Battery to 0 overnight

[dhrivnak]

I am losing 1-2 miles of range in the Model3 over 24 hours... you really need to take that car in to service center and have it interrogated.

About a mile a day is par for the Roadster

 

[JRP3]

I don't know whether that is actually the case or not, but my guess would be that is only when the car is put into a deep sleep/low-power mode... just parking and walking away for a year (even on a mostly full charge) has too much vampire drain for that to be ok.

I think what happens is when the car discharges enough to get near the bottom buffer everything shuts down and there is no more vampire drain. You then need Tesla to "wake the car" back up. With no drain the cells should not discharge any further on their own. I have bare 18650 llithium cells that have been sitting for years and still show a charge.

 

[hacer]

I think what happens is when the car discharges enough to get near the bottom buffer everything shuts down and there is no more vampire drain. You then need Tesla to "wake the car" back up. With no drain the cells should not discharge any further on their own. I have bare 18650 llithium cells that have been sitting for years and still show a charge.

It is extremely likely that the balancing circuit is always connected to the cells thus this is not equivalent to an isolated cell.

Did your cells that sat for years start with a 3% charge? Just because they retain some charge doesn't mean they have anything like their original capacity

 

[Yuri_G]

I seem to remember Tesla saying a Model S can sit for a year or so without damage.

I remembered something similar, with some digging...

Model S batteries also have the ability to protect themselves as they approach very low charge levels by going into a “deep sleep” mode that lowers the loss even further. A Model S will not allow its battery to fall below about 5 percent charge. At that point the car can still sit for many months. Of course you can drive a Model S to 0 percent charge, but even in that circumstance, if you plug it in within 30 days, the battery will recover normally.

Plug It In

 

[rxlawdude]

I'm having my doubts about OP's story. Something doesn't pass the smell test.

And yeah, why would the cabin temperature be 40 degrees higher than ambient unless the owner told the car to stay heated (camper mode, using some 3P computer software that connects to the car, etc.)?

 

[mongo]

Actually it (inductance) is a big advantage. It allows pulse width modulation of the heating with a near DC current from the battery (which the inverter naturally does). This means that the model 3 battery heater is more versatile than that found in the S or X.

If you are trying to create a fine control buck converter inductors are handy. For the 3 which is relying on generating waste heat from the stator windings, the inductance is necessary to limit/ control the average winding current/ power dissipation.

For a bulk heating situation with wide temperature margins and high thermal mass, a properly sized heater element like the S or X have is perfectly functional. Turn on at the lows set point and off at the high set point, no need for an exact match to heat loss.

The 3 solution is lower cost and removes an entire HV circuit a long with control. An interesting side benefit is that if the 3's motor/ inverter can dissipate sufficient heat to replace the S/X dedicated 5-6kw heater, and the motor is normally say 90% efficient, it can handle a driving condition of 60kW indefinitely (80 hp) 3 to 4 times the typical load of 300 Wh/mile (@60 MPH = 18kW).
Another interesting thing is that pack heating is more effective when done at the cell level. However, they are designed to be low impedance, so it would take crazy amounts of current to warm them up. But, if you can pull the current, and then return it, you get double the heating with less loss. Doubtful the motor can store that much energy in the inductors, but fun to think about (FCC might frown on a 500A resonant tank circuit).

 

[ℬête Noire]

I'm having my doubts about OP's story. Something doesn't pass the smell test.

At first something seemed very off, and maybe still is. But when you view it as them being a never-owned-a-Tesla-before a lot more of this makes sense.

Also kinda underlines the wisdom of Tesla trying to keep ownership to people with prior Tesla experience.

And yeah, why would the cabin temperature be 40 degrees higher than ambient unless the owner told the car to stay heated (camper mode, using some 3P computer software that connects to the car, etc.)?

Model 3 doesn't have an official camper mode. That suggests this was a software bug, possibly involving the infamous phone-key. EDIT: There have also been reports of HVAC "self-activating", too, right? Something to do with touch screens, or is that Model S?

 

[ℬête Noire]

(FCC might frown on a 500A resonant tank circuit).

 

[Dr. J]

I expect SFInvestor21 is running off canned FUD talking points.

It's not just in cans.

 

[C141medic]

I'm having my doubts about OP's story. Something doesn't pass the smell test.

