The 12V equipment in a campervan, caravan or motorhome relies on a what is known as a leisure battery. This important item is not normally supplied with a new campervan or caravan whereas most new motorhomes have one as standard.
Batteries that are designed to start a vehicle are made differently from batteries specifically intended to run most appliances. This is because their operating requirements are different.
For instance a vehicle battery has to provide a high current surge to start an engine, but once that has been achieved, a vehicle’s alternator immediately replenishes the power it provided.
In contrast, a leisure battery has to provide a steady flow of current over a prolonged period and seldom gets replenished until the user recognises that its voltage level has substantially fallen.
That’s when a re-charge is duly provided. If left long in a discharged state, a battery will generally not regain its former condition. Furthermore, manufacturers often recommend that re-charging is commenced when a battery drops to 50 per cent of its full condition.
To achieve the required performance, a leisure battery should be constructed in a way that copes better with a life of repeated significant discharging followed by re-charging.
This is referred to as ‘deep cycling’ and other products that perform in this manner include ‘semi-traction’ and ‘traction batteries’, these are used on golf buggies, disability wheelchairs, and several types of warehouse vehicles.
There’s also ‘uninteruptable power supplies’ (UPS) batteries, capable of very deep cycling and withstanding a continuous charge too, these are found supporting servers, security systems and emergency medical facilities.