A123 nanotech batteries hit the hobbyist market.

[skids]

Having successfully brought their new battery technology to market through a collaboration with DeWalt power tools (they are what is inside the new 36V line) A123 systems apparently now has product to sell, and they are doing so in the best possible way: directly.

They've opened http://www.a123racing.com/ selling their cells direct to RC hobbyists. Now another place for RC geeks to buy batteries may not sound like a groundshaking event, but for the first time we now have solid numbers on the A123 M1 battery cell, the first product in a family which could be the next big step forward for Plug-in Hybrid vehicles.

It looks like a single M1 cell is 2300mAh @ 3.3V -- the smallest pack sold is a 2300mAh, 6.6V 2-pack. So that's 7.59 Watt hours per cell. They can be run at 30C (226W) continuously (which of course would run the cell out of power in 2 minutes) and can charge in 15 minutes. Yes that's 226W -- enough power to run your average refrigerator -- from one cell you can hold in the palm of your hand. Unlike Li-poly and other current high-power Li-ion batteries, these won't go into thermal runaway and explode if maltreated.

Let's stack these up against typical modern NiMH batteries like those used in current model hybrids (though other Li-ion tech has been gaining ground and may even be shipping at this point for all I know.)

A123 Power density @30C (by mass): 2.9KW/Kg
NiMH Power density @30C (by mass): 1.3KW/Kg
A123 Power density @30C (by volume): 5.4KW/liter
A123 Energy density (by mass): 100Wh/Kg
NiMH Energy density (by mass): 46Wh/Kg
A123 Energy density (by volume): 182Wh/liter
NiMH Energy density (by volume): 150Wh/liter to 240Wh/liter


(This image is from a Li-poly manufacturer: http://exa.com.tw/exa/advantage.htm)

...so we can see that energy-density-wise these are not a huge step up. However these are power-optimized cells -- A123 has stated they are working on a formulation that concentrates on achieving energy density instead of focusing on power, and I think they demonstrate here that they are within striking range.

Power-density-wise, and in the area of stability, abuse tolerance, recharge time, and lifetime, the new Li-ion batteries coming onto the market now pretty much blow everything but ultracaps away. Which means these would be a great fit for current non-plugin hybrids which keep a shallow energy store, but PHEVs will probably want to wait for energy-optimised reformulation.

As for dollars and cents there are a few confounding factors: trying to determine the price of a large battery pack from small hobbyist units is folly. These are priced at $25/cell. If we assume the Dewalt 36V pack is a 10 cell single string, the price there is $15/cell. In addition, one must consider that the round-trip efficiency of an NiMH cell is somewhere in the mid-eighty-percent range while these should be in the mid-to-high-ninety-percent range, so the cost of the power waste over the lifetime of the cell has to be factored into NiMH.

Are there other companies claiming high numbers like these? Yes, but those that have products are Li-poly vendors, and Li-poly has the unfortunate tendency to explode. Those that aren't li-poly -- well in my book it doesn't really count if they aren't being made/sold in quantity yet. The only serious competitor I've seen for A123 at the moment is Valance's Sapphion which while neck and neck, is a bit harder to acquire as it seems to be only sold to manufacturers of other products. So get a move on all you other guys.

[eppur_se_muova]

1. Thanks! K&R&bookmarked. nt