Device for detecting liquid leakage of battery pack and battery pack

Abstract

The utility model provides a device for detecting liquid leakage of a battery pack and the battery pack, and relates to the technical field of batteries, and the device comprises a liquid leakage sensor module, a water inlet and a water outlet which are arranged on a box body of the battery pack; and the liquid leakage detection circuit is fixed on the inner wall of the box body and is electrically connected with the liquid leakage sensor module and a battery management system of the battery pack. The device has the beneficial effects that liquid leakage is detected through the liquid leakage sensor modules arranged at the water inlet and the water outlet of the box body, the insulation resistance of the total positive and negative of the battery pack to the shell does not need to be detected, and liquid leakage and water inflow of the battery pack are rapidly and accurately detected; the liquid leakage sensor module and the battery management system are connected through the liquid leakage detection module, so that the voltage change condition of the liquid leakage sensor module can be fed back to the battery management system in time when liquid leakage occurs, and the system can be freely matched with multiple battery management manufacturers to improve the applicability.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a device for detecting battery pack leakage and a battery pack. Background Art

[0002] With the booming electric vehicle (EV) industry and rapidly advancing technology, the pursuit of battery technology safety has reached unprecedented heights. Faced with the rapid growth of the global EV market, major automakers are increasing their investment in battery pack system safety, particularly by introducing advanced cooling systems to optimize battery performance and extend battery life. However, once a lithium battery pack experiences leakage, it not only directly threatens the stable operation of the battery system but can also cause catastrophic consequences such as short circuits, fires, and even explosions. Therefore, effective monitoring of battery pack leakage has become a critical component in ensuring the safety of electric vehicles.

[0003] Against this backdrop, the battery pack leakage sensor detection module emerged. Its design philosophy is rooted in a deep understanding of and relentless pursuit of battery safety. Leveraging high-precision sensing technology, the module monitors the fluid status and level changes within the battery pack in real time, acting as a kind of intelligent "protective suit" for the battery pack. Upon detecting any abnormal leakage, the sensor responds immediately, accurately reflecting the leak through changes in resistance, and quickly sends an alert signal to the battery management system (BMS), acting like a sentinel guarding the battery's safety.

[0004] The application of this technology not only significantly enhances battery pack safety monitoring capabilities, achieving a shift from passive response to active prevention, but also provides users with a more secure and worry-free driving experience while ensuring the operational reliability of electric vehicles. By promptly detecting and addressing leakage issues, the battery pack leakage sensor detection module effectively reduces the safety risks caused by battery failure, laying a solid foundation for the sustainable development of the electric vehicle industry.

[0005] However, existing battery system leakage detection uses insulation detection to measure the insulation impedance of the total positive and negative terminals of the battery pack to the shell. This method has a relatively slow detection time and delays the triggering of the alarm, posing a safety risk.

[0006] Existing battery system leakage detection uses a leakage sensor module. This method is relatively limited. The current battery management system (BMS) hardware cannot support directly obtaining the leakage signal of the leakage sensor module. Utility Model Content

[0007] In view of the problems existing in the prior art, the present invention provides a device for detecting battery pack leakage, comprising:

[0008] A liquid leakage sensor module is arranged at the water inlet and outlet of the box body of the battery pack;

[0009] A liquid leakage detection circuit is fixed on the inner wall of the box body and is electrically connected to the liquid leakage sensor module and the battery management system of the battery pack.

[0010] Preferably, the liquid leakage sensor module includes at least two liquid leakage sensor units;

[0011] Each of the liquid leakage sensors is respectively fixed at the water inlet and outlet of the box body through a fixing member;

[0012] The voltage detection pin of the liquid leakage sensor unit is connected to the voltage acquisition pin of the liquid leakage detection circuit, and the ground pin of the liquid leakage sensor unit is connected to the ground pin of the liquid leakage detection circuit.

