Market for used batteries

[FecklessDolphin]

I have two group 31 Firefly batteries which I purchased in 2016. I want to Expand the house bank to hold three batteries. Is there a market for selling the two that I have and buying three new ones so that I age my batteries evenly? Boat is in New England

[Cheechako]

Well, just try to sell them with a note on the reader board of a local marina or craig's list. Someone hard up may want them. Another option might be to get the place that sold them to replace them. They might do that on a warranty adjustment basis. So at 3 years into a 5 year battery you might get 40% off a new battery.

[Montanan]

Originally Posted by Cheechako

Well, just try to sell them with a note on the reader board of a local marina or craig's list. Someone hard up may want them. Another option might be to get the place that sold them to replace them. They might do that on a warranty adjustment basis. So at 3 years into a 5 year battery you might get 40% off a new battery.

Three year old shelf inventory stock batteries have limited value and used three year old batteries have much less value. Craigslisting is a possibility as you never know there might just be someone in temporary need of batteries, or more realistically just turn them in to the dealer that sells you the new batteries or the local scrap metal merchants and they will provide you near the recycling value which varies based on metal exchange pricing and distance from battery manufacturers. Value ranges roughly between $0.25 and 0.50. Almost all lead acid batteries are recycled.

Warranty adjustments only apply to defective batteries that do not hold a charge before the expiration date. Sounds like yours are still functional so no valid warranty claim should be available. My company designs and sells electric powered outdoor power tools powered by substantial lithium batteries. We don't utilize a proration method with our warranties instead we keep it simple with a focus on customer satisfaction, if the tool, the battery or the battery charger fail for any reason the failed item is replaced free of charge to the owner with a new replacement so long as the failure occurred during the warranty period, which is within 5 years for non-professional / residential user and 2 years for professional users [e.g. landscape maintenance, arborists, foresters. The replacement is then warranted for the same remaining period as determined from the original purchase date. The customer does need to return the defective item to the dealer for exchange with for a new replacement, which may involve shipping or driving to drop off at their expense, meaning we don't travel to retrieve the defective component.

[john61ct]

CL and eBay local-pickup, don't expect more than $100 each.

Where exactly?

[Cheechako]

Group 31 new are what.. $107 each...?

[FecklessDolphin]

Boat is in SW Harbor, Maine. Firefly Batts cost $512 new

[SoonerSailor]

Unless you have had a problem with your Fireflys, I’m going to guess that they are still almost as good as new, and simply adding the third new one will work out well. I know that isn’t conventional wisdom. You might just give Bruce Schwab a call at Ocean Planet and get his off the record opinion.

[chowdan]

I will say that FLA batteries are a pain in the rear to get rid of - atleast the 8D kind is. I had one for my starter that was less than a year old. No hits on craigslist even for $30. I ended up recycling it as I switched over to a AGM.

[FecklessDolphin]

Bruce wants me to just add a third. I am inclined to be cautious. He says a charge/discharge capacity test could reassure me by demonstrating what’s left in the existing

[john61ct]

Listen to Bruce then, especially if you've been coddling them well.

If not, bet you can flog them here once you've got results of a proper 20-hr load test.

[Emouchet]

I agree with Bruce: the FireFly batteries should not be considered as regular FLA.
Because of the carbon foam, their capacity of handling PSOC properly make them to stay at the almost new state much longer than you think.

If I was in the need of new G31 batteries, I would be a potential interested bayer. But, those Firefly are unknown for the average battery seeker.

[john61ct]

FLA means flooded, as in caps, electrolyte accessible for refilling and using a hydrometer.

Firefly are technically a type of AGM but unique in their resistance to low-DoD and PSOC abuse.

After three years though, depending on usage / care patterns they could easily be pretty worn.

Only a standardized / 20-hour load test ideally compared to one performed a few months after commissioning, would give a definitive measure of SoH.

[Shrew]

Originally Posted by FecklessDolphin

Boat is in SW Harbor, Maine.

Wow! You are just east of nowhere. I'll spend the savings in fuel just picking them up.

[Chuck Hawley]

Originally Posted by SoonerSailor

Unless you have had a problem with your Fireflys, I’m going to guess that they are still almost as good as new, and simply adding the third new one will work out well. I know that isn’t conventional wisdom. You might just give Bruce Schwab a call at Ocean Planet and get his off the record opinion.

I think this is really good, practical advice. Ideally, all batteries in parallel would be identical, purchased at the same time, etc. However, I think we sometimes seek perfection without seeing if almost perfect works well enough.

I had two Lifeline batteries that were paralleled to make my house bank (Gr 31) and one that was used as my starting battery (also Gr 31). Without going into detail, I added my starting battery to the house bank and increased my house capacity by 50%, which has all sorts of advantages (less voltage drop when operating loads, lower voltage when accepting current, etc.) I realized that the starting battery was probably "different" in some respects, as it had been cycled very little during its life compared to the house batteries. Ya know what? It seemed not to matter one whit. The newly enlarged bank worked like a charm, and the engine started perfectly with the little Gr 24 AGM that I bought from West Marine.

I had a conversation with Bill Montgomery (Balmar) about 20 years ago, and we were talking about optimizing a battery system on a boat. Precise regulation, accurate Ah measuring, temperature sensing, and so forth. He said something that I have always thought was prophetic: most boaters would be well served by simply buying a new pair of high quality batteries and upgrading their OEM alternator...

Cheers,

Chuck Hawley
Former owner of Surprise, AE 38 Yawl #6

[AndyEss]

“I had a conversation with Bill Montgomery (Balmar) about 20 years ago, and we were talking about optimizing a battery system on a boat. Precise regulation, accurate Ah measuring, temperature sensing, and so forth. He said something that I have always thought was prophetic: most boaters would be well served by simply buying a new pair of high quality batteries and upgrading their OEM slternator”

Common Chuck, get real.

What bragging rights would any self righteous dude have if all he did was replace an alternator?

He’d soon feel (depending on his self-confidence) that all the guys he’s drinking beers with at sundown had bigger ones than he did.

Personally, I mostly get bored to death when people start whipping out their latest widget to see who has the biggest/best - I like hearing stories about a good day’s sailing or exotic places sailed to.