Quasi-solid-state thermoelectric heating device performance parameter measuring device

Abstract

The utility model belongs to the technical field of thermoelectric performance testing, and particularly relates to a quasi-solid-state thermoelectric heating device performance parameter measuring device which comprises a pair of TEC refrigeration pieces and a circulating water heat exchanger which are arranged in parallel, the heating face of one TEC refrigeration piece faces upwards, and the cooling face of the other TEC refrigeration piece faces upwards; the bottom of the TEC refrigeration sheet is detachably connected to the circulating water heat exchanger; the circulating water heat exchanger is connected with a constant-temperature circulating water bath for providing constant-temperature circulating water; the pair of TEC refrigeration sheets is electrically connected with a direct-current constant-voltage adjustable power supply; the TEC is further electrically connected with a measuring circuit used for measuring performance parameters of the quasi-solid-state thermoelectric heating device. According to the application, a constant-temperature environment can be provided for the quasi-solid sample to be measured, the cold end and the hot end of the TEC refrigeration sheet are freely switched, the device is simple in structure, various required parameters such as voltage, current, power and the like can be measured at high precision, environment temperature control equipment with a complex structure does not need to be additionally arranged, the cost is low, all devices are convenient to replace, and good practicability is achieved.

Description

Technical Field

[0001] The present application belongs to the technical field of thermoelectric performance testing, and specifically relates to a performance parameter measurement device for a quasi-solid-state thermoelectric heating device. Background Art

[0002] The energy shortage problem has become a global concern. In addition to using clean energy such as solar energy, tidal energy, and wind energy as a substitute for fossil fuels, the recovery of waste heat has also become a topic of concern. A large amount of low-grade thermal energy (<200°C), such as human body temperature, industrial waste heat, geothermal heat, etc., is directly dissipated in the environment and cannot be effectively utilized. Using thermoelectric technology to convert this thermal energy into electrical energy is the most direct and feasible method, but traditional semiconductor-based thermoelectric materials are difficult to be commercially applied due to their low Seebeck coefficient (usually 0.01-0.1mV / K), mechanical brittleness, difficulty in synthesis, and high price.

[0003] Recently, the emergence of quasi-solid-state thermoelectric materials based on gel materials has solved these problems. Quasi-solid-state thermoelectric devices fix the electrolyte in the gel material and convert thermal energy into electrical energy based on the Soret effect (ion heat transport) or the thermoelectric effect (temperature-sensitive redox reaction). The Seebeck coefficient is 1-2 orders of magnitude higher than that of traditional semiconductor-based thermoelectric materials (usually >1mV / K), and has the advantages of flexibility, low cost and easy availability. For quasi-solid-state thermoelectric devices, the most important performance parameters are thermal voltage (Seebeck coefficient) and output power. These two parameters directly determine the performance of quasi-solid-state thermoelectric devices, so the measurement method of Seebeck coefficient and power is particularly important in the device development process. The measurement principle of Seebeck coefficient is to apply a temperature difference between two electrodes and measure it by static method or quasi-static method; thermal power is to apply loads of different sizes under a fixed temperature difference, measure the steady-state current and voltage, and calculate it by P=IV. The commonly used measurement equipment is cumbersome and costly, so a simple and low-cost method is needed to measure the performance of quasi-solid-state thermoelectric materials.

