BMW i3 Range Extender (REX?) - United States

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MarkM

New member
Joined
May 7, 2015
Messages
3
Greetings!

I have had a test drive and I was intrigued enough to set up an extended test drive that I will start on Saturday here in Boulder Colorado.

I have a couple of questions that I can't seem to find the answer for. I wonder if the kind people here would be of help:

1. The range extender kicks in around 6.5% battery in the US version. The range then of the vehicle is 50 miles approx based on using the gasoline (motorcycle) engine. Question--if I want to go more than 50 miles can I just add more gasoline or is the act of using the gasoline engine draining on the car battery? I heard that the motorcycle engine would only engage when the car is in motion.

2. I really fancy the ability that the European owners have in being able to engage the range extender as they like. Is there any way by either a chip or some sort of underground software update that would enable this feature in the US?

3. I am concerned about the resale value of the vehicle after 3-4 years. Is that a concern you share?

4. Tesla has been pretty good about providing upgrades along the way to Tesla owners. I believe it is possible to exchange the batteries for 'better' ones though I am mistaken. Has BMW made any comments regarding the upgrade ability of the car over time?

5. How accurate is the range indicator overall in your experience?

6. Are there changes planned for the 2016 model that might impact a buying decision regarding range or functionality?

I appreciate any thoughts on these questions.. :)

-mark=
 
1. THe REx never drives the wheels, it charges the batteries. As long as it has fuel, it will generate electricity. NOw, it is only a 34-hp motor, and while that is fine to maintain, on average the battery charge once activated, if you tried to drive up a long mountain pass with it running, you'd run out of charge and the car will warn you and functionally slow down...it won't stop, but it definitely can slow down...it's not like running out of fuel on an ICE, but essentially, under high loads, you can draw down the batteries even if the REx is running. The REx generally, will turn off when you stop, but not if the SOC is really low.
2. This can be coded by the individual, or you can buy the code and put it on a USB stick, and that will do it. Neither of those are supported by BMW, but enable the generic functionality.
3. If you're really concerned, lease it.
4. This has been discussed, but not sure there is a business case for it. IF there ends up being one, it will happen. The battery modules (there are 8 of them) can be swapped out in about a half of a work day. It is not like unbolting the Tesla pack and replacing the entire thing. The battery pack housing in the i3 is structural.
5. It is working off of the last 18-miles you have driven...if the future miles are exactly the same under the exact same conditions, it can be quite accurate. What does work probably better is to look at your miles/Kw, and knowing the size of the battery and where the gauge is, get a fairly accurate guesstimate on remaining range.
6. Nothing has been announced...we are not all that far into the 2015 model year. Probably by September at the Frankfurt Auto Show, you may hear something.
 
Thank you for the reply!

1. Does this mean that you really can't get strandedas long as there is some charge?
2. Can you link to where you can get the software? Has any one done it here in the forums?
 
So long as you are not depleting the battery pack faster than the REx can re-charge it then you will not be stranded. If you do deplete it faster than the REx can re-charge it, you will experience a sort of "limp-mode" where the vehicle will have greatly reduced capabilities, but no, you will not be stranded.

If by getting the software you are talking about coding, yes, lots of coders out there. I coded my car an hour after I bought it, now at any point I am below or at 75% I can manually turn on the REx and attempt to "hold state of charge" again, this only works if you are not depleting the pack faster than the REx can charge it. Coding also can allow you to unlock another 0.5gal of capacity in the fuel tank. Between REx and the battery pack my car showed 180 combined "estimated" range this morning in Eco Pro +. The day I bought my car I drove it home 425'ish miles, after the initial 100 miles I stopped about every 60-70 miles for about 2 gal of fuel. I got home with 22% charge left and about 1/2 tank of REx fuel. I ran at least 65 with the AC on the whole way.

Good luck!
 
If you don't want to learn how to code the car, DVDINMOTION can provide the software patch to enable the REx like it is available elsewhere. CARB rules had BMW choose to implement their restrictions for all cars sold in the USA for the credits. The car itself doesn't care, it's all controlled via software.
 
Use of the search function at the top of the page results in dozens of hits for dvdinmotion...... Lot of threads with lots of information.

BTW, unless your i3 has the Professional Navigation System you will have to learn to code and buy some cables: dvdinmotion's patch won't work on the basic Nav.
 
MarkM said:
Greetings!

I have had a test drive and I was intrigued enough to set up an extended test drive that I will start on Saturday here in Boulder Colorado.

I have a couple of questions that I can't seem to find the answer for. I wonder if the kind people here would be of help:

1. The range extender kicks in around 6.5% battery in the US version. The range then of the vehicle is 50 miles approx based on using the gasoline (motorcycle) engine. Question--if I want to go more than 50 miles can I just add more gasoline or is the act of using the gasoline engine draining on the car battery? I heard that the motorcycle engine would only engage when the car is in motion.

2. I really fancy the ability that the European owners have in being able to engage the range extender as they like. Is there any way by either a chip or some sort of underground software update that would enable this feature in the US?

3. I am concerned about the resale value of the vehicle after 3-4 years. Is that a concern you share?

4. Tesla has been pretty good about providing upgrades along the way to Tesla owners. I believe it is possible to exchange the batteries for 'better' ones though I am mistaken. Has BMW made any comments regarding the upgrade ability of the car over time?

5. How accurate is the range indicator overall in your experience?

6. Are there changes planned for the 2016 model that might impact a buying decision regarding range or functionality?

I appreciate any thoughts on these questions.. :)

-mark=

MM

Just a few additions. The only situation I would be wary of are large inclines at highway speeds. I have driven with the REX chugging away on smaller roads with steep inclines and did not have any ill effects. If you are ever caught in that highway hill situation, you could pull over and the REX will run until your battery is back up to the 5-6% or so. I think the USB upgrade helps because it eliminates this anxiety on road trips. Incidentally, I could not really hear the REX at highway speeds since it is drowned out by wind noise.

Regarding the resale value, 2016 prospects, and battery replacement. I think a great option is to shop around and try to lease a 2014 at a discount price. They are essentially unchanged with the exception of DC fast charging and heated seats standard which most 2014s already have. I personally think the residual values on current leases are "generous". I can see used 2014 i3s being sold in the 20-25K range in 2017. If this is true and you intend to sell your car after 3-4 years, leasing may make more sense than buying.

If you are intending to buy, (I still would go for a 2014 at a discount), you do have a long battery warranty 8/100K. Given the cost of a battery replacement, I think this would only make sense if you have driven your current battery into the ground and need to replace it after many years. Usually, you would be looking for another car by then and probably not overly concerned with resale values.

Good luck.
 
Once the battery pack reaches what BMW calls end of useful life IN THE CAR (it cannot hold 70% of original full charge any longer), it still has lots of uses elsewhere, so it is not worthless, and there SHOULD be a decent value in it you could use towards a new one, if you wanted to. That would help with the exchange costs. Consider that a larger battery pack that may be available down the road would then take longer to fully recharge, since you'd not be changing the charging circuits. That may or may not be an issue to you. Given that the car is essentially plastic and aluminum, it shouldn't have rust issues, and you could keep it a very long time should you choose. On any car, that maximizes your value, since the depreciation gets spread out over many more years. With an interface kit, that battery pack could be used as a power backup unit in your home and probably power it for a day or more, depending on your typical uses. Nice to have backup. Once these things start to show up on the market as used battery sets, I think you'll start to see some options to continue to use them. BMW has announced some plans along those lines, but more on a commercial side rather than residential.
 
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