I've been hearing on and off about how the generator/engine in the BMW i3 REx does not have enough spunk to maintain battery power on an extended climb - and recently there is now a lawsuit about - well whatever. So let me add my real world experience to the mix.
The drivers that reported this were mostly west coast and had access to long climbs over mountains, the i3 would literally go into a 'limp' mode, shut off items not needed to reduce power and slow to 40 or below. I have not heard any reports of issues on the east coast though, if it did happen it was brief or no issue at all. It could be that the east coast just does not have long steep climbs near where i3s roam....until now.
Finally I had the opportunity to give my i3 REx the climb test, up in the Catskills of NY, 125 miles away from my home is a 3.5 mile 2,000 foot climb on the way to a family vacation house, I was going to make it even more exciting by having my i3 filled to the brim with luggage and family.
One way the trip is about 130 miles along a fast highway where 75 is the norm, Rt 87 or the NY State thruway, and finally ends up on the top of one of the Catskill mountains near Tannersville NY. This trip is before the DCFCs were installed along the rest stops on the Thruway and just around the time , the town of Kingston installed 9 Level 2s, With that in mind since I wanted to stay on battery power as long as possible the plan was to drive from my home and stop over at BMW NA in Woodcliff Lake for a quick boost on one of their DC Fast Chargers and hopefully have the REx turn on just as we are done with the highway drive, meaning I'll have plenty of fuel to to make it the rest of the way for the long climb and anywhere else we needed to go once on top of the mountain since gas stations are not as frequent up there. I should mention my i3 is NOT coded, I'm all original.
So I pack up my i3 load up my family and we are off. I'd like to add that the i3 was really weighed down but still rode very composed, I was really impressed. The i3 suspension engineers did their homework with this one.
|My i3 REx loaded up, drivers side seat was even folded down holding more stuff|
First leg of the trip was as expected and I arrived at BMW NA without issues, range was down a bit with the heavier i3 and AC was on but not bad at all.
|Not bad range considering AC on, highway and a loaded up i3|
I usually head to the first northern building, there are chargers throughout the campus but this is one of the ones I'm more familiar with - there is a bank of level 2s and three DCFCs.
|Pretty empty except for what I guess is a company i3 parked in one of the DCFC spots not plugged in - though there is access to that DCFC from either of the spots along side|
You need a ChargeNow account which is basically a ChargePoint card but make sure it is activated for ChargeNow....these units here at this location are currently complimentary which is awesome of BMW. You simply swipe your card to unlock the plug and your off charging.
|Getting the DCQC (some say DCFC) going is easy enough|
|It is a big plug and you must swipe your card again to end the sessions and unplug it|
Once the i3 and the Fast Charger connect the magic of charging faster than a Level 2 begins. Now these units up at BMW are not the 50kW monsters you may have heard about, these hum along at 24kW, but that will still get you a nice boost quickly. Remember at home you are probably getting between 6 and 7kW and on public Level 2s it will be even less so 24kW is quick. I saw 22kW to 23kW steadily......nice.
|That was quick - I was around 46% when I arrived and in about 30 minutes I'm almost full|
|Notice the SOC - at this point the charger begins to throttle back to protect the battery|
|Bummer...at least I got almost 95%|
....Fault.....I received a charging fault at around 95%. I have seen this before and it appears to be random so I just left it as one of those i3 hiccups and it could have been the DCFC charger itself. Hard to tell, I could have used one of the nearby L2s to finish the charge but I had enough now to continue the trip.
|The DCFC would not continue but I probably could have used one of the nearby L2s - the DCFC also shows me an INTERNAL FAULT message on its own screen|
|My Wife...waiting to get going - like stop taking pictures...Daughter is inside keeping cool|
And now its climbin' time. We get off at Saugerties, the REx is humming along fine after about 10 miles of use, we drive another 9 miles to Palenville, the base of the climb. The altitude is just under 400ft there and the final destination, about 8 miles away is 2,700 ft. That does not sound so bad but 2,000 of those feet happen in the first 3 miles and the last part of those 3 miles is the steepest part - it is also a constant climb.
|Just over a mile before the climb - a full tank|
I like the navigation in the i3, it shows a nice display of the impending mountain range that I'm about to tackle. It's all 'uphill' from here on to the house.
|On the Nav - here we go|
I was sticking to the speed limit which can float between 35 and 40mph, I had AC on. I passed one slow bus by giving more REx induced juice and then throttled back once I passed - cost me about 1% according to the SOC - still I'm not worried. I would throttle back whenever I could to give the REx time to catch up as I noticed my SOC dropping. The REx was giving it all it had, if you thought it was loud under normal use you have heard nothing yet....you could really feel it too. It was not terrible just noticeable by everyone in the i3 and this is mostly because the i3 is so darn quiet and smooth most of the time.
|Early on I passed a bus, not problem|
SOC continued to drop slowly, but I knew of a less steep area coming up and I could throttle back a bit to let the REx catch up...so I thought. As I began to throttle back so did the REx....what?! Yup, even when the SOC dropped to 2% it the little engine throttled back when I did. I had no way of catching up....this climb was starting to get interesting, to say the least, and we were just getting started.
