Battery Leakage Gas Monitoring Device and Method

Abstract

The present invention provides a battery leakage gas monitoring device and method, which relates to the technical field of battery safety management, and includes: a gas collection module for sampling the gas in the space around the battery to obtain a gas to be measured; a gas ionization module for ionizing the gas molecules in the gas to be measured to obtain gas ions; a magnetic confinement module for using a magnetic field to capture the gas ions; the gas ions perform Larmor precession in the magnetic field; a microwave module for applying microwaves to the gas ions captured by the magnetic field; a power detection module for detecting the microwave absorption power when the microwaves interact with the gas ions; and a data analysis module for determining the gas components contained in the gas to be measured and the concentration of the gas components based on the microwave absorption power. The device and method provided by the present invention achieve comprehensive, rapid and accurate monitoring of the leaked gas in the battery.

Description

Technical Field

[0001] The present invention relates to the technical field of battery safety management, and in particular to a battery leakage gas monitoring device and method. Background Art

[0002] With the rapid development of new energy vehicles, energy storage systems and consumer electronics, lithium batteries are being used more and more widely, but the risk of thermal runaway, combustion and even explosion is also increasing. On the one hand, in thermal runaway, high temperatures in lithium-ion batteries will cause the decomposition of the negative electrode SEI film (Solid Electrolyte Interphase), the decomposition of the positive electrode active material and the oxidation decomposition of the electrolyte, resulting in a large amount of gas, causing the gas pressure inside the lithium-ion battery to rise sharply, causing the battery to explode, and a large amount of high-temperature, flammable and toxic gas is released from the battery, which will seriously threaten the safety of equipment and property.

[0003] The battery leakage gas monitoring device in the related art can usually only monitor one specific type of gas, and the monitoring sensitivity is low and the response time is long.

[0004] Therefore, how to comprehensively, quickly and accurately monitor the gas leakage in the battery and improve the safety of the battery has become a technical problem that needs to be urgently solved in the industry. Summary of the invention

[0005] The present invention provides a battery leakage gas monitoring device and method, which are used to solve the technical problem of how to comprehensively, quickly and accurately monitor the gas leaked in the battery.

[0006] The present invention provides a battery leakage gas monitoring device, comprising:

[0007] A gas collection module is used to sample the gas in the space around the battery to obtain the gas to be tested;

[0008] A gas ionization module, used for ionizing gas molecules in the gas to be measured to obtain gas ions;

[0009] A magnetic confinement module, used for capturing the gas ions by using a magnetic field; the gas ions undergo Larmor precession in the magnetic field;

[0010] a microwave module, for applying microwaves to the gas ions trapped by the magnetic field;

[0011] A power detection module, used for detecting microwave absorption power when the microwave interacts with the gas ions;

[0012] The data analysis module is used to determine the gas components contained in the gas to be measured and the concentrations of the gas components based on the microwave absorption power.

[0013] In some embodiments, the device further includes a gas transmission pipeline and a vacuum module;

[0014] A first end of the gas transmission pipeline is connected to the gas collection module, and a second end is connected to the vacuum module; the gas transmission pipeline sequentially passes through the magnetic confinement module and the microwave module along the direction from the first end to the second end;

[0015] The vacuum module is used to generate a negative pressure at the second end, so that the gas to be measured flows out of the gas collection module and enters the vacuum module.

[0016] In some embodiments, the gas ionization module includes a first electrode and a second electrode;

[0017] The first electrode and the second electrode are arranged in parallel along the flowing direction of the gas to be measured in the gas transmission pipeline;

[0018] An electric field is generated between the first electrode and the second electrode; the electric field is used to ionize the gas molecules into gas ions.

[0019] In some embodiments, the magnetic confinement module includes a first Helmholtz coil and a second Helmholtz coil;

[0020] The first Helmholtz coil and the second Helmholtz coil are arranged perpendicular to each other along the flowing direction of the gas to be measured in the gas transmission pipeline;

[0021] A magnetic field is generated between the first Helmholtz coil and the second Helmholtz coil; the magnetic field is used to capture the gas ions.

[0022] In some embodiments, the data analysis module is used for:

[0023] Determine a spectral diagram of the microwave absorption power; the spectral diagram is used to record the correspondence between the microwave absorption power and the microwave frequency;

[0024] Determine at least one maximum value of the microwave absorption power in the spectral diagram;

[0025] Compare the microwave frequency corresponding to the maximum value of the microwave absorption power with the Larmor precession frequencies of the gas ions corresponding to each characteristic gas component;

[0026] When the microwave frequency is consistent with the Larmor precession frequency of the gas ions corresponding to any characteristic gas component, determine that the gas to be measured contains the any characteristic gas component.

[0027] In some embodiments, the data analysis module is used for:

[0028] Based on the maximum value of the microwave absorption power and the corresponding relationship between the microwave absorption power of any one of the characteristic gas components and the gas concentration, determine the gas concentration of any one of the characteristic gas components in the gas to be measured.

[0029] In some embodiments, the microwave module is used for:

[0030] Determine the Larmor precession frequencies of the gas ions corresponding to multiple characteristic gas components;

[0031] Based on the minimum value and the maximum value of the Larmor precession frequencies of the gas ions corresponding to the multiple characteristic gas components, determine the microwave frequency scanning range;

[0032] Based on the microwave frequency scanning range and the microwave frequency scanning step, apply microwaves with different microwave frequencies to the gas ions trapped by the magnetic field.

