Adiabatic thermal sample cell structure for multi-phase multi-component sample and testing method

Abstract

The invention relates to the technical field of heat-insulating heat, in particular to a heat-insulating heat sample cell structure for a multi-phase multi-component sample and a testing method. The invention aims to solve the problems that the existing multiphase multicomponent sample is difficult to test, the temperature field in the sample cell is uneven, the gas introduction and collection are uncontrollable, the measurement and control system has deviation and the like. The device is composed of a dumbbell-shaped sample cell structure, an independent heating wire assembly, a gas pipeline system and an intelligent measurement and control system. The dumbbell-shaped sample cell expands the internal space and solves the problem of testing multiphase and multicomponent samples; the independent heating wire assembly is wound on two sides of the sample cell and can independently heat and control temperature, compensate heat loss and solve the problem of uneven temperature field; the gas pipeline system is communicated with the sample pool, so that phase medium separation and gas controllable introduction and collection are realized; the intelligent measurement and control system regulates and controls the whole measurement and control system and provides data support and safety guarantee for testing.

Description

Technical Field

[0001] The present invention relates to the technical field of adiabatic calorimetry, and particularly to an adiabatic calorimetry sample cell structure and a testing method for multi-phase and multi-component samples. Background Art

[0002] With the rapid development of materials science, adiabatic calorimetry technology, as a high-precision calorimetry method for studying the thermal stability of materials, has been widely used in the fields of materials science, energy research, etc. Adiabatic calorimetry technology can provide a nearly perfect adiabatic environment and effectively avoid the interference of environmental heat exchange. Existing adiabatic calorimetry technologies mostly target single-phase (such as solid phase or liquid phase) samples, and there is a lack of precise research on the thermal stability of common multi-phase and multi-component samples (such as high-nickel lithium-ion batteries, ternary cathode materials, etc.). Therefore, it is particularly important to study an adiabatic calorimetry technology for multi-phase and multi-component samples.

[0003] Traditional adiabatic calorimetry technologies mostly adopt a single sample cell structure, and monitor the real-time reaction of single-phase samples by controlling the temperature of the entire calorimetry system. Due to the significant differences in the physical and chemical properties of each phase inside multi-phase and multi-component samples and the complex interactions between components, it poses a severe challenge to the accurate measurement of the thermal stability of materials; moreover, multi-phase and multi-component materials are prone to phase changes during the heating process, and traditional adiabatic calorimetry technologies cannot meet the uniformity testing requirements of multi-phase and multi-component samples.

[0004] From the perspective of the sample cell structure dimension, the single sample cell structure has inherent deficiencies. In the traditional adiabatic calorimetry testing process, the entire sample cell structure is regarded as a whole, and the temperature measured by the temperature sensor is the real-time reaction temperature of the internal sample, which cannot track the single-phase temperature of multi-phase and multi-samples (such as gas-solid two-phase). In addition, the heat transfer mechanism of the single sample cell structure is imperfect, the internal temperature field distribution is uneven, and the temperature difference between the center and the edge is significant. To a certain extent, the point temperature measurement principle of the temperature sensor determines that there are deviations in the testing of the thermal stability of materials. The single sample cell structure is difficult to ensure the full contact of different phases for multi-phase and multi-component samples, restricting the reaction sufficiency, and thus affecting the accuracy and repeatability of the measurement results.

