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Discussion Starter · #1 ·
Hi everyone here on the forums, I thought I should join as I have been getting into some serious consideration about changing over to an EV.
Can I just say that I am extremely impressed with some of the work that you all do, and I admire the determination and creativeness of people such as yourselves. You've inspired my decision to crossover to greener (and better) driving.

I'm not a technical or engineering genius (my dad is, but I dont see him until mid 2012...

I was wondering if anyone could help me out with a few questions that sprang to mind but first I feel I need to give you the details of my gas guzzler...:
Make: Hyundai
Model: Accent
Type: 5dr Hatchback
Engine: 1.3l, 82 BHP (61KW @5500 rpm)
Torque: 11.8 kgm @ 3000rpm
Weight: 1035Kg

Right here's the questions:
How much weight can I lose by removing (and of course selling) the unecessary parts?
How many batteries would be required to power an e-motor to around the same level as the petrol engine (or even half)?
What would be the theoretical max speed if it had half BHP as the pertol engine?
How cheaply can i convert it?
If I were to make switchable packs via a relay switch or something in car, would I be able to increase the range by using the wheels as generators to charge the batteries?


Thanks
Liam
 

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Hi Liam,

Have a look at this site for inspiration... http://forkenswift.com

It shows what can be done with time and ingenuity!!!

I'm a newbie but I would suggest thinking carefully abut what you want the car to achieve in terms of range and performance. Have a lok throught the garage, top right hand side on the homeboy page, noting which motors/batteries/voltages have been used.

Very broadly, the higher he voltage of the battery pack the higher top speed. The range can be altered by the capacity of the battery pack (in Ah).

I started with chosing a motor suitable and then considered batteries. Lead acid, lithium, etc.

I would say that be prepared to have to spend quite a lot of time, effort and money to get what you want.

After all my deliberations and designs I stumbled across a previously converted car which needs work but managed to save a lot of time and effort. It had a good 9'' motor which was what I really wanted.

A good source of part information can be found by following the adverts on the right hand side of the pages on this site.

I'm in the UK too and parts are not quite so available as they are in the US.

Your shopping list is motor, controller, coupling, adaptor plate, batteries, charger, DC-DC converter (to run all the existing 12V equipment like lights, etc) or just use a dedicated 12V battery, throttle potentiometer....eerrrr....heater....eerrrrr....vacuum pump to run power brakes and/or steering as applicable....that should keep you busy!!!

Not cheap but you'll save in the long run...

Good luck and I'm happy to help, as far as I can.
 

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Hi Ace,

I'm glad there are some people with EV experience here in the UK! :D

I've watched all the videos and read all the articles on the forkenswift website, the guys are brilliant for what they did.
The whole pre-converted car thing, happens all the time like...

I'm hoping to use my current car as the donor car as I know for a fact that it wont last long... (Clutch, Cat Converter and LOADS of other mechanical failures on it right now...)

Of course money is the biggest issue I have right now, and range will have to be an important factor as well, as I travel from Edinburgh to Glasgow and back everyday (Around 70-80 Miles in total).

I had worked out previously that my car could utilize two sets of 8 batteries (96V in each lead-acid battery pack to gain a moderate max speed of 50-60 MPH). However with the weight restrictions and obvious frictions involved, it may be less.

Also I would be using a separate 12V battery for the secondary parts of the vehicle.

I was looking at a 9" motor, funnily enough...

In regards to motors and such, would it be as efficient and easier on the wallet to get those particular parts second hand?

Also with the last question asked, on the understanding of perpetual motion (which I know is not possible), would "contactless" magnetic generators provide more range at all? I usually thought that with it, it would only be 60% or less efficient but still provide better range for an EV?
 

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would "contactless" magnetic generators provide more range at all?

No
Anything like that will reduce your range - There ain't no such thing as a free lunch

Hi Liam,
Have fun investigating what is available -
I am using:
Second hand forklift motor ($100)
OpenRevolt Controller ($600)
Home made charger ($100)

If you need 80 miles range lead acid is not going to hack it

so you will have to splash out on batteries ~ $12,000
(about $2(NZ) to the pound)
 

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would "contactless" magnetic generators provide more range at all?

No
Anything like that will reduce your range - There ain't no such thing as a free lunch

Hi Liam,
Have fun investigating what is available -
I am using:
Second hand forklift motor ($100)
OpenRevolt Controller ($600)
Home made charger ($100)

If you need 80 miles range lead acid is not going to hack it

so you will have to splash out on batteries ~ $12,000
(about $2(NZ) to the pound)
Duncan's right, there's no such thing as a free lunch. First law of thermodynamics: energy cannot be created or destoyed just passed from one body to another. In other words you're better off keeping the energy in the car and use the momentum rather than transfering it (with something less than 100% efficiency) back into current fr charging. Also, if you're looking at doing a long commute like that I guess you'll be up at speed for long periods rather than start-stopping so I think regen would be limited anyway.

Again, Duncan's right. 80 miles is pretty high and lead won't do it. Have a look in the classifides on here as there is a guy selling Lithium cells at £0.71 per Ah which is a good deal. But, be prepared to have to spend a lot of cash on these. As an example: each lithium cell is 3.2 V so if you need 120V you'll need 38 of them. Let's say you need 200Ah to get that range then 38x200x0.71=£5,396!!!! But drop the guy a line as he'll do a more accurate calc for you based on the estimated Watt-Hours (Wh) of the car and this will give you a better idea. For reference to get my Golf doing 20 mile range lithium from him were £1600. Difficult to find that cash up front but it will be cheaper in th elong run!! :eek:

The Open Revolt controller looks good and I think I'll go that way too. If you feel up to it...it involves self assembly. Have a look here http://www.paulandsabrinasevstuff.com/

Duncan? How does your homemade charger work? Could you describe? I'll be going the lead route I think.
 

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Here's a calc done for me by Skool, adapted with your figures...

I would guess that your car would use 350WH/Mile at the very most.

So for 80 miles and only using 80% of your capacity you would need a 26KWH pack

26000WH / 120volts = 217AH cell size

I think the cells only go up to 200Ah...have a look you might be able to find larger ones than I have.

If you find ones large enough ones then you'll be looking at 217x0.71x38=£5,854...

You're at the very top end of EV range performance here. Forkenswift managed to do it all for under $2000 as they had a very modest specification.

Food for thought...
 
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