Anybody know how long a normal charging session for a Battery Tender Jr generally takes? Battery Tender instructions say a fully-discharged battery will take approximately 16 hours to recharge. For those of you who have used one, is this a normal number, or can it take longer?

I put the ring terminals on my Boxster battery yesterday. The tender has a single status light with four modes: Red flashing indicates a battery with too low a voltage, or ring terminals not properly connected. Solid red indicates normal connection, and battery is charging. Blinking green indicates more than 80% charged, and can be disconnected. Solid green is fully charged, and the tender has shifted to maintenance mode.

When I first connected the tender, the status light went to solid red. I expected that, and knew that things would be charging for awhile. But it's now been more than 16 hours, with no change. I don't know how to gauge whether my battery is just slow, or if there is a problem. Everything seems normal, but... ?

Yeah, yeah, I know: First-world problem. ;)

Dave

I would not worry unless it takes longer than a couple of days.

Update: When I went out to the garage to head for work this morning, the Battery Tender status light was solid green. So it finished charging sometime overnight. That would mean it took ~36 hours to charge. No telling how low the battery was before I plugged it in. Battery is not quite four years old, so should have a fair amount of life left in it.

Dave

Terrific! If the battery is a bit run down it does take a long time for the tender to bring it up to full charge.

Yep. Now that I have a baseline to charging it, I can keep an eye on it. My concern was that I had somehow connected it wrong, or that the ring terminals I put on the battery weren't right, or something. When the only sign something is working is the color or a light, it's a bit strange till things sort themselves out.

Dave

In Florida we start looking for replacements about then.
Any time after 4 years or so you stand a chance of finding out the hard way.
The heat just bakes the life out of batteries here.

(BTW.....I use a Tender Jr on both my Boxster and Harley and it does help prolong the battery life somewhat.
But they can also give you a false sense of security.
When the battery fails, you don't get a bunch of subtle warnings......they just go)

Good info to know. Thanks! I don't know whether we have an average lifespan of batteries here. Weather in my area is moderate at best, rarely too hot or cold. Just lots of rain, which keeps the Boxster in the garage... :)

Dave