Battery leakage gas monitoring device and method

Abstract

The invention provides a battery leakage gas monitoring device and method, and relates to the technical field of battery safety management, and the device comprises a gas collection module which is used for sampling gas in the surrounding space of a battery to obtain to-be-detected gas; the gas ionization module is used for ionizing gas molecules in the to-be-detected gas to obtain gas ions; the magnetic confinement module is used 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; the power detection module is used for detecting microwave absorption power when the microwaves interact with the gas ions; and the data analysis module is used for determining gas components contained in the to-be-detected gas and the concentration of the gas components based on the microwave absorption power. According to the device and the method provided by the invention, the gas leaked from the battery can be comprehensively, quickly and accurately monitored.

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 will be 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: A gas collection module is used to sample the gas in the space around the battery to obtain the gas to be tested; A gas ionization module, used for ionizing gas molecules in the gas to be measured to obtain gas ions; 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; a microwave module, for applying microwaves to the gas ions trapped by the magnetic field; A power detection module, used for detecting microwave absorption power when the microwave interacts with the gas ions; 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.

[0007] In some embodiments, the apparatus further comprises a gas delivery conduit 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 in a direction from the first end to the second end; The vacuum module is used to generate negative pressure at the second end so that the gas to be tested flows out of the gas collection module and enters the vacuum module.

[0008] In some embodiments, 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 flow 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 to ionize the gas molecules into the gas ions.

[0009] In some embodiments, 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 vertically along the flow 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 to capture the gas ions.

[0010] In some embodiments, the data analysis module is used to: Determine a spectrum diagram of the microwave absorption power; the spectrum diagram is used to record the corresponding relationship between the microwave absorption power and the microwave frequency; Determining at least one microwave absorption power maximum in the spectrum diagram; Comparing the microwave frequency corresponding to the microwave absorption power maximum with the Larmor precession frequency 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, it is determined that the gas to be measured contains the any characteristic gas component.

[0011] In some embodiments, the data analysis module is used to: Based on the maximum 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.

[0012] In some embodiments, the microwave module is used to: determining Larmor precession frequencies of gas ions corresponding to a plurality of characteristic gas components; Determining a microwave frequency scanning range based on a minimum value and a maximum value among Larmor precession frequencies of gas ions corresponding to the plurality of characteristic gas components; Based on the microwave frequency scanning range and the microwave frequency scanning step size, microwaves of different microwave frequencies are applied to the gas ions trapped in the magnetic field.

[0013] The present invention provides a battery leakage gas monitoring method, which is applied to the battery leakage gas monitoring device, comprising: Based on a microwave frequency scanning range and a microwave frequency scanning step, controlling 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 the plurality of characteristic gas components; Acquire a spectrum diagram of microwave absorption power when the microwave sent by the power detection module interacts with the gas ions; the spectrum diagram is used to record the corresponding relationship between the microwave absorption power and the microwave frequency; Determining at least one microwave absorption power maximum in the spectrum diagram; Comparing the microwave frequency corresponding to the microwave absorption power maximum with the Larmor precession frequency 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; Based on the maximum 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.

[0014] The present invention provides an electronic device, comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the battery leakage gas monitoring method is implemented when the processor executes the computer program.

[0015] 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 is implemented.

[0016] The battery leakage gas monitoring device and method provided by the present invention include a gas collection module for sampling gas in the space around the battery to obtain a gas to be tested; a gas ionization module for ionizing gas molecules in the gas to be tested to obtain gas ions; a magnetic confinement module for capturing gas ions by using a magnetic field; gas ions undergo Larmor precession in the magnetic field; a microwave module for applying microwaves to gas ions captured by the magnetic field; a power detection module for detecting microwave absorption power when microwaves interact with gas ions; a data analysis module for determining gas components and concentrations of gas components contained in the gas to be tested based on microwave absorption power; since gas molecules are ionized by an electric field and gas ions are captured by a magnetic field, the gas components and concentrations of gas components contained in the gas to be tested are determined by applying microwaves and monitoring microwave absorption power, so that the gas components and concentrations in the gas to be tested can be monitored quickly and accurately; since the Larmor precession frequencies and microwave absorption powers of different gas components are different, monitoring of multiple different gas components can be achieved; thereby achieving comprehensive, rapid and accurate monitoring of gas leakage in the battery, especially rapid response to gas release in the early stage of thermal runaway of the battery, and improving the safety of battery use. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is one of the structural schematic diagrams of the battery leakage gas monitoring device provided by the present invention.

