Electric Car Range: How is it affected by the Electric Motor wattage?

best electric cars range image

agrafa

Imagine you have an electric car with a specific battery capacity and you want to test the effect of the electric motor to the car's range.
So, assume you have 2 motors: one with A KW and another with 5A KW.
If placed on the car and used to test the range till total battery depletion (assuming same constant velocity) which motor would lead to higher range?

Answer
If the same car is moving at the same speed, it will use the same amount of energy to move it the same distance. (Weight difference between the motors will probably be negligible). The energy different motors use to supply this will vary

Assuming that both motors are rated high enough to maintain the desired speed, the biggest factor affecting range will be motor efficiency. The power rating has little to do with efficiency. It is possible that either the larger or the smaller motor could deliver the better range.

Generally electric motors with lower electrical resistance, better insulation, lower magnetic reluctance and smaller air gaps will have higher efficiencies. Running a motor closer to its voltage limits will mean less power losses. (Power losses=ampxampx resistance)

This link has some typical examples of motor efficiency curves versus output power.(EFF v Wo)
http://www.cyclone-tw.com/dc24.htm

Work out the power range that you car will need, to maintain your desired speed. Then you can then look for the motor with the best efficiency curves to match your needs.(and gearing).

In short it is more a matter of how well the motor is made and how well it matches your needs then what it is rated at. A larger motor will usually run more efficiently at its rated load. If it is running well below that then the smaller motor may well give best results.

The trade off for longer range is usually slower acceleration.

What are the different types of batteries used in Electric Cars?

mark m

lead-acid batteries for an electric car cost about $3,000, have a range of 75 miles, and a charging life of 500 cycles.

what are some other battery types? costs? range? and cycles? that can be used for Electric Cars?

Answer
The 4 most popular are
1) Nickel family Ni-cad and NIMH
2) Lead Acid
3) Lithium Ion
4) Sodium Nickel Chloride

These are all deep cycle meaning they are designed to be discharged deeper than a normal car battery.
Lead acid are found in gulf carts for example.

Lithium Ion will probably get the most use because they hold a pretty long charge.

Powered by Yahoo! Answers

How do I convert my car to electric power?

best electric cars us image

chickenhou

I saw in a documentary that electric car enthusiasts in the US have removed a regular engine from an old car and replaced it with batteries. Apparently it can go very fast and can last up to 5 hours.

If anyone knows of a book, manual or website on how to do it I would appreciate it.

Answer
-----------------------------
If you want to do the work yourself, there's help here:
*
http://electroauto.com/index.html
and here:
http://www.austinev.org/evalbum/build
*
Here are some places to get your car converted to electric:
*
http://grassrootsev.com
http://jerryrig.com/convert/
http://www.ampmobileconversions.com/
http://labshelf.com/electric-car-conversion.html
http://www.powerhappy.com/Electricalvehicles.html
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150006318396
*
There are also ready-made electric car conversions for sale built by dedicated EV small businessmen and hobbyists - like me. Look at this page:
*
http://grassrootsev.com/convert.htm
*
The above is run by a guy who takes old, cheap cars with good bodies (mostly from the 1980s) and removes the engine. He then installs brand new electric drivetrains. All these cars do freeway speeds. The best part is the price. These cars start under $5000. You won't get state-of-the-art (ranges are more like 50 miles, not 200) but the low prices mean you'll get your investment back in fuel savings quickly.
*
Another place to find used EVs and hobbyist-built EVs is here:
*
http://www.austinev.org/evtradinpost/
*
I own an old EV, built back in 1980. EVs are extremely reliable. My 25-year-old car has all the original motor and electronic parts from 1980, which have never needed service in all those years.
-----------------------------

Electric cars how to create more energy than you consume?

jamesalbur

Listening to all the talk about electric cars and how physics doesn't allow alternators to renew their batteries leads me to ask a few BIG questions: How do we get the alternators to produce more energy than the car can consume? Also, Why can't we make the axles work for us to turn the alternators using a drive shaft? Why wouldn't stacking alternators work?

Answer
doesn't work, it would violate the laws of conservation of energy, or "you don't get something for nothing".

analogy:
Start out with a £5 note. Go to a bank and change it for five £1 coins (minus a service fee). Go to a different bank. Change your coins for a £5 note, minus another service fee. Repeat until you have several million pounds!

Powered by Yahoo! Answers