[0004] In summary, the measurement principle is that the measurement of the performance of quasi-solid-state thermoelectric materials requires precise control of the temperature of the two electrodes at the cold end and the hot end of the object to be measured to provide the temperature difference required for the measurement, and the ambient temperature needs to remain stable. Heaters and coolers usually use semiconductor refrigeration chips (TECs) because TECs can achieve reversible heating and cooling by adjusting the positive and negative poles. Existing thermoelectric measurement devices almost all use PID temperature controllers to control the temperature difference between the two ends. Although this device achieves precise temperature difference control, its complex structure makes it extremely expensive. Such as Bin Chen, Xu Zhang, Jing Yang, Jiansong Feng, and Taihong Wang. Giant Negative Thermopower Enabled by Bidirectionally Anchored Cations in Multifunctional Polymers. ACS Applied Materials & Interfaces 2023 15 (20), 24483-24493, and Wang S., Li Y., Yu M. et al. High-performance cryo-temperature ionic thermoelectric liquid cell developed through a eutectic solvent strategy. Nat Commun 15, 1172 (2024) used PID temperature control devices of model TCM-X107 and TCM-M207 respectively. In addition, traditional measuring equipment cannot control the temperature of the measuring environment, which requires the support of additional environmental control equipment.

[0005] Therefore, a low-cost device is needed that can achieve precise temperature control at both ends of the test bench and provide a constant temperature environment for the measured samples. Utility Model Content

[0006] Existing thermoelectric heating devices mainly use PID temperature control devices to linearly control the temperature of semiconductor refrigeration plates (TEC) at the cold end and the hot end to produce a temperature difference. Although this method can effectively keep the two ends at the same temperature, the PID temperature control device is complex and expensive, which limits its application. In addition, different ambient temperatures are generally required during experimental testing, and the additional environmental control system increases the cost of the entire set of equipment. Therefore, a low-cost device is needed that can achieve precise temperature control at both ends of the test bench and provide a constant temperature environment for measuring samples. In order to solve the above technical problems, the present application provides a quasi-solid-state thermoelectric heating device performance parameter measurement device that can provide a constant temperature environment, free switching between cold and hot ends, a simple device structure, and high-precision measurement of various required parameters such as voltage, current, and power.

[0007] The present application provides a device for measuring the performance parameters of a quasi-solid-state thermoelectric heating device using the following technical solution:

[0008] A device for measuring the performance parameters of a quasi-solid-state thermoelectric heating device comprises a pair of TEC cooling sheets and a circulating water heat exchanger arranged in parallel, wherein a heating surface of one TEC cooling sheet faces upward, and a cooling surface of the other TEC cooling sheet faces upward; the bottom of the TEC cooling sheet is detachably connected to the circulating water heat exchanger; the circulating water heat exchanger is connected to a constant temperature circulating water bath for providing constant temperature circulating water; a pair of TEC cooling sheets are electrically connected to a direct current constant voltage adjustable power supply; and the TEC is also electrically connected to a measuring circuit for measuring the performance parameters of the quasi-solid-state thermoelectric heating device.

[0009] In a specific implementation manner, the distance between two TEC cooling sheets is 3-5 cm.

[0010] In a specific embodiment, the bottoms of a pair of TEC cooling sheets are coated with thermal grease, and the TEC cooling sheets are adsorbed on the circulating water heat exchanger through the thermal grease.

[0011] In a specific embodiment, the device further comprises a heat conductive support member, wherein the heat conductive support member is placed between a pair of TEC cooling fins, and a bottom of the heat conductive support member is in contact with the circulating water heat exchanger.

[0012] In a specific embodiment, the thermally conductive support member includes a thermally conductive filled copper block.

[0013] In a specific feasible implementation scheme, the measurement circuit includes an electrical parameter measurement circuit and a surface temperature difference measurement circuit; the surface temperature difference measurement circuit includes a pair of temperature probes, and the electrical parameter measurement circuit includes a pair of measurement electrodes; both the temperature probes and the measurement electrodes pass through the quasi-solid sample to be measured, and respectively abut against a pair of TEC cooling plates in one-to-one correspondence; the spacing between the temperature probe and the measurement electrode located on the same TEC cooling plate is ≤5mm.

[0014] In a specific embodiment, the temperature probe comprises a thermocouple or a thermal resistance probe, and the measuring electrode comprises a platinum electrode.

