Well I thought I had my battery problem solved with the pending purchase of AGM batteries. Then I woke up at 5:00am with this question in mind; do I have to have a different battery charger? The charger that will be hooked up to these batteries is a 2 bank Guest 10 amp charger, 5 amps going to each bank. I know the output is low but my question is will this charger work on AGM batteries?
marshall
I know my battery chargers at home have a setting for Standard, AGM, or Gel cell batteries. I’ll look at the Guest website and see what it says…
I’ve spent about 85% of my life’s wages on fishing, the rest I just wasted…
The Guest 2611A will charge AGM batteries but the 2610A will not. Hope this helps…
I’ve spent about 85% of my life’s wages on fishing, the rest I just wasted…
There are a lot of different opinions about battery charging. AGM batteries are still technically a lead acid battery and they charge very similar to a wet cell. Regardless of what some rumors portray, AGM batteries are not as sensitive as once believed. They often get confused with Gel Cell batteries, which are more sensitive to voltage (never use more than 14.4 volts to charge a gel cell. The newer Optima batteries are not as sensitive as earlier models.
The biggest risk with AGMs and Gels is overcharging…and an automatic maintenance charger that turns off when full charge is reached and back on if the battery voltage drops is best. Do not use the small 2 amp trickle chargers and be wary of solar chargers…as they never turn off unless equipped with an auto feature. I would never use a standard car charger without current limiting built-in.
I like to keep charging amperage at 10 amps or less per bank. 12 to 20 amps is ok in a pinch, but be very wary not to overcharge, thus shortening battery life by half or more. However, 5 amps is fine per bank…just takes a little longer.
Many of todays modern chargers automatically detect the type battery or have settings for different types. However, I’ve found the Sportsman line of Dual Pro chargers to be the simplest, best bang for the buck by far and give the least problems…plus they can be repaired. Promariners have failed repeatedly for me and cannot be repaired. The smart leads on the expensive Minn Kota smart chargers go bad regularly under the heat shrink…and the only way to repair the lead is to call the factory for more with the proprietary capacitive ■■■■■■■■ circuit built into the lead. This charger also cannot be repaired…no sealed charger can.
(From Optima) Battery Charger for Optima Batteries: 13.8 to 15.0 volts, 10-amps maximum, approximately for 6-12 hours.
(Woody…I think the Guest 2610a charger works with AGMs just as well…according to specs. If you have evidence from Guest otherwise, let me know so I can update my fil
I got in touch with the companies that make both the Dual Pro and Guest chargers which are the on board chargers that I have and heard back from the makers of Dual Pro and this charger is compatible to charging AGM batteries. I have not heard back from Guest but I am thinking from what I have read and heard it will be OK to charge these batteries. I still would like a firm confirmation from these people or a confirmation from someone out there who uses this configuration.
Thanks for the help
marshall
Forgot to mention my Guest charger is model # 2611. I did not see an A attached to the model #.
marshall
That charger is fine for AGM, Marshall. No worries…hakunamatata. 
All is well now. Thanks for all the info and help.
marshall
I just heard back from the company that makes the Guest battery chargers and Guest battery model 2611 is not compatible to charge AGM batteries. Hope this help others.
marshall
That absolutely blows me away! Thanks, Marshall.
What’s amazing is the Guest (Marinco) web site states the 2611a is:
For Flooded, Gel and AGM Batteries http://www.marinco.com/product/10-amp-dual-battery-chargepro-charger-0
Wonder what gives??? Even more reason for me to stick with Dual Pro chargers.
Jim
Trying to figure this out like you the web site for Guest states the charger 2611A is compatible but my unit does not have the “A” on the end of 2611. The “A” must be a newer version.
Maybe the “A” is for AGM.
Thats the website that I looked at as well Jim. I think you’re right, the “A” is for AGM because the 2610A lists supporting documents for both the 2610 and the 2610A and only the 2610A indicates use with AGM batteries. They need to update the supporting documents with the same info for the 2611A. I personally don’t use onboard chargers because I like to see the digital display of volts and charging % on my Schumachers even though its more of a hassle getting them on and off the boat after each use. (And I can buy them dirt cheap on Ebay…lol)
I’ve spent about 85% of my life’s wages on fishing, the rest I just wasted…
Marshall,
I think it would be easier if you’d just use Joby’s boat.
LOL…good one Jon Boy!
Well it is a known fact that my boat, at least at Clark Hill tournament, cannot catch a fish much less a bite. During the tournament that morning I was telling someone about our luck and he asked who was on the boat and I told him and he said “enough said”!!!
Since I’m an expert on these kind of things I’ll tell ya…Remove any tiger paws or funny shades of urange that infest your boat and your luck will improve…lol It’s worse than having a bannana on board… Though I will safely predict the Tigers will win this weekend…
I’ve spent about 85% of my life’s wages on fishing, the rest I just wasted…