[0005] From the perspective of the test method, the traditional adiabatic calorimetry technology heats the sample cell in the form of heat conduction. It is difficult to accurately control the heating rate, and there is heat dissipation during the conduction process. The temperature sensor cannot accurately capture the dynamic changes of information such as phase transition and reaction critical temperature. The traditional adiabatic calorimetry test method has significant limitations. It can only carry out the thermal performance determination for a single isolated sample and cannot effectively explore the influence mechanism of the intervention of external substances on the thermal reaction process of the target sample. In a multiphase and multicomponent system, especially in the research related to lithium batteries, the interaction between different materials is crucial for the material performance and the overall performance of the battery. For example, in the study of the thermal stability of electrode materials, foreign substances such as ambient gases or electrolyte additives may cause changes in the thermal reaction path and kinetic characteristics of the sample. The single sample cell structure and the imperfect test method are likely to cause deviations in the test results of the material thermal stability and lose the guiding significance for preventing thermal runaway accidents. Summary of the Invention

[0006] Aiming at the deficiencies of the prior art, the present invention provides an adiabatic calorimetry sample cell structure and a test method for multiphase and multicomponent samples, which solve the problems of difficult testing of multiphase and multicomponent samples, uneven temperature field distribution inside the sample cell, uncontrollable gas introduction and collection, and deviation in the measurement and control system in the prior art.

[0007] In the first aspect of the present invention, an adiabatic calorimetry sample cell structure for multiphase and multicomponent samples is provided, including:

[0008] A sample cell body, the sample cell body is of a dumbbell-shaped structure, including two independent sample cell parts for respectively accommodating samples with different phase compositions;

[0009] A heating component, the heating component includes an independent heating wire, and the independent heating wire is tightly wound around the outside of the sample cell body for separately heating and controlling the temperature of the sample cell to compensate for heat dissipation and ensure uniform heating of the sample cell surface;

[0010] A gas pipeline system, the gas pipeline system is connected to the sample cell body for introducing and collecting gas during the sample reaction process;

[0011] A measurement and control system, the measurement and control system is used to monitor parameters such as temperature and pressure in the sample cell body in real time, and regulate the heating component and the gas pipeline system according to the monitoring results.

[0012] In the second aspect of the present invention, an adiabatic calorimetry test method for multiphase and multicomponent samples is provided. Using the above structure, it includes the following steps:

[0013] Step 1. Load the multiphase and multicomponent sample into the left cavity of the dumbbell-shaped sample cell. The dumbbell-shaped sample cell includes two independent sample cell parts for accommodating samples with different phase compositions respectively;

[0014] Step 2. Close the pressure relief valve and the switch gas valve in the gas pipeline system to ensure good airtightness of the whole device;

[0015] Step 3. Set the parameters of the adiabatic calorimetry experiment, start the heating component to heat the sample cell, detect the temperature in the sample cell in real time through the temperature sensor, and adjust the output power of the heating component according to the comparison between the measured temperature and the set temperature;

[0016] Step 4. After detecting that the sample starts to react, stop the active heating, adjust the output power of the heating component according to the temperature feedback measured by the temperature sensor, and track the temperature change in the sample cell in real time;

[0017] Step 5. Collect the gas generated during the reaction through the gas pipeline system, and monitor the pressure change in the sample cell through the pressure sensor;

[0018] Step 6. After the test, perform pressure relief and rapid cooling through the gas pipeline system.

[0019] Advantages of the present invention:

[0020] 1. By introducing the dumbbell-shaped sample cell structure, the present invention greatly improves the internal space of the sample cell, facilitates phase separation during the reaction of the multiphase and multicomponent sample, effectively expands the sample test range of the adiabatic calorimetry system, and provides the possibility for exploring the interaction between different substances in the multiphase and multicomponent system. Compared with the prior art which mostly focuses on the testing conditions of single-phase samples, the problem of difficult testing of multiphase and multicomponent samples is solved.

[0021] 2. By winding the independent heating wire assembly, the surface of the sample cell is heated more uniformly, reducing the influence of temperature gradient on the test results; and the separate temperature control of the heating wire assemblies on both sides of the sample cell can effectively make up for the heat loss caused by heat exchange. Compared with the inherent defect of inaccurate temperature control in the prior art, the problem of uneven temperature field distribution inside the sample cell is effectively solved.