[0015] In a specific implementation scheme, the electrical parameter measurement circuit includes a voltage measurement circuit and a current measurement circuit, which are connected in parallel; the voltage measurement circuit includes a voltage measurement device, and the current measurement circuit includes a current measurement device and a variable resistor connected in series.

[0016] The present application includes at least one of the following beneficial technical effects: the present application uses a pair of TEC refrigeration plates, in conjunction with a circulating water heat exchanger and a measuring circuit, to provide a constant temperature environment for the quasi-solid sample to be tested, and the hot and cold ends of the TEC refrigeration plates can be switched freely. The device has a simple structure and can measure various required parameters such as voltage, current, power, etc. with high precision. There is no need to set up additional complex ambient temperature control equipment, the cost is low, and the components are easy to replace, and it has good practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a line graph of the Seebeck coefficient of a quasi-solid-state thermal battery based on potassium ferrocyanide / potassium ferrocyanide measured using the device of the present application.

[0018] Figure 2 It is a line graph of the Seebeck coefficient of the quasi-solid-state thermal battery based on ferric chloride / ferrous chloride measured by using the device of the present application.

[0019] Figure 3 The voltage-current curve and power curve (ΔT=40K) of a quasi-solid-state thermal battery based on potassium ferrocyanide / potassium ferrocyanide measured using the device of the present application.

[0020] Figure 4 The voltage-current curve and power curve (ΔT=40K) of the quasi-solid-state thermal battery based on ferric chloride / ferrous chloride measured by the device of the present application.

[0021] Figure 5 It is a connection schematic diagram along the top view of a quasi-solid-state thermoelectric heating device performance parameter measurement device provided by the present application.

[0022] Figure 6 This is a schematic diagram of the main viewing direction connection of a quasi-solid-state thermoelectric heating device performance parameter measurement device provided by the present application.

[0023] Explanation of the reference numerals: 1. Placement area; 2. Voltage measuring device; 3. DC constant voltage adjustable power supply; 4. Super constant temperature circulating water bath; 5. Surface temperature difference measuring device; 6. Current measuring device; 7. Rheostat; 8. Circulating water heat exchanger; 9. TEC cooling plate; 10. Quasi-solid sample; 11. Thermal conductive filling copper block; 12. Pipeline. DETAILED DESCRIPTION

[0024] The following is combined with Figure 1-6 This application is described in further detail.

[0025] The present application embodiment discloses a device for measuring performance parameters of a quasi-solid-state thermoelectric heating device, such as Figure 5 and Figure 6 As shown, the device includes a pair of TEC cooling sheets 9, a voltage measuring device 2, a DC constant voltage adjustable power supply 3, a super constant temperature circulating water bath 4, a surface temperature difference measuring device 5, a current measuring device 6, a rheostat 7, a pair of temperature probes, a pair of measuring electrodes, a circulating water heat exchanger 8, and a thermally conductive filling copper block 11.

[0026] The TEC cooling sheet 9 includes two sides, one side is a cooling side and the other side is a heating side. The cooling side of one TEC cooling sheet 9 faces upwards; the heating side of the other TEC cooling sheet 9 faces upwards. Then, the two TEC cooling sheets 9 are placed on the circulating water heat exchanger 8 in the above manner using a detachable fixing method, providing an adjustable positive and negative temperature difference for the quasi-solid sample 10 placed thereon. In this embodiment, the TEC cooling sheet 9 is coated with thermal conductive silicone grease, and no additional fixing method is required. The TEC cooling sheet 9 is only adsorbed on the circulating water heat exchanger 8 using adsorption force. This part of the design is to facilitate the later replacement of TEC cooling sheets 9 of different powers to meet the measurement requirements of different samples.

