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Battery bank assembly; amp hour calculation

This article is designed to give basic information on how to connect batteries together in a bank and then to calculate the amp hour capacity of the bank.

Product Line:
All devices requiriing battery banks

All units with external battery banks

1. two batteries can be connected in either "series" or in "parallel".
1a. "series" is when we connect the battery poles in a positive to negative orientation.
1a. when in series we add the voltage and average the amps
1b. "parallel" is when we connect the battery poles in a positvie to positive and negative to negative orientation.
1b. when in parallel we add the amperage and average the volts

eg. when taking two 6 volt, 100 amp hour batteries in series, it becomes 100 amps at 12 volts. When in parallel, it becomes 200 amps at 6 volts.

eg. if you have six 120 amp hour batteries at 12 volts each, you end up with a 12 volt system with 720 amp hours (Ah) assuming that you connect the batteries in parallel. If you hook them up in series-parallel you will end up with a 24 volt system with 360Ah.

Series-parallel bank assembly means that we take two batteries and connect them in series and then assemble them in parallel with another series pair. This is normally done in a mobile application to bring 6 volt batteries up to a 12 volt system. Sometimes to bring 12 volt batteries up to a 24 volt system. It is not restricted to pairs of batteries in series but this is most typical.

Battery bank assembly is considered a very basic skill set in this field. As such, there are very few articles detailing how to do this or how to calculate them.
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