Investor Engineering Discussions

[MC3OZ]

Above ground city rail is in 2 categories:-

1. Main trunk lines for intercity high speed travel and freight.
2. Suburban mainly passenger lines.

For 1. Main Trunk Lines, it is best to leave them untouched, but eventually the real estate development opportunity may see these routed around the city and interfacing on the city fringe.

2. Suburban passenger Lines - if underground Boring Cop tunnels can transport the suburban passengers these represent a major Real Estate Development opportunity that can also enhance quality of life and provide good quality cycleways along those routes.

The big advantages of these lines is that they are lines, so if we build everything on the same level things like utilities can be routed easily and additional transport corridors can be provided via a "multi-level" approach.

This is one example:-

• B3 (basement 3) - West - Utilities, East - Batteries, rainwater tanks, storerooms, Boring Co access ramps where needed (opposite side to utilities)
• B2 -Parking/ storage.
• B1 - Parking.
• Ground Floor - Local access road/parking - follows approximate route of train line
• 1 -Pedestrian zone and cycleway. (some shops?)
• 2 - Shops
• 3- Offices
• 4-6 Residential
• Roof Top - outdoor recreation and sporting zone, with some cafes and swimming pools, gyms, badminton, basketball and indoor tennis courts, with a solar canopy. - (Privately owned, but residents and visitors can become members -, public walkway can't be closed

For levels B2, Ground, 1 and the Rooftop the space always flows through to the next space providing a transport corridor, this is the big advantage of a line.

For level 2 offices, the amount of flow through is dependent on the security requirements of those that own/rent the offices.

The challenge with a line is that is a long relatively thin space depending on how wide the train tracks are, but I am sure that good architects could make it work. Shops, offices and homes may need to have a long thin form factor, but that can mean more windows and natural light. Or perhaps in some areas the rail line may be too thin for sensible development to occur, so some parts might just be a transport/utilities corridor.

In some cases the road beside the rail line may be able to be incorporated into the development that widens the road and also increases the area for living space above the rail (area) + road. if ICE vehicles will use the road, ventilation needs to be considered. Hopefully this is far enough into the future for ICE vehicles to not be a major consideration.

 

[willow_hiller]

Is anyone familiar with FCC regulatory processes? I'm assuming there's nothing stopping Tesla from filing for a further extension of the confidentiality treatment they were granted for the radar device expiring on February 7th?

In their filing Tesla said there were plans to advertise the product containing the device in mid-January, but obviously those plans have been delayed. I'm just curious whether we can look forward to learning more about it in 5 days, or whether we'll just see another extension.

 

[mongo]

Is anyone familiar with FCC regulatory processes? I'm assuming there's nothing stopping Tesla from filing for a further extension of the confidentiality treatment they were granted for the radar device expiring on February 7th?

In their filing Tesla said there were plans to advertise the product containing the device in mid-January, but obviously those plans have been delayed. I'm just curious whether we can look forward to learning more about it in 5 days, or whether we'll just see another extension.

The documents are currently scheduled for release March 7th (one month later than the request).
I know of no reason it could not be delayed further.
OET List Exhibits Report

 

[Ogre]

The documents are currently scheduled for release March 7th (one month later than the request).
I know of no reason it could not be delayed further.
OET List Exhibits Report

This coming out 6 days after the investor meeting on March 1st makes a ton of sense.

My guess is this is a Cybertruck feature.

 

[mongo]

Heat pumps work better at a near constant temperature. If you are going to use a set back temp you want to ramp them up at a slower rate like 1 degree per hour (and use a smaller set back so that isn't an issue).

Don't turn it down so much on a daily basis, only use a severe setback for when you leave the house unattended for multiple days.

Constant temp or minimum thermal demand?
Wheras a gas furnace can be way oversized with a high output/ outlet temp, a heat pump will be sized closer to actual load, has a lower outlet temp, and will be slower to raise the habitable space temperature.
So you may need to plan for a slow ramp, but the unit doesn't care (unless two stage with different efficiencies).

5 ton 60k BTU heat pump: $4,500 with 45A/15A circuits.
96k BTU gas furnace: $2,100 with 15A circuit

 

[Cosmacelf]

The Limiting Factor‘s Jordan just tweeted this 6 month old video of how cylindrical battery cells are welded to bussbars.

