this post was submitted on 24 Nov 2025
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Electric Vehicles

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Electric Vehicles are a key part of our tomorrow and how we get there. If we can get all the fossil fuel vehicles off our roads, out of our seas and out of our skies, we'll have a much better environment. This community is where we discuss the various different vehicles and news stories regarding electric transportation.


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One of an 800-volt system's greatest benefits is that it requires half the amperage of a 400-volt system to return the same charging speed, as multiplying voltage by amperage provides the charging speed. Higher charging rates incur more losses, so by lowering the current and raising the voltage, the whole process becomes more energy efficient.

Another win for the 800-volt system is that, due to the lower amperage current within the EV, thinner cables can be used.

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[–] zockerr@lemmy.world 19 points 1 month ago (2 children)

But that doesn't matter in case of EVs, since 800/400V refers to the battery voltage. The motors are driven by variable voltage and frequency AC that is completely decoupled from the battery voltage.

[–] acockworkorange@mander.xyz 4 points 1 month ago

I wouldn't say it doesn't matter. If your motors are rated for the full voltage (and why wouldn't they be?), they will have higher maximum torque. Or you can use smaller, lighter motors.

I haven't worked with EVs, so l but I did quite a bit with stationary, industrial, synchronous motors driven by VFDs. In that application, the V/f curve is used mostly to control torque and power efficiency. But the voltage drop isn't that dramatic.

I imagine the EV brain would do clever things such as increase voltage to accelerate the car, while reducing it in cruise to reduce power draw. But there are clear advantages to having a higher voltage battery.