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

[mitch672]

In 2017 (or perhaps a bit earlier, hard to say now), Tesla will have their Gen3 200 mile+ car out, with a nationwide network of DC Fastchargers...

Have you seen the Japanese QC network. One every 15x15 miles. To cover the US we need twenty thousand, not hundreds.

With a 200 mile+ range car you need far fewer DCFC than with a 75-100 mile range car, it's no where near 20 thousand. This is for long distance travel between cities, as you know most EVs are charged at home or your destination. No one wants to stop every 75-100 miles to charge, it's impractical for LD travel if displacing the ICE (Teslas stated goal)

Look for Teslas announcement tomorrow, 3X the SuperChargers by the end of 2013, enabling coast-coast travel in a Model S. Elon let the announcement out tonight at the All things Digital conference: http://allthingsd.com/tag/elon-musk/" onclick="window.open(this.href);return false;

 

[lion]

I'm still interested in how all this 'supercharging' is affecting battery life. I'm no expert, but this has to affect battery life one way or another.

 

[TomT]

This will help:

"Tesla Motors Inc.'s Chief Executive Elon Musk said on Wednesday the company will triple its network of superchargers for electrical vehicles by the end of next month."

http://www.dailynews.com/breakingnews/ci_23352540/tesla-supercharger-network-triple-june" onclick="window.open(this.href);return false;

 

[DaveEV]

I'm still interested in how all this 'supercharging' is affecting battery life. I'm no expert, but this has to affect battery life one way or another.

If you can keep the batteries cool, the effect is probably not all that much. We're still only talking about 1-2C at most - most lithium chemistries can handle this fine.

 

[evnow]

With a 200 mile+ range car you need far fewer DCFC than with a 75-100 mile range car, it's no where near 20 thousand.

But that was not the premise of OP. He was saying if you had the density of Japanese QC, would you still need a 200 mile range EV. You are saying if we have a 200 mile range EV, you won't need the density of QC in Japan.

I'm saying it is all theoretical since we will probably have 200 mile 30k EV before we can come close to getting QC at the density of what is in Japan.

 

[Nubo]

With a 200 mile+ range car you need far fewer DCFC than with a 75-100 mile range car, it's no where near 20 thousand. This is for long distance travel between cities, as you know most EVs are charged at home or your destination. No one wants to stop every 75-100 miles to charge, it's impractical for LD travel if displacing the ICE (Teslas stated goal)

Yes, that works for "A" car. But I think a lot of folks don't do the math of miles dispensed per unit time. Or stated another way, how much power do you have to deliver to keep X number of vehicles moving along the highway?

Consider a highway service plaza. There may be multiple gasoline stations. To make a round number let's say the plaza has 10 pumps; that's probably conservative. If it takes 5 minutes to fuel and turn around a vehicle, the plaza can fill 120 cars per hour. Let's say this adds 300 miles of range to each vehicle. So the plaza can deliver 36,000 miles of range per hour. And these services are located far more frequently than every 200 miles.

Now say you have a Tesla fast charger. Best case is 300 miles delivered per hour.

To match the miles-delivered of just one modest gasoline service plaza, you would need... wait for it.... One Hundred and Twenty Tesla fast-chargers!

Fortunately, most charging is, and will always be done at home. Still, we are going to need a significant amount of infrastructure to support long-distance EV travel when the EV fleet reaches a significant percentage of cars on the road. One lonely outpost every 200 miles is the pioneer stage.

But by all means, hats off to Elon for jump-starting the process! :mrgreen:

 

[GregH]

I find this whole discussion of 200 mile range EVs somewhat amusing..
As an engineer, the thought of spending a bunch of extra money (and vehicle weight) for something that is rarely used seems rather foolish.

Well, how many of us buy a single seater ?

Ha! Well if I could trade in my Leaf to get my old EV1 back...
Actually years back I had one of those little 2 door RAV4 (gas) cars and took one of the back seats out to get more storage as it was never used. Maybe I'm the wrong guy to answer that question!

