A short-circuit self-protection and isolation system for lithium batteries

Abstract

This utility model relates to the field of lithium battery technology and discloses a lithium battery short-circuit self-protection and isolation system, including a detection module, a control module, a first self-protection module, a second self-protection unit, and an isolation module; the first self-protection module receives control commands from the control module and cuts off the main circuit; the second self-protection unit receives signals from the detection module and directly drives a first MOS transistor to cut off the circuit; the isolation module receives control commands from the control module and isolates the faulty battery; the output terminal of the detection module is connected to the input terminals of the control module and the second self-protection module, the output terminal of the control module is connected to the input terminal of the first self-protection module, and the output terminal of the control module is connected to the input terminal of the isolation module.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, specifically to a short-circuit self-protection and isolation system for lithium batteries. Background Technology

[0002] With the widespread application of lithium batteries in consumer electronics, electric vehicles, and energy storage systems, their safety has become increasingly critical. Short circuits in lithium batteries pose a significant risk of thermal runaway, fires, and even explosions. Traditional short-circuit protection systems have the following shortcomings:

[0003] (1) Existing technology only shuts off the main circuit, but cannot achieve electrical isolation between the faulty battery and the main circuit. If a short circuit or thermal runaway occurs, the fault current may spread to the entire battery pack through parasitic capacitance, common-mode interference or grounding loop, causing cascading damage.

[0004] (2) It relies on a single protection scheme, which has a probability of failure and lacks redundancy design.

[0005] Therefore, this application proposes a short-circuit self-protection and isolation system for lithium batteries, which effectively solves the above-mentioned shortcomings. Utility Model Content

[0006] (a) Technical problems to be solved

[0007] To address the shortcomings of existing technologies, this application provides a short-circuit self-protection and isolation system for lithium batteries.

[0008] (II) Technical Solution

[0009] To address the above problems, this application provides the following technical solution:

[0010] A short-circuit self-protection and isolation system for lithium batteries includes:

[0011] The detection module is used to monitor the charging and discharging current and voltage of the battery pack in real time and identify short circuit conditions;

[0012] The control module receives signals from the detection module, analyzes and judges them, and triggers the first self-protection module;

[0013] The first self-protection module receives the control command from the control module and disconnects the main circuit;

[0014] The second self-protection unit receives the signal from the detection module and directly drives the first MOS transistor to cut off the circuit.

[0015] The isolation module receives control commands from the control module and isolates the faulty battery.

[0016] The output terminal of the detection module is connected to the input terminal of the control module and the second self-protection module, the output terminal of the control module is connected to the input terminal of the first self-protection module, and the output terminal of the control module is connected to the input terminal of the isolation module.

[0017] Preferably, the detection module includes a current detection unit and a voltage detection unit; the current detection unit includes a sampling resistor, an amplifier, and a comparator; the voltage detection unit includes a filter capacitor and a voltage divider resistor.

[0018] Preferably, the control module includes a microcontroller.

[0019] Preferably, the control module further includes a wireless communication unit, through which the control module performs bidirectional data transmission with a remote server; the remote server receives the data information from the control module, provides a mobile terminal interface to display the status of the lithium battery, and remotely issues control commands.

[0020] Preferably, the first self-protection module includes a first transistor, a resistor, a 12V power supply, and a first MOSFET.

[0021] Preferably, the second self-protection module includes a second transistor, a resistor, a 12V power supply, and a first MOSFET.

[0022] Preferably, the isolation module includes an isolator, a driver, a second MOSFET, and a third MOSFET.

[0023] (III) Beneficial Effects

[0024] Compared with the prior art, this application provides a lithium battery short-circuit self-protection and isolation system, which has the following beneficial effects:

[0025] 1. The system can detect short-circuit current and voltage anomalies in real time and uses a dual trigger protection mechanism to cut off the main circuit and avoid thermal runaway, fire and explosion caused by short circuit;

[0026] 2. The system also achieves electrical isolation by disconnecting the faulty battery from the main circuit through the isolation module; when a single battery experiences a short circuit or thermal runaway, the isolation module can quickly disconnect the faulty battery from the main circuit to prevent the fault current from spreading to the entire battery pack or other equipment.

