(Update: I bought one!) Test Drove 2016 BEV w/ 34k miles. Battery Check?

[slsrs6]

Went to test drive a 2016 BEV model today. 36k miles. I went in and checked the battery kapa and it said 17.3 kWh. It was fully charged and I was getting ~65 miles on the GOM and 90 in Eco+ mode. Is it really possible to get 80-90 miles if you drive gently?

I already drive very gas-conscious. 65 on the highways and coast as much as I can, very easy acceleration. I drive a 5.0 F150 and my game is seeing how high I can average for MPG lol (21+ right now). Just wondering what -realistically- I can expect from the battery on this? 60 miles? 70 miles? 80 miles?

I live in FL too btw, so we rarely get a cold day. I live close to the ocean so it's more temperate than inland. 80-90s in the summer.

I've heard people saying 50 miles pushes it, but then they also say they drive 95 on the highways :roll:

With my driving style, what can I expect do you think? I really do love the car! If I could get 70-80 miles with some very gentle driving I'd be all in..

 

[websterize]

~65 miles max. That sounds about right: 70 miles = 4 mi/kWh x 17.3kWh. You'll see 4 mi/kWh at speeds under 65 mph, with gentle starts and stops, and in Eco Pro driving mode, which changes acceleration mapping and reduces the output of the HVAC. In EcoPro+, the car goes into Apollo 13 mode, disabling the A/C. In Florida summers, you want to avoid EcoPro+. This mode also governs speed to 56 mph — yes, you can defeat it with a hard press on the go pedal or ACC/DCC — so you'd be sweating and going slow simultaneously. In extreme temperatures, especially "cold" weather (<50ºF in the Sunshine State), plan on a range of ~50 miles = 3 mi/kWh*17.3.

For road trips, winter or no, I'd probably take the truck. For other common outings — groceries, eating out, going to the beach — this is the perfect car. And the BEV requires virtually no maintenance, just brake fluid every two years and tires. I'd buy it.

 

[slsrs6]

Hey thanks for the reply! So when you say "65 mile range", does that mean most days in I could actually drive 32.5 miles one way and 32.5 miles back home? Or does that mean "65 miles is your range, but in the real world you should only really plan for 50-55 mile trips at most?" Just wondering how accurate these range estimations are. Honestly most of my trips would probably only be 40 miles at most. 80% highway.

What happens when the battery reaches low capacity, say 5-10%? Obviously in a gas car, it runs completely normal until it's completely out of gas. Will the i3 run like normal until it's completely out of charge? Or when it gets low, will it start to limit top speed, slower acceleration, etc.?

Hopefully that makes sense. Thanks!

 

[websterize]

With Florida’s flat roads and moderate temperatures, as long as you keep your speed below 65 mph, you should be fine at 65 miles total. That’s probably the max., though. In your shoes, I’d feel more at ease plugging in at the office, even a 110V L1 plug, assuming you’re thinking of the i3 as a daily commuter.

As the pack’s state of charge drops below 15%, you’ll hear and see warnings. It doesn’t just land in your lap. At very low SOC, the car will go into “turtle mode,” severely limiting speed, before stopping altogether. Then you phone a flatbed.

There are many variables to range. If your plan is to hit the 60Ah max. range often, you might broaden the search to the 94Ah, which easily could do 100 miles year round in Florida with your described driving style.

Good luck — the BEV is a solid car.

 

[eNate]

If it helps ease your concern, I've driven mine to zero indicated a few times. It's very trustworthy, which is why I've done it. The rate of discharge tracks steadily (not like a phone or PC which can go from 15% to "shutting down..." in a blink) .

There's a healthy hidden buffer below 0%, so even upon reaching 0 miles remaining, the car doesn't just stop, it keeps you moving for a little bit longer. We're only allowed to dip our feet into this buffer — the bulk of it is unusable and is there to protect the battery from being completely run down.

The practical side of this is you don't want to make it a practice to go into this territory with any sort of regularity. But it's good to know the i3 can be relied on for the full range of what's it indicates it has available.

 

[alohart]

We live in Honolulu, so neither cold nor hot weather is an issue (~65 ºF - 90 ºF). On warmer days, we use A/C set to 74 ºF. I tend to drive between 30 and 60 mph. I keep our tires inflated 10 psi over the recommended pressure which reduces rolling resistance and increases range a bit. Our 2014 BEV has averaged 5.2 mi/kWh which is higher than average, mostly due to our ideal EV driving conditions.

