Batttery Connections

Series and Parallel connections

To begin with we will discuss the ways in which you can connect two cells together.

NOTE: Only cells of the same type should be connected together; they should be made by the same manufacturer, be the same age, have the same voltage and the same capacity.

Let us assume that the voltage of an individual cells described below is 1.5v each with a capacitance of 2700mAh.

Serial connection

With series connection, the total voltage of the pack will be the sum of the individual cell voltages. The overall capacitance of the cells remain the same, so for the configuration above:

Total Voltage = 1.5 + 1.5 = 3v

Total Capacitance = 2700mAh

Parallel connection

With parallel connection, the total voltage will remain the same as that of an individual cell. It is the capacitance which changes, increasing with each battery added to the arrangement so that the total capacitance of the pack becomes the sum of the individual cell capacities:

Total Voltage = 1.5v

Total Capacitance = 2700 + 2700 = 5400mAh
= 5.4Ah

Combined Series/Parallel connections

It is common, especially when the power requirements of a device become relatively large. There are many ways to connect a group of batteries in both series and parallel within the same pack. This increases the range of voltage and capacity characteristics that can be provided by such packs. There are many different ways in which these connections can be made; how this is done will not only depend on the power requirements of the device, but also the space requirements of the application.

Because of this, there are numerous ways in which batteries can be arranged; not only the connections between the batteries can vary, the way in which the batteries are arranged can also vary.