A thermal battery safety test system with gas collection and analysis function

Abstract

The application discloses a thermal battery safety test system with gas collection and analysis functions, comprising a measured thermal battery, a battery performance testing device, a safety test device, a gas separation and collection device, a gas analysis instrument and a central control analysis processing module; the measured thermal battery is of a sealed structure, and a gas interface is processed on the shell; the gas separation and collection device comprises a gas-liquid-solid three-phase product buffer separator, a pressure sensor, an electromagnetic valve, a vacuum pump, a gas collection container, an inert gas cylinder, a pressure relief device and a gas pipeline connected with each component, and is used for separating and leading out the gas generated by the thermal battery in the safety test; the central control analysis processing module uniformly and coordinately controls each device to promote the test process according to a predetermined time sequence, and carries out summary analysis on parameters such as gas components, gas pressure and temperature. Real-time collection and analysis of the internal gas of the thermal battery can be realized in the extreme safety test of the thermal battery short circuit, backfill charging, baking explosion, thermal abuse and insulation breakdown.

Description

Technical Field

[0001] This invention belongs to the field of thermal battery technology, specifically relating to a thermal battery safety testing system with gas collection and analysis functions. Background Technology

[0002] A thermal battery is a thermally activated primary battery that uses its own heating system to melt a non-conductive solid inorganic salt electrolyte into an ion-conductive electrolyte layer, thus putting the battery into operation. A thermal battery consists of several individual cells connected in series and parallel to form a stack, which is then encased in an insulating material and sealed. During normal operation, the core of the thermal battery is at a high temperature of 400-600°C, accompanied by gas production and thermal expansion, while the internal pressure inside the casing is typically below 1 MPa. Thermal batteries can be designed with a voltage range of 2V to 750V. As a disposable molten salt battery operating at high temperatures, its high-temperature characteristics make it more prone to thermal runaway, and thermal runaway poses a significant risk. Thermal runaway typically involves heat accumulation, temperature spikes, accelerated reactions, and system collapse, ultimately potentially leading to catastrophic consequences such as electrolyte leakage, casing bulging and rupture, large-scale internal ablation, and battery self-destruction. Therefore, the performance of thermal batteries in safety tests such as short circuit, reverse charging, explosion, thermal abuse, and insulation breakdown is a key focus for researchers. In these safety tests, the internal voltage, temperature, pressure, and gas composition of the battery fluctuate rapidly and violently. The instantaneous short circuit current of thermal batteries can reach more than 3000A. In extreme cases during safety tests, the center temperature of the thermal battery failure point can reach more than 2000℃, and the pressure can increase dramatically to more than 10MPa in a very short time (<1s). It is usually accompanied by violent combustion of the negative electrode active lithium and continuous splashing of solid powder and highly corrosive molten salt with the airflow.

[0003] Conventional safety tests focus only on a single variable among indicators such as gas, temperature, and voltage curves, lacking continuous high-sampling tracking of rapidly changing test processes and accurate measurement of material changes in highly corrosive molten salt environments. Therefore, the real-time and accurate acquisition and analysis of multi-dimensional data fusion states composed of various real-time data during thermal battery safety tests is of crucial significance for the study of thermal battery reaction mechanisms and safety.

[0004] CN117968927A discloses a device and method for real-time measurement of internal gas pressure in a thermal battery, capable of testing the trend of internal gas pressure changes before and after activation and during operation. This prior art involves testing the change of a single parameter—gas pressure—before and after activation and during normal operation. The test chamber is sealed, allowing only the acquisition of gas pressure data. No gas manipulation is performed, and there are no structures for gas extraction, collection, or component detection. The chemical composition of the gas produced by the thermal battery cannot be determined, failing to meet the requirements for high-temperature, high-pressure gas extraction in safety tests and lacking any safety testing functionality. Furthermore, the gas pipeline is susceptible to corrosion and failure due to splashed molten salt during thermal runaway.

[0005] CN110515000B is an integrated battery thermal runaway testing system that can perform flame-heated battery runaway testing, electrically heated battery runaway testing, and short-circuit-induced battery thermal runaway testing on various types of single cells and small battery packs. It can also be expanded to test the behavior of battery runaway caused by overcharging and over-discharging.

[0006] CN113533971B discloses a power battery needle-triggered thermal runaway system capable of gas collection. This system can complete the needle-triggered thermal runaway behavior of a lithium-ion battery in a confined space and successfully collect the gas released during the thermal runaway process, and perform component analysis through a gas analysis device.

[0007] CN118914903B describes a battery internal safety testing method, apparatus, equipment, and storage medium. By simulating cell displacement and compression caused by impact, combined with real-time monitoring of phenomena and data analysis within the battery, it can effectively evaluate the safety performance of a battery under extreme scenarios.

[0008] The aforementioned existing technologies include testing systems for thermal runaway caused by heating, overcharging, over-discharging, nail penetration, and impact on conventional batteries. Structurally, all of these systems involve placing the battery in a sealed cavity for thermal runaway testing. However, the failure modes and phenomena of conventional lithium-ion batteries differ significantly from those of thermal batteries. The peak thermal runaway temperature of lithium-ion batteries is approximately 1000°C, far lower than the core temperature of the thermal battery failure point. There is no testing phenomenon involving high-temperature powder or highly corrosive molten salt sputtering. The external cavity mode suffers from problems such as gas contamination, delayed results, difficulty in obtaining test results in real time, incompatibility with the thermal battery structure, and potential explosion hazards. An integrated testing system that can coordinate and accurately measure relevant parameters such as internal gases of thermal batteries under different operating conditions and safety test conditions is a blank area. Summary of the Invention

[0009] To address the technical problems existing in the prior art, this invention provides a thermal battery safety testing system with gas collection and analysis functions. It establishes an integrated system that can perform extreme safety tests on sealed thermal batteries through closed-loop collaborative control of the controller. The system separates and collects the internal gases of the thermal battery at each stage of the test process for real-time analysis, providing basic data support for the study of thermal battery safety models and internal gas conversion mechanisms.