[0020] Figure 2 This is the second structural schematic diagram of the battery leakage gas monitoring device provided by the present invention.

[0021] Figure 3 It is a schematic diagram of the Larmor precession frequency of different characteristic gases provided by the present invention.

[0022] Figure 4 It is a structural schematic diagram of the gas ionization module provided by the present invention.

[0023] Figure 5 It is a structural schematic diagram of the magnetic confinement module provided by the present invention.

[0024] Figure 6 It is a schematic diagram of gas concentration calibration provided by the present invention.

[0025] Figure 7 It is a flow chart of the battery leakage gas monitoring method provided by the present invention.

[0026] Figure 8 It is a spectrum diagram of the microwave absorption power of hydrogen ions provided by the present invention.

[0027] Fig. 9 It is a spectrum diagram of microwave absorption power of multiple characteristic gases provided by the present invention.

[0028] Fig.10 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0030] It should be noted that the terms "first", "second", etc. in the present invention are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, 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 "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units or modules is not necessarily limited to those steps or units or modules that are clearly listed, but may include other steps or units or modules that are not clearly listed or inherent to these processes, methods, products or devices.

[0031] As the size and capacity of energy storage or power lithium batteries continue to increase, the gases released by 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, so as 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 so as to promptly discover and deal with potential safety hazards.

[0032] On the other hand, by monitoring the gas leakage of lithium batteries, the health status of the battery 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 mean that there is damage or aging inside the battery, which needs to be replaced or repaired in time. Therefore, monitoring the gas leakage of lithium batteries is a key link in ensuring the safe operation of energy storage power stations based on lithium batteries.

[0033] During the thermal runaway of lithium batteries, a variety of gases are mainly released, including carbon dioxide (CO2), carbon monoxide (CO), hydrogen (H2) and electrolyte volatiles. The composition and concentration changes of these gases can effectively reflect the chemical state inside the battery. In the existing monitoring system, a gas monitoring device is generally used to monitor the gas composition during thermal runaway. However, there are the following shortcomings: (1) The existing gas monitoring device monitors a small number of gas types and can generally only monitor a specific type of gas, or it is necessary to increase the type of gas that can be monitored by adding modules; (2) The existing gas monitoring device has a low sensitivity, generally at the ppm level (parts per million), and in the early stage of thermal runaway, the concentration of characteristic gases is extremely low, making it difficult to effectively give an early warning; (3) The response time is slow, generally taking 30 seconds or even longer, and it is impossible to effectively give an early warning.

[0034] In order to solve the shortcomings 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, such as Figure 1 As 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 .

[0035] The gas collection module is used to sample the gas in the space around the battery to obtain the gas to be tested.

[0036] The gas ionization module is used to ionize the gas molecules in the gas to be tested to obtain gas ions.

[0037] The magnetic confinement module is used to capture gas ions using a magnetic field; the gas ions undergo Larmor precession in the magnetic field.

[0038] The microwave module is used to apply microwaves to the gas ions trapped by the magnetic field.

[0039] The power detection module is used to detect the microwave absorption power when microwaves interact with gas ions.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] The microwave module is used to apply microwaves to gas ions trapped in a magnetic field. Microwaves are a type of electromagnetic wave that can interact with gas ions, especially when the energy levels of gas ions transition. 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, which is usually manifested as microwave absorption. In resonance, the efficiency of ions absorbing microwave energy is very high, which makes it possible to measure the characteristics of the ions by the intensity of microwave absorption. Microwave absorption power refers to the intensity of microwave energy absorbed by gas ions when microwaves interact with gas ions. This intensity is related to factors such as the concentration, type, and energy level structure of the gas ions, as well as the frequency and intensity of the microwaves. By measuring the microwave absorption power, the type, concentration, and other physical characteristics of the gas ions can be understood.