[0033] The present invention provides a method for monitoring battery leakage gas, which is applied to the battery leakage gas monitoring device described above, and includes:

[0034] Based on the microwave frequency scanning range and the microwave frequency scanning step, control the microwave module to apply microwaves with different microwave frequencies to the gas ions trapped by the magnetic field in the magnetic confinement module; the microwave frequency scanning range is determined based on the Larmor precession frequencies of the gas ions corresponding to multiple characteristic gas components;

[0035] Obtain a spectrogram of the microwave absorption power when the microwave interacts with the gas ions sent by the power detection module; the spectrogram is used to record the corresponding relationship between the microwave absorption power and the microwave frequency;

[0036] Determine at least one maximum value of the microwave absorption power in the spectrogram;

[0037] Compare the microwave frequency corresponding to the maximum value of the microwave absorption power with the Larmor precession frequencies of the gas ions corresponding to each characteristic gas component;

[0038] When the microwave frequency is consistent with the Larmor precession frequency of the gas ions corresponding to any one of the characteristic gas components, determine that the gas to be measured contains any one of the characteristic gas components;

[0039] Based on the maximum value of the microwave absorption power and the corresponding relationship between the microwave absorption power of any one of the characteristic gas components and the gas concentration, determine the gas concentration of any one of the characteristic gas components in the gas to be measured.

[0040] The present invention provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the battery leakage gas monitoring method described above is implemented.

[0041] The present invention provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the battery leakage gas monitoring method described above is implemented.

[0042] For the battery leakage gas monitoring device and method provided by the present invention, a gas collection module is used to sample the gas in the space around the battery to obtain the gas to be measured; a gas ionization module is used to ionize the gas molecules in the gas to be measured to obtain gas ions; a magnetic confinement module is used to capture the gas ions by using a magnetic field; the gas ions perform Larmor precession in the magnetic field; a microwave module is used to apply microwaves to the gas ions captured by the magnetic field; a power detection module is used to detect the microwave absorption power when the microwaves interact with the gas ions; a data analysis module is used to determine the gas components and the concentration of the gas components contained in the gas to be measured based on the microwave absorption power; because the gas molecules are ionized by using an electric field, the gas ions are captured by using a magnetic field, and the gas components and the concentration of the gas components contained in the gas to be measured are determined by the method of applying microwaves and monitoring the microwave absorption power, the gas components and their concentrations in the gas to be measured can be monitored quickly and accurately; because the Larmor precession frequencies and microwave absorption powers of different gas components are different, the monitoring of multiple different gas components can be realized; thus, the gas leaked from the battery can be monitored comprehensively, quickly and accurately, especially for the gas release in the initial stage of battery thermal runaway, and the safety of battery use is improved. Description of the Drawings

[0043] The drawings here are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with the present invention and used together with the specification to explain the principles of the present invention.

[0044] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0045] Figure 1 It is one of the structural schematic diagrams of the battery leakage gas monitoring device provided by the present invention.

[0046] Figure 2 It is the second structural schematic diagram of the battery leakage gas monitoring device provided by the present invention.

[0047] Figure 3 It is a schematic diagram of the Larmor precession frequencies of different characteristic gases provided by the present invention.

[0048] Figure 4 It is a schematic structural diagram of the gas ionization module provided by the present invention.

[0049] Figure 5 It is a schematic structural diagram of the magnetic confinement module provided by the present invention.

[0050] Figure 6 It is a schematic diagram of the gas concentration calibration provided by the present invention.

[0051] Figure 7 It is a schematic flow diagram of the method for monitoring battery leakage gas provided by the present invention.

[0052] Figure 8 It is a spectral diagram of the microwave absorption power of hydrogen ions provided by the present invention.

[0053] Figure 9 It is a spectral diagram of the microwave absorption power of multi-characteristic gases provided by the present invention.

[0054] Figure 10 It is a schematic structural diagram of the electronic device provided by the present invention. Detailed implementation manners

[0055] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0056] It should be noted that the terms "first", "second", etc. in the present invention are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units or modules does not necessarily need to be limited to those clearly listed steps or units or modules, but may include other steps or units or modules that are not clearly listed or are inherent to these processes, methods, products or devices.

[0057] With the continuous increase in the size and capacity of energy storage or power lithium batteries, the gases released during thermal runaway often increase exponentially. Therefore, it is necessary to conduct a detailed analysis of the types and quantities of gases released by large-capacity power lithium batteries during thermal runaway in order to take corresponding protective measures in the design and production of lithium battery packs. To ensure the safe use of lithium batteries, it is necessary to monitor the gases inside and around the lithium batteries in real time to detect and handle potential safety hazards in a timely manner.

[0058] On the other hand, by monitoring the gas leakage of lithium batteries, the health status of the batteries can also be evaluated, providing an important reference for battery maintenance and management. For example, when an abnormal increase in gas leakage is detected, it may indicate damage or aging inside the battery, and it is necessary to replace or repair it in a timely manner. Therefore, the monitoring of gas leakage in lithium batteries is a key link to ensure the safe operation of energy storage power stations based on lithium batteries.

