A Study of Capacity Fade in Cylindrical and Prismatic Lithium-Ion Batteries

Identical electrodes wound in both a cylindrical and a prismatic configuration provided different capacity fade rates. At the completion of 300 cycles with a C/2 charge and IC discharge, the prismatic cells faded 24% and the cylindrical cells faded 16%. In the cylindrical-type cell, the fade was primarily caused by a reduction in the capacity of the cathode. The higher fade rate in the prismatic cell was attributed to lower cell stack pressure which resulted in more anode swelling during cycling. The increased porosity of the anode in this cell reduced the integrity of the electrical conduction network causing many graphite particles to become isolated or less accessible.