SeaGeo

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At some point we'll re-do the test at that EVGo station, however the charge curve was oddly similar at one of the rare 350kW ChargePoint stations and a brand new EA station.
With the random spikes?

I'd definitely watch the dashboard I mentioned next time you do a deep fast charge. It clears up a lot of the questions.

The truck will definitely thermally derate at the moment, but so far I've had the fast charger derate off 500A first on new and old EA installations. Unfortunately i havent driven out to an EA Signet station to try yet. Basically, when the truck says it's the chargers fault it's not lying.

They need to improve preconditioning and increase the max temp before the truck derates at the moment. Precondtioning is often not successful, and their thermal limit for the battery is a fair amount lower than others while also kicking the cooling system on at the absolute last minute typically.

 
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With the random spikes?

I'd definitely watch the dashboard I mentioned next time you do a deep fast charge. It clears up a lot of the questions.

The truck will definitely thermally derate at the moment, but so far I've had the fast charger derate off 500A first on new and old EA installations. Unfortunately i havent driven out to an EA Signet station to try yet. Basically, when the truck says it's the chargers fault it's not lying.

They need to improve preconditioning and increase the max temp before the truck derates at the moment. Precondtioning is often not successful, and their thermal limit for the battery is a fair amount lower than others while also kicking the cooling system on at the absolute last minute typically.
Yes and oddly in around the same SOCs as well. I wish that Rivian would spend less time on peak rates and more time on improving the average, especially rates over 80% where Hyundai's eGMP packs are simply flying. With a truck seemingly focused on towing, where you really need that pack full, the R1T and Lightning take an eternity to get to 95-100%
 

Dark-Fx

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And why disable adaptive cruise control?
It might be a technical reason, but they use buttons on the steering wheel for trailer gain/control that were used for setting distance.

As far as trailer stability goes, the Rivian's stability control system intervenes early and often despite the Rivian having more lateral grip than an F-150 Lightning. This has the feel that the trailer is wagging the dog so to speak, but in reality it's simply the system's over-eager intervention at work. On down-hill winding roads with 9,100 pounds on the back, the accelerometer we use for testing picked up these interventions and they are quite noticeable vs a Lightning, or any 1/2 ton truck or even mid-size SUV that we have tested on the same stretch with the same trailer.
How much of this is "intervention" versus the fact that Rivian has individual wheel torque control?
 
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It might be a technical reason, but they use buttons on the steering wheel for trailer gain/control that were used for setting distance.

How much of this is "intervention" versus the fact that Rivian had individual wheel torque control?
On the steering wheel controls: they could always use the screen to adjust distance, or implement it some other way.

On the stability control: zero since it occurs in the Rivian power on / power off and even in neutral. It's the stability control which is performed with the ABS system as it is in pretty much everything out there.
 

NooterIA

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Lol, nit pick is an understatement. Doesn’t like the hitch position? Really? I’ve towed enough with mine now, wouldn’t change a thing other than the range impact.
 


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Lol, nit pick is an understatement. Doesn’t like the hitch position? Really? I’ve towed enough with mine now, wouldn’t change a thing other than the range impact.
Eh, I can see where he's coming from. The receiver is tucked pretty far back behind the bumper. Certainly more so than traditional trucks. A few people have posted about their existing hitches/racks not being long enough. There's also been some issues of pins being too short.

Not the end of the world... But it's a fair fact to point out.
 

SeaGeo

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Yes and oddly in around the same SOCs as well. I wish that Rivian would spend less time on peak rates and more time on improving the average, especially rates over 80% where Hyundai's eGMP packs are simply flying. With a truck seemingly focused on towing, where you really need that pack full, the R1T and Lightning take an eternity to get to 95-100%
That's very weird. I haven't seen that consistently happen on any of the trucks if you're seeing this occur on a "normal" charge starting from say 5 or 15%+. You may want to submit a service ticket tbh. For example, my truck requests 500A from a low SOC until it hits about 45C for the max pack temp. The chargers always drop below 500A first. I've never had the truck temporarily spike down like that, and haven't heard of anyone else having that issue either.

They need to (and I think will soon) adjust their cooling and temp management in the software to reliably hold close to that 500A from ~0 to 45 or 50%. Currently it's throttling when the max pack temp hits 45C, whereas other manufacturers let the packs hit between 55C and 65C from what I've seen. Pair that with not turning the compressor on early enough to prevent it from hitting 45C, and preconditioning not working consistently, and you have a recipe for consistent derating with deep chargers.

I totally agree about charging at a high SOC. Honestly charging above 70% with it annoys me, let alone 80%+. Some of that is it hits the constant pack voltage portion of the charging curve at around 50%, so it's ~linearly decreasing current after that. The end result is a curve that's it's fairly close to other large pack ~400v class vehicles. But practically speaking, I think a lot of it is them intentionally being very careful with the batteries to limit degradation. Same with Ford. It's going to be really interesting to see how the eGMP cars hold up.
 

 
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