Self-energy-taking temperature and pressure coupling sensing device and method

Abstract

The invention relates to the field of thermoelectric devices, and provides a self-energy-taking temperature and pressure coupling sensing device and method. The device comprises a thermoelectric device and a circuit board. The circuit board comprises a boost module, a capacitor and a Bluetooth module, the boost module is connected with the capacitor, and the other end of the capacitor is connected with the Bluetooth module; two ends of the thermoelectric device are respectively connected with leads, and the other ends of the leads are connected to the printed circuit board. According to the device, the flexible substrate and the rigid particles are adopted, novel circuit design is combined, output voltage of each unit can be measured and transmitted in real time while energy is provided for a system, and finally temperature and voltage information is displayed on a terminal.

Description

Technical Field

[0001] The present application relates to the field of thermoelectric devices, and in particular to a self-energy-collecting temperature-pressure coupled sensing device and method. Background Art

[0002] With the rapid development of IoT technology, it is estimated that by 2025, there will be more than 75 billion IoT devices. Most of these devices rely on wireless sensor systems and micro power systems, while traditional node devices usually use secondary batteries as a power supply, which not only increases the maintenance cost of the equipment, but also brings the problem of recycling and processing of waste batteries. Therefore, exploring self-powered energy systems is of great significance to further improve the construction and development of IoT.

[0003] Based on the Seebeck effect, thermoelectric devices can convert heat energy in the environment into electrical energy, with the characteristics of no by-products and continuous energy supply. At the same time, since the output voltage and internal resistance of thermoelectric devices are closely related to the external temperature, they are also highly temperature sensitive. In recent years, flexible thermoelectric sensing thermoelectric devices have shown broad application prospects in energy harvesting and temperature sensing due to their unique flexibility and temperature sensitivity.

[0004] However, although existing flexible thermoelectric sensing devices based on organic thermoelectric materials such as PEDOT:PSS have excellent flexibility and temperature linearity, their actual output power is low and it is difficult to drive external temperature measurement circuits. Summary of the invention

[0005] In response to the above problems, this application proposes a self-energy temperature and pressure coupling sensing device and method. The device uses a flexible substrate and rigid particles, combined with a novel circuit design, to provide energy to the system while being able to measure and transmit the output voltage of each unit in real time, and finally display the temperature and voltage information on the terminal.

[0006] To achieve the above objectives, this application adopts the following technical solutions: In a first aspect, the present application provides a self-energy temperature and pressure coupled sensing device, comprising a thermoelectric device and a circuit board; a plurality of thermoelectric devices are arranged on the circuit board at intervals; The circuit board includes a boost module, a capacitor and a Bluetooth module, the boost module is connected to the capacitor, and the other end of the capacitor is connected to the Bluetooth module; Two ends of the thermoelectric device are connected to wires respectively, and the other ends of the wires are connected to a printed circuit board.

[0007] As a further improvement of the present invention, the material of the thermoelectric device satisfies that the resistivity changes linearly with temperature in the temperature measurement section, so that the internal resistance of the thermoelectric device is linearly related to the average temperature at both ends of the device, and the open circuit voltage of the thermoelectric device is linearly related to the temperature difference at both ends of the device.

[0008] As a further improvement of the present invention, the thermoelectric device uses p-type and n-type thermoelectric materials.

[0009] As a further improvement of the present invention, the material of the thermoelectric device is one or more of Bi2Te3-based compounds, Ag2Q-based compounds, SnSe-based compounds, Mg2Si-based compounds, MgAgSb-based compounds, MgSiSn-based compounds and Mg3Sb2-based compounds, wherein Q=S, Se or Te.

[0010] As a further improvement of the present invention, the material of the thermoelectric device is n-type Bi2Te 2.7 Se 0.3 and p-type Bi 0.5 Sb 1.5 Te3 material.

[0011] As a further improvement of the present invention, the internal resistance of a single thermoelectric device is below 3Ω.

[0012] As a further improvement of the present invention, the model of the boost module is LTC3108; the model of the Bluetooth module is nRF52832.

[0013] As a further improvement of the present invention, each of the thermoelectric devices and the circuit board is connected to form a plurality of π-type units.

[0014] As a further improvement of the present invention, there are multiple thermoelectric devices, adjacent thermoelectric devices are connected in series, and each thermoelectric device has the same cold and hot ends.

[0015] As a further improvement of the present invention, the circuit board is a printed circuit board; the wires are connected to the circuit board by welding.

[0016] As a further improvement of the present invention, the thermoelectric device is prepared by combining a flexible substrate and rigid particles.

