ALL CyberTruck discussion

[Cosmacelf]

I thought the Tesla lithium ion battery had a coolant loop in it. I’ll have to go back and check out the Weber audio video about it.

Well looks like I’m wrong. Wouldn’t be the first time. No coolant loop. Weber did say something interesting though, he said the four cells were pouch cells. So completely different from any cylindrical cell. Obviously a temperature tolerant chemistry as well. Now I really want to know more about the CT LV battery.

 

[mongo]

We don't know if the CT's LV battery is separate or not, right?

Nope, all speculation on my part.

 

[jerry33]

Well, Tesla currently packages the LV battery separately, even routing cooling into it and everything. As to why, probably historical? IF Tesla's LV lithium ion battery can be as reliable as the pack (and they are testing that idea out in current cars), then there's no reason not to integrate it since replaceability would be the major reason. We don't know if the CT's LV battery is separate or not, right?



So the answer is that they just didn't do the hard work of designing their pack to allow for it? The DC-DC converter also adds cost, volume and mass and it sucks in comparison.

Isn't it part of the battery management system for the LV battery? Also having a separate LV battery means that the power steering and brakes will work should the main pack shut down. The first Roadsters did not have an LV battery, but that was soon changed.

 

[BioSehnsucht]

The LV battery is almost certainly lithium iron phosphate, rather than typical lithium NCA/NMC/etc you'd expect in a high performance Tesla HV battery, since reliability in a wide temperature range, especially without active thermal management, is more important than charge and discharge speed for that purpose.

 

[mongo]

The LV battery is almost certainly lithium iron phosphate, rather than typical lithium NCA/NMC/etc you'd expect in a high performance Tesla HV battery, since reliability in a wide temperature range, especially without active thermal management, is more important than charge and discharge speed for that purpose.

Maybe, but there is a lot more power draw on Cybertruck and they could leverage pack thermal management for it. LFP don't like to charge in below freezing temperatures.

 

[mongo]

Drew talking about Powershare needing either a Powerwall or special Gateway with auto transformer to deal with split neutral because neutral doesn't connect to the UWC/vehicle and car only outputs 240V.

https://twitter.com/x/status/1731184984105558136

 

[Cosmacelf]

All in one spot. Drew Baglino:

The challenge with vehicle to home backup is that the car can only provide 240V line to line. This is because the charging standards (NACS and CCS both) don’t have the neutral wire in them. But homes in the US / Canada are wired with split-phase 240, which means current must flow on the neutral wire. To provide this current when off grid, you either need a Powerwall, or a new Powershare version of Tesla’s energy Gateway with an auto-transformer in it.

Additionally, for homes without a Powerwall, the Universal Wall Connector provides an interface for logic power from the car to the switch in the gateway to power the disconnect open during an outage.

If you have a powerwall nothing needs to change about your home wiring. Similar to how existing powerwall customers charge their cars during a power outage (https://tesla.com/support/energy/powerwall/mobile-app/vehicle-charging-during-power-outage), Powershare-capable vehicles support bi-directional powerflow (charging and discharging) in this situation.

Of course, you can’t find this “new Powershare version of Tesla’s energy Gateway with an auto-transformer in it” anywhere on Tesla’s website. Hopefully it’ll be added soon.

Drew implies above that if you have Powerwall, you don’t need the UWC.

Seems that the Powerwall or the Powershare version of the energy gateway communicates with the Cybertruck via Internet/WiFi to tell it to dump power back into the house after the Powerwall/gateway has flipped the Transfer Switch to disconnect the house from the grid. Or something like that. Personally, I would like some manual way of activating CT power backup as I’d want to turn off heavy loads like AC, pool pumps, etc. before running the house on 9.6 kW.

 

[Unclepaul]

Tesla mentioned that an upcoming version of their wall charger will be configured to handle bi-directional current.

 

[jebinc]

All in one spot. Drew Baglino:



Of course, you can’t find this “new Powershare version of Tesla’s energy Gateway with an auto-transformer in it” anywhere on Tesla’s website. Hopefully it’ll be added soon.

Drew implies above that if you have Powerwall, you don’t need the UWC? How the heck does that work?

Come on Tesla, we need information on how this works…

Typical

 

[Unclepaul]

Imagine that the CyberTruck low voltage battery will be a 48V system. This will be what will power all the accessories, steer by wire, lighting, sound system etc. All the previous 12V components will become 48V. This is a heavy lift for Tesla, and unappreciated by many. Eventually 48V will take over and EV and ICE accessory loads. Saving lots of weight and expense.

 

[kpanda17]

Well, Tesla currently packages the LV battery separately, even routing cooling into it and everything. As to why, probably historical? IF Tesla's LV lithium ion battery can be as reliable as the pack (and they are testing that idea out in current cars), then there's no reason not to integrate it since replaceability would be the major reason. We don't know if the CT's LV battery is separate or not, right?



So the answer is that they just didn't do the hard work of designing their pack to allow for it? The DC-DC converter also adds cost, volume and mass and it sucks in comparison.

