Are you confused about the differences between a leisure battery and a car battery?
Or maybe you’re just buying your first campervan, or about to start your own self-build campervan conversions and you don’t know the first thing about leisure batteries?
Whichever category you fall into, if you own or plan to do your own self-build campervan project – then eventually you will have to deal with the leisure battery.
Some of you reading this article may already know how to maintain a leisure battery. But, for the more novice reader, this article should give you a basic level of knowledge of a leisure battery.
Apart from enabling you to maintain your battery in a way that will prolong its life and keep your costs down, it’s also vital to be able to recognise signs of potential damage in a leisure battery for the safety of anyone using the campervan.
What is a leisure battery?
A leisure battery is specially designed to power all of your 12V appliances and devices. Items such as the internal lights, T.V, the kettle for the morning cuppa, the oven and so on all use leisure batteries.
As you can see, the leisure battery is an essential piece of equipment that turns your campervan into the homely domestic environment. It will make living in a campervan so much more comfortable.
What does a leisure battery do in a Campervan?
The job of the leisure battery in your campervan is to provide power to the electrical appliances when the engine is not running. This leisure battery will power most of the 12V devices and equipment in your campervan.
A vital aspect of a leisure battery is the capacity which uses the measurement of amp-hours – which is the current which you multiply by the time for which it can be supplied.
For example, a 110Ah battery can supply 1 amp for 110 hours, or 10 amps for 11 hours.
A higher Ah rating leisure battery gives a higher capacity, BUT will also take longer to charge.
The capacity is not quite as straightforward as this – we will cover those complications later.
Is a car battery and a leisure battery the same thing?
No, a leisure battery and a car battery are two very different power items. Although it is fundamentally possible to use each of the batteries in the other’s place for the short term, this is not advisable because of the different purposes of the two items.
A car battery (also called a crank or starter battery), is designed to provide a sudden burst of energy to start the vehicle engine when required.
A leisure battery, on the other hand, is designed to release a lower level of energy over a much more extended period that is used to power your 12V appliances.
Because of this, and the differences in construction, these batteries should not be regarded as interchangeable.
Are there different types of leisure batteries?
There are three main types of lead-acid batteries used in-vehicle applications. Lead-acid batteries are known as flooded batteries,
- Starter batteries – also known as cranking batteries – These are the batteries designed to provide the power to start the engine of a typical vehicle
- Leisure batteries – also known as auxiliary or deep-cycling batteries. The campervan battery discussed in this article
- Traction batteries – also known as deep-cycling batteries. Electric vehicles often use these type of batteries – for example, milk floats or lift trucks.
As well as these lead-acid leisure batteries, there are a couple of alternatives which you can use as a leisure battery.
- Gel batteries – Vehicles which have a higher than average risk of crashing tend to install gel batteries. The use of a gel inside the battery (rather than liquid) removes the risk of damage if the vehicle tips over and eliminates the risk of injury from leaking corrosive acid. In the case of campervan accident, a gel battery provides enhanced safety.
- AGM batteries – Absorbent Glass Mat batteries comprise lead plates and compressed glass fibre in a mat format in each cell. These batteries possess a much longer lifespan than a lead-acid one, but at a significantly higher price. Also, AGM batteries have a longer life, permitting more charging cycles within a lifetime of use. Finally, AGM batteries can serve as a dual-purpose starter and leisure batteries.
- Maintenance-free batteries – This is a sealed unit which does not require topping up, unlike conventional lead-acid batteries which have openable compartments to refill the liquid level.
Is a leisure battery essential? Can’t I power the devices from the mains?
Sure you can if you intend staying only on campsites for long durations of time. But, for many, having the ability to drive to new and exciting destinations whenever you please is the main attraction of campervan travel.
And if that’s the case, you will no doubt be doing wild camping at some point along your trip. If you want to power all of your devices, then you are going to need to invest in a leisure battery.
The nature of a leisure battery, aside from powering appliances, is the ability to provide a steady level of voltage over long periods.
But, a leisure battery will help keep your devices safe over their lifetime of use.
What are the safe handling procedures for lead-acid batteries?
OK, this might be a little bit of an exaggeration, but still, a lead-acid battery can be pretty dangerous if not handled correctly. Due to the flammable nature of lead-acid batteries and the corrosive properties of acid, you should always carry out the correct safety measures when you handle lead-acid batteries.
