What's the best 12V jump starter to keep handy?

[PhilDavid]

Cost and mostly likely supplier demand issues.

OEM costs about $140 + $400 in labor to install source:
12V Battery Replacement Cost
Lithium costs $440, I had Tesla install in when I was still under warranty, I paid the battery and they provided the labor at no cost.

It still doesn't make sense though. The replacement brand name AGM batteries for our ICE cars have cost around $250-300 (higher cost than standard batteries). The battery you recommended is $440 retail but I bet Tesla can buy them in bulk for half that price -- or for that matter, they probably have enough battery knowledge in house to make their own batteries!

But it seems their future roadmap is to build this capability into the battery pack to handle a redundant power supply that does not need a separate 12V battery. Just eliminating the 12V battery will likely yield them about $70,000,000 in savings for 500,000 units a year!

I just asked because it seems the 12V battery is an unnecessary weak point that can completely leave you stranded and this is why we just bought an emergency 12V battery to have handy. Also the road side service calls and replacement 12V batteries and the labor to install them is also costing Tesla so factoring all this it seems the battery you recommended would at least be very close to cost neutral.

 

[Xenoilphobe]

It still doesn't make sense though. The replacement brand name AGM batteries for our ICE cars have cost around $250-300 (higher cost than standard batteries). The battery you recommended is $440 retail but I bet Tesla can buy them in bulk for half that price -- or for that matter, they probably have enough battery knowledge in house to make their own batteries!

But it seems their future roadmap is to build this capability into the battery pack to handle a redundant power supply that does not need a separate 12V battery. Just eliminating the 12V battery will likely yield them about $70,000,000 in saving for 500,000 unites a year!

I just asked because it seems the 12V battery is an unnecessary weak point that can completely leave you stranded and this is why we just bought an emergency 12V battery to have handy. Also the road side service calls and replacement 12V batteries and the labor to install them is also costing Tesla so factoring all this it seems the battery you recommended would at least be very close to cost neutral.

I completely agree with you, I have never understood the need for a 12 volt battery, unless it plays a role to buffer or protect the DC to DC inverter and you are correct Tesla does have the technical knowledge to develop these, especially with the Giga Factory online.

All true, they need to hire you as a product manager - this all makes sense to me. The greater benefit is making the car more resilient and reliable and reduce service calls..

 

[mspohr]

I completely agree with you, I have never understood the need for a 12 volt battery, unless it plays a role to buffer or protect the DC to DC inverter and you are correct Tesla does have the technical knowledge to develop these, especially with the Giga Factory online.

All true, they need to hire you as a product manager - this all makes sense to me. The greater benefit is making the car more resilient and reliable and reduce service calls..

You are correct. Without the 12v battery, the DC converter would have to run all the time.

 

[quickstrike12]

This is a very interesting discussion. I’ve wondered these things also and would gladly pay for a better battery to be put in. Wish I had more answers first tho.

Please forgive me if this is a dumb question but could the reason be that a lithium battery mounted in the crumple zone of the car is more at risk of causing fire in the event of an accident? The main battery is obviously protected in in many ways. But the 12V one is not.
I’m no battery expert but I thought that was one down side of using lithium 12V in cars?

 

[Xenoilphobe]

Could have something to do with that. The battery is placement in newer Model S's is in very well protected at the rear of the frunk and high up close to the windshield and behind the front wheels. It would take one hell of an accident to get to the battery and the battery has a several key safety features just in case this does happen:

SAFETY & PROTECTION
Built in Automatic Battery Protection System Internal
Automatic Low Voltage Disconnect 8V
Automatic Short Circuit Protection Instant
Automatic Over Voltage Protection 15.8V
Automatic Reverse Polarity Protection Instant
Internal Cell Thermal Safety Fuse Yes
Flame Retardant Electrolyte Yes
Length Way Circuit Boards Yes
Automatic Internal Cell Balancing Yes
Automatic Fault Recovery Yes
Explosion Proof Stainless Steel Cells Yes

Source: 12V 50 AH Lithium Ion Battery | Deep Cycle Lithium Ion Battery | Smart Battery

 

[iCharge]

This is a very interesting discussion. I’ve wondered these things also and would gladly pay for a better battery to be put in. Wish I had more answers first tho.

Please forgive me if this is a dumb question but could the reason be that a lithium battery mounted in the crumple zone of the car is more at risk of causing fire in the event of an accident? The main battery is obviously protected in in many ways. But the 12V one is not.
I’m no battery expert but I thought that was one down side of using lithium 12V in cars?

this is a good thought, and may be the actual reason why its still LAB in a Tesla. LAB are time proven to be safe.
I can only wonder, for that 1 case in a million, when the 12V LiPo would get punctured, and may be result in a fire, it would be all over the news.

Here is a few examples on from YouTube, the first one of which I believe is the same type of cell [LiFePO4] as linked above

Another example with kitchen knife

 

[iCharge]

It still doesn't make sense though. The replacement brand name AGM batteries for our ICE cars have cost around $250-300 (higher cost than standard batteries). The battery you recommended is $440 retail but I bet Tesla can buy them in bulk for half that price -- or for that matter, they probably have enough battery knowledge in house to make their own batteries!

But it seems their future roadmap is to build this capability into the battery pack to handle a redundant power supply that does not need a separate 12V battery. Just eliminating the 12V battery will likely yield them about $70,000,000 in savings for 500,000 units a year!

I just asked because it seems the 12V battery is an unnecessary weak point that can completely leave you stranded and this is why we just bought an emergency 12V battery to have handy. Also the road side service calls and replacement 12V batteries and the labor to install them is also costing Tesla so factoring all this it seems the battery you recommended would at least be very close to cost neutral.

found this[ although it is a promoted video ]

 

[PhilDavid]

found this[ although it is a promoted video ]

Great video! Thanks for sharing.

