Long term battery storage.

I connected many a trio of 12-volt float chargers to golf car and marine 6-volt configurations. One maintainer for every pair of batteries is about the right capacity. Break the tripled pair with two disconnected series cables. Wrap the loose lugs with tape to keep them from flopping around and shorting. This is a simple and easy fix, and you end up with multiple 12-volt floating chargers instead of one dedicated 36 volt unit. The three maintainers will also keep the six batteries charged better. The more cells you have in the chain the more there is to go wrong with the process. I have a monster 60 lb center tap transformer that renders around 2.72 volts O/C. I use it to balance out unequal charging of my 24 battery 12 cells in series system. Splitting an 18-cell golf car system into thirds(six cells each) will render a better maintained system.

Sam Spade wrote:

westend wrote:

I maintained a fleet of over 50 carts for a couple of MN winters. The carts were charged and parked outdoors with no charger present.

A TOTALLY different situation.
The colder the batter IS, the slower the chemical reaction is that causes self discharge.
The difference between what happens at 100F and 0F is HUGE.

No doubt but what is the temp inside the fridge?

westend wrote:

I maintained a fleet of over 50 carts for a couple of MN winters. The carts were charged and parked outdoors with no charger present.

A TOTALLY different situation.
The colder the batter IS, the slower the chemical reaction is that causes self discharge.
The difference between what happens at 100F and 0F is HUGE.

westend wrote:
For the price of some of these 36 V tenders, you could buy a cheap refrigerator and park them in there.

I maintained a fleet of over 50 carts for a couple of MN winters. The carts were charged and parked outdoors with no charger present. In the Spring, nearly all came back to life. The one or two that didn't move were probably on the cart boys' abuse schedule.

There's a big, big difference between a few months of MN winter and several months in FL weather. The FL batteries will self-discharge many times more rapidly due to the substantially warmer temperatures. A rough rule of thumb for lead acid batteries is double the rate of self-discharge for every 10 degrees C warmer, or (assuming a 40 degree C temperature difference) maybe sixteen times faster in this case comparing FL to MN.

beemerphile1 wrote:
Use the charger you have but plug it into a timer.

This is your best option. Get a timer such as the following one:

Intermatic timer

It can be set to turn on for 30 minutes each day which should be sufficient to maintain full charge.

For the price of some of these 36 V tenders, you could buy a cheap refrigerator and park them in there.

I maintained a fleet of over 50 carts for a couple of MN winters. The carts were charged and parked outdoors with no charger present. In the Spring, nearly all came back to life. The one or two that didn't move were probably on the cart boys' abuse schedule.

If you have a fixed voltage charger it is junk anyway and may as well be replaced.

36v Deltran Battery Tender on Amazon

Use the charger you have but plug it into a timer.

You could always rearrange the batteries in a 3 x 12V configuration and use a (sufficiently sized) 12V maintainer.

Leaving them for several months in Florida heat without a maintainer would not be a good plan. That's equivalent (in terms of self-discharge) to a few years at freezing temperatures.

GordonThree wrote:
Isn't Florida over 80F for about 8-9 months out of the year, especially in a garage / enclosed space?

Yes. Well over 90 most of the summer in an uninsulated garage if there is no shade.

Leaving them sit with no float charge for that long in that kind of heat is a death sentence. AGMs might survive. Conventional wet cells, probably not.

You could hook up the charger and put it on a timer to run a couple of hours once a week. But that's a bit iffy too.

A reliable neighbor is the best bet.