[0010] The present invention is achieved through the following technical solution: a thermal battery safety test system with gas collection and analysis function, comprising: a thermal battery under test, a battery performance testing device, a safety test device, a gas separation and collection device, a gas analysis instrument, and a central control analysis and processing module; The safety testing device has components and functions for conducting short-circuit, reverse charging, explosion, thermal abuse, and insulation breakdown tests on the thermal battery. The tested thermal battery is a sealed thermal battery module composed of multiple individual cells connected in series and parallel. The outer casing of the thermal battery has at least one gas interface that connects the thermal battery to the gas pipeline. The battery performance testing device includes a programmable power supply, a DC electronic load and a data acquisition unit, which are electrically connected to the thermal battery under test and are used to activate the thermal battery under test and make it operate under specified conditions or discharge profiles. The programmable power supply is used to output activation electrical signals to the tested thermal battery according to a specified timing sequence; The DC electronic load is used to discharge the tested thermal battery according to a specified discharge profile, or to charge the tested thermal battery with a specified current in a reverse charging test. The data acquisition device is used to collect the voltage, current, temperature and air pressure signals of the tested thermal battery in real time and transmit them to the central control analysis and processing module in real time.

[0011] The safety testing device includes an electric furnace, a relay, and a temperature measuring device, which are physically or electrically connected to the thermal battery under test according to the test requirements, so as to enable the thermal battery under test to carry out the test according to the specified safety test items. The electric furnace can be heated according to a program or command from the central control analysis and processing module to carry out the explosion test of the tested thermal battery or to create a thermal abuse test environment. The relay is connected to the positive and negative terminals of the tested thermal battery or to the terminal post and the internal metal parts of the battery through a circuit. Under the signal control of the central control analysis and processing module, it performs short circuit test or insulation breakdown test. The temperature measuring device includes a thermocouple and an infrared thermometer. The thermocouple is attached to the surface of the thermal battery under test or a designated position in the safety test system to collect temperature signals and transmit them to the data acquisition unit. The infrared thermometer is set at a specific position in the system to monitor the temperature distribution changes of the thermal battery during the test. The gas separation and collection device includes a gas-liquid-solid three-phase product buffer separator, a pressure sensor, a solenoid valve, a vacuum pump, a gas collection container, an inert gas cylinder, a pressure relief device, and gas pipelines connecting each component. These pipelines are connected to the gas interface of the thermal battery under test and the gas analysis instrument, respectively. The device is used to separate and export the gas generated by the thermal battery under test during the safety test, and to transport the collected gas to the gas analysis instrument.

[0012] The gas-liquid-solid three-phase product buffer separator integrates an inertial separator, a molten salt buffer settling chamber, and a high-temperature corrosion-resistant ceramic filter. It achieves high-temperature gas buffer separation, molten product cooling and capture, and solid particulate matter filtration and collection functions. It effectively separates gas-liquid-solid three-phase products and purifies the mixed gas, thereby buffering the impact of gas waves, intercepting high-temperature residues, and preventing high-pressure deflagration from damaging the precision gas analyzer.

[0013] Furthermore, the inertial separator is a separation device for heterogeneous systems in the chemical industry. In this invention, the inertial separator is integrated at the front end of the gas-liquid-solid three-phase product buffer separation device, and adopts one of the following: collision type, reflux type, inertial settling type, louver type, and impact type. The internal structure should be made of high-temperature resistant metal or alloy or use a coating that is resistant to high-temperature and strong corrosive molten salt corrosion. The coating material is one or more combinations of BN ceramic, high-purity Al2O3 ceramic, HfO2 ceramic, and ZrO2 ceramic. Furthermore, the molten salt buffer settling chamber is a multifunctional buffer container that utilizes the volume expansion effect of the chamber to forcibly decelerate the multiphase mixed gas flow with high velocity, high temperature, and high pressure in the preceding stage. It utilizes physical mechanisms such as gravity settling, inertial separation, and heat exchange to achieve preliminary separation of the gas-liquid-solid three phases, stabilize the gas flow pressure and flow, and cool down and dissipate energy. It adopts a horizontal cylindrical configuration with an effective volume of 80-250mL, a chamber length-to-diameter ratio of L / D=2.5-3.5, and a designed average gas flow velocity of ≤0.5m / s. The internal structure should be made of high-temperature resistant metals or alloys or use a coating that is resistant to high-temperature and highly corrosive molten salt corrosion. The coating material is one or a combination of BN ceramics, high-purity Al2O3 ceramics, HfO2 ceramics, and ZrO2 ceramics.

[0014] Furthermore, the internal structure of the molten salt buffer settling chamber includes an integral gradually expanding chamber, a bottom molten salt accumulation tank, and a top staggered gas baffle. At the inlet, the airflow is decelerated by the abrupt change in the cross-sectional area of ​​the chamber itself. An arc-shaped accumulation tank with a depth of 20-30mm is set along the entire length of the bottom of the chamber to collect the settled high-temperature molten salt and solid particles. The gas baffles are fixed at the top of the chamber in an alternating manner, which forces the airflow to travel horizontally around the chamber along an "S" shaped path, thereby prolonging the airflow residence time and promoting particle settling.

[0015] The pressure sensor is connected to the gas pipeline to acquire the gas pressure change inside the tested thermal battery and convert it into an electrical signal that is transmitted to the data acquisition unit. The sampling mode can be controlled and adjusted. The solenoid valve is installed on the gas pipeline and is used to control the gas flow under the command of the central controller in order to collect gas at a specified time point. The vacuum pump is connected to the gas pipeline and is used to create a negative pressure environment or perform gas replacement on the gas pipeline and the inside of the thermal battery under test in a controlled manner before the test. The gas collection container is connected to the gas pipeline and is used to collect gas for subsequent analysis. The inert gas cylinder is connected to the gas pipeline and is used to fill the tested thermal battery and the gas pipeline with inert gas. The inert gas is used to replace the gas inside the tested thermal battery or as a gas carrier for dynamic gas transfer and compensation. The pressure relief device employs one or more of the following: rupture disc, high-temperature spring-loaded pressure relief valve, and shear pin type pressure relief cover plate. Under specific pressure, the pressure relief device is designed through mechanical structure to achieve rapid pressure relief. The gas analyzer is used to analyze the composition and changes of the gas transmitted in the gas pipeline in real time, so as to obtain the content ratio of the gas at different time points.

