Tesla Battery Investor Day

[ZeApelido]

Is it possible the limiting factor is the ability to keep the battery cool? At which point the lowered resistance would help?

Yeah I thought the main problem always was you could charge a battery at a higher C rate, but the heat would damage the battery.

If my assumptions are correct :

Heat is proportional to current squared and resistance linearly. If you halve the resistance, current could go up 40% with same heating.

If you reduced resistance 9x, current could go up 300%. That's 3x faster recharging, like 0 to 80% in 6 minutes...

 

[Doggydogworld]

Is it possible the limiting factor is the ability to keep the battery cool?

Perhaps, but I can't see foil substrates playing a big role here. The active materials are always the issue. That's why Tesla tapers so aggressively. It's the active materials that change properties as SOC increases, the foils couldn't care less. If foil heat was the limiting factor you could Supercharge at 250 kW for a few minutes whether your starting SOC was 10% or 70%.

Also, if foil heat were the limiting factor, why pre-heat the battery before Supercharging? That would only make the problem worse. Again, it's all about the active materials, which need high temperature for fastest ion transport.

 

[transpondster]

anyone care to check my numbers: Google Sheets - create and edit spreadsheets online, for free.
I calculate high internal resistance power loss at high power


Resistivity at 20 C (nΩ m) 26,50
Temperature coefficient 0,00390
Temperature (Celsius) 40,00
Resistivity (nΩ m) 28,57
Thickness (um) 16,00
Width (mm) 64,00
Current (A) 15
Length (cm) 84
Resistence of 1 cm (did u expected integrals?...) 0,000279


Total resistive power (W): 1,789049225

of course I don't know thickness of foil in Tesla's cells, but if there are no mistakes in my numbers resistive loses just in foil are high at high power and no way in hell they would be able to make bigger cylindrical cells

 

[Buckminster]

From main thread:

This could be massive if true, highly recommend reading the entire article:
Exclusive: Tesla's secret batteries aim to rework the math for electric cars and the grid - Reuters

Key sections:

• "Tesla Inc plans to introduce a new low-cost, long-life battery in its Model 3 sedan in China later this year or early next that it expects will bring the cost of electric vehicles in line with gasoline models, and allow EV batteries to have second and third lives in the electric power grid."
• "Tesla’s goal is to achieve the status of a power company, competing with such traditional energy providers, sources said."
• New "million mile" Battery to be a joint development between Tesla and CATL, significant technology contributions from Tesla
• Improved versions of this battery (better density, lower cost) will eventually be rolled out internationally
• "Tesla’s plan to launch the new battery first in China and its broader strategy to reposition the company have not previously been reported. Tesla declined to comment."
• "Tesla also plans to implement new high-speed, heavily automated battery manufacturing processes designed to reduce labor costs and increase production in massive “terafactories” about 30 times the size of the company’s sprawling Nevada “gigafactory”"
• Tesla to be working on battery recycling and second life applications, plans to become electric utility
• "CATL also has developed a simpler and less expensive way of packaging battery cells, called cell-to-pack, that eliminates the middle step of bundling cells. Tesla is expected to use the technology to help reduce battery weight and cost."
• "The cost of CATL’s cobalt-free lithium iron phosphate battery packs has fallen below $80 per kilowatt-hour, with the cost of the battery cells dropping below $60/kWh, the sources said. " (keep in mind that LFP chemistrys only work for lower range EVs, ie the SR+ M3, due to their low energy density of ~160 Wh/kg. The LFP discussion is pretty much independent of the new cell tech, and mainly a way on increasing margins on the chines SR+ as far as I can tell)

 

[mrbulk]

From main thread:

I read the article. One of several about this already actually. And I am happy and excited about this since I still have an S on lease until next year and then a CT on order. Hopefully this batt tech will be in all new Tesla's (and not just China) by then.

My only concern though - might this not create an Osbourne Effect for Tesla? Anyone contemplating a/nother Tesla yet not pressed to pull the trigger for some urgent reason at the time, would most certainly wait for additional news about this development.

 

[MC3OZ]

I read the article. One of several about this already actually. And I am happy and excited about this since I still have an S on lease until next year and then a CT on order. Hopefully this batt tech will be in all new Tesla's (and not just China) by then.

My only concern though - might this not create an Osbourne Effect for Tesla? Anyone contemplating a/nother Tesla yet not pressed to pull the trigger for some urgent reason at the time, would most certainly wait for additional news about this development.

My hunch the new battery is only initially available in higher priced Plaid Model S/X, then Cybertruck form day 1.
IN other cars they will try to keep any upgrade secret until it is in production..
Constantly improving products and making the best products is more important than worrying about the Osbourne Effect, it may happen occasionally, but it is hard to totally avoid.

 

[MC3OZ]

https://twitter.com/carsonight/status/1270722153898315795

I know a young man who works at Panasonic and he's ready to quit. He is sick and tired of being sick and tired, of being one of 3 or 3 on a line where there should be 7. He tells of 75 being hired and only 40 bother to show up on the first day of work,

I posted this tweet because it raises an interesting question:-

"Will Tesla Roadrunner packs need fewer working per kWh of pack production?"

