How do I increase the capacity of my battery and system?

Your individual batteries capacity can not be increased from its original capacity. However, strings of batteries can be easily connected together to increase a systems voltage and / or its capacity.

To increase the voltage of a system you must connect multiple batteries in Series. To increase a systems capacity (amp hours, reserve capacity etc.) connect multiple batteries in Parallel. To increase both the systems voltage and the capacity, connect multiple batteries in Series and in parallel.

If more capacity is required, as mentioned above multiple batteries can be connected in parallel (positive terminal of Battery One to the positive terminal of Battery Two and so on). Only new and identical batteries should be used. If you connect two 12-volt batteries in parallel and they are identical in type, age and capacity, you can potentially double you original capacity. If you connect two that are not the same type, you will either overcharge the smaller of the two, or you will undercharge the larger of the two. If you connect two identical – but one older – you will definitely reduce the life of the new one. When connecting in series or parallel and to prevent recharging problems, do not mix old and new batteries or ones of different types. Cable lengths should be kept short and cable must be sized large enough to prevent significant voltage drops. There should be a maximum of 0.2 volts (200 milli-volts) or less drop between batteries.

An excellent and easy to understand free booklet on multi-battery applications, “Introduction to Batteries and Charging Systems”, can be downloaded from http://www.surepower.com.