Q for AGM battery experts

History, 83 venture. PO battery junk and replaced with AGM dec09 from batterys plus.

April 2010 battery blew up like basket ball(case swelled)-likely my fault, charged with auto battery charger at about 10A.

Battery Plus honored warrenty and replaced april 2010

Currently working on electrical mods, and about 1 month testing on bike(key on, test, key off....)battery down to 10V, never any power problems during any testing. Mods done and working great, last night decided to charge (4A) and ride in AM.

AM charger shows failure, key on and everything dead.(clock display on key off then disappears key on). V check battery=9V, amp check accross battery(20A scale)=.1A

try to recharge, and computer charger detects fault and fails to start.

Back to Batterys Plus, they test simular readings, are trying to recover battery but likely hopeless-not responding correctly to charger, warrenty expired, purchase new battery and tender(battery minder plus). If they manage to recover will be spare.

pictured 1-battery using, 2-computerized charger using, 3- new tender

Now the question, What could have caused the AGM to go completely dead overnight while on computerized charger, and it was fine power wise prior to charging?

Do I need to be leary of my computerized charger?

Fixing to go out and check key off load test, and amp test computer charger(on auto battery) to verify 2-4-6amp readings are correct. will post update.

Not having much luck with AGMs, what am I doing wrong?

update

key off=.6mA

charger at 2A=2.7A, at 4A=4.0A, at 6A=5.0A, charges for just 1 pulse then quickly detects complete charge and shuts down charge complete on all 3 cycles

While your charging issues may be to any number of things ill address the battery. The Batteries Plus batteries are just plain junk. I went through 3 of them before I switched to a Deka battery. I was sure glad they were still under warranty. The plates inside keep breaking away and shorting out. Very poor battery design in my opinion. Had the Deka now for 1 1/2 years now with absolutely no issues.

I had one of them chargers, cut the leads off and trash it..

Red light came on almost everything it touch, even the truck battery that I drive daily.

The old style charger with a needle is the best bet, but they are hard to find now...

I did go back to the computerize style and so far so good...

But that model was junk to me..

I'm afraid I have to agree with Ruffy on the quality of the Batteries Plus unit. No luck with them in the past.

The AGM's are known for having an extremely low discharge rate when not being used. I've had my DEKA now ....going into its third season. It has NEVER been on a tender and even sitting on the shelf for the winter season it does not require a charge to top it off.

Seeing 9 volts......that battery ain't coming back to full charge I'm afraid.

If there was a parasitic drain on the battery that would do it. The clock should not even affect an AGM. Being on a charger over night........I'd suspect the battery is the whole problem.

Mike

Anybody else seen the hype about the Lithium batterys from Shorai? Fist saw them on the dirt bike because they are much lighter than a traditional battery. The do have sizes to fit our bikes, but MAY be a little smaller and include some foam spacers. Reported to hold charge for a year with NO maintenance and last 2-4 time as long as lead acid. They are pricey and currently on backorder due to higher than expected demand. The jury may still be out and economist reports not back yet, but interesting non the less!

http://www.shoraipower.com/

http://www.shoraipower.com/s-57421-XVZ13-Venture-1300cc.aspx

Well,the Deka has a higher CCH than that one, and half the price. See Skydoc17 for a good deal...

Well,the Deka has a higher CCH than that one, and half the price. See Skydoc17 for a good deal...

I've got a Dekka distributor nearby and have Dekka batterys in all bikes where they are available. I'm just curious about the LI claims.

I think the LI batteries are worth watching. I'm not ready to spend that kind of money on a battery but they may well be the future. At this point though, they would have to last me about 10 years before I considered them a good value at that price. I figure they will get cheaper once there is some competition.

I am waiting on the Lithiums too. They should hold a charge a lot longer and be lighter than a conventional battery. As far as coventional batteries go I have gotten almost 5years each from Yuasa batteries.

I just posted another thread about this in the General Tech Talk area as I think there will be some good discussion on these batteries that we might want to keep around for a while.

Well, Batteries Plus just called

they were able to recover battery to 270CCA, rated 330CCA.

sounds to me like sulphided plates, although I did not think this was a problem with AGM

At least it did not drop a plate a someone above suggested. I appreciate the recommendations to use DEKA, but feel trapped into what I have-at least until it comes time to buy another battery. At that time I will get a DEKA. FYI I bought the new battery yesterday for $86, and Earl lists DEKA as $105. Not big difference, but someone stated earlier that DEKA was 1/2

Guess I will go pick the battery up and keep it as spare, better than letting them have it as a $10 core. New tender states it runs a 'anti sulphide' maintenance program (3.26Mhz pulse during float charge)(states if less than 12.2V-25%charge-start desulphate and let it run at least 1 week)

Back to my orginal question, what could have cause all this?

I am guessing in the dark here, but seems AGM is very sensitve to discharge below ~12v, and I messed up letting it get to 10V during my testing. Apperantly sulphate forms on plates during discharge, then higher then normal internal resistance during charge with my normal charger caused even more sulfide to form until cells were eventually isolated from each other. Complete removal of sulphide should get battery back to near like new condition, unsure if desulphide function of tender will do the job but will try.

What have I learned? Assuming my summation is correct, always keep AGM battery on tender, especially during testing, don't let it get run down below 12V, and if it does put on a desulfide charger ASAP! Also never charge any small equipment batteries at a charge rate higher than 2 amps!