What Are Solar Battery Banks And How do They Work?

Solar energy has revolutionized the world with free and sustainable energy. Whether it be domestic or commercial consumers, both can enjoy and utilize electricity produced by solar panels. However, there is a limitation to its utility; solar panels produce electricity only when it is a sunny day.

Even though solar panels produce sufficient energy during daylight, they do not produce electricity at night. This is not a problem for on-grid solar consumers as their homes are connected to the grid supply. But off-grid consumers need an alternative to power their homes at night.

This is where solar batteries come in; they charge and store energy during the day when solar panels generate energy. As the sun sets, the solar panels stop generating electricity, but the energy stored in batteries starts powering the home.

One solar battery might be enough for small-scale consumers, who might not need to power high-wattage appliances. But for consumers needing to power an entire house, building, or facility, several batteries are needed.

For that, a group of batteries is connected to the system, and this group of batteries is called a solar battery bank. Now that you know what is a solar battery bank, let’s move on to how it works.

How Does a Solar Battery Bank Work?

Apparently, the working mechanism of a solar battery bank is not very different from a single battery. The banks charge and discharge in the same manner and also need maintenance. In fact, it works similarly to the cells connected inside a battery. However, there are a few complications with using solar battery banks that are uncommon with solar batteries.

In solar battery banks, the batteries can be either connected in series, parallel, or a combination of series and parallel, depending on the specifications of the solar inverter.

Parallel Connection
In a parallel connection, all the positive terminals of the batteries are connected, and all the negative connections are connected. The voltages across both terminals remain the same as of one battery, but the current sums up.

Since the overall voltages remain low, parallelly connected batteries make the battery safer. Moreover, most solar inverters are designed for 12V or 24V; parallel connection enables them to match these voltages.

Series Connection
In a series connection, all the batteries are connected in a way that the positive terminal of one battery is connected with the negative terminal of the second battery.

Similarly, the positive terminal of the second battery is connected to the positive terminal of the fourth battery. The overall voltages across the battery bank sum up, but the current capacity remains the same as one battery.

How is Managing a Solar Battery Bank Different From a Single Solar Battery?

Even though there are certain similarities in managing a single solar battery and a solar battery bank, there are some complications too.

Capacity Matching
It is essential to use all batteries of the same type and specification in solar battery banks. Different specification batteries are hard to synchronize and regulate in solar battery banks. The problems can damage batteries and also cause a fire.

When solar batteries are connected in series, theoretically, all batteries should get an equal charge, but they don’t. Some batteries charge more than others, and some charge far less; this reduces overall capacity and performance and impacts battery life. This is why the batteries in solar battery banks need balancing.

Maintaining a solar battery bank involves monitoring the voltages of every battery. This helps keep track of battery health and enables the consumer to replace degraded batteries and maintain performance. Moreover, in solar battery banks connected in series, if one of the batteries weakens, it impacts the overall performance of the solar battery bank.

Final Thoughts

Solar battery banks are usually used for storing solar energy on a large scale. Even though the overall cost of a solar power system becomes high with a solar battery bank but its ability to provide power makes it very useful. Moreover, it also enables the consumer to utilize energy even if it’s a cloudy day.

However, maintaining a solar battery bank is different from maintaining a solar battery. As a solar battery’s lifespan depends on various factors, one needs to take care of each battery to ensure the solar battery banks last longer.