[0017] In a second aspect, the present application also provides a method for preparing a self-energy temperature and pressure coupled sensing device, comprising: Fix the substrate; Use dispensing or screen printing technology to tin the corresponding position of the substrate electrode; The tin-coated substrate is placed on a positioning base, and a positioning grid is placed on the substrate to sequentially place the p-type and n-type material particles. The upper and lower substrates after the film swinging are attracted by magnetic force and placed in a vacuum eutectic furnace for welding; After welding, cutting is performed to obtain a thermoelectric device; Thermoelectric devices are assembled to obtain a self-energy-collecting temperature and pressure coupled sensing device.

[0018] As a further improvement of the present invention, the method for preparing p-type and n-type material particles comprises: Slice the hot extruded material rods, measure and match the thickness of the sliced ​​p-type and n-type material sheets, and obtain sheets that meet the thickness requirements; The screened sheets are subjected to surface treatments of chemical Ni plating and electroplating of Au layers; The surface treated sheet is pelletized to obtain p- and n-type material particles.

[0019] As a further improvement of the present invention, thickness measurement and matching of sliced ​​p-type and n-type material sheets are performed, specifically including: The ttv of a single sheet is controlled within 5μm, and the thickness difference between p-type and n-type sheets is within 15μm.

[0020] Compared with the prior art, this application has the following advantages: The self-energy temperature and pressure coupling sensing device provided by the present application includes a thermoelectric device and a circuit board. The thermoelectric device can convert the temperature difference in the environment into electrical energy, and the circuit board is responsible for the boost, storage and transmission of the electrical energy. The circuit board includes a boost module, a capacitor and a Bluetooth module. When the thermoelectric device is heated by a heat source, electrical energy is generated, and the electrical energy is transmitted to the boost module on the circuit board through a wire. The boost module boosts the low-voltage electrical energy to a voltage range suitable for the operation of the Bluetooth module. The capacitor stores the boosted electrical energy and releases it to the Bluetooth module when needed. After receiving the electrical energy, the Bluetooth module starts working and transmits the sensing data wirelessly to an external device. Therefore, the thermal energy in the environment is converted into electrical energy by the thermoelectric device, achieving energy self-sufficiency. This avoids the dependence of traditional sensing devices on external power supplies, reduces installation and maintenance costs, and also reduces energy consumption and environmental pollution. Due to the ability to power itself, the sensing device can continue to operate without external power support, improving the reliability and stability of the system. This is particularly important for Internet of Things applications that require long-term monitoring. The sensor device can monitor both temperature and pressure parameters at the same time, providing more comprehensive information for the safety warning system. This helps to detect potential safety hazards in a timely manner and improve the system's early warning capabilities.

[0021] Furthermore, by optimizing the structure and circuit design of the thermoelectric device, the sensor device can achieve high-precision temperature and pressure measurement. This ensures the accuracy and reliability of the monitoring data. The self-energy temperature and pressure coupling sensor device has significant advantages in energy self-sufficiency, temperature and pressure coupling perception capability, high efficiency and reliability, wide applicability and flexibility, and cost-effectiveness. These advantages make the sensor device have broad application prospects and market competitiveness in the self-powered and safety warning systems of Internet of Things (IoT) devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the principle of self-energy temperature measurement in this application; Figure 2 This is a test data diagram of the temperature measurement reliability of this application; (a) is a small temperature range, and (b) is a large temperature range; Figure 3 It is a design drawing of an independent substrate for each unit of the thermoelectric device in the example of the present application; Figure 4 The figures are power generation performance diagrams of the thermoelectric device in the example of the present application at different temperature differences; (a) is 10K, (b) is 10K, and (c) is 30K; Figure 5 is a graph showing the response of different units of the thermoelectric device to touch in an example of the present application; Figure 6 This is a graph showing the power generation performance of the thermoelectric device in the present application example when it is touched by a finger for a long time; Figure 7 This is a diagram of the power generation performance of the thermoelectric device in the example of this application in a wearable environment. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0024] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only embodiment.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0026] In order to better understand the present application, the content of the present application is further explained below in conjunction with the embodiments, but the content of the present application is not limited to the following embodiments.

[0027] The present application relates to the field of thermoelectric devices, and specifically to a self-energy temperature-pressure coupled sensing device. The thermoelectric device can simultaneously realize energy supply and temperature-pressure sensing functions, and is particularly suitable for self-powered and safety warning systems of Internet of Things (IoT) devices.

[0028] As a solution to achieve the above-mentioned purpose, this embodiment provides a self-energy temperature and pressure coupled sensing device, which includes a thermoelectric device and a circuit board, wherein the circuit board includes a boost module, a capacitor and a Bluetooth module, wires are welded at both ends of the thermoelectric device, and the other ends of the wires are welded to the printed circuit board, the boost module on the circuit board is connected to the capacitor, and the other end of the capacitor is connected to the Bluetooth module.

[0029] The device mainly consists of two parts: thermoelectric devices and circuit boards. The thermoelectric devices are responsible for converting the temperature difference in the environment into electrical energy, while the circuit boards are responsible for boosting, storing and transmitting the electrical energy. The key components on the circuit boards include boost modules, capacitors and Bluetooth modules.

