Electronic nose system for detecting thermal runaway atmosphere of lithium battery

Abstract

The application belongs to the technical field of lithium battery thermal runaway detection, and specifically discloses an electronic nose system for detecting thermal runaway atmosphere of a lithium battery. The electronic nose system comprises a control platform, a semiconductor gas sensor array, a temperature and humidity sensor, and a VOC sensor. The first end of the control platform is connected to the temperature and humidity sensor, the second end is connected to the semiconductor gas sensor array, and the third end is connected to the VOC sensor. The semiconductor gas sensor array comprises a plurality of runaway gas sensors. The resistance of the runaway gas sensors changes in the presence of thermal runaway atmosphere, thereby detecting the thermal runaway atmosphere. The thermal runaway atmosphere comprises hydrogen, carbon monoxide, methane, and ethylene. The technical solution disclosed in the application is suitable for detecting the thermal runaway atmosphere of a lithium battery, has a wide range of applications, is highly stable, and can accurately and effectively detect the gas composition and concentration changes generated by a lithium battery in a thermal runaway state.

Description

Technical Field

[0001] This application belongs to the field of lithium battery thermal runaway detection technology, and more specifically, relates to an electronic nose system for detecting thermal runaway atmosphere in lithium batteries. Background Technology

[0002] In my country, the new energy electric vehicle market is experiencing rapid growth. However, the thermal runaway problem of lithium batteries has become a critical bottleneck that urgently needs to be overcome in its development and widespread application. This problem not only damages battery performance and lifespan, but in extreme cases, it can even lead to serious accidents such as fires or explosions, posing a significant threat to public safety. Traditional battery state monitoring technologies, such as monitoring parameters like voltage, current, internal resistance, internal pressure, and surface temperature, provide some means for real-time assessment of battery performance. However, in the early stages of battery thermal runaway, these parameters often change very little, making it difficult to provide timely and accurate early warning signals.

[0003] Recent studies have demonstrated that gas sensing technology exhibits significant advantages in early warning of thermal runaway in lithium-ion batteries. During thermal runaway, the chemical and electrochemical reactions occurring inside the battery release specific types of gases. Changes in the types and concentrations of these gases can serve as early indicators of the thermal runaway state. Semiconductor gas sensors detect gases based on the principle that the resistance of the gas-sensitive material changes before and after gas adsorption. They possess numerous outstanding advantages, including simple structure, high sensitivity, wide applicability, and ease of use.

[0004] Patent document CN119092862A discloses an electronic nose device for real-time monitoring of thermal runaway in lithium batteries, including a gas chamber, an exhaust device, a housing, a control system, and a gas sensor array plate encapsulated within the gas chamber. The exhaust device is connected to the gas chamber and fixed to the housing, and is electrically connected to the control system for automatic gas updates within the gas chamber. This electronic nose device has the advantages of simple structure, low cost, real-time monitoring and audible / visual warning for lithium battery thermal runaway, and ease of promotion. However, it still has shortcomings in terms of the applicable range and testing accuracy of gas detection. Its gas sensor array uses three CO sensors and three H2 sensors; however, during lithium battery thermal runaway, the gas composition is complex, including many organic or inorganic gases such as CH4 and C2H4, in addition to CO and H2. The limited variety of gas sensors leads to insufficient gas detection accuracy. Furthermore, there are many types of gas sensors, with resistance values ​​ranging from hundreds of ohms to tens of GΩ. Therefore, the data acquisition module needs to be optimized to improve the system's testing range. Utility Model Content

[0005] To address the shortcomings of existing technologies, the purpose of this application is to propose an electronic nose system for detecting thermal runaway atmosphere in lithium batteries. By expanding the types of gas sensors and combining them with temperature and humidity sensors and VOC sensors, this system aims to solve the problem of early warning of thermal runaway in lithium batteries of new energy vehicles.

[0006] To achieve the above objectives, in a first aspect, this application provides an electronic nose system for detecting thermal runaway atmosphere in lithium batteries, including a control platform, a semiconductor gas sensor array, a temperature and humidity sensor, and a VOC sensor; The temperature and humidity sensor is used to detect the temperature and humidity of the gas; The VOC sensor is used to detect the mass of the gas; The semiconductor gas sensor array includes multiple runaway gas sensors, whose resistance changes in the presence of a thermal runaway atmosphere, thereby detecting the thermal runaway atmosphere. The control platform is used to collect detection signals from the semiconductor gas sensor array, temperature and humidity sensor, and VOC sensor to determine whether the thermal runaway atmosphere of the lithium battery exceeds the threshold. The control platform is connected to the temperature and humidity sensor at one end, the semiconductor gas sensor array at the other end, and the VOC sensor at the third end.