[0022] 3. By adding a gas pipeline at the outlet of the sample cell, the present invention effectively realizes the separation of different phase media in the thermal stability test of multiphase and multicomponent samples, facilitating the component analysis of the subsequent reaction products; and the newly added gas pipeline system can introduce other media during the reaction through the gas interface, facilitating the exploration of its influence mechanism on the thermal reaction of the sample. Compared with the inherent defect of difficult collection of reaction gases in the prior art, the addition of the gas pipeline system solves the problem of uncontrollable introduction and collection of gas components.

[0023] 4. The present invention provides a complete data support and safety guarantee for the entire adiabatic calorimetry test process of multi-phase and multi-component samples by adding an intelligent measurement and control system to monitor key parameters such as temperature and pressure on both sides of the dumbbell-shaped sample cell structure in real time, as well as the parameter differences between different phase media during the reaction process, ensuring the efficient and stable operation of the adiabatic calorimetry test. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] For ease of explanation, the present invention will be described in detail with reference to the following drawings.

[0025] Figure 1 Schematic diagram of the dumbbell-shaped sample cell structure of the adiabatic calorimetry system according to an embodiment of the present invention;

[0026] Figure 2 Schematic diagram of the gas pipeline of the adiabatic calorimetry system according to an embodiment of the present invention;

[0027] Figure 3 Schematic diagram of temperature control of the independent heating wire assembly of the adiabatic calorimetry system according to an embodiment of the present invention;

[0028] Figure 4 Schematic diagram of the adiabatic calorimetry measurement and control system according to an embodiment of the present invention;

[0029] Figure 5 Schematic diagram of the temperature of the left sample cell during the thermal runaway of lithium iron phosphate according to an embodiment of the present invention;

[0030] Figure 6 Schematic diagram of the pressure of the right sample cell during the thermal runaway of lithium iron phosphate according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0032] The following further details the adiabatic calorimetry sample cell structure and test method for multi-phase and multi-component samples provided by the present invention with reference to the drawings and specific implementation schemes.

[0033] Please refer to Figure 1 , an adiabatic calorimetry sample cell structure for multi-phase and multi-component samples is proposed in an embodiment of the present application, including a dumbbell-shaped sample cell structure, an independent heating wire assembly, a gas pipeline system, and an intelligent measurement and control system.

[0034] The dumbbell-shaped sample cell is the core structure. The independent heating wire assembly is closely wound around the outer sphere of the dumbbell-shaped sample cell. The gas pipeline system is connected to the dumbbell-shaped sample cell. The intelligent measurement and control system is used for the test and regulation of the overall calorimetry structure.

[0035] Among them, the entire dumbbell-shaped sample cell is located inside the adiabatic calorimetry cavity, and its structural form is a double-sphere dumbbell or a double-cylinder dumbbell. The overall structure of the dumbbell-shaped sample cell includes: externally embedded independent heating wire assemblies 1 and 5, titanium alloy sample cells 2 and 6 with the same structural dimensions; cavity structures 3 and 7 for containing samples in different phases, and connecting pipelines 4, etc. The two independent sample cells can achieve adiabatic analysis of different phase compositions of the samples. One side is used for analyzing gas-liquid or gas-solid phases, and the other side is used for the collection and test of gas phases. This unique structural design expands the internal space of the sample cell and enables the collaborative reaction study of multi-phase and multi-component samples and other introduced substances.

[0036] Among them, the independent heating wire assembly is located on the outer surface of the sphere or cylinder of the dumbbell-shaped sample cell. The heating wire of the spherical sample cell is wound based on a specific spiral trajectory. The heating wire starts from one end of the spiral and winds upward along the outer surface of the sphere at a constant pitch until the entire sphere surface is covered; the heating wire of the cylindrical sample cell is wound around the cylinder surface in an equidistant spiral manner to ensure that the distance between any two adjacent turns of the heating wire is constant in the axial direction of the sample cell. The independent heating wire assembly is used to separately heat and control the temperature of both sides of the dumbbell-shaped sample cell structure, and compensates for heat loss caused by heat conduction in real time; its unique winding method ensures the uniform heating of the outer surface of the sample cell structure.

