Thanks for the reply it's for my spare battery i have one already on the van all we do is off grid as we do a lot of rallying in fields bit of a sado really lol ?? The spare i have in the shed is a banner 110ap so was going to give it a full charge and put it on the van and have two batterys in line to give me longer use in the winter months because the solar panel hardly puts anything back into the battery so looks like i'll have to get a smart chargerNo, a leisure battery is essentially the same as a car battery except it has a slightly different internal construction and is 20hr rated against 10hr rated for a car battery. That means that a 100Ah leisure battery can - in theory at least - supply five amps for 20 hours: the same battery rating for car use would (again in theory) provide 10A for 10 hours. The car battery can also usually provide a higher starting current.
A normal car battery charger will do the job but do consider getting a so-called smart charger which will handle the charging sequence better. Lidl or Aldi have them on sale a couple of times a year for less than about £15.
If you can get mains to your caravan you can of course just leave the battery in situ with the caravan charger active - such action will do it no harm and keep it at at least 90% charge but will not usually achieve 100% as the smart charger will. If you are not going off grid (i.e. away with no mains) the slightly low charge will be of no consequence.
but will not usually achieve 100% as the smart charger will.