[0016] The central control analysis and processing module includes a control unit and a parameter coupling analysis unit. The control unit is used to coordinate and control the aforementioned devices and components to advance the safety test process according to a predetermined sequence or manual settings. The parameter coupling analysis unit is used to receive multiple parameters such as gas component concentration, gas pressure, and chamber temperature from the data acquisition device and the gas analysis instrument, and to calculate state quantitative indicators such as gas production rate and temperature rise rate in real time. It analyzes and establishes a time-series coupling parameter database, and constructs a multi-dimensional data fusion model through a multi-factor association algorithm for predicting the progress of the safety test and identifying hidden safety risks of the thermal battery in advance.

[0017] Furthermore, the pressure sensor has an external hardware synchronous trigger sampling function, and uses a fixed sampling rate for sampling before the gas pressure changes. When the central control analysis and processing module identifies the gas composition change characteristics of thermal runaway, the characteristics of the gas pressure rise curve, and the temperature change point, it automatically triggers the pressure sensor to switch to high-speed sampling mode, which can realize the acquisition of microsecond-level transient gas production peak data without omission.

[0018] Furthermore, the central control analysis and processing module uses the gas pressure data as an input variable and links it with each component of the gas separation and collection device collection circuit. By monitoring the gas pressure change inside the thermal battery in real time and combining it with the ideal gas state equation to dynamically calculate the gas production rate and cumulative gas production, the module controls the solenoid valve and the inert gas cylinder to perform gas pressure compensation and correction for the gas lost during the external collection process.

[0019] Furthermore, during the intense gas generation phase of the safety test, the central control analysis and processing module controls the opening of the solenoid valve and the opening and closing of the vacuum pump to perform adaptive gas buffer regulation. In conjunction with the pressure relief device, it avoids high-pressure backflow, gas pipe rupture, sensor over-range breakdown, and gas component concentration detection distortion caused by instantaneous pulse pressure gas flow impact under extreme operating conditions, thereby preventing safety accidents.

[0020] The advantages and positive effects of this invention are: 1. The thermal battery safety testing system of the present invention can test thermal batteries under specified operating conditions or safety test conditions. Through the technical solution of the present invention, safety tests can be carried out while keeping the test container sealed and personnel isolated. The battery status can be monitored in real time, and the changes of data such as thermal battery voltage, current, capacity, surface temperature, test progress, and internal gas pressure over time can be tracked during the test process, providing technical support for accumulating basic thermal battery data and mechanism analysis.

[0021] 2. The technical solution of the present invention can safely and quickly separate and collect gases under specific conditions or pressure ranges of thermal batteries during safety tests, and conduct real-time gas composition analysis, providing data support for exploring the gas generation components and reaction mechanisms in different safety test processes of thermal batteries.

[0022] 3. The technical solution of the present invention can link and control the performance verification device, the safety test device, and the gas separation and sampling analysis device, and construct a closed-loop system of real-time perception-intelligent regulation-dynamic compensation, which solves the long-standing technical problem in thermal battery safety testing of "the inability to obtain accurate and correlated multidimensional data under extreme and transient conditions". Attached Figure Description

[0023] Figure 1 This is a structural diagram of a preferred embodiment of the present invention.

[0024] Figure 2 This is a schematic diagram of a gas-liquid-solid three-phase product buffer separator.

[0025] In the diagram, A - programmable power supply, B - DC electronic load, C - data acquisition unit, D - measured thermal battery, E - inert gas cylinder, F - temperature measuring device, G - relay, H - electric furnace, I - pressure sensor, J - gas collection container, K - vacuum pump, L1 - first solenoid valve, L2 - second solenoid valve, L3 - third solenoid valve, L4 - fourth solenoid valve, L5 - fifth solenoid valve, M - gas analyzer, N - central control analysis and processing module, O - gas-liquid-solid three-phase product buffer separator, P - gas pipeline, Q - pressure relief device, O1 - inlet pipe, O2 - inertial separator, O3 - molten salt buffer settling chamber, O3a - top staggered gas baffle, O3b - bottom molten salt accumulation tank, O3c - integral gradually expanding cavity, O4 - high temperature corrosion resistant ceramic filter, O5 - outlet pipe. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0027] The thermal battery safety testing system with gas collection and analysis function of the present invention includes: the thermal battery under test, the battery performance testing device, the safety testing device, the gas separation and collection device, the gas analysis instrument, and the central control analysis and processing module.

[0028] The safety testing device has components and functions for performing short-circuit, reverse charging, explosion, thermal abuse, and insulation breakdown tests on the thermal battery.

[0029] The tested thermal battery is a sealed thermal battery module composed of multiple individual cells connected in series and parallel. The tested thermal battery has terminals for a thermal battery activation circuit and an output circuit. The battery can be activated by an electrical signal input to the activation circuit and output electrical energy to the outside through the output circuit terminals. The outer casing of the thermal battery under test is machined with at least one gas interface connecting the thermal battery and the gas pipeline. Furthermore, the outer shell material of the tested thermal battery is one or more of molybdenum and molybdenum alloys, tungsten and tungsten alloys, tantalum and tantalum alloys, niobium and niobium alloys, rhenium and rhenium alloys, or one or more of iron and iron alloys, copper and copper alloys, titanium and titanium alloys combined with a ceramic thermal barrier coating to achieve high pressure resistance sealing function and high temperature molten salt corrosion resistance. The thermal battery under test is physically connected to the safety testing device via a wiring connection or fixed installation, so that the thermal battery can be tested according to the specified safety test items. The tested thermal battery is connected to a gas pipeline and a gas separation and collection device, which is connected to a gas analysis instrument via a gas pipeline. This instrument is used to extract and collect the gas from the thermal battery under specified operating conditions and safety test items, and to analyze its composition and changes in real time.

[0030] The battery performance testing device includes a programmable power supply, a DC electronic load, and a data acquisition unit, which are electrically connected to the thermal battery under test and are used to activate the thermal battery under test and make it operate under specified conditions or discharge profiles.