[0013] Preferably, the liquid leakage sensor unit includes:

[0014] A first resistor, one end of the first resistor serves as a power supply pin and is connected to a power supply, the other end of the first resistor is connected to one end of a second resistor and one end of a first pin, the other end of the second resistor is connected to one end of a first capacitor and the voltage acquisition pin, and the other end of the first capacitor is grounded;

[0015] A second pin, one end of the second pin is connected to the ground pin of the liquid leakage detection circuit;

[0016] A variable resistor, both ends of the variable resistor are respectively connected to the other end of the first pin and the other end of the second pin, and a third resistor is also connected in parallel between the first pin and the second pin.

[0017] Preferably, the liquid leakage detection circuit includes:

[0018] A main chip, the main chip is provided with a plurality of the voltage acquisition pins, each of the voltage acquisition pins is respectively connected to the voltage detection pin of a liquid leakage sensor unit, and further includes a plurality of ground pins, each of the ground pins is respectively connected to the ground pin of a liquid leakage sensor unit;

[0019] A CAN transceiver, the high-level signal pin of the CAN transceiver is connected to the high-level signal pin of the main chip, the low-level signal pin of the CAN transceiver is connected to the low-level signal pin of the main chip, and the CAN transceiver is also connected to the battery management system;

[0020] The power supply pin of the main chip is connected to the battery body in the battery pack.

[0021] Preferably, the fixing member is in a "U" shape.

[0022] Preferably, a mounting hole is provided in the fixing member, and the liquid leakage sensor unit is mounted in the mounting hole.

[0023] Preferably, the variable resistor in the liquid leakage sensor unit faces the bottom of the box, and the first pin and the second pin extend vertically upward.

[0024] The utility model also provides a battery pack, comprising the above-mentioned device for detecting battery pack leakage.

[0025] The above technical solution has the following advantages or beneficial effects:

[0026] 1) Leakage is detected by the leakage sensor module installed at the water inlet and outlet of the box, without the need to detect the insulation impedance of the total positive and negative terminals of the battery pack to the shell, and leakage and water ingress of the battery pack can be detected quickly and accurately;

[0027] 2) The leakage sensor module and the battery management system are connected through a leakage detection circuit, which can promptly feed back the voltage change of the leakage sensor module to the battery management system when leakage occurs. It can be freely combined with multiple battery management manufacturers to improve applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a structural diagram of a device for detecting battery pack leakage installed in a battery pack in a preferred embodiment of the present utility model;

[0029] Figure 2 This is a circuit diagram of a liquid leakage sensor unit in a preferred embodiment of the present invention;

[0030] Figure 3 This is a circuit diagram of a liquid leakage detection circuit in a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0031] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. The present invention is not limited to this embodiment, and other embodiments may also fall within the scope of the present invention as long as they conform to the main purpose of the present invention.

[0032] In a preferred embodiment of the present invention, based on the above-mentioned problems existing in the prior art, a device for detecting battery pack leakage is provided, comprising:

[0033] The leakage sensor module 1 is provided at the water inlet and outlet of the battery pack box 2;

[0034] The leakage detection circuit 3 is fixed to the inner wall of the box 2 and is electrically connected to the leakage sensor module 3 and the battery management system of the battery pack.

[0035] Specifically, in this embodiment, a liquid leakage sensor module 1 is provided near the water outlet and water inlet on the bottom plate of the box body 2 of the battery pack to detect liquid leakage in real time. When liquid leakage occurs, the voltage of the liquid leakage sensor module 1 changes. The liquid leakage detection circuit 3 sends the voltage change situation to the battery management system in real time to achieve liquid leakage detection, solving the problems of the traditional method of detecting the insulation impedance between the total positive and total negative of the battery pack and the shell through insulation detection, which has a relatively lagging detection, delayed alarm triggering, and potential safety hazard risks, and realizing fast and accurate detection; and solving the problem that the hardware of the battery management system (BMS) cannot directly support obtaining the liquid leakage signal of the liquid leakage sensor module 1, and it can be freely combined with multiple battery management manufacturers to improve applicability.

