> > My hunch is that even at 80% DOD I can do 0-60 in 14 fully > > loaded. (well, it depends on how heavy the passengers are.. > > but four people my weight? Sure.) > > Nope, the numbers disagree. We've been through this before; with the > NiZn voltage sag at 3C as soon as you get more than about 5% discharged, > your available battery power is about 77hp. Assuming QM is about > 2500lbs with you (alone) onboard, Jeremy's acceleration spreadsheet > predicts about 14.8s. Now add 3 more people and try it at 80%DOD... > > You'd have to do a test to tell for sure, of course.
QM is 3100 lbs - does anyone have any suggestions for 'testing 0-60 with equipment you can find in your own home'? > My comment was worded as a question specifically because I could not > recall how close your particular conversion was to GVWR, but was > reasonably sure that with 4 people onboard it would be at or over. Ah. I misread your intentions, in that case. Well, the answer to your question is that yes, with 4 adults the car is over GVWR. Stopping distance gets a little long for my tastes (but still less than my ICE minivan) but other than that things are just fine. > The weight issue isn't going to go away anytime soon; it is a legitimate > concern. One must assume the manufacturer assigns that number to the > vehicle for good reason(s), and any conversion that ignores it and > consistently operates at or over the GVWR cannot be considered an > example of something acceptable for widespread use by the general > public. I'm glad to hear that you have planned your conversion to allow But one can safely assume that if a automaker were to mass produce a car, they would use components rated for much higher weight stress and thusly the vehicle would not be over it's GVWR. I suppose if I were selling my car [which at one point I wanted to do, before I learned about what happened to everybody else who tried ;-)] the GVWR issue would be a show-stopper, since I couldn't honestly claim it was a 4-passenger car. 'Um, it's a 3-passenger, it just looks like a 4-passenger'. However, I'm not selling my car, and I feel no pangs at ignoring GVWR. > for a driver and passenger or two or cargo without exceeding its GVWR, > however, as you note, it is all too easy to point out examples of > conversions that are at or over GVWR before the driver even gets in. > Sure, they work and don't fall apart imeediately, but I suspect part of > what lets them sneak by is that most of them are not capable of highway > speed operation for the distances QM is, so they may tend to operate > mostly at lower speeds or on surface streets, or for shorter distances, > so that the greatly reduced safety margins with respect to handling, > braking, acceleration, etc. have less opportunity to contribute to a > tragedy. That's a interesting point and one that I will definately consider. However, I have already put improvements in place to compensate for the additional weight (thicker sway bars, stiffer shocks, regen, etc) so I don't think the handling is severely compromised. > > About the only place I can think of where battery temp > > management would be essential with NiZn, from what I've seen > > of it, would be Las Vegas and places with similar weather. > > I think most of the [North] American mid-west would require thermal > management: the winter temperatures are well outside of the operating > range for NiZn, and even when they aren't the pack capacity would be The batteries are good to -15.. > reduced; summer/daytime temperatures can easily get high enough to > require cooling in order to permit charging. IMHO, it just isn't > plug-and-play unless you can plug it in anytime, anywhere and safely > charge. Once more, because I don't think people have noticed this: _the batteries do not warm up when they charge_. So, while achiving plugging in in the middle of the day would require a temp corrected charger, that's all it would require. > > I don't know about you, but I don't want to drive a car that > > does 0-60 in 24 seconds. It would probably be acceptable in > > most of europe, but in many U.S. cities you would get run > > over. ;-) Well, okay, I exadurate a little bit, but it > > certainly wouldn't be very much fun to drive. > > You've never driven a Type 2 VW have you? ;^> I replaced my '70 Type 2 > with a newer, characterless North American car a year or two ago and > miss the VW terribly, even though it probably couldn't do 0-60 in even > 24s. Can a [stock] Beetle even do 0-60 in much under 24s? Lots of > these cars (Type 1 and 2) on the road worldwide, and their owners > generally seem to find them very fun to drive... it is certainly a > different experience, but still fun ;^> > > > It would still, however, have less range than QM. > > Perhaps, but not necessarily by much. I WAGged 250Wh/mi for the NaNiCl > Sprint to get >60mi range, but I notice you report 160-200Wh/mi for QM Um, no. 200-230. I wouldn't be getting the range I am except that Evercel overspec'd their batteries. (i.e. I can get more than 84 AH out of them) I'm told that as they age, I will lose some of this 'excess' capacity, so probably by the end of it's life QM will be a 80 mile range car. I can live with that. > (with you alone onboard). The lighter Sprint with its slightly higher > pack voltage would likely get similar efficiency, and this pushes the Certainly. > range up to a similar 80-100mi usable range as you report for QM. It depends on the aerodynamics, I would guess.
