In some specified applications, the main method is to use a special high thermal conductive epoxy resin binder. Since the coefficients of thermal expansion of the ceramics of TECs, heat sink and the cooled object, it's not recommended to use epoxy resin binder in large TECs. The detailed steps are as follows:(more)

When a material is melting, it will absorb the heat from the hot end of thermopile in the isothermal condition. The isothermal characteristic is the necessary condition of maintaining the cold end constant. The time for the melting stage is the temperature constant time of the cold end.(more)

CPU of computer is a high density heating element. Based on the cooling principle of thermoelectric cooler (TEC), the cold end of TEC is in contact with the display chip and the hot end is in contact with the heat sink. When connecting a power supply, the temperature difference of the cold and hot end will come out and moves from the cold end to the hot end through lattice energy. Only if the hot end heat can be dissipated effectively, the cold end will be cooling constantly and the cooling effect will be pretty good. In fact, TEC is a heat pump, which can transfer the heat from chips to heat sinks, so only if the heat of the TEC hot end is being dissipated continually, the cold end can be cooling and the display chips can be in a relatively constant temperature state. However, in the hot end of TEC, the heat sink and fan are still needed. In the process of using TEC, there are some other points to consider.(more)

The material figure of merit Z is an important parameter to measure the cooling capacity of TEC and its expression is. In order to improve Z value, conductivity σ and Seebeck coefficient α should be improved and thermal conductivity λ should be reduced. λ consists of phonon thermal conductivity λp (about 90%) and electronic conductivity λe. These three parameters are not independent of each other, which all are the function of carrier concentration n and temperature T. In the condition of different environment temperature, the value of Z is different. In general, the dimensionless factor ZT is used to describe material’s performance. Bi2Te3 is the most widely used thermoelectric material and the value of ZT can be up to 0.9. However, the cooling efficiency of TEC made by Bi2Te3is only 30% of compression refrigeration.(more)

Thermoelectric cooler is like a heat pump when it's working, transferring heat from one point to another. This is not a common heat absorption process or a magic heat consumption process. When it's powered on, one end of the TEC module will become cold while the other end hot. The cooled down end transfers the heat to the hot end, which conforms to the thermodynamics law. In order to complete a heat transfer process, the thermoelectric cooler needs to be connected to a proper heat sink, which is used to release the heat from the cold end and produced during the operation of the components.(more)

Based on the “thermoelectric effect”, a thermoelectric generator (TEG) converts heat directly into electricity. Because of no moving parts, it is very silent and highly reliable.(more)

Until 1950’s, with the rapid development of semiconductor thermoelectric mateials with good performances, the efficiency of thermoelectric effect was improved so greatly that the thermoelectric refrigeration and the thermoelectric generation entered into the field of engineering practice. When comparing with the existing compression refrigeration or absorption refrigeration, the thermoelectric cooler (TEC) depends on the heat transfered by electrons to achieve refrigeration. It has the following advantages:(more)

Although thermoelectric cooling technology has been developed very fast, there are still many problems that need resolution. Because of the material constraints, the cooling capacity of thermoelectric cooler (TEC) is limited and its cooling efficiency is too low. With the increase of the required temperature difference, the more the TEC series is, the lower the cooling efficiency is. So TEC cannot completely replace the traditional cooling technology, which can only be used in the small cooling capacity field. Only if the cooling capacity is improved, TEC can get more extensive application. The key is that better materials should be developed based on the cooling principle of TEC.(more)

In the ion conduction type conductor, the carrier may be positive ion or negative ion. In the electronic conduction type conductor, carrier is electron and current can be formed by electron movement. With the increasing of carrier concentration, thermoelectric coefficient α will reduce and thermal conductivity σ will increase. In the thermal coefficientλ, the lattice thermal conductivity λP (about 90%) is irrelevant to the carrier concentration, while the electron thermal conductivity λe is proportional to the carrier concentration. So the appropriate carrier concentration n is selected to make get the maximum difference. Figure of merit z and other three parameters α, ρ, λ have a certain relationship with carrier concentration n. When n is close to 1019cm-3, the value of Z can be the maximum.(more)

In practical application, the thermoelectric modules are often placed inside of devices, and even they can be directly combined with devices needing refrigeration into a whole. For example, in optical application, the thermoelectric module can be a part of a detector or diode; in a semiconductor device, it can become a whole with the ceramic package. This lays the foundation for developing composite materials with temperature control-structure integration or even intelligent temperature control composite materials.(more)