Running the Battery to 0%

[ytwytw]

This truck behaves nothing like the Tesla at low SOC. Please don’t mislead people in that manner.

I’ve run my Teslas down at 0%/0 miles remaining and I have never in 8+ years of owning Teslas, run out and come to a stop on a Tesla. That includes running it down with 10% degradation on a 200,000mi+ Tesla just recently. A Rivian, I can confirm behaves just like a Tesla does at low SOC but a Lightning does NOT.

The best way to describe this truck at low SOC is that it is inconsistent. I run mine regularly down below 5% - or I used to until I ran out on two occasions. Like Kyle, the only EV I’ve owned that has left me stranded, unintentionally due to use

The best possible explanation given is that maybe the BMS calibration gets out of sync over time, but that in itself is a bit concerning. This truck simply can’t be trusted on a regular basis at low SOC, and I don’t have an explanation as to why and neither does Ford at this time.

My advice is to avoid running her below 5% if you don’t absolutely need to.

Kyle trusted too much on BMS, but power output never lie

I have seen enough people stranded their Tesla on the road simply trusting 8mi left or 1% but suddenly dead before hitting 0%

weak cell or sudden drop of voltage can kick in Low voltage protection instantly regardless soc or capacity left

the only fix for Tesla is recalibrate the BMS/battery to make sure it reports the correct data

this is no difference for F150 Lightning as well. When the battery is low, power limit kicks in and you can pretty much ignore SOC reading.
if you have driving model s/x before refresh, similar dot lines showing power output limit and when it hits the bottom, the car dies regardless the soc is

Sure, the UI display different way, but the idea is the same.

I hope FDRS or Forscan can have a feature to recalibrate BMS, that would help lots
Recent Tesla service mode is able to drain the pack and recharge to 100% to calibrate, that is also helpful to keep data accurate (not necessary make the battery healthy lol)

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[Newton]

This is one area that really needs improvement across the board. Fortunately most people don't let it get that low, but in addition to what you said, the fundamental problem is that batteries do not act like our mental model says that they should.

The BMS counts the amperage going into the battery, and the amperage going out of the battery. That is fairly easy to do but it does not tell you everything that you need to know and it gets out of sync very easily. I have a state of the art BMS for a house bank on a boat, and if I do long cruises without stops at land for a few weeks the poor thing becomes nearly useless. I look at battery voltage just like the old timers.

We are presented the data as if the is were a gas tank. I put in 50 gallons, I use 45 gallons, so I have 5 gallons left. That is not really how batteries work. If you put 50 kWh into the battery in the summer you will get more range than if you put 50 kWh into the battery in the winter. Pulling 10 kWh out of a battery that is nearly fully charged lowers the state of charge less than pulling 10 kWh out of a battery that is nearly dead. Discharging a battery at a high rate gives you less total power than discharging it at a lower rate. There are complex physical processes going on that vary a great deal across vehicles - but the software engineer's job is to "make it look like a gas tank."

I'm not sure what the ideal thing is, but more information from the truck would be really helpful. If the state of charge is low, show a voltage graph so you can see how rapidly the voltage is falling to the cut off point. Make the state of charge and voltage more prominent, and perhaps show error bars around it assuming that it is possible to determine how much drift has happened with lithium batteries. Show error bars around the range, and perhaps even show the range relative to miles/kWh so you know that you have X miles at worse miles/kWh than you are now doing, Y miles at the current miles/kWh, and Z miles at some realistic more efficient speed.

 

[RickLightning]

That would be an interesting thing to try. We'd need some adapter to plug any 240V home charging cable into the 240V outlet in the lightning though (that's a plus on the Cybertruck, which gets a NEMA 14-50 plug in the bed).

Nothing to test. Been done. I did it also. Use your Ford Mobile Charger, or make sure the other vehicle can dial down to 30amps with theirs. 32 will pop the outlet breaker. Ours is 30amps.

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[mrau]

My 2023 Lariat also came with an adapter. It has a Ford part number on it. But as others have stated there are other styles of adapters that will work.

On the label it states to set EV charging limit to 24 amps (output) when using adapter.

 

[Adventureboy]

When planning a flight we plan for our destination and an alternative should the destination be untenable.... I've simply transferred that method to driving EVs. I plan to stop a bit earlier with a known backup plan that I can still reach. It's happened twice in 20 months where my chargers at my planned charge location were inoperable. Backup plans worked. Tesla Superchargers will make it much easier to plan for backup.
I try pretty hard to keep it above 20%. My panic line is 10%. I've only hit high single digits a few times. Haven't run out - don't plan to

 

[jefrank]

By September of 2022 I don't think these were added to the vehicles. I didn't have one in mine.

Didn't get one with my August 2022 delivery, either

 

[Danface]

What day is it again?

It's Groundhog Day! (They say our love won't pay the rent ... )

 

[Pioneer74]

I love how Ford gave you an adaptor you can't use with their mobile charger.