[0031] The programmable power supply is used to output activation electrical signals to the tested thermal battery according to a specified timing sequence.

[0032] The DC electronic load is used to discharge the tested thermal battery according to a specified discharge profile, or to charge the tested thermal battery with a specified current in a reverse charging test.

[0033] The data acquisition device is used to collect the voltage, current, temperature and air pressure signals of the tested thermal battery in real time and transmit them to the central control analysis and processing module in real time.

[0034] The safety testing device includes an electric furnace, a relay, and a temperature measuring device, which are physically or electrically connected to the thermal battery under test according to the test requirements, so as to enable the thermal battery under test to carry out the test according to the specified safety test items.

[0035] The electric furnace can be heated according to a program or command from the central control analysis and processing module to carry out the explosion test of the tested thermal battery or to create a thermal abuse triggering test environment. Furthermore, the electric furnace is one of the following: an electric heating oven, a forced-air drying oven, a muffle furnace, or a high-temperature sintering furnace, with an upper limit of operating temperature of 2200℃, and has a high-temperature molten salt corrosion resistant lining.

[0036] The relay is connected to the positive and negative terminals of the tested thermal battery or to the terminal post and the internal metal parts of the battery through a circuit, and performs short circuit test or insulation breakdown test under the signal control of the central control analysis and processing module. Furthermore, the rated current of the relay is greater than 3000A, and it uses one or more of the following methods for arc extinguishing: magnetic blowout arc extinguishing, grid arc extinguishing, narrow slit arc extinguishing, arc extinguishing cover arc extinguishing, multi-breakpoint arc extinguishing, permanent magnet arc extinguishing, vacuum arc extinguishing, gas-filled arc extinguishing, and RC absorption arc extinguishing. The pull-in time and release time are both no more than 50ms.

[0037] The temperature measuring device includes a thermocouple and an infrared thermometer. The thermocouple is attached to the surface of the tested thermal battery or a designated position in the safety test system to collect temperature signals and transmit them to the data acquisition unit. The infrared thermometer is set at a specific position in the system to monitor the temperature distribution changes on the surface of the tested thermal battery during the test process. Furthermore, the thermocouple should be resistant to molten salt corrosion, and an ultra-thin ceramic isolation structure should be used at the measuring end to isolate it from the molten salt of the thermocell. The ceramic layer thickness is 20μm~200μm, and the ceramic isolation structure material can be one of alumina, magnesium oxide, zirconium oxide, silicon nitride, silicon carbide, and boron nitride. The maximum temperature range should be no less than 2000℃. Furthermore, the infrared thermometer should adopt a multi-range design, with a high-temperature range of not less than 1000℃, and have the function of real-time image data transmission.

[0038] The gas separation and collection device includes a gas-liquid-solid three-phase product buffer separator, a pressure sensor, a solenoid valve, a vacuum pump, a gas collection container, an inert gas cylinder, a pressure relief device, and gas pipelines connecting each component. These pipelines are connected to the gas interface of the thermal battery under test and the gas analysis instrument, respectively. The device is used to separate and export the gas generated by the thermal battery under test during the safety test, and to transport the collected gas to the gas analysis instrument.

[0039] Furthermore, the gas pipeline adopts a high-pressure explosion-proof seamless metal pipeline combined with a high-pressure sealing sleeve structure, which can withstand a static pressure of not less than 15MPa and a temperature of not less than 1500℃. Furthermore, the gas pipeline material should be one or a combination of molybdenum and molybdenum alloys, tungsten and tungsten alloys, tantalum and tantalum alloys, niobium and niobium alloys, rhenium and rhenium alloys, iron and iron alloys, copper and copper alloys, titanium and titanium alloys, and ceramic thermal barrier coatings. The gas-liquid-solid three-phase product buffer separator integrates an inertial separator, a molten salt buffer settling chamber, and a high-temperature corrosion-resistant ceramic filter. It achieves high-temperature gas buffer separation, molten product cooling and capture, and solid particulate matter filtration and collection functions. It effectively separates gas phase decomposition products, liquid phase high-temperature molten salt, and solid phase sputtering dust, while purifying and retaining the mixed gas. This buffers the impact of gas waves, intercepts high-temperature residues, and avoids high-pressure deflagration that could damage the precision gas analyzer.

[0040] The inertial separator adopts one of the following types: collision type, reflux type, inertial settling type, louver type, and impact type. The internal structure should be made of high-temperature resistant metal or alloy or use a coating that is resistant to high-temperature and strong corrosive molten salt corrosion. The coating material is one or more combinations of BN ceramic, high-purity Al2O3 ceramic, HfO2 ceramic, and ZrO2 ceramic. The molten salt buffer settling chamber relies on a large-volume pressure-stabilizing settling chamber to force the high-velocity gas, droplets and dust in the front stage to slow down, and uses the chamber volume to suppress the pressure oscillation caused by deflagration, cool down and dissipate energy, so as to achieve settling separation and airflow pressure stabilization. Furthermore, the molten salt buffer settling chamber adopts a horizontal cylindrical configuration with an effective volume of 80-250 mL, a length-to-diameter ratio of L / D = 2.5-3.5, a design average airflow velocity of ≤0.5 m / s, and the internal structure should be made of high-temperature resistant metals or alloys or use a coating that is resistant to high-temperature and highly corrosive molten salt corrosion. The coating material should be one or more combinations of BN ceramics, high-purity Al2O3 ceramics, HfO2 ceramics, and ZrO2 ceramics. Furthermore, the internal structure of the molten salt buffer settling chamber includes an integral gradually expanding chamber, a bottom molten salt accumulation tank, and a top staggered gas baffle. At the inlet, the airflow is decelerated by the abrupt change in the cross-sectional area of ​​the chamber itself. An arc-shaped accumulation tank with a depth of 20-30mm is set along the entire length of the bottom of the chamber to collect the settled high-temperature molten salt and solid particles. The gas baffles are fixed at the top of the chamber in an alternating manner, forcing the airflow to travel horizontally around the chamber along an "S" shaped path, which promotes particle settling while extending the airflow residence time.

