In reply to Jones Beene's message of Tue, 6 Jan 2009 09:07:13 -0800 (PST): Hi, [snip] >First published specs for the new EEStor battery >(not the 'array' but the individual batcap component) > >http://www.gm-volt.com/h/eesu_specs.jpg > >Expected 'official' release of prototypes - end of Jan first of Fed
If I'm not mistaken, that works out to 0.291 kWh/kg which is about 7 times better than Lead-acid, but still only about 2% of the energy density of gasoline. This improves to about 8% if you take into account that an electric motor can be nearly 100% efficient, whereas a gas engine struggles to achieve 25%. At 8%, you would need to have about 12.5 times the weight of batteries as you have of gas, to get the same performance and range. My 4L car has a gas tank of 68L which at a density of around 0.75 kg/L that works out to 51 kg, so 12.5 times that would be 637 kg or 0.7 ton. That's a very significant weight increase. Of course, the quick recharge is also a very important factor, because it means you can stop for "gas" just as you now would (except perhaps more often). Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/Project.html
