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"BEV3 will be a fully modular battery pack and will have different configurations able to accommodate 6, 8, 10, 12 or 24 packs of cells."

We could get different vehicle range based on "trims". Interesting!
 

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Modular and "change out" units have a problem - making sure the liquid cooling system stays intact. Otherwise, you get leaks, overheating, and fires...
 

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Good read.
Drauch says the battery state estimator “is one of the most important pieces of code we have in the car,” and because you “can’t just go out and buy a battery state of charge estimator,” from a supplier, the automaker must develop its own software for doing so.
I'm really pleased with the Bolt's "Guess-O-Meter". I find it to be quite accurate in constant driving conditions, and here in the hilly terrain around Vancouver I really like the "Min" and "Max" estimates and especially the trend indicator - all that information really helps when I'm on a long trip.
 

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Modular and "change out" units have a problem - making sure the liquid cooling system stays intact. Otherwise, you get leaks, overheating, and fires...
Modular in terms of packs of cells doesn't = change out units... it just means one car can have 12 and a different car 24 of identical easily mass producible pack units. I envision this more like the Tesla battery packs in the older cars that each have 16 identical bricks of cells... in a smaller GM car you use a pack case with 12 bricks, in a larger car you use a pack case with 24 bricks... still self contained and with minimal points of potential failure via leaks or other problems.

This is one of the beauties of the new Tesla system. With the new system used in the model 3 and Y each brick has the same number of cells weather you have the short range or the Long range... but the short range has some dummy bricks in the case instead of "real" bricks. Same battery case, same size bricks... but different capacity.

Later,

Keith
 

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This is one of the beauties of the new Tesla system. With the new system used in the model 3 and Y each brick has the same number of cells weather you have the short range or the Long range... but the short range has some dummy bricks in the case instead of "real" bricks. Same battery case, same size bricks... but different capacity.
The Model 3 uses the same box for all their battery packs. I have only seen teardowns of the long range pack, so can't say what the modules inside the lower range batteries look like. The long range battery has 96 individual cell groups made up of 46 individual cylindrical cells each. The cell groups are permanently glued, and spot welded into blocks of 23, and 25 cell groups each. There are 4 blocks total.

The Chevy Bolt has 96 individual cell groups made up of three pouch cells each. The cell groups are permanently glued, and spot welded into blocks of 18, and 20 cell groups each. There are 5 blocks total.
 

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Drauch says the battery state estimator “is one of the most important pieces of code we have in the car,” and because you “can’t just go out and buy a battery state of charge estimator,” from a supplier, the automaker must develop its own software for doing so.
I'm really pleased with the Bolt's "Guess-O-Meter". I find it to be quite accurate in constant driving conditions, and here in the hilly terrain around Vancouver I really like the "Min" and "Max" estimates and especially the trend indicator - all that information really helps when I'm on a long trip.
What's being talked about here is more primitive than the GOM. For the GOM to work, it needs an estimate of expected efficiency (miles/kWh) but also an estimate of battery capacity and present state of charge. I believe the quote is referring to these latter two. Just being able to say “the battery has 17% left” is hard, and having that mean that the car can expect to get 9.7 kWh out of the battery is yet harder. Beyond that, saying the car has 37 miles left is probably the easiest bit.
 

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The Model 3 uses the same box for all their battery packs. I have only seen teardowns of the long range pack, so can't say what the modules inside the lower range batteries look like. The long range battery has 96 individual cell groups made up of 46 individual cylindrical cells each. The cell groups are permanently glued, and spot welded into blocks of 23, and 25 cell groups each. There are 4 blocks total.

The Chevy Bolt has 96 individual cell groups made up of three pouch cells each. The cell groups are permanently glued, and spot welded into blocks of 18, and 20 cell groups each. There are 5 blocks total.

Shows a SR+ battery pack with the top cover removed showing two blocks with 25 cell groups and one block with 23 cell groups, and a dummy block replacing the other 23 cell group block giving you 73 cell groups (3,358 cells) instead of 96 cell groups (4,416 cells). This would give the SR+ 76% of the capacity of the LR.

Keith
 

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Shows a SR+ battery pack with the top cover removed showing two blocks with 25 cell groups and one block with 23 cell groups, and a dummy block replacing the other 23 cell group block giving you 73 cell groups (3,358 cells) instead of 96 cell groups (4,416 cells). This would give the SR+ 76% of the capacity of the LR.

Keith
Weird. I would love to know how that works, as 73 cells gives you a fully charged voltage of 300 volts. Not enough for the Model 3 to get out of its own way. Maybe the dummy block is a boost converter of some kind?
 

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Weird. I would love to know how that works, as 73 cells gives you a fully charged voltage of 300 volts. Not enough for the Model 3 to get out of its own way. Maybe the dummy block is a boost converter of some kind?
A depleted LR battery can't deliver meaningful current at 300 V, but a fully charge SR+ battery would be able to deliver full current at 300 V... For the SR+ max output of 250 KW at 300 V the battery would have to supply 833 amps of current. For the performance AWD with max output of 432 KW, at full pack voltage of 395 V the battery would have to supply 1093 amps.

Looks like the math works out to me :)

Later,

Keith

PS: Not saying that they did it this way, just that the math (power in KW = Voltage * current) works out.

PPS: You can't get a strait answer on power output for various Model 3's from the internet. Some say the SR+ has 211 KW, some say 250 KW, and some don't know the difference between the AWD LR and the AWD performance and mix up the power numbers... very frustrating!
 

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You can't get a strait answer on power output for various Model 3's from the internet.
Sure you can. Matt Schumacher has some great videos up on his Tesla channel.



He is a great guy. He has been building amazing electric bicycles since 2008. He was selling his drive systems until 2018, at least. Here is an example. Notice how easy it is to lift the frontend on a 12 kW electric bicycle? :)

 

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Sure you can. Matt Schumacher has some great videos up on his Tesla channel.



He is a great guy. He has been building amazing electric bicycles since 2008. He was selling his drive systems until 2018, at least. Here is an example. Notice how easy it is to lift the frontend on a 12 kW electric bicycle? :)

Thanks! I will check out his channel.

But with over the air updates that can change the power output of your model 3, even his information may be out of date soon :)

Keith
 

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What's being talked about here is more primitive than the GOM.
Yeah, I understand that. But the GOM is totally dependent on the ability of the vehicle to assess the state of charge of the battery. When I say that I like the GOM, I'm saying that they've done a good job of everything that's needed to support it.
 
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