Comparison Study of the Physical Characteristics and Cycling Performance of Commercially Available Li-Ion Batteries

Abstract

Based on the recently published data of Johnson and White [1] a number of relevant specific characteristics of commercially available Li-ion batteries of five leading Japanese companies are derived and an attempt is made to disclose their impact on their cycling performance. Four of the cells, those of Sony, Moli, A&T, Sanyo, are of the 18650 size, and one of Matsushita is of the 17500 size. The batteries are similar in cathode material (LiCoO₂), electrolyte composition (EC based solvent with 1 M LiPF₆), separator materials (micro-porous PE and PP sheets), and current collectors (Al and Cu foils). However, the electrodes and batteries differ in many important specific characteristics. Before disclosing them, it is necessary to remind some useful relations.