Hi.
Usually we charge batterirs with a half sine wave,
all you need to do is to connect a transformer to
your 220v/110v, the output should be up to 3V bigger than
the voltage of the battery.
then you connect a diode, to ensure that the current is
flowing only into the battery.
and after the diode, you connect a resistor, which limit
the current (to about <100mA for aa batteries)

Goodluck
OK