A constant global trend for improving the operating parameters of thermoelectric coolers is the development and search for new technological solutions, as well as the search for new materials.
New materials, including composite materials with high thermal conductivity, for some applications can replace traditional ceramic materials for heat-conducting substrates of Peltier modules. Undoubtedly, this can significantly increase the cooling rate, increase the maximum temperature difference and increase the cooling capacity. This will be especially noticeable if the assembly is built on several pieces of Peltier modules.
However, the main role in increasing the cooling capacity of a thermoelectric cooler has been and still on account of the figure of merit of the thermoelectric material.
The technology for the production of thermoelectric material, bismuth telluride, implemented in the serial production of the Crystal Company, is fundamentally different from the technologies used by other companies. The crystalline structure of the material produced by Crystal consists of many thin plates mated to each other.
It can be compared to a book with many pages. It is possible to bend or twist the book in the same way as it is possible to do with each of the n or p-type elements that we solder inside the Peltier module. Just as the pages of a book will still intact, so our crystals will retain their ability to move heat when an electric current is passed. The cutting process of our unique semiconductor material does not use direct contact mechanical methods. Our fleet of Electrical Discharge Machining, or EDM, in the high purity deionized water allows you to destroy a layer of material near very thin molybdenum wire. The layered structure, where each layer is a crystal with the most optimal structure and the highest thermoelectric parameters, allows us to mass-produce a material with a figure of merit 3.1 K-1 for an n+p compound at a temperature of 300K. Another advantage of using a layered material is its ability to withstand thermal expansion stresses. This allows the use in end devices of PID controllers commercially available from many manufacturers.
The use of such a material for the production of our coolers allowed our team of engineers to create a thermoelectric assembly TA-AA-500-24 with revolutionary performance, packaged in minimal weight and size parameters.
Further improvement of the technology for the production of semiconductor material by the method of controlled crystallization in narrow slots with a thickness H from 0.8mm to 2.4mm (modernized Bridgman method), as well as the development of the technology of crystallization and splicing by the plastic deformation (Bridgman Anvil) method of ingots with a thickness of 0.5mm with an even more perfect crystal structure into blocks up to 3mm thick, will allow, according to our forecasts, for the foreseeable future to start production of thermoelectric material with a figure of merit 3.25 K-1 for n+p bones at a temperature of 300K.