When carrying out field works with Self-Potential (SP) and Induced Polarization (IP) methods, it is necessary to measure small values of the electric field; therefore, non-polarizable electrodes are used. However, for measurements in boreholes, the use of non-polarizable electrodes is technologically inconvenient. In this work, we performed systematic series of PS measurements, in order to study the stability of polarizable lead electrodes in a borehole. We present results of monitoring of voltage between two electrodes in a probe submerged in a hydrogeological borehole with fresh water (~ 0.05 S/m). Repeating measurements separated by several days show that when the electrodes were not moved, their average drift does not exceed 0.5 mV/day. Voltage of unclear nature occurs when the electrodes were moved along the borehole, with a drift of about 13 mV when the probe is lifted by 2 meters, which significantly complicates the operational SP measurements. Relaxation to a stable level takes about 15 minutes. However, the variation interval of the potential is relatively acceptable enough to measure IP with a pulse duration of several seconds, since modern equipment offers the possibility of compensating not only the linear voltage drift, but also the second-order drift.