Thread: AGM Battery Charger

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Does anyone have a recommendation on a smart charger for an AGM (absorbed glass mat) battery (XS Power or Odyssey type)?

Roger, we've been using the AGM batteries in our Harleys for years (these are OEM HD batteries) along with the Battery Tender brand of chargers. I have two of the Battery Tender Plus and one of the BT Junior, I wouldn't use anything else.

Here is a link to Battery Tender, check out the FAQ.

Mike

Originally Posted by Mike52

Roger, we've been using the AGM batteries in our Harleys for years (these are OEM HD batteries) along with the Battery Tender brand of chargers. I have two of the Battery Tender Plus and one of the BT Junior, I wouldn't use anything else.

Here is a link to Battery Tender, check out the FAQ.

Mike

Mike,
The guys at XS Power say charge before use, and mentioned that a small charger will not work, but the BT FAQ seems to point to it just taking a long time. For an initial charge do you ever "restart" the charge cycle, giving it multiple "hits" at 14.4V? Or do you just put it on a BT Plus and leave it for several days?

Roger, I always fully charge a new battery before it's put into service. The BTs can take up to a couple of days to bring a battery to full charge due to their low charge rate, the BT Plus charges at 1.25A, the BT Junior at .75A. If the battery needs to be put in service sooner, I'll use a regular automotive type charger set at 2A for the initial charging, then attach the BT to maintain the battery while the vehicle is parked. I've found that using a BT on our Harleys has increased battery life from a couple of years to 4-5-6 years. Hope this helps.

Mike

Originally Posted by Mike52

Roger, I always fully charge a new battery before it's put into service. The BTs can take up to a couple of days to bring a battery to full charge due to their low charge rate, the BT Plus charges at 1.25A, the BT Junior at .75A. If the battery needs to be put in service sooner, I'll use a regular automotive type charger set at 2A for the initial charging, then attach the BT to maintain the battery while the vehicle is parked. I've found that using a BT on our Harleys has increased battery life from a couple of years to 4-5-6 years. Hope this helps.

Mike

Mike,
I talked to Nathan at XS, and he says that to get a "full" charge one needs a 15 amp multi-phase charger, but a 10 amp will do. After a bit of discussion he said that for street use (something with an alternator) the Battery Tender type chargers will work OK, and the alternator will push the battery to full charge during the first run of significant time. Their caution is for batteries used for competetion, where the guys make a run, come back into the pits and hook up the charger, and get ready for another run; or for high zoot audio applications where they have banks of batteries pushing many, many watts. In those applications the "float" charge will never get the battery to a full, 100% deep cycle charge, according to the maker. I'll look for a BTPlus at the NSRA this weekend. Another couple of days at low charge is not going to kill the battery. Thanks for the help!!

Originally Posted by Mike52

........ I have two of the Battery Tender Plus and one of the BT Junior, I wouldn't use anything else.
Mike

I'll add a vote in agreement.

Here is a link to a BT Plus for $31.50, free shipping, you won't find a better price.

Mike

Originally Posted by Mike52

Here is a link to a BT Plus for $31.50, free shipping, you won't find a better price.

Mike

Mike,
That is indeed a great price. Once again, thanks.

Great price - wish they had that when I bought my two BT Jrs. (I use one on my car's battery and leave it hooked up and the other for the two camper batteries (switch 'em back and forth every week during winter storage)