It is an interesting question because "Yes" is the likely answer and a smaller workforce per kWh of production would be a significant saving..

Why I'm optimistic is the Semi packs will be product at GF Nevada, Tesla would not do that if getting sufficient battery line workers was an issue..

 

[Buckminster]

Delayed to 15th September most likely. Will be held in Fremont and include a tour of the battery manufacturing line.

 

[mrbulk]

Delayed to 15th September most likely. Will be held in Fremont and include a tour of the battery manufacturing line.

I just hope this does not suppress sales to those still on the fence...for myself not a huge problem as my CT will not be built until long after that and I have the S to drive meanwhile.

 

[MC3OZ]

I just hope this does not suppress sales to those still on the fence...for myself not a huge problem as my CT will not be built until long after that and I have the S to drive meanwhile.

Tesla can announce that the new batteries are going into some vehicles, Plaid Model S and Semi and make Plaid Model S available to order. Very likely that Plaid Model S costs more than a regular Model S...

That would stop some of the speculation, if Tesla was able to do it..

My guess is so far order rates are still good, the speculation is unlikely to have a major impact on Q3 sales.
As per Q2, China is picking up some of the slack...

 

[mrbulk]

I am hoping in September Elon not only announces this “battery breakthrough”, but that all cars made since back in xxx now already come with them!

We can hope ...

Tesla's Battery Day, September 15, Could Announce New EV Battery Tech

 

[JRP3]

I think the hackers would find out that information ahead of time if Tesla were hiding excess capacity. If battery day is nothing more than increased longevity that would be a major fail. I expect whatever is announced to show up in future vehicles, maybe Plaid S first.

 

[MC3OZ]

I think the hackers would find out that information ahead of time if Tesla were hiding excess capacity. If battery day is nothing more than increased longevity that would be a major fail. I expect whatever is announced to show up in future vehicles, maybe Plaid S first.

It is worth linking the Roadrunner project which we discussed in the main thread yesterday:-
Tesla reveals more on status of Roadrunner secret project for battery production - Electrek

Most probably these cells are going into Plaid Model S... perhaps all Model S/X, perhaps even some Model Y..

This ties in with the re-openning of the South paint shop and possibly GA5:-
Application 30204: Fremont South Paint Shop Modification Project (PDF) : teslamotors

So my expectation is:-

• More longevity
• Higher margins
• Higher production volumes.
• Quicker scaling of additional capacity with lower capex, a much smaller footprint and lower energy consumption...

That is a high bar, but it has to be "mind blowing"

I think conventional 2170 may get chemistry improvements more more longevity...

Roadrunner cells are more likely in the higher end high margin cars, 2170 cells are more likely in the base models.

 

[JRP3]

Still cobalt based cells and only an application for construction approval. I don't find it likely that any cells from this would make it into products this year.

 

[MC3OZ]

Still cobalt based cells and only an application for construction approval. I don't find it likely that any cells from this would make it into products this year.

The pilot line and R&D is a separate facility..

I don't think they need 400 workers, 4 x 100 per shift and 24 x 7 operation and 38 trucks per day, if they are merely testing a pilot line.

The construction approval was lodged in March with a 3 month long project,

Perhaps they start in Mid-April and construction is complete by the end of July..or earlier.

 

[MC3OZ]

Will Tesla get into mining and chemical processing?
After watching all of the videos below this seems like a possibility.

And announcing they are doing it is possibly more important than doing it, miners and processors need firm orders to justify investment in projects that will be up and running in 5-7 years time..
A stable market with long term contracts at reasonable prices benefits everyone, to get that battery makers and car makers need to commit.

 

[Buckminster]

From the main thread:

In response to twitter question about lithium supply..........

Elon Musk
@elonmusk

Replying to
@bipulh
All questions will be answered on Battery Day, Sept 15th. Will be webcast, although there is much to see in person.
4:38 PM · Jul 1, 2020·Twitter for iPhone

This was in response to "what happens when all the Lithium has been used up". Suggests Tesla will either:

1. Reduce amount of Li per battery
2. Get into mining
3. Extract Li from the sea

2.5 months to find out.

 

[mongo]

From the main thread:

This was in response to "what happens when all the Lithium has been used up". Suggests Tesla will either:

1. Reduce amount of Li per battery
2. Get into mining
3. Extract Li from the sea

2.5 months to find out.

If all the lithium is used up, it's time for a new planet...

The total lithium content of seawater is very large and is estimated as 230 billion tonnes,

At 20 mg lithium per kg of Earth's crust,[53] lithium is the 25th most abundant element.

Lithium - Wikipedia

 

[MC3OZ]

From the main thread:

This was in response to "what happens when all the Lithium has been used up". Suggests Tesla will either:

1. Reduce amount of Li per battery
2. Get into mining
3. Extract Li from the sea

2.5 months to find out.

I'm expecting Battery Day will include some information on how Tesla will source raw materials for battery production*, and probably also information on recycling..

* This may include getting into mining..

 

[MC3OZ]

Interesting video, but I've never seen conclusive proof that Tesla did acquire SilIon.

Not long to wait folks...