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Is the new Model 3 already at 48V or still at 12V for board electronics

Is the new Model 3 already at 48V or still at 12V for board electronics

It would be an advantage to wire sizes and efficiency to have a higher voltage.
As automotive is moving for mild hybrids now to 48V, several products with higher power demand should be available.
Heater/AC for example.

JeffreyR | 21 maggio 2017

Elon said during today’s Q1 earnings call that the Model Y would be on a different platform than the Model 3. The original intent was to have the Model Y on the Model 3's platform. But they are talking about going from a 3-km wiring harness in Model X to a 100-m harness in Model Y.
"Tesla Model Y arriving in late 2019 or 2020 on non-Model 3 platform"
http://www.teslarati.com/tesla-model-y-2019-2020-non-model-3-platform/

The hope is that the lessons learned from the Model 3 and a new approach to in-car tech, like forgoing the 12V battery, will enable the Model Y to be manufactured in faster and easier than the Model 3.

danielebernd | 21 maggio 2017

I wonder if model 3 has the oldfashioned lead acid battery for the 12 V board electronics or a modern lithium battery...
That would be much more efficient and vampire drain while parked unplugged would be much smaller...
Nobody knows..... :)

TeslaTap.com | 21 maggio 2017

@ cb500r - On the Model S and X, the heater and A/C compressor are already running off the 350/400v high voltage, which is more efficient than 48v and uses smaller cables. No need to go backwards to 48v!

For low power electronics, the cost/cabling difference between 12v and 48v is negligible. System for 48v like the wiper motor or rear window defroster could benefit from a 48v system, but it does limit suppliers - so costs could go up for a while.

Using a low wire-count harness is much more about distributed processing than voltages. Rather than send 12 wires to headlight module from the ECU to light all the different portions, using a CPU in the headlight could reduce it to 1 or 2 signal wires and power. A lot of this is already done, but far more can be done in this area. Most new car generations are going this route.

TeslaTap.com | 21 maggio 2017

@danielebernd - I doubt Tesla is going with a Lithium-Ion 12v. It is really poorly suited to this application due to cost, thermal issues and lifetime problems. The deep discharge battery Tesla uses in the Model S is a better solution.

It's becoming standard that 12v batteries are not lasting as long as they used to in all cars (EVs and ICE). The huge amount of additional electronics, some of which remains on all the time, causes more cycling of the 12v battery. Perhaps the electronics will get better (i.e. lower power), but it's hard to reduce the power for transmitters (i.e. celular, fob communications, wifi, etc.) that may occur even when the vehicle is off for related features.

carlk | 21 maggio 2017

Tesla does need the cold cranking power like ICE cars do. Its battery requirement is very different from others. Even ~4V is sufficient to run the CPU and electronics. Not sure what are requirements for those motors that run AC, brakes, etc though.

TeslaTap I remember Porsche has offered lithium 12V battery which was a $2K or $3K option.

danielebernd | 21 maggio 2017

@teslatap: Wouldn't It be better if there was a switch in the model 3 to have all electronics off if the car is parked unplugged. I mean It is not really necessary to have Remote access to the car and over-the-air updates all the time. When the car is parked 3 weeks at an airport I would like to forget It for this time and not have to concern about.

Red Sage ca us | 21 maggio 2017

danielebernd: Such 'switches' are activated through software. You can put the car in a sort of 'Deep Sleep' mode if you like. It wouldn't be too much of a big deal over three weeks. Here, check this video...

[ YouTube -- JEPBkjmS2uE ]

danielebernd | 21 maggio 2017

Red Sage ca us: "deep sleep Mode" is good, but why not simply shut off the vehicle completely, disconnect everything? Simple and efficient. Am I really that stupid or why isn' t that possible?

kaffine | 21 maggio 2017

You want the Battery Management System to stay operational. That is likely the largest load while parked unless cabin temp control is active.

Other than that I would still want the alarm working and be able to track it if it was stolen so I would like the cell and GPS systems online as well.

I am surprised they don't eliminate the 12V battery and go with dc-dc power supplies that step the HV down to the 12V needed. Use a small one for the electronics that runs constantly and then another larger one for the more power hungry items that is only powered up when the car is in use. I'm guessing they have a reason that the battery is required and or better.

Red Sage ca us | 21 maggio 2017

danielebernd: kaffine is correct.

You don't want to brick your battery pack. That would be bad. Not quite as bad as every molecule in your body exploding at the speed of light. But pretty bad.

Tesla has a very smart battery management system and it will keep your battery pack healthy if you allow it to. And Tesla doesn't allow you to turn that system off, because they want you to have a healthy battery pack for as long as possible. See how that works?

Only the absolute essentials will be in operation during deep sleep mode. That is a good thing.

The real question is... Why does SONY use buttons labeled 'MODE EXECUTE STANDBY' instead of a simple ON/OFF switch on their electronic equipment?

jkilch | 21 maggio 2017

Very entertaining. Tesla will finally get it right with the Y.

jkilch | 21 maggio 2017

Cb500r you are correct.

ColoDriver | 22 maggio 2017

Red,

Perhaps the Vogons have been designing Sony gear?

ir | 22 maggio 2017

All Your Bases Are Belong To Us
MODE EXECUTE STANDBY
For Great Justice

Red Sage ca us | 22 maggio 2017

ColoDriver: +42! That's IT!!! I kept wondering why it was that I was so disturbed by people continually claiming that Tesla needed to 'up their game' to be 'more luxurious' with their interior designs in order to 'sell more cars' and stuff. Now I understand. It is because to me the sort of trappings of 'luxury' that so many claim to crave are as offensive as a Vogon's sensibilities of design treatments. Yuck.

"A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools." -- 'The Hitchhikers Guide to the Galaxy', Douglas Adams

Red Sage ca us | 22 maggio 2017

ir: I love it when a plan comes together.

"I hate warriors, too narrow-minded. I'll tell you what I do like though: a killer, a dyed-in-the-wool killer. Cold blooded, clean, methodical and thorough. Now a real killer, when he picked up the ZF-1, would've immediately asked about the little red button on the bottom of the gun." -- Gary Oldman as Jean-Baptiste Emanuel Zorg, 'The Fifth Element' (1997)

Garyeop | 22 maggio 2017

@Red Sage +84. (42 twice). Love the quotes.

topher | 23 maggio 2017

"I am surprised they don't eliminate the 12V battery and go with dc-dc power supplies that step the HV down to the 12V needed."

From understanding of a Prius, one of the things that battery does is close the relays that connect high voltage battery to the rest of the systems. This is a safety feature. Most of the time, when the car is on, that is exactly what they do. I expect Tesla does the same for the same reasons.

Thank you kindly.