[0041] The high-temperature corrosion resistant ceramic filter consists of an inner supporting substrate and a surface filter membrane. The inner supporting substrate has a pore size of 10–30 μm and a porosity of 25%–55%, while the surface filter membrane has a pore size of 1–3 μm and a porosity of 20%–50%. Furthermore, the inner support substrate of the high-temperature corrosion resistant ceramic filter is made of a high-temperature resistant and highly thermally conductive metal or alloy, or one or more of the following materials: BN ceramic, high-purity Al2O3 ceramic, HfO2 ceramic, ZrO2 ceramic, and SiC ceramic, which are resistant to high temperature and molten salt corrosion. The surface filter membrane is made of one or more of the following materials: BN ceramic, high-purity Al2O3 ceramic, HfO2 ceramic, ZrO2 ceramic, and SiC ceramic, which are used as the main material to rapidly cool the gas during the filtration process.

[0042] The pressure sensor is connected to the gas pipeline to acquire the gas pressure change inside the tested thermal battery and convert it into an electrical signal that is transmitted to the data acquisition unit. The sampling mode can be controlled and adjusted. Furthermore, the pressure sensor has an external hardware synchronous trigger sampling function. Before a sudden change in air pressure, it uses a fixed sampling rate for sampling. After the test is triggered, it starts a high sampling rate working mode according to the instructions of the central control analysis and processing module.

[0043] The solenoid valve is installed on the gas pipeline and is used to control the gas flow under the command of the central controller in order to collect gas at a specified time point. Furthermore, the solenoid valve has a gas explosion-proof function and can tolerate a maximum internal pressure of not less than 15MPa.

[0044] The vacuum pump is connected to the gas pipeline and is used to create a negative pressure environment or perform gas replacement in a controlled manner on the gas pipeline and inside the thermal battery under test.

[0045] The gas collection container is connected to the gas pipeline and is used to collect gas for subsequent analysis. Furthermore, the gas collection container can be a gas sampling bag, syringe, gas cylinder or similar product; Furthermore, the gas collection container should have a corrosion-resistant lining, and the lining material can be one or a combination of perfluoroplastics, semi-fluoroplastics, perfluororubber, and inorganic hard ceramic materials. The inert gas cylinder is connected to the gas pipeline and is used to fill the tested thermal battery and the gas pipeline with inert gas. The inert gas is used to replace the gas inside the tested thermal battery or as a gas carrier for dynamic gas transfer and compensation. Furthermore, the inert gas cylinder can contain inert gases such as argon, helium, neon, and nitrogen.

[0046] The pressure relief device employs one or more of the following: rupture disc, high-temperature spring-loaded pressure relief valve, and shear pin type pressure relief cover plate. Under specific pressure, the pressure relief device is designed through mechanical structure to achieve rapid pressure relief. Furthermore, the design critical pressure relief value of the pressure relief device is 5MPa~15MPa; Furthermore, the pressure relief device should be located in the upper gas phase region of the gas pipeline, and baffles should be installed to prevent molten salt blockage; The gas analyzer is used to analyze the composition and changes of the gas transmitted in the gas pipeline in real time, and to obtain the content percentage of the gas at different time points. Furthermore, the gas analyzer can detect gas components using one or more of the following methods: electrochemical detection, thermal conductivity detection, magnetic oxygen detection, infrared spectroscopy, ultraviolet spectroscopy, laser spectroscopy, photoionization sensing, flame ionization detection, semiconductor detection, chromatographic analysis, and mass spectrometry.

[0047] The central control analysis and processing module includes a control unit and a parameter coupling analysis unit. The control unit is used to coordinate and control the aforementioned devices and components to advance the safety test process according to a predetermined sequence or manual settings. The parameter coupling analysis unit is used to receive multiple parameters such as gas component concentration, gas pressure, and chamber temperature from the data acquisition device and the gas analysis instrument, and to calculate state quantitative indicators such as gas production rate and temperature rise rate in real time. It analyzes and establishes a time-series coupling parameter database, and constructs a multi-dimensional data fusion model through a multi-factor association algorithm for predicting the progress of the safety test and identifying hidden safety risks of the thermal battery in advance.

[0048] Furthermore, the central control analysis and processing module receives data from the data acquisition unit and analyzes it in real time. When it identifies the characteristics of gas component changes, pressure rise curve features, and temperature change points during thermal runaway, it automatically adjusts the sampling mode of the pressure sensor to a high-speed sampling mode, which can achieve the acquisition of microsecond-level transient gas production peak data without omission.

[0049] Furthermore, the central control analysis and processing module uses the gas pressure data as an input variable and links it with each component of the gas separation and collection device's collection loop. By monitoring the gas pressure changes inside the thermal battery in real time and dynamically calculating the gas production rate and cumulative gas production using the ideal gas law, the module controls the solenoid valve and the inert gas cylinder to perform gas pressure compensation and correction for the gas lost during the external collection process. This eliminates sampling deviations caused by internal pressure differences, thus achieving a closed loop of internal pressure monitoring, gas production calculation, and sampling compensation.

[0050] Furthermore, during the intense gas generation phase of the safety test, the central control analysis and processing module controls the opening of the solenoid valve and the opening and closing of the vacuum pump to perform adaptive gas buffer regulation. In conjunction with the pressure relief device, it avoids high-pressure backflow, gas pipe rupture, sensor over-range breakdown, and gas component concentration detection distortion caused by instantaneous pulse pressure gas flow impact under extreme operating conditions, thereby preventing safety accidents.

