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Comment by chrsstrm | Hacker News Reader

What's the weight of the 104 batteries and the gain/loss after removing the gas engine and replacing with electric?

A123 cells are about 180wh per kg, hes using 20ah 4 at 104 cells in series. so thats about 104 3.7 = 396 volts at 120ah. multiply that together you get 47kwh of energy. These batteries would be around 500lb.

These battery pricing must've came down a lot over the past couple years because this would've cost something like $40k couple years ago, but a quick google for pricing looks like the battery pack he is using can be bought for around $13k pricing source: http://www.a123rc.com/goods-468-Excitingly+Powerful+A+123+20...

500lbs in batteries and a quick search shows each of his motors is 156lbs. Since the gas motor he took out weighed 326lbs, he's got a net gain of ≈ 480lbs. That's a lot to overcome.

That's a 16% increase in weight and a 312% increase in power. I used to be a frequent poster on s2ki (autocross an AP1), the weight isn't that much of a hinderance when you increase power that much. Braking and turning will suffer.

These cars offer excellent balance, handling and braking from the factory. I'm guessing all of those may suffer after gaining that much weight.

I had an '05 S2000. I wish I still had it, wonderful car.

Agreed. Best car I ever had (and totalled).

Add on (or take off I guess) the exhaust system, gearbox and fuel tank and he's probably shaved a bit more off as well.

s2000 is a rwd car and likes to spin. this is not a trivial question.

"The battery pack will consist of 416 cells with 4 cells in parallel and 104 in series...The batteries will be A123 20Ah prismatic cells. " Approx 460 pounds just for the cells.[1]

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Notes: http://www.a123systems.com/prismatic-cell-amp20.htm

~500g each (1.1 lb) based on a quick google [tbc]

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