It depends on what you want to run. If its only lights then 1 battery is enough. If you want to run a compressor fridge, satellite tv, microwave etc then a second battery might be needed. But there will be a weight penalty and you will need somewhere for it o fit etc.

As long as you have enough battery to start generater ..
A bridge to engine battery to start on emergencies is nice ..
Well in mine if controller switches off .. There's no power for generater ..
Have to switch relay to motorhome batteries..

I have a 105 a/h in the tug running a 32 lt engel. It is charged form a ctek 250s dual when driving. In hot conditions it will drop to 12.5 volts after 24 hours. I'm picking up a 100 watt portable solar panel to keep it topped up when camped.

I have a 105 a/h in the van running a 32 lt waeco, 15"tv, led lights, 300 watt inverter which charges laptop battery, camera battery, phone. It is charged from 180 watt solar panel, flat mounted on the roof, through a steca 15 amp regulator. I has never dropped below 12.5 volts.

Cheers Pete 

Whatever is right I wish I knew, have two very dead 100ah batteries in the van. well not quite dead the solar panels boost them through the day but they drop their charge to about 10 overnight.
Have to go out and replace them now. Always something to spend money on.

Neil - depending on the type of battery, you may be upv for replacing them. If you drop below a certain charge they can develop a "memory" and will not fully re-charge, not no matter what you do. Best bet is to get them tested by an auto-electrician (not Battery World or those sort of places who often will "write off" otherwise good batts and sell you new ones)

Doug. We have 2 x 110 amh batts and run 2 x 80w solar panels. I have a Honda 2 genie and it just fits inside the 'van tunnel where I keep it. When outside (and only the once) its chained up; along with my Baby Q and the 9kg gas tank I use with it. I also keep my 2 x 9kg 'van tanks chained onto the frame and fit a towball lock when stopped. Carry a ladder on the rear towbar so I can keep solar panels clean - padlocked. 2 x 25 lt diseal containers on rear - padlocked. Fishing rods in large PVC tube on rear - fitted with camlocks on end caps. Heard too many "I didn't think they'd want to pinch that" stories, so I trust no-one. Pretty much the only thing not chained down is the BOSS and no-one has pinched (yep - pun intended) her yet:(

I also have a Waeco 50 lt portable fridge (which had turned out to be not really needed). I keep it in van on 12v charge via the Anderson connection and if in a CP I padlock it outside to the 'van 240v plug and run it. We just keep our drinks cool in it. If we're free camping, it doesn't get plugged in to avoid battery drain and the drinks get warm. We've found out that we can keep enough soft drink, bottled water and soft drink in the 'van fridge not to need a portable 2nd fridge. I just keep reminding myself that I bought the bloody thing as a good package deal from Annaconda - fridge, insulation/protective cover, stand to keep it off ground, 2 x camping chairs (and the best of all - an Annaconda cap) all for $1050. Ive seen the fridge just by itself priced at $1400.

Not sure what's going on with mine at the moment. I have 280w solar panel on the roof and 2 Full River Deep Cycle AGM batteries 105 in the van.
My fridge only runs on 12 volt. The last 3 nights Ive had to turn the fridge off in the middle of the night as batteries got down to 11.9 and fridge going on, off, on, off in quick succession.
Back at my sons now over eater, have turned fridge off and emptied it.
Van was in full sun during the day and got up to high 13 every day.
Batteries just over 12 months old and 2nd solar panel installed April May of last year.

Thanks B n B will look into that

 

Thanks for that. There is a great auto Elctrician here in Hervey Bay. I used him twice last year. Will pop in and see him straight after Easter.
He's really good and not that expensive.

Note taken Doug. I Cant afford a new battery at the moment anyway so it won't be any good trying to talk me into buying one.
I was thinking I needed to see a solar expert but this gut was good last year with replacing the fuse box which was causing the fridge to play up. They also installed a couple ofextra 12 volt plugs for me at a ddifferent time.
Will go get it all checked there and see what he advises.

And what thoughts do jbrinks have on the responses, did we help or did we go off line.

Really like this forum stuff. This has been something else I have been wondering about 1 or 2. When we bought our 2nd hand Jayco Sterling it had 2 solar panels on top, 1 battery (not sure what ah thingys) but unfortunately the previous owners had installed a 24v/12v external shower. When we tried the free camp thing and used 12v it drained the battery in seconds (not using that again)and now I think it did what B&B said and has a bad memory like its owner and wont charge. It must be about 6 years old so thinking of getting new one - help what sort.

Hi jbrinks

Yes a second battery to the van will add weight, We can not afford the extra weight, my van is near it's gross weight and I don't run a TV which helps a little.

My second battery in the car is my back up, so 12 weeks, then 6 weeks follow by 4 weeks and now we are 4 weeks into another 12 week trip so far so good, I very pleased with my set up in 12 months, I mostly run out of water first.

We use free camps, show grounds with power where available and when desperate the odd C/P.

Our van is single axle without the en suite, portable tent for shower and we really enjoy ourselves. Ralph.

Actually Deep cycle AGM and Gel batteries don't suffer from memory effect like NiCd's do.
From the Ritar Battery site

6. Does the deep-cycle battery have a "memory"?
No. The performance of deep-cycle batteries will be reduced over time, but deep-cycle batteries do not suffer from "memory effect" such as NiCd batteries do.

It totally depends on what size batteries you are talking about.. the difference in weight between a 50AH and a 250AH is huge... What is relevant is what your battery consumption is going to be and fit batteries to suit. Or stay in powered sites only.

Actually I decided one battery was too much so fitted 2 batteries instead. That is, one 200AH deep cycle at 66Kg was just too big and unwieldy to fit where it needed to go, but two 100AH batteries fit in easily..