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Is there a DC battery that will fit in the recess of the passenger seat for the 2nd battery? I can't seem to find anything "small" enough to close the lid and move the seat into position. I have fitted a regular Willard for now, but need to get the correct battery for future replacement.
Should be a lower battery as the std cranking battery under driver seat.. I put my 102 Deep-cycle under the rear seat...

I just run a normal battery. Partly for this reason. There is no perfect solution anyway. Deep cycle's can handle a deeper discharge but take a very long time to recharge and that should also be done with a charger and not the alternator. For my needs, I don't normally stay in one place for a long period of time and I also need the battery to recharge quickly, the normal battery works fine. Maybe the ideal is an aux HC and DC and a DC to DC charger and a solar panel. But I'm managing fine without that fortunately!
Thanks, went with crancking battery and will install a volt meter to monitor the 2nd battery when staying over for more than a day.
A Sterling or equivalent alternator to battery charger is a very good setup. These setups come from the marine industry but have the marine price tag to match.
No thanks Russel, don't need an overlander, just a lekka 4X4 bus with added luxuries for camping etc.
Hi Benniebez -
You mentioned that you went for the normal High cycle battery in the end. How has it been coping as this was a few years back it seems?
I'm in the process of doing a lot of reading on this subject with info and views from just about everybody in the 4x4 market. Most say deep cycle with DC-DC usually C-Tek, but I'm not spending R7500 on a charger and another R2500+ on a battery! My Syncro is purely for holiday. Also it sounds that nowadays everyone insist that you can only charge a deep cycle with a DC-DC charger...although back in the 90's we all survived with 102AMP Deltec batteries and normal solenoid systems!
I'm looking at a normal HighCycle battery for my 2nd battery - same as my main battery - VARTA F17, which is a 80AMP with 740A crank capacity. Yes it is expensive @R1900, but this is the only battery that fits under the seats with 80AMP rating, 24 month warranty, and seemingly better when both batteries are the same when doing a solenoid system.
I will use a normal solenoid system from National Luna or equivalent to do the charging, used mainly for ENGEL and WEACO freezers and some lights.
When stationary and parked at home, and 220V is available I will use a 5AMP RING charger - same as C-TEK - just half the price and from the UK, to keep the batteries fully topped up.
I am still investigating the myriad of info and different devices for a solar solution, and will do that much later due to costs.
So - in short - did your normal starter high cycle battery survive serving as your secondary leisure solution?
Thank you
Hi @complete, that is my bus now. I inherited Bennie's dual system and knew nothing about it. Here is where you can read where I got educated and some googling.

Mine has a continuous current NL solenoid and does the job. 70Ah Aux. On our recent trip it did just fine.

I would like to replace the solenoid with a smart one that first allows the main to get topped up, before switching to charge the aux. They are about R700.00 from outdoor warehouse and I reckon worth the expense.
Morning Gerard,
Thank you for the reply!
I have used similar solenoid setups in the past and worked just fine, however if stationary for long and slow speed game viewing type driving it struggled to keep the 102Ah deep cycle full, hence my move towards the High cycle 2nd battery idea.
I will also will be using s smart solenoid system - LUNA with controller, but tx for the info. The guys at Mega4x4 also sell a similar system. Just bear in mind that these systems has a safety startup and only kicks in once the charge from the alternator balances out, so if you switch on your AC or anything else the countdown starts again.
I mainly wanted to know if the starter battery survived serving as the second/leisure battery as many will tell you it won't. But again some argue that a high cycle battery accepts charging easier from a solenoid system, as opposed to a deep cycle - I suppose I will have to fit and test it to be 100% sure!
I installed a dual battery system in my 2.5 5-cyl bus about 15 years ago mainly to allow me to use my old-style 220v/12v/gas fridge. Initially I just bought a second standard (High Cycle) SABAT starter battery to match what I already had but switched to larger Exides when replacement was due. I have the factory standard alternator with no relays or solenoids, just an isolator switch on the secondary battery. In theory this allows me to use one battery for the fridge and/or external camping lights and the other for starting. In practice I hardly ever separate the batteries because with the engine off even with both batteries connected the old fridge technology will flatten them in under 6 hours, but that's more than enough to keep it running for longish lunch and snooze breaks or if I forget to disconnect it when stopped. While camping I run on mains or gas. Point is, in 15 years I have never had a moment's trouble with this very simple setup so I don't see much advantage in special chargers and solenoids etc. Ideally, if I had a modern compressor fridge and @complete's 80 Ah Varta batteries I think I could probably run it all night on just one.

An extra advantage of a dual battery setup is that they last much longer - about 6-7 years- due to the shared, therefore reduced, load-cycles per battery.
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