Taking Apart a Flooded i-MiEV

Hi Everyone!

I bought a flood-damaged Mitsubishi i-MiEV, sight-unseen through an online auto-auction.
I've worked on a number of DIY electric vehicle projects, including building my own electric motorcycle, car, and hybrid, so I was hoping I could figure out what was wrong with the car and fix it up.

I was really hoping that the flood damage would be relatively minor, but NOPE, turns out it certainly was a Super-Storm-Sandy vehicle which got saltwater inside, including inside the battery case.

At this point, I'm pretty much just taking the entire car apart as time and space allows. It's very interesting to see how the car is assembled, what parts go where, etc. etc.

I have a number of videos on YouTube on the project already, ( http://www.youtube.com/playlist?list=PLmHss3DBZUikU6Iae3UlaNH73UojlDIkM ) and the official place for this all is at my personal transportation blog http://300mpg.org/ (Check through the dates of the last couple weeks for numerous updates.)

In a nutshell so far - the BODY looks great! (It should, it's a 2012 model year with only 10 MILES on it!), but unprotected circuit boards are most-likely not salvageable, including the BMS boards and other boards inside the battery pack. I have dropped the main pack, opened it up, and have started testing some individual cells inside. Looks like those may be usable (although at lower than stated capacity) for some other EV project.

I also talked with pretty much the only i-Miev certified repair guy in my state, and he said that besides the obvious hurdles to making the car run as stock, there are some others such as the fact the the EV-ECU and some other computers have to be "matched sets" or factory flashed to work together.

It's unlikely that this car will ever run again as a factory stock car (replacement costs on the required parts would be cost prohibitive) but it has the potential to make a pretty cool electric-to-electric conversion. Otherwise, there are plenty of brand-new parts on this car that could be used to keep others on the road and looking good! If I sell parts off this car, I will make them available through this forum first.

I'll try to answer questions as I can on this forum, but I would prefer taking comments through YouTube and 300MPG.org. If I answered questions on every forum I'm on, I'D NEVER get anything done!

For now, enjoy watching me take the car apart and see what's inside! Just think of it as CSI: i-MiEV!

-Ben
300MPG.org

I don't know what you paid for it but the cost to replace the batteries, BMS and Controller could be up to $10k dollars and more. Trying to integrate all of the cars systems (ACS, HVAC, etc.) into the new BMS and Controller would be another problem. When I saw video of the batteries, my heart sunk knowing this would be a killer to fix. Its too bad the BMS boards weren't coated to prevent the corrosion or other steps to prevent water from entering the battery compartment.

Hi Ben,

I think you might be like 7 years ahead of us in the sense that once our battery warranty runs out or if new battery/controller options exist, then we will have to go throughtt the same process as you know.

Just a thought, find yourself a US company which makes a new breed of Li xxx (sulphure...) batteries and Make a deal to give you free batteries as a means of promotion of how much more range their battery can do versus the original iMiev Battery.

That would be usefull for them to on road testing for a fraction of the cost. Plus the way you are documenting, half the planet will know about how good their batteries are and once a good upgrade solution is put together, there will be thousands of iMiev driver thought the world that will be interested.

Here are the targets, I would aim for. Range should be about three times present range. Longevity in term of cycles could be half, price should be half or less of present 10K price.

If you come up with that solution in about two years (witht the help of the sponsor) then you, we all have a winner.

Thanks

Many of us have been following you on your adventure from the very beginning, Ben - Thanks so much for the wonderful documentation! We're probably going to learn more about our cars from you than we have from all other sources combined

I'm hoping the drive train, inverter and charger can be cleaned up and used - If so, maybe you could stick a $5K set of Optimas under there and have a usable car??

Good luck with your project - I hope it turns out to be well worth your time, effort and expense

Don

Ben, having been an unsuccessful bidder for this car, I've been following your wonderful blog and videos closely. Thank you so much for posting them. My own take is that if you cannot salvage sufficient cells then you'll need to put in your own charger/BMS/battery pack. I hope your motor/drivetrain are intact (I thought they're sealed) in which case some other brand of ac controller/throttle may be all you need to get this puppy back on the road. All the best!

Here's all the videos I've done so far on the car.

http://www.youtube.com/playlist?list=PLmHss3DBZUikU6Iae3UlaNH73UojlDIkM

Yesterday, I cracked open the motor controller to take a look inside. There was salt-water corrosion inside on the battery connections, but the rest of it looked fine. All other copper and electronics was clean.





