60KWh battery for the Bolt... ¿maybe to big for base model 3?

[bxr140]

I consider the Bolt to have a positive effect on Tesla. Tesla will now have to make the Model 3 with a 60 kWh pack minimum.

Agreed. While its easy for tesla to take the high road with S and X and do their own thing in a market that doesnt exist but for them, the high volume 3 will need to compete more directly not just with like priced ICEs, but also other BEVs (like the bolt) on a MUCH more consumer based playing field.

To that end, I think battery capacity is going to become the new horsepower. There are so many variables that such a simple number on paper is all but useless, but to the consumer it is [sometimes inexplicably] everything.

 

[Breezy]

That's interesting. I don't currently have a BEV; I have a Volt. But the #1 question is "How far does it go?" not "What size is the battery?"

I think people would be more impressed by a car that can go 230 miles on 55 kWh, than 220 miles on 60 kWh. I think range is the new horsepower in the BEV world, and it will stay that way until range is on par with comparable gasoline vehicles.

 

[Model 3]

That's interesting. I don't currently have a BEV; I have a Volt. But the #1 question is "How far does it go?" not "What size is the battery?"

I completely agree with you here. But, just like some gets hung up on some HP clams and forget about torque, it looks like people will get hung up on the battery size more then the actual range...

 

[ecarfan]

Just because the Bolt comes standard with a 60kWh battery does not mean that the Model 3 has to match that. More important than battery size is EPA rated range and acceleration time. If the 3 can equal or exceed the Bolt's range (because of a much lower CD) and beat the Bolt's 0-60 time with a slightly smaller battery (while also charging much faster) than most people will view the 3 more favorably. And I am confident that the base 3 will beat the Bolt on all those metrics: range, 0-60, and charge time. Plus it will look a hell of a lot better and have a better UI with a much bigger touch screen.
But until we see the 3 and Tesla announces the basic specs, this is all just guesswork.

 

[david_42]

The Volt has a 18.4 kw-hr battery and a 53-mile range, that works out to a 73.6 kw-hr battery for the Bolt. It certainly doesn't look any more aerodynamic than the Volt, so where are they getting 18% boost in performance? I doubt just pulling the Volt's engine would do the trick.

 

[electracity]

If such a big and heavy car as Model S makes 208 miles with 60 KWh... a smaller car should make at least ¿20% more?

Yes. I think the M3 will have smaller than 60kwh battery to make 200 miles EPA range. I'm doubt that Tesla can afford to make a $35,000 car with a 60 kwh battery.

 

[Jeff N]

The Volt has a 18.4 kw-hr battery and a 53-mile range, that works out to a 73.6 kw-hr battery for the Bolt. It certainly doesn't look any more aerodynamic than the Volt, so where are they getting 18% boost in performance? I doubt just pulling the Volt's engine would do the trick.

Mostly by using a wider state of charge window. BEVs usually allow use of 85-94% of their nominal capacity while plugin hybrids have generally used 63-78%. The Prius Plug-in used 63%, the 2011 Volt used 65%, and the 2016 Volt with its somewhat larger battery and improved cycling durability uses 76%.

Smaller batteries are likely to go through more equivalent full recharge cycles. For instance, my 2011 Volt has been driven about 73,000 miles on battery power at an average of about 45 miles per charge (I drive efficiently). That works out to about 1,600 full charges within its 22% to 87% state of charge window. The equivalent for an S85 with around a 90% state of charge usable range and 250 miles would only be around 300 full charge cycles. Even if you emulated the Volt's more conservative SOC window, the number of charge cycles would about 400 versus the 2011 Volt's 1,600. So, the Volt's battery is being cycled more often but restricting the usable SOC window causes less stress and battery degradation. Also in the Volt's favor is that it's battery construction and chemistry tends to have a higher cycling life than cells designed for maximum energy density like those in a BEV.

Anyway, the Bolt is more like the S85 and can use a much wider SOC window so more of the Bolt's 60 kWh is made available to the driver before a recharge is needed.

