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Tesla, TSLA & the Investment World: the Perpetual Investors' Roundtable
- Thread starter AudubonB
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There’s also a blog post about it now from Tesmanian. Tesla China does seem to haphazardly leak info more often than US
Tesla Battery Day May Introduce Next-Gen Cobalt Free Non-LFP Cell Hints China
Today is brought to you by the number 900...
Yes, but you're using facts here. @Remus already decided he hates the idea, so he won't accept any counter-argument until Battery Day (or earlier, if the new battery pack for the Made-in-China Model 3 Standard Range* is introduced soon), when Tesla either doesn't reveal a LiFePO battery, or it does, in which case he will either sell all his TSLA holdings and say buh-bye to us all, or he will fully get behind the move and pretend nothing happened.
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electrichapp
Member
I hope Tesla is getting some compensation for that.
Wtf they don’t ship to the Netherlands
There's no question that iron phosphate is cheap. We'll just throw out all issues of manufacturing and focus just on raw materials. The problem is that it has terrible energy density. Halve the energy density and you double the mass of cells you need. Including on the anode end, which has nothing to do with the choice of iron phosphate vs. Nickel+Al/Mn oxides. Furthermore, even if you want to pretend that there's no inactive lithium among that, the lower voltage means you need more active lithium per Wh.
(And it's not like Ni+Al/Mn oxides are that expensive regardless, once you get rid of the cobalt)
Then comes C rates. Let's examine a simplified case without taper. Take a pack that contains 500kg of cells. Halve the energy density of the cells but stay at 500kg worth of cells (e.g. use half as many cells). Double the C rate. How does the rate you can charge, expressed in kWh per minute, change? Answer: it doesn't. It takes twice as long to charge to a full pack, but a full pack is twice as many kWh.
(The above gets worse for the low density / high C-rate cells when you factor in taper, since the low-density pack is doing a 0-100% cycle over a kWh range that the high-density pack is doing a 0-50% cycle)
That said, LFP is passively safer, sure. But so is nickel-iron, but I don't suggest that it's the future of EV chemistries either
(We're of course ignoring all issues of making cars heavier for a given amount of range, when Tesla has been pushing hard on dramatically increasing ranges and having better-than-ICE handling)
LFP is not the future.
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So dead ass heavy iron battery, high building cost for prismatic cells are not fact in your mind?
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Third Row is not the source. Here's the first tweet on the subject
Vincent on Twitter
Which is this article:
Tesla Battery Day May Introduce Next-Gen Cobalt Free Non-LFP Cell Hints China
Which cites this from Tesla China:
If you don't want to trust Vincent's translation, you can use Google Translate
Causalien
Prime 8 ball Oracle
But without proper ID, he could be one of the insiders who know about the bankruptcy and thus came to several forums to pump the stock. As far as I can tell, nobody knows the identity of the people who formed that GTAT forum.
*Batteries and broken glass window stickers not included
Krugerrand
Meow
Free advertising is priceless.
I really don't want to get involved into the whole "are LiFePO batteries the right answer for Tesla in China?" because I have reservations either way.
What I DO know is that one of Tesla's main areas of expertise is Li-ion batteries. Which means I'm convinced Tesla will not put off-the-shelf battery cells in cars unless they have a very compelling reason to do so AND the performance of the car (charge rate, discharge rate / power, range, and longevity / no. of cycles) meets their high standards. Or modify those cells so that their high standards are met and the cells fit well in the M3 battery pack.
So I'm preparing myself to be pleasantly surprised, rather than accept the foregone conclusion that it's a bad idea without actually knowing what it is they're planning to do.
Except for my Twizy. I've chosen LiFePO4 for a DIY battery project because of ~ 10 times higher number of cycles compared to LCO / NMC and a low total cost of ownership, very good long-term properties with low maintenance requirements and a high degree of investment protection and functional safety. But I've just started ... maybe I'll report in a few years
Krugerrand
Meow
I appreciate them trying to get it right, but if they soon don’t stop I’ll run out of ways to spend the money.
No doubt about it. No brand would let another use their IP for free. Hot wheels is going to sell these like hotcakes, to people like me who never wanted a fancy RC car until now.
Any issues with the departure of Mr. Kassekert? Unlikely if I had to guess, given their track record so far with Nevada, the learning experience and achievement of Shaghai, and the already-in-place plans for Berlin. Cruise control for this stuff now even without him ... and surely he'll have the position filled shortly:
Tesla loses one of its most senior executives and Gigafactory builder
Tesla loses one of its most senior executives and Gigafactory builder
Except for my Twizy. I've chosen LiFePO4 for a DIY battery project because of ~ 10 times higher number of cycles compared to LCO / NMC and a low total cost of ownership, very good long-term properties with low maintenance requirements and a high degree of investment protection and functional safety. But I've just started ... maybe I'll report in a few years
I actually don't disagree
For amateur projects, I'd recommend LFP, if you're not working with premade modules. NCA/NMC has to be babied more to ensure safety and longevity. There's a balance between "ease of use" and "optimal properties" 
Rashomon
Member
There's no question that iron phosphate is cheap. We'll just throw out all issues of manufacturing and focus just on raw materials. The problem is that it has terrible energy density. Halve the energy density and you double the mass of cells you need. Including on the anode end, which has nothing to do with the choice of iron phosphate vs. nickel+Al/Mn oxides. Furthermore, even if you want to pretend that there's no inactive lithium among that, the lower voltage means you need more active lithium per Wh.
Then comes C rates. Let's examine a simplified case without taper. Take a pack that contains 500kg of cells. Halve the energy density of the cells but stay at 500kg worth of cells (e.g. use half as many cells). Double the C rate. How does the rate you can charge, expressed in kWh per minute, change? Answer: it doesn't. It takes twice as long to charge to a full pack, but a full pack is twice as many kWh.
(The above gets worse for the low density / high C-rate cells when you factor in taper, since the low-density pack is doing a 0-100% cycle over a kWh range that the high-density pack is doing a 0-50% cycle)
That said, LFP is passively safer, sure. But so is nickel-iron, but I don't suggest that it's the future of EV chemistries either
(We're of course ignoring all issues of making cars heavier for a given amount of range, when Tesla has been pushing hard on dramatically increasing ranges and having better-than-ICE handling)
LFP is not the future.
Agreed. I designed the first LFP starter battery to be used as standard in a production ICE motor vehicle more than a decade ago. It weighed 25 percent of the high-performance lead-acid alternative -- even though lead-acid is surprisingly good in power applications. LFP has many advantages in high-power applications over other li-ion formulations, and while the materials are cheap, it's often not cheaper on an energy basis, particularly at the pack level. The rumored CATL deal is about what's available in the Chinese supply chain because Tesla soon has to stop importing packs to comply with various Chinese requirements -- if the CATL deal is actually happening. But LFP is always lower energy density than the best NCA or NCM cells, and much, much lower density than the high-silicon, cobalt-free cell than Tesla is hinting will be announced in April . . .
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