Battery cell pressure detection device based on BMS

Abstract

The utility model relates to a battery cell pressure detection device based on a BMS, comprising a BMS system, the BMS system comprises a sensor module, a data acquisition module, a control unit, a storage unit and a communication unit, the battery cell pressure detection device also comprises a plurality of pressure sensors, the pressure sensors comprise film type pressure sensors, the data acquisition module comprises a pressure acquisition module, and the control unit is connected with the storage unit. The plurality of film type pressure sensors are electrically connected with a pressure acquisition module; the BMS system is connected with a battery pack, the battery pack comprises a plurality of battery cells, the plurality of battery cells are averagely grouped to form string groups, the plurality of battery cells in one string group are connected in series, and two sides of one string group are provided with film type pressure sensors; the battery cells are fixedly connected with the adjacent battery cells, and the film type pressure sensors are fixed with the battery cells. According to the utility model, the film type pressure sensors are respectively arranged on two sides of one string group, detection signals are acquired through the pressure acquisition module, and whether the battery cell is expanded or not is reflected through pressure.

Description

Technical Field

[0001] This utility model relates to the field of battery management systems, specifically to a cell pressure detection device based on a BMS. Background Technology

[0002] Existing battery management systems (BMS) primarily rely on parameters such as voltage, temperature, and current to monitor the battery's operating status and ensure the safe and efficient operation of the battery system. However, during charging and discharging, especially under high load conditions, the physical pressure between battery cells may change significantly. This pressure change may be caused by factors such as battery expansion or abnormal thermal runaway. If it is not monitored and responded to in a timely manner, it may lead to a decline in battery performance or even cause safety accidents.

[0003] However, most current BMS do not directly monitor the physical pressure between battery cells, and there are few technical solutions for battery pressure monitoring on the market, and they also suffer from high costs and integration difficulties.

[0004] Therefore, there is an urgent need for a device that can introduce a real-time battery pressure monitoring mechanism into the BMS to provide a hardware foundation for optimizing battery management. Summary of the Invention

[0005] To address the problem that existing battery management systems cannot detect the physical pressure between battery cells, this invention proposes a battery cell pressure detection device based on a BMS. Thin-film pressure sensors are installed on both sides of a string, and the detection signal is acquired through a pressure acquisition module. The pressure reflects whether the battery cell has undergone changes such as expansion.

[0006] To achieve the above objectives, this utility model proposes a cell pressure detection device based on a BMS, comprising a BMS system, which includes a sensor module, a data acquisition module, a control unit, a storage unit, and a communication unit. The sensor module includes a voltage sensor, a current sensor, and a temperature sensor, which are respectively connected to the data acquisition module. The output of the data acquisition module is connected to the control unit. The device also includes multiple pressure sensors, including thin-film pressure sensors. The data acquisition module includes a pressure acquisition module, and the multiple thin-film pressure sensors are electrically connected to the pressure acquisition module.

[0007] The BMS system is connected to a battery pack, which includes multiple cells. The multiple cells are evenly grouped into a series group. Multiple cells in a series group are connected in series. Thin-film pressure sensors are provided on both sides of a series group.

[0008] The battery cell is fixedly connected to the adjacent battery cells, and the thin-film pressure sensor is fixed to the battery cell.

[0009] Furthermore, the control unit includes an NXPS32K146 chip, and the ADC port of the NXPS32K146 chip is connected to a voltage sensor, a current sensor, a temperature sensor and multiple pressure acquisition modules through a data acquisition module.

[0010] The NXPS32K146 chip communicates with the memory unit. Based on the ARM Cortex-M4F core, the NXPS32K146 chip supports floating-point arithmetic (FPU), making it suitable for complex algorithm processing (such as battery state estimation). It integrates multiple 12-bit ADCs, timers, PWM, and CAN FD (Flexible Data Rate) to meet the needs of multi-sensor data acquisition and high-speed communication.

[0011] Furthermore, the communication unit includes a CAN FD module, and the control unit is connected to a host computer via the CAN FD module.

[0012] The host computer includes the vehicle main control system and the cloud platform.

[0013] Furthermore, the pressure acquisition module includes a signal processing circuit, which includes a pull-up resistor R1, a capacitor C2, and a comparator LM393. The output terminal of the thin-film pressure sensor is connected to the output terminal of the comparator LM393 via the pull-up resistor R1 and the capacitor C2. The output terminal of the LM393 is connected to the ADC port of the NXPS32K146 chip.

[0014] Thin-film pressure sensors operate based on the piezoresistive effect. When deformed under pressure, they output an electrical signal. This signal is filtered by pull-up resistor R1 and capacitor C2, processed by comparator LM393, and finally received by NXPS32K146 chip.