[0007] Preferably, the runaway gas sensor includes a Figaro TGS2600 sensor and / or a Figaro TGS2611 sensor.

[0008] Preferably, it also includes a gear switching module connected in series with the semiconductor gas sensor array; the gear switching module is used to adjust the detection signal sensitivity of the semiconductor gas sensor array by changing its own resistance or amplifying the current signal.

[0009] As a further preferred embodiment, the gear shifting module includes a parallel current amplification path and multiple resistance switching paths; the current amplification path is composed of a relay and a current amplifier connected in series, used to amplify the current signal, i.e., the detection signal of the semiconductor gas sensor array; each resistance switching path is composed of an analog switch and a matching resistor connected in series, used to change the resistance of the gear shifting module itself.

[0010] Preferably, the system further includes a heating controller connected to a fourth terminal of the control platform, the heating controller being thermally integrated with the semiconductor gas sensor array; the control platform is also used to control the temperature of the heating controller.

[0011] As a further preferred embodiment, the system also includes a power management unit connected to a fifth terminal of the control platform. The power management unit has a first voltage output terminal connected to the semiconductor gas sensor array, a second voltage output terminal connected to the temperature and humidity sensor, a third voltage output terminal connected to the VOC sensor, and a fourth voltage output terminal connected to the heating controller. The power management unit is used to provide voltage to the semiconductor gas sensor array, the temperature and humidity sensor, the VOC sensor, and the heating controller. The control platform is also used to adjust the voltage provided by the power management unit.

[0012] Preferably, the system also includes a host computer, and the sixth terminal of the control platform is connected to the host computer; the host computer is used to determine whether the thermal runaway atmosphere exceeds the threshold based on the detection signals of the semiconductor gas sensor array, the temperature and humidity sensor and the VOC sensor, and to issue an indication signal.

[0013] Preferably, it also includes a storage unit, and the seventh terminal of the control platform is connected to the interaction terminal of the storage unit.

[0014] As a further preferred embodiment, the storage unit is an EEPROM chip.

[0015] Preferably, the control platform is an ARM processor computing control platform.

[0016] Overall, the technical solutions conceived in this application have the following beneficial effects compared with the prior art: 1. The semiconductor gas sensor array of this application integrates runaway gas sensors capable of detecting hydrogen, carbon monoxide, methane, and ethylene, thereby improving the detection range and accuracy of runaway gases. It is suitable for detecting thermal runaway atmospheres in lithium batteries. The entire system has a wide range of applications and high operational stability, enabling accurate and effective detection of gas composition and concentration changes generated by lithium batteries under thermal runaway conditions. It possesses significant advantages such as a wide testing range, accurate measurement, and excellent sensitivity. In the field of new energy vehicles, this system plays a crucial role, providing strong support for ensuring the safe and stable operation of new energy vehicles. 2. This application is preferably built on an ARM processor computing and control platform based on the Cortex-M3 core; the system not only has stable data transmission function, but also can precisely adjust the control parameters through the host computer; the system adopts wired transmission, the data transmission process is stable and reliable, has strong anti-interference ability, can adapt to the complex electromagnetic environment and mechanical vibration environment inside the car, and ensures normal operation under various working conditions; 3. The electronic nose system of this application preferably has a built-in storage unit, which can be used to store control parameters. This feature allows the system to continue to use the previously stored control parameters after a power outage and restart, ensuring the continuity and stability of system operation. 4. The electronic nose system of this application preferably uses a gear switching module, thereby greatly expanding the test range of the sensor array; by using the voltage divider method and the co-current amplifier method to detect the sensor resistance, the detection range can be extended to 10Ω~100GΩ, thereby greatly improving the test range and test accuracy of the sensor. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the electronic nose system of this application; Figure 2 This is a schematic diagram of the gear shifting module in Embodiment 1 of this application. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0019] Furthermore, throughout this specification, references to "an embodiment"; "an embodiment," "an example," or similar language indicate that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment of this application. Therefore, the appearance of the phrase "in one embodiment;" throughout this specification, along with "in one embodiment," "in some embodiments," and similar language, may, but not necessarily, refer to the same embodiment.

