Need for Level 1 Charging?

[spamgoeshere2]

I'm traveling a lot now and leave my X at the airport long term parking for nearly a week at a time. With the weather getting colder in the mid-Atlantic I'm wondering if I'm going to need to plug into level 1 power for times when the temps go well below freezing. My understanding is the car will run the heater to prevent damage to the battery.

I wrote to the authority at BWI airport in Maryland and they wrote back about the new level 2 and 3 charging they've added recently. I wrote back explaining in more detail how that is not what I was referring to and explained again how EVs need power in long term parking lots. No response.

It looks like it is only the fancy charging that gets the attention of the people in charge. They don't really understand the charging requirements. Has anyone seen an effort to provide level 1 charging anywhere EVs are parked long term? Certainly it would not be practical to use level 2 charging for this requirement. This airport is charging for all the current charging facilities, so I expect they would want to charge for level 1 charging in the long term lots as well. At $3 a day electricity costs for the few days the cars would actually need to charge, it seems this could be nearly ignored. Not charging for the electricity costs also means you don't need to separate the parking spaces with a gate and separate billing machines.

It seems a lot of their thinking revolves around getting subsidies for the installations as well.

 

[Xelloss99]

Ask if they have parking stalls with "block heater outlets" for diesel trucks in cold temperatures. Those would be outlets powered 24/7 rather than standard block heater outlets that would be either cycled based on time or temperature.

 

[Rocky_H]

With the weather getting colder in the mid-Atlantic I'm wondering if I'm going to need to plug into level 1 power for times when the temps go well below freezing. My understanding is the car will run the heater to prevent damage to the battery.

Read the section in the manual for battery care. The place that the warning comes in says to not let the car sit unplugged below -30 degrees Fahrenheit for more than 24 hours at a time. It's really rare for the Mid-Atlantic region to have Winter temperatures that low.

 

[RTPEV]

Fast Park & Relax at RDU Airport has an "EV section" which basically consists of several 120V outlets. But that works out just great.

The official airport parking deck also has some randomly scattered 120V outlets, although Plugshare reports indicate that staff will unplug EVs that are plugged into them. Unfortunately I really doubt that airport personnel really get the whole EV thing yet.

 

[Sophias_dad]

Don't worry about it. Don't park at the airport with less than 30% charge(and the more the better). Turn Sentry off if you don't mind, although it'll turn itself off at 20% remaining charge anyway.

 

[spamgoeshere2]

Read the section in the manual for battery care. The place that the warning comes in says to not let the car sit unplugged below -30 degrees Fahrenheit for more than 24 hours at a time. It's really rare for the Mid-Atlantic region to have Winter temperatures that low.

I don't know why the car uses the juice it does, but I once parked at a supermarket for an hour and a half on my way to a supercharger and the battery dropped 5% (~5kWh)! Clearly there are times when the car sucks power. There are recommendations to keep the car plugged in at all times, no?

 

[spamgoeshere2]

Don't worry about it. Don't park at the airport with less than 30% charge(and the more the better). Turn Sentry off if you don't mind, although it'll turn itself off at 20% remaining charge anyway.

Yeah, I was caught by sentry mode once and have it turned off now. I also got caught by the overheat protection and that's now off. Too bad these can't be controlled via the app. Well, I know the overheat can't be, not sure about sentry mode. I watched my car drop many percent a day until it reached 20% where it dropped more slowly. I ended up having to find a close by charger before I could head home in the middle of the night.

Sometimes an EV is just a pain in the ass! Being able to fill a gas tank in 5 minutes at any time, day or night, weekday or weekend, even on holidays is so nice! We are a LONG way from the roads and parking lots being EV friendly.

 

[roblab]

With 300 to 400 miles of range on these cars, I don't see how one might ever have to leave a car parked with much less than half a full charge. A half charge should last quite a while in a long term parking lot without needing a charge.

With so many superchargers everywhere, I also wonder why folks can't stop by the SC and charge before parking in the long term lot with nearly a full charge, which would guarantee a healthy battery even in long term parking.

Now, obviously, an airport long term parking lot will likely NOT have an outlet one could use for his/her EV, but arriving with a full charge should carry it over several days if not weeks.

The alternative would be to drive your gas car to the airport and abandon it there. Well, maybe not.

 

[spamgoeshere2]

Reading another thread I realized the issue with the airport can be summed up by, "Better is the enemy of good" - Voltaire

 

[Sophias_dad]

With 300 to 400 miles of range on these cars, I don't see how one might ever have to leave a car parked with much less than half a full charge. A half charge should last quite a while in a long term parking lot without needing a charge.

