Question About 4680 Cells

[Ogre]

No. They both start with 80% charged battery and they both leave the charger at 320 miles with 80% charge.

Nope. One leaves the charger with 400 miles of range. The other has 240 miles of range. Try again with the same actual range remaining at the end.

Nobody drives in percentages, they drive MILES. Try telling the story using *miles range* instead of percentages and your story no longer makes any sense.

The trips from ABRP tell the story.

 

[Dids]

Nope. One leaves the charger with 400 miles of range. The other has 240 miles of range. Try again with the same actual range remaining at the end.

Nobody drives in percentages, they drive MILES. Try telling the story using *miles range* instead of percentages and your story no longer makes any sense.

The trips from ABRP tell the story.

ABRP is broken. It thinks it's over 1000 miles to Norfolk VA from boston.

 

[Ogre]

ABRP is broken. It thinks it's over 1000 miles to Norfolk VA from boston.

It's highly recommended in the Tesla community... but whatever.

The only way you make your example "works" is by making the CT3 driver stand around waiting for an extra 160 miles of range.

 

[Dids]

It's highly recommended in the Tesla community... but whatever.

The only way you make your example "works" is by making the CT3 driver stand around waiting for an extra 160 miles of range.

I found the error. It was round trip...
Yes abrp shows CT 3 charging once.
They use 2 wh/ mile difference between the 2 as penalty for the extra weight.
Have fun driving for 10 hrs and only stopping once.

 

[ajdelange]

Nobody drives in percentages, they drive MILES. Try telling the story using *miles range* instead of percentages and your story no longer makes any sense.

I do. It makes planning and fuel situation estimation very simple. I need to go 175 mi. That's half of 350 i.e 50%. I have 64% in the battery now so I'll arrive with 14%. Each percent is 3.5 miles so ill have 42 + 7 miles left. I'll want to charge back up to 70% before returning meaning I'll need to add 56% which will take me a little more than 30 + 4 minutes (charge rate is a bit slower than 1C for my Tesla).

The trips from ABRP tell the story.

ABRP is indeed a better route planner. It can't be beat. But it is forced to assume that a particular model of car at a particular model of charger will always charge the same way. That's not true. Here, for example, are two charges from the same terminal at the same station (Lebanon, NH) two days apart:

The upper charge was at the expected 0.97C but the other, even though it didn't gp into the region where the taper is expected to be dramatic, only averaged 0.71C.

 

[Ogre]

I found the error. It was round trip...
Yes abrp shows CT 3 charging once.
They use 2 wh/ mile difference between the 2 as penalty for the extra weight.
Have fun driving for 10 hrs and only stopping once.

Nothing precludes you from stopping more than once.

Or for that matter, stopping at the same supercharger the CT2 stops at and just not staying as long. In fact I suspect that's what most people would do. Stop long enough to pee, get in the truck and keep driving.

Why would you do otherwise?

 

[ajdelange]

The prudent man looks at his SoC at arrival, figures how many % he needs to add to get to his next stop (or lets the navigator do that for him), adds that to the SoC he's got. adds any additional margin he wants, sets the charge level for that and waddles off to the bagel shop. Or just puts the next stop in the navigator, starts charging, waddles off to the bagel shop and waits for the "your car is sufficiently charged to continue your journey" e-mail.

 

[Dids]

Nothing precludes you from stopping more than once.

Or for that matter, stopping at the same supercharger the CT2 stops at and just not staying as long. In fact I suspect that's what most people would do. Stop long enough to pee, get in the truck and keep driving.

Why would you do otherwise?

With the moral of the story being that in the end they both arrive at the same time?

 

[Ogre]

With the moral of the story being that in the end they both arrive at the same time?

Works for me.

Though perhaps the real moral of the story is how easy it is for 2 rational people to talk past each other for 8 posts running.

 

[Dids]

Works for me.

Though perhaps the real moral of the story is how easy it is for 2 rational people to talk past each other for 8 posts running.

We are very bored.

 

[jhciv]

This conversation, while entertaining, ignores that the CT3 can do more trips with no en route charging than the CT2. I own a camping spot ~90 miles from my house. Towing my ~3500lb camper I can be confident that in the CT3 I'll get there and home, and have power at the campsite, even with a 40+% range reduction. Not possible in the CT2.

Moral of the story: sufficient range is use-dependent.

 

[Crissa]

Tapering will quickly rob any charge speed advantage the 300 mile battery has over the 500 mile battery. If you are adding 250 miles range (about 80% range on a Model Y), when you roll away from the charger, the charge rate is going to be about 50kW.

Charging a 500 mile range battery to that same 250 miles range means you unplug at a 50% state of charge and the charge rate is 110kW. Even though you've pushed more energy into the battery, staying to the left side of the tapering curve longer means you add miles of range faster.

That assume the same cooling to mass profile, which would also have to double, and that would add loads more weight in coolant and condenser coils.

So there are still diminishing returns. Bigger battery, more weight, bigger cooling, also more weight, also more power devoted to cooling while recharging, more concentrated mass so it'll be radiating more poorly, etc.

Lots of factors both positive and negative.

-Crissa

PS, tapering does happen at home, but it's up in the 90+% range or if it's incredibly hot or cold out.

 

[Ogre]

Lots of factors both positive and negative.

Also, to make the whole thing weirder, it's possible they could use different battery chemistries in the tri motor truck to keep the weight down. That would throw any of this out the window as the different chemistries might taper differently, and definitely respond differently to deep cycling.

 

[Bob Anderson]

What do you guys think about this article? Will 4680's be that quick to charge?

https://insideevs.com/news/448893/tesla-model-3-4680-charging-power-size/

 

[Crissa]

We can hope. I don't think they're pushing the current cells to their limits, so it's hard to know.

-Crissa