Leisure batteries – Jacksons Leisure Supplies

Your leisure battery is the heart of the electrical system. Get this right and everything else falls into place.

What you need it to do decides what you go for, and that's not just the size. It's the type. Not all batteries are the same, and two batteries with the same amp hour rating on the label can give you very different amounts of power.

There are three types

Wet lead-acid. The most basic option. Largely superseded by AGM for leisure use, but still found in older systems and budget setups.
AGM (Absorbent Glass Mat). Sealed, maintenance-free, and works with the vast majority of chargers. Reliable, well-proven, and still the most common battery type in caravans and motorhomes.
Lithium (LiFePO4). The modern standard for serious builds. Lighter, longer-lasting, and far more usable capacity. The one catch is that it needs lithium-compatible charging throughout, so your mains charger, DC-DC charger and solar controller all need to support lithium profiles.

What is depth of discharge?

Depth of discharge (DoD) is how much of a battery's power is actually usable.

A 100Ah wet lead-acid battery has a DoD of around 50%, so you only get 50 usable amps out of it. A 100Ah lithium battery has a DoD of 80 to 90%, so you get closer to double the usable storage from the same headline figure. Lithium is also far more forgiving if you do run it down further, where lead-acid and AGM can take lasting damage.

This is why comparing batteries on Ah alone is misleading. It's the usable capacity that counts.

How much capacity do you need?

Start with what you want to run. List everything: fridge, heater, water pump, lights, phone chargers, laptop. Then think about how each one gets used and for how long. Some things run continuously in the background, some get switched on as needed, some only come on occasionally.

That picture gives you somewhere to start. As a rough guide:

100 to 120Ah: weekend use, smaller vans, modest daily loads
200Ah lithium: a week off-grid with a fridge and general use
300Ah+ lithium: longer trips, extended off-grid stays, or regular inverter use

These figures assume you're putting power back in as you go. A battery is only a tank, and how long it lasts depends as much on how you refill.

Is lithium worth it?

Upfront, it costs more. But you get roughly double the usable capacity, half the physical space of an equivalent AGM, and a battery that lasts several times as long. Over the life of the build, the value stacks up.