Computer simulation evaluation of the geometrical parameters affecting the performance of two dimensional interdigitated batteries

Abstract

The effect of the geometrical parameters of interdigitated batteries, including the number, thickness and the length of the digits, on battery delivered capacity was investigated in order to optimize battery performance. This optimization was carried out in two dimensions maintaining constant the area of the different components and based on the Doyle/Fuller/Newman theoretical model that describes the electrochemical and ionic transport processes within separator and electrodes. It is observed that the delivered capacity of the battery increases with increasing the number of digits as well as by increasing the thickness and the length of the digits, which is related to the smaller path for lithium ion movement during the intercalation/deintercalation processes. Thus, an optimized interdigitated geometry with eight digits shows a delivered capacity of 323 Ah.m-2 at 350C in comparison with 0.7 Ah.m-2 for a conventional geometry.