Having a solar system can definitely minimize energy consumption on the grid. But when the sun goes down, using a battery bank is the solution to continue using solar after-hours.

A solar battery bank is an energy storage solution that creates a way to use solar panels when the sun is not available. The battery bank connects more than one battery to allow for more storage capacity or higher voltage depending on your needs.

A created battery banks helps with a true self-sustaining cycle of electricity use. You don't have to worry about going "back to the grid" when darkness hits just because the sun went away.

Thinking about wiring batteries can be intimidating, but it doesn't have to be! Taking the right precautions and truly understanding how batteries work for solar will help reap the benefits of your solar production.

How Does a Solar Battery Bank Work?

The idea behind a "bank" of batteries is to collectively join more batteries together in order to increase one of two things: voltage or amps.

To throw some battery terminology in the mix, let's talk about series and parallel connections.

Series Battery Wiring: Connection and Diagram

two batteries wired in series connection
12V 100Ah batteries wired in series diagram

Wiring batteries in series will increase the voltage. This obviously depends on the number of batteries used, but the principal remains.

As an example, with two 12V batteries with an amp-hour rating of 100, connecting two batteries together results in a 24V battery.

When batteries are connected, they don't really have a smart memory. In any order they are connected, the source and ground connections remain like a single battery.

Parallel Battery Wiring: Connection and Diagram

two batteries wired in parallel connection
12V 100Ah batteries wired in parallel diagram

Wiring batteries in parallel will create more capacity. No matter how many batteries are used, the capacity adds together.

For an example on a parallel battery connection, the same 12V batteries with an amp-hour rating of 100 wired in parallel will result in 200Ah  (100Ah+100Ah) capacity.

Refer to the battery bank tutorial on batterystuff.com website for more information on these types of connections.


Is it worth getting a solar battery?

The value of a solar battery depends on preference. If living with an off-grid type of setup, it will definitely be worth the cost and time to setup the battery so energy can be used without the sun.

If you are just trying to offset the cost of grid electricity with solar panels, it's possible having a solar battery will be more work than benefit.

References for more information

Understanding Battery Configurations | Battery Stuff
Find out more about battery configurations, such as series, parallel, and series/parallel. Learn how to connect two or more batteries properly.
How to Size Your Off-Grid Solar Batteries
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