[0051] To further understand the invention's content, features, and effects, the following embodiments are provided, and detailed descriptions are given below in conjunction with the accompanying drawings: Please see Figure 1 and Figure 2 The thermal battery safety test system with gas collection and analysis function includes the thermal battery under test (D), battery performance testing device, safety testing device, gas separation and collection device, gas analysis instrument (M), and central control analysis and processing module (N). The battery performance testing device includes a programmable power supply A, a DC electronic load B, and a data acquisition unit C. The programmable power supply A and the DC electronic load B are used to activate the tested thermal battery D according to a specified time sequence and discharge the tested thermal battery D according to a specified discharge profile or charge the tested thermal battery D in a reverse charging test. The data acquisition unit C can collect the voltage signal of the tested thermal battery D, the electrical signal of the pressure sensor I, the electrical signal of the temperature measuring device F, and the discharge or reverse charging current signal. The safety testing device includes an electric furnace H, a relay G, and a temperature measuring device F. The electric furnace H is used to heat up according to a program or command from the central control analysis and processing module N to burn out an inactive thermal battery D or to create a thermal abuse environment to trigger thermal runaway of the thermal battery D. The relay G is used to connect to the positive and negative terminals of the thermal battery D under the control of the central control analysis and processing module N to conduct a short circuit test or to connect the terminal to the internal metal parts of the thermal battery D to conduct an insulation breakdown test. The thermocouple in the temperature measuring device F is attached to the required position in the test system. It is usually used to attach to the surface of the thermal battery D and transmit the collected signal to the data acquisition unit C through the line. The infrared thermometer in the temperature measuring device F is set at a designated position in front of the thermal battery D to collect temperature changes to determine the state of the thermal battery.

[0052] The gas separation and collection device includes a pressure sensor I, a first solenoid valve L1, a second solenoid valve L2, a third solenoid valve L3, a fourth solenoid valve L4, a fifth solenoid valve L5, a gas-liquid-solid three-phase product buffer separator O, a pressure relief device Q, a vacuum pump K, a gas collection container J, an inert gas cylinder E, and gas pipelines P for interconnecting the various devices. The gas-liquid-solid three-phase product buffer separator O integrates an inertial separator O2, a molten salt buffer settling chamber O3, and a high-temperature corrosion-resistant ceramic filter O4. It is connected to an inlet pipe O1 and an outlet pipe O5 at the front and rear ends, respectively, to achieve high-temperature gas buffering and separation, molten product cooling and capture, and solid particulate matter filtration and collection. The molten salt buffer settling chamber O3 consists of a top staggered gas baffle O3a, a bottom molten salt accumulation tank O3b, and an overall gradually expanding cavity O3c.

[0053] The pressure sensor I can acquire the internal pressure change of the tested thermal battery D and convert it into an electrical signal, which is then transmitted to the data acquisition unit C via a line. The first solenoid valve L1 is a valve that controls the output gas from the inert gas cylinder E, used to control the filling of the inert gas cylinder E with inert gas in the tested thermal battery D and the gas pipeline P. The inert gas can be used as a replacement gas or as a gas carrier for dynamic gas transfer and compensation. The second solenoid valve L2 is the main valve for the output gas from the tested thermal battery D, which can control the gas collection and analysis during the experiment. The third solenoid valve L3 is a valve that controls gas collection, with its rear end connected to the gas collection container J to control the gas to flow into the collection device for storage under specified conditions. The fourth solenoid valve L4 is used to control... The gas flows into the gas analyzer M to control the gas for real-time analysis under preset conditions; the fifth solenoid valve L5 is connected to the vacuum pump K at its rear end to control the exhaust of the vacuum pump K and control the vacuum level of the pipeline; the pressure relief device Q is used to open when the pressure reaches the preset condition to guide the rapid release of gas; the gas collection container J can collect gas for subsequent analysis and research; the gas-liquid-solid three-phase product buffer separator O integrates an inertial separator, a molten salt buffer settling chamber, and a high-temperature corrosion resistant ceramic filter to achieve high-temperature gas buffer separation, molten product cooling and capture, and solid particulate matter filtration and collection functions, effectively separating gas phase decomposition products, liquid phase high-temperature molten salt, and solid phase sputtering dust, while purifying and retaining the mixed gas.

[0054] The gas analyzer M can be controlled by the central control and analysis processing module N to analyze the composition and changes of the gas transmitted in the gas pipeline P in real time, and obtain the content percentage of the gas at different time points.

[0055] The central control analysis and processing module N includes a control unit and a parameter coupling analysis unit. The control unit is connected to the programmable power supply A, DC electronic load B, electric furnace H, relay G, first solenoid valve L1, second solenoid valve L2, third solenoid valve L3, fourth solenoid valve L4, and fifth solenoid valve L5 for controlling the test process and performing real-time regulation. The parameter coupling analysis unit is connected to the data acquisition unit C and the gas analysis instrument M to realize functions such as gas production estimation, test prediction, sampling compensation, and risk identification.

[0056] Example 1 This embodiment provides a test method for insulation breakdown of a high-voltage thermal battery. The insulation breakdown test process and the gas collection and analysis process include the following steps: 1) The system is equipped with a programmable power supply A, a data acquisition unit C, a thermal battery under test D, a temperature measuring device F, a relay G, a pressure sensor I, a second solenoid valve L2, a fourth solenoid valve L4, a fifth solenoid valve L5, a vacuum pump K, a gas analyzer M, a central control analysis and processing module N, a gas-liquid-solid three-phase product buffer separator O, a gas pipeline P, and a pressure relief device Q. The gas analyzer M uses an electrochemical detection method to detect gas components in real time in situ. The casing of the thermal battery under test D is made of titanium alloy with a SiC ceramic thermal barrier coating, and the gas pipeline P is made of tungsten alloy.

[0057] 2) In the initial state, the second solenoid valve L2, the fourth solenoid valve L4, and the fifth solenoid valve L5 are all closed, the tested thermal battery D is in an inactive state, and the thermocouple of the temperature measuring device F is attached to the required position of the test system to collect temperature information. 3) The C terminal of the data acquisition unit is connected to the D output terminal of the tested thermal battery, the I signal line of the pressure sensor, and the F signal line of the temperature measuring device to collect test data. The data acquisition unit C will summarize and transmit the data to the central control analysis and processing module N. 4) The output terminal of the tested thermal battery D and the lead-out terminal of the internal metal structure are connected to the relay G via wires; 5) The vacuum pump K and the fourth solenoid valve L4 and the fifth solenoid valve L5 are opened through the central control analysis and processing module N to purge the gas in the downstream section of the gas pipeline P. 6) The vacuum pump K and the fifth solenoid valve L5 are shut down through the central control analysis and processing module N. The programmable power supply A is activated to activate the thermal battery D under test. The thermal battery D under test is in no-load condition. According to the test plan, the second solenoid valve L2 is opened and the relay G is controlled to make the output terminal of the thermal battery D under test connected to the lead-out terminal of the internal metal structure, causing the insulation failure phenomenon. 7) The tested thermal battery D experiences a partial short circuit discharge and thermal runaway, instantly generating a large amount of gas. Molten salt and powder are ejected along with the gas. Pressure sensor I switches to high-speed sampling mode. After passing through the gas-liquid-solid three-phase product buffer separator O, the molten salt and powder are fixed. The gas reaches the gas analyzer M through the subsequent gas pipeline P at a lower pressure. The gas analyzer M analyzes the gas composition in real time and transmits the results to the central control analysis and processing module N. 8) The central control analysis and processing module N analyzes the various parameters transmitted by the data acquisition unit C and the gas analyzer M in real time, and tracks and controls the experimental process.

