Firefly Carbon Foam Batteries

The ONLY carbon foam battery on the market

What makes Firefly "game-changing" technology?

Unparalleled Resistance to Sulfation

Sulfation is what usually kills AGM batteries.  The Oasis carbon foam AGM can operate or be stored at a partial state of charge for long periods of time without a loss in capacity.

Depths of  Discharge to 80%-100% of rated capacity

This can be done without any permanent sulfation or loss of capacity

Superior Life Cycle

Firefly batteries are capable of 2-3X the number of deep discharge cycles than that of other lead acid batteries


What is carbon foam?

Firefly’s proprietary technology comprises a carbon foam based porous foam with thousands of open cells/pores.

Carbon foam structure redistributes the small separator reservoir of a conventional battery to the pores of the active foam battery plates themselves. This increases the efficiency of the lead-acid chemistry because each microcell has its full complement of sponge lead or lead dioxide and sulfuric acid electrolyte.

In carbon foam, the discrete microcells collectively make up a new type of electrolyte structure (3-D electrode, pictured on the left). This results in higher power, energy and cycle life, as well as greater energy delivery and faster recharge capabilities relative to a conventional lead-acid battery.

When compared to lead-acid chemistry, Firefly’s advanced battery technology increases the cycle life by a factor of two to three times, but it can be built for three-fifths the cost of other advanced material batteries.

How do Firefly batteries perform in the real world?

Watch this video by a live aboard family in the Pacific Northwest who upgraded to Firefly batteries in 2015.  They reduced their generator run time from 2-3 hours/day down to running every other day.  After a year and a half they reported that the batteries were still performing flawlessly.

Firefly “Oasis” Battery


    • Available in size G31 -12V, 116Ah, 13.6″ x 6.7″ x 9.4″
    • Unparalleled resistance to sulfation
    • 2-3 X the cycle life of other deep-discharge batteries
    • please see manual for charging requirements

Firefly’s Performance in Independent Testing

Independent PSOC Testing by Compass Marine

In independent PSOC (Partial State Of Charge) testing of AGM batteries done by Rodd Collins of Compass Marine for Practical Sailor, the Firefly AGM was the only AGM to regain FULL capacity after 30 PSOC (one month) of cycle testing.  For a full description of the testing procedure, see:
Click on the graph to the right to see how Firefly performed after 30 cycles of “abuse” during the testing:

Nigel Calder's analysis after a season with Firefly batteries

While these batteries had proven their resilience since their inception in multiple land-based applications, the first well-documented field test of the battery in the marine environment was done in the summer of 2014 by Nigel Calder.  As a marine systems guru and author of the Boatowner’s Mechanical and Electrical Manual, Nigel Calder’s opinion is respected by boaters world wide. He has commented on his first season of use as well as followed up with a report on their performance after a winter of storage at 38% state of charge. 

Charge Characteristics by Coastal Climate Control

The experts at Coastal Climate Control put together this graph showing the difference in performance between Firefly and a slightly smaller sized, new, high-quality, marine AGM battery.  The graph shows that the Firefly battery can accept a higher charge for longer and the current tapers more slowly than the competition.


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