Battery Connections: Series vs. Parallel

It does not matter if you are running a 12 Volt, 24 Volt or 48 Volt system. You have probably had a conversation with someone about your battery bank. The main question that people always ask is do you keep your batteries in Parallel or Series? For those who might not understand these terms, let me explain them for you. Batteries in Parallel, means that the batteries in your bank are connected so that the inverter thinks they are all one big battery. Meaning if you connect four batteries 12V in parallel your inverter, still sees one 12 volt battery. Your power source is still 12 volts and your amp hours are quadrupled. Batteries in Series, means that the batteries in your bank are connected in a way that the volts are doubled, for each series of batteries. To keep this simple, two 6 volt batteries in “series” are 12 volts. The power inverter recognizes them as a 12 volt power supply. Now that we have a basic understanding of series and parallel. Your next question is probably which one is the better connection? Well, that depends on your system. How many batteries are in your bank? What voltage are they? Most battery manufactures recommend no more then 4 batteries be connected in parallel. One point I would like to share is that if your batteries are in parallel, and one of them fails, the whole bank might stop putting out power. If the batteries are in series, if one battery fails, then just that “cell” or group of series batteries will stop producing power. So if you have a large battery bank, series is definitely the way to go.