When our battery pack was new, I could drive ~105 miles on a fully-charged battery pack (the Batt. Kapa. max value was as high as 20.9 kWh). Unfortunately, the usable capacity has decreased by ~20% from the nominal new usable capacity of 18.8 kWh despite having driven less than 12k miles. Ours isn't the only 60 Ah battery pack whose usable capacity has degraded by such an extent which is why I recommend avoiding buying an i3 earlier than a 94 Ah 2017 model. 94 Ah and 120 Ah battery packs don't seem to be degrading as rapidly as some 60 Ah battery packs. Because not all 60 Ah battery packs are degrading as rapidly, I suspect that 60 Ah battery cell quality wasn't as consistent as later cells. The performance and capacity of an i3 battery pack is that of the weakest of its 96 series-connected cells, so if only 1% of the cells in a battery pack are weak, the entire pack is weak.

There's no direct way to measure the charge level of a battery pack while driving. Even when parked and not charging, the battery pack's voltage isn't a precise indication of charge level over most of the charge level range. However, at high and low charge levels, the voltage changes more rapidly as charge level changes The battery management system (BMS) has high and low voltage limits that prevent the charge level from being too high or too low. Many BMS's calculate charge level by keeping track of the current that flows in and out of a battery pack. This calculation can drift over time due to internal self-discharge that the BMS cannot measure. However, when the pack voltage reaches upper and lower limits, the charge level calculation can be calibrated to known charge levels. Several i3 owners have reported running out of energy despite the displayed charge level being > 0%, so it's best not to depend on energy being available at very low charge levels.

I periodically calibrate the charge level by purposely driving until the gray chiclets on the power gauge begin to disappear. This indicates that the usable energy is about exhausted and that the BMS is preserving the remaining energy to minimize the risk of running out of energy and becoming stranded. With 3 chiclets remaining, the charge level of our i3 is typically 0.5%. That's as far as I push it. I do this on a hill above our apartment so that I can regen down the hill to add enough energy to be able to return to our apartment parking space where I can charge our car. Unfortunately, this has never increased the usable capacity of our battery pack as I had hoped that it would do.

 

[slsrs6]

Art,

Are you really averaging 5.2mi/kWh?? FL is extremely flat, and - at least the area I'm in - is pretty temperate 6 months out of the year. If I could average even 5mi/kWh that would give me at least 80mi range in good conditions. That would be very nice indeed. The farthest places I go on a regular basis are about 30-40 miles roundtrip, and a few that are 60, so 80mi would give me a nice comfy buffer for 95% of my trips and make this car very practical for me.

Honestly this 2016 is 6-8k cheaper than any 2017+ models I'm seeing, and it's at such a good price I could resell it in a year and break even (not to mention savings from driving). So I'm thinking it would be a good purchase either way. If the range drops below what I need, I can sell it. If I like it and want to upgrade in a year, the 2017s should have come down in price by then. This'll be a good way to dip my feet in the EV pool so to speak

 

[alohart]

Are you really averaging 5.2mi/kWh??

That's the lifetime average of our i3 according to the BMW Connected app. It was 5.5 mi/kWh in the original BMW i app or whatever it was called. Until 2018, we spent the 6 warmest months at our Swedish apartment and stored our i3, so we didn't use much A/C during our first 4 years of ownership. Starting in 2018, we've spent more warmer months in Honolulu and thus have used more A/C which likely explains the drop in average efficiency. Of course, we've never used heat.

Honolulu is much less humid and not as hot as Florida can be in summer months, and we keep the climate control set point at 74 ºF which is warmer than many people prefer, so the A/C doesn't work as hard here. I've also coded air recirculation to remember the previous setting rather than defaulting to on. I always set recirculation to off so that no warm, humid outside air enters the cabin which reduces the A/C load and increases efficiency. Window fogging is rarely a problem because we have almost no cool, humid weather. Our parking space is in a parking garage, and I almost always park in a parking structure while out, so the cabin doesn't heat-soak very often which also reduces the A/C load.

I always drive in Eco Pro mode with adaptive cruise control (ACC) on. ACC controls acceleration which is quite leisurely. If I can see ahead that I need to reduce speed or stop, I temporarily disengage ACC and position the power pedal for coasting (i.e., no propulsive or regenerative power) which is more efficient than regeneration. I use friction brakes only when regeneration is insufficient to decelerate as much as needed.

