Rivian R2 and R3 probably won’t be 800V

• Rivian CEO R.J. Scaringe told reporters that the 800-volt architecture is “not as critical” for small to mid-sized products like the R2 and R3.
• While other companies use higher voltage architectures to provide better charging times, Scaringe says incredible charging speeds are possible with 400-volt systems.
• Given that the R2 is supposed to be cheaper and, ideally, more profitable for Rivian, it likely won’t use an 800-volt system.

Rivian has not yet announced whether the upcoming R2 and R3 midsize cars will use a 400-volt architecture or a more expensive 800- or 900-volt system. Fans can hope that the next generation of products will move to a higher voltage architecture, which typically offers faster charging and greater efficiency. But after meeting with Rivian CEO RJ Scaringe, I don’t think that’s likely.

During a roundtable with reporters, Scaringe said that while there are benefits to moving to 800V, they are more important for larger batteries. Larger packages such as R1 are more likely to be voltage limited. But with the smaller battery pack we expect to see in the R2 and R3, Scaringe says battery chemistry is a bigger limiter than voltage.

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In R2, this step is “just not as important,” he said. “With R2, we optimized the cost more to ensure great performance, but (at) these price points. I don’t think it’s that important for a smaller car.

He didn’t directly confirm that the products would have a 400-volt architecture, but he sounded pretty confident that an 800-volt system wasn’t needed for the R2 or R3. The larger R1 “will need to transition” to an 800-volt or 900-volt setup, he said, but didn’t say when. Such a significant change is unlikely until the next redesign of the car.

Hyundai, Kia, Lucid and Porsche are bullish on 800- or 900-volt architectures. Their cars show why this technology is attractive: the relatively affordable Hyundai Ioniq 6 can accelerate from 10% to 80% in just 18 minutes. The Porsche Taycan can do this in 16 years. It’s incredibly fast. But Scaringe says the focus on tension is misplaced. Although an 800V battery can provide charging rates of 350kW or higher, in most smaller or mid-size cars, voltage is not the limiting factor.

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“We believe that ultimately the charging time should be less than 20 minutes for this 10-80 time. We 100% agree with this. You can achieve that with (400V),” he said. A 450V, 500A charger can provide 225kW of power. If a car with a battery capacity of less than 100 kWh could maintain these speeds, it would be capable of accelerating from 10 to 80% in 20 minutes. For proof, look no further than Hyundai. Despite its 800-volt architecture, the Hyundai Ioniq 5 or Ioniq 6 will “only” peak power around 220-230 kW. Some 400-volt vehicles, such as the Tesla Model 3 and Rivian R1, can achieve similar performance. Hyundai simply holds higher speeds longer, delivering super-fast charging times.

But this shows that tension is not really the problem. Many existing battery packs simply cannot accept that amount of power long enough to provide that kind of runtime. An 800-volt system would probably help, but cell chemistry and battery cooling are more important, Scaringe says. He didn’t mention it, but the implication is that the cylindrical “4695” batteries the company plans to use in the R2 and R3 should have better thermal performance than existing batteries.

Let’s see if they are good enough to achieve the target charging time of less than 20 minutes. For now, Rivian only claims that the R2 and R3 will be able to charge between 10% and 80% “in less than 30 minutes.” Achieving results in less than 20 years is a much more difficult task. Given that Scaringe called this a long-term goal rather than a promise, there is no word on whether R2 or R3 will achieve it. However, if they do, it probably won’t be with 800-volt architecture.

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