[0027] Two TEC cooling sheets 9 are placed in parallel with a spacing of 3-5 cm. The spacing in the middle is used to place a heat-conducting copper block 11 of suitable size. The top of the heat-conducting copper block 11 is flush with the two TEC cooling sheets 9, and is used to support the quasi-solid sample 10 to be tested from the middle. The top of the two TEC cooling sheets 9 and the top of the heat-conducting copper block 11 together form a placement area 1. When the device is used, the quasi-solid sample 10 to be tested is laid flat on the placement area 1. It should be noted that the heat-conducting copper block 11 is only a preferred example implementation in this embodiment. Any structure in the prior art that can play a supporting role and a heat-conducting role at the same time and does not affect the normal operation of the device can replace the heat-conducting copper block 11 here.

[0028] The circulating water heat exchanger 8 is externally connected to the super constant temperature circulating water bath 4 through the pipeline 12, that is, the super constant temperature circulating water bath 4 is used to provide hot water to the circulating water heat exchanger 8 to keep its heat constant. The circulating water heat exchanger 8 and the super constant temperature circulating water bath 4 cooperate to not only dissipate heat for the TEC cooling sheet 9, but also achieve the purpose of controlling the ambient temperature by controlling the water temperature, without the need for additional complex temperature control equipment, thus reducing costs.

[0029] The DC constant voltage adjustable power supply 3 is electrically connected to the two TEC cooling plates 9 and is used to supply power to the TEC cooling plates 9 .

[0030] A pair of temperature probes are respectively in contact with the two TEC cooling sheets 9, and the temperature probes are electrically connected to the surface temperature difference measuring device 5. The temperature difference of the top surfaces of the two TEC cooling sheets 9 is measured by the surface temperature difference measuring device 5 and the two temperature probes. The temperature probes can be thermocouples or thermal resistors.

[0031] A pair of measuring electrodes are inserted into the quasi-solid sample 10 and abut against the top surface of the TEC cooling sheet 9. The measuring electrodes are connected to the measuring circuit to measure the current and voltage of the quasi-solid sample 10 under different loads. Platinum electrodes can be used as measuring electrodes. The temperature probe and the measuring electrodes are both placed on the surface of the TEC cooling sheet 9. To avoid measurement errors, the positions of the measuring electrodes of the temperature probe should be as close as possible, preferably with a spacing of ≤5mm.

[0032] The measurement circuit includes two circuits connected in parallel, one of which is provided with a voltage measuring device 2 for measuring the voltage of the quasi-solid sample 10 under different loads, and the other circuit is connected in series with a variable resistor 7 and a current measuring device 6 for measuring the current intensity of the quasi-solid sample 10 under different loads. When the variable resistor 7 is disconnected and there is no load, the measurement data of the voltage measuring device 2 is the open circuit voltage. The slope of the temperature difference-voltage curve ( Figure 1 ), the Seebeck coefficient can be obtained. When the variable resistor 7 is connected, the variable resistor 7 is adjusted to apply different loads, and the voltage and current under different loads are recorded to obtain the voltage-current curve. The power curve can be calculated using the formula P=IV, such as Figure 3 and Figure 4 shown.

[0033] The model of the TEC cooling plate 9 of the present application is Jinghong Thermoelectric TEC1-12706; the model of the circulating water radiator is Shenzhen Taier Electronics 40*120mm; the model of the constant voltage DC adjustable power supply is Maisheng MS305DS, with a voltage regulation range of 0-30V and a power of 150W; the model of the voltage measuring device 2 is Tektronix DMM6500 desktop multimeter, with a DC voltage range of ±100nV-±1000V; the current measuring device 6 is Shanghai Chenhua CHI760e electrochemical workstation, with a current measurement range of ±10pA-±0.25mA; the surface temperature difference measuring device 5 is Uni-T UT325 high-precision temperature measuring instrument, equipped with a K-type thermocouple, with a temperature measurement range of -50-500℃; the variable resistor 7 is Zhiyu Electronics precision adjustable resistance box.

