Why do Rivians charge so slow?

[NineElectrics]

Unlike the e-tron, Rivian doesn’t have the tech. to significantly cool the battery at high state of charge. Therefore, DC charging at above 80% is painfully slow.

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[HighVoltOverland]

It seems incredibly disingenuous to try and compare the Rivian to all the egg shape efficiency chasers on the market

I wouldn’t complain that a F150 took longer at the pump than a fiat 500

 

[MoreTrout]

It's already been explained well, but let me rephrase the original post and question to try a common sense approach.

Recently I saw a Ford F150 ICE truck and a Ford Fusion ICE sedan pull into a gas pump. Both of them pumped 5 gallons of gas in their tank in identical times of 1 minute. The truck pumped "100 miles/min" and the Fusion pumped "200 miles/min". So something is obviously wrong with the truck, right????

No one would ever consider asking that question, yet they do the same thing all the time with EVs because they don't grasp the concept of kWh being what you are delivering as easily as they understand gallons for ICE vehicles.

 

[RivAW]

From a road tripping standpoint, miles per hour is apples to apples. Time to get to the next charging stop. I actually like the comparison of time to add 100 miles.

Yes, but be honest with yourself….the answer is that the vehicle is receiving the same amount of electricity at approximately the same speed, but due to “efficiency” of the vehicle it translates to less MPH for charging. That’s just physics….

 

[usulio]

It's not the worst thing that there are a variety of measures out there. Per Goodhart's law, if there was a single standard, companies would optimize the car specifically for it at the cost of overall performance.

On top of that, measuring charging performance is very complicated and context-dependent just like measuring range. I hope places like Edmunds can give an overall evaluation, not just one test.

As people have mentioned, it's also a problem that cars can get better charging by sacrificing long term health of the battery. And it will be very hard to tell for years. We don't want to get so obsessed over numbers comparisons that they start doing that.

 

[azbill]

Yes, but be honest with yourself….the answer is that the vehicle is receiving the same amount of electricity at approximately the same speed, but due to “efficiency” of the vehicle it translates to less MPH for charging. That’s just physics….

I understand physics, I have an EE degree. Let me provide my real world experience, since I have a Mach E and a Rivian. I have taken both on a few identical trips, and they both provide me with about 300 miles of highway range at 70-75mph. My Mach E is actually 50% more efficient than the Rivian, but charges slower (150kw peak versus 220kw peak). But both can provide me with 120-140 miles in 20 minutes. In the end I spend nearly the exact time at each charger to get to the next one. The fact that the Rivian has a higher kw charge rate does not provide me any benefit, but it costs me more $ to go the same number of miles.

I am measuring charge rate in terms of time, not in terms of power. Also, the Mach E actualy has a much flatter charge curve, so if I start charging at a higher SoC, let's say 40%, it out performs the Rivian in terms of MPH.

On road trips I try to plan on 20 minute stops and have found the shortest charge times occur if I stay within 15-60% SoC, which is normally the charging sweet spot. It is only when I absolutely need more range that I would go to 80% or more.

 

[Lawrence-of-Blaine]

I understand physics, I have an EE degree. Let me provide my real world experience, since I have a Mach E and a Rivian. I have taken both on a few identical trips, and they both provide me with about 300 miles of highway range at 70-75mph. My Mach E is actually 50% more efficient than the Rivian, but charges slower (150kw peak versus 220kw peak). But both can provide me with 120-140 miles in 20 minutes. In the end I spend nearly the exact time at each charger to get to the next one. The fact that the Rivian has a higher kw charge rate does not provide me any benefit, but it costs me more $ to go the same number of miles.

I am measuring charge rate in terms of time, not in terms of power. Also, the Mach E actualy has a much flatter charge curve, so if I start charging at a higher SoC, let's say 40%, it out performs the Rivian in terms of MPH.

On road trips I try to plan on 20 minute stops and have found the shortest charge times occur if I stay within 15-60% SoC, which is normally the charging sweet spot. It is only when I absolutely need more range that I would go to 80% or more.

Super useful stats. Thank you.

 

[SRO]

Larger battery and more power hungry truck makes for a slower charge rate when you use miles per hour. If you want to compare apples to apples on charging speed use kw and not miles per hour.

Kw is the same as kWhr/hr. My T charges at about 11.1 kWh/h or 11.1 kW for level 2. So I agree that is the way to compare vehicles with different battery sizes and efficiencies.

 

[Count Orlok]

The Count's F-150h takes longer to fill up that his 911.

 

[BeanEW]

It is only as fast as the weakest link.

 

[jebinc]

Recently I've noticed a study done by Edmunds. It rates EV's according to charging speed. The fastest was a Hyundai Ioniq 6 at 868 miles per hour. Rivian R1T was number 37 at 316 miles per hour. That's less than half as fast. That is a significant difference. Why is that? I'd like to point out that the rating number can depend on minor differences that you wouldn't think would affect charging, like tire size. 20- and 21-inch Rivians have separate ratings (37 and 38). If you eliminated these things, the list would be way shorter.

Want slooooow? Go look at the Cybertruck charging curves… ?

