drdabbles

joined 1 year ago
[–] drdabbles@lemmy.world 1 points 3 weeks ago

LFP in Marine applications is mostly a cost driven choice, because the cost per kWh is 10-20% lower for LFP compared to NCA and NMC. NCA and NMC batteries are absolutely available for marine applications, and they store around 33% more energy for the same volume as LFP which makes them a good choice in space constrained applications. But, as you pointed out most marine applications are converting from AGM which is so huge that any Lithium based battery is a win.

If fire safety was the determining factor, LTO would be the battery choice rather than LFP. But nobody's going to make that choice because LTO sucks compared to LFP.

[–] drdabbles@lemmy.world 1 points 3 weeks ago (2 children)

Something to consider is that NMC and NCA cells can use less volatile electrolyte, with several solutions to that particular problem already existing in commercial applications. On top pf that, there are additives to electrode material that can physically separate them from their current collector, thus stopping all electrical flow completely. Panasonic is starting to produce such cells now.

LFP doesn't have a higher cycle life, it has an equal cycle life but with lower current capacity. So at the end of the cell's expected lifetime the LFP cell has stored and discharged vastly less Watt-hours than an NCA or NMC cell. This is a really critical component of the lifetime cost calculation, obviously.

LFP isn't a really good power source, it's an entirely acceptable power source. But in the application of a vehicle where weight is a key factor because road wear increases with the 3rd or 4th power of vehicle weight, any cell technology that requires a physically larger and heavier pack (LFP requires both dimensions be increased) isn't a clear win. LFP is a great technology for stationary storage, though, since the size and weight are much less of a concern.

One of the key things to remember is that any technology that improves one cell type is likely to improve all similar cell types. So as improvements in electrolyte and current collector safety improve with LFP, they also improve with NCA and NMC which makes the latter two more attractive.

[–] drdabbles@lemmy.world 3 points 4 weeks ago

Hard pass on them buying Rivian. I don't want my truck locked into their walled garden. Apple making BEVs makes very little sense at all, but I could see them getting into the infotainment and body controller business if they wanted to branch out in the hardware space.

[–] drdabbles@lemmy.world 1 points 4 weeks ago

As of right now, long haul Class 8 is really not very feasible for BEV. The range is low enough that you don't get a full driving shift out of it, and that's really how long haul vehicles move. I think once we reach that point, though, the 30 minutes per 8 driving hours break (in the US) might be a bit too low to achieve a full 10 or 11 hour driving time day. But the minimum rest time after 10 or 11 driving hours is 8-10 hours which is much more time than would be required to charge on even a 150kW DCFC.

I think we're getting closer to Class 8 being feasible, but it's probably 5 years off or so still. Good to get the infrastructure in place now rather than having it lagging behind when these trucks start showing up in higher numbers.

https://www.fmcsa.dot.gov/regulations/hours-service/summary-hours-service-regulations

[–] drdabbles@lemmy.world 1 points 4 weeks ago

I'm a bit surprised they're deploying 350kW chargers for Class 8 vehicles rather than MCS chargers. Though I'm guessing there's an attempt to strike a balance between easily available utilities services, driving segment length, driving shift length, and charger speed. But when MCS chargers start getting deployed, Class 8 vehicles become much more reasonable.

[–] drdabbles@lemmy.world -3 points 1 month ago

Cool. Yeah, that's how people behave. You should meet more of them, I think. Also, quite a bit of that piece is Fred's opinion, so maybe consider that.

[–] drdabbles@lemmy.world -4 points 1 month ago (3 children)

I figured we were having a discussion. Calling it disinformation is hilarious though.

[–] drdabbles@lemmy.world -4 points 1 month ago (5 children)

Like I said, it doesn't really impact me. So, you can feel how you want to feel. I don't believe anything Tesla says because I've owned one, and I know how they attempt to manipulate their news cycle. I also downloaded the raw data and ran the numbers myself. The Semi does not achieve 500 mile range with a full gross weight traveling at normal highway speeds. You can calculate the rate of SOC decline between data points where the average speed was > 50 MPH and it comes nowhere close.

