A system for estimating physical parameter(s) of a medium having electrolyte(s), including at least one working electrode; one counter electrode; a current generator delivering to the electrodes electric current pulses; a computer-readable memory including a predefined analytic model of an electric potential, between the working and counter electrodes, as a function of time, receiving as inputs the current and current pulse duration and including the physical parameter to be estimated; an acquisition unit including a signal amplifier for acquiring and amplifying an electric potential recorded by the electrodes; a processor including a stimulation module controlling the current generator to deliver a biphasic charge-balanced current during a stimulation duration; an acquisition module acquiring an electric potential variation during the stimulation duration; and a calculation module receiving the acquired electric potential variation, fitting the acquired electric potential variation using the predefined analytic model, and outputting the estimated physical parameter.