Range of my Comutacar 200ah t875 trojans @ 72v versus Lithium?

Your calculations sound about right. The AH available may be slightly more than you calculate. Maybe as high as 100 ah.

Lithium and other chemistries look good when compared to the cost of sealed AGM batteries. A pack wouldn't be too expensive for 2-wheeled vehicle, but still really high for a car. Flooded lead-acid batteries still appear to be cheaper all things considered (including their cycle life).

The issue with floodeds though, is the voltage sags so much under high rates of discharge that the power out is low. So, peukert (reduced capacity), and battery DC resistance (voltage sag), both factor in to reduce the usable energy. This hits the batteries particularly hard in cold temperatures because both the capacity, and the voltage sag get worse, and the available energy drops a lot. It also means high rates of discharge really tend to drastically effect floodeds. This makes sealed AGMs which have a lower DC resistance a better choice for high-rate discharge, and they would probably give you a bit more range at high speeds. They also hold voltage better through the discharge cycle. My experience is that floodeds tend to be weak all around, and their performance starts poor and gradually gets worse with SOC during the discharge cycle. AGMs on the other hand tend perform good, and remain at a fair level of performance until the charge is low (<80% SOC).

Personally, I wouldn't want to ever use floodeds in an EV again, unless it is for a slow utility vehicle. They just have such poor performance, and are so drastically effected by temperature. Then there's the issue of acid corroding everything and getting on clothing, and having to water the batteries. I think flooded are particularly a poor choice for any high-speed road EV, though they are very practical for fork lifts, golf carts (and other slow-moving personal carriers), and airport tugs.

If you wanted a battery with a much lower DC resistance, than something like B&B AGMs, Exide Orbital 34XCDs, or Hawker Odysseys would be a good choice. These would not give much better slow-riding range over the floodeds, but the range when riding at higher speeds may improve by a lot, and the performance would also be a lot better. Unfortunately, the cycle life would not be as good as the floodeds. Some Universal, or "werker" brand may be gotten fairly cheaply. Batteries Plus carries the werker brand and they may give a good discount for a large order.

Trojan carries a VRLA Gel battery that you may check into which is designed for electric vehicles. I'm not sure of the DC resistance, which might not be much better than floodeds. These would need to be balanced somehow, and charged at a lower voltage than floodeds or AGMs. But, they wouldn't vent or leak any acid, and wouldn't need watering.

Have you seen these: Cloud EV LiFePo4 ? They wouldn't give the manufacturer away, but they did say they are not Thundersky. I suspect Cloud EV would probably not sell a product that is junk, but I have no way to be sure on this.

You asked a heap of questions.

There isn't enough info to answer most of them.

I am working on replacing my 40ah SLA pack with 40AH Thunderskys on my e-max. I am expecting a 60$ improvement. Hopefully, I will be able to report my result in a couple months. Any LiFePO4 applications need to use a battery management system if you hope to get good cycle life.

I haven't heard on any homebuilt EV getting more than 60 miles range, so maybe you should set your sights down a bit. Per this site: http://www.electricmotorsport.com/store/ems_ev_parts_batteries_thunder_sky.php

270 AH x 72 volt's worth of Thunderskys would cost 16,000!

The firefly is supposed to be a lead acid battery with very high electrode surface area to create much higher energy and power density than ordinary lead acid - in theory. Bit even if their hype is true, these new battery developers mostly looking for large manufacturers or the deep pocket "defense" industry for which they can be the exclusive supplier for the duration of their patent, in the meantime, patent licenses issued deliberately prohibit batteries large enough for EV's. This is the current case for NiMH batteries until the patent expires in 2015. That's why Toyota cannot offer a plug-in hybrid. This sort of monopolistic, anti-competition behavior that anti-trust laws wer made for, but US courts are packed with judges who rather like monopolies.

Next question, I have trouble imagining finding twenty wrecked Priii, or Insights anywhere - you'd probably have to comb the continent. There are probably specific special rules regarding wrecked Priii - they probably have to taken to a Toyota dealer first for removal of the batteries, so you wouldn't find any in there anyway. They are NiMH's, by the way - and require some fancy charging management.

The insight motor looks like it's 3 phase. Check here:
http://www.insightcentral.net/encyclopedia/enmdm.html
http://www.insightcentral.net/encyclopedia/enmotor.html

My guess is any brushless controller for 3-phase motors may be able to. I expect it may take some experimenting. And, I'm not sure on what type of position sensors the motor has.

In terms of 100 miles with lithium, it would take a lot less than 300 ah at 72v to get 100 miles at less than 25 mph. Maybe even half that or less.I would check into any group purchases of thundersky batteries. Do a net search. I think that's by far the best option for the range you want.

I don't think a generator is a great idea to use regularly because it will probably take cargo space, pollute, and be a maintenance burden. Not to mention a series hybrid is not very efficient because of the compounding losses. 40%? for ICE, 85% for generator, 85% for batteries (when they are charging and the vehicle is not being run), 95% for controller, and finally 85% for motor. Why not just drive the wheels directly with the ICE? I think taking a stock ICE car, and electrifying it for a fair electric range with light lithium batteries may be a better option, and far more versatile with unlimited range.