 

[JRP3]

I'd think a pack sized unit with a welder for each cell that zaps all the connections at once would be the way to go, at least for the structural packs. Module sized units for modular packs.

 

[Oil4AsphaultOnly]

I'd think a pack sized unit with a welder for each cell that zaps all the connections at once would be the way to go, at least for the structural packs. Module sized units for modular packs.

Laser welders aren't cheap enough to have hundreds of simultaneous heads. And at 1kw per welder, that's A LOT of heat. This automated welder (doing both the positive AND negative connectors at once seems pretty ideal.

 

[Cosmacelf]

Laser welders aren't cheap enough to have hundreds of simultaneous heads. And at 1kw per welder, that's A LOT of heat. This automated welder (doing both the positive AND negative connectors at once seems pretty ideal.

So now I wonder if Tesla buys machines like this from a supplier, or whether they made their own laser welder, since they’ve been using packs like this for 15 years.

 

[Oil4AsphaultOnly]

So now I wonder if Tesla buys machines like this from a supplier, or whether they made their own laser welder, since they’ve been using packs like this for 15 years.

Multiple stations to make multiple packs simultaneously? That way your generated heat isn't localized to a single station and you can still average out one pack every minute. Plus redundant stations mean less down time for maintenance.

 

[mongo]

By the link you reposted, there is 160 grams of elemental Li per kWh in a pack.
75 Kwh * 0.16 Kg Li per kWh = 12 Kg

yah
My calc was the 100% utilization value (absolute floor) which the link applies a 2x factor to.
On the Q1 2022 call, Elon & Zach brought up the 5kg number, 2-3% of cell. So my original calc was a validity check on that number.

1 Li ion per electron
5,000 g * (6.02*10^23) / 6.941 / (6.28*10^18) / 60 / 60 = 19,181 Ah * nominal cell voltage
If cell is 3.7V: 19,181*3.7 = 71kWh
3.9V: 75kWh

 

[MC3OZ]

Anyone have a theory on why the front and rear of Highland Model 3s are currently covered?

My theories, which are not mutually exclusive.

1. All cars now have a standard front an rear bumper with is a common color
2. The rear trunk lid may be morphed to be more like a hatch, if this is more functional, and / or makes building the car easier and faster.

I am more confident about the bumper prediction, especially for cars intended to be cheaper and mass market, it simplifies manufacture and repair and may allow more car colors.

For the bumper, I would try black plastic with some stainless steel highlights, the idea is that the bumper is more scratch/dent resistant and minor scrapes will not result in it needing to be replaced.

 

[JRP3]

Trunk seems to end at the exact same place as current Model 3s so I don't see any evidence of a hatch.

Your bumper idea has some merit but if going for low cost and durability I wouldn't add any sort of accents. More parts = more cost, extra assembly steps, more inventory and more failure points.

 

[navguy12]

Anyone have a theory on why the front and rear of Highland Model 3s are currently covered?

My theories, which are not mutually exclusive.

1. All cars now have a standard front an rear bumper with is a common color
2. The rear trunk lid may be morphed to be more like a hatch, if this is more functional, and / or makes building the car easier and faster.

I am more confident about the bumper prediction, especially for cars intended to be cheaper and mass market, it simplifies manufacture and repair and may allow more car colors.

For the bumper, I would try black plastic with some stainless steel highlights, the idea is that the bumper is more scratch/dent resistant and minor scrapes will not result in it needing to be replaced.

I’m an outlier here, but if anything is being hidden it is the single castings being used for the front and rear chassis as per the modern Model Y.

 

[JRP3]

How would those hide the castings which are already hidden by body panels?

 

[mongo]

Any reason the battery pack couldn't be as long as the distance from front axle line to rear axle line? Full width under the passenger areas, narrowing at front and rear, and still a structural member mounted between the castings like on the Y, but built further into the front and rear castings. Would that be enough room to solve for 500 miles worth of batteries without double-stacking?

Extending beyond the axle lines could create potential issues with polar moment.

Drive units are in the way. It would alao reduce the pack protection.

 

[navguy12]

How would those hide the castings which are already hidden by body panels?

Good point.

