Battery damage in extremely cold temps

[vman04]

Hi everyone.

I live in Chicago and we’re about to get some extremely cold temps here. Supposed to get down to -25F mid week. I typically leave my model 3 outside for about 8 - 12 hours at work (on and off charger depending on availability). Is there any risk of battery damage in these extreme temps?

 

[mrElbe]

-25F is not extreme! -40F or C is more like it. Just make sure you have a decent charge before parking it.

 

[duanra]

The owner manual says not to exceed more than 24hr at temp bellow -30c.

 

[ewoodrick]

Shouldn't damage, but don't expect it to have much capacity.

 

[ricohman]

The owner manual says not to exceed more than 24hr at temp bellow -30c.

Why is that?
We get this for a week or more at a time.

 

[duanra]

You get lower than -30c for 7 days non stop ? I will be surprised. Even when i lived in northern Quebec, it wasn't happening.
Don't factor the wind chill though.

 

[Big Earl]

The owner manual says not to exceed more than 24hr at temp bellow -30c.

Should be fine as long as it's plugged in to 240 volts for a period of time within that 24 hour period. Charging will actively heat the battery. 240 volts is important because at these extremely cold temperatures, 120 volts can't supply enough power to keep up with the battery heating and your state of charge will slowly go down.

I suspect the reason for this is to keep the electrolyte from freezing. The battery pack will automatically heat itself to prevent freezing, but this will consume energy from the battery. If this continues for too long, the high voltage battery pack will discharge to a point that it can no longer heat itself to prevent damage.

My advice for this type of cold weather is to keep the battery above 60% as much as possible and keep it plugged in whenever possible.

 

[coleAK]

We had -30 to -35F a couple of weeks ago when I was on my way to work. High that day was -15 though. Nothing dramatic happened. Pre heated for 30 min before I went home. As others have said, i charge every night when it’s that cold.

We haven’t had < -30 for days at a time yet but Fairbanks has, I know there are at least 3 Tesla’s in Fairbanks.

 

[strider]

As long as the battery has charge it'll protect itself. Assuming you don't need >50% range for your round trip you'll be fine.

 

[Tozz]

Hi everyone.

I live in Chicago and we’re about to get some extremely cold temps here. Supposed to get down to -25F mid week. I typically leave my model 3 outside for about 8 - 12 hours at work (on and off charger depending on availability). Is there any risk of battery damage in these extreme temps?

Actually, Li-Ion batteries like cold. If you Google on how to preserve your laptop battery you will read: "Charge it to 50% and put it in the freezer, it will last decades". And that is correct. Li-Ion batteries are best stored cold and preferably at 50% SoC.

However, be aware that Li-Ion don't like to get charged in freezing temperatures. The car knows this, so it will first heat up the battery before it starts charging. Because of this charging will take longer.

As @Big Earl has said I also believe the real issue could be the coolant freezing up if you leave it at more than -30c for a week. That would be a problem

 

[Tozz]

@outdoors: Perhaps explain your disagree? Everything I said is factually correct.

 

[outdoors]

@outdoors: Perhaps explain your disagree? Everything I said is factually correct.

Everything you said is factually correct. However this is not a Lithium Ion discussion. It is as titled:

Comparing all Lithium Ion batteries as same or similar in storage, usage, or charging is not correct, Doing this spreads information that is not factually correct by its association.

Saying a Model 3 battery because it is Lithium Ion is similar to a Laptop battery is like saying a Orange and a Lemon are the same because they are both Citrus fruits.
I bet a whole bunch of kindergartners served wedges would say they are very different. Which they are. So the laptop battery comparison is not applicable.

My disagree is because we have hundreds of thousands of new owners entering the EV marketplace both with Tesla and others. If even one of them says. "Hey I should just leave my car outside in -24F for two weeks because it is good for Lithium Ion batteries. Put them in a freezer Then your one liner has done no good.

