Method of grouping single cells of power sources to build optimal packs using parameters obtained by analysis of impedance spectrum

摘要

A method for selecting unit cells to make an optimal battery pack improves the performance of the battery pack with primary or secondary batteries connected to one another in series, in parallel, or in a combination of them. The method for selecting unit cells to make the optimal battery pack includes measuring the impedance spectrum of the individual unit cells in a predetermined frequency region, fitting the impedance spectrum to an equivalent circuit model composed of parameters including resistance and capacitance components, calculating total resistances from the fitted parameters, and making the battery pack with unit cells of a similar total resistance.