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Old 08-08-2016, 06:02   #16
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Re: Equalizing AGM batteries

Originally Posted by sailinglegend View Post

A "Reserve Capacity" test could be a much quicker way to get a result.
As batteries age a RC test and C/20 test can vary by quite a bit, over 20% in many cases.. I am very surprised yours only varied by 5%, as that is far from the norm I see when batteries start poking below 80% of rated Ah capacity.

Originally Posted by sailinglegend View Post
By the way Lifeline recommend the batteries should be replaced when they reach 50% of their rated capacity.
The industry standard (BCI) is that below 80% is considered dead, but for light loads and coastal cruising, with quality AGM's such as Lifeline's, I will still stand behind a recommendation of 65%-70% with a strong caution. Anything below 70%, for actual off shore work, I absolutely will not recommend to my customers.

I have seen far too many banks fail catastrophically once below about 75% than I do above 75% of original Ah capacity.

Hand steering, with a two-man crew, from NY to Bermuda in a storm is no fun.... While the Lifeline Group 31 reserve battery saved the day, comms wise, it was insufficient to provide refrigeration, he lost $300.00 worth of food, & the ability to drive the AP. The real downer was that when they got to Bermuda the same batteries were 2.4X the money they were here in Maine, so his total cost was a huge punch in the wallet.. I had urged the customer not to proceed with this bank, which was testing at 70.5%....

I would only advise taking any battery, including Lifeline, to 50% of as new rating if you have a strong & healthy reserve/start battery, that can do double duty, and you're close to your battery dealer. 50% for an Rv'er is one thing, on a boat it is another story...

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Old 08-08-2016, 07:38   #17
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Re: Equalizing AGM batteries

+1 Maine Sail #16

Charlie Johnson
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Old 08-08-2016, 08:33   #18
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Re: Equalizing AGM batteries

Originally Posted by Maine Sail View Post
Odyssey & Northstar can be reconditioned/reformed but this is not an EQ charge.

Can you say a few words about how that would work?

I have Odyssey PC-2150s, oldest bank of 3x is mid-11th-season, wouldn't mind squeezing a bit more life out of it if possible...

As I understand it, they want 14.7 bulk/absorption and 13.6 float. Nearest my charger comes is 14.6/13.7 so that's the normal profile setting I'm using. Other available bulk options -- potentially usable for reconditioning? are 14.8, 15.1, or 15.5...


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