Many people like to opine on the best, and the worst for batteries in equate their care to other Lithium Ion products(not EV's) on these forums. Those people doubtfully work at Tesla or if they were quoted 5 or 6 years ago.

This I would say is the best resource for ones Tesla and answers the OP's question. The owners manual:

Just read that first sentence in the manual under About the battery. Doubt any Laptop battery has that.

Edit: spelling of equate

 

[duanra]

True but it seems that the most important thing is too keep a safe level of charge. The easier way to achieve that is to leave the car plugged in. If you don't/can't you must make sure to charge it regularly
That is how i understand it.

 

[coleAK]

Everything you said is factually correct. However this is not a Lithium Ion discussion. It is as titled:

View attachment 372900

Comparing all Lithium Ion batteries as same or similar in storage, usage, or charging is not correct, Doing this spreads information that is not factually correct by its association.

Saying a Model 3 battery because it is Lithium Ion is similar to a Laptop battery is like saying a Orange and a Lemon are the same because they are both Citrus fruits.
I bet a whole bunch of kindergartners served wedges would say they are very different. Which they are. So the laptop battery comparison is not applicable.

My disagree is because we have hundreds of thousands of new owners entering the EV marketplace both with Tesla and others. If even one of them says. "Hey I should just leave my car outside in -24F for two weeks because it is good for Lithium Ion batteries. Put them in a freezer Then your one liner has done no good.

Many people like to opine on the best, and the worst for batteries in equitation their care to other Lithium Ion products(not EV's) on these forums. Those people doubtfully work at Tesla or if they were quoted 5 or 6 years ago.

This I would say is the best resource for ones Tesla and answers the OP's question. The owners manual:


View attachment 372901

Just read that first sentence in the manual under About the battery. Doubt any Laptop battery has that.

I agree. I’ll also add @Tozz. A freezer is no where near -22F. Usually closer to 0F.

 

[Tozz]

IMHO "most sophisticted battery system" is just marketing talk. It doesn't say anything about its characteristics or why it is more sophisticated then the average laptop battery.

But other than that, despite small chemical differences in Li-Ion batteries, the Model 3 also uses Li-Ion batteries. And the same applies to all: Li-Ion can handle cold very well, except for when you are charging. There really is no harm for the batteries in having the car sit in the freezing cold. The Tesla Model 3 batteries are a neat engineering trick, but they still are just Li-Ion batteries.

The manual page you quoted doesn't say it is bad for the battery to sit in the cold. It only says "Don't let it sit for days in -30 degrees" and warns about leaving it unplugged. Nothing more nothing less.

Li-Ion contain virtually no fluid. So they can't really "freeze" as in liquid that freezes (becomes solid). Li-Ion does show some affects in really cold temperatures (-40 degrees C), like degraded performance (lower discharge rate). But that is restored once the batteries are warmed up.

After your post I have done some extensive googling on li-ion in very cold temperatures (under -40 C) and I found _nothing_ that says it will degrade the battery. Plenty that say you should be careful with discharging it at those temperatures, but that is not something the driver should be worried about. The Tesla BMS takes care of that. It will heat up the pack, it will limit regen and possibly also limit acceleration.

The only real harm in my opinion is that automotive grade coolant will freeze at more than -40 degrees celcius.

Because of the coolant freezing I believe it is harmful to have the car sit in -40 degrees C or colder, because it might cause the coolant reservoir to crack and perhaps some coolant lines to break due to expension. This can be resolved by leaving the interior heating on (which will also heat the pack). So plug the car in, enable climate control from the App and you should be fine.

So all in all, in my opinion (which is, I believe, is based on facts):
- Li-Ion in the cold has affect on charge level. Leaving the car in the cold with low SoC could mean the car will shutdown due to the 12V not being charged. Make sure it's plugged in.
- In _really really_ cold temperatures (under 35 degrees c) it might be a good idea to turn on interior heating every other few hours to prevent the coolant liquid from freezing.
- I believe the "dont let it sit in under 30 degrees C) is due to the coolant freezing up (with a 10 degrees safety margin) and not due to battery issues.
- Driving the car in these conditions might severely impact performance. Not just in range but also because the BMS will put limits on charge and discharge rates.

