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Battery bank assembly; amp hour calculation

Issue:
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

Environment:
All units with external battery banks

Resolution:
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.

Cause:
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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