[0030] Thermoelectric devices work based on the thermoelectric effect, that is, when there is a temperature difference between the two ends of a conductor of two different materials, an electric potential difference is generated inside the conductor, which drives the flow of electrons to form an electric current. In this device, the two ends of the thermoelectric device are connected to wires, and the other ends of the wires are connected to the printed circuit board to form a closed loop. When the thermoelectric device is heated by a heat source, the heat energy is converted into electrical energy and transmitted to the circuit board through the wires.

[0031] The boost module is responsible for boosting the low voltage power generated by the thermoelectric device to a voltage range suitable for the Bluetooth module. This is because the power generated by the thermoelectric device is often low and cannot directly drive low-power electronic devices such as the Bluetooth module. The capacitor is used to store the power output by the boost module and release it to the Bluetooth module when needed. This helps smooth out voltage fluctuations and ensures stable operation of the Bluetooth module. The Bluetooth module is responsible for wirelessly transmitting data on the circuit board to external devices (such as mobile phones, computers, etc.). In this device, the Bluetooth module may be used to transmit sensor data such as temperature and pressure.

[0032] The working process is as follows: The thermoelectric device is heated by a heat source to generate electrical energy. The electrical energy is transmitted to the boost module on the circuit board through wires. The boost module boosts the low-voltage electrical energy to a voltage range suitable for the operation of the Bluetooth module. The capacitor stores the boosted electrical energy and releases it to the Bluetooth module when needed. After receiving the electrical energy, the Bluetooth module starts working and wirelessly transmits the sensor data to external devices.

[0033] The device converts the temperature difference in the environment into electrical energy through thermoelectric devices, without the need for external power supply, reducing installation and maintenance costs. The device can monitor both temperature and pressure parameters at the same time, providing more comprehensive information for the safety warning system. The Bluetooth module realizes wireless data transmission, facilitating remote monitoring and management. The device uses the temperature difference in the environment to generate electricity, without consuming traditional energy, in line with the concept of energy conservation and environmental protection.

[0034] The core of the self-energy temperature and pressure coupled sensing device of this application is to achieve energy self-sufficiency and dual sensing functions of temperature and pressure through thermoelectric devices, which is very suitable for the self-energy and safety warning system of Internet of Things (IoT) devices. The principle is as follows: Thermoelectric devices, also known as thermocouples or thermopiles, work based on the thermoelectric effect. The thermoelectric effect refers to the fact that when there is a temperature difference between the two ends of a material, an electric potential difference is generated inside the material, thereby generating an electric current. This effect can be used to convert thermal energy into electrical energy, or to sense temperature differences by measuring the potential difference. In this application, the thermoelectric device is designed to respond to changes in temperature and pressure at the same time. This is usually achieved by arranging and combining thermoelectric materials (such as Bi2Te3-based thermoelectric materials) in a specific way. When the thermoelectric device is subjected to pressure, the thermoelectric material inside it may deform, resulting in changes in resistance or thermoelectric coefficient, thereby indirectly reflecting changes in pressure. At the same time, due to the thermoelectric effect, the thermoelectric device can also directly sense and respond to changes in temperature.

[0035] The printed circuit board (PCB) is another important component in this application. It contains key components such as a boost module, capacitors, and a Bluetooth module. Since the voltage generated by thermoelectric devices is usually low, it needs to be boosted to a sufficiently high level by a boost module for use in subsequent circuits. The boost module achieves voltage boost by adjusting the relationship between current and voltage in the circuit. Capacitors are used to store electrical energy and release it when needed. In this application, the capacitor can smooth the voltage output by the boost module and provide a stable power supply. The Bluetooth module is responsible for wirelessly transmitting information such as the temperature and pressure measured by the sensor device and the voltage generated by the thermoelectric device to the terminal device. In this way, the user can view this information in real time through the terminal device.

[0036] Based on the above technical solution, the present application can achieve energy self-sufficiency, convert the thermal energy in the environment into electrical energy through thermoelectric devices, and provide energy for the entire sensing device. This self-sufficient method reduces the dependence on traditional power sources and improves the reliability and flexibility of the system. Temperature and pressure coupling perception can also be performed. Thermoelectric devices can not only sense changes in temperature, but also indirectly sense changes in pressure through the deformation of their internal structures. This coupled sensing function enables the sensing device to monitor both temperature and pressure parameters at the same time, providing more comprehensive information for the safety warning system. The use of efficient thermoelectric materials and precise processing technology has significantly improved the output power and power density of thermoelectric devices. At the same time, by optimizing the circuit design and structural design, the node load equipment is reduced, and the integration and reliability of the system are improved.