Newer inverter and motor designs may also be a little more efficient and the Bolt's simpler gearing means less transmission drag. On the other hand, the Bolt is less aerodynamically efficient than the Volt at highway speeds.

 

[dgpcolorado]

Yes. I think the M3 will have smaller than 60kwh battery to make 200 miles EPA range. I'm doubt that Tesla can afford to make a $35,000 car with a 60 kwh battery.

I don't think that Tesla will have difficulty making a 60 kWh base Model 3 for $35k. I've long believed that 60 kWh will be the minimum size in the M3 and wouldn't be surprised if the base size is larger. What is the cost differential of 5-10 kWh if the battery cost is in the low $100/kWh range? Even at $150/kWh it would be $750 to $1500. It is approaching a de minimis factor in the total cost of the car.

The idea, as I understand it, isn't to hit 200 miles or match the Bolt. The idea is to exceed 200 miles of real world range and beat the competition in both range, performance, and styling. I'd be surprised if Tesla doesn't succeed at that.

 

[EVNow]

There are many threads about this here.

A good approximation is 4 miles/kWh - of useable capacity. To get 200 EPA miles you need, 50 kWh useable or about 55 kWh total. But you can't cut it so close - since the efficiency can go up or down a bit when the car is finally finished. Tesla needs a bit of buffer (just like GM has chosen to have) - that is why they will go with closer to 60 kWh total and about 55 kWh useable.

If Tesla can really hit even $150 / kWh - we are talking about just $750 to ensure that the base car will come at > 200 EPA miles. Musk has been talking about 200 miles minimum for years. It would take a really stupid and reckless chief engineer to go with less than 60 kWh and explain to Musk why base Model 3 will have less than 200 miles EPA range .. but that kind of engineer wouldn't have lasted in Tesla in the first place.

 

[Jopo43]

wthout a real charging network i will wait on the model 3

 

[scottf200]

wthout a real charging network i will wait on the model 3

Because this is your roadtrip type of car vs commuter car?!?! i.e. 200 mile cars

 

[nwdiver]

Because this is your roadtrip type of car vs commuter car?!?! i.e. 200 mile cars

The logistics of even ~100 miles trips (one-way) are far easier and less stressful if there's a supercharger nearby.

 

[trils0n]

My rough, back-of-the-napkin estimate puts the Model 3 battery around 60kWh.

Gigafactory has been indicated to produce 35gWh of cells each year for 500k cars. Roughest estimate would be: 35,000,000 kWh of cells / 500,000 cars = 70kWh / car.

Getting (perhaps) a little more accurate: 100,000 Model S and Model X at 90kWh = 9,000,000 kWh.

That leaves 24,000,000 kWh and 400,000 cars.

24,000,000 kWh / 400,000 cars = 60kWh / car

Unknown is: actual numbers for Model S and X production and capacity, how the total pack size assembly (indicated at 50gWh) for the Gigafactory figures in, how much the rest of Panasonic's cell production at other factories contributes, Tesla Energy, etc. Perhaps the more of those variables that can be answered, the more accurate guess could be made for Model 3 battery size.

 

[Peter Egan]

Tesla must have a significant technology lead over GM. We should expect more Tesla range per tonne of car.

 

[physicsfita]

Because this is your roadtrip type of car vs commuter car?!?! i.e. 200 mile cars

At least for myself, and I'm sure for many others, whatever car they own is their only car -- that changes the shopping considerations quite a bit.

 

[doubeld]

My rough, back-of-the-napkin estimate puts the Model 3 battery around 60kWh.

Gigafactory has been indicated to produce 35gWh of cells each year for 500k cars. Roughest estimate would be: 35,000,000 kWh of cells / 500,000 cars = 70kWh / car.

Getting (perhaps) a little more accurate: 100,000 Model S and Model X at 90kWh = 9,000,000 kWh.

