Got to 2%, 5 miles to go - then I experienced something I didnt

[Rocket808]

what is your charging pattern if you don’t mind me asking ? I know that if you do a lot of DC fast charging i.e. on a long road trip the BCM can get out of whack and the percentages be off a little bit…( such as what happened to the out of spec guys on the EA race) … not sure if it also happens for those who do not charge often… I noticed my percentage hopping up and down after mine sitting for a few days…. I usually don’t plug in till I’m about below 50% ? And I wonder if level two charging to a high state of charge balance is the cells…. And helps recalibrate the bcm?

I personally charge nearly solely on AC using FCSP to 80% daily “ABC”. I did DCFC in the beginning of getting the truck awaiting my system to be installed.
So typically DCFC is limited to road tripping - probably charged to 80% 10 times in the past 18 months on EA and now Tesla.

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[gbuydos]

The one thing i did like about my Toyota RAV4 EV was it had turtle mode. Basically at bottom of the SOC it went into turtle mode, this allowed you up to about 20 mph for a few miles to limp the vehicle home or a charging station. With a max 108 mile range, i used it a few times.

 

[fhodgdon3]

This winter I was driving home and my battery got down to 3%, at a stop sign 200' from my driveway the truck shut down, wouldn't budge. I sat there thinking how many feet of extension cord I had (for maybe 60 seconds) then I tried again to start it, luckily it "limped" into my driveway. Won't let that happen again. Certainly have to be way more vigilant here in New England during the winter. It dropped from 10% to 3% really fast at around 15 degrees out.

 

[hajalie24]

This winter I was driving home and my battery got down to 3%, at a stop sign 200' from my driveway the truck shut down, wouldn't budge. I sat there thinking how many feet of extension cord I had (for maybe 60 seconds) then I tried again to start it, luckily it "limped" into my driveway. Won't let that happen again. Certainly have to be way more vigilant here in New England during the winter. It dropped from 10% to 3% really fast at around 15 degrees out.

You know, on my most recent road trip the weather got cold and the estimated percentage for when I got home kept dropping.. At first Google said we would get there with 15% range but it got down to 7% and would have kept going down. My wife got worried so we stopped to charge at a slowish DC charger, added 14%, got home with 16%, so we would have gotten home with 2% and I thought that would have been perfect and we didn't need to charge.. Well now I'm glad we did, especially since it may have limped on while still on the highway...

Next time Google Maps suggests charging cause we'll arrive below 10%, I'm going to do it.

 

[Rocket808]

You know, on my most recent road trip the weather got cold and the estimated percentage for when I got home kept dropping.. At first Google said we would get there with 15% range but it got down to 7% and would have kept going down. My wife got worried so we stopped to charge at a slowish DC charger, added 14%, got home with 16%, so we would have gotten home with 2% and I thought that would have been perfect and we didn't need to charge.. Well now I'm glad we did, especially since it may have limped on while still on the highway...

Next time Google Maps suggests charging cause we'll arrive below 10%, I'm going to do it.

I agree. I will not push it thinking “it’s greater than zero %.”
It sucks to stop, but even 5 min at a Tesla supercharger pulling 172kW gives some buffer.

 

[Firn]

I have wanted to push mine down into the low single digits, just to help calibrate the BMS, but have been afraid to do so. With the reports of SOC suddenly plummeting below 10% i could be local and still not be able to get home, or to a charger

 

[Peddyr]

I did begin to freak out a bit having the “I can’t believe I just ran outta battery” feeling

Who could have anticipated that?

 

[George D]

Obviously, she's a keeper!

I guess so. I mean, we've been married 48 years. So we have that going for us.

 

[edcoble]

IIRC others have mentioned that turning the vehicle completely off for x minutes allowed a certain amount of recovery that let them go again.

That happened to me. Showing 2% when the truck stopped. I had it towed half a mile home--BUT then was able to start it and back the car into the driveway to begin charging.

Irritating to say the least.

 

[edcoble]

IIRC others have mentioned that turning the vehicle completely off for x minutes allowed a certain amount of recovery that let them go again.

Yep. That worked for me. After a few minutes of feeling chagrined.

 

[richl025]

TLDR: as stated in other threads - 0% is 0 power left. But the power for propulsion actually drops to zero before that from around 2%. It appears to cycle down and up.
Recommendation: don’t push it below 10 miles of range remaining according to GOM.
——-

I knew as my SOC reduced, the max power decreases from 100

I did a local trip last night, basically picking a relative off from airport and dropping them off and heading home, I decided to try to get home with approximately 1 mile range - so I did a very small amount extra driving to be as close as possible.

I pulled up to a stoplight at 2% charge, and when it turned green, I had zero throttle response. Available Power on the dial showed 3 (maybe lower?) but no reaction from the truck. I had cars behind me so hit the throttle a few times. They went around. I snapped a photo at 3% power, yet with 2% charge (and 5 miles).

I was on a flat road and it was nearly all downhill (very slight grade) to go from my location - was about a mile away from my house.

I did begin to freak out a bit having the “I can’t believe I just ran outta battery” feeling - no difference in running out of gas feeling. All the inside electrical was still 100% normal and turned on my hazards.

I power cycled the car, though I don’t know if that did anything.

I watched the power bar cycle back up to 38% and the light cycled back to green again and I was able to continue on. I became extremely cautious now as I had an instance of no power at all.

got home with 1 mile range! I don’t need to do this experiment again.

The ICE cars gurgle and spit when they are at their last drops of gas. Our EVs just stay silent!

I ran my Lightning down to zero when I first had it - I was trusting the GOM and had to climb a mountain pass to get home.

Bonehead rookie mistake.

My SOC read 0% for about the last 1/2 mile up to my house (and my L2 charger). Man, I was sweating bullets! I was too nervous to think to take a photo, though...

 

[chl]

A cautionary tale.
I learned to Plan ahead and know my E-vehicle's rate of energy use per mile under a given set of circumstances after getting my first EV, a 2012 Nissan Leaf in Dec 2011.
The Leaf has a so-called "Turtle Mode" which kicks in when the SOC gets too low - it conserves battery energy my limiting the speed, acceleration, heating and AC off, etc. I never experienced it, thank goodness.
Supposedly it happens when the SOC is low, and / or the temp is so coooold that the battery goes into a cold protection state.

I always limit the discharge level to no more than 50% from where ever it started, so if at 80% I don't go below 30%, for battery health/lifespan reasons. I can do that with the Lightning easily. With the Leaf, a 24wHr battery and 4.7mi/kWh but 13 years old so only about 80-85% capacity, it means a limited range of about (16.32 - 6.12) kWh x 4.7mi/kWh = 48 miles, good enough for local trips to the store etc..

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