[0037] The self-energy temperature and pressure coupled sensing device proposed in this application. The system uses a flexible substrate and rigid particles, combined with circuit design, to provide energy to the system while being able to measure and transmit the output voltage of each unit in real time, and finally display the temperature and voltage information on the terminal. The main features of this application are: In terms of structural design, by optimizing the structure and circuit design of thermoelectric devices, the integration of energy supply and temperature and pressure coupling perception is achieved, the node load equipment is reduced, and the integration and reliability of the system are improved. For example, high-efficiency p-type and n-type Bi2Te3-based thermoelectric materials can be used, combined with precise processing technology, to significantly improve the output power and power density of thermoelectric devices. Thermoelectric devices respond quickly to temperature changes and can accurately sense ambient temperature changes in a short time. Thermoelectric devices are highly flexible and can adapt to a variety of complex environments. They are widely used in wearable devices, smart homes, industrial monitoring and other fields.

[0038] In some optional implementation schemes, the self-energy temperature and pressure coupling sensor device can generate electrical energy under the action of the temperature difference between the surface of the thermoelectric device and the environment, and store the electrical energy after passing through the pressure generating device to power the Bluetooth module. The Bluetooth module sends the collected voltage signal to the receiving device, and after post-processing, the temperature at both ends of the device is obtained and displayed.

[0039] In some optional embodiments, the internal resistance of a single thermoelectric device is below 3Ω. The circuit board may be a printed circuit board.

[0040] In some optional embodiments, the materials used in the thermoelectric device are Bi2Te3-based compounds, Ag2Q (Q=S, Se, Te)-based compounds, SnSe-based compounds, Mg2Si-based compounds, MgAgSb-based compounds, MgSiSn-based compounds and Mg3Sb2-based compounds.

[0041] Among them, Bi2Te3-based compounds are currently the best thermoelectric conversion materials with the best performance near room temperature and are widely used in the field of refrigeration. This material is small in size, noiseless, long in life, does not release harmful substances, and is environmentally friendly. It is sensitive, highly accurate, can be installed and operated at any angle, and has no moving parts.

[0042] Ag2Q (Q=S,Se,Te) based compounds: complex crystal structure, high carrier mobility and low lattice thermal conductivity. This makes this material have potential application value in the field of thermoelectrics. Its thermoelectric performance can be further optimized by adjusting the composition and controlling the phase structure.

[0043] SnSe-based compounds: SnSe-based crystalline materials have high thermoelectric properties, low cost and abundant reserves. They perform well in thermoelectric power generation and electronic refrigeration and have great application potential. Compared with traditional thermoelectric materials, SnSe has better processability and is easy to manufacture devices.

[0044] Mg2Si-based compounds have excellent thermoelectric properties: Mg2Si is a thermoelectric material with excellent performance in the temperature range of 500K~800K. Abundant raw materials and low prices: Its constituent elements are characterized by abundant raw materials and low prices.

[0045] MgAgSb-based compounds: high ZT value, MgAgSb-based materials have a high ZT value near room temperature, filling the temperature gap between Bi2Te3 materials and medium temperature zone materials. When the cold end is room temperature and the temperature difference is 225 degrees Celsius, the conversion efficiency of a single-arm device reaches 8.5%.

[0046] MgSiSn-based compounds and others (such as Mg3Sb2-based compounds), potential thermoelectric properties: These materials also have certain application potential in the thermoelectric field. Through further research and development, more excellent thermoelectric properties are expected to be discovered.

[0047] In some optional embodiments, the model of the boost module includes but is not limited to LTC3108. As a highly integrated DC / DC converter, LTC3108 is very suitable for collecting and managing surplus energy from extremely low input voltage power supplies. Its boost topology enables it to operate normally with an input voltage as low as 20mV, which provides great flexibility for energy harvesting applications. In terms of functions, LTC3108 can achieve a variety of functional expansions through different configurations and peripheral circuits, such as adding protection circuits, adjusting output voltage, etc., to meet the needs of different applications.

[0048] For example, the boost module LTC3108 can consider: ZCC1708, which is also a highly integrated DC power converter that can collect and manage surplus energy from very low input voltage sources. Compared with LTC3108, ZCC1708 may be different in terms of minimum operating input voltage, output voltage selection, and packaging, but it is also suitable for collecting surplus energy for low-power wireless sensors and other applications.

[0049] In some optional implementation schemes, the model of the Bluetooth module includes but is not limited to nRF52832. nRF52832 is a powerful multi-protocol single-chip solution that supports low-power Bluetooth, ANT, and 2.4GHz proprietary protocol stacks. By integrating the NFC-A tag interface, it also supports OOB pairing function. nRF52832 has rich peripheral interfaces and powerful processing capabilities, and can be used in combination with other sensors, actuators or communication modules to achieve more complex functions and applications. nRF52832 uses a high-performance ARM Cortex-M4F CPU and sufficient memory resources (512kB flash and 64kBRAM), which gives it a significant advantage in processing complex tasks and high-speed data transmission. The performance of nRF52832 can be further improved by optimizing software algorithms, improving hardware design, etc., such as reducing power consumption and increasing communication rate.

