"Proactive" 12v battery replacement - good idea or overkill?

[KenC]

Would a small 12V Li-Ion/LFP battery work? Like a Shorai LFP designed to replace a motorcycle battery? They're designed for about the same 12V charging profile according to the battery OEMs.

I'm counting on it. I carry a small Noco in the frunk, and a 9V in my pocket.

 

[gearchruncher]

and a 9V in my pocket.

That's dedication!
I'd personally just tape a 9V inside the front bumper or somewhere if I was worried.

 

[stopcrazypp]

I'm counting on it. I carry a small Noco in the frunk, and a 9V in my pocket.

An A23 12V cell (or two in parallel just to be safe) also works and may be a better option as it takes up less space and can be stashed in the tow hook area.

However the issues people talk about are error messages that pop up if using LFP for permanent solution as opposed to something like jumping the car or temporary.

 

[one2many]

I'd personally just tape a 9V inside the front bumper or somewhere if I was worried.

I would love to see the face of a BMW delivery where they hand the owner a
9V battery and tell him to tape it to the bumper somewhere.
Sorry pot hole.

 

[texas_star_TM3]

OTA Software update.

all they need to do is more frequently float the

I'm counting on it. I carry a small Noco in the frunk, and a 9V in my pocket.

same here. great product and even if you do not need it - you can help someone jumping their ICE 12V battery or use it as an emergency power bank.

 

[gearchruncher]

I would love to see the face of a BMW delivery where they hand the owner a
9V battery and tell him to tape it to the bumper somewhere.

You should watch the latest Rich Rebuilds where he can't even get into his BMW i8 because it requires electrical power to open the doors, trunk, and frunk, and his battery is dead. At least our cars were designed with a spot and method to open them up!

But all this is completely silly because it's all based on someone being worried their battery will die and strand them somewhere, which can happen with a BMW or any other car also. Tesla isn't telling anyone to do this. And just like any other car, if you have another car with 12V and jumper cables, you can get the car going.

 

[one2many]

All I am saying its a pot hole, no 9V no happiness.

 

[KenC]

An A23 12V cell (or two in parallel just to be safe) also works and may be a better option as it takes up less space and can be stashed in the tow hook area.

However the issues people talk about are error messages that pop up if using LFP for permanent solution as opposed to something like jumping the car or temporary.

Actually, I carry two batteries, the 9v and a A23 12v, I just didn't mention it. I'm tempted to tape it behind the tow hook instead of carrying it, but I fear it'll eventually die. Okay, you convinced me, I'm going to go out right now and tape it behind the tow hook. My luck, when I need it, it'll be dead too.

Okay, it's done. 12v taped behind tow eye cover. 9v goes in my pocket!

 

[RayK]

Okay, it's done. 12v taped behind tow eye cover. 9v goes in my pocket!

Just don't put any coins in the same pocket as that is just asking for the 9V to short.

 

[Need]

And here I am just carrying an AAA card in my wallet.

 

[FloridaGary]

My 2015 P85D, two year and 56,000 miles-No battery replacement when turned in on lease. 2016 90D My battery final went out after 5 years and 120,000 miles, all in HOT Sacramento Summers and COLD Tahoe Winters. I attribute the longevity to consistently having the car plugged in.

My 2015 MS was plugged in every night and unfortunately it did nothing to extend the life of my 12v batteries in the MS or my current M3.

 

[gearchruncher]

My 2015 MS was plugged in every night and unfortunately it did nothing to extend the life of my 12v batteries in the MS or my current M3.

That is expected. The management of the 12V battery doesn't depend on being plugged into the wall at all. The 12V battery charges off the HV battery whenever it needs to, and the car will go to sleep (meaning it runs just off the 12V) when plugged in after charging is done.

 

[dhrivnak]

4 1/2 years and 86,000 miles on the original battery. Hopefully I will get the alert before a problem.

 

[Krash]

5 years 105,000 miles and counting on my Model S’ first 12v.

I wonder what the record is for most time and most miles?

 

[dhrivnak]

4 1/2 years and 86,000 miles on the original battery. Hopefully I will get the alert before a problem.

Well I jinxed myself as at 87,000 miles I got the alert, 400 miles from home Saturday afternoon when we were to travel home Sunday afternoon. So I purchased a 51R replacement and easy replacement and no more errors.

 

[metroplex]

How much did you pay for the Duralast? Costco and Wal-Mart have the best prices for Interstate and EverStart respectively. Usually $99 instead of the $150-$200 places want for flooded lead-acid batteries nowadays.

 

[SpGator]

2nd time Tesla replaced my 12v battery in under 8months. I went ahead and ordered some a23 batteries and will tape them in the tow hook compartment and keep my portable jumper in the frunk.

 

[abax]

What if you're locked out of the car? My understanding is an a23 won't open the frunk if the car is locked. How do you get access to jump?

2nd time Tesla replaced my 12v battery in under 8months. I went ahead and ordered some a23 batteries and will tape them in the tow hook compartment and keep my portable jumper in the frunk.

 

[RayK]

The procedure is printed in the owner's manual under the section titled: Opening Hood With no Power

edit: Fixed link to open page at the appropriate section

 

[SpGator]

What if you're locked out of the car? My understanding is an a23 won't open the frunk if the car is locked. How do you get access to jump?

If the 12v battery is dead, the a23 12v batteries will open the frunk once connected to those wires. If that 12v battery still has juice, then yes, those batteries won't open the frunk unless its unlocked.