[FoRK] Super batteries, Electric cars with fast-swap batteries

Stephen D. Williams sdw at lig.net
Wed Mar 18 01:14:48 PDT 2009

We'll see how long it takes to get to market.

> The results are pretty astonishing. At low discharge rates, a cell 
> prepared from this material discharges completely to its theoretical 
> limit (~166mAh/g). As the authors put it, "Capacity retention of the 
> material is superior." Running it through 50 charge/discharge cycles 
> revealed no significant change in the total capacity of the battery.
> But the truly surprising features of the cell came when the authors 
> tweaked the cathode to allow higher currents to be run into the cell. 
> Increasing the rate by a factor of 100 dropped the total capacity down 
> to about 110mAh/g, but increased the power rate by two orders of 
> magnitude (that's a hundred-fold increase) compared to traditional 
> lithium batteries. Amazingly, under these conditions, the charge 
> capacity of the battery actually increased as it underwent more 
> charge/discharge cycles. Doubling the charge transport from there cut 
> the capacity in half, but again doubled the power rate. At this top 
> rate, the entire battery would discharge in as little as nine seconds. 
> That sort of performance had previously only been achieved using 
> supercapacitors.

> The State of Hawaii and the Hawaiian Electric Company on Tuesday 
> endorsed an effort to build an alternative transportation system based 
> on electric vehicles with swappable batteries and an “intelligent” 
> battery recharging network.


More information about the FoRK mailing list