Trickle charger. Which Battery?

I'm looking at this as in ill informed novice. I'm guessing one is for engine and the other habitation. If this is the case why not alternate it between the two every few weeks.

Colin

Why not just plug in the EHU? With luck it will keep both correctly charged.

They’re cheap enough, you could buy 2. A battery maintained on trickle charge will long outlive a battery that’s subject to regular deep discharge, so would pay for itself over time.

I think an additional trickle charger might be a good idea. The engine battery is a bugger to get to, under the passenger footwell but the leisure is just behind drivers seat. Thanks guys.

I'm lost.  If you can get power to the van why not just plug it in as you would do on site and keep both batteries charged that way?  Cheaper and more effective than buying separate chargers. 

It’s a good point. I guess it depends on the spec of the EHU charging unit, some are fairly basic and can overcharge the battery reducing its life, whereas a ‘smart’ charger will monitor the voltage typically switching to trickle charge at 80% and then maintenance mode for long term connection.

if you buy a CTek charger, they come with croc clips & eyelets to bolt directly to the battery so that all you need to do to charge the battery is connect the small plug & socket together .... it's intended for hard to access batteries just like yours. 

CTek

Thanks for all the input, guys. As the engine battery is brand new, I'll put the trickle charger on the leisure battery.