In between that kind of lay up you need to be charging the battery somehow if stored at home, hook it up and leave the charger running. It looks from your profile pics like home but that may be misleading?
If in storage take battery home and charge or solar panel ? (bit dear for any useful size)
Problem occurs due to the poor chargers caravans have on board not ever really gettiung the battery properly charged, which causes sulphation, which in turn makes it even harder to charge (with poor charger) which then causes more sulphation, vicious circle which leads to demise of leisure batteries.
We do store it on the drive, it is always attached to EHU so that we use it occasionly when no guest space left and i have even used it as a sewing room to replace the caravan curtains!
I don't know if George will answer this because he hasn't been around for a while but no, that is a picture of the zig unit in Susiewong's caravan.
George uses a Sterling staged charger which he says charges much better than a standard caravan unit. If you search under caravan or equipment forum on here for Sterling charger in message body you will find a lot of threads with info about them.
------------- Caz
If you can't see the light at the end of the tunnel, just keep going till you go round the bend.
> it is always attached to EHU <
Which implies that a new battery also will have a relatively short lifespan.
Batteries must be used from time to time to remain 'active'.
Take it off EHU from time to time and switch some lighting on to consume power of the battery. And only after you are certain that you used a certain amount of power, switch the EHU or charger on again to recharge the battery. This way they last much longer.