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Discussion Starter · #1 · (Edited)
Hello!

I'm looking for electric motors for my EV conversion, and I've realized that I'm horribly under-informed...

I have no idea what I should be looking for, especially in terms of voltage. I've heard that I should look for something between 100-200 lbs, and that I should be looking at forklift motors.

My ideal conversion:
-less than $3,000 to complete
-maintain 4x4 capability
-range of at least 85 miles
-able to drive at 70 mph (but usually will be driving at around 45 mph)
-charges enough to go about 20 miles within an hour and a half or less
-fully charges in 10 hours or less

My current specs:
-car weighs approx. 4,000 lbs
-automatic transmission
-4x4 capable

I know a lot of my ideal specs lean heavily on the battery specs, but I know the motor makes a difference too.

Thank you SO MUCH for ANY help!!!
 

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You're right that ability to meet the specs is largely driven by the battery choice, but that the motor and battery decisions are related.

-able to drive at 70 mph for at least 2 hours (but usually will be driving at around 45 mph)
Two hours at 75 mph would be 150 miles - far beyond your range target of 85 miles - so I assume that you means for that to be two separate items:
  • able to drive at 70 mph
  • able to drive for at least 2 hours (will usually be driving at around 45 mph)
You don't really need the endurance (driving time) specification, because the range specification will determine the amount of energy the battery needs to hold, but the information about typical driving speed is good.
 

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-charges enough to go about 20 miles within an hour and a half or less
-fully charges in 10 hours or less
Any battery capable of delivering enough power to drive the vehicle usefully will be capable of accepting charge fast enough to gain 20 miles of range in an hour and a half, and almost any battery choice that is workable for the range will be capable of accepting charge fast enough to gain 85 miles of range in 10 hours. So these are really just charger requirements, not important to the battery choice.

They're definitely not directly important to the motor choice, although the choice of voltage will determine what charger is needed. I would suggest just not worrying about these charging requirements as far as the motor and voltage choices are concerned.
 

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Discussion Starter · #4 ·
Any battery capable of delivering enough power to drive the vehicle usefully will be capable of accepting charge fast enough to gain 20 miles of range in an hour and a half, and almost any battery choice that is workable for the range will be capable of accepting charge fast enough to gain 85 miles of range in 10 hours. So these are really just charger requirements, not important to the battery choice.

They're definitely not directly important to the motor choice, although the choice of voltage will determine what charger is needed. I would suggest just not worrying about these charging requirements as far as the motor and voltage choices are concerned.
Thank you so much for your help!!
in this message and the other!!

I really need to do more research... lol

With the understanding that my battery and motor choices need to be linked, how can I determine the appropriate batteries to go with a given motor (or vise-versa)?
As in, what specifications (voltage, current, size, power, etc) should I be paying the most attention to?

Note, please, that for size, it is fair to assume that I have unlimited space (for now)
I know this is not really the case, but my car certainly has a LOT of open room, and I could take out the backseat to fit more batteries... you get the idea

Thank you again!!!!
 

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Hi Jessica11k

Don't worry about voltage (yet)
First - your location makes a big difference

Motors - your options are
Use a "power unit" out of a crashed EV - by far the best and cheapest option
BUT it does involve messing about with modern electronics

Use a forklift motor and a DC power supply
Cheap cheerful and a bit unsophisticated

Buy a "new" motor for an electric car
By far the most expensive and least powerful

The cheapest overall is to get a crashed Leaf or something and use all of the bits
 
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