Musk : What the world really needs is a great, affordable EV

[GregH]

Edit: Here is the direct link to PDF file where the calendar life and cycling of said batteries was studied:

http://www.teslamotorsclub.com/attachment.php?attachmentid=10719&d=1350500751" onclick="window.open(this.href);return false;

Wow.. What a fantastic amount of information on a single page. Would love to see those graphs for the 33Ah cells in the Leaf.
I wonder if the 400mAh is a typo and they really mean 3400mAh? I had heard the latest 18650s used by Tesla (and tested in some other vehicles I've seen) were currently 3.4Ah. I'd also heard 4.0Ah was around the corner. Pretty mind blowing considering state of the art was 2.0 or 2.2Ah not long ago.

 

[DaveEV]

Don't forget, as we reopen the Tesla VS Leaf battery debates, that Tesla's using cylindrical lithium cobalt cells (as in laptop battery) while the Leaf is using 'pouch' lithium manganese variants. The Leaf battery simply does not produce as much heat, and has much more surface area to conduct heat away.

If we were talking about single cells, you'd probably be right, but because the LEAF cells are packed into modules which are then stacked, there really is not much surface area at all to conduct heat away. Tesla's pack has room for a water-cooling tube to be wrapped around both sides of each cell. Of course, pouch cells could have water cooling plates sandwiched in between modules like the Volt does - this should result in better cooling than trying to cool laptop cells the way Tesla does.

 

[RegGuheert]

Edit: Here is the direct link to PDF file where the calendar life and cycling of said batteries was studied:

http://www.teslamotorsclub.com/attachment.php?attachmentid=10719&d=1350500751" onclick="window.open(this.href);return false;

Thanks, Stoaty! Very interesting!

One thing that jumps out at me from that paper is that is doesn't take very many days at 90% SOC to lose 10% of your battery capacity, even at room temperature.

 

[AndyH]

Don't forget, as we reopen the Tesla VS Leaf battery debates, that Tesla's using cylindrical lithium cobalt cells (as in laptop battery) while the Leaf is using 'pouch' lithium manganese variants. The Leaf battery simply does not produce as much heat, and has much more surface area to conduct heat away.

If we were talking about single cells, you'd probably be right, but because the LEAF cells are packed into modules which are then stacked, there really is not much surface area at all to conduct heat away. Tesla's pack has room for a water-cooling tube to be wrapped around both sides of each cell. Of course, pouch cells could have water cooling plates sandwiched in between modules like the Volt does - this should result in better cooling than trying to cool laptop cells the way Tesla does.

I agree that each four-cell can is a unit, but there is still a full conduction path to the outer case. Again - it's really important that the LiMn cells don't generate as much heat as LiCo - they simply don't need as large a conduction path. There's at least one LiMn variant on the street that cools when charging...

 

[DaveEV]

I agree that each four-cell can is a unit, but there is still a full conduction path to the outer case.

Are you sure about that? I'd be very surprised if there isn't an air-gap between the modules and outer case. All the pictures of the pack I've seen (including in person with the cut-away show packs) show about 1/2" of air between the modules and outer case.

 

[RegGuheert]

Are you sure about that? I'd be very surprised if there isn't an air-gap between the modules and outer case. All the pictures of the pack I've seen (including in person with the cut-away show packs) show about 1/2" of air between the modules and outer case.

I'm pretty sure Andy is talking about the bottom of the case and not the sides. I, too, am under the impression that there is a good conduction path to the bottom plate so that the air flowing underneath the battery pack while driving can cool it (assuming ambient is cooler than the batteries).

 

[JeremyW]

Here's a fascinating post on Tesla's modification of the 18650 form factor in the Model S pack:

Amazing Core Tesla Battery IP - 18650 Cell

 

[AP1]

http://www.autoweek.com/article/201...eaf-fighter-in-2016&utm_campaign=awdailydrive

 

[Petecomp1]

... And 2016 is when my lease expires! But our 2013 Leaf is so perfect for us, excepting the range, hope this will spur Nissan to get with the program on upping Leaf range to ~200 miles.