[0059] During the process of lithium battery thermal runaway, various gases are mainly released, including carbon dioxide (CO2), carbon monoxide (CO), hydrogen (H2), and electrolyte volatiles. The changes in the composition and concentration of these gases can effectively reflect the chemical state inside the battery. In existing monitoring systems, gas monitoring devices are generally used to monitor the gas composition during thermal runaway. However, there are the following deficiencies: (1) The existing gas monitoring devices can monitor few types of gases. Generally, they can only monitor a specific type of gas, or the types of gases that can be monitored need to be increased by adding modules; (2) The sensitivity of the existing gas monitoring devices is relatively low, generally at the ppm level (one in a million), and at the initial stage of thermal runaway, the concentration of characteristic gases is extremely low, making it difficult to give an effective warning; (3) The response time is slow, generally taking 30 seconds or even longer, and it is impossible to give an effective warning.

[0060] To solve the deficiencies of the existing technology, Figure 1 is one of the structural schematic diagrams of the battery leakage gas monitoring device provided by the present invention. As Figure 1 shown, the battery leakage gas monitoring device 100 includes a gas collection module 110, a gas ionization module 120, a magnetic confinement module 130, a microwave module 140, a power detection module 150, and a data analysis module 160.

[0061] The gas collection module is used to sample the gases in the space around the battery to obtain the gas to be measured.

[0062] The gas ionization module is used to ionize the gas molecules in the gas to be measured to obtain gas ions.

[0063] The magnetic confinement module is used to capture the gas ions using a magnetic field; the gas ions perform Larmor precession in the magnetic field.

[0064] The microwave module is used to apply microwaves to the gas ions trapped by the magnetic field.

[0065] The power detection module is used to detect the microwave absorption power when microwaves interact with gas ions.

[0066] The data analysis module is used to determine the gas components and the concentrations of the gas components contained in the gas to be tested based on the microwave absorption power.

[0067] Specifically, the battery leakage gas monitoring device provided by the embodiment of the present invention is suitable for monitoring various electrochemical batteries, including energy storage batteries in energy storage power stations, power batteries in new energy vehicles, lithium batteries in consumer electronic products, etc. It is particularly suitable for effectively giving early warnings in the early stages of thermal runaway of various batteries when the concentration of characteristic gases is extremely low.

[0068] From the perspective of functional structure, the battery leakage gas monitoring device includes at least a gas collection module, a gas ionization module, a magnetic confinement module, a microwave module, a power detection module and a data analysis module.

[0069] The gas collection module is mainly used to be placed near the battery to sample the gas in the space around the battery to obtain the gas to be tested. The gas to be tested refers to the collected gas sample. The gas collection module can be placed in the battery cabinet. The battery cabinet is provided with multiple battery packs. The gas collection module collects the gas to be tested from the battery cabinet by suction.

[0070] The gas ionization module is used to ionize the gas to be tested collected by the gas collection module. Through the high-voltage electric field, the gas molecules in the gas to be tested lose or gain electrons, thereby becoming charged gas ions.

[0071] The magnetic confinement module is used to construct a magnetic field. The magnetic field can provide a stable environment in which ions are confined and controlled. Specifically, when gas ions are in a magnetic field, their magnetic moments will be affected by the external magnetic field and precess, and they will move at a certain frequency in the magnetic field (Larmor precession). This frequency is called the Larmor precession frequency. After the magnetic field strength is fixed, this frequency is only related to the charge and mass of the ions and has nothing to do with other quantities. The trajectory of the precession is a conical surface, in which the endpoints of the magnetic moment describe a circle on the bottom of the cone, and the axis of the cone coincides with the direction of the magnetic field.

[0072] The microwave module is used to apply microwaves to gas ions trapped by a magnetic field. Microwaves are a type of electromagnetic wave that can interact with gas ions, especially when the energy levels of the gas ions undergo transitions. The matching of the energy state of the ions and the microwave frequency affects the energy transfer. When the microwave frequency matches the Larmor precession frequency of the gas ions, the cyclotron motion of the gas ions in the magnetic field will exchange energy with the electric field of the microwave field, causing the ions to gain energy, usually manifested as the absorption of microwaves. At resonance, the efficiency of the ions absorbing microwave energy is very high, which enables the characteristics of the ions to be measured through the intensity of microwave absorption. The microwave absorption power refers to the intensity of the microwave energy absorbed by the gas ions when the microwaves interact with the gas ions. This intensity is related to factors such as the concentration, type, energy level structure of the gas ions, and the frequency and intensity of the microwaves. By measuring the microwave absorption power, the types, concentrations, and other physical characteristics of the gas ions can be understood.

[0073] The power detection module is used to detect the microwave absorption power when the microwaves interact with the gas ions.

[0074] The data analysis module is used to determine the gas components and the concentrations of the gas components contained in the gas to be measured based on the microwave absorption power. Gas components mainly refer to the characteristic gases contained in the gas to be measured. Characteristic gases are gases that have unique properties in a specific environment or specific application, and these properties enable them to be used as identifiers or signals in analysis, detection, or experiments, and can be determined as needed. For example, when a battery undergoes thermal runaway, the characteristic gases released may include carbon monoxide, carbon dioxide, and hydrogen, etc. The concentration of the gas component refers to the proportion of the characteristic gas in the gas mixture (the gas to be measured), usually expressed as the ratio of the mass, volume, or mole number of this gas to the total mass, volume, or mole number of the entire gas mixture.

