!2v battery warranty

!2v battery warranty

My 85D needed a new 12v battery at 25000 miles/29 months. This was replaced under warranty. Now it says it needs another at 40000/50 months. That means the new battery has only lasted 15000/21 months. Asking at my local SC they reckoned a 12v battery would generally last 24-36 months. Question 1) is a replacement battery fitted less than 2 years ago covered by any warranty eg as a Tesla part? Question 2) anybody have experience of Tesla 'generosity' in such a situation? Question 3) any experience on how many months/miles a 12v battery should last? Question 4) Now the car is over 4 yrs old - any problems with fitting a third-party battery (last time, I had to wait several weeks for a Tesla part)? I am based in the UK but world-wide experience and views sought. At a smidgen under £200 very couple of years, this doesn't sound reasonable to me! BTW have looked at Ohmmu but that is $419 before Intl shipping and fitting....

Andrew Turner | 20 januar 2020


rob | 20 januar 2020

I'm not to the point that I need one yet for my M3 but I would consider this:

murphyS90D | 20 januar 2020

The battery is an AGM battery, not a wet cell lead acid battery. A wet cell battery would be totally wrong for this application because significant discharge damages a wet cell battery. They are designed to provide a 10 or 15 second burst of high current and then immediately be recharged. There are no high current demands in a Tesla on the 12 volt battery but it does get discharged to 50% at least 4 times a day if the car is parked. My car will be 4 years old in March and is still on the original battery. AGM batteries typically cost more than a wet cell battery.
Wet cell battery warranties run from 90 days to 8 years. Guess which costs more. I use an AGM battery in my 2013 Ford Fusion Energi, which I drive most of the time in electric only mode. I got 6 years out of the first one.

rxlawdude | 20 januar 2020

@rob, there's NFW I'd ever put that into my car (or let anyone I know do it). Looks like cheap Chinese junk. | 20 januar 2020

@Andrew - from various user reports, the 12v battery typically lasts from 18 months to 48 months - a rather wide band. Counter to what you might expect, those that drive the cars infrequently seem to be on the bottom end of the time, and those that drive a lot on the upper end of the time.

As I understand it, warranty part replacements are only covered for the period the car is in warranty. So if the battery died after 18 months, then 36 months and 54 months (with milage below 50K), the first two would be in warranty, and the last one would not. There have been some cases where Tesla covers something out of warranty as goodwill, but sorry to say I wouldn't count on it. | 20 januar 2020

Also, I agree with @rxlawdude - I would not recommend some other battery. The Tesla battery is selected to work with Tesla's unique operation - dramatically different than an ICE car. I also worry a lithium-ion 12v replacement may not work in the wide temperature ranges that the stock battery works, as it is neither heated nor cooled like the main battery pack.

murphyS90D | 20 januar 2020

I appear to be the exception to your statement.
I normally drive twice a week, 21 miles and 30 miles. My car spends most of its time in my unheated garage not plugged in. The car was built in January 2016 so it's 4 years old. No warning messages so far.

jordanrichard | 21 januar 2020

Ask any Porsche, Ferrari, Corvette, etc or collector car owner how long their batteries would last if they didn't have them plugged into battery tenders...........

Other than the bad batch of batteries Tesla got at one point, the overwhelming common denominator to short lived batteries is low usage.

As for throwing in some aftermarket battery, good luck with that.

sbeggs | 21 januar 2020

Except our original 12V, lasted five years and nine months, even with low usage of 36,000 miles. Car stays plugged in, and we charge low and slow at 15 amps, 240V at home. Not sure why ours was an outlier.

PBEndo | 21 januar 2020

I drive over 22K miles per year and I don't recall getting more than 2 years out of a 12V battery.

Stiction | 22 januar 2020

2015 85D
Battery failed after first 4-5 months and replaced under warranty. Replacement still going. I drive
about 10K miles/yr. I guess it should be going I just have it replaced proactively next time I'm
in service?

rob | 24 januar 2020

Note to self: heed the warnings

Beryl | 25 januar 2020

Tesla supposedly replaced my battery 12/06/19 under warranty. The “replace battery” message popped up on the dash on 01/13/20. My vehicle remained in the garage plugged in the entire month that it wasn’t being driven. I put on 109 miles. I requested the next available mobile appointment, 1/21/20. Tesla cancelled and rescheduled the appointment twice via text messages due to not having a battery in stock.

“Thank you for scheduling your Tesla for a Mobile Service Appointment. At this time, the parts needed for to address your concerns will not make it in time for your originally scheduled Mobile appointment. We are sorry for this inconvenience. I have rescheduled your appointment for 2/3 at 10:30 AM. Does this new date and time work for you? Please reply to this text with yes. If the new appointment date does not work for you, please login to your MyTesla APP and change your appointment for a date after 2/3. Thank you for your cooperation and please let us know if you have any questions. Thank you!

I hope the battery warranty is greater than 30 days. (They are not responding to my text responses.)

Haggy | 28 januar 2020

I had the same question since mine lasted under two years. It did get replaced under a parts warranty, but that was because the part that sits on top of the terminal was bad, and never should have been used (or reused as the case might have been) with the warranty replacement.

I was also told that the latest batteries with the latest software algorithms for charging it should allow it to last for five years. I don't know what sort of testing they did to conclude that.

If it failed after one month, I don't think there's any question about warranty. It's inconceivable that they won't replace it for free. Either the battery was defective or something else that connects to it or was touched at the same time was defective, connected wrong, not torqued properly or something similar.