[0047] The power detection module is used to detect the microwave absorption power when microwaves interact with gas ions.

[0048] The data analysis module is used to determine the gas components and concentrations of the gas components contained in the gas to be tested based on the microwave absorption power. The gas components mainly refer to the characteristic gases contained in the gas to be tested. Characteristic gases refer to gases with unique properties under specific environments or in specific applications. 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 thermally runs away, the characteristic gases released may include carbon monoxide, carbon dioxide, and hydrogen. The concentration of a gas component refers to the proportion of the characteristic gas in the gas mixture (gas to be tested), usually expressed as the ratio of the mass, volume or number of moles of the gas to the total mass, volume or number of moles of the entire gas mixture.

[0049] The battery leakage gas monitoring device provided by the embodiment of the present invention comprises a gas collection module for sampling the gas in the space around the battery to obtain the gas to be tested; a gas ionization module for ionizing the gas molecules in the gas to be tested to obtain the gas ions; a magnetic confinement module for capturing the gas ions by using the magnetic field; the gas ions undergo 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 and the concentrations of the gas components contained in the gas to be tested based on the microwave absorption power; since the gas molecules are ionized by the electric field and the gas ions are captured by the magnetic field, the gas components and the concentrations of the gas components contained in the gas to be tested are determined by applying microwaves and monitoring the microwave absorption power, so that the gas components and their concentrations in the gas to be tested 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; thereby, the gas leaked in the battery can be fully, quickly and accurately monitored, especially the gas release in the early stage of thermal runaway of the battery can be quickly responded to, thereby improving the safety of battery use.

[0050] In some embodiments, the apparatus further comprises a gas delivery conduit 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 in a direction from the first end to the second end; The vacuum module is used to generate negative pressure at the second end so that the gas to be tested flows out of the gas collection module and enters the vacuum module.

[0051] Specifically, Figure 2 This is a second structural diagram of the battery leakage gas monitoring device provided by the present invention, such as Figure 2 As shown, the device further includes a gas transmission pipeline 170 and a vacuum module 180 .

[0052] The first end of the gas transmission pipeline is the gas inlet end, which is connected to the gas collection module; the second end is the gas outlet end, which 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 tested 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 tested out of the device.

[0053] The gas transmission pipeline passes through the magnetic confinement module and the microwave module in sequence 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.

[0054] The general process of battery leakage gas monitoring in the embodiment of the present invention is: When a lithium battery thermally runs away, it will release a variety of 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 1kV (kilovolt) high-voltage electrode is set to generate a strong electric field between the ground electrode to ionize the collected gas molecules and put them into an ion state. The gas ions then enter the magnetic confinement module, which contains a pair of Helmholtz coils to generate a magnetic confinement trap to confine the ions. Different magnetic fields can be achieved by controlling the current in the Helmholtz coils. In this magnetic field, the ions perform spiral motion, which is Larmor precession. The frequencies of Larmor precession of ions with different charge-to-mass ratios are inconsistent. Figure 3 is a schematic diagram of Larmor precession frequency of different characteristic gases provided by the present invention, such as Figure 3 As shown, the Larmor precession frequency of ions of characteristic gases with different charge-to-mass ratios in different magnetic fields (e.g., 5Gs, 10Gs, and 20Gs, where Gs is the unit of magnetic induction intensity: Gauss) is different. A certain microwave power is applied to the gas ions confined in the magnetic confinement module through the microwave module; when the microwave frequency 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 microwave frequency is consistent with the frequency of ion Larmor precession, the microwave power absorption reaches the maximum. Through the data analysis module, the Larmor precession frequency corresponding to the peak value (maximum value) of the microwave power can be calculated, and then associated with the ion type, and then 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 number of ions can be calibrated by the change in the absorbed microwave power, and the gas concentration can be calibrated.