With so many superchargers everywhere, I also wonder why folks can't stop by the SC and charge before parking in the long term lot with nearly a full charge, which would guarantee a healthy battery even in long term parking.

Now, obviously, an airport long term parking lot will likely NOT have an outlet one could use for his/her EV, but arriving with a full charge should carry it over several days if not weeks.

The alternative would be to drive your gas car to the airport and abandon it there. Well, maybe not.

Not everyone gets an LR. Some have an SR or SR+, or they drive 100 miles to get to the nearest real airport. Even an LR3 is usually below 300 miles by a few months into usage, and that's assuming a charge to 100%

I'd agree that most Teslas should be able to sit for a few days or a week at the airport. That said, I'm sure every time I go to the airport it'll be with a considerably less valuable ICE with somewhat more cargo space than my 3. More than a 7-10 days and I'm likely to get a limousine service anyway, because it gets cheaper than parking.

 

[roblab]

Sometimes an EV is just a pain in the ass! Being able to fill a gas tank in 5 minutes at any time, day or night, weekday or weekend, even on holidays is so nice! We are a LONG way from the roads and parking lots being EV friendly.

Standing in the freezing wind with the sleety rain sticking to your face as you fill your gas tank is SO NICE! And that happens, too: I've been there. Filling my car in my garage lets me drive almost all day, and a short stop at a Supercharger tops me up in literally a few minutes. Hey, just like filling the tank, only nicer! Not needing to charge at an airport parking lot because I charged at home is so nice, too. (Why don't people arrive with a nearly full battery?? Is it really that far to the airport? Can't you charge on the way to the airport and the long term lot? I have questions!)

And filling your tank in "5 minutes" is also a dream, not even counting having to get the man to run your credit card. Of course, you might top off in five minutes, but probably not.

I've driven EVs for nigh on to ten years now, and have not experienced this pain you describe. My car's gas pump is an outlet in my garage. I don't have to drive to some freezing cold or boiling hot "station" to fill my tank once a week, and I get 400 miles of range when I do, full every morning. All of my gas cars couldn't do that, and there were many times I wished they could.

 

[spamgoeshere2]

With 300 to 400 miles of range on these cars, I don't see how one might ever have to leave a car parked with much less than half a full charge. A half charge should last quite a while in a long term parking lot without needing a charge.

I have a regular trip to the airport with a 2 to 3 hour drive. Given the unpredictability and the length of the drive I may or may not end up with the time to charge before parking. Just this week I was routed at the last minute 20 miles out of my way because of congestion and had to stop at a strange charger to at least get a few more kWh on before the airport. Even with keeping the charging short I barely made the flight.

Given my experiences with the car, I literally don't know what to expect if the car sits for a week in winter temps. So even starting with 40% on the car may not be enough.

With so many superchargers everywhere, I also wonder why folks can't stop by the SC and charge before parking in the long term lot with nearly a full charge, which would guarantee a healthy battery even in long term parking.

In the case of BWI there is only an Urban charger close to the airport in the direction I'd be coming. A Supercharger in Laurel, MD is a bit off the path requiring even more driving time during rush hour. I don't think many people are familiar with how bad traffic can be around Washington, DC.

What if the trip is two weeks, three weeks???

Now, obviously, an airport long term parking lot will likely NOT have an outlet one could use for his/her EV, but arriving with a full charge should carry it over several days if not weeks.

That's my point... some airports have outlets for other types of cars. If you drive a diesel car you don't park anywhere cold without a block heater running. Look at the cold snap they had in Texas last winter. That could have stranded EVs in long term parking. There's no reason to not make this available for EVs as well.

The alternative would be to drive your gas car to the airport and abandon it there. Well, maybe not.

Not sure what that even means. I drive an ICE in Puerto Rico because charging facilities are virtually non-existent. Even Tesla only has two superchargers on the entire 120 x 50 mile island. Large parts of the island are not accessible by EV unless you know someone with a 240V outlet. I read Tesla upped the price of the model Y some more so that a long range version is now a $60,000 car!

I have an X with a nominal 290 mile range. I won't buy another EV unless it has a 400 mile range because you never use the full range and many factors detract from that value to get a useable range which is at best less than 3/4 and more likely 2/3 of the quoted range.

