Difference Between Batteries Wired in Series and Wired in Parallel

Question:

How to hook up two house batterys. The diagram on your site shows two different ways of hooking the batteries up mine look like the one on the left with the one wire in the middle of connecting both batteries can you tell me if its ok to hook the middle wire one end to positive and the of the end to the negative negative? I was told negative to negative and positive to positive but the diagram shows the middle wire shows positive to negative is that OK?

asked by: Joseph

Expert Reply:

There are two different ways of hooking up your 12 volt batteries, and what you are describing, with the batteries being connected one end to positive and one end to negative is called being wired in series and yes, this is okay.

What this will do is make the output of your two 12 volt batteries be 24 volts. To do this, the negative on one battery is wired to ground, you wire the positive of that battery to the negative of the second battery, and the positive is the 24 volt output.

The other way, wiring in parallel, will give you a longer battery life but still have a 12 volt output. To do this you will wire the negative to negative for the ground and positive to positive.

So you can do either way, it just depends on if you want a 24 volt output (wired in series) or 12 volt output with more capacity (wired in parallel).

Either way it is important that you use a battery charger to ensure your batteries work continually, the CTEK MULTI US 7002 12-Volt Universal Battery Charger w/ Pulse Maintenance and Backup Power # CTEK56353 which will charge batteries that have capacities between 14 amp hours and 150 amp hours.

I have added a links to a video review of the charger for you to check out as well.

expert reply by: Kyle S