[0050] For example, the Bluetooth module nRF52832 can also consider: PHY6212, which is a Bluetooth wireless chip with a 32-bit ARM Cortex-M0 CPU, 138K SRAM and BLE support. Compared with nRF52832, PHY6212 may differ in processor performance, memory capacity, and power consumption, but it is also suitable for applications such as smart wearables and indoor navigation. In addition, PHY6212 also has low power consumption characteristics and multiple wake-up options, which can be used as a low-cost alternative to nRF52832.

[0051] The temperature measurement principle of the technical solution of this application is: The self-energy temperature and pressure coupling sensor device in this embodiment connects multiple π-type units in a thermal parallel and electrical series manner.

[0052] As a preferred solution, Figure 1 As shown, to obtain the temperature across the thermoelectric device, two equations related to the device temperature are required. First, the open circuit voltage U oc It can be expressed as: (1) In the formula S TEG is the overall Seebeck coefficient of the device, T cand T h are the temperatures of the upper and lower surfaces of the device, respectively. The Seebeck coefficient is used to measure the rate of energy change of a substance, especially the relationship between temperature and potential difference in electronic thermodynamics.

[0053] Hun Sik Hana studied the effect of temperature on the internal resistance of thermoelectric devices. The results showed that under different hot-end temperatures and hot-cold-hot temperature differences, the internal resistance of the device changes linearly and is proportional to the average temperature of the hot and cold surfaces of the device. When the types and sizes of p- and n-type materials are consistent, the thermal conductivity of each thermoelectric device (thermoelectric arm) is consistent. When the device fully exchanges heat with the environment to establish thermal equilibrium, due to the symmetry of its sandwich structure, the upper and lower surfaces of the device have the same temperature gradient, and its average temperature is T 1 and T 2, so the relationship between the internal resistance of the device and temperature can be expressed as: (2) In the formula, α TEG is the temperature coefficient of resistance of the thermoelectric device, T avg is the average temperature of the device.

[0054] Therefore, according to equations (1) and (2), the open circuit voltage of the thermoelectric device is detected by an external circuit. U oc and internal resistance (here is ACR to eliminate Peliter effect), the upper and lower surface temperatures of the device are expressed by equation (3): (3) (4) According to the formula, when α TEG and S TEG When a is a constant, as long as the ACR and open circuit voltage of the thermoelectric device are known, the temperature of the upper and lower surfaces of the device can be calculated to achieve temperature testing. TEG and S TEG is a constant, and has the following requirements for materials: First, the open circuit voltage of the thermoelectric device is linearly related to the temperature difference at both ends of the device, which requires that the total Seebeck coefficient of the device is relatively stable during the temperature measurement period; second, the internal resistance of the thermoelectric device is linearly related to the average temperature at both ends of the device, which requires that the resistivity of the material used in the device changes linearly with the temperature during the temperature measurement period. 2.7 Se 0.3 and p-type Bi 0.5 Sb 1.5 Te3 material properties can meet the conditions, material properties such as Figure 1shown.

[0055] By measuring the output voltage of the thermoelectric device, the ambient temperature changes can be sensed in real time and the relevant information can be transmitted to the terminal for display. Figure 2 Demonstrated its reliability in temperature measurement function.

[0056] Based on the above scheme, in the self-energy temperature and pressure coupling sensing device in this embodiment, multiple π-type units are connected in parallel by thermal parallel and electrical series. First, thermal parallel means that multiple π-type units are connected in parallel on the heat transfer path. This means that the hot end and the cold end of each π-type unit are connected together to form a common hot end and cold end. In this way, when there is a temperature difference, each π-type unit can independently convert thermal energy into electrical energy without interfering with each other. This parallel connection method improves the thermal energy conversion efficiency of the entire device because more thermoelectric materials are used for thermal energy conversion, thereby generating more electrical energy. Secondly, electrical series connection means that the output ends of multiple π-type units are connected in series in the circuit. This means that the electrical energy generated by each π-type unit will be added in sequence to form a total output voltage. This series connection method increases the output voltage of the entire device, making it easier for the device to drive subsequent circuits or devices. At the same time, since the current in the series circuit is equal everywhere, the operating current of each π-type unit is also the same, which helps to maintain the stability and reliability of the entire device.

[0057] Each π-type unit may be composed of P-type and N-type thermoelectric materials, which are connected together by metal plates or wires to form a thermocouple. When there is a temperature difference between the two ends of the thermocouple, the holes in the P-type material and the electrons in the N-type material will move from the hot end to the cold end, forming a potential difference and generating current. In the thermal parallel and electrical series connection mode, multiple π-type units can work together to convert more thermal energy into electrical energy and output a higher voltage. Connecting multiple π-type units in thermal parallel and electrical series can improve the thermal energy conversion efficiency and output voltage of the self-energy temperature and pressure coupling sensor device, so that it has better performance and wider application prospects in practical applications. This connection method also reflects the arrangement principle of "thermal parallel and electrical series" in the design of thermoelectric components, that is, the thermoelectric devices are connected in series, but each thermoelectric device has the same hot and cold ends. This structure helps to optimize the performance and reliability of thermoelectric components.

