It you set the output to 5v, it should be able to transfer some of the remaining AA charge into the LiPo. Just don't connect it at the same time as the USB.
Is this a precaution because of energy flowing back into the extra device or the LiPo circuit itself? I believe we've discussed elsewhere that you can have both multiple inputs as long you have the appropriate diodes in place for back flow.
Also, after speaking with the developer of the AASaver, he suggested that limiting the LiPo circuit to 100mA would be more efficient while transferring whatever juice is left in the AA/AAAs. Any insight into this? I planned on wiring in the additional 1000ohm resistor to bump the charging circuit up to 1000mA from 500mA.
Yes, I'm a real person.