[0075] The gas leakage gas monitoring device provided by the embodiment of the present invention, the gas collection module is used to sample the gas in the space around the battery to obtain the gas to be measured; the gas ionization module is used to ionize the gas molecules in the gas to be measured to obtain gas ions; the magnetic confinement module is used to capture the gas ions by using a magnetic field; the gas ions perform Larmor precession in the magnetic field; the microwave module is used to apply microwaves to the gas ions captured by the magnetic field; the power detection module is used to detect the microwave absorption power when the microwaves interact with the gas ions; the data analysis module is used to determine the gas components and the concentrations of the gas components contained in the gas to be measured based on the microwave absorption power; since the gas molecules are ionized by using an electric field, the gas ions are captured by using a magnetic field, and the gas components and the concentrations of the gas components contained in the gas to be measured are determined by applying microwaves and monitoring the microwave absorption power, the gas components and their concentrations in the gas to be measured can be monitored quickly and accurately; since the Larmor precession frequencies and microwave absorption powers of different gas components are different, the monitoring of multiple different gas components can be realized; thus, the gas leaked from the battery can be monitored comprehensively, quickly and accurately, especially for the gas release in the initial stage of battery thermal runaway, and the safety of battery use is improved.

[0076] In some embodiments, the device further includes a gas transmission pipeline and a vacuum module;

[0077] The first end of the gas transmission pipeline is connected to the gas collection module, and the second end is connected to the vacuum module; the gas transmission pipeline sequentially passes through the magnetic confinement module and the microwave module along the direction from the first end to the second end;

[0078] The vacuum module is used to generate negative pressure at the second end so that the gas to be measured flows out of the gas collection module and enters the vacuum module.

[0079] Specifically, Figure 2 is the second structural schematic diagram of the battery leakage gas monitoring device provided by the present invention, as Figure 2 shown, the device further includes a gas transmission pipeline 170 and a vacuum module 180.

[0080] The first end of the gas transmission pipeline is the intake end and is connected to the gas collection module; the second end is the outlet end and is connected to the vacuum module. The vacuum module is used to generate a certain negative pressure at the second end. Since the pressure at the second end is less than the pressure at the first end, the gas to be measured flows out of the gas collection module and enters the vacuum module through the gas transmission pipeline. The vacuum module can discharge the gas to be measured from the device.

[0081] The gas transmission pipeline sequentially passes through the magnetic confinement module and the microwave module along the direction from the first end to the second end, so that the magnetic confinement module can ionize the gas molecules in the gas transmission pipeline, and the microwave module can apply microwaves to the ionized gas ions.

[0082] The general process of battery leakage gas monitoring in the embodiments of the present invention is as follows:

[0083] When a lithium battery undergoes thermal runaway, it releases various gases, including characteristic gases such as carbon dioxide, carbon monoxide, hydrogen, and other electrolyte volatiles. The gas collection module placed around the lithium battery pack collects these gases and enters the gas transmission pipeline. In the gas ionization module, a strong electric field is generated between a high-voltage electrode of 1 kV (kilovolt) and the ground electrode to ionize the collected gas molecules and make them enter the ionic state. Subsequently, the gas ions enter the magnetic confinement module, which has a pair of Helmholtz coils that generate a magnetic confinement well to confine the ions. By controlling the current in the Helmholtz coils, different magnetic fields can be achieved. In this magnetic field, the ions perform helical motion, i.e., Larmor precession. Ions with different charge-to-mass ratios have inconsistent Larmor precession frequencies. Figure 3 It is a schematic diagram of the Larmor precession frequencies of different characteristic gases provided by the present invention. As Figure 3 shown, in different magnetic fields (such as 5 Gs, 10 Gs, and 20 Gs, where Gs is the unit of magnetic induction strength: gauss), the Larmor precession frequencies of ions of characteristic gases with different charge-to-mass ratios are different. Through the microwave module, a certain microwave power is applied to the gas ions confined in the magnetic confinement module; when the frequency of the microwave is changed, the microwave power absorbed by the ions at different frequencies is different, and the microwave power absorption value is detected by the power detection module. When the frequency of the microwave is consistent with the Larmor precession frequency of the ions, the microwave power absorption reaches the maximum at this time. Through the data analysis module, the Larmor precession frequency corresponding to the peak (maximum value) of the microwave power can be calculated, and then correlated with the ion type, and thus the ion type can be detected. At the same time, the absolute value of the absorbed microwave power is proportional to the number of ions, that is, the calibration of the ion number can be realized through the change amount of the absorbed microwave power, and the calibration of the gas concentration can be realized.

[0084] The battery leakage gas monitoring device provided by the embodiments of the present invention can make the gas to be measured flow through the magnetic confinement module and the microwave module in sequence by setting the gas transmission pipeline, which is convenient for applying the magnetic field and microwave; by setting the vacuum module, the flow rate of the gas to be measured can be accelerated, the monitoring speed of the leakage gas in the battery can be improved, and the gas release in the initial stage of battery thermal runaway can be quickly responded to.

