Low Mileage Charging Conundrum

[Marsnaut]

The general consensus is to leave the car plugged in with a low SoC when trying to store the Tesla for months at a time.

My situation is close but not exactly the same. I drive about 2k miles a year which equals out to almost 40 miles/week. There could be times when I don't drive up to a few days or even 2 weeks.

Is it ok to leave the car unplugged hovering between 50-75% and only plugging in when it drops below 50? Or is it better for battery health to leave it plugged in whenever possible?

 

[Zextraterrestrial]

I think it is better for battery if it is plugged in + then if you ever pre-condition it the power will come form the wall not the battery

 

[widodh]

Just set the max charge to 80% and charge every day. Keep it plugged in when possible

 

[AWDtsla]

50% and plugged in.

 

[TexasEV]

Tesla has answered this question in the owners manual. IN BOLD UPPER CASE TYPE LIKE THIS so it must be important. People really need to RFTM. It says to keep the car plugged in when possible.

What you’re describing is not “long term storage” when you set the charge to 50%. Just set your charge to 80 or 90% and don’t think about it again unless you’re going on a trip.

Just make it a routine when you get home to plug in. Don’t think about if you need it or not. Do you think about whether or not to plug your phone in at night based on how much you expect to use it the next day? Probably not.

 

[ReddyLeaf]

I just leave mine at 50% SOC and plugged into a 15A, 120 V plug. I drive the Leaf in town and only use the 70D for roadtrips. It might go days, weeks or months between trips. I don't know if it makes any difference in the battery life, but it doesn't impact my driving experience or use.

 

[eprosenx]

It seems to me that leaving it plugged in all the time is clearly the way to go (per Tesla's instructions).

The question in my mind is what is the optimal target state of charge given this use pattern? This is a pretty uncommon use case and so I am not sure Tesla has direct instructions on it. Generally I think they assume you want to use your care daily and for longer trips.

 

[TexasEV]

Define “optimal”. For all practical purposes it really doesn’t matter what he sets the charge level at, as long as it’s not 100%.

 

[Zextraterrestrial]

I think optimal for battery life would be keeping in the 50-60% range SOC

 

[AWDtsla]

It seems to me that leaving it plugged in all the time is clearly the way to go (per Tesla's instructions).

The question in my mind is what is the optimal target state of charge given this use pattern? This is a pretty uncommon use case and so I am not sure Tesla has direct instructions on it. Generally I think they assume you want to use your care daily and for longer trips.

As close as 50% for the longest amounts of wall time possible. Of course indicated 50% is actually slightly higher than real 50%.

 

[GSP]

@mastnaut,

For your usage I would leave the car plugged in with charge level set at 50%. That will be optimum for life, and plenty of range for your usage,

GSP

 

[TexasEV]

If you’re doing a battery experiment you may find a statistically significant difference, yes, but in real life with a Tesla I don’t think you’re going to see a meaningful difference no matter what charge rate you set. I and others charged a Model S to 90% daily for five years and didn’t see more range loss (5%) than anyone else.

 

[AWDtsla]

If you’re doing a battery experiment you may find a statistically significant difference, yes, but in real life with a Tesla I don’t think you’re going to see a meaningful difference no matter what charge rate you set. I and others charged a Model S to 90% daily for five years and didn’t see more range loss (5%) than anyone else.

The loss you see doesn't reflect real degradation. High degradation cars seems to have the car shut down early by nearly as much as the estimate at the top. In your case, you could guesstimate that as 10%.