8

I am just going into my final year of mechatronics engineering, and as a project for my spare time I am looking to convert a car to fully electric drive.

At the moment I am also toying with the idea of scratch building a small go-cart like vehicle, but this would require a whole lot more mechanical engineering, which I am not as well versed in as the electrical side of things.

If I were to convert a car instead of scratch building, there are obviously things in the car to choose for:

  • Ideally low mass
  • Road legal chassis and interior
  • Good space for batteries
  • General roadworthy-ness
  • Cheap

However I don't really know what type of car, or even how to look for a car which fits these criteria. Is anyone able to suggest what may be a good vehicle?

I do potentially have access to a 1992 Corolla H/B manual for reasonably cheap, just a little bit of panel beating required. Would this make an adequate choice, or is there something about it (and other similar vehicles) which make it a bad choice?

Thanks in advance.

EDIT: Just for slightly more context, I live in New Zealand, so by legal I obviously am referring to local laws.

6

I cannot speak to local New Zealand laws, but here in the USA a common vehicle for EV conversion is the Chevrolet S10/Colorado and other small pickups.

The combination of light weight, plenty of space for batteries, and a relatively simple design make these cars ideal. Moreover, since they have been around forever they are easy to find and cheap.

Plus there are all sorts of resources from people who have already made the mistakes, so you don't have to!

  • That makes sense. For some reason I hadn't thought about ute/pickup type vehicles, but I suppose they have a reasonably low mass, and a lot of room for batteries. – Lui Jan 12 '16 at 0:18
2

You could consider a rear engined vehicle such as the MR2 or MG TF. You then wouldn't have to worry about steering or the wasted space of the drive shafts. You could even have direct drive which would be nice as you wouldn't need any shafts or cv joints etc. You could also do some pretty neat things such as brake steer. Having two separate direct drive motors would negate the need for a gearbox or differential.

Although you might get more space for batteries and better weight distribution if you use a FWD car and direct drive. This means probably using driveshafts or heavily modifying the suspension/chassis legs to accommodate motors directly on the hubs. You could use the exhaust tunnel and the fuel tank location to store the batteries. You'd get better weight distribution this way but more work trying to fit everything in the engine bay.

Good candidates would be something Japanese because if I'm correct they're cheap and readily available in NZ but also because their electrical and CAN bus systems are very nice to work with. You could reverse engineer the CAN bus data and get everything working such as the instrument cluster, ABS etc. You could obviously do this with any vehicle with enough time and money but from my experience Japanese vehicles are much easier to 'hack' than say German vehicles with multiple CAN buses and such.

1

You did not specify the era of the car you wanted to convert, but newer models are more complicated, so the simplest conversion may be something classic. One very common platform for conversion is a VW Type I, the Bug/Beetle/Karmann Ghia cars. They're light and there's room to work. However, you'd have to want to have an old car, as well as an electric conversion.

  • "you'd have to want to have an old car, as well as an electric conversion" Why is that? Do you mean for extra parts? I was considering classic cars because I did imagine them to be considerably more simple, and slightly lighter. Do you know how much lighter they are? – Lui Jan 12 '16 at 1:57
  • i meant that this is only a good way to go if you are willing to drive an old car. for whatever reason, many people are not. look up individual model weights in wikipedia articles. – Aaron Brick Jan 12 '16 at 4:36
  • Ah, okay, I see what you mean. I'd love to have an old car! Imagine putting some wicked tires on it and then abusing your from-start acceleration in some old dinger! :) And yeah I'm finding that there are a reasonable number of models missing information on wikipedia unfortunately. – Lui Jan 12 '16 at 20:01
  • sometimes looking for the article covering the chassis or platform designation gets more information than one on the exact model. you are looking for cars that are available, so they aren't the rare ones in any case. – Aaron Brick Jan 13 '16 at 1:52
1

There are many different enthusiast groups that have done this stuff. Here are a couple that jump to the front of my mind:

Haven’t been able to find much data on the green monster, but the article does reference a company that makes conversions kits, and you may be able to get some good information there.


As other mentioned above, I can’t speak to legalities in NZ (I’m in the States), but it shouldn’t be too hard to find some good data about what’s required for roadworthiness.

0

You could start from an existing hybrid gas/electric. A vehicle like this will already have the electric motor and battery; all you have to do is remove/bypass the engine, rather than starting from scratch.

  • Valid point, but I am not really looking to modify a hybrid. For a start to buy a working hybrid is out of the range I consider to be cheap; my idea is to get only a chassis of a cat - or as close to it as possible - and do all the electrical installation and what not myself. I guess I should have said that while yes, I do want an electric car, the process of making myself one is even more appealing. – Lui Jan 12 '16 at 19:59

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.