 

[spamgoeshere2]

Standing in the freezing wind with the sleety rain sticking to your face as you fill your gas tank is SO NICE! And that happens, too: I've been there. Filling my car in my garage lets me drive almost all day, and a short stop at a Supercharger tops me up in literally a few minutes. Hey, just like filling the tank, only nicer! Not needing to charge at an airport parking lot because I charged at home is so nice, too. (Why don't people arrive with a nearly full battery?? Is it really that far to the airport? Can't you charge on the way to the airport and the long term lot? I have questions!)

And filling your tank in "5 minutes" is also a dream, not even counting having to get the man to run your credit card. Of course, you might top off in five minutes, but probably not.

I've driven EVs for nigh on to ten years now, and have not experienced this pain you describe. My car's gas pump is an outlet in my garage. I don't have to drive to some freezing cold or boiling hot "station" to fill my tank once a week, and I get 400 miles of range when I do, full every morning. All of my gas cars couldn't do that, and there were many times I wished they could.

You live in an ideal world where you plan every moment of your day I suppose. I don't need to stand in freezing rain to fill a gas tank. It's not much more than connecting the cable for my Tesla. I would connect the hose and swipe the credit card and get back in my truck. I'd get out again when the tank is full and I'd be off, literally 5 minutes later. Don't pretend charging an EV other than at home is remotely better than filling a gas tank. If nothing else Superchargers are still typically 25 to 50 miles away for no small number of people.

If you read my posts, you would realize I'm not describing running to the grocery store a couple times a week. I drive 125 miles to the airport using roughly 45% of my max charge. I don't charge the full 100% to avoid premature wear on the battery which is 6% down after a bit over 3 years. Six days later I drive 125 miles back to the house which absolutely requires a charge before reaching home. Starting in January, the car will be sitting for 8 days at a time. That's the time I'm worried about.

The problem is if the traffic is not ideal or if I have to make a side trip I end up with only 30% charge at the airport or as in the case of last week I only would have had 17% or so because of a confluence of factors, call it a "perfect EV storm", so I had to make an unplanned stop that almost made me miss my flight. The problem is not when everything happens as planned, but when things happen that weren't planned.

So don't assume every person lives the same life as you.

 

[Rocky_H]

I don't know why the car uses the juice it does, but I once parked at a supermarket for an hour and a half on my way to a supercharger and the battery dropped 5% (~5kWh)! Clearly there are times when the car sucks power.

Ah. That is not necessarily actually USING energy in that case. This has confused plenty of people before. They have been driving for a while, and then they park somewhere for an hour or two, and then are totally shocked to find that from when they parked to when they return to the car, it has suddenly changed by a few %. This is generally not from any energy actually going anywhere or being consumed. It is usually because the temperature of the battery changed. The cooling of the battery now reflects a bit less energy from the car's estimation algorithm, so it shows a bit less on the display.

There are recommendations to keep the car plugged in at all times, no?

Well sure, because they are trying to encourage good habits, because if people forget to plug in sometimes, and then they go to leave for work and find that the car doesn't have enough energy, they will be angry at the car and at Tesla and spouting to their friends and on Facebook and on Twitter about how these electric cars suck and are a pain in the ass, etc. etc. Tesla is trying to sell cars, so they encourage people to plug in often so they don't forget and get caught in a bad situation.

Also, there was a specific reason they have always included that message in the manuals. They were having to combat this weird false myth about electric cars that if they were left plugged in when they got "full", that the connection would continue to force feed electricity into it until they exploded! Yes, people believe that. I have actually seen threads here on this forum, where people were genuinely scared that they had to watch charging the whole time, and go RUNNING to the car to pull the plug to prevent it from blowing up. *sigh* So Tesla was having to reassure people that it is totally fine to have the car plugged in as much as you feel like, with no worries.

 

[spamgoeshere2]

Ah. That is not necessarily actually USING energy in that case. This has confused plenty of people before. They have been driving for a while, and then they park somewhere for an hour or two, and then are totally shocked to find that from when they parked to when they return to the car, it has suddenly changed by a few %. This is generally not from any energy actually going anywhere or being consumed. It is usually because the temperature of the battery changed. The cooling of the battery now reflects a bit less energy from the car's estimation algorithm, so it shows a bit less on the display.

That might seem to make sense superficially, such as going from 50% to 45%. But give it a bit of thought and explain how it can go from 5% to 0%! The cold would reduce the available range proportionally to the amount left. Dropping 100% is pretty hard to imagine. Even so, that is part of the problem I am addressing with the need for continuous power when long term parked. It doesn't matter how you classify the problem. It's still a problem!!!

