A method of standardizing a battery encasement of at least two batteries having differing battery characteristic combinations for use in implantable medical devices, the battery characteristic combinations comprised of current delivery capability, voltage delivery capability, and energy capacity, the batteries each having an electrode assembly comprising at least one anode and one cathode and a separator interposed therebetween, the method comprising: providing first electrode assemblies having a first dimension corresponding to a first battery characteristic combination of energy capacity, current delivery capability, and voltage delivery capability, a first electrode assembly comprising a stack of a first number of anode and cathode plates; providing battery cases having a common configuration defining an electrode cavity for securely accommodating said first electrode assembly; providing second electrode assemblies having a second dimension, less by a given amount from said first dimension, corresponding to a second battery characteristic combination of energy capacity, current delivery capability, and voltage delivery capability, said second battery characteristic combination differing from said first battery characteristic combination, a second electrode assembly comprising a stack of a second number of anode and cathode plates; disposing individual ones of said first electrode assemblies respectively into said electrode cavities of individual ones of said battery cases to produce a first battery type wherein the battery case forms a battery terminal; and incorporating an inert insert into individual ones of said second electrode assemblies and disposing said individual ones of said second electrode assemblies incorporating an inert insert respectively into said electrode cavities of other individual ones of said battery cases and to produce a second battery type, wherein the battery case forms a battery terminal, said inert spacer being dimensioned to compensate for said given amount to securely accommodate said second electrode assemblies in said electrode cavities of said other individual ones of said battery cases. providing first electrode assemblies having a first dimension corresponding to a first battery characteristic combination of energy capacity, current delivery capability, and voltage delivery capability, a first electrode assembly comprising a stack of a first number of anode and cathode plates; providing battery cases having a common configuration defining an electrode cavity for securely accommodating said first electrode assembly; providing second electrode assemblies having a second dimension, less by a given amount from said first dimension, corresponding to a second battery characteristic combination of energy capacity, current delivery capability, and voltage delivery capability, said second battery characteristic combination differing from said first battery characteristic combination, a second electrode assembly comprising a stack of a second number of anode and cathode plates; disposing individual ones of said first electrode assemblies respectively into said electrode cavities of individual ones of said battery cases to produce a first battery type wherein the battery case forms a battery terminal; and incorporating an inert insert into individual ones of said second electrode assemblies and disposing said individual ones of said second electrode assemblies incorporating an inert insert respectively into said electrode cavities of other individual ones of said battery cases and to produce a second battery type, wherein the battery case forms a battery terminal, said inert spacer being dimensioned to compensate for said given amount to securely accommodate said second electrode assemblies in said electrode cavities of said other individual ones of said battery cases.