How many kWh can they squeeze into the Model 3...?

[garsh]

just because Ludicrous has been confirmed doesn't necessarily mean there must be a larger battery pack. You can definitely get quicker than ludicrous times with a pack smaller than 50 kWh, range suffers, but it's not impossible.

The problem is a limit to the amount of current each individual cell can source. If you have more cells in your pack, then the pack itself can deliver more current.

 

[ModelNforNerd]

The problem is a limit to the amount of current each individual cell can source. If you have more cells in your pack, then the pack itself can deliver more current.

I think with the evidence of the 300kW inverter being sourced for the Model 3, we can probably expect a "good-sized" battery.

Otherwise, why bother with such a robust inverter?


I can't wait.

 

[jbcarioca]

But why would you think that the exponential growth of your computer's RAM capacity would say anything about the growth of energy density in batteries?

Until now, the battery energy density has been improving exponentially, at about 7% annually.

...

We do need to remember that improvements in nearly all the energy usage factors (e.g. inverters, circuitry, vehicle control, battery management, heating and cooling, lighting) will yield very substantial improvements to effective range. Motors may see some improvement too, probably less significant, but if DC motors can be made to be practical, the improvements even there may be notable.

In other words kilowatt-hours is not the whole story, albeit it is one of the most important parts of the story.

 

[JeffK]

The problem is a limit to the amount of current each individual cell can source. If you have more cells in your pack, then the pack itself can deliver more current.

The current model S is not using anywhere close to the limit. There are at least two other systems zombie 222 and flux capacitor that are using greater than 2000 amps from a smaller battery pack, both can accelerate faster than the P90DL .

 

[glenhurst]

If JB prognosticates correctly we'll see roughly double the battery pack weight/price effectiveness in less than a decade (7% pa on average, he says). Then there is continuous improvement in inverters, motors, passive loads, connections, etc. All in all we certainly will see at least 10% pa typical improvement, even though quite a large proportion will come with substantial hardware changes.

Switching to, say, 48v support systems by itself should reduce vampire drain by half or so, even though that will only happen when much of the industry changes, inevitable despite no idea when. I'll wager the advent of driving assistance (autopilot, etc) during the next five years will accelerate an industry-wide shift to higher voltage.

Then, most major manufacturers are launching several BEV's within the next couple of years. They'll all prefer higher voltage.

The industry movement will, IMHO, spawn rapid improvements in inverters, cell design/chemistry, battery management systems and electrical infrastructure in vehicles. Tesla will no longer be forced to do everything itself, and scale economies will grow.

So I am an optimist, but hopefully a realistic one.

What is the appeal of 48v?

 

[Red Sage]

My first computer in 1990 had 4MB memory. Everybody told me it's totally foolish to buy such a huge computer
I think in 20 years we will laugh about a car with poor 75 kwh

This is the very essence of my position about future improvements in battery technology. If, within twenty years of the original Model S launch, energy density doubles only twice...? Then the number of battery cells that currently holds 90 kWh will probably offer 160 kWh to 180 kWh before 2020, and well over 300 kWh by 2030. Thus, increasing range with the same number of battery cells, or increasing range with fewer battery cells. Either way, things will be looking up for electric cars as the battery cells get less expensive, and more profitable.

 

[Red Sage]

Tesla has just come out with 60 kWh versions of S and X. The supercharger network appears to be designed to work for these cars. A 215 miles model 3 will likely also be disigned to fit this model. Tesla is in the process of proving 200 miles works well. They will not likely add unpaid for batteries to the model 3, with the hope of an upgrade. I am not sure that a larger battery will even be an option. Remember, it is all about the 3.

We'll see. I think that when taking cars as trade-ins, the 55 kWh cars would simply be resold as 75 kWh CPO cars instead. I'm pretty sure that whenever a Model S 40 is traded in, it is resold as a Model S 60. More revenue on resale. Tesla Motors saves money with inventory control systems by not having to build or store or distribute a 55 kWh specific battery pack. Tesla Motors makes money when buyers of the 55 kWh version decide to upgrade later. Tesla Motors makes money when an older 55 kWh vehicle is resold as a higher capacity used car.

 

[Red Sage]

Why would you want to lock the D option behind the bigger battery?

Uhm... I wouldn't want to... If it were up to me, the entire Model ☰ line would be solely dual motor all wheel drive configuration.

However, Elon Musk announced during 2015 and has reiterated since that the base version of Model ☰ would be rear wheel drive. I expect that a Model ☰ 55 with a single motor will actually be built with the same 'bigger battery', only software limited to 55 kWh instead of 75 kWh. Please note that there are those who feel the opposite of you, in that they do NOT want dual motors, or all wheel drive, at all. They prefer rear wheel drive to anything for some reason. This also allows people to have a Model ☰ 75 -- without the 'D' if they want. I doubt they will ever get an 'official' Model ☰ P75, though... They'd have to purchase larger wheels and tires separately, maybe with a spoiler, and probably would.

