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A Brief Guide to Understanding Battery Amp Hours 

A Brief Guide to Understanding Battery Amp Hours

Amp-hours? Reserve capacity? Volts?

There are many important terms to understand when it comes to batteries, and amp-hours (Ah) can be one of the most confusing. However, understanding amp hours can be a lot simpler than you might expect. 

In this brief guide, we’ll help you understand battery amp hours.

What Is Ah On A Battery?

An ampere hours (Ah) rating is a measure of the amount of electricity that can be drawn from a battery over a certain amount of time. The listed amp hour rating on a battery is simply a measurement of the energy storage capacity of the battery.

A battery that has a rating of 80 Ah @ 20hr would be able to provide four amps on a continuous basis. This battery will last for 20 hours at a sufficient voltage. Remember that the sufficient voltage will usually be 10.5 volts or more on a battery that is being used.

Calculating the length of time that the battery can be used based on the amp-hours is very easy. You can calculate the length of time that the battery will work by dividing the number of amp-hours (80) by the hours (20).

Amp Hours Vs. Reserve Capacity

It’s important to understand the difference between amp-hours (Ah) and reserve capacity (RC). Although they are similar, they aren’t quite the same thing.

Reserve capacity is a term that makes note of how many minutes a battery can hold a voltage without going below 10.5 volts. This is usually used for automotive purposes.

Keep in mind, however, that the reserve capacity is always about twice the size of the amp hour rating. If you mistake one for the other it can be dangerous. You may end up killing your battery since you’ll deplete it more than you expected. 

Deep Cycle Vs. Starter Batteries

Amp-hour ratings are typically only found on deep cycle batteries.

As a rule of thumb, you should realize that if a battery has an Ah rating then it means that it is a deep cycle battery. Starter batteries for vehicles, for example, will not carry Ah ratings.

A starter battery isn’t created to provide a continuous amount of power but is instead used for small bursts. It can be used to do things such as crank care engines.

Starting batteries are typically used to power a car but it’s usually recommended that you don’t power a car with a deep cycle battery. Deep cycle batteries are often known as marine batteries and have more specific purposes such as powering boats, golf carts, and other recreational vehicles. 

If you’re looking for great batteries, you may want to check out the XS Power collection now.

Understanding Battery Amp Hours

If you want to buy the right deep cycle battery, you need to understand amp hours. Remember that battery amp hours are simply a measurement of a battery’s storage capacity over a given period of time.

In need of more tips for buying batteries? Start reading over our blog to find more useful guides.

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