So now I have a new question. God forbid my 12V battery dies, I was hoping with my fancy emergency battery that I can jump the car and drive to safety but as I to understand that while I can initially power all the electronic with the jump battery that I can't keep driving if the 12V battery goes bad?

 

[mspohr]

Great video! Thanks for sharing.

So now I have a new question. God forbid my 12V battery dies, I was hoping with my fancy emergency battery that I can jump the car and drive to safety but as I to understand that while I can initially power all the electronic with the jump battery that I can't keep driving if the 12V battery goes bad?

Most of the time people get warning that the battery needs to be replaced. Early (2012-2013) cars had sudden failures requiring jump starts. Since then, Tesla has changed battery suppliers and tuned the charging algorithm so sudden failures are rare.
Your jump starter can maintain the 12v battery to get you home but you probably won't ever need it. I have one and still have my original 12v battery after 4 years and have never needed it.
I'm sure my battery will fail someday, probably gracefully.
Don't worry. Enjoy the car.

 

[iCharge]

Great video! Thanks for sharing.

So now I have a new question. God forbid my 12V battery dies, I was hoping with my fancy emergency battery that I can jump the car and drive to safety but as I to understand that while I can initially power all the electronic with the jump battery that I can't keep driving if the 12V battery goes bad?

Mspohr is correct. MS relays all data to mothership about health of various (electronic) components. one of my friends had a Tesla technician call to schedule to change his 12V battery while he was a away because the car phones the mothership. It was getting low on the 12 volt battery this was on an older MS.

 

[PhilDavid]

Mspohr is correct. MS relays all data to mothership about health of various (electronic) components. one of my friends had a Tesla technician call to schedule to change his 12V battery while he was a away because the car phones the mothership. It was getting low on the 12 volt battery this was on an older MS.

That's good to know. Just don;t ever want to be stuck somewhere because of the silly 12V battery...

 

[BobChaput]

The 12v battery goes dead:
- when it is too old to accept a charge from the HV pack - Leave the charger on the 12v to until you get a new battery... can probably go a considerable distance since the HV pack will keep the old battery and the booster battery charged... in this case there is usually ample warning from the car that your 12v battery is going bad.
-when there is a problem with the 12v charging from the HV pack - Leave the charger on the 12v to get home or the service center... needs to be repaired immediately
- when the HV pack is dead - In this case, you aren't going anywhere on 12v... you need to charge the HV pack

I seem to remember reading somewhere that once the car is "started" the jumper pack can be removed and the car driven. True/false?
Obviously when the care is put into park and the vehicle exited you would be back in the same situation.

 

[mspohr]

I seem to remember reading somewhere that once the car is "started" the jumper pack can be removed and the car driven. True/false?
Obviously when the care is put into park and the vehicle exited you would be back in the same situation.

I don't know. If the battery is weak the voltage could drop quickly even when driving. Might be a problem.

 

[murphyS90D]

I seem to remember reading somewhere that once the car is "started" the jumper pack can be removed and the car driven. True/false?
Obviously when the care is put into park and the vehicle exited you would be back in the same situation.

Once the car is on the DC to DC converter will supply the 12 volts and attempt to charge the 12 volt battery. If the 12 volt battery has no capacity left it will die again when the car is off. Keep the HVB well above 20% if the 12 volt is in trouble.

 

[tccartier]

You guys revived a thread that was nearly 2 years old prior to today the last post was in November of 2018. I had forgotten all about this thread until it popped up that it contained new posts. The OP is probably long gone.

 

[PhilDavid]

You guys revived a thread that was nearly 2 years old prior to today the last post was in November of 2018. I had forgotten all about this thread until it popped up that it contained new posts. The OP is probably long gone.

Hey! I'm not "long gone!" I'm still around

I'll be around at least until they fix the USB audio and Spotify muisc player

 

[chilushah]

Re-igniting this thread. The Weakest link in Tesla is the 12V Battery. Does anyone know which jump start battery to buy off amazon. Almost all of them are disigned for ICE engines which provide a peak current during jumpstart but that is not required for an EV. ...

Taclife is one brand...

 

[mspohr]

Re-igniting this thread. The Weakest link in Tesla is the 12V Battery. Does anyone know which jump start battery to buy off amazon. Almost all of them are disigned for ICE engines which provide a peak current during jumpstart but that is not required for an EV. ...

Taclife is one brand...

I carry a lithium jump start battery just in case (some Amazon chinesium brand). I don't think it matters much since the current draw shouldn't be great. I've never had to use it.
My car is six years old now with original battery and no sign of problems... but it's nice to have that insurance.

 

[tccartier]

I carry a lithium jump start battery just in case (some Amazon chinesium brand). I don't think it matters much since the current draw shouldn't be great. I've never had to use it.
My car is six years old now with original battery and no sign of problems... but it's nice to have that insurance.

I don't think it matters much the brand. Just so long as it can supply 12 volts enough to bump your battery and get the main contactors to close which would energize the DC to DC inverter then you're off and running. Be advised however carrying such a booster in the car maybe moot because without 12 volt power you likely won't be able to get into the car at least not by electronic means you would probably have to find the manual levers to get the front open etc.

 

[Doanster1]

I thought brand wouldn’t matter either, but got unlucky with the Amazon special I purchased a couple years ago. When I actually needed it to help a stranded ICE car, it was dead. When I tried tried to charge it later that night, it literally smoked on me. After taking it apart before throwing it out (recycled), there were burn marks on the circuit board. Some component had given up the ghost.
Sprung for the unit from Schwaben (via ECS Tuning) and haven’t looked back, including helping another ICE car along with use as a USB battery bank.