Well sure, because they are trying to encourage good habits, because if people forget to plug in sometimes, and then they go to leave for work and find that the car doesn't have enough energy, they will be angry at the car and at Tesla and spouting to their friends and on Facebook and on Twitter about how these electric cars suck and are a pain in the ass, etc. etc. Tesla is trying to sell cars, so they encourage people to plug in often so they don't forget and get caught in a bad situation.

Also, there was a specific reason they have always included that message in the manuals. They were having to combat this weird false myth about electric cars that if they were left plugged in when they got "full", that the connection would continue to force feed electricity into it until they exploded! Yes, people believe that. I have actually seen threads here on this forum, where people were genuinely scared that they had to watch charging the whole time, and go RUNNING to the car to pull the plug to prevent it from blowing up. *sigh* So Tesla was having to reassure people that it is totally fine to have the car plugged in as much as you feel like, with no worries.

That seems to be a cyclical argument. People are concerned about leaving the car plugged in so tell them to leave the car plugged in which makes people anxious about leaving the car plugged in...

They tell you to leave the car plugged in so it deals with vampire drain and can keep the battery warm in cold weather.

 

[Big Earl]

There are three Superchargers within 10 miles and nine (soon to be eleven) within 25 miles of BWI.

Park with at least 60% and you're good to go for a month as long as you turn off Summon Standby and Sentry Mode, don't compulsively check the app (wake up the car), don't have third party apps pinging it, and don't accidentally turn the climate control on.

The car does not need to remain plugged in anytime it's parked and no damage will be done unless the vehicle is cold soaked in double-digit negatives for an extended period of time. Even with a polar vortex hitting our region, it'll be fine outside, unplugged, if you plan appropriately.

 

[RTPEV]

There are a few reasons for sudden drops in battery percentage shortly after parking that I don't think have been mentioned.

One is the the car's cooling systems that continue to run after you park your car, particularly after a long drive in hot weather. Not only is the car trying to manage the battery temp, but on an especially hot day the cabin overheat protection may also kick in. Both of these will eventually turn off, but there may be a few percent drop in SOC over a relatively short period of time due to this. You should not extrapolate that loss far out in time, however, as both of those systems will eventually turn off.

Another possible reason, and I'll say right from the start I don't have any first-hand knowledge that this is the case with Teslas, but it sure was with my LEAF (and I would be surprised if it didn't happen in Teslas--it's just that I've never monitored it this closely) is that when you turn off an EV, the BMS recalibrates the SOC of the battery, which may indicate a sudden shift in the SOC reading. When the battery is under load, SOC is only estimated by using coulomb counting (i.e. measuring how much current has been drawn from the battery). While quite accurate, you can't get a highly accurate indication of SOC until the battery is not under load. On my LEAF this would manifest as the SOC dropping by several percent a few minutes after I parked the car (it was quite a bit more noticeable in a car with only 80 miles of range to start!) This does not mean the battery suddenly lost that charge, it's just the indicated SOC that changed.

In addition to that, it's also not reasonable to assume that because the SOC appeared to drop from 50-45% after being parked for 30 minutes that the same would happen from 5-0%. Not only will be car turn off various systems at less than 20% SOC to conserve battery, the inaccuracy of the SOC estimation will be far less at lower SOC anyway.

Lastly, in response to a previous comment, yes, there are recommendations to keep the car plugged in always, but I've always felt that that was out of an abundance of caution rather than an actual requirement. I certainly don't follow this advice, but I've also had a lot of experience with EVs over the years and generally don't forget to plug in, and I usually keep my battery between 30-70% SOC, and when weather dictates, I may charge up even if it hasn't gotten down to 30%. In general, however, I don't worry about it.

 

[Rocky_H]

That might seem to make sense superficially, such as going from 50% to 45%. But give it a bit of thought and explain how it can go from 5% to 0%! The cold would reduce the available range proportionally to the amount left. Dropping 100% is pretty hard to imagine.

Ah. This has been covered in some other threads before. It is actually far MORE likely for this to happen at very low states of charge, not less. and no, it's not really proportional to the amount left. It has to do with the voltage curves of lithium ion batteries. If you look those up, they have an extremely flat voltage level through a big portion of the middle of the state of charge. That is one of the reasons why the car's range estimation algorithm has a tough time if the car is only used in that middle state of charge.