[0058] The self-energy temperature and pressure coupling sensor device proposed in this embodiment brings the following effects: Self-powered and integrated sensing: The thermoelectric device not only provides energy for the system, but also has temperature sensing capability, realizing the integration of power supply and sensing, effectively reducing the number of node load devices, and reducing the complexity and cost of the system.

[0059] High energy conversion efficiency: Under constant temperature difference conditions (such as 30K temperature difference), the thermoelectric device can achieve a high open circuit voltage (such as 934 mV) and normalized power density (such as 5.26 μW·cm -2 ·K -2 ), indicating that it has a high energy conversion efficiency.

[0060] Real-time temperature monitoring: The system can measure the output voltage of each unit separately and send real-time circuit information to the terminal, and finally display the relationship between temperature and voltage on the terminal, realizing real-time monitoring of ambient temperature.

[0061] Expanding application scenarios: The design of this thermoelectric device provides new ideas for thermoelectric devices and broadens the application scenarios of thermoelectric devices, especially in Internet of Things (IoT) devices, and can serve as an ideal power supply and sensing unit for node devices.

[0062] Improve the limitations of traditional node equipment: Compared with traditional node equipment powered by secondary batteries, this thermoelectric device does not require regular battery replacement, which reduces equipment maintenance costs and the problem of waste battery recycling and treatment, and is more in line with the needs of sustainable development.

[0063] High temperature sensitivity and response speed: By optimizing the thermal interface design and adopting new thermoelectric materials, the thermoelectric device has high sensitivity and fast response speed to temperature changes, and can reflect changes in ambient temperature in real time.

[0064] Thermoelectric devices use a combination of flexible substrates and rigid particles, and have the characteristics of flexible design, making the entire system flexible and wearable, and suitable for various complex environments and usage scenarios.

[0065] These beneficial effects together constitute the unique advantages and value of this integrated sensing-supply flexible thermoelectric device system.

[0066] The present application is described in detail below with reference to specific embodiments and drawings.

[0067] Example 1 Material selection and processing instructions are as follows: This embodiment uses commercial hot-extruded n-type Bi2Te with both energy extraction and temperature measurement performance 2.7 Se 0.3 and p-type Bi 0.5 Sb 1.5Te3 material is used as the material for thermoelectric devices. First, the hot extruded material rod with a diameter of 30 mm is sliced, and the cutting thickness is set to 0.8, 1.2 and 1.6 mm respectively. The thickness of the sliced ​​p-type and n-type material sheets is measured and matched to ensure that the TTV (Total Thickness Variation) of a single sheet is controlled within 5 μm, and the thickness difference between the p-type and n-type sheets is within 15 μm. Subsequently, the surface of the screened sheet is treated with chemical Ni plating and electroplating Au layer to enhance the weldability of the thermoelectric device. Finally, the electroplated material is pelletized to obtain a thermoelectric device with a size of 0.8×0.8 mm³.

[0068] The preparation process of thermoelectric devices is as follows: The assembly process of thermoelectric devices adopts the mold positioning method, which includes the steps of substrate fixing, thermoelectric device dispensing / printing solder paste, film swinging, welding, substrate cutting, etc. The specific steps are as follows: Substrate fixing: Fix the substrate on the mold by magnetic attraction.

[0069] Electrode tinning: Use dispensing or screen printing technology to coat the corresponding positions of the substrate electrodes with tin.

[0070] Film swing: Place the tin-coated substrate on the positioning base, cover it with a positioning grid, and then perform film swing on the p-type and n-type material particles in turn.

[0071] Welding: After the film is swung, the upper and lower substrates are magnetically attracted and placed in a vacuum eutectic furnace for welding. The welding process is divided into two steps, forward and reverse, to ensure the accuracy and consistency of welding.

[0072] Substrate cutting and cleaning: After welding, the substrate on the thermoelectric device is cut and the thermoelectric device is cleaned.

[0073] In order to realize the tactile sensing function of self-energy extraction, the present application designs the structure of the thermoelectric device so that it can provide the voltage required for transmitting signals while measuring temperature and make the substrate flexible. Figure 3 This is a physical picture of a thermoelectric device. The thermoelectric device is divided into four modules. The four modules are connected in series. The circuit is designed so that the application can monitor the voltage of each module separately. Figure 4 To test the power generation capacity of thermoelectric devices under constant temperature difference conditions, the cold end temperature of the thermoelectric device is kept constant at 22°C during the test, and the thermoelectric device is placed on a heating platform. When there is a temperature difference of 10K across the thermoelectric device, as the load changes, the thermoelectric device can reach a maximum open circuit voltage of 316mV. As the temperature difference increases, the output power of the thermoelectric device will also increase, and can reach an open circuit voltage of 934mV at a temperature difference of 30K.