[0055] The battery leakage gas monitoring device provided in an embodiment of the present invention can allow the gas to be tested to flow through the magnetic confinement module and the microwave module in sequence by setting a gas transmission pipeline, thereby facilitating the application of a magnetic field and microwaves; a vacuum module is set to accelerate the flow rate of the gas to be tested, thereby improving the monitoring speed of the leaked gas in the battery and facilitating a rapid response to gas release in the early stage of thermal runaway of the battery.

[0056] In some embodiments, 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 flow 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 to ionize the gas molecules into gas ions.

[0057] Specifically, Figure 4 is a schematic diagram of the structure of the gas ionization module provided by the present invention, such as Figure 4 As 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 flow direction of the gas to be measured in the gas transmission pipeline 170.

[0058] The first electrode may be a high voltage electrode, and the second electrode may be a ground electrode. The voltage between the first electrode and the second electrode may be 1 kV, thereby forming an electric field, which can ionize the inflowing gas molecules into gas ions.

[0059] The battery leakage gas monitoring device provided in the embodiment of the present invention ionizes gas molecules into gas ions through a gas ionization module, thereby facilitating the subsequent capture of gas ions and microwave power detection.

[0060] In some embodiments, 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 vertically along the flow 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 to capture gas ions.

[0061] Specifically, Figure 5 is a schematic diagram of the structure of the magnetic confinement module provided by the present invention, such as Figure 5 As 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 vertically arranged along the flow direction of the gas to be measured in the gas transmission pipeline 170.

[0062] A stable and adjustable magnetic field can be formed between the first Helmholtz coil and the second Helmholtz coil to capture or trap gas ions.

[0063] The battery leakage gas monitoring device provided in the embodiment of the present invention uses a magnetic field to capture gas ions through a magnetic confinement module, so as to facilitate the subsequent application of microwaves to the gas ions and the use of microwave power detection to determine the gas composition and concentration.

[0064] In some embodiments, the data analysis module is used to: Determine the spectrum of microwave absorption power; the spectrum is used to record the corresponding relationship between microwave absorption power and microwave frequency; determining at least one microwave absorption power maximum in the spectrum; The microwave frequency corresponding to the maximum value of microwave absorption power is compared with the Larmor precession frequency of 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, it is determined that the gas to be measured contains any characteristic gas component.

[0065] Specifically, the principle of using microwaves to detect gas ions is: to detect 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 microwaves undergo cyclotron resonance, and the microwave absorption power reaches a maximum. At this time, the microwave absorption power detected by the power detection module will have a maximum value, and the frequency corresponding to the maximum value characterizes the ion type, that is, the corresponding gas component.

[0066] The detected microwave absorption power can be recorded in the form of a spectrum diagram. The spectrum diagram is used to record the corresponding relationship between microwave absorption power and microwave frequency, and can reflect the relationship between microwave absorption power and microwave frequency.

[0067] The spectrum diagram can be traversed in order of microwave frequency from small to large to obtain one or more microwave absorption power maxima in the spectrum diagram.

[0068] Take any microwave absorption power maximum as an example. Compare the microwave frequency corresponding to the microwave absorption power maximum with the Larmor precession frequency of the gas ions corresponding to each characteristic gas component. The characteristic gas component can be determined based on the characteristic gas generated by battery thermal runaway, for example, it may include carbon monoxide, carbon dioxide and hydrogen. The Larmor precession frequency of the gas ions corresponding to the characteristic gas component can be determined in advance based on relevant experimental data.

[0069] 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 gas ions corresponding to the characteristic gas component, that is, the gas to be measured contains the characteristic gas component.

[0070] According to the above method, each characteristic gas component contained in the gas to be measured can be determined one by one.

[0071] The battery leakage gas monitoring device provided in the embodiment of the present invention realizes the resonance of the Larmor precession frequency of the released gas ions in the magnetic field and the microwave frequency, and realizes the differentiation of gas types and high-sensitivity monitoring based on the resonance frequency corresponding to the maximum value of microwave power absorption, which greatly improves the sensitivity of gas detection, and can realize various types of monitoring at the same time, and the response time can also be improved to seconds.