 

[oxo]

Just like with the NFL - competition makes everyone better! Yay!

 

[apvbguy]

I'll send them a deposit the moment it becomes a reality

 

[RegGuheert]

From the article:

He hinted that the Superchargers could recharge a car faster than a gasoline counterpart.

That's interesting!

Then this:

On the retail front, despite recent setbacks in Texas, North Carolina and Virginia, Tesla will continue to battle national and state auto dealer associations regarding the automaker's factory-store model, Musk said.

Virginia, again? What is it with these idiots and electric cars? Time to clean house methinks...

 

[Sublime]

I thought I also heard him mention that autopilot may debut on this model.

 

[LTLFTcomposite]

I thought I also heard him mention that autopilot may debut on this model.

Just so we don't have to deal with the emergency inflation device.

Nissan needs to up their game. 200 miles would be awesome, but an honest 120 would be a big step forward.

 

[TomT]

Yep, my next EV has to have a minimum real range of 100 miles at a true 65 mph freeway speed.

Nissan needs to up their game. 200 miles would be awesome, but an honest 120 would be a big step forward.

 

[Smidge204]

From the article:

He hinted that the Superchargers could recharge a car faster than a gasoline counterpart.

That's interesting!

Gasoline dispensers are limited to 10GPM. Let's say the average is 5 GPM. That's 3-6 minutes for your typical vehicle.

So let's say you had a 30kWh pack and you want to fully recharge that in 5 minutes.

30 kWh * 60 Min / Hr * 1/5 Min = 360 kW.

It's not clear where that kind of instantaneous power is going to come from, but the required cable will likely be as thick as a soda can. :/
=Smidge=

 

[Sublime]

From the article:

He hinted that the Superchargers could recharge a car faster than a gasoline counterpart.

That's interesting!

Gasoline dispensers are limited to 10GPM. Let's say the average is 5 GPM. That's 3-6 minutes for your typical vehicle.

So let's say you had a 30kWh pack and you want to fully recharge that in 5 minutes.

30 kWh * 60 Min / Hr * 1/5 Min = 360 kW.

It's not clear where that kind of instantaneous power is going to come from, but the required cable will likely be as thick as a soda can. :/
=Smidge=

I come up with a similar charge rate for 80% of the 85kWh pack in 12 minutes (a figure most would let him slide on). That's 3x the current rate, which would mean 9x the heat over the same line. Sounds dangerous. Guess we'll find out on the 20th.

 

[vsiev]

From the article:

He hinted that the Superchargers could recharge a car faster than a gasoline counterpart.

That's interesting!

Gasoline dispensers are limited to 10GPM. Let's say the average is 5 GPM. That's 3-6 minutes for your typical vehicle.

So let's say you had a 30kWh pack and you want to fully recharge that in 5 minutes.

30 kWh * 60 Min / Hr * 1/5 Min = 360 kW.

It's not clear where that kind of instantaneous power is going to come from, but the required cable will likely be as thick as a soda can. :/
=Smidge=

I'm guessing Elon is referring to the gas counterpart as:
1. Try to use Credit Card at the pump but get "see cashier"
2. Go in store and realize you're thirsty
3. Get a drink, get in line and wait
4. Realize you want a snack
5. Get a snack, get back in line and wait
6. Pay for the items and gas (fill up)
7. Pump your gas
8. Go in store to get actual receipt of gas filled.

So I think Elon's statement is pausible.

 

[RegGuheert]

...the required cable will likely be as thick as a soda can.

Note to self:

1) Invent superconducting EVSE charging cables.
2) License them the Elon Musk and Carlos Ghosn.

 

[Zythryn]

I thought I also heard him mention that autopilot may debut on this model.

He said he would like to see it. But basically it is just a distant possibility right now.
Basically, if it becomes available, they will consider it, but I wouldn't plan on it.