Try this Samba article.   When I redo mine I'll do this:

https://www.thesamba.com/vw/forum/viewtopic.php?p=5752347

Steven
91 Westy

On Sat, Dec 29, 2018 at 6:29 PM Dug Smith <dug@dugbert.com> wrote:

> I installed 4 UB12220 wheelchair batteries - they're rated at 22Ah each,
> so I'm guessing that's what you have.  Would another one help enough?
>
> I've seen somebody talking about a 100Ah Lithium battery, but it was a
> lot more than I have to spend right now.  An 80W panel in the luggage
> rack seems to (just about) keep up with the Truckfridge in the summer,
> but I haven't really pushed it by staying somewhere for very long.
>
> On 12/29/2018 15:20, Jeremy Stovin wrote:
> > Hey all,
> >
> > I’m sure I have thrown this out somewhere, but I cannot find it.
> >
> > I love my ‘87 Westy, except for the issues I continue to have with my
> house battery.
> >
> > I have done some upgrades that end up drawing a lot of power. I went
> through and found the draws. So, the biggest draws are the truckfridge and
> radio (got the switch so it won’t draw when not in use, but we like using
> it.)
> >
> > I have a series of 3 wheelchair batteries under the driver’s seat, 12v,
> 66ah. But after a day and a half, without plugging in, it is dead. I had
> installed a portable 100w solar panel and controller, but I do not see that
> helped (that is another question for another day).
> >
> > Bottom line: I want a battery with more Ah to last longer. Will even
> consider a lithium ion battery. The one, major constraint- I can only use a
> battery that will fit in that box under the driver’s seat. No room anywhere
> else. Seriously.
> >
> > So, I am asking for suggestions and recommendations of batteries that
> will work.
> >
> > (Seriously- do not recommend finding a different place for the battery.
> That will not help.)
> >
> > Some other side details: have a battery charger/maintainer, a Yandina
> combiner and a victron monitor.
> >
> > Thank for your feedback!
> >
> > Jeremy
> >
> > Sent from my iPad
> >
>