[0085] In some embodiments, the gas ionization module includes a first electrode and a second electrode;

[0086] The first electrode and the second electrode are arranged in parallel along the flowing direction of the gas to be measured in the gas transmission pipeline;

[0087] An electric field is generated between the first electrode and the second electrode; the electric field is used to ionize gas molecules into gas ions.

[0088] Specifically, Figure 4 is a schematic structural diagram of the gas ionization module provided by the present invention, as Figure 4 shown, the gas ionization module 120 includes a first electrode 121 and a second electrode 122. The first electrode 121 and the second electrode 122 are arranged in parallel along the flowing direction of the gas to be measured in the gas transmission pipeline 170.

[0089] The first electrode can be a high-voltage electrode, and the second electrode can be a grounded electrode. The voltage between the first electrode and the second electrode can be 1 kV. Thus, an electric field is formed, and the electric field can ionize the incoming gas molecules into gas ions.

[0090] The battery leakage gas monitoring device provided by the embodiment of the present invention ionizes gas molecules into gas ions through the gas ionization module, which facilitates subsequent capture of gas ions and microwave power detection.

[0091] In some embodiments, the magnetic confinement module includes a first Helmholtz coil and a second Helmholtz coil;

[0092] The first Helmholtz coil and the second Helmholtz coil are arranged perpendicular to the flowing direction of the gas to be measured in the gas transmission pipeline;

[0093] A magnetic field is generated between the first Helmholtz coil and the second Helmholtz coil; the magnetic field is used to capture gas ions.

[0094] Specifically, Figure 5 is a schematic structural diagram of the magnetic confinement module provided by the present invention, as Figure 5 shown, the magnetic confinement module 130 includes a first Helmholtz coil 131 and a second Helmholtz coil 132. The first Helmholtz coil 131 and the second Helmholtz coil 132 are arranged perpendicular to the flowing direction of the gas to be measured in the gas transmission pipeline 170.

[0095] A stable and adjustable magnetic field can be formed between the first Helmholtz coil and the second Helmholtz coil to capture or confine gas ions.

[0096] The battery leakage gas monitoring device provided by the embodiment of the present invention captures gas ions by using the magnetic field through the magnetic confinement module, which facilitates subsequent application of microwaves to the gas ions and determination of gas components and concentrations by using microwave power detection.

[0097] In some embodiments, the data analysis module is used for:

[0098] Determining a spectral diagram of the microwave absorption power; the spectral diagram is used to record the correspondence between the microwave absorption power and the microwave frequency;

[0099] Determining at least one maximum value of the microwave absorption power in the spectral diagram;

[0100] Compare the microwave frequency corresponding to the maximum value of the microwave absorption power with the Larmor precession frequencies of the gas ions corresponding to each characteristic gas component;

[0101] When the microwave frequency is consistent with the Larmor precession frequency of the gas ions corresponding to any characteristic gas component, it is determined that the gas to be measured contains any characteristic gas component.

[0102] Specifically, the principle of detecting gas ions using microwaves is as follows: Detect the microwave power. When switching the microwave frequency, when the microwave frequency is consistent with the Larmor precession frequency of the gas ions in the magnetic field, the gas ions and the microwaves undergo cyclotron resonance, and the microwave absorption power reaches the maximum. At this time, the microwave absorption power detected by the power detection module will show a maximum value, and the frequency corresponding to this maximum value characterizes the ion type, that is, the corresponding gas component.

[0103] The detected microwave absorption power can be recorded in the form of a spectral line graph. The spectral line graph is used to record the correspondence between the microwave absorption power and the microwave frequency, and can reflect the relationship between the microwave absorption power and the change of the microwave frequency.

[0104] The spectral line graph can be traversed in ascending order of the microwave frequency to obtain one or more maximum values of the microwave absorption power in the spectral line graph.

[0105] Take any maximum value of the microwave absorption power as an example. Compare the microwave frequency corresponding to this maximum value of the microwave absorption power with the Larmor precession frequencies of the gas ions corresponding to each characteristic gas component. The characteristic gas components can be determined according to the characteristic gases generated by the thermal runaway of the battery, such as carbon monoxide, carbon dioxide, hydrogen, etc. The Larmor precession frequencies of the gas ions corresponding to the characteristic gas components can be determined in advance according to relevant experimental data, etc.

[0106] When the microwave frequency is consistent with the Larmor precession frequency of the gas ions corresponding to any characteristic gas component, it is determined that at least some of the gas ions are the gas ions corresponding to this characteristic gas component, that is, the gas to be measured contains this characteristic gas component.

[0107] In the above manner, each characteristic gas component contained in the gas to be measured can be determined one by one.

[0108] For the battery leakage gas monitoring device provided in the embodiment of the present invention, the resonance between the Larmor precession frequency of the released gas ions in the magnetic field and the microwave frequency, based on the resonance frequency corresponding to the maximum value of the microwave power absorption, realizes the discrimination of gas types and high-sensitivity monitoring, greatly improves the sensitivity of gas detection, and at the same time can achieve various types of monitoring, and the response time can also be improved to the second level.

[0109] In some embodiments, the data analysis module is configured to:

[0110] Based on the maximum value of the microwave absorption power and the corresponding relationship between the microwave absorption power of any characteristic gas component and the gas concentration, determine the gas concentration of any characteristic gas component in the gas to be measured.

