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Thought I'd start a new thread to discuss the potential of Toshiba's new 1 minute recharge Lithium-Ion battery. Here's their press release on the matter:

http://www.toshiba.co.jp/about/press/2005_03/pr2901.htm

The major details are:
1) 80% recharge can be completed in only 1 minute, or 100% charge in ~6 minutes.
2) After 1,000 cycles there is only a 1% reduction in capacity.
3) The battery tolerates a wide range of temperatures (-40oC to +45oC).
4) The target market is hybrid batteries for use in cars and trains.
5) They aim to commercialise the battery by 2006.

So on the face of it, an EV or plug-in hybrid with these installed would be able to recharge faster than it would take to fill up with gasoline! 8)

But the big question they've not yet answered is what is the energy density of the new battery? They claim it's good (see their chart below), but no mention of figures.



Elsewhere they've mentioned a Wh/litre figure of about 200, which is about half that of the best 18650 lithium-ions on the shelf today. Assuming roughly equal mass density, then these batteries should have about 100 Wh/kg. Not earth shattering, but still more than enough to provide some decent EV range.

So, assuming a plug-in hybrid Prius (like this one) is capable of 4 miles per kWh, then for each 10 miles of EV range you'd require 25 kilos of the new Toshiba batteries. 100 kilos would get you 40 miles range and would fit nicely in the space beneath the false trunk floor in the Prius, so no space would be lost. With cycle life in the thousands, the battery would last way longer than the rest of the car. Cost of such a pack should be in the region of $4,000.

But then I got to thinking about the recharging issue - suppose you had a 200 mile range, 5 minute recharge EV fitted with these. While charging, the car would draw 600 kilowatts! At 250 volts, that's a whopping 2,400 amps!

So it looks like the limiting factor here will not be the car, but the recharging apparatus. Perhaps we'll have to fit huge capacitors underneath the filling stations to cope? :roll:
 

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clett, hi !

"les grands esprits se rencontrent" ;) : I just made my students perform the same calculation a couple of months ago as an exercise ! You're absolutely right, we're manipulating enormous amounts of chemical energy when we're filling up our tanks and we're not aware of it... so when it's about electricity, we're shocked (bad pun intended) !

We'll probably have to use much higher voltages, but that means also some safety issues. :?

Not worse however than high pressure or liquid (-253°C or -423°F) hydrogen... :shock:
 

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One characteristic not defined here is instantaneous power capability. Usually that would follow the recharge rate, but not always. If the power output does correlate with the charge rate, then this battery would be awesome!

As for current, do you realize how big the cables would have to be to deliver that kind of current? Sure, you could have caps charge slower between charge dumps, but once you connect these batteries, you'd burn up the wire, or the battery!
 

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Yeah they have to now. The current inverter on the Highlander can handle 45KW now with considerable room to handle spikes. And its at 650V. But there is room to handle more. I believe that's also what's holding back a bigger motor.
 
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