Rivian is doing itself a disservice by not publishing a charging curve

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It takes two to tango. People in this thread are forgetting the inconsistent nature of charging speeds, especially with Electrify America. One location may be pushing consistent and fast speeds, while another be very, very slow. You just never know.

For instance, this past summer tried to drive from Denver to Kansas City, and Electrify America had throttled the charging speeds in Flagler, CO, Colby, KS, Hays, KS, and Salina, KS, since those locations are super low use. The 350kW units were only pushing 35kW or 36kW. It does not matter what the charging curve of the vehicle is when the charging location is facing challenges. It does not matter what the vehicle's charging curve is if two of the charging stations are down, and the other two are being used by super slow charging Chevy Bolts.

A Rivian charging curve is a "nice to know," but there will be many other factors that affect real charging speeds. I have used 40 different Electrify America chargers in 11 states. The only consistency amongst them is that there is no consistency. This is the lesson to learn with electric vehicles, especially ones depended on Electrify America for long distance driving.

That is part of the adventure of CCS compatible EV's - the unknown. Just be prepared for all scenarios, and have a back up plan. Hell, I remember driving between Denver and Las Vegas before the Electrify America locations were open in Salina, UT and Green River, UT, and I was in a 2019 Audi e-Tron with 200 miles of range. You had to go 150 miles out of your way to use a CCS charger while heading east, and then you had to hope a slow charging Chevy Bolt was not hogging the 50kW charger in Moab on the way back. It did not matter that the e-Tron has a generous 150kW charging speed to 80%.

I am not trying to lecture, or preach, but don't be too critical of Rivian for not providing full details on charging curves since they all too well know that there are lots of factors out of their control when it comes to charging a vehicle, especially for long distance EV driving dependent on an inconsistent network like Electrify America.
That's part of the reason I think a charging curve is handy to have (at least for me). If you know the battery is warm and you plug in and pull that 36kW you mentioned at 50% SOC, how else do you know if it's reasonable to expect that from the truck at that SOC, or if you should unplug and try and different charger? Or move on to a different station entirely?

I don't take your input here as lecturing at all. I actually think we're generally on the same page.
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That's part of the reason I think a charging curve is handy to have (at least for me). If you know the battery is warm and you plug in and pull that 36kW you mentioned at 50% SOC, how else do you know if it's reasonable to expect that from the truck at that SOC, or if you should unplug and try and different charger? Or move on to a different station entirely?

I don't take your input here as lecturing at all. I actually think we're generally on the same page.

We are on the same page, and I think we will eventually get a charging curve out of Rivian, or learn more about charging speeds for both vehicles as time goes on.

It feels like it may be too early for Rivian to feel comfortable to release this type of data since they may still be working on software, or don't feel comfortable since the current charging infrastructure is inconsistent.

If we think that Rivian has a max charging rate of 200kW and you arrive at an Electrify America charging location on I-80 in the middle of Nevada or I-70 in the middle of Kansas that is only pushing 40kW or 50kW for some reason, there is no other option for another station, you just have to charge slowly before you can continue your trip. That is the nature of the charging infrastructure currently.

Getting back to your point, yes, a charging curve is helpful. But, a charging curve will not always determine how a charging session will go. Especially with Electrify America.
 

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Just wanted to drop in my 2 cents. I have a reservation but won't buy unless I know what the charging curve is like.
. Why do you care what the actual curve is? What you really want to know is the overall average charging rate. You can be sure that it's going to be 1C or better as long as you stay out of the < 10% and > 80% bands. This means that you will be able to go from 10% charge to 80% in 42 minutes or less (provided, of course, that the charger is capable of more than 130 kW).

I have an older EV now, and it is great road trip car except for the slow charging curve.
Rivian's web site description of its DCFC charging suggests 1.32C. Clearly that would be under ideal conditions but implies 10 - 80% in 32 minutes. Suppose you realized 1.0C at a charger. Does 10 minutes mean that much to you?
 