[0072] In some embodiments, the data analysis module is used to: Based on the maximum value of 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.

[0073] 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.

[0074] When it is determined that the gas to be measured contains any characteristic gas component based on the maximum microwave absorption power, the gas concentration of the characteristic gas component in the gas to be measured can be further determined based on the corresponding relationship between the microwave absorption power of the characteristic gas component and the gas concentration.

[0075] Figure 6 Schematic diagram of gas concentration calibration provided by the present invention, such as Figure 6 As shown in the figure, the corresponding relationship between the relative value of microwave absorption power of any characteristic gas component and the gas concentration can be fitted into a mathematical relationship: .in is the relative value of microwave absorption power, is the gas concentration.

[0076] The battery leakage gas monitoring device provided in the embodiment of the present invention determines the gas concentration of any characteristic gas component in the gas to be tested based on the maximum value of microwave absorption power and the corresponding relationship between the microwave absorption power of any characteristic gas component and the gas concentration, thereby realizing accurate monitoring of gas leakage in the battery.

[0077] In some embodiments, the microwave module is used to: determining Larmor precession frequencies of gas ions corresponding to a plurality of characteristic gas components; Determining a microwave frequency scanning range based on minimum and maximum values ​​of Larmor precession frequencies of gas ions corresponding to a plurality of characteristic gas components; Microwaves of different microwave frequencies are applied to the gas ions trapped in the magnetic field based on the microwave frequency scanning range and the microwave frequency scanning step size.

[0078] Specifically, in order to facilitate the detection of multiple different types of characteristic gases, the Larmor precession frequencies of gas ions corresponding to multiple characteristic gas components can be predetermined, and the microwave frequency scanning range can be determined according to the minimum and maximum values ​​of these Larmor precession frequencies.

[0079] The microwave frequency scanning step can be set, and microwaves of different frequencies are applied to the gas ions captured by the magnetic field within the microwave frequency scanning range. For example, the gas ions corresponding to hydrogen (H2 + ) has a Larmor precession frequency of 10.568kHz (kilohertz), and the gas ions corresponding to carbon dioxide (CO2 + ) has a Larmor precession frequency of 480 Hz (Hertz), and the gas ions corresponding to carbon monoxide (CO + ) is 754.8 Hz (Hertz). Based on this, the microwave frequency scanning range can be set to 100 Hz to 12 kHz, with a microwave frequency scanning step of 50 Hz, to monitor the microwave absorption power at different frequency points.

[0080] The battery leakage gas monitoring device provided in the embodiment of the present invention can reasonably determine the microwave frequency scanning range according to the Larmor precession frequency of the gas ions corresponding to multiple characteristic gas components, so as to more efficiently monitor the characteristic gas, improve the monitoring speed of the leakage gas in the battery, and facilitate rapid response to the gas release in the early stage of thermal runaway of the battery.

[0081] The method provided by the embodiment of the present invention is described below. The method described below and the device described above can be referenced to each other.

[0082] Figure 7 : is a flow chart of the battery leakage gas monitoring method provided by the present invention, such as Figure 7 As shown, the method is applied to the battery leakage gas monitoring device in the above embodiment, including step 710, step 720, step 730, step 740, step 750 and step 760.

[0083] Step 710: Based on the microwave frequency scanning range and the microwave frequency scanning step, control the microwave module to apply microwaves of 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 frequency of the gas ions corresponding to multiple characteristic gas components.

[0084] Step 720: Obtain a spectrum diagram of microwave absorption power when microwaves sent by the power detection module interact with gas ions; the spectrum diagram is used to record the corresponding relationship between microwave absorption power and microwave frequency.

[0085] Step 730: Determine at least one microwave absorption power maximum in the spectrum diagram.

[0086] Step 740: compare the microwave frequency corresponding to the microwave absorption power maximum with the Larmor precession frequency of the gas ions corresponding to each characteristic gas component.

[0087] Step 750: 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.

