Can anyone recommend a good 24 volt battery maintainer?
 

I see tons of 12 volt battery maintainers out there, but not many 24 volt.

A maintainer stays connected to your battery 24/7/365 when the aircraft is not being used. They will extend the life of your battery, and help ensure your battery is ready to go when you pull your plane out for a flight.

Anybody using one they like?

“Battery Minder” 24 volt. Love it!

This one? https://www.amazon.com/dp/B01ERZ0CC4...language=en_US

Funny it says "aviation calibrated" right on the unit, but in the description it says "Not for aviation use" - WTF????

Attachment 2912

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I’ve been using mine for 9 years now. I’m almost certain mine was for “aviation use” and specifically the Gill brand battery that I’ve been using forever. I’ve had good service with them so never felt the need to change…😊

We used the battery minder for concord batteries

I use a simple and inexpensive 24v power supply.

https://www.amazon.com/Vlifree-Adjus...27170239&psc=1

I like it! What settings do you use for maintenance mode?

Been using this.

https://www.batterymart.com/p-jac022...CABEgKRPvD_BwE

I have a flooded cell battery.

However on my 182 have AGM battery and the $9 harbor freight job has maintained it for years without problem. To say, I have my doubts about these “aviation specific “ maintainers.

It's a liability thing .Scared of being sued . I went to buy seal . As soon as I said it was for an airplane they told me company policy was not to sell it due to Liability If it failed and caused an accident they could be sued

Drilling down
 

Being a nerd I drilled down on this a bit.

Basically, different battery chemistries have slightly different ideal float charges.
But not so you would really notice.

In theory,
if your float voltage is too high it could boil off electrolyte.
Similarly, if you were charging with so much current as to overheat the battery.

But in reality, once you are at trickle charging level of a few milliamps,
losses would be somewhere between imperceptible to negligible.

Chargers are just current sources with an intrinsic upper voltage limit.
Once the voltage of the charger and the battery get close, the current becomes negligible.
aka 'float'

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I go with concord sealed batteries.
Concorde's have 14 AH (when new) vs Gill at around 10AH.
And no screwing with juice.

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BTW, a cheap car battery is 50AH.
A strong marine battery is 100AH.

Aircraft batteries are intended to be 'just enough' to start the engines.
Any more capacity would be more weight, loss of payload without benefit.

--
I spoke w Concord. Their batteries can handle "lots of peak current."

All that said, I bought the specific 24 volt, desulphating one for Concorde anyways.
Intrigued by, but not convinced, of the 'de-sulphation' feature.

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For convenience,
I have the passenger side socket wired direct to battery / clock circuit w 7A fuse.
So I can charge through the socket.

I've made up a tie down thing that gives me recharging / AC power on tie down.

When I ran battery too low updating avionics the other day,
I simply recharged the battery through its lighter socket.

Same arrangement on my boat.

Necessity may be the mother of invention...
But laziness is the grand-mother!

Presto!

Love ya Dave.

We've been using the Schauer JAC2024H for 8+ years. It's available from Aircraft Spruce.
We've have no problems with it. It has a switch to select for charging for GEL or FLOODED batteries. You may need to buy an adapter or modify the connectors to suit your specific airplane.

Schauer 24V Battery Charger Brochuref