John Wayland wrote: > [...] on that > note, consider how Evercell comes up to their 600 cycle > rating. They rate them at 600 cycles, because at that point, > the batteries are only delivering 80% of their rated > capacity....this means that there are still lots of usable > cycle left, and who knows how long they will keep going at > the reduced level?
Bear in mind that this is the same rationale for the cycle life rating of PbA batteries also; end of useful life is considered to be when capacity drops to 80% of rated. Whether NiZn capacity drops more or less rapidly than PbA after this point is apparently not yet common knowledge. > At > just twice as expensive as Optimas, you get a battery that > has three times the power (per weight of packs), and that > delivers probably ten times the life! I think you mean three times the ~energy~, John. The Evercel specs show rather more voltage sag than Optimas, and a lower maximum current rating: the Blue Meanie's 156V pack will dish out basically whatever the motor and control can take, but the 192V stack of NiZn can't. Range you would gain; peak power you would lose. The cycle life is also an unknown. Consider that Al Godfrey got almost 1300 cycles on his set of YTs (and they were still going strong when he sold the 914 this summer), despite their official rating of just 200 (or so) cycles in EV use. The Evercels have a better rating, but also appear to be more sensitive to temperature, etc., so how the real world cycle life turns out is a bit iffy until, say, Sheer wears out his pack. ;^> > Hiding the electric motor is something that many backyard > EVers do without much thought, after all, it works, the motor > most probably won't need to be gotten to, and it's easier. > But there is great functionality in having it in clear view, > especially from the EVangelist point of view. Since the dawn > of time, car nut types love to open the hood and see what > she's got under there! There's nothing better to evoke oohs > and ahhs from these types, than for them to see a gorgeously > simple, cylindrical Advanced DC motor lurking in place of a > cluttered greasy gas engine with all its hoses, pumps, > filters, manifolds, etc. Very well stated, John! I couldn't agree more. The average person is a bit mystified by electrical systems to start with and when they look under the hood of an EV and see the space crammed with batteries, mysterious boxes and wires snaking everywhere it is extremely difficult to convincely make the 'EVs are simpler and more reliable' argument. (Even though, if the space were full of hoses and mechanical bits as in a 'normal' car, they might be unfazed.) I too am taking pains to ensure that the engine compartment is devoid of batteries (well, other than the house battery), and that the motor is readily visible to all looky-loos. > PS: Portland's Gary Graunke has his recently aquired Insight > already torn down to a glider as this is written Say, John, it was mentioned that 2 Portland EVers had purchased Insights for conversion; are you at liberty to reveal who the other is? (I take it you are not adding another steed to your stable at this time?) Cheers, Roger.
