AGMs & Maintainers

pianotuna wrote:
I would not risk a maintainer unless it were specifically for that exact battery. I.E. a charger from duracell.

Like I said.......

The vast majority of the evidence and the recommendation for MOST common AGM batteries is in direct opposition to the last two posts.

But if it makes you feel better to spend money on a fancy charger that you don't really need.....by all means go ahead.

OR take the "wrong" one you have and connect it for 24 hours once a month (assuming that there is no parasitic load during that month).

Little more info: The AGM is just over a year old. Since I haven't been using a maintainer I disconnect it for storage, as the Seadoo has parasitic draws from the electronics. With the wet cells, I'd just hook up the maintainer for storage.

I've really got no way to charge, other than the maintainer, an old (30+ years) dumb charger, or running the motor, obviously not a storage option.

As a guess, how much engine runtime does it take to bring a battery up in typical powersports usage? One hour? Two? Ten? I know, I know, hard to say for sure. And what about temp compensation? None of that on board.

People on the Seadoo website say just use the old maintainer, AGM's are pretty commonly used these days.

Mex, I am not taking your post clearly. Do you agree w/ Sam Spade or no?

And yeah, I want to get some charge on it ASAP. Looks like the maintainer is my best option.

I would just use the maintainer that you have. Do not let the battery sit one more minute at 12.3

12.3 ????? Isn't that about dead ?? If disconnected I'd say that battery is toast ?

I have 3 of those typical batteries in my electric 36v bike
And I have 2 of the AGM electric chair 35 AH in my B&D 24v lawn mower, and they are ALL charged/maintained w/ a Battery Tender JR, and have been for many years, and work great.

You do not need a temp regulated charger,....except maybe in very warm weather. But mine do just fine in 100 degrees.

WRONG! Sam Spade

You are quite correct IMHO :)

I just do not like seeing more than 13.6 volts on an AGM battery at 70F at 80F the 13.6 would be too much. The battery will not live as long. Here at 95F I have been dropping the maintain to 13.1 with a twist of my wrist. When all is said and done in Michoacan the 10-turn pot will be over my head and volt display off to the side.

I would hate to think any maimtainer can't do these numbers.

You can "roll the dice" and use the existing maintainer. You can "have a throw" at using a regular charger and manually monitor temperature. Or you buy the recommended equipment.

Personally I'd fully charge the battery and then store it. I would not risk a maintainer unless it were specifically for that exact battery. I.E. a charger from duracell.

The battery "purists" will hate this answer..........

ANY fully automatic maintainer is better than none.
And disconnecting/removing the battery probably does nothing productive.

In order to break even with buying a $100 charger over the lifetime of a 7 year battery, it would need to roughly double the lifespan......compared to the charger you already have.

Not likely that it will make anywhere near that much difference.
If it gets you an extra two years, it won't pay for itself until your 4th replacement battery......or 28 years roughly.

P.S. How many seasons has your present battery gone down to 12.3 and been left sitting that way ??