Lead acid batteries were invented more than 100 years ago. The process of manufacturing them, ever since producers figured out a way to fabricate batteries that didn't need to be refilled with a hose (a few decades ago) has remained stagnant. Lead acid batteries have a lot of advantages over nickel-metal hydride batteries (which are more expensive) and lithium-ion batteries (which can blow up.) Firefly Energy has developed a method how to coat the membrane, a fan-like lead lattice that allows the battery to generate electrons, with graphite foam. This development means a more efficient battery that can extract more electricity from the electrolyte, release more electricity per charge, and endure more charging cycles. Apparently this will also make the battery last longer. The foam gives the membrane a larger surface area for reactions. Firefly's Oasis batteries are designed for long-haul trucks. Truckers usually spend their nights sleeping in the truck cabin. The air conditioning/heating runs on the diesel rigs all night. This means a lot of wastage and adding pollutants to the air. However Firefly's batteries are designed to provide enough power to run the electronics in the sleeping cabin the entire night without draining the batteries.

Firefly is planning on coming out with samples of the Group 31 batteries for long-haul trucks in the first quarter of next year and begin full production in the fourth quarter of 2008. Firefly's basic technology comes from Caterpillar. Initially, the membranes in the batteries will contain lead, but the foam will essentially cover it. Eventually Firefly will try to remove the lead.
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