That leaves 24,000,000 kWh and 400,000 cars.

24,000,000 kWh / 400,000 cars = 60kWh / car

Unknown is: actual numbers for Model S and X production and capacity, how the total pack size assembly (indicated at 50gWh) for the Gigafactory figures in, how much the rest of Panasonic's cell production at other factories contributes, Tesla Energy, etc. Perhaps the more of those variables that can be answered, the more accurate guess could be made for Model 3 battery size.

Your math is slightly off. 35GWh - 9GWh = 26GWh = 65kWh for 400,000 cars. I would be happy with this number too

Another unknown is how soon a second or third GF can come online. I am guessing GF2 will be in Germany, GF3 in Japan/China, GF4 in South Africa or maybe Australia. If Tesla can go from ground prep in May 2014 to producing packs at GF1 in Dec 2015, that means they could start construction at another site sometime this quarter and have it starting to produce packs by the time the first TM3 rolls off the production line. All this demand is worldwide, not just in the USA after all!

 

[trils0n]

Your math is slightly off. 35GWh - 9GWh = 26GWh = 65kWh for 400,000 cars. I would be happy with this number too

Another unknown is how soon a second or third GF can come online. I am guessing GF2 will be in Germany, GF3 in Japan/China, GF4 in South Africa or maybe Australia. If Tesla can go from ground prep in May 2014 to producing packs at GF1 in Dec 2015, that means they could start construction at another site sometime this quarter and have it starting to produce packs by the time the first TM3 rolls off the production line. All this demand is worldwide, not just in the USA after all!

Oops :redface: What a weird mistake. Just looked at the post it note I wrote the math on, and I wrote 26GWh and 65kWh per car. Somehow when I typed it up I got it very wrong, hah.

 

[igotzzoom]

I plan on getting a portable EVSE and a bag full of adapters if I get a Bolt. Sure, not as elegant as Tesla, but still doable.

 

[ImEric]

There are many threads about this here.

A good approximation is 4 miles/kWh - of useable capacity. To get 200 EPA miles you need, 50 kWh useable or about 55 kWh total. But you can't cut it so close - since the efficiency can go up or down a bit when the car is finally finished. Tesla needs a bit of buffer (just like GM has chosen to have) - that is why they will go with closer to 60 kWh total and about 55 kWh useable.

If Tesla can really hit even $150 / kWh - we are talking about just $750 to ensure that the base car will come at > 200 EPA miles. Musk has been talking about 200 miles minimum for years. It would take a really stupid and reckless chief engineer to go with less than 60 kWh and explain to Musk why base Model 3 will have less than 200 miles EPA range .. but that kind of engineer wouldn't have lasted in Tesla in the first place.

I think you're probably right that 4 mi/kWh is a good estimate. But if Tesla can reduce the weight (with a smaller, more energy dense battery than we're used to with the models S, and fewer cells at that), and a drag coefficient of under .2, is it possible they could get that up to even 4.25 mi/kWh? Now we're talking about 47 kWh to get to 200 miles. Then a 55 kWh battery with, say 51kWh available could possibly take the car about 215 mi. Is an additional 6% increase in efficiency coming from vehicle dynamics and/or mechanics such a far stretch? JB Straubel has already stated that they plan for new cells from Gigafactory 1 to have a different, larger form factor (no more 18650) which will allow for greater energy density even using the same cell chemistry. That alone will allow for a pretty significant weight reduction. And then there was the "90D" announcement last year when Musk said that due to changes in cell chemistry, they expect to be able to increase range about 5-6% every year. I can't imagine that holds only to the Model S/X. That said, changes in Tesla's battery chemistry since 2012 should be able to drive a 2012 MS60 about 250 miles in 2016 with equivalent cell volume.

Of course... I know very little about Chemistry or Engineering, and even less about Tesla's secret plans for the M3, so this is mostly just wild conjecture.

 

[EVNow]

CD of less than 0.2 ? As likely as GM building a super charger network for Bolt.