So back to it...half way up things were getting a bit more anxious, SOC was dropping, and the REx still was not taking advantage of the areas where I could use less juice...and the steepest part of the climb was about to begin....the power reduction warnings were becoming more prominent. The only way I could catch up on SOC was to slow down, a lot, though I still had the AC on because I wanted to keep the family comfortable especially since things were heating up in the cabin - so to speak.
|2% is kinda low - REx is really trying....does it have enough..power bars still there|
At this point I was really glad to have the SOC readout because I could gauge how close I was to needing to really slow down and/or turn the climate control off to conserve whatever power I could.
|1%......I would welcome 2% now|
Below 2% was when the power bars began to fade though even at 1% and the loss of some power bars the i3 still had enough power to keep with traffic and for me to have the AC on....I was thinking we might make it without having to slow down. The steepest part of the climb was now in view, the REx got a little louder, the SOC charge dropped the .5% - that's point 5. This was going to be a nail biter, and it was. The the little REx finally said had enough and told thee computer to take over and reduce power even more as well as shut down any other items not deemed necessary like climate control.
How many of you have seen .5%? I'm thankful that that part of the road dropped to 35 and there was a slow lane I could pull over to. The REx was screaming but I was able to maintain 35, though I had the accelerator floored. I was not sure we would make it but we did.
Bottom line...we made it, the REx definitely did it's job, it would not have stranded us but there is no doubt that the power reduction warnings then the reduction in power can be a bit nerve racking the first time. I made this trip 3 other times and even with just me in the car, no AC and taking it a bit easier the i3 still experienced a reduction in power at the steepest part of the climb. So is the i3 flawed or dangerous, no. This climb I take is challenging for any car and BMW never said this little engine was capable of extreme trips, it is just a tiny 2 cylinder and common sense dictates that its not designed to function like a motor built to drive a 2,800 pound vehicle. With that in mind there is room for improvement and that would be to allow the REx to continue to rev so as to catch up. That could be a software update
Again I did not get stranded and the i3 kept to the speed limit but the warnings, reduction in power, etc, definitely makes for an exciting drive. Since this particular trip I did this climb 2 more times with the same result each time - it ran out of breath at the top, nearly the same place, even if I took my time and had just me in the car. So now I know the spots where I will HAVE to slow down. Again I want to stress the i3 got me to my destination, it even kept us at the posted speed limit, BMW never said this engine could climb mountains nor is it designed to do so, this is a steep climb that challenges even ICE cars. With that said, the average user might be caught off guard here, I knew what was happening but my Wife did not and looked noticeably nervous.
So what is going on....I'm no engineer but this is related to efficiency. The i3 is no Volt, meaning it's motor or generator is not designed (robust enough) to drive across country nor does it have a HOLD feature so I could have run on the REx along the highway then use electric for the climb. Why there is no HOLD feature on the i3, unless you code it, is so that our little i3 can qualify as a true EV, I'm ok with that as I did not have to pay sales tax in NJ because of that, the Volt you pay tax. It's all EPA this and that, not something I'll get into - it is what it is.
With this climb the biggest problem was the fact that the REx throttled back when it detected I needed less juice to keep going, instead of taking the opportunity to stay rev'd and add more juice to the battery. There is a rumored adjustment, not a fix as I think it will be similar to what we have but the software will be updated to play better on climbs, that will keep the REx revving longer. Additionally for those experienced REx users when the REx initially turns on it won't drop to low SOC before it settles into its routine.....this is what is expected in an update which is delayed. That rumor bouncing around that the REx will detect a long mountain climb on the navigation and rev up to prepare for it is strictly a rumor and most likely misinterpreted info from BMW. I can say with certainty BMW is aware of what's going on and is looking to make it better without jeopardizing current EPA compliance.
I think that is what this rumored software fix is supposed to do....keep the REx revving all the way to 12%...who knows. It was said the Nav would detect a climb coming up and the REx would prep....whatever it is clearly the i3 needs more than 6.5% in the pack during a climb for the REx to make it.
The characteristics of the REx made for the next 5 miles of climb also a bit hairy....because it would not stay at full power, even on the flat parts the batt never had a chance to recover. I was triggering the power reduction warning and losing bars for the rest of the trip. I can't imagine what a newbie EV driver would think. With the REx screaming as much as it did my mpg dropped to about 20 overall.
|Finally made it.....hmmm....MPG not so good ;)|
So we finally made it, wow that REx was spewing hot air out of the back. All the fans were going...Serenity needed a beer just like me. I quickly took in the view...amazing up here but a barren wasteland for EVSEs.