But at the high end, the voltage rises quickly, and at the low end, it drops off very quickly. So the car can get really twitchy about range in that low end of 5% or less. Accelerating hard, which puts a heavy draw on it, can suddenly pull the voltage down, which can suddenly show a swift drop in displayed range. And temperature adjustments, like cooling off can also cause it to drop quickly down that voltage slope. So yeah, it's much more of a thing at the bottom end than it would be in the 50% to 45% area.

That seems to be a cyclical argument. People are concerned about leaving the car plugged in so tell them to leave the car plugged in which makes people anxious about leaving the car plugged in...

That doesn't make any sense. People are worried because of the fear of the unknown. They have heard all kinds of rumors and fear mongering and FUD and scary stories from all kinds of people who may or may not know anything about it, so they don't know who to trust, so they are scared from not knowing what to do.

So for the manufacturer of a product to tell you exactly how to use it and what is appropriate and safe for it neutralizes all of that scary unknown. It is reassuring and calming and satisfying to know what is the right thing to do with that product. It would do the opposite of making people more anxious.

 

[spamgoeshere2]

Ah. This has been covered in some other threads before. It is actually far MORE likely for this to happen at very low states of charge, not less. and no, it's not really proportional to the amount left. It has to do with the voltage curves of lithium ion batteries. If you look those up, they have an extremely flat voltage level through a big portion of the middle of the state of charge. That is one of the reasons why the car's range estimation algorithm has a tough time if the car is only used in that middle state of charge.

I'm not sure you understand the curve. It is a curve of voltage for what is assumed to be a constant load but is more often a fixed resistance which only provides a constant load when the voltage is constant. In any event, as you say yourself, the steeper curve allows more precision in determining the state of charge, not less.

In any event, it constitutes a failure of the BMS to maintain an accurate measure of the state of charge which is what this is about. The fact that the voltage curve is steeper still does not change the fact that the cold will remove battery capacity proportionally to the amount of energy in the battery.

But at the high end, the voltage rises quickly, and at the low end, it drops off very quickly. So the car can get really twitchy about range in that low end of 5% or less. Accelerating hard, which puts a heavy draw on it, can suddenly pull the voltage down, which can suddenly show a swift drop in displayed range. And temperature adjustments, like cooling off can also cause it to drop quickly down that voltage slope. So yeah, it's much more of a thing at the bottom end than it would be in the 50% to 45% area.

It's hard to accelerate at all when the battery surprises you with 0% state of charge.

That doesn't make any sense. People are worried because of the fear of the unknown. They have heard all kinds of rumors and fear mongering and FUD and scary stories from all kinds of people who may or may not know anything about it, so they don't know who to trust, so they are scared from not knowing what to do.

You need to read the thread in context. "They were having to combat this weird false myth about electric cars that if they were left plugged in when they got "full", that the connection would continue to force feed electricity into it until they exploded!"

Now does the statement make sense?

So for the manufacturer of a product to tell you exactly how to use it and what is appropriate and safe for it neutralizes all of that scary unknown. It is reassuring and calming and satisfying to know what is the right thing to do with that product. It would do the opposite of making people more anxious.

That would be great, but Tesla doesn't tell you exactly how to use the car or how to best maintain the battery. There are many issues that require significant research on your own. I recall advice that the battery should never be charged to 100% for maximum battery life, then Musk says it's perfectly ok to charge to 100% when you need as long as it's "not too much". The only way a user can make sense of this is to be given some reasonable way to valuate the impact. Being told "it's ok to do sometimes" doesn't tell me diddly squat really.

Maybe you know about the temperature profile and how the state of charge is impacted at what temperatures? In particular I'm concerned about parking after a couple hours of driving with some amount of charge on the car and finding a very low remaining charge when I return a week later and the weather is now around 10 °F. At what point does the car heat the battery to prevent damage? Is there any data on how much the state of charge is impacted when cooled from operating temperature to an ambient of 10 °F as a function of the starting state of charge? I've not seen this in the manual. It creates anxiety for me.

 

[Rocky_H]

In any event, as you say yourself, the steeper curve allows more precision in determining the state of charge, not less.

But that was not the issue you were bringing up. You complained of the amount of energy changing very quickly when left to sit and settle. And that is exactly what it does when it is in that part of the line with the voltage change being very steep.

It's hard to accelerate at all when the battery surprises you with 0% state of charge.

Well, not really. As some people have pointed out, Tesla seems to have re-instituted the "below 0 buffer", where the car will usually have a bit left when the meter gets to displaying 0%.

