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Monday, April 1, 2013

It's All About The Range....Extender

Now that I have the added hardware, I've re-badged the car as well. 

One of the differences in the MINI-E and ActiveE trial lease programs is the ActiveE lease is more of a traditional automobile lease, where the MINI-E lease was specifically crafted as a beta test program and there were very strict rules. We were not allowed any modifications, we even had to get permission if we wanted to tint the windows. One person was actually thrown out for adding a simple modification that BMW didn't approve of. Now with the ActiveE, we can basically do what we want to as long as we return the car in good condition, and undo whatever modification we have done. Of course we can't do anything that is unsafe or that would be permanently installed so that you couldn't uninstall it, but short of that we pretty much have the green light to have fun.

You can see how much room is up there
I like that BMW is going to offer a small gasoline engine as an option on the i3 to extend the range. It won't be something everyone wants, but those that do can now buy the car without worrying about ever running out of charge and getting stuck somewhere. It will also help in the winter months in cold climate areas where the range drops and make it possible for the owner to complete trips that they wouldn't  otherwise be able to. I've been kicking around the idea of installing a small gas generator to my ActiveE for a while now, basically for emergencies but also for those occasional days where I need a little more range. I then stumbled on a small affordable generator that looked like it would fit perfectly in the empty space under the hood of the ActiveE, in between the front battery block and the fan. It's basically a huge empty space up there, big enough to fit a small suitcase.

The manual is a must for any modifications
So after I confirmed the dimensions would work, I picked up the Ryobi 2200 generator and the project began. Everything was very straight forward, the unit fit perfectly in the space up front and all I had to do was secure it so it wouldn't bounce around and damage anything. The only hard part (and it wasn't really hard) was I had to connect it directly the the KLE(onboard charger) above the power electronics and motor because if I didn't the car wouldn't run while it was charging. There is a safety feature in today's electric cars that don't allow them from turning on if it's plugged in, whether or not it's charging. By circumventing the whole J1772 charging port and connecting the power supply directly the the onboard charger, the car would start and run while it is charging without any issues. I happen to have the full technical manual for the ActiveE so this was not a problem. In fact, I offer the manual for sale on my ActiveE Modification website. It's $19.99 and can be downloaded directly from the site upon payment. The manual is a must for anyone that wishes to modify their ActiveE.

Running the feed from the generator to the KLE
I'm not going to show detailed pictures of the completed set-up or offer instructions on how to do this because I'm concerned about liability(and BMW coming after me for instruction people how to modify their cars) but if somebody is really serious about doing this then contact me directly and I can offer advice on what not to do. All you really need to do is run your supply line from the generator to the KLE and figure out how to connect it. It's literally a three hour job if you know what to do.

I had to install a carbon monoxide detector
I've had it installed for about a month now and it's been working perfectly. Since it's a small generator, it only adds about 6 miles of range per hour. It helps, but certainly doesn't allow for continuous driving. What it does do well is charge the battery while I'm parked for a while. If there are no chargers around and I go shopping or to a movie I can just leave it running and it will charge the car up. That has two minor problems though. First, it's really loud! People walking by really stop to try to figure out why the car is running and way it's sounds like a lawn mower. Secondly, I didn't route the exhaust out anywhere, figuring it would just escape through the seams and underneath the car. When it's on while I'm driving it's no problem, but if I leave it charging while the car is parked for a while, the cabin does get infiltrated with a fair share of fumes. Just to be safe, I installed a carbon monoxide detector inside the cabin so I can monitor it. It is quite startling when it goes off as it's only inches from my head but all I need to do is open the windows for a few minutes and it shuts off. 

Running the genset before permanent install
It really is doing exactly what I had hoped. By running it for a couple hours while the car is parked I can easily drive 110 - 120 miles per day. I know it's kind of cheating using gas and all, but sometimes you just need a little more range. I wish I had this last year when I ran out of charge a couple miles from my house and had to plug in at a Burger King and wait there an hour! Now that I've conquered this I've begun to experiment with a larger generator, one that could add 20-25 miles of range per hour. Of course this large of a generator wouldn't fit under the hood, and would need to be towed on a trailer behind the car but would allow for much longer drives if I wanted to. So I went out and bought a big generator and began to tinker with it. Surprisingly it didn't work instantly like the smaller generator did and I'm not sure why. I even broke out some EVSE's to test the generator charging the car and using a (supposedly) wall mounted EVSE. It got even more interesting when the ClipperCreek EVSE wouldn't charge the car but if I hooked it up to an AeroVironment unit it would. I'm still working on this but I'm sure I'll figure it out. Then all I need to do is get a small trailer to pull the generator. I've already welded a tow hook to the frame of the car behind the rear bumper so it's good to go.

