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Ronaldinho

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If I recall, the 58 series battery is 5600mah and the 50 series is 4800mah. But I could have sworn there was something in between. And 100% yes to more severe degradation with higher capacity cells. This could certainly be a short term gain / long term loss for Rivian. And if that is the case, I'm pretty disappointed.
There's a 53G version of that Samsung cell.

This link also turned up when I was looking for more info on that cell: https://www.batterydesign.net/rivian-max-battery-pack/
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If I recall, the 58 series battery is 5600mah and the 50 series is 4800mah. But I could have sworn there was something in between. And 100% yes to more severe degradation with higher capacity cells. This could certainly be a short term gain / long term loss for Rivian. And if that is the case, I'm pretty disappointed.
Could you and @GhostAndSkater please elaborate on why higher capacity cells degrade more quickly? I’ve Googled it, but no results.
 

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On Munro teardown you can clearly see the Large Pack uses Samsung INR21700-50G cells, each is 17.787 Wh, with 7776 cells, the large pack is 138.31 kWh gross

If they use LG INR21700-M58T the Max Pack, each is 20.4 Wh, resulting in 158.63 kWh, a 10 kWh buffer seems way too big for a 149 kWh pack,
There is one thing that everyone is completely overlooking. Is that 7777th cell in the Rivian Torch also using the new chemistry? :CWL:
 

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Could you and @GhostAndSkater please elaborate on why higher capacity cells degrade more quickly? I’ve Googled it, but no results.
Sure, first, I'm not battery expert, but work with them and designed and tested my fair share of packs on my career so far, so anyone feel free to correct me

There is a few things you need to balance, electrode and current collector thickness (by the way, this is one of the places the tabless electrode from Tesla shines, you don't need to compromise much on either, I digress)

Current collector are the metal foils of copper and aluminum that the anode and cathode are deposited, those will be wound into the jelly roll that is stuffed inside the cylindrical cell can

If you want a higher power cell, you need to have thicker current collectors, which takes more space, and more porous anode and cathode to the lithium ions can flow quicker in either direction

For high energy density it's the opposite, you might use thinner current collectors and more dense anode and cathode, less porous, the cell inside literally has more active material

Another way is to make the anode and cathode material thicker so you need less turn to make the jelly roll

Both of these make it more difficult for the Lithium ions to flow, and if forced to flow faster you might degrade the cell

Why? First SEI growth, still on the factory the solid electrolyte interface is created, it's (so far) an unavoidable and normal process that consumes lithium and forms a protective coating, but due to all the points above, in a high energy cell pushed hard, it can grow faster than expected and result in accelerated degradation because less lithium is available

Second, Lithium plating, since the ions can't get inside the cathode or anode, they form a metallic lithium layer that results is less lithium being available to store energy, and if this gets bad enough, a internal short occur, which can either just result in self discharge, or a full blown fire, this is why it's important to have a really good BMS that avoids conditions where it might occur

Highly recommend this (all other videos from this channel) for anyone interested on everything batteries

 

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Could you and @GhostAndSkater please elaborate on why higher capacity cells degrade more quickly? I’ve Googled it, but no results.
@GhostAndSkater did a fantastic job explaining that. And I will add that a great real-world example is the degradation difference between the Model S 85kwh and 90kwh battery packs. The 90 is far steeper of a curve and more extreme energy loss compared to the 85. Same type of changes as Rivian, higher capacity cell.

They’ll tell you it applies to everyone but Tesla’s batteries

?
Especially Tesla batteries as sighted above.
 

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I'm just going to come right out and say it. Rivian needs to nix the max pack completely. Maybe throw in the 5200ah "max" pack cells into the large pack but then continue to derate the usable. The end result is a slight bump to range, but virtually zero degradation to the owner since the buffer can be eaten away as the battery ages. Imagine advertising, "the first EV to market where your capacity is guaranteed for X years, never worry about degradation again!"
 

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I was told they are using a 5200ah cell, by someone who knows a lot about batteries inside EVs. Is that what the 53 series is?
Could be. But I believe LG has a 21700 M52 cell that could be the one as well.

At this point it still feels like we're throwing darts while blind folded.
 

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No groundbreaking information in this video, but it's the first media I've seen covering real world experience with the max pack.

 

Supratachophobia

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Could be. But I believe LG has a 21700 M52 cell that could be the one as well.

At this point it still feels like we're throwing darts while blind folded.
Ugh, I know. I keep coming back to the problem of paying $7k for 10kwh of battery. Everyone says the range is the thing to remember, but I've yet to see believable attempts at getting said range or explaining the other efficiency improvements that get you there. It just doesn't add up with the existing information.
 

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I'm just going to come right out and say it. Rivian needs to nix the max pack completely. Maybe throw in the 5200ah "max" pack cells into the large pack but then continue to derate the usable. The end result is a slight bump to range, but virtually zero degradation to the owner since the buffer can be eaten away as the battery ages. Imagine advertising, "the first EV to market where your capacity is guaranteed for X years, never worry about degradation again!"
No. I want as much range as possible.

But I do agree a battery that degrades faster is not a good thing. My Mustang Mach-e (MME) is two years old, and the battery state of health is 93%. That does not make me happy at all. But it could be worse, and as time passes, it will get worse.

I originally wanted what Rivian originally promised: quad motors, 180 kWh battery pack and a removable roof. I was so excited about that. Now, we have what? Not that.

The R1 is still on my short list for replacing my MME, but range is main reason now. If they can't do that well, I may have to get a Lucid Gravity. Assuming it doesn't cost $150k, which it might. I am not paying $150k for a car, even if my wife would let me.

Wait a minute, there is the Cybertruck to consider...

:CWL:
 

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Sure, first, I'm not battery expert, but work with them and designed and tested my fair share of packs on my career so far, so anyone feel free to correct me

There is a few things you need to balance, electrode and current collector thickness (by the way, this is one of the places the tabless electrode from Tesla shines, you don't need to compromise much on either, I digress)

Current collector are the metal foils of copper and aluminum that the anode and cathode are deposited, those will be wound into the jelly roll that is stuffed inside the cylindrical cell can

If you want a higher power cell, you need to have thicker current collectors, which takes more space, and more porous anode and cathode to the lithium ions can flow quicker in either direction

For high energy density it's the opposite, you might use thinner current collectors and more dense anode and cathode, less porous, the cell inside literally has more active material

Another way is to make the anode and cathode material thicker so you need less turn to make the jelly roll

Both of these make it more difficult for the Lithium ions to flow, and if forced to flow faster you might degrade the cell

Why? First SEI growth, still on the factory the solid electrolyte interface is created, it's (so far) an unavoidable and normal process that consumes lithium and forms a protective coating, but due to all the points above, in a high energy cell pushed hard, it can grow faster than expected and result in accelerated degradation because less lithium is available

Second, Lithium plating, since the ions can't get inside the cathode or anode, they form a metallic lithium layer that results is less lithium being available to store energy, and if this gets bad enough, a internal short occur, which can either just result in self discharge, or a full blown fire, this is why it's important to have a really good BMS that avoids conditions where it might occur

Highly recommend this (all other videos from this channel) for anyone interested on everything batteries

Would the degradation be worse if the max pack battery was used with the quad motor, because the quads can pull more max power/current?

I'm wondering if this is one of the reasons they don't do the max pack battery with the quad motor.
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