The same logic applies to power delivery. If the pack has 200 cells, and is delivering 200 kW, that's 1 kW per cell, and that number is independent of whether the cells are arranged as 400 or 800V. BTW, the number of cells may be much greater than 200, but the same logic applies. - ThreadSky

About ThreadSky

jandjmh.bsky.social • 16 days ago

The same logic applies to power delivery. If the pack has 200 cells, and is delivering 200 kW, that's 1 kW per cell, and that number is independent of whether the cells are arranged as 400 or 800V.
BTW, the number of cells may be much greater than 200, but the same logic applies.

Comments

jandjmh.bsky.social•16 days ago

Motors: The difference between and 800 and 400 volt motor is simply more turns of thinner wires in the windings, or fewer turns of thicker wires. The power per volume or per kg is nearly independent of the operating voltage.

jandjmh.bsky.social•16 days ago

Wires in the car: a clear advantage for 800V. They can be thinner and lighter. That saves a few kg. Not insignificant. But not something that would have a notable effect on any performance aspect of the car.

jandjmh.bsky.social•16 days ago

Control circuits: 400V semiconductors are more common, less expensive, and can conduct higher currents with lower losses than 800V semiconductors.
Given that current at 800V are half as much, this is mostly a wash for the two possible choices.

jandjmh.bsky.social•16 days ago

If you got this far - thanks for reading. If you have thoughts on legit reasons why 800 volts is decidedly better, I'd love to hear them

animeshitposte.bsky.social•16 days ago

Because the limit is, in a real world practical sense, in the charging cable. An 800V fast charger can ramp to higher power levels much more cheaply than a 400V high current charger for all the same reasons the cars benefit from 800V. less metal or cooling/station = more stations (ceteris paribus)

animeshitposte.bsky.social•16 days ago

Obviously the voltage difference alone does not itself explain the reason why an e-GMP car like the ioniq can charge in 20 minutes rather than the 30 a model 3 takes, but there are very clear economic advantages to going with high voltages rather than high current.

Posting Rules

Be respectful to others
No spam or self-promotion
Stay on topic
Follow Bluesky's terms of service

Comments

Posting Rules

Reply