If you had a car with X range there will always be that one trip you couldn't make because you needed X*1.2 range. If you really want to lug around dead weight for that occasional long trip, get a Volt.

But as the range increases, the % of trips for which you need a rental/ICE decreases - and as that happens more and more people switch from ICE to EV.

Yes.. so where is the sweet spot? Granted if batteries years from now cost 1/3 what they do today then sure.. why not. I admit the 60-75 miles many Leafers see is a bit on the low end (although still more than some early EV1s). Way back in 1999 before one of the CARB hearings we did a survey of current Production EV Drivers as to the ideal range for an EV and the biggest response was 90 miles (more so than 100 miles). The question did have a dollar figure on it though.. I forget the number.

Also, if the Chademo map for the US looked anything like the map for Japan would you really need/want 200 miles?

I'm afraid by the time we get a dense network of QCDC, we will also have a 200 mile Leaf for $30k.

Yeah, that'll be terrible...

 

[Deleted member 8423]

If you can keep the batteries cool, the effect is probably not all that much. We're still only talking about 1-2C at most - most lithium chemistries can handle this fine.

Why does DCFC increase the temp significantly on the Leaf battery while Supercharging barely moves the needle?

 

[mitch672]

If you can keep the batteries cool, the effect is probably not all that much. We're still only talking about 1-2C at most - most lithium chemistries can handle this fine.

Why does DCFC increase the temp significantly on the Leaf battery while Supercharging barely moves the needle?

4 words: Tesla uses liquid cooling
Nissan doesn't

Edit: also a 50KW Chademo DCFC charging a 24KW Leaf pack at full power could be 2C, while a 120KW SuperCharger charging an 85KW Model S pack at full power is 1.4C, the Leaf is air cooled so it will likely have to taper the charging rate sooner than the liquid cooled Model S pack.

 

[evnow]

Well, how many of us buy a single seater ?

Ha! Well if I could trade in my Leaf to get my old EV1 back...
Actually years back I had one of those little 2 door RAV4 (gas) cars and took one of the back seats out to get more storage as it was never used. Maybe I'm the wrong guy to answer that question![/quote]
I asked "how many", not "would you buy".

Anyway, it was obviously a rhetorical question. Even though most of my trips are alone, I still want to buy a 4/5 seater. We don't have the luxury of having dozens of cars suitable for various scenarios. We buy 2 cars per household (mostly) and they have to fulfill a large number of scenarios.

Yes.. so where is the sweet spot?

"200 miles" Tesla range is good. That would mean on a winter day, on freeway I can perhaps go 120 miles or so. I think when you can drive on a freeway for 3 hours and recharge in 30 minutes, the ICE is dead.

 

[mitch672]

"200 miles" Tesla range is good. That would mean on a winter day, on freeway I can perhaps go 120 miles or so. I think when you can drive on a freeway for 3 hours and recharge in 30 minutes, the ICE is dead.

That's where the 85KW Model S will be at the end of 2014, after the vast majority of the SuperCharger network is deployed... Within a year or two from that point, Teslas 3rd Gen 200+ mile lower cost EV that uses the SC network will be mass produced.

We can already do this on the east and west coasts in limited areas (where the SC have been deployed), charging time was just decreased as they have increased SC power from 90 to 120KW (to be fully deployed within the next 3 months), and they are now tapering much later in the charging process, result is SC time has been halved.

 

[MikeD]

"Elon Musk: Humanity has two options, become multiplanetary or go extinct" -- link: http://www.rawstory.com/rs/2013/05/30/elon-musk-humanity-has-two-options-become-multiplanetary-or-go-extinct/" onclick="window.open(this.href);return false;

So does he really mean "What Mars really needs is a great, affordable EV"?

