Battery question

[SP8]

Hi all. Hope you can help with a battery question. I have a 2008 van with a factory fitted split charge system which I converted to a camper 4 or 5 years ago. The two batteries are both standard vehicle batteries and were new at the time of conversion. It looks like the auxillary battery may be knackered, I'm waiting for my son to come and test it. Over the years it has been flattened a few times so it may well be done. I'm thinking of getting a deep cycle battery to replace it with. Firstly I need to know if this would cause problems with the vehicle battery being a standard one and secondly can anyone recommend a good battery to get which will fit in the battery compartment with the vehicle battery. Thanks

Pete

[Altransit]

Ideally, the batteries should be the same capacity and type, and age, because it's not a split charge system, they are charged in parallel, and separated when switched off.
Different batteries may have different charge rates, which will affect the charging of the other one, especially if one is charged and one isn't, often the case in a Mk7 with two batteries.

[dumper]

Personally I wouldn’t use the van batteries to power the camper I use a split change and leisure battery but as you have had no problems for 5 years maybe ok.

[Cheet22]

Dumper,

Do you mean don't touch the two van batteries at all..ie, don't even add a split charge from them to my new leisure battery i plan to locate in rear for camper lights and power (with solarv and hook up connected to it)?

I like the idea of totally ignoring the van batteries to be honest, but will i regret/miss not charging my separate battery off engine?

[dumper]

No mate use a B2B charger like a Sterling I use a 30 amp one it’s feed off the van battery as mine hasn’t got the plug on the side of the drivers seat some also use a solar set up as well.

[Cheet22]

Sorry to be dumb.. But am i right here:

New leisure battery installed and connected as:
1. Solar charging panels connected to new leisure battery via mppt
2. Electric hookup socket fitted to van to allow mains battery charger connected to leisure battery
3. Also connect new leisure battery to main starter battery terminals (rearmost one under drivers seat) via split charge relay

This means i have 3 ways of charging my new leisure battery, right?

Sound right?

[bortaf]

Sounds right to me, do you already have the solar charger ?
As for the front battery i use one of those dsah top solar pannels to keep it charged, it runs the alarm, CL and radio ect so gets drined if left unstarted for more than a few weeks, i would allways change them as a pair TBH, 1 new and 1 old abttery is still an unmatched pair and may cause issue down the line ?