[0034] The implementation principle of the embodiment of the present application is:

[0035] The components are connected according to the connection relationship described in the above embodiment, and then the quasi-solid sample 10 to be tested is placed on the TEC refrigeration plate 9. At this time, both ends of the quasi-solid sample 10 are supported by the TEC refrigeration plate 9, and the middle part of the quasi-solid sample 10 is supported by the thermal conductive filling copper block 11, and the middle part is closely attached to the circulating water heat exchanger 8 through the thermal conductive filling copper block 11, which not only provides effective heat dissipation for the TEC refrigeration plate 9 and ensures its stable operation; it also provides a constant temperature test environment for the quasi-solid sample 10, saving complex external environmental temperature control equipment.

[0036] The quasi-solid sample 10 to be measured is Figure 6 As shown, the TEC cooling sheet 9, the heat conductive copper block 11, the measuring electrode and the temperature probe are covered. The super constant temperature circulating water bath 4 and the circulating water heat exchanger 8 are turned on to keep the rest of the quasi-solid sample 10 at a constant temperature except for the cold and hot ends; the super constant temperature circulating water bath 4 is set to the temperature required for the experiment.

[0037] The power supply and temperature control method of the TEC cooling sheet 9 adopts a cheap and readily available DC constant voltage adjustable power supply 3. By adjusting the voltage of the DC constant voltage adjustable power supply 3, the hot end / cold end TEC cooling sheet 9 can be powered to provide a cold / hot temperature difference. According to Ohm's law I=U / R, when the voltage is constant, the operating power of the TEC cooling sheet 9 is fixed, so a constant temperature difference can be provided.

[0038] The quasi-solid sample 10 can generate thermovoltage under a temperature difference environment, and the open circuit voltage can be directly measured by the voltage measuring device 2. The open circuit voltage under different temperature differences is measured and linear fitting is performed, and the slope is the Seebeck coefficient ( Figure 1 When measuring the output current and power, the parallel circuit where the variable resistor 7 and the current measuring device 6 are located is connected, and different resistance values ​​are adjusted to measure the voltage and current under different loads. After fitting, the current-voltage curve and power curve are obtained ( Figure 2 ).

[0039] According to Wang et al. (Wang S., Li Y., Yu M. et al. High-performance cryo-temperatureionic thermoelectric liquid cell developed through a eutectic solvent strategy. Nat Commun 15, 1172 (2024).) and Xu et al. (C. Xu, Y. Song, J. Zhang, W. Xu, H. Tian. Adaptable and Wearable Thermocell Based on Stretchable Hydrogel for Body Heat Harvesting. Advanced Energy Materials 2022, 12 (42), 2201542), the potassium ferrocyanide / potassium ferrocyanide temperature-sensitive redox couple exhibits a Seebeck coefficient of about 1.4 mV / K in an aqueous system.

[0040] In addition, the research of Migita et al. (Tsubasa MIGITA, Naoki TACHIKAWA, Yasushi KATAYAMA, Takashi MIURA. Thermoelectromotive Force of Some Redox Couples in an Amide-type Room-temperature Ionic Liquid. Electrochemistry, 2009, 77, 639–641.) and Liu et al. (Y. Liu, Q. Zhang, GOOdunmbaku, Y. Zhang, S. Chen, Y. Zhou, J. Li, K. Sun. Solvent effect on the Seebeck coefficient of Fe2+ / Fe3+ hydrogel thermogalvanic cells. J. Mater. Chem. A, 2022, 10, 19690-19698) mentioned that the Seebeck coefficient of ferric chloride / ferrous chloride in water system is about 1.17 mV / K. Figure 1 and Figure 2Respectively, the Seebeck coefficient of quasi-solid materials based on potassium ferrocyanide / potassium ferrocyanide and ferric chloride / ferrous chloride was measured using the device of the present application, wherein the materials contained 20wt% polyacrylamide, 0.006wt% N,N-methylenebisacrylamide, and 80wt% electrolyte containing 0.4mol / L potassium ferrocyanide / potassium ferrocyanide or ferric chloride / ferrous chloride solution. It was found that the Seebeck coefficient of the thermoelectric gel based on the potassium ferrocyanide / potassium ferrocyanide couple was equal to 1.404±0.011mV / K, while the Seebeck coefficient of the thermoelectric gel based on ferric chloride / ferrous chloride was -1.135±0.004mV / K, which is basically consistent with the above report. In addition, the voltage-current curve and power curve of the gel were measured using the device at a temperature difference of 40K on this device, as shown in FIG. Figure 3 and Figure 4 shown.