[0074] At the same time, the signal response when a finger touches the upper surface of the thermoelectric device was tested to verify the thermoelectric device's ability to sense temperature, and the temperature response rate of the thermoelectric device's output voltage and ACR was studied. The thermoelectric device was placed on a glass plate, and the four units were connected to 34972A for voltage signal acquisition. Figure 5 Four units are stimulated at intervals with fingers at room temperature. As can be seen from the figure, each unit of the thermoelectric device is very sensitive to temperature changes.

[0075] Figure 6 It shows that when the ambient temperature is 18℃, the entire thermoelectric device is pressed with a finger. The output voltage of the thermoelectric device will quickly reach a peak value of 62.9mV and gradually decrease over time. This is because as the pressing time increases, the heat from the hot end of the thermoelectric device will gradually transfer to the cold end, reducing the temperature difference between the cold and hot surfaces of the thermoelectric device, so the output voltage will also decrease. When the thermoelectric device is worn on the arm, the output voltage of the thermoelectric device will reach a peak value of 120mV at 4s and reach a relatively stable output voltage of 20mV at 12s. The test results are as follows Figure 7 The output voltage of the thermoelectric device decreases faster when it is worn on the arm because the arm has more heat than the finger. Therefore, it takes a shorter time for both ends of the thermoelectric device to reach equilibrium. If the heat dissipation capacity of the cold surface of the thermoelectric device is increased, the output voltage will be higher when worn on the arm.

[0076] Furthermore, this embodiment uses highly efficient p-type and n-type Bi2Te3-based thermoelectric materials, combined with precise processing technology, to significantly improve the output power and power density of the thermoelectric device. This makes the sensor device more efficient in energy conversion and transmission.

[0077] By optimizing the circuit design, the node load equipment is reduced, and the integration and reliability of the system are improved. This helps to reduce the failure rate of the system and extend its service life. Thermoelectric devices are highly flexible and can adapt to a variety of complex environments. This allows the sensing device to be widely used in wearable devices, smart homes, industrial monitoring and other fields to meet the needs of different scenarios. The sensing device is small in size and light in weight, and is easy to integrate with other IoT devices. This helps to build a more intelligent and efficient IoT system. By adding additional sensors or functional modules, the function and application range of the sensing device can be further expanded. This provides users with more choices and flexibility.

[0078] Since no external power supply is required, the installation cost of the sensor device is relatively low. This helps reduce the overall cost of the IoT system. By being autonomously powered and operating efficiently, the sensor device can reduce energy consumption and maintenance costs, bringing long-term economic benefits to users.

[0079] Example 2 A self-energy temperature and pressure coupling sensing device, specifically comprising the following: In this embodiment, MgAgSb-based thermoelectric materials and Mg3Sb2-based thermoelectric materials with excellent thermoelectric properties are used to make thermoelectric devices with a size of 0.8×0.8mm³, and a single micro-device unit with a size of 6 mm×14 mm×2.5 mm is prepared together with an alumina substrate, a copper electrode, and SAC305 solder. Four units are connected in series to form a self-energy temperature and pressure coupled sensing device.

[0080] The self-energy temperature and pressure coupling sensor device is applied to the plum blossom contacts of the high-voltage switch cabinet during the power transmission process of the power grid to monitor the surface temperature of the plum blossom contacts of the switch cabinet. After the plum blossom contacts and static contacts inside the switch cabinet are combined, the circuit is turned on, the surface temperature of the plum blossom contacts rises, and the thermoelectric device generates electrical energy under the temperature difference between the surface of the plum blossom contacts and the environment. After passing through the booster, the electrical energy is stored to power the Bluetooth module. The Bluetooth module sends the collected voltage signal to the receiving device. After post-processing, the temperature at both ends of the device is obtained and displayed.

[0081] Example 3 A self-energy temperature and pressure coupling sensing device, specifically comprising the following: This embodiment uses α-MgAg with excellent thermoelectric performance 0.97 Sb 0.99 Thermoelectric devices with a size of 0.8×0.8mm³ were made of Ag2Se-based thermoelectric materials and n-type Ag2Se-based thermoelectric materials, and a single micro-device unit with a size of 6 mm×14 mm×2.5 mm was prepared together with an alumina substrate, Ag electrode, and SAC305 solder. Six units were connected in series to form a self-energy temperature and pressure coupled sensing device.

[0082] A self-energy temperature and pressure coupling sensor device is applied to the bottom of the smart seat. When someone sits down, the temperature difference between the surface of the device and the human body generates electricity. After passing through the booster device, the electricity is stored to power the Bluetooth module. The Bluetooth module sends the collected voltage signal to the receiving device. After post-processing, the temperature at both ends of the device is obtained and displayed, which provides feedback on the sitting time and sitting posture changes of the human body.

