used i3 which have not been driven (or charged) for a long time?

hello I find you forum very interesting and thru to BMW forums.
I have been shopping for a few months now and noticed that in Quebec the used i3 are sitting in the dealer parking lot for a long time before they get sold (more than 4 months). note that -40 in winter will occur a few times...
So far I tried 2 i3's both with REX. from different dealers, one BMW (a 2016) and one (a Ford dealer selling a 2014).
Believe it or not both were at zero capacity, the one from the Ford dealer immediately kicked the REX and after about 1/4 mile kicked in a real limp mode with check engine on... what a turn off for my wife! :-( I told her that an i3 is as much "alive" than any ICE vehicle. this exercise was a real turn off...
The other one from BMW had a similar issue if not worse, even the "small" battery was not strong enough to start the small motor!
so again a turn off...

I am confident that the i3 in normal mode is fun to drive... as much as my 328xi is or my Z3 was...

Which bring me to my real question: if an i3 have been sitting on the parking lot for 3 months without proper care... did they harm the battery (or the car doing so?

On the very same subject, we heard that a Telsla with a dead battery is almost scrap due to battery cost, we know Telsla use a different battery than BMW... Last week I test drove a new Leaf and the salesman said the if the car run off of juice 5 times the battery warranty is voided... is there any similar particularities I should know?

Thank you

BMW's manual says to have the battery charged if it's not going to be used for awhile. That's probably true for the 12vdc battery, too. That 12vdc battery gets charged when you're charging the main battery and when the car is running. At the minimum, it's powering the alarm system and the clock circuits plus the cellular module when the car is 'off', so there is some load on it. It must have enough power to energize the computers, which run off of it for the car to operate. BMW's battery management doesn't allow the main battery to be used down to zero...it will report zero when there's still some charge in it. They do this to help ensure its longevity (8-years, it must hold at least 70% of a new one). Some of the other brands do actually let the battery be fully discharged, which will hurt the life of the thing.

My guess is that the 12vdc battery is dead and will need to be replaced, but the main battery pack is probably okay.

There's a service menu that can report the main battery's capacity, but the 12vdc battery must be okay to run the computer to access it.

Thank you for your quick reply, my greatest concern is the *main* battery, if it was not charged for many weeks could this harm it?
or even depreciate the 8 years warranty (i.e. that BMW could prove that previous owner neglected the car, the lack of charging it may look like neglecting to them)

The 12vdc battery, if discharged then exposed to cold temperatures could be damaged. A discharged lead-acid, even an AGM one, can split or distort the case by freezing when discharged. I'm not positive on the main battery pack, but BMW does say to have it charged before letting it sit for a long time. Without accessing the service menu and checking, you wouldn't know for sure.

bmwtourer said:

Thank you for your quick reply, my greatest concern is the *main* battery, if it was not charged for many weeks could this harm it?
or even depreciate the 8 years warranty (i.e. that BMW could prove that previous owner neglected the car, the lack of charging it may look like neglecting to them)

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The Li-ion battery pack should not be allowed to remain at a very low charge level for extended periods. If I park our BEV with a low charge level, I will eventually receive an email message from BMW asking me to charge the battery pack. I believe there's also a "charge me" message displayed on the instrument panel when shutting down the car when its charge level is low. I don't know what displayed charge level is considered "low". I'm guessing around 10% which, when considering the ~10% inaccessible low charge level capacity, is probably an actual 20%.

The Li-ion battery pack has a very low self-discharge rate (I've experienced ~1%/month over a 6-month storage period), and when an i3 is off and not charging, power from the Li-ion battery pack isn't being used (the only vampire loads are 12 V - burglar alarm, keyless entry system, clock, etc.). If the 12 V battery is bad or has been allowed to discharge, when a door is opened, the Li-ion battery pack is connected to the 12 V battery to charge it, so if this is done many times without charging the Li-ion battery pack, the battery pack's charge level could eventually drop to an indicated 0%, I suppose.

I don't know whether BMW keeps track of the treatment of the Li-ion battery pack, but that information would certainly be available to BMW. I haven't read anything in the battery pack's warranty that would void the warranty if the battery pack is allowed to stay at a low charge level for an extended period.

Unless there aren't other good used i3 choices available, I would probably avoid those whose battery pack has been allowed to remain at a low charge level. A bad 12 V battery could be replaced for a reasonable cost.

I was told at one of the dealerships that they don't have enough chargers to keep the i3's charged up so you can only test drive them on gas! Pathetic. As a dealership that sells electric vehicles of their own brand, they need to figure it out. Even it's just Level 1 charging, they gotta do it. Pretty sad that the dealership couldn't even take care of their own cars.

Worst case, it takes about 4-5 hours to recharge an i3 from nearly depleted, and most of them aren't, or shouldn't be that low. That should let them cycle at least a couple onto an EVSE a day, and if not being driven, they'd hold that charge for months. IMHO, they do not have an excuse. Driving an i3 REx on gas with a nearly discharged battery will turn many prospective drivers off. Doing that with a BEV would risk them being stranded, which again, would be a turn-off to many.

Some dealerships embrace the EVs, and understand...they also tend to sell more of them. FWIW, having the infrastructure to include a CCS (DC fast charging) station is a bit more expensive, and while that would definitely speed up the process, the cost is a lot more. One of those takes a fairly significant power input, and not counting the cost of the unit, and not everyone's electrical service can support one.