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post #22 of Old 01-25-2011
Maine Sail
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Originally Posted by sea_hunter View Post
WARNING: Do not equalize gel or AGM batteries!!!!!!!!!!!!!!!!!!
one of two things might happen; screw the batteries (burn out) or screw the boat (burn up). Read your battery manual 1st.

Again, SOME AGM batteries CAN be equalized and considering the short lives this type of battery has had in the marine market many Lifeline owners are darn happy Lifeline designed their batteries to withstand an equalizing or conditioning charge..

I will post this again:

This is a DIRECT quote from Lifeline Battery:

"Conditioning/Equalizing Charge: 15.5 volts for 8 hours. Conditioning/equalizing should only be done when the battery is showing symptoms of capacity loss. If conditioning/equalizing is necessary, first go through the normal charge cycle. Once the battery is as fully charged as possible, start the conditioning/equalizing charge.

To apply a conditioning charge, first go through the normal charge cycle to bring the battery to full charge. The conditioning charge should then be applied by charging for 8 hours. At 77F (25C), the conditioning voltage should be set at 2.58 VPC (15.5 volts for a 12 volt battery). The conditioning voltage at other temperatures is shown in Table 5-2. By using the temperature compensated conditioning voltage, batteries that are not in controlled temperature environments may be conditioned without bringing them to room temperature. If temperature compensation is not available, it is best to bring the battery as close to room temperature as possible before applying the conditioning charge.

For maximum battery life, a battery must be recharged to 100% capacity. Recharging to less than 100% may result in premature battery failure. Lifeline batteries are not covered under warranty if they are not recharged properly. For more information, please refer to our warranty policy."

A more accurate statement would have been to say that some manufacturers say it is okay to equalize AGM's and some or many others prefer that you don't. As always and as you said at the end read the manual or check with your manufacturer before equalizing AGM batteries. But some AGM's CAN be equalized!

Because each manufacturer has specific requirements for their own AGM's a blanket statement can not be made for all AGM batteries. Here is Trojan's statement on equalizing AGM's.

Direct quote from Trojan Battery:

WARNING: Do not equalize gel or AGM batteries.

If you had left your statement as; "Read your battery manual 1st" it would have been accurate information.

Clearly blanket statements do not always work as applied to all brands of AGM batteries and seeing as Lifeline is perhaps the #1 AGM maker in terms of marine market volume, here in the US, that means that a lot of boaters can equalize their AGM's to get more life from them....

-Maine Sail / CS-36T

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Last edited by Maine Sail; 01-28-2016 at 08:04 AM.
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