Tesla Semi

[scaesare]

Soo.. do you have a source for that, or have you observed them first hand?

 

[mongo]

Soo.. do you have a source for that, or have you observed them first hand?

He likely saw them late in the evening at the end of September while visiting the factory. (And isn't allowed to admit it) (Referenced in post #1818)

 

[dhanson865]

This is essentially what I was suggesting in my last post.

Say you have 1MWh in the physical battery, but it is dynamically "unlocked" only to allow 500 physical miles. Perhaps in ideal conditions only 1.2 kWh/mile is needed. That is only 60% of the pack is needed. So the software knows to keep the SOC within 20% to 80%. The driver only sees and has access to the middle 60%. But suppose that under extreme conditions (weather and grade), 1.8 kWh/mile is needed. This unlock the middle 90% of the battery and the software holds SOC between 5% and 95%.

In all cases, the driver is limited to 500 physical miles but the fraction of the battery dynamically unlocked varies from about 60% to 90% of original 1MWh capacity. This could be why Tesla spoke of a 2kWh/mile upper bound. This may be sufficient for 99% of all driving conditions, but Tesla will want fairly strong control over depth of cycling to minimize abuse to the battery. Tesla can't put a 1 million mile warranty out there and allow drivers to abuse packs. They've got a software layer between the driver and the pack.

That's how Toyota did it on the Prius. The user has no control over the NiMH pack, car charges if needed, uses it if it is available. User has to keep gas in and deal with it.

Tesla doing similar but minus the gas engine makes a lot of sense once the batteries get cheap enough. I guess that is why the Model 3 is "Long range" or "Short range" instead of advertising capacity.

They can continue to increase the pack capacity any time the tech improves and keep the advertised range the same. Eventually when there is enough buffer they can change the advertised range on new vehicles and offer a software unlock on some of the old ones that have battery health high enough to allow it.

I could see this attitude with software abstraction of the battery capacity running from the Model 3, S, X, all the way to the semi. Could be the new normal for Teslas of all shapes and sizes.

 

[scaesare]

He likely saw them late in the evening at the end of September while visiting the factory. (And isn't allowed to admit it) (Referenced in post #1818)

Ah, I didn't have the context of a factory visit... thanks.

 

[Brando]

Careful not to confuse battery package vs chemistry.
2170 is the newest cell package for Li - Panasonic and Samsung - probably others - have to search

Elon and JB have both stated numerous times, that storage and auto have different duty cycles and therefore optimisation means different chemistries. (i.e. not the same chemistries.

 

[jhm]

Forgive me if it's this thread already... but I remember seeing discussion that the Semi battery chemistry may be similar to the PowerWall/Pack chemistry for cycle-life reasons. Was this stated by Elon... or was that just conjecture?

I have a vague recollection of that, but it would be good to locate specific language used. Often there is enough ambiguity in what Elon says that you can't fully nail this down. We know on the price side the Semi is not merely equivalent to 1MWh of Powerpacks, so what else is different?

 

[mongo]

I have a vague recollection of that, but it would be good to locate specific language used. Often there is enough ambiguity in what Elon says that you can't fully nail this down. We know on the price side the Semi is not merely equivalent to 1MWh of Powerpacks, so what else is different?

I do not recall this piece of data regarding chemistry from Elon.

More helpfully: a Powerpack contains 16 individual battery pods each with their own DC-DC charge/discharge control power units (3.3ish kW). The PP on a whole also contains the cooling system and the housing itself. So you can't use the 210kWh of AC power vs PP price as a straight benchmark.

 

[mongo]

I have a vague recollection of that, but it would be good to locate specific language used. Often there is enough ambiguity in what Elon says that you can't fully nail this down. We know on the price side the Semi is not merely equivalent to 1MWh of Powerpacks, so what else is different?

Other brain blip:
I believe I recall J.B. mentioning recently that due to the high energy figure, the power requirement was not a limiting factor. That might lend itself to the TE chemistry.

 

[Off Shore]

Other brain blip:
I believe I recall J.B. mentioning recently that due to the high energy figure, the power requirement was not a limiting factor. That might lend itself to the TE chemistry.

This article I linked upthread explicitly says the Semi will use NMC chemistry, though IRRC the author doesn't reference a source.

 

[mongo]

This article I linked upthread explicitly says the Semi will use NMC chemistry, though IRRC the author doesn't reference a source.

Article says the info came from Elon

Musk stated the battery pack uses the same cells as the Powerpack, which us NMC chemistry. Each Powerpack is 3,575 lbs and has 210 kWh of energy capacity.

 

[scaesare]

This article I linked upthread explicitly says the Semi will use NMC chemistry, though IRRC the author doesn't reference a source.

Ahhh thanks... that's where I remember seeing it:

"Musk stated the battery pack uses the same cells as the Powerpack, which us NMC chemistry."

He does cite Musk... but not where or when.

 

[BioSehnsucht]

Elon might have only stated they use the 2170 cells.. and Cleantechnica made their own leap of logic to NMC because of power pack, even though 2170 are also used for Model 3 with a different chemistry. Though I'd expect them to know better ... ?

 

[Reciprocity]

SEMI could use NMC. There is a new Chemistry called NMC 811 that many are migrating to, including the LG pack in the Ipace supposedly. The interesting thing is that its different from the cells that LG made for GM for the Bolt even though the format was identical. This would explain how Tesla is able to get a million miles from the pack with charge cycles of upwards of 5000. Its much closer in terms of energy density, while having greater durability and slightly higher recharge rates. Its also less Cobalt, so it would be cheaper then NCA.

 

[Sudre]

This was on the St. Louis Tesla Enthusiasts Facebook page today. Looks like AB might have wanted a peek at the Semi. Picking up a charger at the St. Charles supercharger.

Kyle Feller

 

[D-egg-O]

Some pictures of the semi that looks like it has some extra cameras. Sourced from electrek’s article.
A closer look at a Tesla Semi electric truck prototype and its electric motors

 

[BioSehnsucht]

second pic, looks like it has a camera down-and-back and also straight down, though that might be mounting hardware

third pic, I don't see a camera, looks like mounting hardware

 

[D-egg-O]

second pic, looks like it has a camera down-and-back and also straight down, though that might be mounting hardware

third pic, I don't see a camera, looks like mounting hardware

That was my thought too about the mounting hardware.

 

[gjunky]

having a camera above the hitch would make perfect sense.

 

[D-egg-O]

having a camera above the hitch would make perfect sense.

Yes. And my thought is the two circles above it are proximity sensors when backing up to a trailer. If those are proximity sensors then the ones on the sides are also possibly proximity sensors for the moveable flaps controlling the air gap to the trailer. Hard to tell 100%. Those could just be part of the mounting hardware as mentioned above.

 

[dc_h]

I think they will build the semi in Sparks with some parts made in Fremont, so there will be no deadhead.

They can send stamped parts back on empty battery trucks for the semi.