A method for measuring the physical properties of liquid / solid electrolytes

Abstract

A method for measuring the physical properties of liquid / solid electrolytes, belonging to the field of nonferrous metallurgy, specifically discloses a finite element analysis-assisted thermal analysis method to obtain the thermal conductivity, primary crystallization temperature, electrolyte composition, and latent heat of phase transition of liquid / solid electrolytes. The method includes the following steps: measuring the thermal analysis curve of a liquid molten salt sample during cooling using a sensor; simulating the behavior of the thermal analysis curve using a sensor physical model established by finite element analysis; and comparing and analyzing the numerical thermal analysis curve and the measured thermal analysis curve to obtain the corresponding liquid / solid thermal conductivity, primary crystallization temperature, electrolyte composition, and latent heat of phase transition of the molten salt system. The method described in this invention can rapidly obtain the thermal conductivity, primary crystallization temperature, molten salt composition, and latent heat of phase transition of solid / liquid inorganic salts and multi-component mixtures, enabling online measurement of relevant physical properties of liquid molten salts and solid electrolytes, and possesses practicality and economy.

Description

Technical Field

[0001] This invention belongs to the field of non-ferrous metallurgical technology, specifically relating to a method for measuring the thermal conductivity, primary crystallization temperature, electrolyte composition, and latent heat of phase transition of liquid / solid electrolytes. Background Technology

[0002] In energy, chemical, and metallurgical fields, molten salts and solid electrolytes are widely used in high-temperature reactions, energy storage, and heat and mass transfer. The physical properties of molten salts and solid electrolytes, such as thermal conductivity, primary crystallization temperature, melting point, and latent heat of phase change, are crucial for studying and controlling reaction performance and heat and mass transfer efficiency. For example, in the field of solar power generation, molten salt thermal storage technology has become an important heat storage method. The operating efficiency of molten salt thermal storage systems directly depends on the thermophysical properties of the molten salt. Therefore, accurately measuring these parameters is of great significance for the research and application of molten salt systems and solid electrolytes.

[0003] Currently, obtaining parameters such as thermal conductivity, primary crystallization temperature, molten salt composition, and latent heat of phase change for liquid molten salts and solid electrolytes is mainly achieved through laboratory testing. Traditional laboratory testing methods are lengthy and cumbersome, requiring multiple instruments and methods to obtain the aforementioned physical properties, making them unsuitable for rapid, large-scale, real-time testing in the field. Patent CN110133043A discloses a method for measuring the thermal conductivity of solid materials, which uses laser flash method to obtain sample temperature distribution data and calculates thermal conductivity based on Fourier's law of thermal conductivity using the temperature gradient and spatial distance on the sample surface. This method requires precise experimental setup and instruments to ensure stable heating and temperature measurement, making it difficult to operate. Patent CN108717067A discloses a method for testing the thermal conductivity of phase change energy storage materials, based on the principles of heat conduction and heat flow measurement. By measuring heat flow and temperature changes, and combining the relationship between phase change temperature and thermal conductivity, the thermal conductivity value of the sample at a specific temperature is finally calculated using a formula. This method relies on whether the phase transition temperature and the measured temperature are equal to select the calculation formula. For samples with multiple phase transitions, it may not be able to accurately calculate the thermal conductivity. Patents CN111962101A, CN101871821A, and CN103759835A disclose a method for measuring the primary crystallization temperature of an electrolyte. All three methods determine the primary crystallization temperature of the electrolyte by measuring the heating / cooling curve. However, at higher temperatures, this can damage the test components used, reducing their lifespan and preventing continuous temperature measurement. Patent CN1100807A discloses a method for measuring the molecular ratio of an aluminum electrolyte. This method involves adding a certain amount of sodium fluoride to the electrolyte and then sintering it at high temperature. The electromotive force E of the leaching solution is measured using a fluoride ion-selective electrode, and the C value is obtained by plotting an E-logC standard curve. Finally, the molecular ratio of the electrolyte is calculated according to the formula. This method suffers from problems such as incomplete reaction between sodium fluoride and the aluminum electrolyte, leading to inaccurate analytical results and large errors. Patent CN1100807A discloses an analytical method for the molecular ratio of high-lithium potassium-aluminum electrolytes. The principle is based on the relationship between conductivity and electrolyte concentration. By measuring the conductivity value of the electrolyte solution, the electrolyte concentration is indirectly reflected; that is, the electrolyte composition can be calculated using a formula based on the measured conductivity value and a known temperature value. However, this method only reflects the ion concentration of the electrolyte, and the molecular ratio of high-lithium potassium-aluminum electrolytes is also affected by other factors. Therefore, conductivity only provides an approximate estimation method rather than a precise calculation. Patent CN109540960A discloses a method for measuring the specific heat capacity and latent heat of phase change of a substance. This method is based on the law of conservation of heat and the principle of temperature stability. First, the heat capacity of the calorimeter itself is calculated according to the principle of thermal balance. Then, by measuring the temperature and mass of the test sample and the calorimetric liquid, as well as the melting time of the phase change material, the latent heat of phase change of the solid-liquid phase change substance is calculated. This method requires precise temperature control of the test sample, making it technically challenging.