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Charging curve is not some click bait topic, but rather, it is the most important fact BEV owners need to understand and educate themselves about charging instead of focusing on peak charging rate.
BEVs rarely achieve its peaking charging rate and when it did, it would be under ideal conditions (warm temperature, A perfect BMS, fully functioning DCFC, preconditioned/warmed battery), and that too for a brief period of its charging time.

Here are two videos that highlight the importance of charging curve VS peak charging rate.

1. Here is one with the eTron charging test at -10C.
This video shows how the eTron can maintain a flat 150KW rate all the way up to 80%,
Audi E-Tron 55 10-80% SOC Charging Speed & Time Test! - YouTube

2. Here is one where the charging rate of 4 EVs are compared (eTron Gt, Taycan, eTron 55 and Model 3).
You can see despite two vehicles having an 800V system (eTron GT and Taycan), the eTron 55 which has a flatter charging curve finished first to 90%.
Audi e-tron GT charging on 350 kW Ionity - YouTube

If anyone wants to learn about charging curve and charging rates, I highly recommend watching these two YT channels along with Inside EVs charging test videos to understand charging curves..
So what I see here is pretty much everyone does 10-90% in an hour. So does my 5 year old Tesla!
So do you expect Rivian to do better?

I think the Etron is a little bit quicker in that their 90% is more like 85% because of the top end reserve.
 
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So what I see here is pretty much everyone does 10-90% in an hour. So does my 5 year old Tesla!
So do you expect Rivian to do better?

I think the Etron is a little bit quicker in that their 90% is more like 85% because of the top end reserve.
The question is what the actual curve looks like in the 0 to 80ish percent range. Does it take 30 minutes to charge from 10 to 80% in ideal conditions? Is it 45 minutes? Do you have to plug in at 10% to get the 140 miles in 20 minutes? Is the curve fairly flat like the original etron curve, and it's pulling like 170kw near 80%? Or does it linearly drop from 200kw @ ~25% and then it only charging at... idk 75kw near 80%? Is the curve some time-based shenanigans like the Mach e (this is actually the one thing I'm worried about, lol)? And separately, what's it do north of 80%? Some cars are *extremely slow from 80 to 90% and then from 90 to 100%. Some are a little faster.

speaking of 10 to 90% (if that's the spec you care about), this video shows an interesting comparison between a few cars:
EQS: 40 minutes
E-tron GT: 33 minutes
Model S (93 kwh): 49 minutes
Mach e: much much more than an hour because Ford initially limited it to level 2 speeds above 80%.

As @ajdelange has pointed out many times, 1C or a little slower for the fully battery is pretty typical. But some EVs *really* suck to get from 90 to 100%. And the Mach-e is a total disaster above 80% (for now).
 

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So what I see here is pretty much everyone does 10-90% in an hour. So does my 5 year old Tesla!
So do you expect Rivian to do better?

I think the Etron is a little bit quicker in that their 90% is more like 85% because of the top end reserve.
This is a long post !

Charging curve's importance is not about total charge time or charge rate, at least it is not the primary reason for wanting to know it. Charging curve is all about understanding the charging characteristics of EVs, and all of them have their own characteristics, based on how the BMS is configured. And since we won't know how a BMS is configured, the charging curve is the best information to understand it.

By knowing the charge curve, you get a better idea on what SOC an EV will charge at its maximum charging capability, how long it can charge at that rate, or how much of a drop off it will experience once it reaches a certain SOC, or how slowly it will charge once it reaches 80, 90 or get close to 100%. There are EVs that prefer DCFC'ing at a lower SOC, some prefer charging at around 20% to obtain the peak charging rates. Some can maintain a peak rate for 10%, 20% or in the case of the eTron can maintain the peak rate all the way to 80% (The only EV I know of that can do this)

Here is a video demonstrating the Model S Plaid charging curve test,
Tesla Model S Plaid V3 Supercharging Complete Recording And Analysis - YouTube
Based on this video knowing what the charging curve of the Model S Plaid is, you can better plan road trips and what percentage you would want to charge when doing a road trip. Also, you would not need to wait for the car to fully charge.