[0015] Furthermore, the output of the comparator LM393 is also connected to an alarm circuit. The alarm circuit includes a potentiometer, a resistor R2, a light-emitting diode D1, and a resistor R3. The potentiometer and the resistor R2 are connected in series to form a voltage divider circuit. One side of the potentiometer is connected to the inverting terminal of the comparator LM393, and the other side is connected to the output terminal of the comparator LM393 via the resistor R2. The positive terminal of the light-emitting diode D1 is connected to the resistor R2, and the negative terminal of the light-emitting diode D1 is grounded via the resistor R3.

[0016] The greater the deformation of a thin-film pressure sensor, the greater the output voltage, which also reflects whether the battery cell is deformed.

[0017] When the output of comparator LM393 is greater than the output via potentiometer, the battery cell undergoes significant deformation, at which point LED D1 illuminates. This facilitates the removal of the battery string for maintenance.

[0018] The beneficial effects of this utility model through the above technical solution are as follows:

[0019] This invention enables the monitoring of physical pressure between multiple battery cells. Thin-film pressure sensors are installed on both sides of the battery string, combined with a pressure acquisition module and a control unit, to achieve real-time monitoring of the physical pressure of the cells, providing a hardware foundation for effectively reflecting the deformation state of the cells. Through joint analysis of pressure data with parameters such as voltage and temperature, cell anomalies can be identified in advance, avoiding risks such as battery performance degradation, short circuits, and even thermal runaway. Attached Figure Description

[0020] Figure 1 This is a structural diagram of a cell pressure detection device based on BMS according to this utility model;

[0021] Figure 2 This is a circuit diagram of a cell pressure detection device based on BMS according to this utility model;

[0022] Figure 3 This is a circuit diagram of the pressure acquisition module of a cell pressure detection device based on BMS according to this utility model.

[0023] Reference numerals: 1 is the control unit, 2 is the storage unit, 3 is the thin-film pressure sensor, 4 is the pressure acquisition module, 5 is the battery cell, 6 is the communication unit, and 8 is the alarm circuit. Detailed Implementation

[0024] Example 1

[0025] like Figures 1-3 As shown, a battery cell pressure detection device based on a battery management system (BMS) includes a BMS system. The BMS system includes a sensor module, a data acquisition module, a control unit 1, a storage unit 2, and a communication unit 6. The sensor module includes a voltage sensor, a current sensor, and a temperature sensor. The voltage sensor, current sensor, and temperature sensor are respectively connected to the data acquisition module. The output terminal of the data acquisition module is connected to the control unit 1. The device also includes multiple pressure sensors, including thin-film pressure sensors 3. The data acquisition module includes a pressure acquisition module 4. The multiple thin-film pressure sensors 3 are electrically connected to the pressure acquisition module 4.

[0026] The BMS system is connected to a battery pack, which includes multiple battery cells 5. The multiple battery cells 5 are evenly grouped into a series group. The multiple battery cells 5 in a series group are connected in series. A thin film pressure sensor 3 is provided on both sides of a series group.

[0027] The battery cell 5 is fixedly connected to the adjacent battery cell 5, and the thin-film pressure sensor 3 is fixed to the battery cell 5.

[0028] The control unit 1 includes an NXPS32K146 chip, and the ADC port of the NXPS32K146 chip is connected to a voltage sensor, a current sensor, a temperature sensor and multiple pressure acquisition modules 4 through a data acquisition module.

[0029] The NXPS32K146 chip is connected to memory unit 2.

[0030] The communication unit 6 includes a CAN FD module, and the control unit 1 is connected to a host computer via the CAN FD module.

[0031] The pressure acquisition module 4 includes a signal processing circuit, which includes a pull-up resistor R1, a capacitor C2, and a comparator LM393. The output terminal of the thin-film pressure sensor 3 is connected to the output terminal of the comparator LM393 via the pull-up resistor R1 and the capacitor C2. The output terminal of the LM393 is connected to the ADC port of the NXPS32K146 chip.

[0032] The output of the comparator LM393 is also connected to an alarm circuit 8. The alarm circuit 8 includes a potentiometer, a resistor R2, a light-emitting diode D1, and a resistor R3. The potentiometer and the resistor R2 are connected in series to form a voltage divider circuit. One side of the potentiometer is connected to the inverting terminal of the comparator LM393, and the other side is connected to the output terminal of the comparator LM393 through the resistor R2. The positive terminal of the light-emitting diode D1 is connected to the resistor R2, and the negative terminal of the light-emitting diode D1 is grounded through the resistor R3.

[0033] In this embodiment, 96 battery cells 5 are set, with 6 battery cells 5 forming a series group, for a total of 16 series groups. Each series group is equipped with two thin-film pressure sensors 3, for a total of 32 thin-film pressure sensors 3 are set. The corresponding pressure acquisition modules 4 are 32, and the alarm circuits 8 are 32.