And yeah, why would the cabin temperature be 40 degrees higher than ambient unless the owner told the car to stay heated (camper mode, using some 3P computer software that connects to the car, etc.)?

Bitcoin miner

 

[pilotSteve]

FWIW myTM3 has been at the detailers shop (heated) for 5 days while I’m out of town and only discharged from 225 miles to 216 today. That’s the kind of drain I consider reasonable.

 

[Dr. J]

Question is why would the car maintain cabin temperature if it was off and not something that was selected or requested?

Possibilities: The car wasn't turned off. Or the cat was out driving it overnight. I would check the odometer.

 

[JRP3]

I remembered something similar, with some digging...



Plug It In

Yup, that's what I was thinking about.

 

[smartypnz]

After reading this and on a whim, I set my M3 to turn on the climate (we had a rare cold night last night and I did not drive today). It was cold in the cabin inside the garage (51 deg), but it heated up to 70 - no problem. Currently plugged into 110v.
However, decided to warm up the MS as it also was in the mid 50's. Set the climate to ON and gave it 70 degrees. After a minute - no action and then the indicator switched to "Turn On". In other words, it went back to the 'Off' state. Several retries later, I commanded the car to start charging (thinking a bad connection to our HPWC). After that I was able to 'Turn On' the climate to warm the car. After several degrees warmer, I stopped the charge and then the climate turned off. Again was unable to start it.

Is it normal to be only able to run the climate if Charging? I seem to remember successfully warming without enabling charging. Our temps don't normally warrant a need for 'pre heating' but I have done it before as a courtesy for my wife's early morning commute in the S.

Sorry to mention an S problem in a 3 thread.

 

[JRP3]

It is extremely likely that the balancing circuit is always connected to the cells thus this is not equivalent to an isolated cell.

Pretty sure that when the car senses extremely low SOC it shuts down everything. Balancing is only active near the end of a charging session.

Did your cells that sat for years start with a 3% charge? Just because they retain some charge doesn't mean they have anything like their original capacity

I didn't do a capacity check, just stating that they did not keep self discharging.

 

[Big Earl]

@Khangtn have you rebooted the car since this incident?

 

[cwerdna]

@Mulligan Jake : What's up with the disagree to my post at Battery to 0 overnight ? What is "correct" in your mind?

 

[CuriousG]

Possibilities: The car wasn't turned off. Or the cat was out driving it overnight. I would check the odometer.

 

[MikeBur]

Hey @jomo25, here you go.

Quick update! So I did end up leaving my car out last night, temperatures dropped as low as 28 degrees F. Car dropped from 132 to 117 Miles. Much better than 100 drop . Before I went to bed I did notice that my interior temperature was holding a solid 65-70 degrees as i monitored it for an hour (even though outside temp was 33). Before going to sleep I decided to switch off my Bluetooth maybe thinking proximity had anything to do with maintaining temperature or what others have said maybe my car is turning on and off. Anyways, happy it didn’t happen again for now.

Parked outside with the door ajar is my first guess, though that loss is still high assuming closed for this second time.

Couple of things I’ve determined from troubleshooting vampire loss drops on wife’s 3 is the sleep state on Model 3 is different than S/X.

• If you’re keeping the tesla app open, or using logging tools, then the car will not got to sleep - on an S/X it will as long as the “always connected” option is checked (this doesn’t exist on 50.12, maybe does on yours?).
• If the car is asleep and then needs to wake, eg to answer a API query, or respond to Bluetooth “key” proximity, it appears to wake up fully. It appears to take upwards of 5 minutes to go to sleep again.

One difference I’ve noted from charging is the rise in cabin temperature. Looking at your screenshot it’s saying 83F and I suspect you don’t have the climate that high. I’ve found this most pronounced when supercharging (up to 12degrees) and somewhat on 220V/32A+ (Up to 8 degrees). I suspect this has something to do with the way 3 dumps excess heat, and does that intelligently into an unoccupied car as the priority...?

Net: make sure that if you, or your parents for their car, are using logging tools, Alexa integration,etc turn then off and measure again (quick way to fix, ie if they might have played with these though can’t remember, is to change the main Tesla account password).

 

[MikeBur]

New meaning to “Valet Mode”