[0004] None of the technical solutions disclosed above can simultaneously measure the thermal conductivity, primary crystallization temperature, molten salt composition, and latent heat of phase change of liquid molten salt and solid electrolyte online, thus failing to provide quick reference and guidance for the measurement of liquid molten salt and solid electrolyte in actual industrial processes. Summary of the Invention

[0005] In view of the aforementioned shortcomings and deficiencies of the prior art, the purpose of this invention is to provide a method for measuring the physical properties of liquid / solid electrolytes, including thermal conductivity, primary crystallization temperature, electrolyte composition, and latent heat of phase transition. This method can effectively predict the thermal conductivity, primary crystallization temperature, molten salt composition, and latent heat of phase transition of monocomponent and multicomponent molten salts. The detection method of this invention can also perform real-time online measurement of relevant physical properties of pure substances, mixtures, and multi-component mixtures, providing reference and guidance for practical industrial measurements.

[0006] A method for measuring physical properties of liquid / solid electrolytes, said physical properties including thermal conductivity, primary crystallization temperature, electrolyte composition, and latent heat of phase transition, such as... Figure 1 As shown, the specific steps include:

[0007] S1 uses a sensor to measure the thermal analysis curve of a liquid molten salt sample during the cooling process; the sensor uses dual-temperature thermocouples to collect the electrolyte temperature and the metal body temperature respectively, and constructs a molten salt-metal temperature difference time curve.

[0008] S2 uses the finite element method to establish a physical model of the sensor to simulate the behavior of the thermal analysis curve;

[0009] The established physical model is a radiation-conduction-convection coupled heat transfer model, which includes three heat transfer modes: conduction-convection and radiation heat transfer.

[0010] S3 compares and analyzes numerical thermal analysis curves and measured thermal analysis curves to obtain the corresponding liquid / solid thermal conductivity, molten salt primary crystallization temperature, electrolyte composition and latent heat of phase change of the molten salt system.

[0011] The methods for calculating the liquid / solid thermal conductivity and latent heat of phase change in molten salt systems are as follows:

[0012] S3-1 Based on known experimental data or theoretical knowledge, determine the possible range of values ​​for the thermal conductivity and latent heat of phase change of molten salt;

[0013] S3-2 determines the initial values ​​of molten salt thermal conductivity and latent heat of phase change from the possible range of values, and uses them as the initial input values ​​K0 and L0 of the physical model; where K0 is the initial estimated value of molten salt thermal conductivity, W / (m·K); and L0 is the initial estimated value of latent heat of phase change, W / m 3 ;

[0014] The initial value of thermal conductivity is related to the state of the electrolyte and is determined based on the characteristics of the temperature-time curve obtained from step S1. The mathematical model of the relationship between thermal conductivity and temperature is given by formula (1), and the liquid / solid thermal conductivity of the molten salt system at a certain temperature is calculated from this formula and input as an estimated value into the finite element physical model.

[0015]

[0016] In the formula, m and X are model scaling factors, where the value of m is related to the type of crystalline phase in the system, and X is related to the molar volume of atoms in the system; T is the temperature in K; and K is the thermal conductivity to be measured in W / (m·K).

[0017] The initial value of the latent heat of phase change is based on the principle of phase equilibrium, that is, the chemical potentials of the two phases (α and β) are equal at phase equilibrium, and is denoted as μ. α (T,P)=μ β (T,P) yields L=T(s) β -s α ) = h β -h α =Δh, the difference in enthalpy at different temperatures is used as the estimated value of the latent heat of phase change of the molten salt system and input into the model. The lowercase s and h represent molar entropy and molar enthalpy, respectively. P represents pressure, T represents temperature, and L represents the estimated value of the latent heat of phase change of the molten salt system.

