Hello,

I have a AA battery case with two batteries in series. Each one outputs 3.7v.

Can I substitute a single 7.4v battery and place it on one side of the battery pack. Assume amps are the same ?

 

Generally, yes.

 

Usually batteries are rated in mA-Hours or Amp-hours. You can replace with smaller or larger with either reduced or increased run-time. Battery chemistry determines the charging profile.

 

to follow-up, am i correct that in one battery slot I can make a dummy battery that has a wire running through it, that connects the pos and neg terminals and the other that just connects the terminal ends (pos & neg) that come from the power source (no wire running through it)?

 

Yes, you can also short the unused side with a wire jumper.

 

Which type of Batteries gives 3.7 Volts with 2 in series?

 

18350 li ion

 

18350 li ion

Another input to my learning. Thanks.