[0020] The electronic nose system for detecting the thermal runaway atmosphere of lithium batteries involved in this application is designed to accurately meet the need for detecting various gases and gas mixtures generated during the thermal runaway process of lithium batteries. Figure 1 As shown, the electronic nose system includes a control platform, a semiconductor gas sensor array 4, a temperature and humidity sensor 5, a VOC sensor 6, and a heating controller 7; the heating controller 7 is thermally integrated with the semiconductor gas sensor array 6 to control the ambient temperature during detection; in some embodiments, the control platform uses an ARM processor to compute the control platform 2. The control platform is connected to a temperature and humidity sensor 5 at its first end, a semiconductor gas sensor array 4 at its second end, a VOC sensor 6 at its third end, and a heating controller 7 at its fourth end. The semiconductor gas sensor array includes multiple runaway gas sensors. The resistance of the runaway gas sensors changes in the presence of a thermal runaway atmosphere, thereby detecting the thermal runaway atmosphere. The runaway gas sensors include a hydrogen sensor, a carbon monoxide sensor, a methane sensor, and an ethylene sensor. Among them, the hydrogen sensor can be a Figaro TGS2600 sensor or a self-made sensor in the laboratory (Zhou Shiyu. Design and Performance Research of Semiconductor Hydrogen Sensitive Materials [D]. Zhejiang University, 2024. DOI:10.27461 / d.cnki.gzjdx). (2024.001900) The carbon monoxide sensor can be a Figaro TGS2600 sensor or a self-made sensor in the laboratory (Wei Wei. Preparation and performance study of room temperature heterojunction thin film carbon monoxide sensor [D]. Hubei University, 2023. DOI:10.27130 / d.cnki.ghubu.2023.000602.), the methane sensor is a Figaro TGS2611 sensor, and the ethylene sensor is a self-made sensor in the laboratory (Li Chunjie. Research on oxide semiconductor-based ethylene gas sensor [D]. Shandong University of Technology, 2024. DOI:10.27276 / d.cnki.gsdgc. 2024.001062. or Sun Jie. Research on WSe2 / rGO and ZnO / CNFs composite film ethylene gas sensor [D]. University of Electronic Science and Technology of China, 2021. DOI:10.27005 / (d.cnki.gdzku.2021.003868.); Since sometimes a single sensor is sensitive to more than one type of gas, for example, the Figaro TGS2600 sensor is sensitive to both hydrogen and carbon monoxide, there are cases where the same device can be used as a sensor for two types of runaway gases.

[0021] VOC sensor 6 is used to detect gas quality; the control platform is used to collect the detection signals from semiconductor gas sensor array 4, temperature and humidity sensor 5 and VOC sensor 6, and at the same time to control the temperature of heating controller 7.

[0022] In some embodiments, a power management unit 1 is connected to the fifth terminal of the control platform. The first voltage output terminal of the power management unit 1 is connected to the semiconductor gas sensor array 4, the second voltage output terminal is connected to the temperature and humidity sensor 5, the third voltage output terminal is connected to the VOC sensor 6, and the fourth voltage output terminal is connected to the heating controller 7. The power management unit 1 is used to provide corresponding voltages to the semiconductor gas sensor array 4, the temperature and humidity sensor 5, the VOC sensor 6, and the heating controller 7. The control platform is also used to adjust the voltage provided by the power management unit.

[0023] In some embodiments, a host computer 8 connected to the sixth terminal of the control platform is also included. The host computer 8 is responsible for analyzing and displaying the data from the gas sensor array 4, VOC sensor 6, temperature and humidity sensor 5, and heating controller 7. Specifically, a detection model needs to be established based on the type of lithium battery and the runaway gas sensor used, and a threshold is set (for example, the method in patent document CN120724116A can be referred to). When the detection data of two or more of the semiconductor gas sensor array, temperature and humidity sensor, and VOC sensor exceed the threshold, it is determined that the thermal runaway atmosphere exceeds the threshold, and the host computer 8 gives an indication signal to trigger an alarm. At the same time, the detection signals of each sensor are also displayed on the display screen connected to the host computer 8 so that professionals can conduct in-depth analysis of the gas composition and related characteristics.