[0088] Step 760: Based on the maximum value of 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.

[0089] Specifically, the battery leakage gas monitoring method provided by the present invention is described below by taking hydrogen detection and multiple characteristic gas detection as examples.

[0090] During hydrogen detection: When the lithium battery thermally runs away, it releases weak hydrogen. The gas collection module collects the hydrogen and enters the gas transmission pipeline. The vacuum module uses a mechanical pump to generate a negative pressure of Pa (Pascals) to drive the hydrogen into all subsequent modules. In the gas ionization module, hydrogen molecules are ionized into hydrogen ions by high pressure, generally H2 + The mass of hydrogen ion is 3.372×10 -27 kg (kilogram), the charge is 1.67×10 -19 C (Coulomb), in the magnetic confinement module, set the magnetic field strength to 10Gs. At this time, the Larmor precession frequency of hydrogen ions in the magnetic field is 10.568kHz. Figure 8 is a spectrum diagram of the microwave absorption power of hydrogen ions provided by the present invention, such as Figure 8 As shown in the figure, the hydrogen ion microwave power absorption spectrum under 10Gs magnetic field conditions. The microwave frequency output by the fixed microwave module is 10.568kHz. The microwave absorption power measured by the power monitoring module, when the microwave power reaches the peak value (maximum value), indicates that hydrogen ions are captured by the magnetic confinement module, indicating that the lithium battery has released hydrogen. Before work, the microwave absorption power of the system can be calibrated by the standard gas composition, and the high-sensitivity detection of the hydrogen component can be achieved by the relative change value of the microwave absorption power at a fixed frequency of 10.568kHz.

[0091] During multi-signature gas detection: When a lithium battery goes into thermal runaway, it will release a variety of gases such as carbon dioxide, carbon monoxide, and hydrogen. 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 Pa level to drive the three gases into all subsequent modules. In the gas ionization module, hydrogen molecules are ionized into hydrogen ions by high pressure, generally H2 + form, the ion mass is 3.372×10 -27 kg, and the charge is 1.67×10 -19 C; Carbon dioxide molecules are ionized into CO2 + form, the ion mass is 74.184×10 -27 kg, and the charge is 1.67×10 -19 C; Carbon monoxide molecules are ionized into CO + form, the ion mass is 47.208×10 -27 kg, and the charge is 1.67×10 -19 C; In the magnetic confinement module, set the magnetic field strength to 10Gs. When the gas molecules released by the lithium battery, the microwave absorption power curve measured by the power monitoring module will be the background noise level, and because of the vacuum, the noise level is very low. Fig. 9 is a spectrum of microwave absorption power of multiple characteristic gases provided by the present invention, such as Fig. 9 As shown in the figure, there are peaks of microwave frequency absorption at 6 frequency points, namely 248Hz, 264Hz, 341Hz, 360Hz, 430Hz and 460Hz, and there are ions corresponding to these 6 characteristic gases (components). Assuming that the switching time of a frequency point is 1ms (milliseconds) and the microwave detection time is 5ms, the total time consumed in this multi-component detection process is: T = (12000-100) / 50×(1+5)ms=1.428s. That is, within 1.428 seconds, the detection of 6 gas components is completed, and the detection efficiency is greatly improved.

[0092] The battery leakage gas monitoring method provided in the embodiment of the present invention can quickly and highly sensitively monitor the type and concentration of battery leakage gas. Through the resonance of the Larmor precession frequency of the ions releasing the gas in the magnetic field and the microwave frequency, the gas type distinction and high-sensitivity monitoring are realized based on the resonance frequency corresponding to the maximum value of microwave power absorption, which greatly improves the sensitivity of gas detection. At the same time, it can realize the monitoring of multiple characteristic gases, and the response time can also be improved to seconds.