 

[Zprime29]

Buy this - https://amzn.to/4cGLZ3N

I bought that one, they sent me the wrong adapter. I returned it as wrong item and wanted a replacement. They sent me the same incorrect adaptor again. I stopped trying to order from them. Maybe it was just bad luck, but I have a bad impression of them now. Box was labeled correctly, someone just put the wrong item in it or the wrong label on the box....twice....and I got both of them....yeah.....

 

[maineiah]

I've done it. I can tell you this. 0% means 0%. There's maybe a 2 mile buffer. In a cold snowstorm in Maine, I landed in my garage with the front axle inside and the rear outside, truck DEAD. My Level 2 charging cable was just long enough and it starting charging 10 minutes after plugging in.

How I got into that position? Don't judge, I'm just telling my story. It was fatigue. We were coming come from Montreal, and had to take a HUGE detour around the White Mountains during a snow storm. My last charging stop left me with the exact charge to get home. I saw the charge diminsish ahead of schedule, but in my mind, I was sure that there would be a buffer (did I mis-remember Kyle's F150 episode?). As I climbed the last hill before home, the truck died at the top, 2 miles from home. 0%, no power. I shifted into reverse, and back to forward, and the truck sort of snapped back to life. We white knuckled it down the slight grade to the house for the last 2 miles. As we approaced the garage with 100 yards to go, I realized I was coasting with no power at all. I clicked the garage door opener when within range, and glided 1/2 way in. The truck had some dash lights on, but that was it.

It was a brutal trip, and I've been an EV'er for some time. It was just odd that in my mind, as I was so tired, that I felt I could just will us home. In a way, I did.

 

[Yellow Buddy]

Kyle trusted too much on BMS, but power output never lie

I have seen enough people stranded their Tesla on the road simply trusting 8mi left or 1% but suddenly dead before hitting 0%

weak cell or sudden drop of voltage can kick in Low voltage protection instantly regardless soc or capacity left

the only fix for Tesla is recalibrate the BMS/battery to make sure it reports the correct data

this is no difference for F150 Lightning as well. When the battery is low, power limit kicks in and you can pretty much ignore SOC reading.
if you have driving model s/x before refresh, similar dot lines showing power output limit and when it hits the bottom, the car dies regardless the soc is

Sure, the UI display different way, but the idea is the same.

I hope FDRS or Forscan can have a feature to recalibrate BMS, that would help lots
Recent Tesla service mode is able to drain the pack and recharge to 100% to calibrate, that is also helpful to keep data accurate (not necessary make the battery healthy lol)

Report back when you actually experience it vs just what you read please. Again, don’t mislead people.

Teslas drop off and ramp off is significantly different from the Ford. It’s not as sudden.

The reduction in the Tesla is equivalent to a 30-40% power cap on the Lightning, and remains driveable so you can get to a safe location. The Lightning reduces your power down to less than 5%. That’s not drivable.

I have personally experienced power reductions on both, the Lightning at 95%, 50%, 35% and less than 5%.

 

[Newton]

At what state of charge does it become undriveable? I saw power reduction to about 95% somewhere around 15% SOC but it had no effect on performance. Based on this discussion I don't plan on going much lower, but I have taken my EV6 down to 4% with no ill effect.

 

[Box Cat]

Drove my truck down to 2% as an experiment and did not observe a power reduction, although I was going around the neighborhood at only 25/35 mph so that I could reach home before approaching 0%.

 

[edcoble]

Recommendation: Don't do it. Most people never do. But with our charging infrastructure the way it is, it's entirely conceivable that you could be on a trip, run across dead chargers, and then run out of juice before you can reach the next nearest one. MotorTrend runs every long-term EV completely out of juice once to report on what happens. In our case, it was not terribly pretty. I'd be eager to hear if anyone else has ever tried to charge a completely dead Lightning battery from a Level 3 charger (b/c, spoiler alert: it didn't work at the EVGo one we tried).

https://www.motortrend.com/reviews/2023-ford-f-150-lightning-xlt-yearlong-review-update-8/

My experience: in January, driving from Trinidad CO to Amarillo TX 230 miles or so, we found ourselves in an unexpected snowstorm with cross-winds and 30 degree temperatures (NOT forecasted). Would have been able to make it normally driving 60mph given the substantial drop in elevation.

Slushy snow built up on the underside of the truck adding quite a bit of weight to our load (two adults, two border collies, suitcases, etc). There were no high-speed chargers till Amarillo. Kept reducing speed as I watched the battery efficiency plummet. Pulled into the Walmart parking lot where EA chargers were located showing 0%age--and the truck stops, maybe 50 yards from the charger. I told me wife to come around to the driver's side and I'd push it to the chargers. ....BUT I thought why not try starting it any way--and the truck started and I made it the 50 yards to the charger.

We had no problem charging it to 80% and drove on to Lubbock for the night (no more snow, warmer temperatures).

 

[MickeyAO]

Based on what I've seen in testing this cell, I'm going to make sure I do not go below 20% of actual SOC

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