Disclosed is a battery cell having positive and negative terminals penetrating the same end of the cell, and equalized internal resistance through all paths connecting electrode modules with the terminals. The equalized resistances insure uniform aging of electrode pairs, thus maximizing the life of the battery. A single equalizing busbar is inserted between the equalized terminal, which can be either the negative or the positive terminal, and that end of the equalized busbar remote from the terminaled end of the cell. The length and linear resistance increment of the equalizing busbar are independent of corresponding parameters for the equalized and non-equalized busbars. The resistance increment between any two adjacent electrode connections along each of the equalized and non-equalized busbars must be the same. A simple way to satisfy this condition is to make the length and linear resistance increment of the equalized and non-equalized busbars substantially equal.