[0034] During operation, the thin-film pressure sensor 3 is fixed to the battery cell 5, and the battery cell 5 is fixedly connected to the adjacent battery cells 5. When the battery cell 5 changes due to expansion, abnormal thermal runaway, or other reasons, the distance between the battery cell 5 and the adjacent battery cells 5 will decrease, resulting in increased pressure. The thin-film pressure sensor 3 will further deform under pressure, and its output electrical signal will also change accordingly.

[0035] The pressure signal is filtered by pull-up resistor R1 and capacitor C2, then processed by comparator LM393 and output to the ADC port of NXPS32K146 chip. NXPS32K146 chip uploads the voltage signal to the vehicle's main control system or cloud platform through CAN FD module to realize remote monitoring and data analysis.

[0036] At the same time, the signal is sent to the alarm circuit 8. The potentiometer resistance is adjusted in advance so that when the battery cell 5 is normal, the voltage output by the comparator LM393 is less than the voltage applied to the reverse terminal of the comparator LM393 after voltage division by the potentiometer, and the LED D1 does not light up.

[0037] When cell 5 experiences abnormal pressure, the voltage output by comparator LM393 exceeds the voltage after potentiometer division, causing the positive terminal voltage of LED D1 to exceed the negative terminal voltage, thus illuminating the LED. This allows staff to quickly pinpoint which cell 5 in the series has malfunctioned.

[0038] Example 2

[0039] Based on the BMS-based cell pressure detection device in Example 1, this example describes the management of the battery pack in conjunction with the BMS:

[0040] Firstly, the cell pressure detection device enables real-time monitoring of the pressure of cell 5 and data transmission.

[0041] In the BMS, the NXPS32K146 chip analyzes the battery pack status by integrating voltage, temperature, current and pressure data to determine the health status of the battery pack.

[0042] When the cell pressure value of a certain string exceeds the preset threshold, the BMS will alarm the host computer and adjust the charging and discharging strategy to ensure the safe operation of the battery pack.

[0043] The charging and discharging strategies include reducing the charging and discharging speed and disconnecting the battery pack.

[0044] The embodiments described above are merely preferred embodiments of this utility model and are not intended to limit the scope of implementation of this utility model. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the patent claims of this utility model should be included within the scope of the patent application of this utility model.

Claims

1. A BMS-based cell pressure detection device, comprising a BMS system, the BMS system comprising a sensor module, a data acquisition module, a control unit (1), a storage unit (2) and a communication unit (6), the sensor module comprising a voltage sensor, a current sensor and a temperature sensor, the voltage sensor, the current sensor and the temperature sensor being connected to the data acquisition module respectively, an output end of the data acquisition module being connected to the control unit (1), characterized in that, Also include a plurality of pressure sensors, the pressure sensor includes a thin film pressure sensor (3), the data acquisition module includes a pressure acquisition module (4), a plurality of the thin film pressure sensor (3) and pressure acquisition module (4) are electrically connected; The BMS system is connected with a battery pack, the battery pack includes a plurality of battery cells (5), a plurality of battery cells (5) are evenly grouped to form a string group, a plurality of battery cells (5) in one string group are connected in series, and both sides of one string group are provided with a thin film pressure sensor (3); The battery cell (5) is fixedly connected with the adjacent battery cell (5), and the thin film pressure sensor (3) is fixed with the battery cell (5).

2. The BMS-based cell pressure detection device of claim 1, wherein, The control unit (1) includes an NXPS32K146 chip, and the ADC port of the NXPS32K146 chip is connected with a voltage sensor, a current sensor, a temperature sensor and a plurality of pressure acquisition modules (4) through a data acquisition module; The NXPS32K146 chip is in communication connection with the storage unit (2).

3. The BMS-based cell pressure detection device of claim 1, wherein, The communication unit (6) includes a CAN FD module, and the control unit (1) is in communication connection with an upper computer through the CAN FD module.

4. The BMS-based cell pressure detection device of claim 2, wherein, The pressure acquisition module (4) includes a signal processing circuit, the signal processing circuit includes a pull-up resistor R1, a capacitor C2 and a comparator LM393, the output end of the thin film pressure sensor (3) is connected with the output end of the comparator LM393 through the pull-up resistor R1 and the capacitor C2, and the output end of the LM393 is connected with the ADC port of the NXPS32K146 chip.

5. The BMS-based cell pressure detection device of claim 4, wherein, The output end of the comparator LM393 is also connected with an alarm circuit (8), the alarm circuit (8) includes a potentiometer, a resistor R2, a light emitting diode D1 and a resistor R3, the potentiometer and the resistor R2 are connected in series to form a voltage dividing circuit, one side of the potentiometer is connected with the reverse end of the comparator LM393, the other side is connected with the output end of the comparator LM393 through the resistor R2, the anode of the light emitting diode D1 is connected with the resistor R2, and the cathode of the light emitting diode D1 is grounded through the resistor R3.

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