Leisure battery advice

Sorry that should be agm.

Having just bought a new battery for our caravan, I agree it's a minefield - a fact which the NCC acknowledges and there is some useful information on their website.

Just get the largest (physically & electrically), you can fit/afford. The charger should be able to handle anything available, it will just top out at it's current supply capacity. Personally I'd not pay the extra for gel over lead acid but that's your call.

Another idea is to fit two leisure batteries. I have an additional one in the bottom of the wardrobe, and the solar panel controller charges to two seperately.

My concern is that the 12v system nowadays powers things that are no longer additions, but essentials. The batteries are connected through high current plugs so that they can be swapped over should the main battery be discharged too far to run the motor mover when needed.

We had a similar set up to Navigateur with 2 batteries being charged by the solar panel, although we carried the second  battery in the tow vehicle whilst travelling. When we took the van into the dealers for some (unrelated) warranty work, he nearly had a dicky fit about using a second battery in anything other than the designated battery compartment.  He said it is a potential fire/health risk due to not enough ventilation in the caravan. He suggested we put the second battery in the open air outside the caravan when using both batteries

Just relating what we were advised. I’d hate for anyone to have problems. 

I'm using a sealed gel battery from medical equipment carried in its custom designed transit case, so should be safe. Not like the "battery under the seat" that seemed to be the only way in a motor caravan at one time.

Interesting to note how many holes are provided in a modern caravan to vent any gas escape, yet the battery is fitted in a sealed compartment! As Basil Brush might have said .... "

Had a similar experience having moved my battery to a cupboard in the end kitchen to get the van's nose weight to a manageable level. When I traded in, the dealer threw a wobbly.

For what it’s worth, today I ordered a new battery from these folks...

https://www.tayna.co.uk/leisure-batteries/

Prices seem good 👍

The OP has a Motorhome not caravan so keeping a spare in the tow car is not an option!

The NCC have a battery approval scheme and list the makes on their website. 

Unless you want to use the battery off EHU for significant lengths of time I would buy a sealed lead acid battery 110 Ahr or thereabouts but check the dimensions. The charger will cope with any size you choose to fit but may not be compatible with AGM.

You could fit a second battery if you have room but you may need a different charger system. A solar panel would be a better option if you are spending a lot of time off grid.