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Old 02-11-2009, 03:31 PM   #1 (permalink)
EcoModding Lurker
Join Date: Oct 2008
Location: Wichita, KS
Posts: 23

'98 Civic - '98 Honda Civic EX
90 day: 40.84 mpg (US)

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Just received lots of free Li-ion batteries- Thinking electric car?

Hello everyone!

I have been fortunate enough to come across a bunch of used/ partially defective lithium ion batteries that a company was having to pay to recycle. Basically there are enough good cells (18650 size: about 1.5cm diameter, 6.5cm long) to make a big battery pack. like 3- 55 gallon drums of batteries (approx 30% are fine I think)

First things first:
I am an engineering student (mechanical) and I am basically at zero income with school costs. I can probably put $1000 to the entire EV project- I might get some help with that though and get up to $2K- but money is super tight!

So here are my questions:
1. how the heck do I charge the batteries in a large scale EV application? Li-on batteries from what I have read are very dangerous if charged improperly. <and have rigid discharge limits too> I have basically no specs on the batteries I have...

2. I have read up on the cheap EV conversions (like forkenswift), that is what I am looking at doing. I really need help on motors and control hardware.

---2a. forklift motors- I can't seem to find any around Wichita KS- where do you get one?

---2b. I really would like to get up- to 55mph top speed with the ev... I would probably only be doing around 40 in town driving, but I want the acceleration up to 40mph to be good.

3. The controller- I read something about Paul & Sabrina's cheap 144v motor controller-- is this close to a reality? This is my area of lack of knowledge- I do not know what it takes with motor size and voltages to get a car up that fast.

4. The donor car- I have no idea yet. maybe a metro? where do you get those? It has to be really cheap...

The first task I have before I do anything else is to make sure I can make battery packs that are useful and chargeable. I have a donated 36V golf cart with dead batteries that I figured I would use for my initial project. does anyone know about li-on batteries and using them in a big home made pack???

Thanks everyone for the help!


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