Outback Power Systems EnergyCell RE Battery Owners Manual - Manual (Page 10)

Installation and Operation
10 900-0127-01-00 Rev D
Figure 8 Series/Parallel String Configurations
Load Bus – Load Bus +
Load Bus –
Load Bus +
Batteries are placed in both series and parallel for both additive voltage and amp-hour capacity.
Series strings placed in parallel have the same nominal voltage as each string. They have the same
amp-hour capacity of each string added together. Two parallel strings of two EnergyCell batteries in
series have a nominal voltage of 24 Vdc, twice the nominal voltage. They also have double the amp-hour
capacity of a single battery. Two parallel strings of four batteries in series have a nominal voltage of
48 Vdc at double the amp-hour capacity of a single battery.
In a series-parallel bank, it is not recommended to connect the load to the positive and negative
terminals of a single string. Due to cable resistance, this will tend to put more wear on that string.
Instead, it is recommended to use “reverse-return” or “cross-corner” wiring, where the positive cable is
connected to the first string and the negative is connected to the last. This will allow current to flow
evenly among all strings.