Battery Storage Camper Van

Trekkie,

The best option is to leave them connected to a 3 stage battery charger which drops down to a float charge when they are full. This is NOT to be confused with a trickle charger . Trickle chargers continue to put in charge, albeit small, that will stuff your batteries in time.

You can also add a gadget from Projecta, Charge Controller BM 140 which conberts your standard charger to a two stage and floats. It has a switch for Gel of Flooded batteries.

Cheers,

Jim.

I was talking to my Auto electrician about this exact question. Ihad a battery fail and then totally stuffed it when trying to get it back.

He said that the battery needs to be constantly draining and charging to get the best out of it.

I have a small $29 from Big W solar panel that plugs into the cig socket. He suggested I get a small LED light with a light sensor switch and plug it in as well.

When the sun shines the solar panel puts a bit of charge in when it gets dark the light comes on and takes a bit out. Sort of like breathing. Now the problem is finding a light and sensor switch.

It may be cheaper to buy the 3 stage charger as Jimbo suggested.

The other alternative, but I don't think you can dco it with a gel, is to drain the battery when you store it and refill it with acid about a week before you go away.

Duncs

I too have a KK camper and was thinking about the same problem? The easiest solution for me is to just let the batt slowly discharge to about 12.3v then charge it back up using the standard batt charger that came with the camper. It won't harm the batt (although some experts might disagree) and while a float charger is good it doesn't cycle the charge in the battery. In an ideal world a good float charge that was interrupted by a deep discharge once a week would be a mickey mouse charger.

I use the Selctra charger (its fitted into the camper) and leave it hooked up all the time. Every couple of weeks turn the fridge on for a day. That way I've got a cold beer up in the shed.

That batteries need exercising is a total myth. Battery heaven is a full charge and no work. Battery makers supply graphs showing longevity/cycles of discharge - and max life always correlates with minimum use.

The reason (and only reason) for float charging is to compensate for internal leakage. This is high with starter batteries (but becoming less so with technical advances), less so with deep cycle batteries - and low/very low with gel cells and AGMs respectively.

If storing for less than (say six months) the best approach with the latter is to fully charge them and then leave them alone in a cool place. At 20 degrees C ambient or so an AGM will stay perfectly content for at least 12 months. (They were designed to do this).

If you really wish, use a permanent really top-quality genuine three-stage charger (NOT a chain store special) set up for AGM or gel cell - but anything less than that is more likely to do far more harm than good. But there's little point in doing so.

To clarify the above, AGM batteries are generally very tolerant to charging voltage and current, but because their internal leakage is so low they need a lower than usual float voltage. That voltage is temperature dependent but is typically 13.2-13.3 volts in temperate areas - and as low as 13.0 volts up here in Broome.

But most (non-adjustable conventional chargers float at 13.6-13.8 volts - far too high for AGMs - and almoit certain to cause damage.

Conventional starter and deep cycle batteries should however be kept on permanent charge (again via a really good three-stage charger) if not used regularly - or at minimum fully charged at least once a month. More often is better.
Trust this helps
Collyn Rivers

looked at buying a 3 stage battery charger and for not much more bought a 40w solar panel $300 and 3 stage solar regulator morningstar 6 $85 and use that for camping as well
put 2 bits of U aluminium channel bracket on the north garage wall that the solar panel slides and locks into at home and then unlock and take camping
have a gas fridge so the 40w powers the fluoro and radio