Let me state the obvious here, LiFe's are different than Li-ion's and LiPoly batteries but are charged in the same manner (CC then CV), just the voltage levels are different. There doesn't seem to be a Off the shelf IC that can charge these batteries, as they require a final voltage of 3.6 to 3.8v. The ones I just bought need a final voltage of 3.6v to finish charging.
For a while, Ive successfully used a Standard Li IC to charge smaller capacity LiFe batteries that needed 3.8V, I just used a Schottky diode to drop the extra voltage (and ofc checked the voltage manually each hr). But since a regular Li battery stops charging at 4.2v, These new Batteries need 3.6v EOC. Can I still use the Same Diode Drop concept to successfully charge the Batteries? Are there any downsides to doing this? Finally, Is there a Easier way to do this since the charger I am using wasnt specially made for LiFe batteries?
Ive seen the popular LM317 Circuit, and LiFe batteries are more rugged than Li-Ion and have thought of using that, the only downside is that it doesnt shut off when the batteries reach their full charge. Ive thought about using a Current sense amp to do this, feed it through a comparator and then a FET to shut the input off once it reaches final charge, but Im unsure if this method will work
(side note: There Is one Charger IC available but its in a QFN or smaller package-impossible for me to solder)