Honestly this 2016 is 6-8k cheaper than any 2017+ models I'm seeing, and it's at such a good price I could resell it in a year and break even (not to mention savings from driving).

The battery pack in the i3 you're interested in isn't degrading as fast as ours is, so range is likely to remain as good as can be expected.

Speed and heavy A/C use are significant range killers, so if you can control those, if the price is right, and if the range likely meets your needs, it's probably a good purchase. Be aware that Internet connectivity in a 2016 i3 will cease by February, 2022, so you'd lose the ability to control and check on things remotely via the BMW Connected app, you would no longer have real-time traffic information in the navigation system, you'd no longer be able to search the Internet for navigation destination information, and you would no longer have access to other ConnectedServices that you might want. That won't happen with 2017 and later models.

 

[BL5]

I know the 2016’s price is very appealing to you, but I would avoid the 2014-2016 model years like Art said. The 60aH models seem to take a harder hit long term on range. BMW appears to of ironed out most of the issues by 2017. If you plan on doing any long trips, a REx version is suggested.

Remember, just because the guess-o-meter displays 86mi or whatever doesn’t mean you’ll get 86mi. Plug you’ll have to factor in where’s your nearest charge location. The 60aH BEV model would never work for me, as I like to take longer trips.

I plan to get rid of my 2015 REx by end of the year due to it’s range limitations and get a 2019 REx in its place.

 

[slsrs6]

Well you don't have to worry about me getting a 2016 BEV anymore, cause it sold an hour before I went to buy it :x

But I'm still convinced a 60aH is all I need. It's my second car as I think I mentioned. Really only to commute to work, groceries, etc. and none of them are more than 10-15 miles. The absolute farthest place I'd ever go "in town" is only 19 miles away. I only ever go to straight to these places and come back home. I'll use my F150 for anything out of town, which nowadays is rare for me.

I also don't plan on keeping the car forever. Probably just a year or so honestly. If I develop a love for it, then I'll probably sell it and find a 2019+ that I can use more. But this is sort of a "low investment" way to try an EV car for me. See what happens. The 14-16's have depreciated enough that if I find a really good price I'd feel comfortable selling it for what I have into it in a year. Plus the gas saved over the year.

Still kicking myself for missing that 2016, however I did find a 2014 with 52k miles nearby. Older yes, but looks like it's a little better optioned with ACC possibly. Going to test drive it tomorrow. We had worked out a price of $13,300 out the door (including tax, tag, title, dealer fees) for the 2016, so if I can get the 2014 for less than that I might end up that route. I know about the plastic bolts of the 14-15s, which I'll have to worry about, but we'll see what happens tomorrow. Have to make sure to check the battery on this one too.. Hoping it's not degraded too much either..

 

[alohart]

I know about the plastic bolts of the 14-15s, which I'll have to worry about, but we'll see what happens tomorrow.

The motor mount bracket attachment bolt is steel, but the bracket itself is a plastic composite. A software update reduces stress on this bracket, so there haven't been as many reports of broken brackets or bolts as there were before this updated software was installed. Reports have indicated that the earliest system software version that includes this change is I01-15-11-502 released in November, 2015. If an i3 you're interested in has an earlier system software version, the bolt and bracket are at more risk. BMW would almost certainly charge several hundred dollars to update the system software on an i3 out of warranty.

I don't worry about the bracket or bolt breaking because I avoid putting stress on the motor mount bracket by avoiding flooring the power pedal pulling away from a stop and by trying to prevent a rear wheel from momentarily losing contact with the road (e.g., by not dropping off a curb).

 

[slsrs6]

So just thought I'd give everyone an update.

That 2016 I thought was sold? The people never came and the dealership called me and said it was available again yesterday evening! I had been shopping all weekend and that was by far the absolute best deal in FL. The color I wanted (black) and the interior (light cream). It was also the one I had already test drove and knew the battery was in excellent condition.

So after they called I raced down there and paid for it and did all the paperwork. I had a good test for it though since the dealership was 71 miles from my home.

It was fully charged when I left and said 91 miles on Eco Pro+. I drove 20 miles to a charging station and it had dropped to 65 mile range. I had a friend driving my truck and he stopped to get us some dinner and then met me at the charging station, which was a Chevy dealer. They were real nice and let me charge for free.

We ate and let it charge to 75 miles. So I had 75 miles on Eco Pro+ (It was just slightly over the 3/4 mark on the battery meter). To home was 51 miles left.