[0037] In this embodiment, the heat loss compensation during the reaction process of multi-phase and multi-component samples is realized by externally embedding independent heating wire assemblies 1 and 5. The independent heating wire assemblies 1 and 5 use nickel-chromium alloy heating wires with stable structures and strong corrosion resistance, which greatly extends the service life of the overall structure of the sample cell; the heating wire assemblies are evenly wound on the outer wall of the sample cell, greatly avoiding the risk of local overheating.

[0038] In this embodiment, the reaction space of multi-phase and multi-component samples is effectively expanded by sample cells 2 and 6 with the same structural dimensions. The sample cells 2 and 6 are made of titanium alloy materials with good high-temperature resistance and strong fatigue resistance. The density of titanium alloy is about 4.5 g / cm 3 or so, and the working temperature can reach 600 °C, meeting the test requirements of conventional multi-phase and multi-component samples.

[0039] In this embodiment, the cavity structures 3 and 7 with different phase samples built-in can achieve the separation of different phase samples, facilitating the collection of reactants and the study of the phase interaction mechanism of multi-phase and multi-component samples. The connecting pipeline 4 is made of titanium alloy with the same material as the sample pools 2 and 6, reducing the influence of heat transfer inside the dumbbell-shaped sample pool structure. In addition, when a multi-phase and multi-component sample reacts to generate gas, the connecting pipeline 4 can introduce the gas generated by the reaction in the left sample pool 2 into the right sample pool 6. If the pressure in the right sample pool 6 is higher than a certain safety threshold, the connecting pipeline 4 can balance the internal pressure of the sample pool structure, ensuring the safe progress of the thermal stability test of the multi-phase and multi-component sample.

[0040] Please refer to Figure 2 , in this embodiment, a gas pipeline for testing multi-phase and multi-component samples is proposed based on the dumbbell-shaped sample pool structure. Among them, the overall structure of the gas pipeline includes: a cooling gas cylinder 8, a blowing gas cylinder 9, a gas collection steel cylinder 10, pressure sensors 11 and 12, four-way joints 13 and 14, a pressure relief valve 15, switching gas valves 16, 17, 18 and other parts.

[0041] In this embodiment, the four-way joints 13 and 14 are used to ensure the smooth flow of gas in the entire gas pipeline structure. The four-way joints 13 and 14 belong to a closed structure. The upper end of the joint is connected to a plug or a temperature sensor according to the test requirements; the lower side of the four-way joint is connected to both sides of the dumbbell-shaped sample pool, and the reaction pressures on both sides of the dumbbell-shaped sample pool are monitored in real time by relying on the two pressure sensors 11 and 12.

[0042] Preferably, the left side of the four-way joint 13 is connected to the outside air and the cooling gas cylinder 8 through the pressure relief valve 15 and the switching gas valve 16 respectively. It should be noted that during normal adiabatic calorimetry tests, both the switching gas valve 16 and the pressure relief valve 15 are in the closed state. After the thermal stability test of the multi-phase and multi-component sample is completed, the pressure relief valve 15 is opened and the switching gas valve 16 is closed, and the gas pipeline system is directly connected to the atmospheric environment to achieve the effect of releasing the reaction end pressure; the pressure relief valve 15 is closed and the switching gas valve 16 is opened, and the cooling gas cylinder 8 (the gas inside is usually nitrogen) introduces cooling gas into the gas pipeline to achieve rapid cooling after the reaction ends.

