R1T / R1S EPA Test Documentation Confirms Some Details: 210 kW peak DC charging, no heat pump

[fotoflux]

It's possible just some trickery of dual 400v parallel charging via reconfiguration of battery packs using the busbars. It is in fact what rivian has a patent for. We just don't know if it's real or not.

Do you know where the patent for this is published? It sounds like the difference between wiring 2 1.5v batteries in parallel to double the amperage vs in series to double the voltage to 3v. Obviously this battery pack has hundreds of tiny batteries so I am wondering if there is some trickery in the HW that can change the power flow dynamically

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[AndroidAppBundle]

This has been part of my fear with my R1S and Rivian in general. It is taking so long for them to bring something to market, that by the time they do; brands like Hyundai and VW will have competing or better technology.

I think what were learning is that Rivian is no Lucid, or Tesla. Rivian will make EV's, but they won't exactly be pushing the envelope on EV tech (cold weather range performance, charging curve & 0-80% performance, etc).

Then I worry that the battery packs on the Rivian are so large, that the costs can't stay this low for long (significant price hikes have to be coming).

I wish Rivian could just deliver vehicles to real people not bound by NDA, so we could learn

This is the biggest factor and limitation with a 400V-450V architecture.

Electrify America, the largest 350kW charging network in the US is limited to 500amps. With a 400V battery, the max charging rate is 200kW. This is why companies like Porsche and Lucid are using 800/900V packs which allow for a higher charging speed (270kW+) while drawing less than 500amps (the limit of the charger).

So even if the R1T/R1S can handle a higher charging speed, the chargers themselves might be the limiting factor. Which is a bummer. A 200kW limit with a 135kWh+ pack is relatively slow compared to some of the other modern EVs. That's 0-50% in 20 minutes under perfect condition with no charging losses, and maintaining 200kW for the entire 20 minutes. Again that's not bad, but we have cars like the Taycan, Ioniq 5, and Lucid going from 0-80% in about the same amount of time.

 

[astonius]

Because they’re California/Texas centric? Heat pumps are technically more efficient in most mild climate, but really don’t work efficiently below 25-30 degrees.

That doesn’t make any sense. Tesla is by far the largest EV maker in the world right now, not just California and Texas. They even added the heat pump to their volume cars first.

 

[Drterreur]

That doesn’t make any sense. Tesla is by far the largest EV maker in the world right now, not just California and Texas. They even added the heat pump to their volume cars first.

They did after a while. My model 3 has resistive heating.

My nissan leaf also has a heat pump. However, it doesn't to any good outside of fall and spring. Also, depending on the setting, you even have to choose between heating air with your heat pump and drying it with air conditionning such as in the defog setting(can't do both at same time).

 

[R1S Maineiac]

Appreciate the primer, but counterpoint: if they are only efficient in a narrow window why did Tesla put forth the effort to add them to their vehicles?

As a former a Tesla owner, I constantly grumbled "designed in California" every time one of my cars suffered a design flaw. (Icy door handles, falcon wing doors in snow, etc)

TL;DR Tesla designs cars for California and not the extremes. Just because they put it in their cars doesn't mean it works wonderfully everywhere.

 

[astonius]

As a former a Tesla owner, I constantly grumbled "designed in California" every time one of my cars suffered a design flaw. (Icy door handles, falcon wing doors in snow, etc)

TL;DR Tesla designs cars for California and not the extremes. Just because they put it in their cars doesn't mean it works wonderfully everywhere.

Tesla’s entire ethos is to remove as many parts from the car as possible. This doesn’t explain why they would spend the time, effort, and money to add a heat pump if it didn’t work well outside of California.

 

[R1S Maineiac]

Tesla’s entire ethos is to remove as many parts from the car as possible. This doesn’t explain why they would spend the time, effort, and money to add a heat pump if it didn’t work well outside of California.

They also do production simplicity.

If they decide they're gonna put it in the car, they don't really make it a selectable option. Everyone gets it.

 

[astonius]

They also do production simplicity.

If they decide they're gonna put it in the car, they don't really make it a selectable option. Everyone gets it.

Exactly. So if the options are a) design a brand new heat pump that only works in limited climates and adds complexity and cost for every car, or b) rely on resistive heat only, there’s no way they’re picking option A unless there’s something we don’t know or Tesla’s heat pump has some secret sauce.

 

[Sdvictor]

That doesn’t make any sense. Tesla is by far the largest EV maker in the world right now, not just California and Texas. They even added the heat pump to their volume cars first.

It absolutely does. I work for a FAANG company. One of the most valuable companies in the world. Everything we do is so myopically Bay Area centric, it’s hilarious

 

[astonius]

It absolutely does. I work for a FAANG company. One of the most valuable companies in the world. Everything we do is so myopically Bay Area centric, it’s hilarious

I work for FAANG too. We don’t design complexity into products if it isn’t adding broad value.

 

[R1S Maineiac]

Exactly. So if the options are a) design a brand new heat pump that only works in limited climates and adds complexity and cost for every car, or b) rely on resistive heat only, there’s no way they’re picking option A unless there’s something we don’t know or Tesla’s heat pump has some secret sauce.

And my point was they don't necessarily always get those decisions right.

 

[ajdelange]

Because they’re California/Texas centric? Heat pumps are technically more efficient in most mild climate, but really don’t work efficiently below 25-30 degrees.

Yes, but they do work. While a COP of 4 may be attainable at 45 °F COPs of 2 or so can be realized down to below freezing. Remember that the theoretical COP for a 20 °C cabin with a - 10 °C ambient is 9.76. True, for a +10 °C ambient the theoretical COP is 29.3.

 

[atlastracer]

I wish Rivian could just deliver vehicles to real people not bound by NDA, so we could learn

As of this weekend (at least, though I'm sure before this weekend but new owners didn't post about it) they are. A user on Reddit had their r1t delivered. No NDA (someone asked).

So we'll start to see those info coming out s00n.

 

[Trekkie]

That doesn’t make any sense. Tesla is by far the largest EV maker in the world right now, not just California and Texas. They even added the heat pump to their volume cars first.

Don't think it'd sell in the Nordics as well as it does if it was designed to work in TX and CA.

You can say a lot of bad things about Tesla and it's CEO that are accurate but to think they only test their vehicles in those two states or design for those two is laughable, especially since they've not made anything in TX and everything we're seeing today is easily a year old design done in CA.

Their cars would be failing everywhere if that were the case.

 

[SeaGeo]

185 isn't BAD on a 135kWh pack..... And neither is 210.

I certainly hope they crank up the juice for the Max pack, though.

Agreed. Also, not great. With a pack as large as the large pack (and obviously the max pack) there's very real benefits to higher voltages allowing 300+ kW charging without having to use a super aggressive charging curve.

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