[0027] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0028] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0029] Figure 1 This is a schematic diagram of a short-circuit self-protection and isolation system for a lithium battery according to this application;

[0030] Figure 2 This is a circuit diagram of a lithium battery short-circuit self-protection and isolation system according to this application.

[0031] Reference numerals: 1 Detection module, 2 Control module, 3 First self-protection module, 4 Second self-protection module, 5 Isolation module. Detailed Implementation

[0032] 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.

[0033] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0034] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0035] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0036] Please see Figures 1-2 This application provides a new technical solution: a lithium battery short-circuit self-protection and isolation system, comprising: a detection module 1, a control module 2, a first self-protection module 3, a second self-protection module 4, and an isolation module 5;

[0037] Detection module 1 includes a current detection unit 110 and a voltage detection unit 120;

[0038] The current detection unit 110 includes a sampling resistor R1, an amplifier U2, and a comparator U3.1. The sampling resistor R1 is connected in series between the lithium battery H1 and the load H2. The amplifier U2 is connected in parallel across the resistor R1. The output of the amplifier U2 is filtered by RC and then connected to the non-inverting input of the comparator U3.1. The inverting input is connected to the reference voltage R4 and R3 divided from the positive terminal of the lithium battery H1.

[0039] The voltage detection unit 120 includes a filter capacitor C4, voltage divider resistors R3 and R4.

[0040] The control module 3 includes a microcontroller U1, which can be an STM32 series microcontroller.

[0041] Pin PA0 of microcontroller U1 is connected to voltage detection unit 120, pin PA1 of microcontroller U1 is connected to current detection unit 110, and pins PA9 and PA10 of microcontroller U1 are connected to wireless communication unit 320.

[0042] The first self-protection module 3 includes a first transistor Q4, a 12V power supply, a resistor R10, and a first MOSFET Q1. The first transistor Q4 is connected to pin PB0 of the microcontroller U1. A resistor R6 is connected in series between the first transistor Q4 and the microcontroller U1. The collector of the first transistor Q4 is connected to the first MOSFET Q1. The microcontroller U1 receives control commands from the remote server 6, outputs a high-level signal, turns on the first transistor Q4, and drives the first MOSFET Q1 to cut off the circuit.

[0043] The second self-protection module 4 includes a second transistor Q3, a capacitor C3, a 12V power supply, resistors R6 and R7, and a first MOSFET Q1. The base of the second transistor Q3 is connected to the comparator U3.1, and the resistor R6 is connected in series between the second transistor Q3 and the comparator U3.1. The base of the second transistor Q3 is connected to the 12V power supply. The emitter of the second transistor Q3 is grounded. The collector of the second transistor Q3 is connected to the resistor R7 and the capacitor C3. When a short circuit occurs, C3 discharges quickly through R7, accelerating the turn-off of the first MOSFET Q1. The collector of the second transistor Q3 is connected to the gate of the first MOSFET Q1, the source of the first MOSFET Q1 is connected to the load H2, and the drain of the first MOSFET Q1 is connected to the sampling resistor R1.

[0044] In this embodiment, when a short circuit occurs, the voltage at the non-inverting input terminal of comparator U3.1 is greater than the inverting input voltage, comparator U3.1 outputs a high level, turns on the second transistor Q3, and drives the first MOSFET Q1 to cut off the circuit.

[0045] In this embodiment, the microcontroller U1 receives signals from the voltage detection unit 120 and the current detection unit 110, and transmits the signals to the remote server 6; the microcontroller U1 also receives control commands from the remote server 6 to drive the first MOS transistor Q1 to cut off the circuit.

[0046] The second self-protection module 4 has a higher priority than the first self-protection module 3.