[0018] S3-3 uses a finite element model to calculate the temperature-time relationship curve of the electrolyte sample and records the temperature information, denoted as Tc:

[0019] S3-4 uses a sensor to record the temperature information of the electrolyte sample during the cooling process, denoted as Tm;

[0020] S3-5 Based on the measured value Tm and the calculated value Tc, establish the inference function ΔT = 100% * (Tm - Tc) / Tm;

[0021] S3-6 updates the thermal conductivity and latent heat of phase change values ​​based on the inference function results, and checks whether the numerical thermal analysis curve and the measured thermal analysis curve fit each other. If the fitting condition is met, the thermal conductivity and latent heat of phase change values ​​are output; otherwise, the thermal conductivity and latent heat of phase change are continued to be calculated.

[0022] S3-7 outputs the final thermal conductivity and latent heat of phase change.

[0023] The thermal conductivity is updated by adjusting the X and m values ​​in the thermal conductivity equation. The fitting criteria are as follows: within the target study period, the model scaling coefficients X and m are repeatedly adjusted until the maximum relative error of the temperature data Tc and Tm of the numerical thermal analysis curve and the measured thermal analysis curve is ≤5%, that is, the maximum value of the inference function is ≤5%.

[0024] The calculation method also includes:

[0025] The initial crystallization temperature is obtained from the numerical thermal analysis curve that meets the fitting conditions. That is, when the molten salt temperature reaches the initial crystallization temperature, the slope of the numerical thermal analysis curve will change, and a plateau will appear on the simulation curve. The temperature corresponding to the plateau is the initial crystallization temperature.

[0026] The electrolyte composition is estimated by using the relationship between the latent heat value and composition of the simulated output, and then calculating it using a specific formula that matches the electrolyte to be tested.

[0027] The reactions involve the following formulas: AlF3 + NaF = Na3AlF6 ①, AlF3 + Na3AlF6 = Na5Al3F 14 ②

[0028] The mass of cryolite formed at various molecular ratios is calculated according to formula ①, and the theoretical value is defined as follows: M t =M i ÷M1, where M i M1 represents the mass of cryolite under the corresponding molecular ratio condition, where M1 is the mass of cryolite when the molecular ratio is 3.0.

[0029] The formula for the simulated value is: L t =L i ÷L1, where L i M1 represents the latent heat of the first phase change under the corresponding molecular ratio condition, and M1 represents the latent heat of the first phase change when the molecular ratio is 3.0.

[0030] Furthermore, the molten salt and solid electrolyte are one or more of nitrates, carbonates, halide salts, acetates, phosphates, and sulfates.

[0031] Furthermore, the thermocouple used in the sensor is a type K nickel-chromium / nickel-silicon thermocouple or a type S platinum-rhodium / platinum thermocouple.

[0032] Furthermore, the software used in the finite element method is selected from Fluent, COMSOL, and Multiphysics.

[0033] Furthermore, the proportionality coefficients X and m that satisfy the conditions are not unique. The key factors affecting the simulation curve are the thermal conductivity and latent heat of phase change of the material. The thermal conductivity and latent heat of phase change values ​​of the material in the model are input into the model using a trial-and-error method, while the derived thermal conductivity value is calculated through the thermal conductivity formula. Specifically, the values ​​of X and m in the formula are first adjusted to obtain the thermal conductivity value. At this time, X and m can take any value. Then, the thermal conductivity value calculated through the values ​​of X and m is input into the model for calculation to obtain the simulation curve. The simulation curve is compared with the experimental curve. If the maximum value of ΔT is ≤5%, then the X and m values ​​are determined to be valid. There is more than one X and m value that satisfies this condition.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The temperature field distribution inside the molten salt sample is simulated by the finite element method. The influence of the non-uniformity and complex geometry of the molten salt sample on heat transfer is considered, which improves the accuracy and reliability of the measurement results.

[0036] (2) It is applicable to various molten salt samples and can be used to detect the thermal behavior of pure substances, mixtures and multi-component mixtures, and has a wide range of applications;

[0037] (3) It can perform online measurements and monitor the physical properties of liquid molten salt and solid electrolyte in real time. It is simple to operate, practical and economical, and provides reference and guidance for actual industrial measurements. Attached Figure Description

[0038] Figure 1 This is a flowchart illustrating the method for measuring the thermal conductivity and latent heat of phase change of liquid / solid electrolytes according to the present invention.

