No harm but as said above will not last so long as a deep cycle leisure battery. I used a car battery in the 80s with no bother and it was up to the job for around 7 years! You may have problems if you have a mover though.
Perhaps the question should not be "will it do any harm?" The question should be "what is the right kind of battery for a caravan?". Shame to have such a spare battery and no immediate use but for a caravan use a lesiure battery. Car batteries are not designed for caravan use. They are designed to create a surge of power sufficient enough to start the engine. The internal working of your engine then ensure that the loss of energy in the battery is restored whilst the engine is running. The charging of a car battery is a different regime to that of a leisure battery so if your van has a built in charger it will not be right for a car battery.
Using the vans charger to charge up your car battery could possibly cause damage to the car battery.
Phil
------------- If you're not on a fell your wasting your feet and for 2014 it's.......Feb Castleton Mar North Yors Moors; Apr Sutton on Sea; May Thirsk; Jun Clapham/Riverside (Lakes); July Wharfedale; August Crakehall; Sept Knaresborough; Oct Wirral Park/Clitheroe
It depends how you use the van, if you are always on EHU it will be ok, but if you do use it on 12v only it will not do the battery any good, the plates inside can warp with the extra loads and eventually touch each other, this shorts out a cell which makes you battery one cell short of a powerpack!! leisure batteries have thicker plates etc.
Repeated deep discharges will result in capacity loss and ultimately in premature failure.
Starting batteries kept on continuous float charge(as would be the case on permanent EHU) will have corrosion in the electrodes and result in premature failure. Starting batteries should be kept open circuit but charged regularly (at least once every two weeks) to prevent sulfation.
A starter battery will work OK but it's life will be shortened.If you have no other use for it and you are prepared to accept that it will have a shortened life it wont do any harm.
Saxo1
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.
Topic: Batterys ?
