Dimensional analysis of round cell discharge characteristics: I - Development of an adaptive reserve-time prediction algorithm.

The result of an investigation performed for the purpose of developing an adaptive state-of-charge indicator for use in estimating reserve-time during a battery discharge are discussed in this memorandum. A dimensional analysis on the discharge characteristics of List 15 Round Cells in the useful range of discharge currents lead to the identification of the relevant physical variables and constants needed to describe the discharge behavior quantitatively. This analysis provided the basis for the proposed algorithm which involves analyzing actual discharge behavior in real-time and modifying the estimation of available reserve-time accordingly. The propose algorithm was tested with actual discharge data from constant current and variable current discharges.