The integral method of measuring the Seebeck voltage V(T), in which one end of the sample is held at a fixed temperature TC, and the other end is varied through the temperature T range of interest, has been adapted to short rod-shaped samples. The Seebeck coefficient S is obtained from the slope of the V(T) vs T curve, i.e., S=dV(T)/dT. The apparatus has been completely automated such that the specimen is automatically cycled through a preselected temperature range, up to a maximum temperature of 1000 °C, and the V(T), T, and TC values are acquired, stored, and analyzed by means of a microcomputer. Simplicity of sample handling and minimal operator involvement make this method well suited to the survey of large numbers of samples.

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This work is concerned with the use of the engine start module (ESM) ULTRA 31/900/24V ultracapacitor in specific hybrid systems consisting of a photovoltaic (PV) module, battery, and internal combustion engine (ICE). The test bench research on the ESM cooperating with the photovoltaic module to prevent its self-discharge has been tested, analyzed, and discussed. Moreover, the power distribution between electrochemical batteries and the ultracapacitor is shown. The potential application of the ultracapacitor connected with batteries for the start-up of an ICE engine is also presented. Furthermore, we analyze the possible application of the ultracapacitor plus battery system in heavy transport vehicles and buses. The main advantages and disadvantages of the system consisting of an ultracapacitor and a battery is presented along with the problem of self-discharge and the conditions of ultracapacitor and battery cooperation. This work also features the assumptions made for the conducted tests, selected accordingly for nominal current values of typical starter motors available on the market.

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A high-temperature Hall-effect apparatus is described which allows measurements up to temperatures greater than 1200 K using the van der Pauw method. The apparatus was designed for measurements on refractory materials having high charge carrier concentrations and generally low mobilities. Pressure contacts are applied to the samples. Consequently, special contacting methods, peculiar to a specific sample material, are not required. The apparatus has been semiautomated to facilitate measurements. Results are presented on n- and p-type silicon.