Project Description

How do you calculate amp hours on a battery bank? This is a question many consumers want to know when purchasing batteries or buying power stations that “tie” AGM or lithium batteries together for everyday use or emergency power needs. So, let’s get into the nitty-gritty about how you can calculate battery bank amp hours.

What Are Amp Hours?

First off, let’s define what an amp hour is. An amp hour, or Ah, is a measure of how much current one battery can provide over a defined period, which in this case is measured in hours. Depending on the size of the battery in question, amp hours can also be calculated in smaller units. For example, AA batteries usually gauge power in milli-amp hours or mAh.

Deep cycle batteries, which are designed with more robust battery plates and materials to handle frequent charge and discharge cycles, are measured in Ah, as well as with “C” ratings.

Simply put, a C rating is a battery’s capacity discharged over time. For example, a C8 rated battery will discharge its stored power over an eight-hour time frame, while a battery with a C20 rating will run for 20 hours before being completely discharged.

Calculating Amp Hours

How do I calculate amp hours? The equation is fairly straightforward. One amp hour (Ah) is the quantity of energy one Ah can discharge in one hour. Here’s a simple equation to calculate amp hours.

A (amps) x H (hours) = Ah (amp hours)

If a device uses 40 amps and you use it for 10 minutes, simply plug these numbers into the equation A x H = Ah, which would be:

A (40) x H (0.166, which is 10 minutes ÷ 60 minutes/one hour) = 6.64Ah

And voilà, you now have a formula for calculating amp hours.

Calculating Amp Hours of a Battery Bank

A battery bank or battery pack is a series of individual batteries connected together. They can be set in a series or parallel, and they’re often used to store energy generated by solar power systems. By linking multiple batteries together, the amps and voltage of the combined battery bank can be increased to meet your power needs. Additionally, battery banks are often more cost-effective than other power storage methods.

How do you calculate amp hours on a battery bank as opposed to a single battery? Again, the basic equation here is fairly straightforward. If hooking batteries up in parallel, simply add the Ah together. Here is an example of two 12V, 50Ah batteries:

Two 50Ah batteries: 50Ah + 50Ah = 100Ah

If wiring batteries in a series and you want to know the voltage, calculate the voltage through simple addition arithmetic: So, for two 12V, 50Ah batteries, add the combined volts of the different batteries together:

Two 12V (50Ah) batteries: 12 volts + 12 volts = 24 volts

The Inverter Store’s Battery Banks

The Inverter Store has years of experience selling and helping customers select batteries and power stations to meet their emergency and off-grid power supply needs.

Get in touch with us today for more information. We ship all over the U.S. and offer extended warranties on the majority of products we sell.