My feeling is the gen 3a hybrid cell 4680 will add 10% range in 2024 and gen 3b dry cell will add another 10% in 2025:
2023 320 miles
2024 360 miles
2025 400 miles
Same effect on the extra pack
2023 130 miles total 470+ miles
2024 150 total 500+
2025 170 total 600+ miles
All approx

Will be amazing to see and vs the competition just reselling CATL and BYD battery tech

 

[jebinc]

Imagine that the CyberTruck low voltage battery will be a 48V system. This will be what will power all the accessories, steer by wire, lighting, sound system etc. All the previous 12V components will become 48V. This is a heavy lift for Tesla, and unappreciated by many. Eventually 48V will take over and EV and ICE accessory loads. Saving lots of weight and expense.

Definitely a cost savings/profit enhancer for Tesla. For customers, at least in the early days, it means costly, hard to find 48v accessories and adapters. The aftermarket will have an absolute field day and economic boom.

 

[Cosmacelf]

Definitely a cost savings/profit enhancer for Tesla. For customers, at least in the early days, it means costly, hard to find 48v accessories and adapters. The aftermarket will have an absolute field day and economic boom.

I expect the industry to move towards USB-C powered accessories. A lot of new cars have that available. You could expect to get 120W from a cigarette adapter. USB-C provides 100W, but extensions can provide up to 240W (at 48V!). Would be interesting to see if CT can output 48V from its USB-C connectors, But it will output for sure 20V at 5A at least since that’s the base spec.

 

[Cosmacelf]

Imagine that the CyberTruck low voltage battery will be a 48V system. This will be what will power all the accessories, steer by wire, lighting, sound system etc. All the previous 12V components will become 48V. This is a heavy lift for Tesla, and unappreciated by many. Eventually 48V will take over and EV and ICE accessory loads. Saving lots of weight and expense.

Yeah, Tesla somehow had to find/build 48V headlights, door window motors, latch releases, blower motors, seat heaters, ambient lights, etc. I really want to learn how they did it. I also wonder if Tesla has considered becoming a 48V parts supplier to the industry?

 

[Buckminster]

Tesla mentioned that an upcoming version of their wall charger will be configured to handle bi-directional current.

Universal wall connector already updated on website.

 

[mongo]

Yeah, Tesla somehow had to find/build 48V headlights, door window motors, latch releases, blower motors, seat heaters, ambient lights, etc. I really want to learn how they did it. I also wonder if Tesla has considered becoming a 48V parts supplier to the industry?

1. They technically don't need to because their control modules can put out 12V compatible power
2. Cybertruck was (I think) 85% in house modules. Gen 3 will be 100%
3. 48 Volt LED lighting can actually be easier than 12V to design circuits for

 

[Cosmacelf]

Yeah, Tesla somehow had to find/build 48V headlights, door window motors, latch releases, blower motors, seat heaters, ambient lights, etc. I really want to learn how they did it. I also wonder if Tesla has considered becoming a 48V parts supplier to the industry?

Actually Tesla had TWO huge under the hood changes. 48V low voltage wiring AND gigabit ethernet for comms (and I expect power delivery too since it supports Power Over Ethernet, at, guess what, 48V). Replacing CAN bus with Ethernet is just as huge a challenge. Now we are talking all cameras, radar, ALL sensors (like hundreds). CT really is the car platform for the future.

 

[mongo]

Actually Tesla had TWO huge under the hood changes. 48V low voltage wiring AND gigabit ethernet for comms (and I expect power delivery too since it supports Power Over Ethernet, at, guess what, 48V). Replacing CAN bus with Ethernet is just as huge a challenge. Now we are talking all cameras, radar, ALL sensors (like hundreds). CT really is the car platform for the future.

I'm thinking dual automotive Ethernet (one pair each) at Gigabit rates and separate power lines due to redundancy and power requirements.

Cameras may stay direct LVDS to HW4 due to bandwidth (and redundancy) requirements. Uncompressed (raw data) at 5 Megapixel, 30 frames per second, 8 cameras at 16 bits per pixel is 19.2 Gbps.
Radar (should it exist) may also retain a separate link.

In house ethernet is going to be easier to deal with than outsourced CAN (based on past experience).

 

[jerry33]

Actually Tesla had TWO huge under the hood changes. 48V low voltage wiring AND gigabit ethernet for comms (and I expect power delivery too since it supports Power Over Ethernet, at, guess what, 48V). Replacing CAN bus with Ethernet is just as huge a challenge. Now we are talking all cameras, radar, ALL sensors (like hundreds). CT really is the car platform for the future.

So will be be able to use our microphones requiring phantom power? For Karaoke if nothing else.

 

[Cosmacelf]

I'm thinking dual automotive Ethernet (one pair each) at Gigabit rates and separate power lines due to redundancy and power requirements.

You are almost certainly right. I'm betraying my non-automotive data comm roots. There are indeed single and dual pair copper ethernet standards for automotive use. As well as cheap plastic fiber optic Ethernet for automotive. In they used copper, they could also provide power over that too. The coolest implementation, I guess, would be fiber optic with separate power. Why would you think dual pair, why not just one pair if they used copper?

Cameras may stay direct LVDS to HW4 due to bandwidth (and redundancy) requirements. Uncompressed (raw data) at 5 Megapixel, 30 frames per second, 8 cameras at 16 bits per pixel is 19.2 Gbps.
Radar (should it exist) may also retain a separate link.

I had forgotten that the cameras sent raw uncompressed to the FSD board. Again, yes, they would stick with LVDS...

In house ethernet is going to be easier to deal with than outsourced CAN (based on past experience).

If they are building all their own modules, then yes, sure would be easier! Would be fascinating to read more about the data comms protocols that Tesla uses.