What Is A Caravan Leisure Battery?

Well, in a lot of ways it’s exactly what it says on the tin. A caravan leisure battery is a battery within your caravan which is designed to provide power to any and all 12V appliances in your caravan or motorhome. They will easily provide power to your kettle, television, radio, and any other appliances that you might have in your caravan.

They’re designed to work consistently over a lengthy period of time, making your caravan into a mobile home rather than a box full of furniture.

At first thought, leisure batteries might sound like the same thing as car batteries, but that isn’t the case – they’re two very different power sources!

The main thing which separators car batteries and leisure batteries is the way in which they produce power. A car battery is designed to produce a brief burst of power to boost the engine of a car into life. On the other hand, a leisure battery is designed to supply a smaller amount of power for a prolonged period of time.

Because they’re designed to work in different ways, they’re constructed very differently too. A car battery has thinner plates and different separators, which means that it would not be well equipped to deal with a prolonged period of lower energy.

On the same level, a leisure battery would not be well equipped to work as a makeshift car battery.

Can You Charge A Caravan Leisure Battery While Driving?

You certainly cannot change a caravan leisure battery while driving. The process of changing the battery in a caravan is very involved, meaning that you certainly couldn’t do it while the caravan was in motion.

To change the battery in a caravan, you need to first make sure that everything is as safe as it can be – ensure that no one is smoking nearby, and turn off all power within the caravan.

Then, open the caravan compartment, and remove the battery. It helps to place the battery onto a surface that’s near the same height as the battery compartment – just because you won’t have to lift it up when you’re done: caravan batteries are exceptionally heavy.

When you’ve moved the battery onto your work surface, unplug the cables from the top. Modern caravans will likely pop off like a lego brick, while older caravans may require a small spanner to loosen them.

Once it’s completely unplugged, move the old battery away from your caravan. Then, move the new one into the position that you just moved the old one away from. Plug the cables from your caravan into the matching terminals on your new battery. Then, replace the battery in the battery compartment, and close the panel.

Because of all the steps involved in this process, not to mention the inherent danger of large, heavy batteries, we would certainly not recommend changing the battery on your caravan while the caravan is in motion. In fact, we wouldn’t recommend being in the caravan at all while the caravan is in motion – it’s a particularly unsafe thing to do as caravans are not safety tested for collisions.

What Do You Need To Do To Charge a Caravan Leisure Battery When Driving?

This is actually a fairly common way of charging the leisure battery in a caravan – there’s every chance that you might not be doing anything else for the time as you’ll be driving or a passenger. Therefore, making use of that time to charge your caravan is wise indeed.

Every car’s engine has an alternator. It is, essentially, an electrical generator that converts power from your engine to power suitable for powering in-car appliances, such as the radio.

The car will use the electricity generated by the alternator, but we can also use this electricity to charge the battery for our caravan. There are two methods: traditional split charging, and battery-to-battery charger.

Split charging is the classic way to do this, and it’s the method that you might already be using. Simply, the voltage generated by the alternator is directed to the leisure batteries. To make this happen, you could use an isolator switch, a split charge relay, or a voltage-sensitive relay.

A battery to battery charger is a more expensive way to charge the leisure battery, but it’s also much more intelligent. The voltage sent to the leisure batteries changes based upon their optimum charging profile.

Both methods are fairly straightforward, and you can easily find assorted different tutorials and products online which will help you to properly charge your battery.

Is It Safe?

Yes, it certainly is safe to charge your caravan’s leisure battery while driving! It’s the method that people have been using for quite some time now, so it’s got a long track record of being safe.

However, there are a couple of things to bear in mind when charging your leisure battery.

For example, a split charge relay will never fully recharge a leisure battery. This is because of the physics of charging a battery. Without getting to deep into it, there are three main stages of charging a battery: primary, bulk, and final. A great way to imagine it is in terms of a sponge.

A sponge which is completely dry and has been drying in the sun for days will take a few moments before it starts to effectively soak up water. When the sponge is slightly wet, it will soak up water much more rapidly. When the sponge is quite wet, it will struggle to absorb the final few drops of water.

Similar principles apply when charging batteries – the primary charge can be difficult to initiate, the bulk charge is very easy to facilitate, and the final charge can be tricky too. The way that power sockets deal with this is by alternating the voltage in the circuit slightly to achieve a full battery.

Split charge relays will only recharge the bulk stage of a battery – this is because their voltage is constant, and therefore will not change to allow you to charge different phases of the battery. If you rely heavily on charging while driving, we’d recommend spending the extra money on a battery-to-battery system, as the voltage will automatically adjust to fill your battery completely.

One final thing to bear in mind is whether or not you’re using lithium-ion batteries. These batteries are very expensive, so you really need to make sure that you’re using them properly in order to prolong their life.

A good thing to bear in mind is to avoid overcharging them. They don’t take kindly to being overcharged, and their charge profile has a much smaller voltage tolerance than other alternatives.

What this means in practical terms is that you should only use the battery to battery charger recommended by the battery manufacturer – lithium batteries are too expensive to take risks with.

If you don’t want to spend the extra money on a battery-to-battery system, then your alternative is simply to hook up to battery charging when you get to the campsite. This is how the batteries in caravans are really designed to work, and it is the best way to allow you to fully charge your batteries at the right time and at a good speed.

Of course, using this method does mean that you’ll have to ensure you can stay at campsites regularly, but if you’ll be doing that anyway then it’s certainly a good system.

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