-----Original Message----- From: Jed Rothwell > The Prius battery pack lifetimes are long, not short. They last 200,000 miles, which is longer than most automobiles, and they can be recycled.
You seem to be conflating the older and safer metal hydride battery packs, which are reliable but comparatively heavy, with the newer lithium cells, which are as yet unproved over time, except that they have been used in PC's for many years. The Prius metal hydride provides only 6.5 Amp-hr capacity and weigh 53.3 kg (118 lb). One key to the long life is that they are programmed to only be recharged up to about 50% of capacity. IN effect, you seldom have over 4 Amp-hrs. The lithium cells will provide a huge improvement in terms of Amp-hrs per kg. but they operate more reliably with a full charge. And full risk. > The fact that batteries in some PCs have burned has little or nothing to do with plug-in vehicles. Other than it's the same basic technology? > In any case, batteries are ubiquitous and they are bound to fail to some extent and cause some fires. There have been over 25 million laptop battery recalls over the years, even though with every new generation of improved cell, the cause of previous failures has been said to have been "understood and fixed". The last "fix" cost Sony well over $500 million, not counting the frustration of owners and dealers. If there was a better lithium cell - it would show up first in laptops since the PC consumer will pay over ten times the price per Amp-hr than the auto companies insist on. I have high hopes for the EEStor - but as for lithium, there is no certainty that the severe past problems of lithium have been overcome. Even worse, GM vice-chairman Bob Lutz, called back from retirement, continues to exude confidence that the Chevy Volt engineering should work out as planned, with a battery supplier to be named shortly, since the original supplier A123 suffered problems with their product. Lutz said to Reuters "I would say there's almost no reasonable doubt in our minds anymore that this is going to work." Coming from him, that is almost the kiss of death for the new GM. Jones