[0058] Example 2 This embodiment provides a test method for thermal abuse testing of a large-capacity thermal battery. The thermal abuse test process and the gas collection and analysis process include the following steps: 1) The system is equipped with a programmable power supply A, a DC electronic load B, a data acquisition unit C, a thermal battery under test D, a temperature measuring device F, a pressure sensor I, an inert gas cylinder E, a first solenoid valve L1, a second solenoid valve L2, a third solenoid valve L3, a fourth solenoid valve L4, a fifth solenoid valve L5, a vacuum pump K, a gas analyzer M, a central control analysis and processing module N, a gas-liquid-solid three-phase product buffer separator O, an electric furnace H, a gas collection container J, a gas pipeline P, and a pressure relief device Q. The gas analyzer M uses gas chromatography analysis technology to detect gas components in real time in situ. The casing of the thermal battery under test D is made of tungsten alloy, and the gas pipeline P is made of tungsten alloy.

[0059] 2) In the initial state, the first solenoid valve L1, the second solenoid valve L2, the fourth solenoid valve L4, and the fifth solenoid valve L5 are all closed, the tested thermal battery D is in an inactive state, the thermocouple of the temperature measuring device F is attached to the required position of the test system to collect temperature information, and the electric furnace H is set to the specified test temperature. 3) The C terminal of the data acquisition unit is connected to the D output terminal of the tested thermal battery, the I signal line of the pressure sensor, and the F signal line of the temperature measuring device to collect test data. The data acquisition unit C will summarize and transmit the data to the central control analysis and processing module N. 4) The output terminal of the tested thermal battery D is connected to the DC electronic load B terminal via a wire; 5) The vacuum pump K and the fourth solenoid valve L4 and the fifth solenoid valve L5 are opened through the central control analysis and processing module N to purge the gas in the downstream section of the gas pipeline P. 6) After the vacuum pump K and the fifth solenoid valve L5 are shut off by the central control analysis and processing module N, the thermal battery D to be tested is transferred to the electric furnace H. The programmable power supply A is then used to activate the thermal battery D. The thermal battery D is discharged at a specified profile under the control of the DC electronic load B. The second solenoid valve L2 is opened according to the test plan. The pressure sensor I collects the internal air pressure data in real time. The central control analysis and processing module N receives the air pressure and voltage data collected by the data acquisition unit C. When the air pressure or voltage value reaches the preset threshold, the pressure sensor I is controlled to switch to the high-speed sampling mode and the third solenoid valve L3 and the fourth solenoid valve L4 are opened. 7) When the tested thermal battery D experiences localized overheating, the internal battery stack melts rapidly, instantly generating a large amount of high-temperature liquid molten salt. Accompanied by a large amount of gaseous products, the products pass through the gas-liquid-solid three-phase product buffer separator O, where the molten salt is fixed. The gas reaches the gas collection container J and the gas analyzer M through the subsequent gas pipeline P at a lower pressure. After the gas collection container J stores a certain amount of gas, the third solenoid valve L3 is closed under control. The gas analyzer M analyzes the gas composition in real time and transmits the results to the central control analysis and processing module N. At the same time, the central control analysis and processing module N opens the first solenoid valve L1 as needed during the gas pressure drop, filling the tested thermal battery D with inert gas from the inert gas cylinder E, so that the internal gas pressure of the tested thermal battery D can always remain stable at a high level, avoiding deviations or termination of the test process caused by gas diversion. 8) The central control analysis and processing module N analyzes the various parameters transmitted by the data acquisition unit C and the gas analyzer M in real time, tracks and controls the experimental process, evaluates the experimental results, and provides a reference for subsequent experiments.

[0060] The embodiments of the present invention have been described in detail above, but the content described is only an embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the patent coverage of the present invention.

Claims

1. A thermal battery safety testing system with gas collection and analysis functions, characterized in that, It includes the thermal battery under test, battery performance testing device, safety testing device, gas separation and collection device, real-time gas analysis instrument, and central control analysis and processing module; The tested thermal battery has a sealed structure, and its outer shell is machined with at least one gas interface for connecting the interior of the thermal battery to a gas pipeline. The battery performance testing device is electrically connected to the tested thermal battery and is used to activate the tested thermal battery and make it operate under specified conditions or discharge profiles. The safety testing device is physically or electrically connected to the thermal battery under test, and is used to enable the thermal battery under test to conduct a safety test. The gas separation and collection device includes a gas-liquid-solid three-phase product buffer separator, a pressure sensor, a solenoid valve, a vacuum pump, a gas collection container, an inert gas cylinder, and a pressure relief device. It is connected to the gas interface of the tested thermal battery and the real-time gas analysis instrument. It is used to separate and export the gas generated by the tested thermal battery during the safety test, and to transport the collected gas to the real-time gas analysis instrument. The gas-liquid-solid three-phase product buffer separator integrates an inertial separator, a molten salt buffer settling chamber, and a high-temperature corrosion-resistant ceramic filter. This allows for high-temperature gas buffer separation, molten product cooling and capture, and solid particulate matter filtration and collection, purifying the gas to obtain a mixed gas. The gas real-time analysis instrument is used to analyze the composition and changes of the gas transmitted in the gas pipeline in real time; The central control analysis and processing module includes a control unit and a parameter coupling analysis unit, which are communicatively connected to the battery performance testing device, safety testing device, gas separation and collection device, and gas real-time analysis instrument. It is used to coordinate and control each device to advance the safety test process according to a predetermined sequence, and to analyze and process the collected parameters.

