The conductivity of a tubular micro solid oxide fuel cell (TSOFC) anode is measured in-situ. The Ni/YSZ composite anode was fabricated using the electrophoretic deposition (EPD) technique. The four-probe method is used to measure the conductivity of several samples simultaneously under a reducing atmosphere during several cycles of heating, approximate to 100h dwelling and cooling periods. Special attention is paid to maintaining similar fabrication and thermal histories among the samples. Despite all this, the measured conductivities show substantial variation and degradation from sample to sample and from one thermal cycle to the next. The most variations occur during the reduction of the cell, with significant oscillations in the measurements. Sample conductivities exhibit step-like changes during the cooling and heat-up cycles. A theory based on thermal expansion induced Ni particles connection formation and breakage within the YSZ backbone is proposed. Sample electron microscope micrographs are presented showing island-like segregated Ni particles within a continuous YSZ structure. Eliminating such effects not only will reduce the cell performance variability but will also increase the peak power by 60%, according to our simulation results.