[0039] Figure 2 This is a cross-sectional view of the overall structure of the thermal analysis sensor used in this invention;

[0040] In the diagram: 1-molten salt sampling cup; 2-solid metal column; 3-reference temperature coupler; 4-molten salt measuring coupler; 5-metal connecting ring; 6-protective sleeve; 7-compensating wire; 8-data acquisition and analysis system;

[0041] Figure 3 This is a thermal analysis curve of NaCl in Example 1;

[0042] Figure 4 This is a numerical graph of the inference function of NaCl in Example 1;

[0043] Figure 5 This is the thermal analysis experimental curve of 3NaF-AlF3 in Example 2;

[0044] Figure 6This is a numerical graph of the inference function of 3NaF-AlF3 in Example 2;

[0045] Figure 7 This is the thermal analysis experimental curve of 2.4NaF-AlF3 in Example 3;

[0046] Figure 8 This is a numerical plot of the inference function for 2.4NaF-AlF3 in Example 3;

[0047] Figure 9 This is the thermal analysis experimental curve of 2.7NaF-AlF3 in Example 4;

[0048] Figure 10 This is a numerical plot of the inference function of 2.7NaF-AlF3 in Example 4. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0050] Example 1

[0051] A method for measuring the thermal conductivity of liquid / solid electrolytes in a NaCl molten salt system, specifically including the following steps:

[0052] (1) Place 700g of NaCl sample in a graphite crucible and heat it to 1100℃ in a resistance furnace;

[0053] (2) A thermal analysis sensor was used to record the temperature change of the NaCl molten salt sample as it cooled to 277℃. The temperature information was recorded as Tm, and a corresponding temperature-time curve was established. A K-type thermocouple was used to record the temperature data for the sensor probe. The thermal analysis experimental curve is shown below. Figure 3 As shown; the thermal analysis sensor used is as follows Figure 2 As shown;

[0054] (3) Using finite element software, input the physical parameters of molten salt into the finite element model to establish a sodium chloride 3D model. Set the initial temperature of the air domain of the model to 27℃, and the initial temperature of the sensor domain and the molten salt domain to 1100℃.

[0055] (4) Based on known experimental data or theoretical knowledge, determine the possible ranges of NaCl thermal conductivity and latent heat of phase change, and select 3.9111 W / (m·K) and 490000 J·kg from the possible ranges. -1 As the initial input values ​​for the model;

[0056] (5) Calculate the temperature-time relationship curve of the liquid molten salt sample in the model, record the temperature information, and denote it as Tc;

[0057] (6) Based on the measured value Tm and the calculated value Tc, establish the inference input function ΔT = 100% * (Tm - Tc) / Tm;

[0058] (7) Update the thermal conductivity and latent heat of phase change based on the inferred input function results, and determine that m is 1, X1 is 1600, and X2 is 635 (X1 and X2 represent the thermal conductivity K and 1 / T in the molten state and crystalline state, respectively). m The coefficients between them), and the values ​​of the inferred function are as follows. Figure 4 As shown, the maximum value of ΔT at this time is 3.9%, which is less than the 5% effectiveness criterion. The thermal conductivity and latent heat of phase change values ​​can be output.

[0059] (8) Summarize the output thermal conductivity values ​​based on the liquid and solid states to obtain the thermal conductivity expressions for the NaCl system in the crystalline and molten states:

[0060] Crystalline state: K2 = 635T -1 836K-1073K(1)

[0061] Molten state: K1 = 1600T -1 1074K-1400K(2)

[0062] The latent heat of phase change during the solid-liquid conversion of sodium chloride was also found to be 490736.2 J·kg⁻¹. -1 The primary crystallization temperature is 800.1℃.