[0036] In a preferred embodiment of the present invention, the liquid leakage sensor module 1 includes at least two liquid leakage sensor units 11;

[0037] Each liquid leakage sensor unit 11 is respectively fixed at the water inlet and water outlet of the box body 2 through a fixing member 12;

[0038] The fixing member 12 is in a "U" shape; the fixing member 12 is provided with mounting holes, and the liquid leakage sensor unit 11 is installed in the mounting holes;

[0039] The voltage detection pin of the liquid leakage sensor unit 11 is connected to the voltage acquisition pin of the liquid leakage detection circuit 3, and the ground pin of the liquid leakage sensor unit 11 is connected to the ground pin of the liquid leakage detection circuit 3.

[0040] Specifically, as Figure 1 shown, two liquid leakage sensor units 11 are shown, which are respectively installed near the water inlet and water outlet of the box body 2 because liquid leakage often occurs at these two positions. Of course, in actual use, the number of liquid leakage sensor units 11 can be increased and installed at other positions on the bottom plate of the box body 2 to increase the detection range and improve the accuracy and timeliness of liquid leakage detection.

[0041] Through Figure 1 it can be seen that the liquid leakage sensor unit 11 is installed on the bottom plate of the box body through a "U" - shaped fixing member 12. The "U" - shaped fixing member 12 not only has better stability, but also has a certain redundant space below the fixing member 12, which can adjust the distance between the liquid leakage sensor unit 11 and the bottom plate.

[0042] In a preferred embodiment of the present invention, the liquid leakage sensor unit 11 includes:

[0043] A first resistor R1, one end of the first resistor R1 is connected to the power supply VCC as a power supply pin, the other end of the first resistor R1 is connected to one end of the second resistor R2 and one end of the first pin PIN1, the other end of the second resistor R2 is connected to one end of the first capacitor C1 and the voltage collection pin, and the other end of the first capacitor C1 is grounded;

[0044] A second pin PIN2, one end of the second pin PIN2 is connected to the ground pin GND of the leakage detection circuit 3;

[0045] The variable resistor VR has two ends connected to the other end of the first pin PIN1 and the other end of the second pin PIN2 respectively. A third resistor R3 is also connected in parallel between the first pin PIN1 and the second pin PIN2.

[0046] In a preferred embodiment of the present invention, the leakage detection circuit 3 includes:

[0047] The main chip MCU is provided with a plurality of voltage acquisition pins ADC, each of which corresponds to a voltage detection pin ADC of a leakage sensor unit 11, and also includes a plurality of ground pins GND, each of which corresponds to a ground pin GND of a leakage sensor unit;

[0048] CAN transceiver, the high-level signal pin CANH of the CAN transceiver is connected to the high-level signal pin CANH of the main chip, the low-level signal pin CANL of the CAN transceiver is connected to the low-level signal pin CANL of the main chip MCU, and the CAN transceiver is also connected to the battery management system;

[0049] The power pin POWER of the main chip is connected to the battery body BAT in the battery pack.

[0050] Specifically, in this embodiment, whether there is leakage is determined by the voltage output by the leakage sensor unit 11 .

[0051] In this embodiment, the first resistor R1 is a 100KΩ resistor, the power supply VCC provides a 5V DC power supply, and the third resistor R3 is a 500KΩ resistor. When there is no leakage, the variable resistor VR does not contact the liquid. At this time, the output voltage value = 5 / (510+100)*510≈4.18V. If the output voltage values ​​of each leakage sensor 11 collected by the leakage detection circuit 3 remain at 4.18V, it means that there is no leakage; if leakage occurs, the variable resistor VR is in contact with the liquid, the resistance value of the variable resistor VR changes, and the voltage value output by the leakage sensor unit collected by the leakage detection circuit is <<4.18V, which means that leakage occurs.

