hqmp

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Higher voltage means lower amperage - or more energy for a lower amperage. Amperage creates heat, requires heavier wires, more cooling.

So being able to run at a higher voltage means generally lighter weight, faster recharging.

But... Safety? Not necessarily. If you were pumping the same energy, the same speed, you'd get less heat. But if you want faster charging, you're going to push that envelope.

And higher voltage needs more special insulation, newer more expensive electronics, etc. And it could result in the installed Supercharger network being incompatible.

-Crissa
Hi. Are you sure this is true? It's been a long time since I had physics, but I remember Voltage = I(amps) * R (resistance). If we use the same amps for a given process, I = V/R. Therefore, if you increase the voltage, you can increase resistance (smaller wires) without affecting the current. But voltage and amps are directly proportional, not indirectly. Again, it's been decades since I had physics, so please correct me where I am wrong.

 

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Isn't Tesla already shipping the V4 Superchargers?

It's likely that these new superchargers can charge at 800-900v.
 

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I tried diving into the twitter thread and couldn’t find anything that supports this claim, but I have heard Elon and Drew both say on several occasions that this doesn’t make sense and that Tesla won’t be doing it. If they have changed their minds I would need for ‘them’ to say so, and Whole Mars Catalog often spews BS.
 

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Yes he said does not make sense for existing production lines. CT and Semi are in the same buckets and new production lines. Even Roadster 2.0...
 


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I tried diving into the twitter thread and couldn’t find anything that supports this claim, but I have heard Elon and Drew both say on several occasions that this doesn’t make sense and that Tesla won’t be doing it. If they have changed their minds I would need for ‘them’ to say so, and Whole Mars Catalog often spews BS.
I believe Elon and Drew said 800V/900V did not make sense for Tesla existing models 3/Y.

Might be three reasons.
1. Engineering is already complete and models are in large scale mass production.
2. These models have only medium sized battery packs of capacity 50-90KwH.
3. These models at this point, 800V/900V charging would not give enough benefit vs risks and disruption to production.

Elon and Drew said 800V/900V might make sense for larger vehicles which have larger battery packs.
 
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I believe Elon and Drew said 800V/900V did not make sense for Tesla existing models 3/Y.

Might be three reasons.
1. Engineering is already complete and models are in large scale mass production.
2. These models have only medium sized battery packs of capacity 50-90KwH.
3. These models at this point, 800V/900V charging would not give enough benefit vs risks and disruption to production.

Elon and Drew said 800V/900V might make sense for larger vehicles which have larger battery packs.
Thank you for the reminder. I don't suppose that you have seen a post from them saying that the CT will use this 800/900 V architecture. I would still want to hear it from Tesla rather than Whole Mars Catalog or at least have a traceable source.
 

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Thank you for the reminder. I don't suppose that you have seen a post from them saying that the CT will use this 800/900 V architecture. I would still want to hear it from Tesla rather than Whole Mars Catalog or at least have a traceable source.

I agree with you, that as far as I know, nobody at Tesla has confirmed Cybertruck would be 800-900V.
 

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If the towing data from F150 lightning and R1T have confirmed anything, it's that we'll be at charge stations often and for long periods. Large 200kwh batteries are too cost prohibitive so faster charging seems to be the answer right now. Higher voltage seems like a good idea for trucks for this reason alone.
 

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What does this mean? 800 vs 900?
It means 12.5% more volts.

Considering Musk has said the benefits of 800v versus 400v were fairly small, I have serious doubts the difference between 800 and 900 would be very big/ interesting.

This is mostly just confirming Cybertruck Will have higher voltage.
 


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Can someone please explain what this means? Does it mean better charging times? More utility, better safety?
In addition to Crissa's response, I am curious if the 900V system is the nominal rating, or hot off the charger. If its HOC, we probably dealing with a battery pack that has 215 cells in series and paralleled X amount of times to get the desire 120-200KWH storage capacity. I never owned a tesla, so I am guessing that this vehicle's battery packs cell series are divided into segment/banks for charging purposes. This would allow a lower volt charge, and huge amps being pushed to quick charge. Again, I am not 100% this is the case and I hope someone chimes in and corrects me. I just find it very unlikely that home, destination, or quick charger are actually inverting volts and pushing 800 or 900 volts to charge the battery of these machines.
 

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Hi. Are you sure this is true? It's been a long time since I had physics, but I remember Voltage = I(amps) * R (resistance). If we use the same amps for a given process, I = V/R. Therefore, if you increase the voltage, you can increase resistance (smaller wires) without affecting the current. But voltage and amps are directly proportional, not indirectly. Again, it's been decades since I had physics, so please correct me where I am wrong.
@Crissa is always right f.y.i. rewording what she said. Power measured in watts equals current measured in amps x voltage.
P=i(e). It's not that you are incorrect E =I(r) it's that it's the wrong formula for the answer to the question.
A 900v architecture would allow the same power at a lower current which means you could use thinner conductor. This is offset by the thicker insulation.... Somewhat. Less conductor is lighter and cheaper.... But that is really the only benefit. It doesn't increase the amount of power the pack can hold, it doesn't increase safety in fact it's probably less safe.
 

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Hi. Are you sure this is true? It's been a long time since I had physics, but I remember Voltage = I(amps) * R (resistance). If we use the same amps for a given process, I = V/R. Therefore, if you increase the voltage, you can increase resistance (smaller wires) without affecting the current. But voltage and amps are directly proportional, not indirectly. Again, it's been decades since I had physics, so please correct me where I am wrong.
Yes, I'm sure, because that's what I said? You're just looking at the wrong direction of the formula. That's for calculating a load imposed by a piece of wire or machine. When you force current through a resistor, the voltage 'drops' across the system, and that's your formula.

But raising voltage lowers the amount of amperage required for the same energy (wattage). That's us messing with your carefully balanced formula.

-Crissa
 

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I tried diving into the twitter thread and couldn’t find anything that supports this claim, but I have heard Elon and Drew both say on several occasions that this doesn’t make sense and that Tesla won’t be doing it. If they have changed their minds I would need for ‘them’ to say so, and Whole Mars Catalog often spews BS.
Nah, they're always honest.

 

 
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