Discharge Characteristics of Lithium-Ion and Nickel-Metal Hydride Batteries by Spontaneous Intermittent Titration Technique.

The galvanostatic intermittent titration technique is a well-known technique for estimating various transport properties of an electrochemical cell. Because of usage of a highly resistive potentiostat, however, no smooth data can be obtained. In the present paper, the spontaneous intermittent titration technique without usage of a potentiostat is proposed and is applied to the commercially available lithium-ion and nickel-metal hydride batteries. It is found that the simple relation V[sub∞], = i(R[subi] + R[subr]) holds during the whole process of discharge, with the internal resistance of a battery (R[subi]) remaining more or less intact. Here, V[sub∞] is the open-circuit voltage of a battery, i is the discharge current, and R[subr] is the external reference resistance. [ABSTRACT FROM AUTHOR]