Now, if on the other hand the title said DHL was happy with their Semi test bed then that wouldn't really be up for dispute. But the instant the title said it achieves 500 miles then I'm sorry but there's no data to support that claim that has ever been published. And I promise you, if such data did exist Tesla would be the first to brag about it incessantly.

[–] drdabbles@lemmy.world 1 points 1 month ago

I did indeed respond.

[–] drdabbles@lemmy.world -2 points 1 month ago

Just so I understand you, you’re saying if Pepsi is positive or neutral on Semi, then your stance is that we cannot take their word for it, and that has to be evidence that Pepsi doesn’t like the Semi. However, if they are negative (as your one employee cited in your one blog post source) then we should absolutely take that as irrefutable fact. Do I have that right? You don’t see any problem with your logic there?

You don't understand me. I'm saying that Pepsi officially has an NDA. I'll also say Pepsi is testing multiple brands of Class 8 Semi as well as lower class vehicles. I think we need to be wary of marketing efforts, because a lot of people don't seem to be able to separate marketing material in press releases from reality. Surely nobody here believes advertising is reality, right? Right?

you really need to cast a critical eye on it.

Great. Now apply that same criteria to Pepsi's PR team. And there we go.

Pepsi seems okay with what was delivered.

This is a different topic than the headline, though. I'm not disputing whether a company would be happy with the Tesla class 8 truck for the right application. I mean, if they compare it to another brand they probably wouldn't be happy, but that's a different topic too. I'm specifically disputing the claim that the Semi meets the sales brochure's claims.

to transport the poison they peddle”

I mean, take that part of the sentence out and I think you'd agree with it. Pepsi has mandates to meet, and credits to claim. That isn't really in dispute in any way, and I'm not even sure that's necessarily a bad thing. But it does explain them putting up with reduced capacity, reduced range, and the breakdowns.

I think you’re looking at the darker blue battery charge

Not only did I read it right but I've processed all the data for all the participants to calculate the consumption at a higher speed. The data is available in CSV format, jump in R or Pandas and do some processing and you'll see what I mean.

I am comfortable with rejecting your conclusion.

Kay. 👍

[–] drdabbles@lemmy.world -3 points 1 month ago (7 children)

I said their numbers were verified in real-world use by third parties.

When you look at the Drive on Less data, it isn't.

I found a “Run on Less” page. Nothing about any testing. Perhaps you have a link?

Um, what are you talking about? Literally the entire campaign is about collecting fleet data over an 18 day period.

LOL what? 500 mile range is a 500 mile range. There is no “how”. There’s only one way that works.

Ok, so then if I can find a 500 mile down hill stretch and I take the battery out completely, I have a 500 mile range. That's what you just said, and I think you know that's nonsense.

Sauce?

See the links I already posted.

I don’t believe you.

Ok. That doesn't really impact me. You can believe the company that his lied constantly about capabilities if you want, that's fine. Not being skeptical at all of their claims makes complete sense given their track record at this point.

[–] drdabbles@lemmy.world -1 points 1 month ago (9 children)

so I don’t see any reason they would do that.

You don't see any reason Tesla would fudge their numbers and drive the Semi slowly? I can think of several reasons.

What testing?

Well you can look at the Run on Less campaign, and then start googling for other tests.

This is how EVs actually work.

Yes, but it's NOT how Tesla claims their 500 mile range. Also, every time a Tesla Semi has attempted the longest range driving, the packs have died. Not just run out of charge, but been physically damaged from draining them so low. You don't have to explain how an EV is operated in real life, I've daily driven one for many years now.

When did Pepsi call them shitboxes?

Well, a Pepsi employee. Obviously Pepsi can't say that in the media because Tesla will take away their vehicles which means Pepsi won't qualify for enough tax credits.

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