I definitely want AWD but will likely not be able to afford a higher end battery option with all the other options that I want. My daily commute is 3-5 miles to work and back with a little grocery shopping once a week. I almost never drive longer distances but I will still get the SC access on day one for the convenience of having the option when I need it. Therefore the best outcome for me would be if I could get a software limited Model ☰ 55D with an option to unlock it to 70D or 75D after purchasing the car.

You might get that option. I'm just some guy on the internet making guesses. What do I know?

 

[Red Sage]

Base model 50 kwh will be good for 220 miles
Big battery will be 70 kwh and good for 305 miles. This car weighs 1000 pounds less (or more) than Model S.

Possibly. But what you propose would require either under 185 Wh per mile, or under 190 Wh per mile, energy consumption on average. That might be possible, if Nissan or Chevrolet were releasing the Model ☰ as an underpowered slowpoke gimpmobile... Or if you intend to drive the car like a Hippie Treehugger... But Tesla Motors has a dedication to both Range and Performance.

I'm not so sure that weight has that big an affect on range. The original Rimac Concept One had less range than the Tesla Model S 85, but after being upgraded to a 93 kWh capacity Rimac claims over 300 miles range. The Mercedes-Benz SLS AMG Electric Drive (66 kWh) had less range than the Tesla Roadster (53 kWh) and the same 0-60 MPH time. The Model S 40 weighed about 400 lbs more than the Toyota RAV4 EV, but still had a greater range by 36 miles.

I maintain that in order to achieve an EPA rating of 300 miles or more, the Model ☰ will offer battery packs of 90 kWh and higher. I think that the highest capacity battery pack may only be offered on the Performance version of the car only. I expect that most will find that the medium capacity battery pack is 'enough' for their needs. I believe that Tesla Motors wants to end the trend of Tesla Owners buying the highest capacity battery pack at the highest rate. It would be really nice if at least one version of the Model ☰ offers an initial range of 320-to-360 miles or so.

 

[Red Sage]

The other tidbit to note is with the new architecture, there is a new pack cooling setup compared to the current packs.

I'm hoping that a Model 3 75kWh pack is more efficient on its own, compared to current packs.

Because when you put pack efficiency gains, the weight loss from an S to a 3, and the aerodynamic improvements made, we're probably looking at close to 15% more range.....assuming the Model 3 75D can get close to or over 300 miles, compared to the Model S 75D's 259.

That's pretty damn impressive in such a (relatively) short amount of time.

If one presumes that compounded improvements in efficiency work together in a linear fashion... Then a range comparison between a Model S at a given battery pack capacity and drivetrain configuration and a similar design of Model ☰ might yield interesting results. That is, if you take the range of a Model S, divide it by five, and multiply the result by six, that can give you a general ballpark figure of what the Model ☰ might achieve:

__S _____☰ ___ Configuration
218 ___ 262 ___ 60D
259 ___ 311 ___ 75D
294 ___ 353 ___ 90D
270 ___ 324 ___ P90D

Though really, I think that is a bit off, and rather high. Because the Wh per mile expended would seem ridiculously low in each case. I'm thinking the actual ranges would be around 10% lower at best. In which case, only the Model ☰ 90D would get over 300 miles range.

 

[Incredulocious]

The Model S 40 weighed about 400 lbs more than the Toyota RAV4 EV, but still had a greater range by 36 miles..

This is just an aside to your argument about the impact of weight, but.... the RAV4 EV 's EPA range estimate wasn't actually tested (just roughly calculated) and it was adjusted down due to the normal vs. extended charge modes. In reality, you get over the official 103 mile EPA number for a normal charge and significantly more with extended charge (like 130 miles and up, when new). Here's a set of charts for highway usage:
Toyota Rav4 EV Forum • View topic - Range Chart

As a RAV4 EV owner, it's a little sad to see that 103 EPA number used widely when it's easy to do 120+ miles at 70 mph even after 25K miles, but that's the only official number we have. Would've been interesting to know what the true EPA tested number would have been. It also would be interesting to know what the CdA (drag x area) came out to. (Keep in mind that the RAV4 EV had one of the lowest drag coefficients for SUV's at 0.30, but I can't find a frontal area figure for it.)

RAV4 EV: CdA = 0.30 * ?? = ?? m2
Model X: CdA = 0.24 * 2.59 m2 = 0.622 m2
Model S: CdA = 0.24 * 2.34 m2 = 0.562 m2

Here's Toyota's video about improving air drag on the RAV4 EV:

 

[jkk_]

Tesla is in the process of proving 200 miles works well.

It doesn't for me.

I am not sure that a larger battery will even be an option.

So only one battery size for the 3? So Tesla doesn't want to sell the cars after all then?

