I have a system that uses an Arduino Uno board as a "brain". All the elements in the system are powered by a single Li-po battery (3-cell, 11.1 V, 1800 mAh).
I made a circuit so the Arduino can check the battery voltage and decide when it needs to recharge. I also have a circuit that controls the battery charge sequence and interrupts the power when the battery is charged, sending a signal to the Arduino interrupting its power saving mode. The Arduino enters the power saving mode when the charging sequence is initiated. The charging circuit uses 12 V and 450 mA which I plan to supply with a 12 V, 6 W solar panel.
My question is: can I charge the battery while the Arduino is still on, but in power saving mode?
If not, how can I make this system self-charging while keeping the Arduino on continuously?