[0111] Specifically, the corresponding relationship between the microwave absorption power of any characteristic gas component and the gas concentration can be calibrated in advance through relevant experimental data.

[0112] When it is determined that the gas to be measured contains any characteristic gas component according to the maximum value of the microwave absorption power, the gas concentration of this characteristic gas component in the gas to be measured can be further determined according to the corresponding relationship between the microwave absorption power of this characteristic gas component and the gas concentration.

[0113] Figure 6 is a schematic diagram of gas concentration calibration provided by the present invention. As Figure 6 shown, this figure shows the corresponding relationship between the relative value of the microwave absorption power of any characteristic gas component and the gas concentration, and this corresponding relationship can be fitted into a mathematical formula: . Wherein is the relative value of the microwave absorption power, is the gas concentration.

[0114] The battery leakage gas monitoring device provided by the embodiments of the present invention determines the gas concentration of any characteristic gas component in the gas to be measured according to the maximum value of the microwave absorption power and the corresponding relationship between the microwave absorption power of any characteristic gas component and the gas concentration, and realizes accurate monitoring of the leaked gas in the battery.

[0115] In some embodiments, the microwave module is configured to:

[0116] Determine the Larmor precession frequencies of the gas ions corresponding to multiple characteristic gas components;

[0117] Based on the minimum value and the maximum value among the Larmor precession frequencies of the gas ions corresponding to multiple characteristic gas components, determine the microwave frequency scanning range;

[0118] Based on the microwave frequency scanning range and the microwave frequency scanning step, apply microwaves with different microwave frequencies to the gas ions trapped by the magnetic field.

[0119] Specifically, in order to facilitate the detection of multiple different types of characteristic gases, the Larmor precession frequencies of the gas ions corresponding to multiple characteristic gas components can be determined in advance. According to the minimum value and the maximum value among these Larmor precession frequencies, the microwave frequency scanning range is determined.

[0120] The microwave frequency scanning step size can be set, and within the microwave frequency scanning range, microwaves of different microwave frequencies are applied to the gas ions trapped by the magnetic field. For example, the Larmor precession frequency of the gas ions corresponding to hydrogen (H2 + ), is 10.568 kHz (kilohertz), the Larmor precession frequency of the gas ions corresponding to carbon dioxide (CO2 + ), is 480 Hz (hertz), and the Larmor precession frequency of the gas ions corresponding to carbon monoxide (CO + ), is 754.8 Hz (hertz). Accordingly, the microwave frequency scanning range can be set to 100 Hz to 12 kHz, with a 50 Hz microwave frequency scanning step size, and the microwave absorption power at different frequency points is monitored.

[0121] The battery leakage gas monitoring device provided by the embodiments of the present invention can reasonably determine the microwave frequency scanning range according to the Larmor precession frequencies of the gas ions corresponding to multiple characteristic gas components, can more efficiently monitor the characteristic gases, improve the monitoring speed of the leakage gases in the battery, and facilitate a rapid response to the gas release in the initial stage of battery thermal runaway.

[0122] The method provided by the embodiments of the present invention will be described below, and the method described below can be mutually corresponding and referred to the device described above.

[0123] Figure 7 is a schematic flowchart of the battery leakage gas monitoring method provided by the present invention. As Figure 7 shown, this method is applied to the battery leakage gas monitoring device in the above embodiments, and includes step 710, step 720, step 730, step 740, step 750, and step 760.

[0124] Step 710: Based on the microwave frequency scanning range and the microwave frequency scanning step size, control the microwave module to apply microwaves of different microwave frequencies to the gas ions trapped by the magnetic field in the magnetic confinement module; the microwave frequency scanning range is determined based on the Larmor precession frequencies of the gas ions corresponding to multiple characteristic gas components.

[0125] Step 720: Obtain a spectral diagram of the microwave absorption power when the microwave interacts with the gas ions sent by the power detection module; the spectral diagram is used to record the corresponding relationship between the microwave absorption power and the microwave frequency.

[0126] Step 730: Determine at least one maximum value of the microwave absorption power in the spectral diagram.

[0127] Step 740: Compare the microwave frequency corresponding to the maximum value of the microwave absorption power with the Larmor precession frequencies of the gas ions corresponding to each characteristic gas component.

[0128] Step 750: When the microwave frequency is consistent with the Larmor precession frequency of the gas ions corresponding to any characteristic gas component, it is determined that the gas to be measured contains any characteristic gas component.

[0129] Step 760: Based on the maximum value of the microwave absorption power and the corresponding relationship between the microwave absorption power of any characteristic gas component and the gas concentration, the gas concentration of any characteristic gas component in the gas to be measured is determined.

[0130] Specifically, the battery leakage gas monitoring method provided by the present invention will be described below by taking hydrogen detection and multi-characteristic gas detection as examples respectively.