[0063] Example 2

[0064] The liquid / solid thermal conductivity, primary crystallization temperature, and latent heat of phase transition of the binary NaF-AlF3 molten salt system were measured using the method described in Example 1, wherein the molar ratio of NaF to AlF3 was 3, denoted as 3NaF-AlF3. The method used differs from that in Example 1 in that:

[0065] The 3NaF-AlF3 molten salt system undergoes two phase transitions during cooling, as shown in the experimental curves based on thermal analysis. Figure 5 As shown, the thermal analysis curve can be divided into three segments, and it can be determined that the model of this system has two latent heat sources for phase change. The formula... The value of m in the equation is between 0.5 and 1. Since the thermal analysis experimental curve of the 3NaF-AlF3 molten salt system has three temperature ranges, the corresponding formula... There are three X values, denoted as X1, X2, and X3 respectively (in the NaF-AlF3 system, X1, X2, and X3 represent the thermal conductivity K and 1 / T in the temperature range above the liquidus temperature, between the liquidus temperature and 563℃ (836K), and below 563℃ (836K). m The three proportionality coefficients (between 95, 100, and 95) are used to infer the values ​​of the function when m is 2 / 3. Figure 6 As shown, the maximum absolute value of the inferred function is 2.58%, thus yielding the thermal conductivity expressions for the 3NaF-AlF3 electrolyte system at various temperature ranges:

[0066] Below 563℃: K3 = 95T -3 / 2 300K-835K(1)

[0067] Between the liquidus temperature and 563℃: K2 = 100T -3 / 2 836K-1282K(2)

[0068] Above the liquidus temperature: K1 = 95T -3 / 2 1283K-1400K(3)

[0069] The latent heat of phase change is 532349.6 J·kg. -1 45041.4 J·kg -1 The primary crystallization temperature is 999.3℃.

[0070] Example 3

[0071] The liquid / solid thermal conductivity, primary crystallization temperature, molten salt composition, and latent heat of phase transition of the binary NaF-AlF3 molten salt system were measured using the method described in Example 2, wherein the molar ratio of NaF to AlF3 was 2.4, denoted as 2.4NaF-AlF3. The experimental curves based on thermal analysis are shown below. Figure 7 As shown, the number of X values ​​present in the relationship between the thermal conductivity and temperature of this system is 3, denoted as X1, X2, and X3. Furthermore, this system has three phase change heat source terms. When the values ​​of X1, X2, and X3 are 90, 85, and 80 respectively, and m is 2 / 3, the values ​​of the inference function are as follows: Figure 8 As shown, the maximum absolute value of the inferred function is 3.28%, thus yielding the thermal conductivity expressions for the 2.4NaF-AlF3 molten salt system at various temperature ranges:

[0072] K1 = 90T -3 / 2 300 K-835 K (1)

[0073] K2 = 85T -3 / 2 836 K-1282 K (2)

[0074] K3 = 80T -3 / 2 1283 K-1400 K (3)

[0075] The latent heat of phase change is 332720.1 J·kg. -1 31145.2 J·kg -1 45041.4 J·kg -1 The initial crystallization temperature is 990.6℃. The ratio of the latent heat of the first phase change in this embodiment to that in Example 2 is 0.625. This value is close to the theoretical value of an electrolyte with a NaF / AlF3 molar ratio of 2.5. Therefore, the analytical value of the molar ratio of NaF to AlF3 in this electrolyte is 2.5, which is close to the formulation value of 2.4, meeting the industrial requirements for the error of electrolyte molecular ratio.

[0076] The theoretical value is calculated using the formula: M t =M i ÷M1

[0077] Among them, M i M1 represents the mass of cryolite under the corresponding molecular ratio condition, where M1 is the mass of cryolite when the molecular ratio is 3.0.

[0078] The formula for the simulated value is: L t =L i ÷L1 where, L i L1 represents the latent heat of the first phase change under the corresponding molecular ratio condition, and L2 represents the latent heat of the first phase change when the molecular ratio is 3.0.

[0079] Example 4

[0080] The liquid / solid thermal conductivity, primary crystallization temperature, molten salt composition, and latent heat of phase transition of the binary NaF-AlF3 molten salt system were measured using the method described in Example 2, where the molar ratio of NaF to AlF3 was 2.7, denoted as 2.7NaF-AlF3. The difference from Example 2 is that an S-type thermocouple was used to collect temperature data. The thermal analysis experimental curves are shown below. Figure 9 As shown, the number of X values ​​present in the relationship between the thermal conductivity and temperature of this system is 3, denoted as X1, X2, and X3 respectively. Furthermore, this system has three phase change heat sources. When X1, X2, and X3 take values ​​of 93, 93, and 90 respectively, and m takes a value of 2 / 3, the values ​​of the inference function are as follows. Figure 10 As shown, the maximum absolute value of the inferred function is 2.70%, thus yielding the thermal conductivity expressions for the 2.7NaF-AlF3 molten salt system across various temperature ranges:

[0081] K1 = 93T -3 / 2 300 K-835 K (1)

[0082] K2 = 93T -3 / 2 836 K-1282 K (2)

[0083] K3 = 90T -3 / 2 1283 K-1400 K (3)

[0084] The latent heat of phase change is 438947.8 J·kg. -1 93435.6 J·kg -1 45041.4 J·kg -1 The initial crystallization temperature is 996.4℃. The ratio of the latent heat of the first phase change in this embodiment to that in Example 2 is 0.824. This value is close to the theoretical value of the electrolyte with a NaF / AlF3 molar ratio of 2.76. Therefore, the analytical value of the molar ratio of NaF to AlF3 in this electrolyte is 2.76, which is close to the prepared value of 2.7, meeting the industrial requirements for the error of the electrolyte molecular ratio.

[0085] The above embodiments should be understood as being used only to illustrate the present invention more clearly, and not to limit the scope of the present invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art fall within the scope defined by the appended claims.

Claims

1. A method of measuring a liquid / solid electrolyte physical property parameter, characterized by, The physical properties include thermal conductivity, primary crystallization temperature, electrolyte composition, and latent heat of phase transition, and include the following steps: S1 uses a sensor to measure the thermal analysis curve of a liquid molten salt sample during the cooling process; the sensor uses dual-temperature thermocouples to collect the electrolyte temperature and the metal body temperature respectively, and constructs a molten salt-metal temperature difference time curve. S2 uses the finite element method to establish a physical model of the sensor to simulate the behavior of the thermal analysis curve; The established physical model is a radiation-conduction-convection coupled heat transfer model, which includes three heat transfer modes: conduction-convection and radiation heat transfer. S3 compares and contrasts numerical thermal analysis curves with measured thermal analysis curves to obtain the corresponding liquid / solid thermal conductivity, primary crystallization temperature, electrolyte composition, and latent heat of phase transition for the molten salt system; among these, thermal conductivity is determined by the thermal conductivity-temperature function. The proportionality coefficients m and X are obtained in the model. m and X are the proportionality coefficients. The value of m is related to the type of crystalline phase in the system, and X is related to the atomic molar volume of the system. T is the temperature in K, and K is the thermal conductivity to be measured in W / (m·K). By adjusting the values ​​of X and m, the maximum relative error of the temperature data Tc and Tm between the numerical thermal analysis curve and the measured thermal analysis curve is ≤5%. The latent heat of phase change in electrolytes is obtained based on the correlation between the temperature range of the latent heat peak of phase change in the thermal analysis curve, the heat release time, and the latent heat of phase change in the electrolyte. First, the latent heat release time of the phase change process is obtained through the measured thermal analysis curve. Then, the latent heat value of the phase change is estimated. Next, the thermal analysis curve of the sensor is simulated using a finite element physical model. The effectiveness of the estimated latent heat of phase change is determined by comparing the fitting degree between the simulated curve and the measured curve.

2. The method for measuring the physical properties of liquid / solid electrolytes according to claim 1, characterized in that, The liquid molten salt sample mentioned in step S1 is one or more of nitrates, carbonates, halide salts, acetates, phosphates and sulfates.

3. The method for measuring the physical properties of liquid / solid electrolytes according to claim 1, characterized in that, The thermocouple used in the sensor described in step S1 is a type K nickel-chromium-nickel-silicon thermocouple or a type S platinum-rhodium-platinum thermocouple.

4. The method for measuring the physical properties of liquid / solid electrolytes according to claim 1, characterized in that, In step S3, the m and X values ​​in the function are first estimated, and then the thermal analysis curve of the sensor is simulated using a finite element physical model. The effectiveness of the estimated m and X values ​​is determined by comparing the fitting degree between the simulated curve and the measured curve.

5. The method for measuring the physical properties of liquid / solid electrolytes according to claim 1, characterized in that, The primary crystallization temperature mentioned in step S3 is estimated by the measured thermal analysis curve. Then, the thermal analysis curve of the sensor is simulated using a finite element physical model. The effectiveness of the estimated primary crystallization temperature is determined by comparing the fitting degree between the simulated curve and the measured curve.

6. The method for measuring the physical properties of liquid / solid electrolytes according to claim 1, characterized in that, In step S3, the electrolyte composition is determined by the relationship between the latent heat of phase change and the electrolyte composition.

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