To extend lifetime of LiFePO4, the general recommendation is to never discharge below ~10% or charge above ~90%, but the impact of those two distinct events cannot be equally damaging.
So which will result in faster cycle life degradation:
-never discharging below 10% but charging to 100% (3.65V/cell) [top-balanced battery]
-never charging above 90% but discharging to 0% (2.5V) [bottom-balanced]
Also, since the cells are rated for 2500 to 3500 cycles from 0% (2.5V) to 100% (3.65V) before capacity has degraded to 80% of initial rated capacity, this should mean that cycling between 0% to 80% of rated capacity is guaranteed to deliver over 2500 to 3500 cycles which brings up a second question: will there be any significant difference in lifetime between:
-discharging to 0% (2.5V) but only charging to 80% (~3.325V)
[should be well over 2500 to 3500 cycles before charging needs to continue to 3.65V to charge a full 80% of initial rated capacity
-only discharging to 10% (3.0V) but charging to 90% (~3.35V)
[should also be well over 2500 to 3500 cycles before discharge needs to continue to 2.5V in order to charge a full 80% of initial rated capacity by 3.65V]
So which will result in faster cycle life degradation:
-never discharging below 10% but charging to 100% (3.65V/cell) [top-balanced battery]
-never charging above 90% but discharging to 0% (2.5V) [bottom-balanced]
Also, since the cells are rated for 2500 to 3500 cycles from 0% (2.5V) to 100% (3.65V) before capacity has degraded to 80% of initial rated capacity, this should mean that cycling between 0% to 80% of rated capacity is guaranteed to deliver over 2500 to 3500 cycles which brings up a second question: will there be any significant difference in lifetime between:
-discharging to 0% (2.5V) but only charging to 80% (~3.325V)
[should be well over 2500 to 3500 cycles before charging needs to continue to 3.65V to charge a full 80% of initial rated capacity
-only discharging to 10% (3.0V) but charging to 90% (~3.35V)
[should also be well over 2500 to 3500 cycles before discharge needs to continue to 2.5V in order to charge a full 80% of initial rated capacity by 3.65V]