PA34 Owners Organization Forum Forums Aviation Interests Maintenance Battery Minder usage

Here we go with this debate again.

I’ve left my battery minder on 24/7 for years. And currently do, here on Cat Island, where ambient temp often is higher than 80 degs. I have not had to replace batteries prematurely. My battery is always 3-green on the battery minder ready to go.

I had my A&P install a remote connection for the Battery Minder inside the Ground Receptacle plug door. Works well.

Opinions on “constant usage” vs sporadic?

I've had that same debate. Battery minder all the time to preserve the battery, or sporadically so I can detect a failure.

My mechanic's answer? "I capacity test the battery at every annual so you won't get stuck. Leave the minder on. I'll let you know when the battery needs to be replaced."

Seems sensible to me.

I'm replying again after talking to Concorde at Oshkosh. They referenced me to a "new" technical bulletin from 2023. https://batterymanagement.concordebattery.com/BatteryDocs/TB13.pdf

I have since reprogrammed my automation so the battery-minder comes on once a week, and switches off again an hour after hitting plateau.

That's for Concorde. What about others? Still leave it plugged in?
Seems like in hot conditions...like OAT 90 degress+ ... perhaps no.

I have used a good battery minder for years. I connect it after every flight and it stays on. My last battery lasted 10 years and was still starting the plane well. But after that long, I felt I had got most of the good out of it.