[0043] Preferably, the right side of the four-way joint 14 is connected to the gas collection steel cylinder 10 and the blowing gas cylinder 9 through the switching gas valves 17 and 18 respectively. When it is necessary to analyze the reaction gas production components during the test of the multi-phase and multi-component sample, the switching gas valve 17 is opened and the switching gas valve 18 is closed, and the reaction gas production flows along the gas pipeline to the gas collection steel cylinder 10, so as to achieve the effect of collecting the reaction gas production for analyzing the influence of the remaining gas phase components on the thermal runaway of the existing sample; when it is necessary to study the influence mechanism of the gas phase substance on the existing reaction during the adiabatic calorimetry test of the multi-phase and multi-component sample, the switching gas valve 17 can be closed and the switching gas valve 18 can be opened, and the gas phase substance is blown into the gas pipeline from the blowing gas cylinder 9 and enters the dumbbell-shaped sample pool through the four-way joint 14 to achieve the effect of the gas phase substance intervening in the adiabatic calorimetry reaction.

[0044] Please refer to Figure 3 , in this embodiment, the precise temperature control of the reaction of the multi-phase and multi-component sample is realized by externally embedding the independent heating wire assemblies 1 and 5.

[0045] The temperature control logic of the independent heating wire assembly is as follows:

[0046] (1) Add the multi-phase and multi-component sample to be measured into the left sample cell and initialize the temperature control parameters;

[0047] (2) According to the difference between the preset temperature and the temperature measured by the temperature sensor, the power of the independent heating wire on the outer surface of the left sample cell is fed back in real time; after reaching the step temperature, detect whether the reaction occurs;

[0048] (3) After the reaction occurs, control the independent heating wire on the outer surface of the left sample cell to heat and track the reaction temperature of the sample until the reaction ends.

[0049] (4) The heating wire on the outer surface of the right sample cell controls the temperature to follow the gas phase temperature in the cavity during the whole experiment.

[0050] The specific temperature control steps are as follows: Set initial temperature control parameters such as the starting interval temperature, starting interval temperature rise rate, step size, step constant temperature time, reaction detection threshold, etc. When the sample temperature is lower than the starting interval temperature, the adiabatic calorimeter body heating wire heats the furnace body at the starting interval temperature rise rate, and the difference between the temperature measured by the temperature sensor and the target temperature of the starting interval is used to feed back the output power of the externally embedded heating wire assemblies 1 and 5 in real time; until the temperature measured by the temperature sensor meets the constant temperature condition, the externally embedded heating wire assemblies 1 and 5 control the output to maintain a constant temperature state, and at the same time, the constant temperature flag starts to count; by feeding back the heating rate of the sample in real time, if the heating rate of the sample is higher than the reaction detection threshold, it is judged that the reaction occurs. At this time, control the externally embedded heating wire output to control the temperature to track the sample temperature until the reaction ends. If no reaction is detected within the set constant temperature time of the constant temperature count, calculate the target temperature of the next step. The temperature control logic of each step follows the starting interval step until the adiabatic calorimetry test ends.

[0051] Please refer to Figure 4, in this embodiment, the feedback control of the entire measurement and control system is completed through the cooperation of the furnace heating wire assembly 21, pressure sensors 11, 12, and temperature sensors 19, 20. The specific control logic is as follows: The temperature sensors 19, 20 and pressure sensors 11, 12 respectively monitor the temperature and pressure changes on both sides of the dumbbell-shaped sample cell in real time. When the adiabatic calorimetry test of the multi-phase and multi-component sample starts, the furnace heating wire assembly 21 starts to work first. The heat loss generated during the heating process is compensated by the output of the externally embedded heating wire assemblies 1, 5. The real-time temperature changes measured by the temperature sensors 19, 20 are fed back to the control system, and the feedback output is carried out according to the temperature detection value and the set value, and then the output power of the heating wire is changed to achieve the effect of feedback control; when the real-time pressure values measured by the pressure sensors 11, 12 change, they are correspondingly output to the gas pipeline system to realize the pressure distribution of the entire measurement and control system.

[0052] This embodiment proposes a dumbbell-shaped sample cell structure for multi-phase and multi-component samples and realizes the feedback control of the entire measurement and control system. In addition, this embodiment also proposes a standard test method for multi-phase and multi-component samples, as follows:

[0053] Step 1: Close the pressure relief valve 15, switch gas valves 16, 17, 18 to ensure good airtightness of the entire device.

