A method for providing an elective replacement indicator (ERI) voltage for a first implantable electrochemical cell, comprising the steps of providing a second, substantially identical exemplary electrochemical cell; repeatedly connecting and disconnecting the second cell to a sequence of at least three loads, thereby discharging the second cell from a state of about zero percent to at least about ninety percent depth-of-discharge; generating cell voltage vs. depth-of-discharge plots for the at least three loads repeatedly connected to the second cell; identifying a range of depth-of-discharge for the at least three loads wherein a statistical indicator of the second cell voltage variability with load at the same depth-of-discharge is less than a predetermined value among the at least three loads; and then defining the ERI voltage for the first implantable electrochemical cell as the voltage that occurs at a predetermined load at a specified point within the identified range for the second electrochemical cell.