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12V battery going away

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Sir Guacamolaf

The good kind of fat
Mar 15, 2016
1,150
1,920
Not in a Tesla
Yeah yeah I know this is a Model S forum, but thought you might be interested in hearing this.

Model Y, SUV, based on Model 3 platform, coming in 2019.
And get this - it won't have a 12v battery. Elon says, this will save a significant amount of wiring, i.e. easier manufacturing process...

.. which tells me ... that we will most likely see similar architecture in S and X also.


YaY!

On a different note,
- SUV
- Smaller toad might actually look cute
- No 12v battery
- Cheaper
- Lets hope no funky doors

.. might be my next car.
 
Actually in today's quarterly earnings call he said the Model Y would be based on the Model 3 in order to get it to market faster.

Indeed:

Tesla earnings send stock higher amid Model 3 rollout: Live blog recap

Model Y will not a completely new architecture, will use substantial carryover from Model 3 to bring it to market faster, Musk says. That is correction from last quarter, when people assumed Tesla would be building new factory for Model Y.

Elon corrects his record about the Model Y compact SUV: It will bring “substantial” carryover from Model 3 so get the vehicle to market faster.

The fact that it will get rid of the 12V is not new news, however. It's really the only thing I've ever found interesting about the Y. The 12V system has outlived its welcome and deserves to be consigned to the dustbin of history. The amount Tesla is going to be simplifying and lightening the wiring harness in the Y is such a breath of fresh air from the reverse trend which has been weighing down the auto industry more and more every year.
 
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Question really is will they abandon 12V altogether or just eliminate the battery?

Nearly all traditional at accessories run on 12V (dash cams, radar detectors, phone chargers, etc).

I assume the car's electronics would run on something reasonable... maybe 48V DC stepped down from the main pck voltage of 400VDC (or, possibly, tapped off of a few "banks" of 24V... could even do it in such a way where the car's LV system is constantly switching the internal "packs" it draws from to keep the cells balanced.... or they just tap off two rails. A 24 or 48V rail from all (or half) the packs in parallel, and the 400V DC rail from all sub packs in series.

Could of course just step down from HV too, but you would presumably loose some efficiency.
 
Question really is will they abandon 12V altogether or just eliminate the battery?

Nearly all traditional at accessories run on 12V (dash cams, radar detectors, phone chargers, etc).

Altogether - and that's why it's a big deal and tough to do, because everything uses it at present, even though - as Elon put it - it's "not the right voltage for anything."

I assume the car's electronics would run on something reasonable... maybe 48V DC stepped down from the main pck voltage of 400VDC

Your guess is as good as any. But I know they're going to want it as high as possible in order to minimize wiring mass. The length of the wiring harness they're talking about is insanely short, too - 100m. Car wiring harnesses today are generally measured in miles / kilometers.
 
Yeah yeah I know this is a Model S forum, but thought you might be interested in hearing this.

Model Y, SUV, based on Model 3 platform, coming in 2019.
And get this - it won't have a 12v battery. Elon says, this will save a significant amount of wiring, i.e. easier manufacturing process...

.. which tells me ... that we will most likely see similar architecture in S and X also.


YaY!

On a different note,
- SUV
- Smaller toad might actually look cute
- No 12v battery
- Cheaper
- Lets hope no funky doors

.. might be my next car.
To me, the "funky" doors you talk about are the best things on the Model X.
 
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Altogether - and that's why it's a big deal and tough to do, because everything uses it at present, even though - as Elon put it - it's "not the right voltage for anything."



Your guess is as good as any. But I know they're going to want it as high as possible in order to minimize wiring mass. The length of the wiring harness they're talking about is insanely short, too - 100m. Car wiring harnesses today are generally measured in miles / kilometers.

Who knows, maybe they'll get all their 3rd party vendors to make 400V DC parts :p

Would likely make a few things more efficient (and reduce wire gauge needed for low power devices).

I just hope they put high powered USB ports in this time ;-)
 
The 12V battery may go away, but I dont think the 12V voltage will go away anytime soon. There is a lot of components in the car that are powered by 12V, like sensors, lights, electric motors in the seats, window regulators, airbags etc.
I believe switching to 48V will be too expensive for Tesla to do this effort alone, and they will probably have to wait until automotive suppliers can sell 48V components to several automakers.

BTW Audi has started to use 48V for some components in the recently launched A8.
 
The 12V battery may go away, but I dont think the 12V voltage will go away anytime soon. There is a lot of components in the car that are powered by 12V, like sensors, lights, electric motors in the seats, window regulators, airbags etc.
I believe switching to 48V will be too expensive for Tesla to do this effort alone, and they will probably have to wait until automotive suppliers can sell 48V components to several automakers.

BTW Audi has started to use 48V for some components in the recently launched A8.

What about a capacitor?
 
I don't think the plan ever involved removing the low voltage battery. I think the plan was to have a different low voltage - either the 42V the industry has been trying to move to for a couple decades or something else.
 
What about a capacitor?

I think that's a great idea.

Supcercapacitor is charged up very quickly but it can't hold a charge for long.

It is great for city buses because they run very a short distance and they have to stop at many stations to pick up riders.

By the time the riders are boarded, a supercapacitor could be fully charged.

supercapacitor-electric-bus.png


Using supercapacitor as a low voltage accessory battery is great because the main pack can recharge it instantaneously.

The problem is since it does not hold a charge very long, vampire rate for the main pack will be so large that making supercapacitor impractical.