Also "Radiation measurements suggest new obstacle in human trip to Mars" -- link: http://www.rawstory.com/rs/2013/05/30/radiation-measurements-suggest-new-obstacle-in-human-trip-to-mars/" onclick="window.open(this.href);return false;

 

[Nubo]

"Elon Musk: Humanity has two options, become multiplanetary or go extinct" -- link: http://www.rawstory.com/rs/2013/05/30/elon-musk-humanity-has-two-options-become-multiplanetary-or-go-extinct/" onclick="window.open(this.href);return false;

So does he really mean "What Mars really needs is a great, affordable EV"?

Also "Radiation measurements suggest new obstacle in human trip to Mars" -- link: http://www.rawstory.com/rs/2013/05/30/radiation-measurements-suggest-new-obstacle-in-human-trip-to-mars/" onclick="window.open(this.href);return false;

Plastic space ships to the rescue?

http://science1.nasa.gov/science-news/science-at-nasa/2005/25aug_plasticspaceships/" onclick="window.open(this.href);return false;

 

[DaveEV]

If you can keep the batteries cool, the effect is probably not all that much. We're still only talking about 1-2C at most - most lithium chemistries can handle this fine.

Why does DCFC increase the temp significantly on the Leaf battery while Supercharging barely moves the needle?

4 words: Tesla uses liquid cooling
Nissan doesn't

Edit: also a 50KW Chademo DCFC charging a 24KW Leaf pack at full power could be 2C, while a 120KW SuperCharger charging an 85KW Model S pack at full power is 1.4C, the Leaf is air cooled so it will likely have to taper the charging rate sooner than the liquid cooled Model S pack.

Expanding on what Mitch said, when I said "1-2C" I wasn't talking about temperature rise, but talking about charge rate where 1C = charging at a rate that would fully charge a battery in 1 hour. 2C = charging at a rate that would fullly charge a battery in 30 minutes. Charging at 2C is pretty easy for lithium chemistries as long as the SOC is low, obviously this gets harder as the battery fills up which is why the charge rate tapers down at some point.

For example, the LEAF will QC at up to 120A up until the pack voltage hits ~394V at which point it starts tapering the current down to keep voltage from going over 394V. It's a standard constant current then constant voltage charge profile. The Model S is similar except that it is designed to take a max of over 200A!

 

[GregH]

Edit: also a 50KW Chademo DCFC charging a 24KW Leaf pack at full power could be 2C, while a 120KW SuperCharger charging an 85KW Model S pack at full power is 1.4C, the Leaf is air cooled so it will likely have to taper the charging rate sooner than the liquid cooled Model S pack.

True.. But calling a Leaf pack "air cooled" is being overly generous. It's a sealed box. The Tesla should taper same as a Leaf on ChaDeMo.. Based on voltage.

 

[AndyH]

True.. But calling a Leaf pack "air cooled" is being overly generous. It's a sealed box. The Tesla should taper same as a Leaf on ChaDeMo.. Based on voltage.

Not generous at all. Heat is conducted from the cells to the 'sardine can', the battery box internal structure, and to the battery box. All the rest is air.

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.

 

[GregH]

True.. But calling a Leaf pack "air cooled" is being overly generous. It's a sealed box. The Tesla should taper same as a Leaf on ChaDeMo.. Based on voltage.

Not generous at all. Heat is conducted from the cells to the 'sardine can', the battery box internal structure, and to the battery box. All the rest is air.

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.

Sorry, should have clarified.. No forced air. All the ACP cars we have here have huge blower fans for the battery (and motor controller). The old RAV4-EV also had forced air as did the gen2 EV1 but newer regulations requiring submersible battery packs prohibit forced air cooling nowadays.

 

[evnow]

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.

Hasn't Tesla now shifted to Li-Al-Co cells ?

 

[DanCar]

Hasn't Tesla now shifted to Li-Al-Co cells ?

Where did you hear this?

 

[Stoaty]

Hasn't Tesla now shifted to Li-Al-Co cells ?

Where did you hear this?

Look at this thread:

http://www.teslamotorsclub.com/showthread.php/12709-18650-Batteries" onclick="window.open(this.href);return false;

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;