[0093] Fig.10 is a schematic diagram of the structure of the electronic device provided by the present invention, such as Fig.10As 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, wherein the processor 1010, the communication interface 1020, and the memory 1030 communicate with each other through the communication bus 1040. The processor 1010 may call the logic command in the memory 1030 to execute the method described in the above embodiment, for example: Based on the microwave frequency scanning range and the microwave frequency scanning step, the microwave module is controlled to apply microwaves of 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 the multiple characteristic gas components; a spectrum diagram of the microwave absorption power when the microwaves sent by the power detection module interact with the gas ions is obtained; the spectrum diagram is used to record the corresponding relationship between the microwave absorption power and the microwave frequency; at least one microwave absorption power maximum value in the spectrum diagram is determined; the microwave frequency corresponding to the microwave absorption power maximum value is compared with the Larmor precession frequency 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, it is determined that the gas to be measured contains any characteristic gas component; based on the microwave absorption power maximum value, 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.

[0094] In addition, the logic commands in the above-mentioned memory can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several commands to enable a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program code.

[0095] The processor in the electronic device provided in the embodiment of the present invention can call the logic instructions in the memory to implement the above method. Its specific implementation method is consistent with the implementation method of the aforementioned method and can achieve the same beneficial effects, which will not be repeated here.

[0096] An embodiment of the present invention further 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 methods provided in the above embodiments are implemented.

[0097] Its specific implementation is consistent with the aforementioned method implementation and can achieve the same beneficial effects, so it will not be repeated here.

[0098] An embodiment of the present invention provides a computer program product, including a computer program. When the computer program is executed by a processor, the method described above is implemented.

[0099] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0100] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for 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.

[0101] 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 it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A battery leakage gas monitoring device, characterized in that: include: A gas collection module is used to sample the gas in the space around the battery to obtain the gas to be tested; A gas ionization module, used for ionizing gas molecules in the gas to be measured to obtain gas ions; 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; a microwave module, for applying microwaves to the gas ions trapped by the magnetic field; A power detection module, used for detecting microwave absorption power when the microwave interacts with the gas ions; 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.

2. The battery leakage gas monitoring device according to claim 1, characterized in that: The device also 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 in a direction from the first end to the second end; The vacuum module is used to generate negative pressure at the second end so that the gas to be tested 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 comprises a first electrode and a second electrode; The first electrode and the second electrode are arranged in parallel along the flow 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 to ionize 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 vertically along the flow 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 to capture the gas ions.

5. The battery leakage gas monitoring device according to claim 1, characterized in that: The data analysis module is used for: Determine a spectrum diagram of the microwave absorption power; the spectrum diagram is used to record the corresponding relationship between the microwave absorption power and the microwave frequency; Determining at least one microwave absorption power maximum in the spectrum diagram; Comparing the microwave frequency corresponding to the microwave absorption power maximum with the Larmor precession frequency 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, it is determined that the gas to be measured contains the any characteristic gas component.

6. The battery leakage gas monitoring device according to claim 5, characterized in that: The data analysis module is used for: Based on the maximum 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.

7. The battery leakage gas monitoring device according to claim 1, characterized in that: The microwave module is used for: determining Larmor precession frequencies of gas ions corresponding to a plurality of characteristic gas components; Determining a microwave frequency scanning range based on a minimum value and a maximum value among Larmor precession frequencies of gas ions corresponding to the plurality of characteristic gas components; Based on the microwave frequency scanning range and the microwave frequency scanning step size, microwaves of different microwave frequencies are applied to the gas ions trapped in the magnetic field.

8. A battery leakage gas monitoring method, characterized in that: The battery leakage gas monitoring device according to any one of claims 1 to 7 comprises: Based on a microwave frequency scanning range and a microwave frequency scanning step, controlling 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 the plurality of characteristic gas components; Acquire a spectrum diagram of microwave absorption power when the microwave sent by the power detection module interacts with the gas ions; the spectrum diagram is used to record the corresponding relationship between the microwave absorption power and the microwave frequency; Determining at least one microwave absorption power maximum in the spectrum diagram; Comparing the microwave frequency corresponding to the microwave absorption power maximum with the Larmor precession frequency 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; Based on the maximum 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.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the battery leakage gas monitoring method according to claim 8 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the battery leakage gas monitoring method according to claim 8 is implemented.

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