Fabrication of a transversal multilayer thermoelectric generator with substituted calcium manganite

Abstract

The sintering behavior and thermoelectric performance of Ca0.99Gd0.01Mn0.99W0.01O3 was studied, and a multilayer thermoelectric generator was fabricated. The addition of CuO as sintering additive was found to be effective for the reduction in the sintering temperature from 1300°C to about 1000°C-1050°C. Dense samples were obtained after firing at 1050°C, whereas some porosity remained after firing at 1000°C. Samples sintered at reduced temperature exhibit lower electrical conductivity, whereas the Seebeck coefficient S = −150 μV/K at 100°C is not affected by lowering the sintering temperature. The figure of merit is ZT = 0.12 at 700°C for samples sintered at 1300°C; ZT = 0.08 and 0.03 were obtained for multilayer laminates sintered at 1050°C and 1000°C, respectively. A transversal multilayer thermoelectric generator (TMLTEG) was built by stacking layers of substituted CaMnO3 green tapes, and printing AgPd conductor stripes onto the thermoelectric layers at an angle of 30° relative to the direction of the heat flow. The multilayer stack was co-fired at 1000°C. The TMLTEG has a power output of 2.5 mW at ∆T= 200 K in the temperature interval of 25°C-300°C. A meander-like generator with larger power output comprising six TMTEGs is also presented

Regulating Multiscale Defects to Enhance the Thermoelectric Performance of Ca0.87Ag0.1Dy0.03MnO3 Ceramics

“…It is well known that the origin of the high Seebeck coefficient was due to the energy filtering of low-energy carriers by low-energy defects associated with the decrement of oxygen defect concentration. 26 Along with the low electrical resistivities and the large Seebeck coefficients, the power factors (PFs) are exhibited in Figure 9c. With the increasing measured temperatures, the power factors of all samples increased firstly and then decreased, and the peaks located in between 400 and 500 °C.…”

“…It can be inferred that the enhancement of S value took place with the reduction of the concentration of charge carrier and the increment of m DOS * 3/2 . It is well known that the origin of the high Seebeck coefficient was due to the energy filtering of low-energy carriers by low-energy defects associated with the decrement of oxygen defect concentration . Along with the low electrical resistivities and the large Seebeck coefficients, the power factors (PF s ) are exhibited in Figure c.…”

Geometrical Optimization and Transverse Thermoelectric Performances of Fe/Bi2Te2.7Se0.3 Artificially Tilted Multilayer Thermoelectric Devices

“…Second, the related transverse TE device is single-leg, and no electrode required. It can be cut into a variety of shapes, such as tubes, sheets, thin film, trapezoid, and cone, to fit the demand of infinite-stage cascade power generator or cooler [18][19][20]. Third, the dependence of V x on the length to height ratio is greatly beneficial in developing the micro/nano-scaled devices.…”

Glass‐ceramic composites as insulation material for thermoelectric oxide multilayer generators

“…5,6 For co-fired generators from CaMnO 3 and Ca 3 Co 4 O 9 , the sintering temperature is limited to 900 • C due to the phase stability of Ca 3 Co 4 O 9 . The combination of pressure-assisted sintering 7 and sintering additives 8 provides the theoretical possibility of co-sintering these two material systems in one single step.…”