I set out and at the first there was a difference of 24 miles between the estimated range and the actual distance to home, but that gradually dropped to 18 and stayed steady for the remaining half of the trip. I finally got home with the battery just below 1/4 left and an 18 mile range.

I was very impressed!! There's a trip computer there that said I was getting about 4.9-5.1kwH/mile.

I'd like to say I could have covered the whole trip in one shot, all 71 miles. I was very impressed! Very happy with the car and looking forward to using it much more!

 

[eNate]

Congrats! Sounds like you've got a healthy battery.

 

[slsrs6]

This is my first EV, so maybe this is basic question.. Can you charge safely while it's raining? If I charge my car outside at night and it rains during the middle of the night, will that be okay? I'm assuming it's protected..?

Also..

I know it's okay to leave plugged in overnight. Can I leave it plugged in over the weekend as well? i.e Friday evening to Monday morning? Or should I unplug it from the charger Saturday morning and let it sit till Monday?

How long can it sit idle? How long can be plugged in for? I'm assuming it trickle charges once the battery reaches full?

 

[eNate]

Rain is fine. The connector is double shrouded in a way that it would take a real sustained direct blast of water to infiltrate. Some owners in colder areas have problems with snow and ice making disconnect difficult.

Leaving it plugged in for days is fine. Charging shuts down once full, and there's no trickle charge capability (or need, really, the traction battery doesn't lose much while parked for a few days; the 12 volt is in constant use by the vehicle electronics while parked).

Aloha Art can give you some tips for long term parking.

 

[slsrs6]

Thanks for the info Nate! That is very helpful. And yes I am finding Art is always the one with all the answers.

 

[alohart]

And yes I am finding Art is always the one with all the answers.

I've participated in this forum since we bought our 2014 BEV in November, 2014. I've learned a lot from those before me and try to pass it forward. I was a pioneer buying a 2000 Honda Insight, the first hybrid sold in the U.S., a 2012 Mitsubishi i-MiEV, our first EV, and an i3, so I understand the challenges that a pioneer can face. Sharing information among other early adopters can make the difference between being really frustrated and being satisfied applying solutions that others have shared. I don't claim to have all the answers, but I do have some strong opinions

The i3 Owner's Manual claims that an i3 can be stored for up to 3 months while plugged into an EVSE. It recommends asking a BMW dealer about storing an i3 for longer than 3 months.

The problem with storing is the 12 V battery discharging so much that starting an i3 isn't possible and that an extremely discharged 12 V battery can be permanently damaged. The high-voltage battery pack is electrically disconnected from the high-voltage circuit when an i3 is off, not being actively charged, not being preconditioned, and not having its doors, frunk, or hatch unlocked or opened. The self-discharge rate of a Li-ion battery cell is very low, so the battery pack won't self-discharge much more than 1% per month at a charge level of ~50%.

During the 4 periods in which we stored our i3 for periods of 3 to 9 months, our BMW dealer recommended disconnecting the negative cable of the 12 V battery as would be done with any ICE vehicle, charging the 12 V battery to full with a battery charger, leaving the battery pack's charge level at 40% - 60%, and not leaving an EVSE plugged in. The self-discharge rate of an i3's absorbent glass mat (AGM) 12 V battery is also very low, so it could safely be stored without being on a trickle charger for a year. Following our dealer's recommendations, we have had no problems putting our i3 back on the road after being stored. Its 12 V battery is still the original although I bought a replacement that's ready when needed.

I don't understand why the Owner's Manual recommends leaving an EVSE plugged in for up to 3 months. After the battery pack is full, its charge level might not drop enough over 3 months for charging to resume, and it's certainly not critical to keep the battery pack fully charged. In fact, leaving a Li-ion battery cell at a high charge level for an extended period increases its degradation rate, especially in warm conditions. There's almost no evidence that the 12 V battery would be kept charged by leaving an EVSE plugged in. In fact, there's more evidence that the 12 V battery won't be maintained as a result of several reports of dead 12 V batteries even though an EVSE had been plugged in. I don't leave our EVSE plugged in when charging has completed and have installed an on-off switch on our EVSE circuit to power off our EVSE when not charging. We have more than the average frequency of power outages and surges, so I try to protect our EVSE and our i3 from these electrical problems.

I wish that BMW had documented more about how an i3 operates. In many cases, we are left to guess or try to deduce based on observations. We are almost certain wrong in some cases.