Seebeck-Coefficient / Resistivity / TEG and Peltier Modules / Thin Films
Seebeck-, Peltier-, and Thomson-Effect
Thermoelectricity describes the mutual influence of temperature and electricity in a material and is based on three basic effects: the Seebeck-effect, the Peltier-effect and the Thomson-effect. The Seebeck-effect was discovered in 1821 by Thomas J. Seebeck, a German physicist, and describes the occurrence of an electric field when applying a temperature gradient in an electrically insulated conductor. The Seebeck coefficient S is defined as the quotient of the negative thermal voltage and the temperature difference and is a purely material-specific variable, which is usually given in the unit μV / K.
Conversely, this effect, called the Peltier-effect, causes a temperature gradient when applying an external current to the conductor. This phenomenon is due to the different energy levels of the conduction bands of the materials involved. Thus, as they pass from one material to another, the charge carriers must either absorb energy in the form of heat, thereby cooling the pad, or they can release energy in the form of heat, thereby heating the pad.
With fossil fuels becoming increasingly scarce and recent global warming gains from rising carbon dioxide emissions, the field of thermoelectricity has returned to public interest because of its effective use of waste heat. The aim is to use the waste heat of heat engines, such as automobiles or conventional power plants, by thermoelectric generators (TEG) to increase their conversion efficiency. But also for cooling applications by means of the Peltier effect, such as the thermostatic temperature-critical components in lasers, efficient thermoelectric materials are of great interest.
The thermoelectric conversion efficiency of a material is usually compared on the basis of the dimensionless figure of merit ZT. It is calculated from the Thermal Conductivity , the Seebeck-Coefficient and the Electrical Conductivity.
To cope with this development, we have developed an instrument for simple and extremely precise material characterization. The Linseis LSR-3 can determine both, the Seebeck-Coefficient and the Electrical Resistivity of a sample in a temperature range from -100°C to +1500°C in a single measurement.
Waste heat recovery
Semiconductors & Sensors
Energy & Power Generation
Measurement and Sample Overview
Below you will find an overview of the different measuring instruments for thermal electric applications. This should serve as an orientation. If you have any questions about a measurement or a material, please feel free to send us a message using the contact form at any time.
Green: measurement is possible
Yellow: measurement is probably possible
Grey: measurement is not possible
|Info||Standard Platform||Harman upgrade for LSR-3||Combined LSR-3 + LFA 1000||Cost efficient, low temp. and Hall Constant||Thin films on Linseis chip|
|Hall Constant / Hall mobility / Charge Carrier|
|Thermal Conductivity||*Please follow note|
|Complete ZT Characterization|
|Temperature range||-100 to +1500°C||-100up to +1500 (Harman -100 up to 300)||-100 up to +1100||-150 up to +600||-170 to +300°C|
|Thinfilm||**Please follow note||***Please follow note|
* Calculated Thermal Conductivity from Harman technique for direct ZT measurement. Harman technique is only applicable for “good thermoelectric samples” from -100°C up to +300°C.
** Seebeck Coefficient and Resistivity of thin films can be measured, but Harman technique for direct ZT and calculated Thermal Conductivity measurements is only applicable to solids, not thin films.
*** Seebeck Coefficient and Resistivity of thin films can be measured, but LFA technique is only applicable to solids and thicker coatings (approx. > 100 µm).
Thermoelectric Overview – Webinar on demand
Take a look at our webinar on instruments for the characterization of thermoelectric materials. Here is a rough overview of the different analysis methods and devices.
Go to Webinar >>