2. The thermal battery safety testing system with gas collection and analysis function according to claim 1, characterized in that, The outer shell of the tested thermal battery is made of one or more of the following materials: molybdenum and molybdenum alloy, tungsten and tungsten alloy, tantalum and tantalum alloy, niobium and niobium alloy, rhenium and rhenium alloy, or one or more of the following materials: iron and iron alloy, copper and copper alloy, titanium and titanium alloy, combined with a ceramic thermal barrier coating.

3. The thermal battery safety testing system with gas collection and analysis function according to claim 1, characterized in that, The battery performance testing device includes a programmable power supply, a DC electronic load, and a data acquisition unit. The programmable power supply is used to output activation electrical signals to the tested thermal battery according to a specified timing sequence; The DC electronic load is used to discharge the tested thermal battery according to a specified discharge profile, or to charge the tested thermal battery with a specified current in a reverse charging test. The data acquisition device is used to collect the voltage, current, temperature and air pressure signals of the tested thermal battery in real time and transmit them to the central control analysis and processing module in real time.

4. The thermal battery safety testing system with gas collection and analysis function according to claim 3, characterized in that, The safety testing device includes an electric furnace, a relay, and a temperature measuring device; The electric furnace can be heated according to a program or control command to carry out the test of the thermal battery explosion or to create a thermal abuse trigger test environment. The relay is connected to the positive and negative terminals of the tested thermal battery or to the terminal post and the internal metal parts of the battery through a circuit. Under the signal control of the central control analysis and processing module, it performs short circuit test or insulation breakdown test. The temperature measuring device includes a thermocouple and an infrared thermometer. The thermocouple is attached to the surface of the thermal battery under test or a designated location in the system to collect temperature signals and transmit them to the data acquisition unit. The infrared thermometer is set at a specific location in the system to monitor the temperature distribution changes of the thermal battery during the test.

5. The thermal battery safety testing system with gas collection and analysis function according to claim 4, characterized in that, The relay has a rated current greater than 3000A and uses one or more of the following methods for arc extinguishing: magnetic blowout arc extinguishing, grid arc extinguishing, narrow slit arc extinguishing, arc extinguishing cover arc extinguishing, multi-breakpoint arc extinguishing, permanent magnet arc extinguishing, vacuum arc extinguishing, gas-filled arc extinguishing, and RC absorption arc extinguishing. The pull-in time and release time are both no more than 50ms.

6. The thermal battery safety testing system with gas collection and analysis function according to claim 1, characterized in that, The gas pipeline adopts a high-pressure explosion-proof seamless metal pipeline combined with a high-pressure sealing ferrule structure, which can withstand a static pressure of not less than 15MPa and a temperature of not less than 1500℃; the gas pipeline is made of one or more of the following materials: molybdenum and molybdenum alloy, tungsten and tungsten alloy, tantalum and tantalum alloy, niobium and niobium alloy, rhenium and rhenium alloy, or one or more of the following materials: iron and iron alloy, copper and copper alloy, titanium and titanium alloy, combined with a ceramic thermal barrier coating.

7. The thermal battery safety testing system with gas collection and analysis function according to claim 1, characterized in that, The high-temperature corrosion resistant ceramic filter consists of an inner supporting substrate and a surface filter membrane. The pore size of the inner supporting substrate is 10-30 μm and the porosity is 25%-55%. The pore size of the surface filter membrane is 1-3 μm and the porosity is 20%-50%.

8. The thermal battery safety testing system with gas collection and analysis function according to claim 3, characterized in that, The pressure sensor is installed on the gas pipeline to acquire the gas pressure change inside the tested thermal battery and convert it into an electrical signal for transmission to the data acquisition unit. The solenoid valve is installed on the gas pipeline and is used to control the gas flow under the command of the central control analysis and processing module in order to collect gas at a specified time point. The vacuum pump is connected to the gas pipeline and is used to create a negative pressure environment or perform gas replacement on the gas pipeline and the inside of the thermal battery under test in a controlled manner before the test. The gas collection container is connected to the gas pipeline and is used to collect gas for subsequent analysis. The inert gas cylinder is connected to the gas pipeline and is used to fill the tested thermal battery and the gas pipeline with inert gas. The inert gas is used to replace the gas inside the tested thermal battery or to act as a gas carrier for dynamic gas generation and transfer.

9. The thermal battery safety testing system with gas collection and analysis function according to claim 3, characterized in that, The central control analysis and processing module control unit is used to uniformly coordinate and control the aforementioned devices and components to advance the safety test process according to a predetermined sequence or manual settings. The parameter coupling analysis unit of the central control analysis and processing module is used to receive gas component concentration, gas pressure, and cavity temperature parameters from the data acquisition unit and the real-time gas analysis instrument, and to calculate status indicators such as gas production rate and temperature rise rate in real time. When the central control analysis and processing module identifies the characteristics of gas component changes, gas pressure rise curve features, and temperature abrupt change points during thermal runaway, it automatically adjusts the sampling mode of the pressure sensor to a high-speed sampling mode to achieve the acquisition of microsecond-level transient gas production peak data without omission. The central control analysis and processing module uses the gas pressure data as an input variable and links it with each component of the collection circuit of the gas separation and collection device. By monitoring the gas pressure change inside the thermal battery in real time, it dynamically calculates the gas production rate and cumulative gas production by combining the ideal gas state equation, and controls the solenoid valve and the inert gas cylinder to perform gas pressure compensation and correction on the gas samples collected from the outside.

10. The thermal battery safety testing system with gas collection and analysis function according to claim 1, characterized in that, During the intense gas generation phase of the safety test, the central control analysis and processing module controls the opening of the solenoid valve and the opening and closing of the vacuum pump to perform adaptive gas buffer regulation. This, combined with the pressure relief device, prevents high-pressure backflow, gas pipe rupture, sensor over-range breakdown, and gas component concentration detection distortion caused by instantaneous pulse pressure gas flow impact under extreme conditions.

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