AutoblogGreen

I think there must be some confusion here. There is a difference between energy and power.

From Engadget:

"new kind of lithium ion battery that can supposedly store 20 times the power"

When talking about batteries, people don't usually say that a battery stores power, but rather that a battery stores energy.

Here @ ABG, the title of the story is a 20x power improvement, but later Jeremy says "twenty times higher energy capacity."

There is a huge difference between energy and power, which on is it?

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I'm with the first commenter-- which is it? Energy or power? And if we're talking about power, is it output or input? 20x the energy capacity would be an earth-shaking breakthrough. 20x the usable power input would be worthwhile, and would enable a much greater recapture of energy when braking and very high-speed charging. 20x the power output would be mildly interesting, but mostly useless unless you think we need twenty times the horsepower in hybrid car electric motors.

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But if they DO have 20X more energy, then the power can come from coupling them in series with ultracapacitors.

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Another article which claims 20X longer battery life:

http://www.itexaminer.com/PCs/tabid/75/articleType/ArticleView/articleId/429/Lithium-Ion-batteries-to-last-20-times-longer.aspx

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I think we're just seeing confusion over power versus energy. 20x power density versus your typical 18650 cell is basically what AltairNano's cells do. I've not seen even any theoretical tech that could come close to 20x energy density. I've seen an 8x better anode** and 2-3x better cathodes, and you could probably cut some weight in electrolyte and casing, but overall, I wouldn't expect better than, say, 6x energy density improvement.

** - No, the silicon nanowire anode isn't really 10x; it's 10x on the first charge cycle, but after a few it drops to 8x.

Power density isn't that important in all but racing EVs. It's a lot more important in power tools, RC cars, grid load balancing, and so on. Of course, having a high power density *is* beneficial to EVs indirectly, in that it tends to be associated with long cycle lifes.

By the way -- speaking of Subaru, they *do* have an energy density improvement. The G4e prototype uses LVO anodes. Their batteries reportedly get double the energy density of traditional li-ion. I'd love to put some of those in an Aptera and get the range of a Tesla ;)

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"which is it? Energy or power?"

Neither. The Nikkei article was mistranslated. It It's the number of charge cycles. 10,000 charge cycles, according to the mistranslated Nikkei article. The article linked by Wave54 got it right. 10,000 charge cycles is about 20x what standard lithium batteries last.

10,000 charge cycles will last several times longer than your car. Advances like this could lead to ways (e.g., leasing) to reduce cost to the consumer.

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Is there a reason I can't find any follow-up on this article: Nothing on Hitachi Maxell's site, nothing on Fuji Heavy Industries site, nothing on the University's or the National Institute's site? Is this article for real?

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