 

[Dwdnjck]

I have 46000 miles in a model S 60. I know that a car with 200 miles of range can work, quite well, for most people.

 

[jkk_]

I have 46000 miles in a model S 60. I know that a car with 200 miles of range can work, quite well, for most people.

Which is why I said it doesn't work for me.

 

[modamoda]

That's a few generations of battery pack away.

Initial production, though? I no longer think a 75 is out of the question.

I would guess Tesla's battery capacity design is based on SpC network.
That means, 50% of "actual"(including software-locked area) battery should cover distance between SpCs = 120mi
And that's current MS/MX with smallest battery(75kWh).

So I think largest-battery-M3 would cover 240 mile(interval between 3 SpCs) distance with 50% charging. (am I thinking too radical?)

 

[jkk_]

I would guess Tesla's battery capacity design is based on SpC network.
That means, 50% of "actual"(including software-locked area) battery should cover distance between SpCs = 120mi
And that's current MS/MX with smallest battery(75kWh).

So I think largest-battery-M3 would cover 240 mile(interval between 3 SpCs) distance with 50% charging. (am I thinking too radical?)

I didn't quite understand your post, do you mean that largest battery option with the 3 would cover 480 miles with a full charged battery? As much as I'd like that, I don't think that's possible with the timeline that's current in play.

 

[lklundin]

We do need to remember that improvements in nearly all the energy usage factors (e.g. inverters, circuitry, vehicle control, battery management, heating and cooling, lighting) will yield very substantial improvements to effective range. Motors may see some improvement too, probably less significant, but if DC motors can be made to be practical, the improvements even there may be notable.

In other words kilowatt-hours is not the whole story, albeit it is one of the most important parts of the story.

Excuse me, but the efficiency of the different parts you mention are already around 90% or better, so any improvement there will be negligible compared to an annual improvement rate of 7%. You cannot double the capacity of something every 10 years, when it is already at 90% of its theoretical limit.

This is the reason why Elon Musk talks about the importance of the machine that builds the machine:

For a given effort you can only achieve tiny improvements in the components you mention, but get significant improvements in the manufacturing efficiency, which is the key to knocking down the price, for the whole vehicle and for the battery.

 

[googlepeakoil]

My first computer in 1990 had 4MB memory. Everybody told me it's totally foolish to buy such a huge computer
I think in 20 years we will laugh about a car with poor 75 kwh

Except JB has said batteries are improving at an aprox 5% a year - while CPU (and ram density) was doubling every 18 months. There was a big jump with the move to lithium - but there's only incremental improvements. I'd bet money that in a decade battery density won't have even doubled. You might see 50% - but remember lithium technology has been around 30 years. My first Sony camcorder had a tiny lightweight lithium battery that could run the digital-8 tape for 2-3 hours. I'd be surprised if Panasonic / Tesla make even a 20% improvement on density with going to their 2170 (they're not calling it 21700). Nissan Leaf + Volt -> Bolt are making huge improvements because their format was very low density compared with Tesla's 18650.
75kwh is a huge amount of electricity - enough to power the electrical appliances in my house for 1-2 weeks. You could run a 100w 60 inch tv for 750 hours! These aren't small amounts of electricity currently.

 

[porc]

Tesla projection of 8% improvement in energy density per year is too optimistic. Historically battery energy density improvements per year have been frustratingly small. Thats why your computer never has enough juice.

Any comparison with the computer industry shows a complete lack of perspective. We are not talking about the extrodinary improvements that have been achieved in the hardware of computers. Batteries are a totally different animal.


3% per year is the historical rate of improvement. Thus Red Sages projections are much too optimistic and ignore the historical rate completley.

 

[WarpedOne]

Excuse me, but the efficiency of the different parts you mention are already around 90% or better, so any improvement there will be negligible compared to an annual improvement rate of 7%.

This is true as long as one only looks at one part at a time, but the whole drive train consists of many ~90% efficient parts, connected in series:
- extraction of energy out of the battery: 10% goes into heating the battery, 90% to the controler
- inverter: 10% goes into heating the inverter, 90% to the motor
- motor: 10% goes into heating the stator and rotor, 90% goes into rotation
- reduction gears and differential: 2% goes into heat, 98% into torque on the output shafts
- half-shaft and wheel bearings: 2% goes into heat, 98% goes "through"
- brake-drag: 2% goes into heat, 98% goes "through"
- tire-drag: 10% goes into heat, 90% goes "through"
- auxiliary systems: 10% goes into heat, 90% goes into useful work

Feel free to replace efficiencies of parts with more accurate numbers.
Above chain of very efficient parts results in 55% overall efficiency. Replace all parts with others that have only half the losses and overall efficiency rises to 75% - one third improvement of range with same battery capacity, say 300 miles instead of just 220.
Efficiency is "system metrics".