5% battery, 10kwh

[Firn]

For those that have run your battery down (and logged it) what was your energy remaining?

.

In 20,000 miles i have not yet ran the battery down below 18% or so and seeing posts of the battery going flat suddenly when below 10% concerned me.
I finally had a chance to run it down low, making it down to 5%. While logging the claimed capacity was around 10kwh but I wonder for those that have had theirs go flat suddenly, what did yours look like.
Fwiw, the soc drop below 10% didn't change at all.

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[davehu]

after a 35mph white knuckle drive 20 miles down the freeway this is my situation when I got the Tesla SC . (white knuckle because I was so close to not making it.)

 

[SpaceEVDriver]

I haven’t logged it, but I have run it down to 1% and 4%.
Besides the power limiting, nothing unusual happened. I’d heard about these concerns as well, so I have only run down when I was near enough to home that I could walk home and bring my auxiliary battery to the truck to recharge it if it failed. Never needed to do that.

 

[RickLightning]

For those that have run your battery down (and logged it) what was your energy remaining?

.

In 20,000 miles i have not yet ran the battery down below 18% or so and seeing posts of the battery going flat suddenly when below 10% concerned me.
I finally had a chance to run it down low, making it down to 5%. While logging the claimed capacity was around 10kwh but I wonder for those that have had theirs go flat suddenly, what did yours look like.
Fwiw, the soc drop below 10% didn't change at all.

So you had 10kWh showing as Energy, at 5% displayed SOC?

What does your last sentence mean?

At 7% SOC, I had 11.04kWh.

The reason that math doesn't work (i.e. 11.04 / .07 = 157.7kWh) is because there is uncertainty at the top and bottom of the pack due to accumulated errors over time (per Lee on the Mach-E forum). If you charge to 100% and let the cells balance, and battery is at 77 degrees, then the numbers get more accurate.

I use the Energy number to know if I can make it to a destination, i.e. 11.04 x 1.8 = 19.9 miles. I would feel safe driving 15 to 16 more miles.

 

[Kansan]

My 24 Flash ran perfectly over the entire battery range from 100% - 0% indicated.

At 0% on the dash Car Scanner shows 0.5% displayed and 3.97% actual with 4.64 kWh remaining in the pack. This was after letting it sit for a few hours (intentionally let it rest before recharging for BECM calibration).

 

[Yellow Buddy]

For those that have run your battery down (and logged it) what was your energy remaining?

.

In 20,000 miles i have not yet ran the battery down below 18% or so and seeing posts of the battery going flat suddenly when below 10% concerned me.
I finally had a chance to run it down low, making it down to 5%. While logging the claimed capacity was around 10kwh but I wonder for those that have had theirs go flat suddenly, what did yours look like.
Fwiw, the soc drop below 10% didn't change at all.

Mine was at 0% with 0miles and 0kWh remaining….but something tells me that doesn’t help answer your question.

 

[FloridaMan655321]

In 20,000 miles i have not yet ran the battery down below 18% or so and seeing posts of the battery going flat suddenly when below 10% concerned me.

From my (probably bad) memory, the issue with people going flat when under 10% was from DC fast charging on a long trip. Internally there was something messed up and the calculation or what it showed you was incorrect. So if you're charging at home, there isn't an issue with going under 10%. But if you travel and are on your 4th or 5th DC fast charge, you probably don't want to go below 10%.

 

[Firn]

So you had 10kWh showing as Energy, at 5% displayed SOC?

What does your last sentence mean?

At 7% SOC, I had 11.04kWh.

The reason that math doesn't work (i.e. 11.04 / .07 = 157.7kWh) is because there is uncertainty at the top and bottom of the pack due to accumulated errors over time (per Lee on the Mach-E forum). If you charge to 100% and let the cells balance, and battery is at 77 degrees, then the numbers get more accurate.

I use the Energy number to know if I can make it to a destination, i.e. 11.04 x 1.8 = 19.9 miles. I would feel safe driving 15 to 16 more miles.

Yes

Simply that I did not experiance any unusual behavior below 10%.

Calibration is part of the reason for doing this. After driving it down I charged to 100% since I was driving a bit more the next day. Unfortunately I was unable to let it rest between finishing the drive and starting the charge to 100%.

In general I would have felt comfortable driving more miles as well.

 

[Zprime29]

Comes out to around 1.24kWh per 1%.
When I charged back to 100%, I think it was around 128kWh.
Close enough that I'll call it good for 40k miles.

 

[biers]

I’ve run mine down to less than 5% at least a dozen times. Rolled into the driveway twice at 1%.

Only once have I ever had a problem. I was at 3% getting off the freeway. Probably mile mark 400 on the day (2 DC sessions prior) and it dropped to 0%. Turned the truck off for a few minutes and was able to limp the quarter mile to the super charger.

I have a SR battery.

 

[abcut973]

I have run down my SOC to 3% display. But carscanner would show 5%. I've noticed below 50% that is generally the case. The truck wants you to think you have less power than the HVB actually has. So no issue with driving it below 10%. At least that is my experience so far.

 

[MaintGrl]

I think the lowest I have had mine was 15%. As far as calibration, for the last year I have been charging from a 40 or 50% charge to 90%. When I started the GOM was in the 210m range (I have a SR Battery), but the GOM over time has dropped to about 195m. So recently when I charged, I went to 100%, which got me to 228m. Next time I charged to 90% I was back up to the 210m range. Battery balancing....

 

[grange]

Not by choice. Charger was out out of service 20 miles before destination. It was about 10 degrees out ..pucker Factor the balance of the way.

 

[MidAtlanticLightningClub]

 

[Firn]

I think the lowest I have had mine was 15%. As far as calibration, for the last year I have been charging from a 40 or 50% charge to 90%. When I started the GOM was in the 210m range (I have a SR Battery), but the GOM over time has dropped to about 195m. So recently when I charged, I went to 100%, which got me to 228m. Next time I charged to 90% I was back up to the 210m range. Battery balancing....

Thats crazy, my GOM is so far from reality its sad. Yours looks reasonably accurate

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