 

[Russya]

I do this math with my wife all the time because for her, all she cares about is how long she has to sit at the charger before she can leave to get home after work if she forgot to charge her car the night before. That being said…. I personally don’t like it because it promotes very narrow thinking and rewards poor product design.

Case in point. EV9. That vehicle in light long range trim which is what you need to get over that magical 300 mile range mark is RWD only and 201hp. That’s less power than a Chevy Bolt. It’s ridiculous. But it will look good on that chart and that’s all some people will see or care about. These types of metrics drive the automotive landscape to duller and duller products that are less capable. Slippery jelly bean boxes that aren’t any good anywhere outside of a freeway commute and honestly aren't that great there either(Efficiency wise). You can see the problem here.

Edmunds AWD SUV ranking

Notice it ranks it as best AWD SUV and then puts a range claim of 306 miles. The AWD can't do 306 miles, and as a downside they list how slow the base model is but leave out that the Long range RWD model is considerably slower. Yet we dont see the same thing done for Rivian. It should say for the R1S 835hp, 400miles of range, starting at $78k. All of those facts are true, but can't be combined into one vehicle.


Here's a good example of what this narrow thinking has done in a broader sense. Via Car and Driver.
1994 SUV's

Current SUV's

Are the new ones better at commuting? undoubtedly. Are they nearly as capable as being off-road capable SUV's as they were 20 years ago? Not a chance. We now have less capable vehicles, because people don't want to be honest with themselves that what they really need is a ford flex or minivan type vehicle and not an SUV and yet try to put metrics on them that they clearly were not designed to optimize. People should be buying the best tool for their needs and stop trying to make their screwdrivers into a chisels. We would have better commuter vehicles and better SUV's if they did. And when you have a charts like this, that's what you get. If you're honestly most worried about this metric and want an "SUV" then get Lucid Gravity. What I would hate to see is Rivian's become less and less capable like what happened to the VW Touareg. When launched had locking diff's amazing suspension, great off-road and on. Now, no locking diffs, normal suspension and isn't great anywhere.

As of right now, there is only two Electric SUV's made(R1S, Hummer). But there are a whole bunch of electric barely crossovers that are masquerading as SUV's. If you can't match a Subaru outback off-road... you're not an SUV, you're a crossover and your efficiency shouldn't be compared to vehicles that are. No rationale person would compare a Honda Ridgeline to a Ford Super Duty yet with Electric "SUV's" we put the Ioniq 5 and Mustang (Both of these are beyond laughable being called SUV's) in comparison to an R1S. Or as the original post did an Ioniq 6?

Long rant... I apologize.

 

[CharonPDX]

Recently I've noticed a study done by Edmunds. It rates EV's according to charging speed. The fastest was a Hyundai Ioniq 6 at 868 miles per hour. Rivian R1T was number 37 at 316 miles per hour. That's less than half as fast. That is a significant difference. Why is that? I'd like to point out that the rating number can depend on minor differences that you wouldn't think would affect charging, like tire size. 20- and 21-inch Rivians have separate ratings (37 and 38). If you eliminated these things, the list would be way shorter.

Because Rivians are large vehicles. They're inefficient. An Ioniq 6 is a super-efficient sedan. Compare the MPG of a Honda Civic to a Honda Ridgeline.

More efficiency means less "fuel" used per mile, which means less total energy needed to "refill." When you fully charge a Rivian, you're adding 125ish kWh. When you're fully charging an Ioniq 6, you're adding half as much.

Then add the fact that the Hyundais use an 800V architecture, which means it takes lower amperage to achieve the same power-flow-rate into the batteries, and higher amperage creates more heat, which causes less efficient charging. So even when both the Rivian and the Hyundai are getting 225 kW charge rate, more of that 225 kW is getting stored in the Hyundai's battery rather than getting lost as heat.

More efficient vehicle + more efficient charging = many more "miles of range" added per hour of charging.

 

[runwithscissors]

Public charging stinks at this point with EA. Road tripped a few hundred miles the other morning and was plagued by dead chargers and broken down cars in chargers. 4 chargers, 1 was dead, the other had a dead Ioniq 5 in it waiting on a tow truck. The other had a guy sleeping in it at 97%.

I kindly ask the guy in a different Ioniq 5 how long he's going to be and he's like oh about 15 minutes. He's like ya they give me free charging etc... So for now on I'll just assume every Hyundai at EA is just there for the free juice and they'll never invest in a home charger. The few times I ever used public charging and at different locations, it's plagued with tow trucks and charger issues.

Bring on NACS, I'll gladly pay the premium for the little public charging that I do. Without a home charger I would just keep my ICE vehicles at this point.

 

[voxel]

Because in miles/hour the least efficient cars are going to rate the slowest.

I also have an Ioniq 5 and it doesn’t receive much higher power in kW, the technology isn’t much different. The Hyundai is an 800V class vehicle but still only really charges faster because it has a smaller battery. Both vehicles can charge at >200kW.

I owned a Ioniq 5 Limited before the Rivian and it easily charged at 3C for 40% of the range (say 30-70%).

I rarely get over 1C with the Rivian. All the Teslas I’ve owned charged consistently at 1.5C or higher. Even my Mach-E rarely drops below 1C until 80% where it plummets to 0.5C.

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