Yes, In series connection with -ve to +ve for each terminals or vice versa.
e.g. suppose the batteries are like -Battery1+
Connect them as (-Battery1+)+(-Battery2+)+(-Battery3+)+(-Battery4+) will give you 48 Volts.
You will have a 12 Volt source with double the charge capacity.
depends on the voltage of the batteries.. four 12 volt car batteries would output 4x12 = 48 v
Connect two 12 volt batteries in series and you will have an output of 24 volts.
join two 6 vault battaries two make 12 vaults
That is Impossible. You can however make two 6 volt batteries into a 12 volt system by wiring the two 6 volts batteries in Series. You will then have an output voltage of 12 volts but the amperes will only be what one of the batteries have, In other words the volts will double but the amps will stay the same as if you only had 1 battery connected.
how Can you charge multiple 12 volt batteries with a car?
You cannot use a 12 volt charger to charge 2.6 volt batteries. The 2.6 volt batteries will become hot, very quickly, and explode.
Don't know what your intentions are but the 6 - 6 volt batteries would probably deliver more amps. ======================================= -- If the batteries are connected in series, six 6's are exactly equivalent to three 12's. -- If they're operated in parallel, then the terminal voltage of six 6-volt batteries is still just 6 volts. There's no way to connect 12-volt batteries and make them look like 6-volt units in parallel. It's really important to find out exactly how the original 6-volt batteries are connected in the device. 1). They may be all in parallel, giving an output of 6 volts. 2). They may be all in series, giving an output of 36 volts. 3). They may be connected in three parallel branches of two series units each, for an output of 12 volts. 4). They may be connected in two parallel branches of three series units each, for an output of 18 volts. If you know what you're doing, you can replace them with 12-volt units in cases 2). and 3)., but not in cases 1). or 4).
Depends on the battery size. If your boat is a 12 volt system and you wire two 12 volt batteries in series you then have 24 volts. If the batteries are 6 volt batteries you will be fine. If you have a 12 volt system on your boat and want to use two batteries then wire two 12 volt batteries in parallel. You will still have 12 volts but will have double the amperage available and this will extend the running time of the batteries.
you only need two 12 volt batteries to make 24 volt. connect them in series
That would depend how they are connected. Are all Eight 6 volt batteries connected in series giving a total output voltage of 48V. Or are they connected with 2 sets of 4 batteries in parallel then connected in series to give a 24V output.
No!