Model S sitting in storage for over a year. Is the battery damaged?

[HealthyDude]

Thanks to all in advance for any wisdom and guidance for a newbie. I am contemplating purchasing a used model S that apparently hasn’t been driven for over a year and was sitting in storage during this time period until now. My concern is that I don’t want to buy a car that may require a major unexpected investment...like a new HV battery. Any thoughts on the possibility of damage and what I need to do to vet this out and protect myself? Are there other things I should be concerned about as well?

It’s worth mentioning that the car is no longer within the 4 year bumper to bumper warranty. It is, however, within the 8 year battery and drivetrain warranty. I’m not sure if the actions of the current owner would possibly void the warranty either.

By the way, I don’t yet know if it was left unplugged (not charging) the whole time...or if it was plugged in and charging. Also, the owner just recently took it into have it serviced at the service center and they replaced the MCU (remanufactured version 1), performed some recalls, and replaced the 12v battery.

I would like to get a pre purchase inspection, or at least speak with a Tesla technician about this, but the service center won’t call me back.

Many thanks again for any advice.

All the best,
Future Tesla owner

 

[Tam]

...8 year battery and drivetrain warranty...

If the battery was plugged-in, it should be fine. You can see its State of Charge by the picture of its instrument cluster.

The owner's manual instructs drivers to plug-in when not driving.

It further says: "Never allow the Battery to fully discharge."

The warranty does not cover acts of sabotage when drivers don't follow the owner's manual.

If the battery was not plugged in, it most surely is permanently damaged by now.

You can attempt to file a warranty but Tesla will find the cause and most likely will not cover it due to breaching the terms of use.

If that's the case, you are lucky that the price has gone down quite a bit, about half price.

It used to cost around $44,000 for an 85 kWh battery but now it's just over $21,000!

Good luck!

 

[joltheadq]

more than likely not damaged. If completely dead, just needs a 12V jump and then plug up and charge traditionally. With current software, the BMS should balance and detect faults if present. Will the capacity be lower than usually? Probably. Will the battery performance be effected? Maybe. But I would suspect only temporary for both. Once the cells get good and calibrated with full charge/discharge, it should be a much healthier pack. I'd recommend keeping the SOC of the battery between 60-40% continuously if daily driven because that tends to be the sweet spot for reversing dendrites and chemical wear&tear. There are several rough estimate iPhone apps that can round out the total kwh capacity of the battery to give you a rough estimate of battery capacity. i.e. Tesla remote.
Other than that, I wouldn't sweat too much about it.

 

[joltheadq]

You can also ask the https://electrifiedgarage.com

 

[HealthyDude]

Thank you, Tam!

 

[HealthyDude]

You can also ask the TESLA ELECTRIC VEHICLE SERVICES

Thanks joltheadq!

 

[BigNick]

If the car was stored plugged in at a SOC higher than 50% for a full year, there might be some higher-than-usual battery degradation as well.

 

[ewoodrick]

Shouldn't be, there's some buffer built in. It's a common type situation for auction cars

 

[Darmie]

interested to know how you fair out. Following the thread.

 

[sorka]

It used to cost around $44,000 for an 85 kWh battery but now it's just over $21,000!

Good luck!

When did Tesla ever quote $44K for a new battery. I've seen nothing but $21K to $22K quoted as full price since 2012.

 

[Tam]

When did Tesla ever quote $44K for a new battery. I've seen nothing but $21K to $22K quoted as full price since 2012.

It's from the 2013 article reporting about upgrading a perfectly good 60 kWh to 85 kWh battery:

Life With Tesla Model S: Battery Upgrade From 60 kWh To 85 kWh

 

[Electric700]

Thanks joltheadq!

Welcome to the forum! If you can test drive it and also look at the display after a 100% charge (it should be driven immediately afterward, since 90% and below is better for the battery), you can see the maximum range. It should be close to 270 miles for a 90D with Rated Range enabled in the center screen. To see what the range was when new for other Teslas, you can also check this site:

2015 Tesla Model S AWD - 90D

 

[HealthyDude]

If the car was stored plugged in at a SOC higher than 50% for a full year, there might be some higher-than-usual battery degradation as well.

 

[HealthyDude]

Thank you!

 

[Lasttoy]

The main battery might be empty, and 12v? Get a super jump of more than 14.5 volts, wait 30 minutes, car should come to normal life. My 12v system crashed Thanksgiving, help desk got me up by this method. Put me on super charge and hour later I was fine. Have been ok since. Battery sitting should be fine unless in minus degrees?

 

[HealthyDude]

The main battery might be empty, and 12v? Get a super jump of more than 14.5 volts, wait 30 minutes, car should come to normal life. My 12v system crashed Thanksgiving, help desk got me up by this method. Put me on super charge and hour later I was fine. Have been ok since. Battery sitting should be fine unless in minus degrees?

Many thanks to all for your advice. The seller bailed at the last minute and wanted to sell it to one of her relatives at a higher price....even after I provided a deposit and already coming to a verbal agreement. Very strange. All for the best since I am taking delivery of a 2019 inventory performance model S tomorrow.