I had to do Level 1. I had just one accessible plug outside on the stand alone garage, houses up here are old, fingers were crossed and...uggghh....GFCI fault. So I set Level 1 charging to lowest and that held though it told me it would not finish charging until next year, plus, I had to share it with an active golf cart. That was just not going to do, I need a faster charge as I wanted off of the REx. I knew that a nearby skiing resort had a charger.
|Plugged into the only outside outlet at the house|
|Wait your turn|
|GFCI fault - older wiring|
|It is beautiful up here but a barren wasteland for EVSEs - somewhere out there was an L2 at Windham|
Because I had no cell service or internet Plugshare was unavailable but thankfully the i3 Nav had charger locations in its database and the ski resort came up, Windham Mountain...bonus. It was 12 miles away and was 9pm.....I'm going for it, feels like the early Mini E days. I remember seeing it on plugshare years ago but then it was turned off, though it seems to be back, at least according to BMW data - sure hope it was current. I made a call ahead just to be sure it was there but the person on the phone did not know much about it, just they had one somewhere on the property - gee, that's like 1,000 acre property...pounded my chest and was off My Dad wanted to join me to see how a real EV pioneer lived....was happy for the company.
I'm driving along the gorgeous mountain and valley roads and what do I spot parked at a very secluded Inn? Another i3....Unicorns are less rare up here...whoa!!!
|Whoa....another i3 and Unicorn color too|
|Grabbing a photo opportunity|
We talked a little more about our i3s and then I was off to find this oasis of a charger at Windham. As I entered the Windham property the GPS took me through the entrance that leads into the lower ski parking lots which was like an off-road baja course this time of year. I was getting a little anxious and then there they were, sparkling in the moonlight right in the middle of the main paved lot.
I am happy to report the Windham chargers are really accessible. Right in the middle of the main lot in front of the main lodge. Dual ChargePoints and complimentary. There is 24/7 security and the guard came out to make sure I was charging ok.
|Chargers are in the middle of the main lot|
These commercial units must be at 240v because I went as high as 6.8 on the kW speed, I was charged up enough in a couple of hours.
|This public charger was humming along|
|Great night to charge an EV|
It seems the i3 protects its battery from over charge, during heavy regen it never let me get past 98%, only once I slowed down to flatter areas with less regen did it hit 99%. So if the i3 was not letting the battery recharge how was I able to regen, well it seems the i3 uses its friction brakes to simulate the regen. It is pretty seamless and hard to detect....very clever. Only one drawback of this technique....hot brakes....when I got to the bottom of the hill you could smell my brakes cooking, quite odd in an EV but there you are. I've been told by a reliable source that if I left off the throttle quickly twice the friction brakes will disengage, have not had a chance to try that yet.
So what now? It seems there is no getting around that the REx just can't get me up the mountain without a struggle, granted it does get me to my destination and that is key but as a driver you have got to be ready for a loss of power. I find it is a serious flaw that the REx lets off revs as soon as I let off the accelerator, I am sure that is to give the little engine a rest but it does not help on a long steep climb.
Anyway, lucky for me (at the time of these trips) a better solution had appeared. In the town of Kingston NY some 15 miles before my climb they have just installed 9 Level 2 chargers. All I needed was an hour there and I'd have enough juice to get at least half way up the mountain, the steepest and fastest parts on battery power, and then the REx can then take me the rest of the way. The town had a really nice downtown full of shops and restaurants just one block away from the chargers.
|Shot of me using the Kingston chargers - that's the Mayorial (at the time) candidates Focus EV next to me ;)|
I made a few more trips up that mountain last year, tried a few other techniques like no AC or no other people in the car but had the same results. I even passed on the opportunity to boost up at BMW NA along the way...after all the REx is rated for 150 miles total and I had 130 to do....yeah, that was cutting it really close with the long climb. At least I now have that L2 at the top waiting for me so charging up quickly is possible.
|This was a couple weeks later during a special moon - L2 at the house would be installed the following week|
|A trip I took when where I did not stop at BMW NA for a boost along the way.....yeah, was sweating a bit especially since I had 4 more miles to go...all up hill...never again|
At the end of the summer the L2 was finally installed. JuiceBox Pro 40...yeah!
|Finally on an L2 - JuiceBox Pro|
One more thing, after driving on the REx for long distances I would get that glitch of a drive-train error, but only at home in NJ, did not happen in the mountains, altitude maybe, it was not dry up there but who knows. Just another i3 mystery
|My welcome home message|
Update: there is a fix for the above, just had it done in May and it has not returned.
This past July I made the trip again to see if the fix and new software updates made any difference...no. Same results and this time down to a tiny bar. NOTE: the i3 did not strand me, it did what it was supposed to do and got me to my destination. Is this reduction in power a fault of the car? I think not, it's a small motor, and is tuned in a way to meet CARB credits. Can BMW do more to inform the consumer of the possible reduction in power - yes. I know it's in the manual but more should be done, maybe a sticker on the dash at time of purchase like the airbag stickers or hang tags.
|Down to 1 bar|
|Really odd - REx turned off while I was parked and I'm at 3.5%|