[0131] During the hydrogen detection process:

[0132] After the lithium battery thermal runaway, weak hydrogen is released. The gas collection module collects hydrogen and enters the gas transmission pipeline. The vacuum module uses a mechanical pump to generate a negative pressure of the order of Pa (Pascal), driving hydrogen into all subsequent modules. In the gas ionization module, hydrogen molecules are ionized into hydrogen ions by high voltage, generally in the form of H2 + form, the mass of the hydrogen ion is 3.372×10 -27 kg (kilogram), and the charge quantity is 1.67×10 -19 C (Coulomb). In the magnetic confinement module, the magnetic field strength is set to 10 Gs. At this time, the Larmor precession frequency of the hydrogen ions in the magnetic field is 10.568 kHz. Figure 8 is the spectral diagram of the microwave absorption power of the hydrogen ions provided by the present invention. As Figure 8 shown, the microwave power absorption spectrum of hydrogen ions under the condition of a 10 Gs magnetic field. The microwave frequency output by the microwave module is fixed at 10.568 kHz. The microwave absorption power measured by the power monitoring module. When the microwave power reaches the peak (maximum value), it indicates that hydrogen ions are captured by the magnetic confinement module, indicating that the lithium battery has released hydrogen. Before operation, the microwave absorption power of the system can be calibrated with standard gas components, and then the high-sensitivity detection of hydrogen components can be realized through the relative change value of the microwave absorption power at the fixed frequency of 10.568 kHz.

[0133] During the multi-characteristic gas detection process:

[0134] After the lithium battery thermal runaway, multiple gases such as carbon dioxide, carbon monoxide, and hydrogen will be released. The gas collection module collects these three gases and enters the gas transmission pipeline. The vacuum module uses a mechanical pump to generate a negative pressure of the order of Pa, driving the three gases into all subsequent modules. In the gas ionization module, hydrogen molecules are ionized into hydrogen ions by high voltage, generally in the form of H2 + form, the ion mass is 3.372×10 -27 kg, and the charge quantity is 1.67×10-19 C; The carbon dioxide molecule is ionized into CO2 + form, with an ion mass of 74.184×10 -27 kg and a charge quantity of 1.67×10 -19 C; The carbon monoxide molecule is ionized into CO + form, with an ion mass of 47.208×10 -27 kg and a charge quantity of 1.67×10 -19 C; In the magnetic confinement module, the magnetic field strength is set to 10 Gs. When the gas molecules released by the lithium battery pass through, the microwave absorption power curve measured by the power monitoring module will be at the background noise level, and because of the vacuum, the noise level is very low. Figure 9 is the spectral diagram of the microwave absorption power of the multi-characteristic gas provided by the present invention. As Figure 9 shown, peaks of microwave frequency absorption will appear at 6 frequency points such as 248 Hz, 264 Hz, 341 Hz, 360 Hz, 430 Hz, and 460 Hz, and there are ions corresponding to these 6 characteristic gases (components). Assuming that the switching time of one frequency point is 1 ms (millisecond) and the microwave detection time is 5 ms, the total time T during this multi-component detection process is: T = (12000 - 100) / 50 × (1 + 5) ms = 1.428 s. That is, within 1.428 seconds, the detection of 6 gas components is completed, and the detection efficiency is greatly improved.

[0135] The battery leakage gas monitoring method provided by the embodiments of the present invention can quickly and highly sensitively monitor the type and concentration of the battery leakage gas. Through the resonance of the Larmor precession frequency of the ions released by the gas in the magnetic field and the microwave frequency, the gas types are distinguished and highly sensitive monitoring is achieved based on the resonance frequency corresponding to the maximum value of the microwave power absorption, greatly improving the sensitivity of gas detection. At the same time, the monitoring of multiple characteristic gases can be realized, and the response time can also be improved to the second level.

[0136] Figure 10 is the structural schematic diagram of the electronic device provided by the present invention. As Figure 10 shown, the electronic device may include: a processor (Processor) 1010, a communication interface (Communications Interface) 1020, a memory (Memory) 1030, and a communication bus (Communications Bus) 1040. Among them, the processor 1010, the communication interface 1020, and the memory 1030 complete mutual communication through the communication bus 1040. The processor 1010 can call the logical commands in the memory 1030 to execute the method described in the above embodiments, for example:

[0137] Based on the microwave frequency scanning range and the microwave frequency scanning step size, control the microwave module to apply microwaves with different microwave frequencies to the gas ions trapped by the magnetic field in the magnetically confined module; the microwave frequency scanning range is determined based on the Larmor precession frequencies of the gas ions corresponding to multiple characteristic gas components; obtain the spectrogram of the microwave absorption power when the microwave interacts with the gas ions sent by the power detection module; the spectrogram is used to record the correspondence between the microwave absorption power and the microwave frequency; determine at least one maximum value of the microwave absorption power in the spectrogram; compare the microwave frequency corresponding to the maximum value of the microwave absorption power with the Larmor precession frequencies of the gas ions corresponding to each characteristic gas component; when the microwave frequency is consistent with the Larmor precession frequency of the gas ions corresponding to any characteristic gas component, determine that the gas to be measured contains any characteristic gas component; based on the maximum value of the microwave absorption power and the correspondence between the microwave absorption power of any characteristic gas component and the gas concentration, determine the gas concentration of any characteristic gas component in the gas to be measured.

[0138] In addition, when the logical commands in the above-mentioned memory can be implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several commands for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs, etc., all kinds of media that can store program codes.