[0024] In some embodiments, a storage unit 9 connected to a seventh terminal of the control platform is also included. The storage unit preferably uses an EEPROM chip and can be used to store historical detection data.

[0025] In some embodiments, a gear switching module 3 connected in series with the semiconductor gas sensor array is also provided. The gear switching module 3 is used to adjust the sensitivity of the semiconductor gas sensor array by adjusting its own resistance or by connecting it to a current amplifier. In some embodiments, the gear switching module includes a current amplification path connected in parallel and multiple resistance switching paths. The current amplification path is composed of a relay and a current amplifier connected in series, and is used to amplify the detection signal of the semiconductor gas sensor array. Each resistance switching path is composed of an analog switch and a matching resistor connected in series, and is used to change the own resistance of the gear switching module. Since the semiconductor gas sensor array is connected in series with it, when the resistance of the gear switching module increases, the voltage drop across the corresponding semiconductor gas sensor array will decrease (and vice versa). When the gear switching module is used to amplify the current signal, the detection signal of the corresponding semiconductor gas sensor array will be amplified, and it will be more accurate when the current signal is too weak. The gear switching module changing its own resistance or amplifying the current signal is equivalent to changing the gear of the detection signal of the semiconductor gas sensor array.

[0026] The embodiments of this application are implemented based on the technical solution of this application, and detailed implementation methods and processes are given. However, the protection scope of this application is not limited to the following embodiments. The process parameters in the following embodiments that do not specify specific conditions are generally based on conventional conditions.

[0027] The endpoints and any values ​​of the ranges disclosed in this application are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this application.

[0028] Example 1 The structural schematic diagram of Example 1 is shown below. Figure 1 As shown, the power management unit 1 includes several power chips (AMS1117-3.3, XC6202P182MR) and related circuits. It receives 5V power from the computer via USB-TYPE-C and converts it into 5V, 3.3V, and 1.8V to provide corresponding power to various modules of the system. The ARM processor computing control platform 2 can accept and process raw data from the semiconductor gas sensor array 4, temperature and humidity sensor 5, and VOC sensor 6. At the same time, it controls the gear switching module 3 and heating controller 7 to perform specified operations, and reads or stores data through the storage unit 9 in a timely manner, uploads data to the host computer 8, and interacts with it. Semiconductor gas sensor array 4 contains eight semiconductor gas sensors selected from Figaro TGS2600 (for detecting hydrogen and carbon monoxide), Figaro TGS2611 (for detecting methane), Winsen MP-5 (for propane), Winsen WSP2110 (for detecting toluene, formaldehyde, benzene, alcohol, and acetone), and four laboratory-made gas sensors. The room-temperature heterojunction thin-film carbon monoxide sensor was fabricated according to the method described in the literature "Preparation and Performance Study of Room-Temperature Heterojunction Thin-Film Carbon Monoxide Sensor [D]" (Wei Wei, Hubei University, 2023. DOI:10.27130 / d.cnki.ghubu.2023.000602.). The semiconductor hydrogen sensor was fabricated according to the method described in the literature "Design and Performance Study of Semiconductor Hydrogen Sensitive Materials [D]" (Zhou Shiyu, Zhejiang University, 2024. DOI:10.27461 / d.cnki.gzjdx.2024.). 001900); The oxide semiconductor-based ethylene gas sensor was fabricated according to the method described in the literature "Research on Oxide Semiconductor-based Ethylene Gas Sensor [D]" (Li Chunjie. Shandong University of Technology, 2024. DOI:10.27276 / d.cnki.gsdgc.2024.001062.); The composite membrane ethylene gas sensor was fabricated according to the method described in the literature "Research on WSe2 / rGO and ZnO / CNFs Composite Membrane Ethylene Gas Sensor [D]" (Sun Jie. University of Electronic Science and Technology of China, 2021. DOI:10.27005 / d.cnki.gdzku.2021.003868.).

