Help on intelligent battery charger for emergency

[Booleano]

Hi all,

I've searched around the forum but didn't find the right answer to my question.
I've to design a charging system with the following requirements:

Vin - 6V-30V (600mA – 1A )
Support for battery packs 3.6V, 6V, 12V, 24V – Nimh, NiCd

The circuit should normally charge the battery pack, when powered through AC/DC line - the power module is already available

When the main power is disconnected, the lamp should be battery powered,
and should be turned off when Vbatt falls below 2.7V (for a 3.6V battery pack).


I've found a lot of example with different microcontroller but I've some questions...
1) should it be possible to support all the above battery voltages with the same hardware? without carryng out any modification to the circuit?
As i think the best choice would be a buck converter, do i have to calculate different values for inductor and capacitor for a different battery pack?
2) How i can monitor the voltage to for 2.7V in a realiable way?


I would appreciate any help from the forum.

many many thanks

B.