[0047] In the embodiment, the second self-protection module 4 and the first self-protection module 3 can use the same MOSFET or two MOSFETs to form two branches. When two MOSFETs are used, the second self-protection module 4 and the first self-protection module 3 are connected to the main circuit through an OR gate. When one MOSFET triggers a signal, the main circuit is cut off.

[0048] The isolation module 5 includes an isolator U9, a driver U7, a second MOSFET Q2, and a third MOSFET Q5. Pin VIA of isolator U9 is connected to pin PB1 of microcontroller U1, pin GND1 of isolator U9 is connected to pin GND of microcontroller U1, pin VDD2 of isolator U9 is connected to the isolation power supply, and pin VDD1 of isolator U9 is connected to pin VCC of microcontroller U1. Pin VOA of isolator U9 is connected to pin IN of driver U7, pin GND2 of isolator U9 is connected to ground via GND of driver U7, and two pins OUT of isolator U9 are connected to the gates of the second MOSFET Q2 and the third MOSFET Q5, respectively. The second MOSFET Q2 and the third MOSFET Q5 are connected in series to the positive and negative terminals of lithium battery H1.

[0049] The workflow of isolation module 5 is as follows:

[0050] If the microcontroller U1 does not detect a short circuit, the drive signal turns on the second MOSFET Q2 and the third MOSFET Q5, connecting the lithium battery to the main circuit. When a short circuit occurs: the detection module 1 detects the short circuit and triggers the microcontroller U1. After analyzing the signal, the microcontroller U1 outputs an isolation control command. The isolation module 2 transmits the control signal to the driver U7 through the isolator U9. The driver U7 quickly turns off the second MOSFET Q2 and the third MOSFET Q5, cutting off the main circuit. After fault isolation, the isolation module 2 keeps the second MOSFET Q2 and the third MOSFET Q5 in the off state until manual reset or system restart.

[0051] In the description of this specification, references to "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0052] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A lithium battery short circuit self-protection and isolation system, characterized in that, include: The detection module is used to monitor the charging and discharging current and voltage of the battery pack in real time and identify short circuit conditions; The control module receives signals from the detection module, analyzes and judges them, and triggers the first self-protection module; The first self-protection module receives the control command from the control module and disconnects the main circuit; The second self-protection unit receives the signal from the detection module and directly drives the first MOS transistor to cut off the circuit. The isolation module receives control commands from the control module and isolates the faulty battery. The output terminal of the detection module is connected to the input terminal of the control module and the second self-protection module, the output terminal of the control module is connected to the input terminal of the first self-protection module, and the output terminal of the control module is connected to the input terminal of the isolation module.

2. A short circuit self-protection and isolation system for lithium batteries according to claim 1, characterized in that, The detection module includes a current detection unit and a voltage detection unit; the current detection unit includes a sampling resistor, an amplifier, and a comparator; the voltage detection unit includes a filter capacitor and a voltage divider resistor.

3. The lithium battery short-circuit self-protection and isolation system according to claim 1, characterized in that, The control module includes a microcontroller.

4. The lithium battery short-circuit self-protection and isolation system according to claim 1, characterized in that, The control module also includes a wireless communication unit, through which the control module performs bidirectional data transmission with a remote server; the remote server receives the data information from the control module, provides a mobile terminal interface to display the status of the lithium battery, and remotely issues control commands.

5. A lithium battery short-circuit self-protection and isolation system according to claim 1, characterized in that, The first self-protection module includes a first transistor, a resistor, a 12V power supply, and a first MOSFET.

6. A lithium battery short-circuit self-protection and isolation system according to claim 1, characterized in that, The second self-protection module includes a second transistor, a resistor, a 12V power supply, and a first MOSFET.

7. A lithium battery short-circuit self-protection and isolation system according to claim 1, characterized in that, The isolation module includes an isolator, a driver, a second MOSFET, and a third MOSFET.

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