Also, lets not forget: Any standard ICE car will also have issues in these extreme weather conditions. Diesel for example will freeze at -12C. To prevent this they add additives, but this only works up to -24 degrees C. In -30 degrees C your ICE car probably won't start. Also, same "coolant freezing up" issues occur with an ICE in -40 degrees C as well.

 

[taraquin]

We had -30 to -35F a couple of weeks ago when I was on my way to work. High that day was -15 though. Nothing dramatic happened. Pre heated for 30 min before I went home. As others have said, i charge every night when it’s that cold.

We haven’t had < -30 for days at a time yet but Fairbanks has, I know there are at least 3 Tesla’s in Fairbanks.

Did you get any regen after preheating?

 

[GSP]

@Tozz

Most Li-ion batteries have a liquid electrolyte, including Tesla's. Freezing the electrolyte will permanently damage the cells. This typically happens at about -40 degrees.

It will take some time for the large battery mass to cool and freeze the cells. Tesla’s warning to not expose to less than -30 C for over 24 hours is good advice. If I could not prevent that, I would make sure the car was plugged in, so that it could heat the battery.

GSP

 

[Tozz]

Most Li-ion batteries have a liquid electrolyte, including Tesla's. Freezing the electrolyte will permanently damage the cells. This typically happens at about -40 degrees.

The amount of liquid is tiny. As far as I am aware there is no lasting damage to the cells once they are are back to normal temperatures. Just don't charge or discharge them in those temperatures.

But yes, as you have said as well, having the car sit in less than ~ -30C to -40C is bad for more reasons than just the battery pack. My advise would also be to heat the pack (and thus the entire cooling loop) to prevent damage to other parts as well. For example, I don't know for which temperatures the electronics (MCU, EAP) are rated. Most electronics are not rated for temperatures that low.

Anyway, the -25F shouldn't be any problem. It's above the Li-Ion freezing temperature and above the temperatures at which the coolant will freeze.

I would like to add a reference to:
Battery warranty and temperature below -30C (-22F)

Which also states that there probably is no damage at all if you warm up the battery before using it. Note that the Tesla BMS will do that for you by preheating the car. So you don't need to take additional precautions except for heating the car before use.

 

[coleAK]

Did you get any regen after preheating?

I’ve had regen set to low since October. Most of the time I have full regen low when I leave after pre heat. Worst case I have it within ~5 miles driving

 

[coleAK]

IMHO
Also, lets not forget: Any standard ICE car will also have issues in these extreme weather conditions. Diesel for example will freeze at -12C. To prevent this they add additives, but this only works up to -24 degrees C. In -30 degrees C your ICE car probably won't start. Also, same "coolant freezing up" issues occur with an ICE in -40 degrees C as well.

Thanks for the info. But ^^^ isn’t really true. Anyone who lives in an area with an ICE that regularly sees these temps has a block heater, battery warmer and probably an engine blanket. Also they change out applicable fluids for ones with lower temp rating. I plug in block and battery if it’s <0 F. It would have been nice if Tesla had a cold weather package that added a 12v battery warmer, main battery warmer and coolant warmer. As for PG antifreeze when I traveled to Fairbanks and north regularly I mixed my own 60/40 that was good to -60F. “Slope” guys mix 70/30 that’s good to -80F. It took me ~30 min to do a full antifreeze exchange in my garage twice a year. Tesla says I can’t touch the battery fluid. I can’t imagine it’s all that complicated to change out. Would be nice if they gave guidance as to how to do it and if above mixtures are acceptable. And the trucks that run the slope all winter are diesel and they see temps well below -24C.

Anyway hopefully eventually aftermarket comes up with some plug in warmers for the Tesla.