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Electric Car Engine Weight

  1. Jun 1, 2007 #1
    Hello everyone. Currently my brother and I are considering converting a gas engine car into an electric engine car. I'm still not exactly sure how well the vehicle we have chosen for this project will work. The main issue I'm worried about is weight. So, I was wondering if, in general, a conversation from gas to electric would increase the weight or decrease it. At first I was assuming that an electric engine would weigh less then the gas engine and all the components needed to run a gas vehicle, but then I realized the batteries will probably add a large amount of weight. So, before I go into more specific research of the measurements I would like to have a general idea of whether the weight is going to be an issue or not. Thank you for time.
  2. jcsd
  3. Jun 2, 2007 #2


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    A typical lead acid battery has a useful energy density of around 15Wh/kg. Gasoline is something like 45MJ/kg.

    That should get you started.
  4. Jun 2, 2007 #3


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    Li-Poly batteries will weigh a lot less than lead-acid batteries, but they have a nasty habit of exploding if overcharged. Because of li-poly batteries and more efficient brushless motors, radio control aircraft are making the switch to electric based power.
  5. Jun 3, 2007 #4
    Even with the Li-Poly batteries I would suggest that if you want comparable amounts of miles to your gas powered car then your car is going to weight a fair bit more than a normal gas powered car just because of the sheer number of batteries.
  6. Jun 12, 2007 #5
    a hundred or two lbs less for the motor/drive train
    and a thousand or two more for the batterys

    El-trick cars are HEAVY

    google up some projects others have done
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