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TMS cooling question when parked and not connected to a charger

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mdh

VIN 2747 P4679
Jul 30, 2012
128
0
Saratoga,CA
Will the battery TMS cooling system kick-on when the car is parked (turned-off) and not connected to a charger? My future Tesla S might be outside for a few days in the middle of summer. I am a concerned with accelerated battery degradation due to the heat and potential lack of cooling.

I assume the same answer applies to a cold winter day for warmth?

Thank you
 
Will the battery TMS cooling system kick-on when the car is parked (turned-off) and not connected to a charger? My future Tesla S might be outside for a few days in the middle of summer. I am a concerned with accelerated battery degradation due to the heat and potential lack of cooling.

I assume the same answer applies to a cold winter day for warmth?

Thank you

The Model S is always on and maintaing your battery temperature. It was use up a little more energy sitting unplugged for that long but the battery is large enough ( and you don't park it with a 5% state of charge before leaving for a long time) you'll be fine. Welcome to TMC too.
 
The Model S is always on and maintaing your battery temperature. It was use up a little more energy sitting unplugged for that long but the battery is large enough ( and you don't park it with a 5% state of charge before leaving for a long time) you'll be fine. Welcome to TMC too.

Thank you... i am about number 46XX... just got my configuration email... but, can't make up my mind if I really need/want the air suspension. My understanding is the non-air suspension will push me out until mid-end of January. I did an extended test drive and could not sense any "feeling" about having air suspension. In my mind (which could be way off), I've always seen problems with air suspension in high mileage cars. Any thoughts?
 
Thank you... i am about number 46XX... just got my configuration email... but, can't make up my mind if I really need/want the air suspension. My understanding is the non-air suspension will push me out until mid-end of January. I did an extended test drive and could not sense any "feeling" about having air suspension. In my mind (which could be way off), I've always seen problems with air suspension in high mileage cars. Any thoughts?
That is my thought also. There is a regular suspension retrofit kit made for EVERY model car that came standard with air suspension, along with complaints about longevity all over the Internet. There is a reason for that. What worries me even more is that continental(the supplier that Tesla uses) also supplied the kit for the Lincon Continental, which had/has constant problems with the air suspension. The cost to replace those is/was around $1500-2500 per wheel.
 
Does anyone know (or has Tesla published) how much energy will be used to self-cool the battery while unplugged?

No. A lot depends on the ambient temperature and the battery temperature so it's a moving target. I suspect once more Model S cars are delivered someone, not me, will develop a nomograph for the relationship between energy used, ambient temperature, and battery temperature.
 
Have you driven yet? Air suspension makes a huge difference.

I did an extended Tesla S test drive about one week ago... Frankly, I could not feel anything special about it... in other words, I could not tell if it was there or not. Tesla has not fielded any cars without air suspension so compare and contrast is not possible. Durability is very important to me... it sure seems like the high end luxury/performance market has stayed away from air suspension. Maybe for good reason... cost and durability? I am being told that my order will likely slip by 30 days if I don't go with air suspension.
 
it sure seems like the high end luxury/performance market has stayed away from air suspension. Maybe for good reason... cost and durability?

I'd say cost mainly. The air suspension I had around forty years ago was certainly durable. Until you've had a car with variable suspension, you won't know what you're missing.
 
Best way to charge for battery health? - Page 5

When it is summer here and I've been driving awhile, I'll come home and plug it in. Without charging, it still kicks in the fans I thought in an attempt to cool PEM and battery. It sounds like the Roadster will do some cooling if the pack heats up too much but not as much as when you start charging. I'd assume the Model S will make every attempt to keep battery pack within a certain temperature range when parked as well since allowing the pack to heat up too much can damage it. Maybe hcsharp or someone could provide more detail.
 
Is this different than Roadster? I don't think Roadster ever cools the battery when it's not "on."

Source(s), please.
My own experience. The one time I actually had the A/C divert from the cabin to the battery pack (last summer - rare here in the Bay Area) when I got home and got out of the car the fans and A/C kept running for 15 minutes or so. I believe the car will do everything it can to keep the pack below 40C (104F). Once it drops below that it will just run the pump until it gets down lower. Haven't stuck around long enough to check the temp when the pump quits (and now I have a Tattler and use its cooldown feature) but I had noticed the pump running for hours after a hot run.
 
We had record heat the day after I got the car. Of course I was giving everyone rides full throttle, and the pack got hot enough that it diverted the A/C. It also kept the A/C running for a bit after I parked. It would do that sometimes back then.

Ever since I had the heat exchanger upgrade, and they charged the freon properly, I've never had the A/C divert from the cabin, nor have I had the A/C run after I parked the car. And we had record heat all through the summer. Certainly the circulation pump has run after parking the car, and the PEM/motor fans have run, but not the A/C nor the main cooling fans.

(One thing I did notice with the new fans - when I've got the top down and the A/C starts up to cool the pack, I can feel hot air wafting over the top of the windshield!)
 
