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

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The smaller motor is more efficient due to a different rapport in the reductor, the car adapt the power between the two motors based on torque/speed, it's not that the smaller motor is more efficient
Wrong.
One small motor outputting 20kW has more losses than one big motor outputting same 20kW.
Small motor has less/thinner wires, resulting in higher resistance and more losses.
Big motor has more/fatter wires with less resistance and hence less losses.

Basics.
 
Wrong.
One small motor outputting 20kW has more losses than one big motor outputting same 20kW.
Small motor has less/thinner wires, resulting in higher resistance and more losses.
Big motor has more/fatter wires with less resistance and hence less losses.

Basics.
We have to call Tesla that they're doing it wrong!
Who can explain to me how the front motor in the D gets to do the most work?

Also, I was very much correct in stating that Tesla's motors are sized to take the last WATT from the battery pack. A Lego motor could take the last kWh out.
If you're going to be a smartypants, then get it right.
 
We have to call Tesla that they're doing it wrong!
Who can explain to me how the front motor in the D gets to do the most work?

Also, I was very much correct in stating that Tesla's motors are sized to take the last WATT from the battery pack. A Lego motor could take the last kWh out.
If you're going to be a smartypants, then get it right.
The PD actually got less range than the equivalent P (back when they offered a RWD P). The non-P D have the same size motor front and rear. They are just geared differently.
I am not sure if anyone has found a way to disable the rear motor in a PD to determine how much range would be gained with only one small motor.
 
We have to call Tesla that they're doing it wrong!
Who can explain to me how the front motor in the D gets to do the most work?

Also, I was very much correct in stating that Tesla's motors are sized to take the last WATT from the battery pack. A Lego motor could take the last kWh out.
If you're going to be a smartypants, then get it right.
You were referring to a comment about the size of a single motor and efficiency of a large motor (high power) vs a small motor (low power) with a comment about dual motors... That doesn't make sense.

Also a Watt is a measure of power whereas a kWh is a measure of energy.
 
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Just to be a bit pedantic - when he is referring to the last Watt, the correct correction would be "the last Watt hour" or "the last Wh". No reason to multiply it by 1000 :)
I was sticking to the poster's original units and since he was referring to sizing a motor for a specific task, he was referring to power so watt-hour is not a good correction. The correction would be to remove the lego sentence altogether as it made no sense in the context of the comment he was referring to (which was about power output)
 
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We have to call Tesla that they're doing it wrong!
Engineers at tesla know what they are doing.
People on the internets not so much.

Who can explain to me how the front motor in the D gets to do the most work?
By setting appropriate voltage levels at the motor terminals.

Also, I was very much correct in stating that Tesla's motors are sized to take the last WATT from the battery pack. A Lego motor could take the last kWh out.
Every motor can take the last WATT, even lego motor.
What it does with this watt is another matter.

If you're going to be a smartypants, then get it right.
Indeed, start with learning the basics of electric principles and forget about the truths of ICE world. They do not directly translate to electric world.
Size of electric motor tells you nothing about its efficiency per see.
When two differently sized electric motors built with same technology are outputting the same power then a bigger motor will have lower losses.
 
I believe if Elon and JB are the innovators in new battery useage... at least new in cars, they will go with
SOMETHING ENTIRELY DIFFERENT. The current battery tech requires layering for cooling purposes, etc.
That drastically limits what it can do. I'm just wondering how closely they are following LIQUID BATTERIES for a lack of a better word.
Plus, they are also far less apt to crack, overheat, etc, as they are pliable. Here's an interesting link if you're not aware.
MIT's new liquid battery charges with gravity - like an hourglass

Here are two of the more interesting paragraphs toward the end of the article (past the ads)

Yet-Ming Chiang, professor at MIT and co-founder of 24M, was inspired to pursue a new manufacturing method after noting inefficiencies in the status quo. “We’re reinventing the lithium ion battery,” says Chiang, “the cost of the product is too high, and the manufacturing process is too complex.” After decades of little change in how lithium batteries were produced, Chiang and his team have developed a new process that allows for a radical decrease in battery costs and increase in durability.