- Make sure the battery is fixed in place correctly, and that the gas escape vent is free from debris and correctly operating at all times.
- ALWAYS wear appropriate safety clothing and eye equipment when handling batteries.
- Use high-quality, fixed clamps connected to the battery to prevent any sparks and fire risk. Do not use crocodile clips for permanent connections.
Getting the most from your leisure battery
- Use a thin layer of Vaseline or petroleum jelly to the battery’s terminals to prevent oxidisation.
- Check clamps regularly for rust on the contact surfaces.
- Check that the electrolyte level covers the lead plates on the battery. If not, top up with deionised water.
- Ensure that the gas relief tube remains correctly fitted.
- Recharge the battery once it falls below 50% power and doesn’t allow a battery to run flat entirely. This will significantly reduce the battery lifespan.
- Never leave the battery uncharged. A white deposit may form on the plates, leaving the battery unusable.
- Ensure adequate ventilation to allow gases to escape while the battery is charging.
- Always use high-quality clamps.
- When you park your campervan up for a while, remember to maintain your battery. A trickle charger is a good investment for this situation.
- Buy the correctly rated charger for the battery. A battery requires a charger with an output current of at least 10% of the battery’s capacity. For example, a 110Ah battery will need at least an 11 amp charger. Any less will significantly reduce the battery capacity.
How can I check my leisure battery charge level?
Many campervans come fitted with a digital voltage meter that displays the voltage of their leisure battery. Although these are practical, often, the accuracy can be way off.
It is advisable to invest in a high-quality hand-held multimeter, also known as a VOM (volt-ohm-milliammeter).
Using one will allow you to obtain a more accurate reading about the current charge level of your leisure battery.
Always take extra care when you check the charge level of your battery. Ensure you follow all safety instructions from the manufacturer of the multimeter.
Before using the multimeter to check the battery, make sure that you:
- Switch off all electrical appliances in the campervan, including non-obvious ones like alarms, fridges and clocks that run off the battery. Failure to do so will result in an inaccurate reading as the current will continue to flow.
- Always disconnect the negative terminal first.
- Don’t smoke near a battery.
- Don’t drive the campervan or charge the battery for at least one hour. This is to allow a more accurate reading as this will let the battery to find equilibrium.
Another option is to use a continuous charging system to keep the leisure battery functioning. It is advisable to check with the battery manufacturer before considering this option to verify that the battery is suitable for this functionality.
Leisure Battery Voltage Charge Level
Below, you will find our super handy table that shows the voltage and approximate state of charge for each battery type.
|State of Charge||Sealed or Flooded |
Lead Acid battery voltage
|Gel battery voltage||AGM battery voltage|
What affects leisure battery performance?
There are several factors which may affect the performance of a leisure battery.
- Temperature – Temperature plays a significant role in battery performance. Lower temperatures diminish the capacity. The Amp-hours rating is stated based on a temperature of 25C. With each degree drop in temperature will have a 1% drop in performance.
- Age – The typical lifespan of a battery is around five years. As batteries get older, performance inevitably reduces.
- Consumption – Any leisure battery, like mobile phone batteries, are limited by the number of discharge-recharge cycles they can tolerate. Clearly, the more you use the battery, and the more power you consume, the more times the battery will be recharged.
- Rating – The more appliances you power, and the size of those appliances, the bigger your leisure battery will need to be. For example, motors or heater will require significant power and therefore, a large battery.
- Discharge Rate – The current demand for the devices in your campervan will impact the proper length of each charge cycle.
While all of these will influence the performance of the battery, it is essential to remember that there are many complex factors at play.
Why does my leisure battery sometimes smell?
This is a chemical reaction of the battery materials and is usually a sign that the battery is overcharging. Sometimes during charging, a battery can start to produce a rotten egg smell, which is unpleasant for those using the campervan.
Should you detect such a smell, carefully check if the battery feels hot. If so, the battery is overcharging, and this may cause irreparable damage.
Always disconnect the charger from the mains before disconnecting the battery. Failure to do so may cause a spark in the vicinity of the battery with disastrous consequences.
Subscribe to our Monthly Newsletter!
No SPAM, just awesome content!