[0054] Step 2: Load the weighed multi-phase and multi-component sample into the left cavity 3 of the dumbbell-shaped sample cell, open the switch gas valve 17, and keep the switch gas valves 16, 18 and the pressure relief valve 15 closed. The dumbbell-shaped sample cell is fixed on the four-way joints 13, 14 through the ferrule joints.

[0055] Step 3: The measurement and control system sets the adiabatic calorimetry experiment parameters, and the furnace heating wire assembly 21 starts to heat. The temperature sensors 19, 20 detect the temperature inside the dumbbell-shaped sample cell in real time, and change the output power of the externally embedded independent heating wires 1, 5 according to the measured temperature and the set temperature.

[0056] Step 4: When it is detected that the multi-phase and multi-component sample starts to react, the furnace heating wire assembly 21 and the externally embedded independent heating wire assemblies 1, 5 stop active heating, and the output power of the externally embedded heating wires 1, 5 is fed back according to the temperature measured by the temperature sensors 19, 20, and the temperatures on both sides of the dumbbell-shaped sample cell start to be tracked in real time.

[0057] Step 5: The pressure sensors 11, 12 respectively detect the pressure changes on both sides of the dumbbell-shaped sample cell, and the reaction-generated gas sequentially enters the gas collecting bottle 10 through the connecting pipeline 4, the sample cell 6, the four-way joint 14, and the switch gas valve 17.

[0058] Step 6: After the adiabatic calorimetry test of the multi-phase and multi-component sample is completed, close the switch gas valves 16, 17, 18, and open the pressure relief valve 15 to achieve the pressure relief effect.

[0059] Step 7: Close the pressure relief valve 15, the switching gas valves 17 and 18, and open the switching gas valve 16. The cooling gas enters the inside of the dumbbell-shaped sample cell from the cooling gas cylinder 8 via the four-way joint 13 to achieve rapid cooling.

[0060] To verify the above design, the present application further provides the following simulated thermal runaway experiment.

[0061] According to the improved dumbbell-shaped sample cell structure and test method of the present application, a simulation experiment was carried out on the lithium iron phosphate material. The lithium iron phosphate electrolytic material was placed in the left sample cell cavity, and the initial temperature control parameters were set as follows: starting interval temperature 50 °C, starting interval constant temperature time 120 min, stepwise temperature increase step 5 °C, stepwise temperature increase rate 5 °C / min, stepwise constant temperature time 90 min, reaction judgment threshold 0.03 °C / min, reaction end temperature 350 °C, see Figure 5 .

[0062] As Figure 6 shown, the results show that: the initial reaction temperature of the left sample cell is 101.2 °C, the adiabatic temperature rise is 295.4 °C, and the gas generated during the reaction enters the right sample cell through the dumbbell-shaped sample cell structure. The adiabatic pressure rise of the right sample cell is 0.023 Mpa, realizing the different phase separation of the multi-phase and multi-component sample, which is convenient for subsequent analysis of gas components.

[0063] The above is the implementation manner of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, various deformations and improvements can still be made, which should also be regarded as the protection scope of the present invention.

Claims

1. An adiabatic calorimetry sample cell structure for multi-phase and multi-component samples, characterized in that, Including: A sample cell body, which is of dumbbell-shaped structure and includes two independent sample cell parts for separately accommodating samples with different phase compositions; A heating assembly, which includes independent heating wires closely wound around the outside of the sample cell body for separately heating and controlling the temperature of the sample cell to compensate for heat dissipation and ensure uniform heating of the sample cell surface; A gas pipeline system, which is connected to the sample cell body and is used for introducing and collecting gases during the sample reaction process; A measurement and control system, which is used for real-time monitoring of parameters such as temperature and pressure inside the sample cell body and regulating the heating assembly and the gas pipeline system according to the monitoring results.