Here in the Phoenix area, I get Roadster cabin air diversion maybe twice in an hours driving most summer afternoons if the temps are in the low to mid 110's F. Usually lasts for about 5 minutes and then the cabin will get some cooling air again. That's not bad. On the few long trips I've taken, where I have to recharge on the road, the sustained driving seems to make the diversion kick in more often. Also, I've found it's important to try to find shaded charging spots in the RV parks. Direct sun light seems to make the 50 amp circuit breakers trip more readily and also extends the charging time significantly because more cooling is required.
 
I just thought of something: Tesla advertised that Model S can go without plugged in for a year without damaging the battery. This doesn't seem right, let's say the car is unplugged in hot Arizona summer for an extended period of time. The TMS has to kick in to cool the battery (ambient temp is 95F avg, cooling the battery to 80F or less) and this will in turn drain the battery until the TMS can't cool the battery anymore. This could probably only take a few days to occur, as I can't imagine the battery can last that long (even with 85kwh pack) with the TMS turned on. So you could have a situation where the battery (near empty) is sitting at high ambient temperature for a few weeks, and this can't be good for the battery, right?
 
I just thought of something: Tesla advertised that Model S can go without plugged in for a year without damaging the battery. This doesn't seem right, let's say the car is unplugged in hot Arizona summer for an extended period of time. The TMS has to kick in to cool the battery (ambient temp is 95F avg, cooling the battery to 80F or less) and this will in turn drain the battery until the TMS can't cool the battery anymore. This could probably only take a few days to occur, as I can't imagine the battery can last that long (even with 85kwh pack) with the TMS turned on. So you could have a situation where the battery (near empty) is sitting at high ambient temperature for a few weeks, and this can't be good for the battery, right?

Of course not. Just because it might last for a year without bricking, doesn't mean it's going to be happy about it. I suspect that Tesla was not referring to a year in a hot climate either. It seems to me the idea was that you could leave it at the long term parking lot at the airport and it wouldn't be worse for wear for a normal one-to-four-week trip, and even if you abused it by leaving it longer, it would still be okay. Of course, it would be far better (and perhaps cheaper) to take a taxi to the airport. And my guess is that long term airport parking will eventually have spots with connectors so you can leave it plugged in (for an additional fee).
 
I just thought of something: Tesla advertised that Model S can go without plugged in for a year without damaging the battery. This doesn't seem right, let's say the car is unplugged in hot Arizona summer for an extended period of time. The TMS has to kick in to cool the battery (ambient temp is 95F avg, cooling the battery to 80F or less) and this will in turn drain the battery until the TMS can't cool the battery anymore. This could probably only take a few days to occur, as I can't imagine the battery can last that long (even with 85kwh pack) with the TMS turned on. So you could have a situation where the battery (near empty) is sitting at high ambient temperature for a few weeks, and this can't be good for the battery, right?
Where are you getting 80F? Based on Roadster experience 40C (104F) is the point at which the car will attempt to actively cool the battery while sitting still. Yes, it's gets hotter than that in AZ but it's much easier to keep the pack at 104F than 80F so the battery should last awhile in that case. Also, the battery has a lot of thermal mass, so it takes awhile for heat to move into the pack. Hopefully Tesla let one site in the AZ sun for awhile and measured its draw before making the storage estimates. But bottom line, keep it plugged in whenever possible.
 
Where are you getting 80F? Based on Roadster experience 40C (104F) is the point at which the car will attempt to actively cool the battery while sitting still. Yes, it's gets hotter than that in AZ but it's much easier to keep the pack at 104F than 80F so the battery should last awhile in that case. Also, the battery has a lot of thermal mass, so it takes awhile for heat to move into the pack. Hopefully Tesla let one site in the AZ sun for awhile and measured its draw before making the storage estimates. But bottom line, keep it plugged in whenever possible.

I recall reading somewhere (probably from Volt forum) the optimal temperature range for Lithium Ion batteries is between 50 to 85F, so I assume the battery should be kept at this temperature range for maximum life. Chevy Volt's TMS kicks in when the battery pack temperature hits 85F and SoC > 75% while unplugged. I live in AZ will definitely will always plug in whenever possible, just worried about rare cases like going out of town for 2 weeks, the breaker is tripped and no TMS for 2 weeks could be bad for the battery.
 
I recall reading somewhere (probably from Volt forum) the optimal temperature range for Lithium Ion batteries is between 50 to 85F, so I assume the battery should be kept at this temperature range for maximum life. Chevy Volt's TMS kicks in when the battery pack temperature hits 85F and SoC > 75% while unplugged. I live in AZ will definitely will always plug in whenever possible, just worried about rare cases like going out of town for 2 weeks, the breaker is tripped and no TMS for 2 weeks could be bad for the battery.
Interesting data point. After I've driven the car and it's warm but below 40F it will run the coolant pump for awhile to bring the temps down (and to make sure the temps are constant throughout the pack - no hotspots) but as I posted above never stuck around long enough to see when it cut back off. I don't recall ever coming out after sitting awhile to find the car cooling (but it's not very hot where I live).

Bottom line is that we have to believe Tesla has figured out a way to have the car protect itself - battery management is Tesla's most prized knowledge and it seems as if they do it better than anyone else.