Testing the larger genset with two EVSE's

I figure I'll have this done in a couple weeks and will do a post on it along with video of me driving the car with the trailer and the generator running. Feel free to post questions and comments below but please don't ask me anything specific about installation here, I can't post that publicly. Below are some assorted pictures of the REx experiment:

The ActiveE trunk once you remove the carpeting. The KLE is directly behind the shiny metal door in the center. You simply remove the eight Torx screws and it's sitting right there to connect your supply to.
Snaking the yellow cable from the engine bay to the KLE took the most time. I used a heavy duty 10 gauge outdoor wire and made sure it didn't interfere with anything. 
When I connected the large generator directly to the KLE I used a very heavy gauge high voltage outdoor cable. I'll eventually route this under the car up into the power electronics area before attaching the trailer.
The lighting isn't good, but this view is looking up into the motor assembly. I routed the cable up through here.

The tow hook is ready to go, all I need is a trailer now!

The REx tags are all over the car. If you got it, flaunt it!
UPDATE: For those that haven't figured it out yet, this was an April Fools post. I haven't added a range extender and I don't have an ActiveE modification website. I hope you all had fun with it - be well!


  1. Love it! Well done, Tom!

  2. Lots like the large genset already has a nice set of wheels. Why not hook it up as is. It should be good up to 70mph. If it does come lose the orange cable will stop it firing off into the other lane of traffic.


  3. It's a good think you used the carbon monoxide detector. I would hate to hear of your demise ;)

  4. I'm thinking this might be something BMW doesn't approve of! Check your driveway this morning for the tow truck! lol

  5. Greg,

    I looked into that but those wheels are only rated up to 40mph and I'd like to take this on long highway trips like to Florida or Maine so I would want to drive faster than 40mph. Good thinking though, thanks.

  6. Tom,

    Did you consider using your BMW contacts to "borrow" one of the i3 range extenders? I suspect it would fit in the ActiveE's trunk, and you could find someplace to put the fuel tank.

    I did some research on the i3's range extending ICE when it was first announced that it would be a 650 cc engine from BMW's Motorrad Division. It has now been officially revealed that it will be the same engine found in BMW's C 600 Sport and C 650 GT maxi-scooters, tuned of course for driving a generator at a single speed.

    The impressive 2-cylinder 647 cc Motorrad engine is all-new (2012) and reportedly the most powerful and efficient in its class. It is liquid-cooled with 4 valves per cylinder (double-overhead camshaft), producing a maximum of 60 hp at 7,500 rpm. The i3 range extender would not need nearly that much power, and has been rated for continuous operation at a much lower rpm.

    The engine has a 79 mm x 66 mm bore and stroke. In its motorcycle application, a stainless steel exhaust system is used with a closed loop catalytic converter satisfying the EU-4 emissions standard. It is electronically fuel-injected and uses a dry oil sump, with the oil tank integral to the aluminum engine casing. Both oil pump and water pump are driven by the bottom balance shaft via the spur gear. The quantity of coolant is 2.2 liters; oil capacity is 3.1 liters with filter change.

    The engine, as expected, has a very low acoustic and vibration signature, resulting from an innovative design, which includes a 90° crank pin offset, 270° ignition spacing, and two balancer shafts driven by spur gears. The oscillating inertial forces are eliminated by a system of articulated joints, positioned centrally on the crankshaft, comprising an arrangement of counterweight masses. Apparently it all works vey well indeed.

  7. Tom, it just gets better and better, Your range knows no limitations.

  8. Thank you Peder. Of course for you I'd offer all the details if you wished to do the same! :)

  9. Tom: I ordered the service manual from your activee modification website and I'm very happy with it! Thank you for offering this information. I wouldn't dare do any unauthorized modifications without it! By the way, do you know where I can score some of those special batteries you installed last year? I promise not to tell ;)

    1. Thank you for the business Ed. I can't help you with the "extreme batteries" they are not available anymore due to the high risk of thermal runaway inherent in them. Did you also receive the free EF-OPEC T-shirt with your purchase? We were giving them away to the first 100 customers that bought the manual so I hope you got it.

  10. The carbon monoxide detector is priceless. Is that photo-shop or did you really stick it to the headliner?

  11. Not going to be fooled for a 3rd straight year ;-)

    Though, have to say that two April 1 posts by you, the i3 test drive post -- -- and the post here, above, began to make me wonder a bit if your i3 test drive was for real ;-)

    1. So what you're saying is I did at least have you thinking about the i3 test drive? That's good enough for me Christof!

  12. Replies
    1. Ari: I wouldn't need to do this if NYC installed MORE PUBLIC CHARGERS! ;)