Cycle life estimation of lithium secondary battery by extrapolation methodand accelerated aging test

The testing methods to estimate the Life cycles of lithium ion batteries fo r a short period, have been developed using a commercialized cell with LiCo O2/hard carbon cell system. The degradation reactions with increasing cycle s were suggested to occur predominantly above 4 V from the results of opera ting voltage range divided tests. In the case of the extrapolation method u sing limited cycle data, the straight Line approximation was useful as the cycle performance has the linearity, but the error is at most 40% in using the initial short cycle data. In the case of the accelerated aging tests us ing the following stress factors, the charge and/or discharge rate, large a ccelerated coefficients were obtained in the high charge rate and the high temperature thermal stress. (C) 2001 Elsevier Science B.V. All rights reser ved.