[0139] The processor in the electronic device provided by the embodiments of the present invention can call the logical instructions in the memory to implement the above method. Its specific implementation manner is the same as that of the foregoing method embodiment and can achieve the same beneficial effects, which will not be elaborated here.

[0140] The embodiments of the present invention also provide a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it is used to execute the methods provided in the above various embodiments.

[0141] Its specific implementation manner is the same as that of the foregoing method embodiment and can achieve the same beneficial effects, which will not be elaborated here.

[0142] An embodiment of the present invention provides a computer program product, including a computer program which, when executed by a processor, implements the method as described above.

[0143] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. A person of ordinary skill in the art can understand and implement it without creative efforts.

[0144] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the essence of the above technical solution, or the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0145] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of each embodiment of the present invention.

Claims

1. A battery leakage gas monitoring device, characterized in that Including: A gas collection module for sampling the gas in the space around the battery to obtain the gas to be measured; A gas ionization module for ionizing the gas molecules in the gas to be measured to obtain gas ions; A magnetic confinement module for capturing the gas ions by using a magnetic field; the gas ions perform Larmor precession in the magnetic field; A microwave module for applying microwaves to the gas ions captured by the magnetic field; A power detection module for detecting the microwave absorption power when the microwaves interact with the gas ions; A data analysis module for determining the gas components contained in the gas to be measured and the concentration of the gas components based on the microwave absorption power; The data analysis module is used for: Determining a spectrogram of the microwave absorption power; the spectrogram is used to record the correspondence between the microwave absorption power and the microwave frequency; Determining at least one maximum value of the microwave absorption power in the spectrogram; Comparing the microwave frequency corresponding to the maximum value of the microwave absorption power with the Larmor precession frequencies of the gas ions corresponding to each characteristic gas component; When the microwave frequency is consistent with the Larmor precession frequency of the gas ions corresponding to any characteristic gas component, determining that the gas to be measured contains the any characteristic gas component.

2. The battery leakage gas monitoring device according to claim 1, wherein The device further includes a gas transmission pipeline and a vacuum module; The first end of the gas transmission pipeline is connected to the gas collection module, and the second end is connected to the vacuum module; the gas transmission pipeline sequentially passes through the magnetic confinement module and the microwave module along the direction from the first end to the second end; The vacuum module is used for generating negative pressure at the second end so that the gas to be measured flows out of the gas collection module and enters the vacuum module.

3. The battery leakage gas monitoring device according to claim 2, characterized in that, The gas ionization module includes a first electrode and a second electrode; The first electrode and the second electrode are arranged in parallel along the flowing direction of the gas to be measured in the gas transmission pipeline; An electric field is generated between the first electrode and the second electrode; The electric field is used for ionizing the gas molecules into the gas ions.

4. The battery leakage gas monitoring device according to claim 2, characterized in that, The magnetic confinement module includes a first Helmholtz coil and a second Helmholtz coil; The first Helmholtz coil and the second Helmholtz coil are arranged perpendicular to the flowing direction of the gas to be measured in the gas transmission pipeline; A magnetic field is generated between the first Helmholtz coil and the second Helmholtz coil; the magnetic field is used for capturing the gas ions.

5. The battery leakage gas monitoring device according to claim 1, wherein The data analysis module is used for: Based on the maximum value of the microwave absorption power and the correspondence between the microwave absorption power of the any characteristic gas component and the gas concentration, determining the gas concentration of the any characteristic gas component in the gas to be measured.

6. The battery leakage gas monitoring device according to claim 1, wherein, The microwave module is used for: Determining the Larmor precession frequencies of the gas ions corresponding to multiple characteristic gas components; Based on the minimum value and the maximum value of the Larmor precession frequencies of the gas ions corresponding to the multiple characteristic gas components, determining the microwave frequency scanning range; Based on the microwave frequency scanning range and the microwave frequency scanning step, applying microwaves with different microwave frequencies to the gas ions captured by the magnetic field.

7. A method for monitoring battery leakage gas, characterized in that, Applied to the battery leakage gas monitoring device according to any one of claims 1 to 6, comprising: Based on the microwave frequency scanning range and the microwave frequency scanning step, controlling the microwave module to apply microwaves with different microwave frequencies to the gas ions captured by the magnetic field in the magnetic confinement module; the microwave frequency scanning range is determined based on the Larmor precession frequencies of the gas ions corresponding to multiple characteristic gas components; Obtaining a spectral diagram of the microwave absorption power when the microwave interacts with the gas ions sent by the power detection module; the spectral diagram is used to record the correspondence between the microwave absorption power and the microwave frequency; Determining at least one maximum value of the microwave absorption power in the spectral diagram; Comparing the microwave frequency corresponding to the maximum value of the microwave absorption power with the Larmor precession frequencies of the gas ions corresponding to each characteristic gas component; When the microwave frequency is consistent with the Larmor precession frequency of the gas ions corresponding to any one of the characteristic gas components, determining that the gas to be measured contains the any one of the characteristic gas components; Based on the maximum value of the microwave absorption power and the correspondence between the microwave absorption power of any one of the characteristic gas components and the gas concentration, determining the gas concentration of any one of the characteristic gas components in the gas to be measured.

8. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the battery leakage gas monitoring method according to claim 7.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the battery leakage gas monitoring method according to claim 7.

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