuit has extremely low power consumption characteristics.

6. A lithium battery on-board recovery circuit according to claim 4, wherein, The load disconnection unit controls the connection and disconnection of the load current path by turning the field-effect transistor Q1 on and off, thereby avoiding malfunctions caused by load impacts during the protection recovery process.

7. The lithium battery on-board recovery circuit of claim 3, wherein: The delay time is set by adjusting the parameters of resistors R1, R2, R3, R4 and capacitors C1, C2 to flexibly set the turn-off and turn-on delay times to adapt to different load characteristics.

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