In this video Kyle makes a mention as to why you need to pay attention to the charging curve, while explaining the Model S plaid charging curve,
Tesla Model S Plaid Charging Curve Test From 0-100%! - YouTube

Here is a little graph which shows how two Model S differ in their respective charging curves,
tesla-model-s-plaid-charging-1638896449.png

Source: The Tesla Model S Plaid Is the Quickest-Charging EV We've Tested (caranddriver.com)

Understanding charging curves for new EVs is more important than for something like a Tesla, because while they are learning, adapting, and hopefully improving their BMS to improve the charging capability, they are going to be far more conservative in the way they enable DCFcharging for their vehicles, to protect the battery pack.

This was the case with the Polestar 2 when it was first released. It had a bad charging curve, where despite having a peak charging rate of 150KW, no one even in ideal conditions were getting it. After multiple upgrades, and the most recent one where battery preconditioning was enabled when navigating to a DCFC, the charging curve was significantly upgraded.

This is why it is important to understand the Charging curve for Rivian, and how it handles different climate conditions as well as how it handles battery preconditioning when you have to charge. We have seen snippets of data, where people have shown pictures of charging rates of 30KW, 50KW, 100KW, 175KW. But this information needs to be put into context in the form of a charging curve to have a realistic expectation about the charging capability of the Rivian.

If not, that is when we will start seeing threads like, I was only getting X amount of charge when I plugged my vehicle, or why am I only getting Y amount of charging rate at this SOC when the vehicles are rated for this peak rate, and so on, which we will eventually see in this forum.
 
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If not, that is when we will start seeing threads like, I was only getting X amount of charge when I plugged my vehicle, or why am I only getting Y amount of charging rate at this SOC when the vehicles are rated for this peak rate, and so on, which we will eventually see in this forum.
Exactly. A *ton* of these threads popped up in December on the ID.4 forums and groups. Knowing what the ID.4 curve looks like, really helped with being able to say "well that's not normal" and then identifying that it was related to the cold (thanks to people with ODB plugs...)
 

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This is why it is important to understand the Charging curve for Rivian, and how it handles different climate conditions as well as how it handles battery preconditioning when you have to charge. We have seen snippets of data, where people have shown pictures of charging rates of 30KW, 50KW, 100KW, 175KW. But this information needs to be put into context in the form of a charging curve to have a realistic expectation about the charging capability of the Rivian.


I think this makes total sense, but we also need to understand where Rivian is currently. What are there, 50 or 100 R1T's on the road currently? Rivian also just issued an update this week, so they are still figuring things out about the car and making tweaks.

We will have more clarity on charing capabilities in a the months to come. Hell, most people will not have their hands on a their own vehicle for a year or more.
 

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Assuming the worst lessens the blow. always.
 
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This is why it is important to understand the Charging curve for Rivian, and how it handles different climate conditions as well as how it handles battery preconditioning when you have to charge. We have seen snippets of data, where people have shown pictures of charging rates of 30KW, 50KW, 100KW, 175KW. But this information needs to be put into context in the form of a charging curve to have a realistic expectation about the charging capability of the Rivian.


I think this makes total sense, but we also need to understand where Rivian is currently. What are there, 50 or 100 R1T's on the road currently? Rivian also just issued an update this week, so they are still figuring things out about the car and making tweaks.

We will have more clarity on charing capabilities in a the months to come. Hell, most people will not have their hands on a their own vehicle for a year or more.
Closer to about a 1,000 than 100.

The "early" factor here isn't any different than Hyundai showing the Ioniq 5's several months before it was released. That was an entirely new platform.

The curve will likely change (hopefully improve), but I think people are looking for some initial reference curve as a starting point.
 
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