An astute observer “could” discern the castings versus non-castings situation by looking at the openings of the wheel well liners, where the suspension (struts) tie into the unibody system…but that would require the depicted black cloth covers to continue up inside the wheel wells, which is highly unlikely.

 

[MC3OZ]

https://twitter.com/x/status/1622765104885374976

US10461319B2 - Elemental metal and carbon mixtures for energy storage devices - Google Patents

An energy storage device can include a first electrode, a second electrode and a separator between the first electrode and the second electrode wherein the first electrode or the second electrode includes elemental lithium metal and carbon particles. A method for fabricating an energy storage...

patents.google.com

Seems like it would take some time to wade though all this and work out what it means, but the Jordan rates it...

If you guys can get this working, it'll be

 

[JRP3]

This was discussed in 2021, lol.

Tesla, TSLA & the Investment World: the Perpetual Investors' Roundtable

Bullish. If you're going to build factories on Mars, you've got to optimise everything involved in the production process. Energy, volume, weight, materials, waste, speed, low staff. Those are the targets Elon needs to get close to, might as well trial, iterate, improve on Earth. How does a...

teslamotorsclub.com

Doesn't look like Flash to me. Part of it could be for monitoring the materials process, but those there look like parts. And you know what they say...

Parts is parts, just like grease is grease!

This image of the press mold makes me think the arrows above are pointing to partially filled overflow channels

https://pbs.twimg.com/media/FoUIUQGXgAokazd?format=jpg&name=large

 

[MC3OZ]

Seems like it would take some time to wade though all this and work out what it means, but the Jordan rates it...

It seems to be for a Lithium Metal Battery - Lithium Metal cathode - carbon Anode, but not just for Lithium:-

Energy storage devices, such as lithium ion, sodium ion, potassium ion, magnesium ion and/or aluminum ion based energy storage devices, may be used to power a diverse range of electronic devices. For example, batteries and/or capacitors using these materials can be implemented in a variety of applications,

It describes a method of making the battery without the drawings, I'll have stab at what it is talking about, but I could be wrong, and treat this as a ballpark guess only.

The anode is carbon but mixed with some lithium via a DBE like process and connected to a film and current collector, this is then exposed to carbonate liquid or vapour to build and the SEI layer.

I guess we could say that the anode is fabricated in a charged/semi-charged state?

The cathode can be:- ( I am an not sure if these are cathode shapes, or merely how the raw material can be provided)

Bulk elemental lithium metal can be provided in elemental lithium metal sheets, bars, rods, or other forms. In some embodiments, bulk elemental lithium metal can be one or more elemental lithium metal pieces each having a volume greater than about 1 cubic millimeter (mm3), including about 1 mm3 to about 1 cubic meter (m3). In some embodiments, bulk elemental lithium metal can refer to elemental lithium metal sheets having a thickness of about 5 microns (μm) to about 100 μm, including about 10 μm to about 80 μm, or about 50 μm to about 100 μm. Bulk elemental lithium metal can also refer to lithium chunks of various shapes.

The patent also covers process for making the battery.

In some embodiments, further includes providing bulk elemental lithium metal, and reducing a size of the bulk elemental lithium metal to form a plurality of elemental lithium metal particles.

Without wishing to be limited by theory, it is thought that lithium metal included in an electrode film may undergo redox processes to create free metal ions. Thus, an electrode including an elemental metal as provided herein, when in contact with an electrolyte, may release an electron and subsequently form a metal cation per lithium metal atom. The released metal ions may diffuse to either electrode.

In some embodiments, the energy storage device 100 can be a lithium based battery, such as a lithium ion battery. In some embodiments, the energy storage device 100 can be a lithium based capacitor, such as a lithium ion capacitor. Of course, it should be realized that other energy storage devices are within the scope of the invention, and can include capacitor-battery hybrids, and/or fuel cells.

What they have tested so far appears to be a coin cell,

It is a very board patent and very hard to understand, if I have got anything wrong, please let me know.

I'm aware of an aluminum ion battery made by an Australian company GMC, they uses specially engineered Graphene which is chemically etched to make holes for the aluminum ions. In this case, having the metal present in the carbon on formation makes holes, I think a lot of that metal reacted to make the SEI, somehow I guess the rest of it turn into ions? That part isn't very clear.

I guess that we can safely say that Tesla is just a car company