You need to read the thread in context. "They were having to combat this weird false myth about electric cars that if they were left plugged in when they got "full", that the connection would continue to force feed electricity into it until they exploded!"

Now does the statement make sense?

I just reread it, in context, and yes, it absolutely makes perfect sense. This is what you said:

There are recommendations to keep the car plugged in at all times, no?

When you are driving the car, it obviously can't be plugged in. Sitting in a parking lot, it will frequently not be plugged in. The cars can sit for several days at a time without being plugged in, and they do not suffer harm from that either. "at all times" is definitely an exaggeration and not really what Tesla recommends exactly. But I was explaining why Tesla would give a recommendation similar to that about keeping the car plugged in excessively more than it needs. And having to fight that wives' tale misinformation about remaining plugged in leading to overcharging and exploding is one of the reasons they needed to say that, which was not related to idle drain energy consumption. So you brought it up, and I explained multiple reasons of why they published that type of recommendation. That was just one of them.

That would be great, but Tesla doesn't tell you exactly how to use the car or how to best maintain the battery.

Yes they do! As much as is really needed. It's the simplest way to get the best balance of most benefit for the most amount of people for the most use cases.
However, they are selling a consumer product. If they were to give excessive detail with many pages of steps and charts of various conditions and how to do things several ways to be the most perfect, it would have two negative consequences:

1. It would be problematic for some people's use cases, where they need to use their cars outside of what is the most "ideal" treatment of the battery. And then that would mount up to lots of calls and service visits with people trying to reconcile that contradiction between needing a car they can use but being concerned with violating these recommendations and conditions.
2. It would feed the FUD of the haters and the fears of those who just don't know but are scared and worried about new technology they don't understand that well. If it has complicated steps and conditions they have to remember, that will seem overwhelming and discourage them from considering buying an electric car. And they would continue spreading these negative rumors about how electric cars are too scary and complicated to use.

So for those reasons, Tesla doesn't want to go too over-the-top with making it complicated. They keep it pretty simple, with the 50% to 90% being OK for constant daily use, and above 90% being OK for occasional use. Simple. Don't worry people. If you park with a very low state of charge, it will display a simple message saying you should probably plug in. If you charge it up really full several times, it will also display a simple message saying it's not a good idea to do that a lot. Also simple.

There are many issues that require significant research on your own.

No. That is not required. If people never look any of that up or do that research, THEY WILL STILL BE FINE. It is not required to obsess like that.

I recall advice that the battery should never be charged to 100% for maximum battery life, then Musk says it's perfectly ok to charge to 100% when you need as long as it's "not too much". The only way a user can make sense of this is to be given some reasonable way to valuate the impact. Being told "it's ok to do sometimes" doesn't tell me diddly squat really.

As I just mentioned above, people don't need to look this up or worry about it. The car will give a simple message guiding you. It's fine. And really, this kind of seems like you're not being serious here. Plenty of things in life are known to be bad to do excessively or constantly--eating junk food, excessive alcohol, smoking, revving your car to redline, speeding. People moderate things all the time in their lives without having to know an exact quantified number of what the impact will be of doing it too much. "This generally isn't good; I shouldn't do it all the time."

Maybe you know about the temperature profile and how the state of charge is impacted at what temperatures? In particular I'm concerned about parking after a couple hours of driving with some amount of charge on the car and finding a very low remaining charge when I return a week later and the weather is now around 10 °F. At what point does the car heat the battery to prevent damage? Is there any data on how much the state of charge is impacted when cooled from operating temperature to an ambient of 10 °F as a function of the starting state of charge? I've not seen this in the manual. It creates anxiety for me.

I am sorry that you have so much anxiety about this, and I am trying my best to let you know that you DON'T need to obsess and worry about this so much. They designed these with extremely detailed systems to prevent people from being able to accidentally destroy them. It's the public--they know what the public is like. I wouldn't recommend what you are suggesting, of parking the car in the cold with a very low state of charge and then leaving it that way for a week. It's not that it's going to destroy the main battery, but just because you will probably cause yourself a lot of inconvenience.

If the car is really running low and can't get recharged, it will just keep the main pack disconnected, with a safety buffer of energy left in there (that you are never allowed to access) so that the battery will not be drained completely and harmed too much. The idle systems in the car will eventually drain the little 12V battery, so you will have to get service or a tow truck or something to deal with that hassle and maybe have to replace that 12V, but you can get it somewhere and get it charging, and it will be OK.