The new process uses fewer, thicker electrodes than in traditional lithium batteries, which allows for a simpler, more efficient battery structure. This method reduces the amount of non-functional material in the battery structure by 80% and produces lithium batteries that can be folded, bent, or punctured by bullets without failing. The capital investment for building and expanding a factory with 24M’s new process is also significantly less than traditional lithium battery manufacturing.

I WISH 24M WAS NOT A PRIVATE COMPANY... as I would buy stock, as I did Tesla a few years ago.
 
I believe if Elon and JB are the innovators in new battery useage... at least new in cars, they will go with
SOMETHING ENTIRELY DIFFERENT. The current battery tech requires layering for cooling purposes, etc.
That drastically limits what it can do. I'm just wondering how closely they are following LIQUID BATTERIES for a lack of a better word.
Plus, they are also far less apt to crack, overheat, etc, as they are pliable. Here's an interesting link if you're not aware.
MIT's new liquid battery charges with gravity - like an hourglass
Flow batteries for cars? There's been a lot of talk and a lot of prototypes but I've never heard of one making it to production or being affordable.
 
Flow batteries for cars? There's been a lot of talk and a lot of prototypes but I've never heard of one making it to production or being affordable.

yea, I know, so I'm wondering why wouldn't they be thinking about it, as it erases MANY of the concerns of conventional batteries.
With FEWER parts and (apparently less expensive, due to complications), I would think that's the next leap, not how many layers and crap you can jam into a current battery, module and pack. :)
 
yea, I know, so I'm wondering why wouldn't they be thinking about it, as it erases MANY of the concerns of conventional batteries.
With FEWER parts and (apparently less expensive, due to complications), I would think that's the next leap, not how many layers and crap you can jam into a current battery, module and pack. :)

Fewer moving parts? Conventional lithium batteries have no moving parts (besides at the atomic level). Flow batteries are expensive and a heck of a lot can go wrong. I highly doubt we'll ever see flow batteries in a production vehicle. I'm not even sure what happened to this: 900hp Quant EV powered by flow cell battery

Using flow batteries for stationary utility energy storage is a whole other beast.
 
Wait...hold on..did I read that graphic correctly?

A 25% REDUCTION IN COST? Wait what? Are you kidding me? That's the same thing Tesla said. Well fancy that.

Wait again..... with room for improvement with changes in chemistry.... I have to sit down. I'm getting light headed.

I was starting to believe all of the battery haters in this forum.

Tesla can't.....ABC .... It will never fit
Tesla can't .....DEF..... It will cost too much
Tesla can't.....GHI......They haven't put it in the MS yet.
Tesla can't......JKL.....There isn't enough room.....
Tesla can't......MNO....That's why the starting price for the M3 will be a million dollars...
whine, whine, whine.


View attachment 191827

You keep confusing the different energy densities. In a purpose built BEV, specific energy or gravimetric energy density is the limiting factor. It's not volumetric energy density nor power density. This is mainly because there is enough battery capacity that power density is not a factor, and a purpose built BEV has enough space for a large amount of battery. The limitation becomes, first, specific energy.

Since 2012, there has been specifically one chemistry change in Tesla's cells that has brought higher specific energy. There have been two pack level changes, the first I don't know if it changed specific energy, and presumably this last change with the 100 kWh pack, there was a also a change.

That's it. There's no magic here... you can follow the ARPA-E and DoE research and see where the battery chemistry is going. Since the Model 3 is shipping next year, there is no time for much change in chemistry. At this point, the chemistry should already be well known in order for it to make it into production. What we don't know is the precise amount of silicon they managed to put into anode in order to boost specific energy. They have to balance cycle life - that has been the big limiting factor.
 
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Fewer moving parts? Conventional lithium batteries have no moving parts (besides at the atomic level). Flow batteries are expensive and a heck of a lot can go wrong. I highly doubt we'll ever see flow batteries in a production vehicle. I'm not even sure what happened to this: 900hp Quant EV powered by flow cell battery

Using flow batteries for stationary utility energy storage is a whole other beast.

You're correct, I shouldn't have said "moving parts." But fewer parts (layers) that are required with Cathode/Anode style batteries.

63477-fig1.jpg
 
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