[0029] Temperature and humidity sensor 5 is the Sensirin SHT31, which can directly obtain temperature and humidity parameters through calculation; VOC sensor 6 is the Sensirin SGP40, which can directly assess indoor air quality through built-in algorithm. The ARM processor computing control platform 2 uses PWM waves to regulate the heating voltage of the heating controller 7, with a voltage range of 0-5V. The power of the heating resistance wire on the corresponding semiconductor gas sensor is 0-0.25W, which can control the sensor's operating temperature between 30 and 300℃. like Figure 2 As shown, the gear switching module 3 has three gears: 10Ω-100KΩ, 100KΩ-1GΩ, and 1GΩ-100GΩ. The gears are switched by the first analog switch, the second analog switch, and the relay, respectively. In this system, the first analog switch is connected in series with a 1KΩ matching resistor, the second analog switch is connected in series with a 10MΩ matching resistor, and the relay is connected in series with a current amplifier. When the resistance is less than 1GΩ, the resistance of the semiconductor electronic sensor is detected by a voltage divider method: either the first or second analog switch is connected, the relay is disconnected, and the 1KΩ and 10MΩ matching resistors are used to divide the voltage across the sensor. An ADS114S08 sampling chip is used to collect the voltage across the semiconductor electronic sensor, and the resistance value of the semiconductor electronic sensor is finally calculated. When the detection resistance of the semiconductor electronic sensor is greater than 1GΩ, the current reaches the nA level, and the resistance of the semiconductor electronic sensor is detected by a co-amplifier method: the relay is connected, the first and second analog switches are disconnected, and two operational amplifiers, OPA365AIDBVR and AS321KTR-E1, are connected in series as a current amplifier to amplify the weak current signal of the semiconductor electronic sensor to the mA level. Finally, the sampling chip is used to collect the current value, and the sensor resistance value is obtained. This method can greatly expand the sensor signal acquisition range and test accuracy.

[0030] The host computer 8 is a self-developed human-machine interface used to display the sensor data after acquisition and processing; the storage unit 9 uses the M24C02-WMN6TP, which is a serial electrically erasable programmable read-only memory (EEPROM) chip with a storage capacity of 2Kbit, which can store up to 256 bytes of detection data.

[0031] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An electronic nose system for lithium battery thermal runaway atmosphere detection, characterized in that, The control platform, the semiconductor gas sensor array, the temperature and humidity sensor, and the VOC sensor are connected in series. The temperature and humidity sensor is used for detecting the temperature and humidity of the gas. The VOC sensor is used for detecting the quality of the gas. The semiconductor gas sensor array includes a plurality of runaway gas sensors, which change in resistance in the presence of a thermal runaway atmosphere, thereby detecting the thermal runaway atmosphere. The control platform is used for collecting the detection signals of the semiconductor gas sensor array, the temperature and humidity sensor, and the VOC sensor, so as to determine whether the thermal runaway atmosphere of the lithium battery exceeds a threshold value.

2. The electronic nose system of claim 1, wherein, The runaway gas sensor includes a Figaro TGS2600 sensor and / or a Figaro TGS2611 sensor.

3. The electronic nose system of claim 1, wherein, The gear shifting module is connected in series with the semiconductor gas sensor array, and is used for adjusting the sensitivity of the detection signal of the semiconductor gas sensor array by changing the resistance of the gear shifting module or amplifying the current signal.

4. The electronic nose system of claim 3, wherein, The gear shifting module includes a current amplification path and a plurality of resistance switching paths connected in parallel.

5. The electronic nose system of claim 1, wherein, The gear shifting module further includes a heating controller connected to the fourth end of the control platform, and the heating controller is thermally connected with the semiconductor gas sensor array.

6. The electronic nose system of claim 5, wherein, The power management unit is connected to the fifth end of the control platform, and is used for providing voltages to the semiconductor gas sensor array, the temperature and humidity sensor, the VOC sensor, and the heating controller.

7. The electronic nose system of claim 1, wherein, The upper computer is connected to the sixth end of the control platform, and is used for determining whether the thermal runaway atmosphere exceeds a threshold value according to the detection signals of the semiconductor gas sensor array, the temperature and humidity sensor, and the VOC sensor, and sending an indication signal.

8. The electronic nose system of claim 1, wherein, The storage unit is connected to the seventh end of the control platform, and is used for storing historical detection data.

9. The electronic nose system of claim 8, wherein, The control platform is an ARM processor computing control platform.

10. The electronic nose system of claim 1, wherein, ​

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