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Re: [EVDL] Press release on Firefly "Oasis" battery

Jeff Shanab wrote:

>>Then lets throw in the cycle life difference and I think it becomes

Hello Jeff,

From an article written by Noel Adams in Electrifying Times =

(, where Noel is =

interviewing Mil Ovan, Senior VP Firefly Energy, Noel writes:

"The people at Firefly Battery think that they can change this. They =

have developed a battery using lead acid chemistry that significantly =

increases the power density while improving cycle life. Lead acid =

battery chemistry is theoretically capable of delivering 216.8 Whr/Kg =

while current technology averages 30 Whr/Kg.... I haven=92t been able to =

tie Mil down to a figure on energy density but he expects it to be two =

to three times the current energy density of current lead acid =

batteries. This would put them close to NiMH at 70 whr/kg but lower than =

Lithium at 120 whr/kg." Two to three times is great. That will allow me =

to use my EV as a long range commuter.

He goes on further to write: " I asked Mil about the cycle life of these =

batteries. He told me =93cycle testing is still in progress so we don=92t =

have a definitive answer right now. It takes a long time since there are =

only so many charge discharge cycles you can do in a day. We were =

expecting these batteries to perform slightly short of NiMH and Lithium =

batteries but so far we are doing better than expected, tracking very =

closely to the cycle life of NiMH=94."

While no interview date was published on the Electrifying Times page, he =

is talking about the FY2006 Defense Bill. This means an interview in the =

2005-2006 time frame. I was wondering where you were getting your cycle =

life numbers for the Firefly's? I could not find anything so far using =

Google and there is very sparse technical data on the Firefly site; just =

enough to whet the battery appetite.

The Oasis battery advertisement page from Firefly says 2x greater cycle =

life and references 200 cycles as the start of a drop off point for the =

Fireflys. But does that mean that if I can get 1,000 cycles out of my =

Optimas, does that mean I will be able to get 2,000 cycles out of a set =

of Fireflys'?


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