Here is the charge/discharge curve for standard nokia bl-5c li-ion battery
in terms of relative capacity vs. cell voltage. The cell is 850 mAh rated
(but something like 800 mAh is available). The charging is standard CC-CV
procedure with 800 mA CC mode current ( about 1C) and 4.105V threshold.
Discharge is with constant current 100 mA (so about C/8) and 3.5 V cutoff.
Hope this will be handy for someone.

Marcin