Hmmmm. I'm not sure. This from Martin, November 2006
Tesla Motors - thinkThere is a huge difference in cycle life between a 4.2V/cell charge (defined by the manufacturers as “fully charged”) and a 4.15V/cell charge. 4.15 volts represents a charge of about 95 percent. For this reduction of initial capacity (5 percent), the batteries last a whole lot longer. Unfortunately, further reduction of charge has a much smaller benefit on cycle life.
Understanding this tradeoff, Tesla Motors has decided to limit the maximum charge of its cells to 4.15 volts, taking an initial 5 percent range hit to maximize lifetime of the pack. We also limit discharge of our battery pack to 3.0V/cell and will shut down the car when the batteries reach this level. Limiting our charge rate is less of a compromise, since the wire size and availability of very high current outlets limit us much more than the batteries do at this point.
If I understand this correctly, there is a limit on the benefit gained by reducing the depth of discharge. You reduce the maximum range but batteries don't last significantly longer than they would normally.
So you might as well run larger capacity cells at the same old 95% setting - what Tesla refers to as "Max".
Presumably other factors like average battery pack temperature have a greater impact but are harder to deal with since energy is required to reduce the temperature below ambient.