No. 4-AA batteries hooked together is a much smaller package than the 6 volt lantern battery.
9v! More voltage, more strength! Many 9v batteries merely have 1.5Volt cells jammed together to make 9V!
Yes, if the two 6 volt batteries were connected together in series.
No.
lithium-ion battery
Two 6 volt batteries in series, yes. In parallel, no.
The charger needs to be set to charge for the voltage that the battery is designed to produce. Most car batteries are 12 volt batteries.
use two 12 volt batteries in series.
They make a 7.5 volt battery when put together
A 3 volt battery is a battery that produces 3 volts. Many watch batteries produce 3 volts.
If you have two 6 volt batteries you can take a jumper wire and connect the negative post on one battery to the positive post on the other battery then connect the remaining pos and neg posts to the 12 volt battery charger.
To get 24 volts from two 12 volt batteries, hook the positive post from one battery to the negative post of the other.
All auto batteries are 12 volt except very old cars prior to the late 50s.