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What's so Special about this Battery?

firefly-oasis-g31-psoc-agm-batteryWhat's so special about this pesky Firefly Oasis battery that I'm tripping over everywhere I go?

The word seems to be out about the Firefly Oasis battery. So much so, in fact, that we seem incapable of keeping them in stock, and the manufacturer is so swamped that they can’t produce enough of them!

What is it about this battery that has stirred up so much interest? Maybe it has the same sort of allure that the Ford Model T did back in the day. With a choice of just one size, it can be ordered in any color as long as it’s a rather fetching green and blue, something that wouldn’t look out of place on the mantelpiece at Christmas.

Or maybe some folk are keeping them as pets, showing them off to fellow boaters in between feeding them freshly charged volts and cleaning up their discharge.  No, there must be more to it ….

It’s a Group 31 AGM battery - Nothing ground-breaking there. It’s a  VRLA (Valve Regulated Lead Acid), AGM (Absorbed Glass Mat), PSOC (Partial State Of Charge) battery, for all you AL’s (acronym lovers) out there. It’s a nominal 12 volt battery containing lead and acid and is no lightweight, weighing in at 75 pounds. It has comparable capacity to other Group 31 batteries and has similar charging requirements. No super-acidic acid; no extra heavy lead; no kryptonite or unobtainium. Pretty boring so far, so what’s the big deal?

Foam sweet foam
- That is the big, big deal. Such a big deal in fact that Firefly have a patent on it. Instead of traditional all-lead negative plates, the Firefly battery incorporates a foam-like structure made of carbon.

Think of it like the sponge you use in the shower (many boaters do shower, I hear), only a heck of a lot less grungy and made of carbon.

All that massive surface area in the walls of the foam sponge’s bubbles means far more contact area with the acid in the battery than can be achieved with regular all-lead plates.

Imagine how much acid you could squeeze out of a sponge compared to a lump of lead, and no, please do not try that at home! All that additional acid-to-plate contact area manifests itself in several highly beneficial and unique features that puts the Firefly battery way ahead of conventional AGM’s, and on its way to approaching lithium ion performance.

  • Firefly-Domino-2-640x428Unparalleled Resistance to Sulfation–Sulfation is what usually kills AGM’s. The Oasis carbon foam AGM can operate or be stored in a partial state of charge for long periods of time without loss of capacity. It’s a true Partial State Of Charge (PSOC) battery that got put through some pretty brutal tests by the big-wig of marine electrical testing, Nigel Calder, but came out smiling and asking for more.

  • Depths Of Discharge (DOD) to 70%-90% - Whereas you’d normally discharge your regular AGM batteries down to 50% DOD, with the Firefly you can take it down to 70% to 90% without any ill effects.  That means that either a much smaller battery bank can be utilized, or more useful capacity can be squeezed out of the Firefly than from a similarly sized standard lead-acid battery.

  • Fast Bulk Charging, and topping off is seldom required - With all the extra surface area on the carbon foam negative plate, the electrons have a bigger target to hit and soak into during charging than a standard all-lead plate, so the battery fills up very quickly.

  • Superior Life Cycle- Capable of 3X the number of deep discharge cycles than that of other lead acid batteries. Now we’re getting close to lithium ion cycle-life performance, but at a fraction of the price and complexity!

  • Strong Performance in Extreme Cold and Heat- Performance range is -20°C to 50°C (-2°F to 120°F), just in case you want to go play with the penguins or snuggle in the sun with a scorpion. After sulfation, heat is the next biggest killer of batteries, so this is a big plus.

If, after reading the above, you feel compelled to join the blue-green revolution, I’d suggest not deliberating too long. There are minimal lead times at present, but there is a price increase in the works, and that will no doubt generate advance orders that will put some pressure on the supply chain. Just sayin’ …..

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Phone: (301) 352-5738
Office | Warehouse:
4831 Tesla Dr., Suite H
Bowie, Maryland 20715
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Coastal Climate Control
Cooling, Monitoring & Solar Solutions


Office | Warehouse:
Coastal Climate Control
4831 Tesla Drive
Suite H
Bowie, Maryland 20715
Phone: (301) 352-5738

Request Information
Click here for directions.