[0041] The above description is only a preferred specific implementation manner of the present invention; however, the protection scope of the present invention is not limited thereto; any technician familiar with the technical field within the technical scope disclosed by the present invention; any equivalent replacement or change based on the technical solution and improved concept of the present invention shall be covered by the protection scope of the present invention.

Claims

1. A device for measuring performance parameters of a quasi-solid-state thermoelectric heating device, characterized in that: The invention comprises a pair of TEC cooling sheets (9) and a circulating water heat exchanger (8) arranged in parallel, wherein the heating surface of one TEC cooling sheet (9) faces upwards, and the cooling surface of the other TEC cooling sheet (9) faces upwards; the bottom of the TEC cooling sheet (9) is detachably connected to the circulating water heat exchanger (8); the circulating water heat exchanger (8) is connected to a constant temperature circulating water bath for providing constant temperature circulating water; the pair of TEC cooling sheets (9) are electrically connected to a direct current constant voltage adjustable power supply (3); and the TEC is also electrically connected to a measuring circuit for measuring the performance parameters of a quasi-solid-state thermoelectric heating device.

2. A quasi-solid-state thermoelectric heating device performance parameter measuring device according to claim 1, characterized in that: The distance between two TEC cooling sheets (9) is 3-5 cm.

3. The device for measuring performance parameters of a quasi-solid-state thermoelectric heating device according to claim 1, characterized in that: The bottoms of a pair of TEC refrigeration sheets (9) are coated with thermally conductive silicone grease, and the TEC refrigeration sheets (9) are adsorbed on the circulating water heat exchanger (8) through the thermally conductive silicone grease.

4. The device for measuring performance parameters of a quasi-solid-state thermoelectric heating device according to claim 1, characterized in that: It also includes a heat-conducting support member, which is placed between a pair of TEC refrigeration sheets (9), and the bottom of the heat-conducting support member is in contact with the circulating water heat exchanger (8).

5. The device for measuring performance parameters of a quasi-solid-state thermoelectric heating device according to claim 4, characterized in that: The heat-conducting support member comprises a heat-conducting filling copper block (11).

6. The device for measuring performance parameters of a quasi-solid-state thermoelectric heating device according to claim 1, characterized in that: The measurement circuit comprises an electrical parameter measurement circuit and a surface temperature difference measurement circuit; the surface temperature difference measurement circuit comprises a pair of temperature probes, and the electrical parameter measurement circuit comprises a pair of measurement electrodes; the temperature probes and the measurement electrodes both pass through the quasi-solid sample to be measured, and respectively abut against a pair of TEC cooling sheets (9) in one-to-one correspondence; the spacing between the temperature probes and the measurement electrodes located on the same TEC cooling sheet (9) is ≤5 mm.

7. A device for measuring performance parameters of a quasi-solid-state thermoelectric heating device according to claim 6, characterized in that: The temperature probe comprises a thermocouple or a thermal resistance probe, and the measuring electrode comprises a platinum electrode.

8. The device for measuring performance parameters of a quasi-solid-state thermoelectric heating device according to claim 6, characterized in that: The electrical parameter measurement circuit comprises a voltage measurement circuit and a current measurement circuit, wherein the voltage measurement circuit and the current measurement circuit are connected in parallel; the voltage measurement circuit comprises a voltage measurement device (2), and the current measurement circuit comprises a current measurement device (6) and a variable resistor (7) connected in series.

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