Adventure Kings 138Ah AGM Deep-Cycle Battery Review

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Jay Elliott

Chief Camping Officer

This 138Ah deep-cycle battery is the largest of the Adventure Kings battery range and fits neatly inside the Kings Maxi Battery Box.

It’s a fully sealed battery that could run your campsite for a whole weekend.

It’s made with heavy-duty in mind, so it can withstand a lot of vibrations and bumps, making it a good fit for your car, caravan, or trailer. The casing made from ABS plastic is designed for four-wheel driving.

We prefer to use ours inside the Maxi Battery Box, and place it wherever is most convenient around our campsite.

8.5
Large Storage Capacity
Adventure Kings 138Ah AGM Battery

POSITIVES
  • Massive 138Ah of Storage
  • Removable Rope Handles
  • ABS Robust Casing
NEGATIVES
  • Seriously Heavy

This thing is HEAVY and comes with two rope handles so you can lift it in and out of the desired location. The casing is made from ABS plastic for durability.

There are two M8 threaded battery posts so can attach all manner of electrical accessories. The Maxi battery box includes the required screws to install the battery with ease.

The ‘Technical’ Stuff

This unit is a 138 Ah Deep-Cycle ‘Absorbed Glass Matt (AGM) battery.

What does Ah mean?

Ah is commonly utilized terminology to describe batteries and stands for ‘ampere hour’. Basically, it’s a measure of the capacity of the battery, so the higher the Ah, the more capacity the battery has to provide more power for a longer period of time.

For each ampere-hour (Ah) that a battery contains, it should deliver a constant charge of one ampere for one hour. So, in this case, this battery should be able to provide one ampere of charge for 138 hours.

In reality, we will usually be using more than one ampere an hour, especially for a fridge or other appliance, so it is more likely that through the combination of devices and lights, a battery like this might last 12-24 hours without the need for further charging.

What is a Deep-Cycle Battery?

Whilst many batteries are designed to only use a small fraction of their charge, and deliver it in a short high-current burst (e.g., car battery), deep-cycle batteries are designed to regularly discharge the majority of their capacity.

This means you get more benefit from the storage capacity of your battery. This is usually achieved with thicker active plates, higher-density active paste, and thicker separators.

More information on deep-cycle batteries can be found here.

What is an Abosorbed Glass Mat (AGM) Battery?

In AGM batteries, the sulfuric acid within the battery is absorbed by a very fine fiberglass mat, as opposed to conventional liquid acid.

Given that the acid is absorbed in this way, the usual dangers of acid spilling are eliminated, making AGM batteries a lot safer.

More information on AGM batteries can be found here.