lithium demand growing , page-73

NNZ, yep exactly what i'm saying. The plug in hybrids use a battery about 4 times bigger than a normal hybrid. A normal hybrid runs an extremely low depth of discharge, where a plug in hybrid needs to have a much greater depth of discharge, about 3-3.5 times, and needs to be able to drive the vehicle at full power at freeway speeds. So the battery needs to be about 3-4 times bigger in power and 3-4 times bigger in energy not accounting for the difference in depth of discharge. This is the reason why NiMH is just not practical for plug in hybrids, and why we didn't have plug in hybrids back in 1999 when the prius first came out. But at the same time to make a lithium pack that large you run into thermal issues and lifespan issues, principally with regard to increasing internal resistance, this drops the outpu voltage, and thus the output power. Remembering that 4 charges of 25% is equivalent to 1 charge of 100%. This is why the normal prius runs such a low DoD, but this would make a plug in battery impracticably large and not get around the ageing issue, where the capacity decreases with age, no matter how it's used or treated, where the maximum lifespan is 5 years. This is what is preventing their use, note that GM are trialing the A123 battery which does not have the thermal issues due to it's electrode chemistry, but has massive amounts of power capacity, though struggles with regard to energy density, thus requiring a much larger pack. They are also testing another chemistry provided by LG Chem. Apparently the bench testing is going well for both.

So the problems holding back lithiums from plug in hybrids are:

1) cycle life.
2) Ageing.
3) Power density Vs Energy density.
4) Thermal management.
5) Thermal decay.
6) Cell Swelling.

All toyota are doing is testing the water, a couple of months ago lithium wasn't even part of their plans, but the momentum of the Chevy Volt forced their hand.

There's no denying that lithium will be replacing all hand held uses of NiMH batteries, and has finally come of age in that arena. The way that these small applications get around the problems listed above are:

1) 1000 cycles is about 3 years of daily charging, which is totally acceptable for a drill or a phone. But for a hybrid, with a charge at each end of a daily commute, it's half that.
2) 5 years, is a pretty good outcome for a replacement cost of only $100
3) this is just about the number of cells and their shape with regard to the overall voltage.
4) Smaller packs need very little management due to their ability to offload heat. Though a few Sony batteries exploded.
5) User manuals.
6) Room is provided for swelling, which is not as easy to do in larger packs.

I've got about 30% of what you hold in ADY. As for Sally, i've got no idea who she's referring to.