2. The adiabatic calorimetry sample cell structure for multi-phase and multi-component samples according to claim 1, characterized in that, The structural form of the sample cell body is double-sphere dumbbell-shaped or double-cylinder dumbbell-shaped, and the two independent sample cell parts are respectively used for analyzing gas-liquid or gas-solid phases and for the collection and testing of gas phase.

3. The adiabatic calorimetry sample cell structure for multi-phase and multi-component samples according to claim 2, wherein The independent heating wires are wound around the outer surface of the sphere or cylinder of the sample cell body along a helical trajectory, and starting from one end of the helix, the heating wires are wound upward along the outside of the sphere or cylinder with a constant pitch until the entire surface is covered.

4. The adiabatic calorimetry sample cell structure for multi-phase and multi-component samples according to claim 1, characterized in that, The gas pipeline system includes a pressure relief valve, two four-way joints, multiple on-off gas valves, a gas collection cylinder and a cooling gas cylinder. The pressure relief valve and the on-off gas valves are both connected to the sample cell through the four-way joints and are used for the release of reaction pressure and the introduction of cooling gas.

5. The adiabatic calorimetry sample cell structure for multi-phase and multi-component samples according to claim 4, characterized in that, The measurement and control system includes a temperature sensor and a pressure sensor. The temperature sensor and the pressure sensor are independently connected to the remaining two sides of the four-way joint and are used for real-time monitoring of the temperature and pressure changes on both sides of the sample cell.

6. An adiabatic calorimetry test method for multi-phase and multi-component samples, using the structure described in claim 1, characterized in that, Including the following steps: Step 1. Load a multi-phase and multi-component sample into the left cavity of the dumbbell-shaped sample cell. The dumbbell-shaped sample cell includes two independent sample cell parts for separately accommodating samples with different phase compositions; Step 2. Close the pressure relief valve and the on-off gas valves in the gas pipeline system to ensure good airtightness of the whole device; Step 3. Set the adiabatic calorimetry experiment parameters, start the heating assembly to heat the sample cell, detect the temperature inside the sample cell in real time through the temperature sensor, and adjust the output power of the heating assembly according to the comparison between the measured temperature and the set temperature; Step 4. After detecting that the sample starts to react, stop the active heating, adjust the output power of the heating assembly according to the temperature feedback measured by the temperature sensor, and track the temperature change inside the sample cell in real time; Step 5. Collect the gases generated during the reaction process through the gas pipeline system and monitor the pressure change inside the sample cell through the pressure sensor; Step 6. After the test is completed, release the pressure and rapidly cool down through the gas pipeline system.

7. The adiabatic calorimetry test method for multi-phase and multi-component samples according to claim 6, wherein In Step 3, the adiabatic calorimetry experiment parameters include initial temperature control parameters such as the starting interval temperature, the starting interval temperature rise rate, the step size, the step constant temperature time, and the reaction detection threshold.

8. The adiabatic calorimetry test method for multi-phase and multi-component samples according to claim 6, characterized in that, In Step 4, when it is detected that the sample temperature rise rate is higher than the preset reaction detection threshold, it is determined that the reaction occurs. At this time, control the output power of the heating assembly to track the sample temperature until the reaction ends.

9. The adiabatic calorimetry test method for multi-phase and multi-component samples according to claim 6, characterized in that, In the said step 5, the gas pipeline system includes a pressure relief valve, two four-way joints, multiple switch gas valves, a gas collection cylinder and a cooling gas cylinder. The reaction-generated gas sequentially enters the gas collection cylinder via a connecting pipeline, a sample cell, a four-way joint and a switch gas valve.

10. The adiabatic calorimetry test method for multi-phase and multi-component samples according to claim 9, characterized in that, In the said step 3, the temperature sensor and the pressure sensor are respectively and independently connected to both sides of the four-way joint for real-time monitoring of the temperature and pressure changes on both sides of the sample cell.

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