My friend, Tom, is an electrical engineer and knows WAY more about AC drives than I do. I'm planning on having him stop over with a known good VFD. We can run that from wall power (240VAC) and if the motor is good, we should be able to control the motor directly and spin the wheels with the car jacked up in the air. At least if we can, we then know that the motor itself is good, and can work from there. Having all the little circuit boards in this car ruined means this car can't be fixed just by replacing the battery. I think it would still make a good "sleeper" conversion, or if nothing else, the body is in perfect condition, and could be sold for parts.

Thanks for the update. I don't know if you've noticed or not, but there is a vent on the motor that goes up near the access lid. It would be a good idea to move the vent down to the ground and see if any water comes out of the motor.

You could also lift one rear wheel off the ground (with the front wheels blocked so it won't move), put the car in any gear as long as it's out of park, and see if you get any voltage from the motor when you spin the wheel.

What shape is the car itself in? Where all has it rusted and how damaged is the interior?

The car body and frame are actually both in really good condition. Rust only happened in places that are normally NOT painted. For example, under the front seats, the mechanism that lets you slide the seat forward and back is rusted up. The steering column has rust, but that doesn't effect it's use at all. The key was in the ignition, and the action of the different metals seized the key in place. (Although the ignition turns, you just can't pull the key out.)

There is also silt in many places, but that is washed off pretty easily for the most part.

The interior is in good condition overall. I pulled out the back seat, rinsed it, air-dried it, etc.

What are your plans with the car? Take a wrecked i-MiEV and transplant the electronics? Siai47 did something similar; the only thing was the airbag controller had a deployment recorded (though I don't think any airbags actually went off) and encoded VIN meant a new one was needed.

Did any of the cells survive?

There are tons of places on the internet that will reset your airbag controller for $75.00. When I was looking at a wreck to transplant some of the front end parts from my "donor" car, I needed the controller. Not only is a controller from the dealer $$$$, there was only one available in the US. I found at least two different places that would do it, both the same price. Unlike GM and some others, the Mitsu controller isn't potted and therefor easy to repair and clear.

All the cells are totally shot.
I've thought of the idea of getting a wrecked iMIEV and transplanting the battery and cards into this body, but the few wrecked auctions I've found, the cars have gone for SHOCKINGLY hight prices.

I guess I'm still trying to figure out the highest and best use for this car. For now, doing a post-mortem and showing what I find is pretty fun.

Yesterday, I got the motor controller out. Once it was out, I could flip it over and remove the bottom cover. Yup, that side was soaking in ocean water. My friend, Tom, came over and brought a small variable frequency drive with him. We were able to spin the motor with it, although not very fast, and it thought it was pulling more amps than it should have.

https://www.youtube.com/watch?v=HDd7wzBJKP0

Here's the latest video and photos on my blog.
http://300mpg.org/2014/07/22/imiev-spinning-the-motor/http://300mpg.org/2014/07/22/imiev-spinning-the-motor/

I'm no expert on circuit boards by any stretch, but I think that if you could clean the motor controller out very well with distilled/deionized water and alcohol, it may still work. The main contactor is inside the battery pack, so no high voltage should have reached the controller while it was underwater, unless the contactor was shorted while the battery still had power. Also, I don't believe any 12 volt power gets to it either while the car's off, but you'd probably know more than I would just because you've seen the wires plugged into it. I don't hold any hope for the charger/DC-DC converter, but the motor controller may have a shot.

Also, what was the draw on the motor while it was spinning? Your frequency may have been way too low for this motor. Even crawling at 1 mph, the motor is making a much higher pitch noise than that.

Variable frequency controller?

You did not feed some music into a pa system (100 volt system like in railway stations?)

I guess the controller is a mess and wants to talk crypted CANBUS to the ECU and the ECU wants to talk crypted CANBUS to the BMU in the first place.

Feeding the motor from a different controller is the right way to go. Each motor has its own encoder. The encoder tells the controler the position of the rotor so it can maximize torque. You can fake the encoder - with pop music if need be. Maybe that is what we heard.

Finding the i-MiEV encoder on the motor and making that one compatible to the controller (Arduino?) would be my next step.

Maybe differential and gears need cleaning and getting rid of salt and corrosion. As far as I have read BMU, ECU and motor controller are married. You cannot exchange one of them. They have to stay together.

On the other hand this car might be the donor for yet another conversion with most of the work already done. Maybe the motor gears and differential can be saved. So it is another controller and batteries. Naive me might try a bike controller for the first ride. 2 kilowatts might run this car some 40 kilometers per hour if it is not up the hill.

Cheers
Peter and Karin