The standard battery charger is designed to charge a battery over night or 12 hours from empty to full. You can not leave it connected to the battery permanently or long time unless you want to cook it.
By RV charger, I suppose you mean better quality ( more expensive...) charger.
In these higher quality ones, they are designed to survey the battery the whole time it is connected.
If the battery is empty,it will boost the current to charge it during an initial periode (approx.4-6 hours depending on the model) then reduce the amperes until it is near full.
Then it will float the current to maintain the battery condition at its best.
It will chose the best mode depending on you battery charge level.
With these models when connected to the net, you can use the 12V appliances without draining the batteries.
You can check under
www.cristec.fr for some products.
I am just about buying CPS2 charger with a nice reduction as new CPS3 product will come in march.
If you want you can jump in... 1,2or more better price maybe