Harnessing the Power: Series and Parallel Stacking of Batteries

Stacking batteries in series or parallel configurations offers customized power solutions for devices. This guide explains the intricacies and safety precautions of harnessing battery power.


As budding electricians, we’ve explored the fascinating world of batteries, understanding their workings, components, and the various types available. However, there are scenarios where a single battery cannot meet the power requirements. It’s in these situations that we stack batteries together, either in series, in parallel, or a combination of both. Doing so alters the total voltage and current, allowing us to customize the power output. In this article, we will delve into the intricacies of series and parallel stacking of batteries.

example of battery stacking in series and in parallel
Source- https://fifthaveinternetgarage.blogspot.com/2019/05/series-vs-parallel-battery.html

Series Stacking

When we say batteries are connected in series, we mean they are arranged end-to-end. Such that the positive terminal of one battery connects to the negative terminal of the next.

When batteries connect in this way, the total voltage of the system is the sum of the voltages of each battery. For instance, if you connect two 1.5V AA batteries in series, the total voltage supplied to the circuit is 3V (1.5V + 1.5V).

However, the current (measured in amperes) remains the same as that of a single battery. This configuration is often used when a higher voltage is needed. Such as in a flashlight or a battery-operated toy car.

Parallel Stacking

In a parallel connection, all the positive terminals of the batteries connect together. And all the negative terminals connect together.

Unlike series connection, in a parallel connection, the voltage remains the same as a single battery. But the total current supplied to the circuit is the sum of the currents of each battery. If you connect two 1.5V AA batteries with a capacity of 2000mAh each in parallel, the voltage remains 1.5V, but the total capacity becomes 4000mAh. This means the batteries will last longer but will not provide any additional voltage.

Parallel connections are often used in systems that require higher capacity or longevity. Such as in certain types of UPS systems or power banks.

Series-Parallel Stacking

Sometimes, for applications that require both higher voltage and higher capacity, batteries are stacked in a series-parallel configuration. In such a setup, groups of batteries connected in series are then connected in parallel.

For instance, if you connect two sets of two 1.5V AA batteries connected in series (giving 3V per set), and then connect these sets in parallel, you would end up with a total voltage of 3V (like series connection) and a doubled capacity (like parallel connection).

Safety Considerations

While stacking batteries can be an efficient way to increase voltage or capacity, it’s important to do it safely.

Always ensure that the batteries you’re connecting together are of the same type and have similar charge levels. Connecting batteries of different types or charge levels can lead to rapid discharge, overheating, or even explosions.

Never attempt to connect the positive terminal of a battery directly to its own negative terminal, as this can create a short circuit, leading to overheating and potential harm.

Finally, when setting up a series or parallel connection, make sure your connections are secure to prevent any accidental disconnections or short circuits.


Understanding how to stack batteries in series or parallel configurations is a powerful tool in your toolkit as an electrician. It allows you to customize power solutions to meet the unique needs of various devices and systems. Remember to keep safety as your priority when experimenting with these configurations.

Stick around for the next article in our series about batteries “Power to Choose: Chargeable vs Disposable Batteries” to get more information on all things battery related.

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