[0052] The collected voltage values ​​are converted into digital signals by the main chip MCU and then sent out by the CAN transceiver to the battery management system. This can match the battery management system of any manufacturer, improving the applicability of this device.

[0053] In a preferred embodiment of the present invention, the variable resistor VR in the liquid leakage sensor unit 11 faces the bottom of the box body 2 , and the first pin PIN1 and the second pin PIN2 extend vertically upward.

[0054] In this embodiment, the variable resistor VR is directed toward the bottom plate of the box body 2, so that it can contact the liquid in time when leakage occurs; and by adjusting the distance between the variable resistor VR and the bottom plate of the box body 2, leakage can be detected at different liquid heights, that is, when the distance is small, leakage can be detected when there is only a small amount of liquid on the bottom plate, and when the distance is large, leakage can be detected when there is more liquid on the bottom plate; the first pin PIN1 (voltage detection pin) and the second pin PIN2 (ground pin) are both vertically upward, which can, to a certain extent, prevent the pins from being contacted by the leakage due to excessive leakage, thereby avoiding short circuit and affecting the detection effect.

[0055] The above are only preferred embodiments of the present invention and do not limit the implementation methods and protection scope of the present invention. Those skilled in the art should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the contents of this specification and illustrations should be included in the protection scope of the present invention.

Claims

1. A device for detecting battery pack leakage, characterized in that: Comprising: A liquid leakage sensor module, arranged at the water inlet and outlet of the box body of the battery pack; A liquid leakage detection circuit, fixed to the inner wall of the box body, and electrically connected to the liquid leakage sensor module and the battery management system of the battery pack; The liquid leakage sensor module includes at least two liquid leakage sensor units; Each of the liquid leakage sensor units is respectively fixed to the water inlet and outlet of the box body through a fixing member; The voltage detection pin of the liquid leakage sensor unit is connected to the voltage acquisition pin of the liquid leakage detection circuit, and the ground pin of the liquid leakage sensor unit is connected to the ground pin of the liquid leakage detection circuit; The fixing member is in a "U" shape, and a redundant space is formed between the fixing member and the box body, and the liquid leakage sensor adjusts the distance between it and the box body in the redundant space.

2. The device according to claim 1, characterized in that The liquid leakage sensor unit includes: A first resistor, one end of the first resistor is used as a power supply pin and connected to a power supply, the other end of the first resistor is connected to one end of a second resistor and one end of a first pin, the other end of the second resistor is connected to one end of a first capacitor and the voltage acquisition pin, and the other end of the first capacitor is grounded; A second pin, one end of the second pin is connected to the ground pin of the liquid leakage detection circuit; A variable resistor, both ends of the variable resistor are respectively connected to the other end of the first pin and the other end of the second pin, and a third resistor is also connected in parallel between the first pin and the second pin.

3. The device according to claim 1, characterized in that The liquid leakage detection circuit includes: A main chip, the main chip has a plurality of the voltage acquisition pins, each of the voltage acquisition pins is respectively connected to the voltage detection pin of a liquid leakage sensor unit, and also includes a plurality of ground pins, each of the ground pins is respectively connected to the ground pin of a liquid leakage sensor unit; A CAN transceiver, the high-level signal pin of the CAN transceiver is connected to the high-level signal pin of the main chip, the low-level signal pin of the CAN transceiver is connected to the low-level signal pin of the main chip, and the CAN transceiver is also connected to the battery management system; The power supply pin of the main chip is connected to the battery body in the battery pack.

4. The device according to claim 1, characterized in that The fixing member is provided with a mounting hole, and the liquid leakage sensor unit is mounted in the mounting hole.

5. The device according to claim 2, characterized in that The variable resistor in the liquid leakage sensor unit faces the bottom of the box body, and the first pin and the second pin extend vertically upward.

6. A battery pack, characterized in that: Including the device for detecting liquid leakage of the battery pack according to any one of claims 1-5.

Images