[0083] Many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of the present teachings should not be determined with reference to the above description, but rather with reference to the preceding claims and the full scope of equivalents to which such claims are entitled. For the purpose of comprehensiveness, all articles and references, including disclosures of patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the preceding claims is not intended to be a disclaimer of such subject matter, nor should it be considered that the applicants did not consider such subject matter to be part of the disclosed inventive subject matter.

[0084] The above content is a further detailed description of the present application. It cannot be determined that the specific implementation methods of the present application are limited to these. For ordinary technicians in the technical field to which the present application belongs, they can make several simple deductions or substitutions without departing from the concept of the present application, which should be deemed to belong to the scope of protection determined by the submitted claims of the present application.

Claims

1. A self-energy temperature and pressure coupling sensing device, characterized in that: It comprises a thermoelectric device and a circuit board; a plurality of thermoelectric devices are arranged on the circuit board at intervals; The circuit board includes a boost module, a capacitor and a Bluetooth module, the boost module is connected to the capacitor, and the other end of the capacitor is connected to the Bluetooth module; Two ends of the thermoelectric device are connected to wires respectively, and the other ends of the wires are connected to a printed circuit board.

2. A self-energy temperature and pressure coupling sensor device according to claim 1, characterized in that: The material of the thermoelectric device satisfies that the resistivity changes linearly with the temperature in the temperature measurement section, so that the internal resistance of the thermoelectric device is linearly related to the average temperature at both ends of the device, and the open circuit voltage of the thermoelectric device is linearly related to the temperature difference at both ends of the device.

3. A self-energy temperature and pressure coupling sensor device according to claim 1, characterized in that: The thermoelectric device uses p-type and n-type thermoelectric materials.

4. A self-energy temperature and pressure coupling sensor device according to claim 3, characterized in that: The material of the thermoelectric device is one or more of Bi2Te3-based compounds, Ag2Q-based compounds, SnSe-based compounds, Mg2Si-based compounds, MgAgSb-based compounds, MgSiSn-based compounds and Mg3Sb2-based compounds, wherein Q=S, Se or Te.

5. A self-energy temperature and pressure coupling sensor device according to claim 4, characterized in that: The material of the thermoelectric device is n-type Bi2Te 2.7 Se 0.3 and p-type Bi 0.5 Sb 1.5 Te3 material.

6. The self-energy temperature and pressure coupling sensor device according to claim 1, characterized in that: The internal resistance of a single thermoelectric device is below 3Ω.

7. The self-energy temperature and pressure coupling sensing device according to claim 1, characterized in that: The model of the boost module is LTC3108; the model of the Bluetooth module is nRF52832.

8. The self-energy temperature and pressure coupling sensing device according to claim 1, characterized in that: Each of the thermoelectric devices is connected to the circuit board to form a plurality of π-type units.

9. The self-energy temperature and pressure coupling sensing device according to claim 1, characterized in that: There are a plurality of thermoelectric devices, adjacent thermoelectric devices are connected in series, and each thermoelectric device has the same cold and hot ends.

10. The self-energy temperature and pressure coupling sensing device according to claim 1, characterized in that: The circuit board is a printed circuit board; the wire is connected to the circuit board by welding.

11. The self-energy temperature and pressure coupling sensor device according to claim 1, characterized in that: The thermoelectric device is prepared by combining a flexible substrate and rigid particles.

12. A method for preparing a self-energy temperature and pressure coupling sensor device, characterized in that: include: Fix the substrate; Use dispensing or screen printing technology to tin the corresponding position of the substrate electrode; The tin-coated substrate is placed on a positioning base, and a positioning grid is placed on the substrate to sequentially place the p-type and n-type material particles. The upper and lower substrates after the film swinging are attracted by magnetic force and placed in a vacuum eutectic furnace for welding; After welding, cutting is performed to obtain a thermoelectric device; Thermoelectric devices are assembled to obtain a self-energy-collecting temperature and pressure coupled sensing device.

13. The method for preparing a self-energy temperature and pressure coupling sensor device according to claim 12, characterized in that: The preparation method of p-type and n-type material particles comprises: Slice the hot extruded material rods, measure and match the thickness of the sliced ​​p-type and n-type material sheets, and obtain sheets that meet the thickness requirements; The screened sheets are subjected to surface treatments of chemical Ni plating and electroplating of Au layers; The surface treated sheet is pelletized to obtain p- and n-type material particles.

14. The method for preparing a self-energy temperature and pressure coupling sensor device according to claim 13, characterized in that: Thickness measurement and matching of sliced ​​p-type and n-type material sheets, including: The ttv of a single sheet is controlled within 5μm, and the thickness difference between p-type and n-type sheets is within 15μm.

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