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Never been this low on the charge before and saw a message or two on the cluster display that I had never seen before either. :)

I knew that I was 17 miles and 20% from my destination when my gauges showed that I had about 22% and 20 miles left. Could have stopped at the last charging station on my way home at that point, but I figured that I could probably make it, plus I half wanted to see what happened when I ran out of charge. Kind of glad that didn't happen though.

BTW I charged up for an hour at a BMW dealer to make sure I got that far.

Len
2014 EV Coupe 12,750 miles
2014 EV Cabriolet 2,150 miles
 

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2014 Cabriolet bought in Sept 2016 with 6,470 mi
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You can go lower

I've hit 0 a few times and around 1 over a half a dozen, but I've never had it shut down on me as of yet after over a year and almost 4K miles.

It helps to have less than a 4 mile trip to and from work for this sort of thing.

I'm curious to hear from someone who has had it shut down.
 

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Brave !

I read in the Smart user manual that even after shutdown you can toggle the Start position of the key and still bump the motor enough to move the car "a few meters". I wonder exactly how far that really goes !
 

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On my first trip with mine yesterday I managed to take it down to about 3 or 4% while trying to find a level 2 charger on my way home from dealership.


Sent from my iPhone using Tapatalk
 

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Oh, believe me, it CAN and WILL die. Funny story.

I had an eager and anxious salesperson on his first day end up with a curious customer a few years ago. The "new" (at the time) 2013 smart EV was just released, much improved over the "TEAM 250" smart EV. Improved range, much improved acceleration performance, and improved reliability.

In any case, this particular day we were dealing with more showroom traffic than we could handle for the new release as we could barely get the vehicles off the delivery truck, to service for pre-delivery inspection, then to the sales area for charging and eventual test drives/sale.

New sales guy gets an interested showroom guest. He grabs a car without asking anybody for help, first day on the job and didn't previously have much more than a discussion about what the new smart EV was all about. In his mind, "it's just a car, can't be that complicated" so he doesn't get anybody. He grabs the car, takes his client, and he's gone.

A few miles later he's calling for help. The car stalled with a dead battery because his rookie self took a car with a battery charge of literally like 1%. I get the car towed back to the dealer but I'm letting him have it in my office about first of all, who asked him to go get the car and take it off the lot on his first day, second of all why did he assume he knew what the state of charge was, third of all how inconvenient to the customer who now had to wait on the side of the road with you for help, fourth of all how I need to pay a tow truck to get the car, fifth of all now we have a car without license plates on side of the road, etc, etc, etc,.

It all worked out in the end. I believe the client ended up laughing it off and buying the car a day or two later anyway.

The new salesperson learned that the 0 to 100% driving efficiency score and 0 to 100% SOC gauge, are different sets of information.
 

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Just because you CAN take the state of charge that low doesn't mean you SHOULD take it that low. It has been fairly well determined that you are shortening the life of the battery, so you will pay for it in years to come (assuming you still have the car). Of course, you could just sell it to an unsuspecting buyer.

There is a good reason SMART recommends you keep the battery between 20 and 80% state of charge at all times. Going outside that once in a rare while will not cause a significant dropoff in battery life, but continually doing so is not wise.
 

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2014 Cabriolet bought in Sept 2016 with 6,470 mi
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Only time will tell

Every Li-ion battery pack I have ever had has been treated the same way - charge it up, use it until it runs out of power (or as close as I can get), then charge it back up again.

All my devices - phone, laptop, power tools, shavers batteries seem to last longer then the people I know who charge them up before it runs out.

I will likely be keeping my 2014 Cabriolet that I got last year with 6,470 miles on it until the battery pack gives up the ghost.

In the meantime, I keep track of everything I can for each trip and each charge and will be happy to share the results good, bad or indifferent.
 

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I keep my log in an app called ‘my ev app’, gives me realistic efficiency and distance I can go for each battery %.
 

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Hmmmm...

Just because you CAN take the state of charge that low doesn't mean you SHOULD take it that low. It has been fairly well determined that you are shortening the life of the battery, so you will pay for it in years to come (assuming you still have the car). Of course, you could just sell it to an unsuspecting buyer.

There is a good reason SMART recommends you keep the battery between 20 and 80% state of charge at all times. Going outside that once in a rare while will not cause a significant dropoff in battery life, but continually doing so is not wise.
I cannot seem to find where it is written down about keeping the battery between 20% and 80%? Also I cannot find where it is documented that going below 20% and above 80% should be done only rarely. All the text I read in the owners manual suggests charging up to 100% and only says you will get a message when below 20% (Reserve Notice). I know you also will get a "Low Battery" notice below 5%. Did I miss something?
Cheers,
Mike
 

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Relax and enjoy your electric car.


Everything known about the 20-80, discharge to charge rate recommendation, has been
exquisitely built into the "Battery Management System", that rides on
top of your High voltage battery pack.
The 100% charge you see on your dash that you think you are playing with is Artificial.
That stated 100% is really a state of charge that is fit in carefully between 20% buffers, top and bottom.


The 100% you so carefully manage is being more carefully managed by the BMS, than you could ever imagine.


Drive it like you stole it !

You can not abuse your HV Battery Pack,,,,, even if you try!
 

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Just because you CAN take the state of charge that low doesn't mean you SHOULD take it that low. It has been fairly well determined that you are shortening the life of the battery, so you will pay for it in years to come (assuming you still have the car). Of course, you could just sell it to an unsuspecting buyer.

There is a good reason SMART recommends you keep the battery between 20 and 80% state of charge at all times. Going outside that once in a rare while will not cause a significant dropoff in battery life, but continually doing so is not wise.
Good point.

And if the pack is brought down to near zero indicated SOC, it is important to get it plugged in and charging promptly - especially in cold temperatures. The one time that I took my smart down to a couple percent at a temperature around the freezing mark, the panel indicated "charge immediately" and a continuous beeping alarm sounded, both continuing even after removing the key and closing the doors (no, I didn't leave any lights on) The alarm only stopped upon plugging in to the charging station.

Optimist's advice is not correct. There are things you can do to a Smart or probably any EV that could ruin the battery pack. The owners manual describes some of these things. This is not a shortcoming of EVs - there are far more things one can do to ruin an IC engine or its transmission than ruin an EV battery/drive system.
 

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Every Li-ion battery pack I have ever had has been treated the same way - charge it up, use it until it runs out of power (or as close as I can get), then charge it back up again.

All my devices - phone, laptop, power tools, shavers batteries seem to last longer then the people I know who charge them up before it runs out.
Except that you are not actually running the battery all the way down. The device has a battery management unit that shuts the power off well before 100 percent discharge. In the case of small devices, which use LiCoO2 chemistry, this is very critical - as recharge such a battery if discharged below a certain point will result in a runaway thermal reaction that can start randomly, resulting in the device bursting in very hot fire that has burned houses down and brought cargo airliners down.

It is well-established that the cycle-life of a lithium battery goes down with depth of cycle. The cycle-life/numbers of charge cycles being optimized by charging the battery at about 40-50% DOD. Many devices are set up to manage the batter this way.
 
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