Larry Dighera wrote:

On 10 Jan 2007 12:59:43 -0800, "JD" wrote:

Check out the batteries from A123 Systems:
http://www.a123systems.com/html/technology.html

Li Ion batteries made with iron at 1/5 the price, twice the power
and half the weight of conventional Li Ions. They are already on the
market and are starting to show up in DeWalt's/Bosch 36V cordless
tools. They have a weight to Watt ratio less than 1 lb / 1500W ( .9
to be exact).

http://www.a123systems.com/html/_cha.../techComp.html

Parameter A123 Ml LiIon
----------------------------------------------------------------
Power Density 3,000 W/Kg 1,350 W/Kg

Weight to discharge @ 1,500W 0.9 lbs 2.75 lbs

Life at 100% DoD 1,000 500

So what's the downside to this cell for aviation applications?

The downside is that their energy density is something like 110 W-Hr/kg,
which is lower than other types of LiIon batteries, with can be as high
as 350. That means to get the same endurance, you would need twice the
weight of A123 batteries. Weight is the major issue with aviation
applications, so these batteries are heading the wrong way.