Porsche Taycan

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P.S.
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Re: Porsche Taycan

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Cold Fussion wrote:
22 Sep 2019, 06:25
Why is cooling an EV so difficult given how efficient the drivetrain is? Do the batteries require some very narrow temperature range that also happens to be very low?
In a Model S the battery is not the bottleneck when fast driving, its the motor. And as we can see, with the "Plait" they have something in their pipeline.

Basically an electric Motor is very compact in its size, so its hard to remove the heat, even it is indeed very efficient.
To give an extreme example: There are actuall electric Motors available where you can pull 20 kw/kg out of it, operating in its peak efficient area. But then even with 97% efficiency you need to remove 600 W heat per kg motor. Same for regenerating.

Lithium batteries are ion conductors. So basically every plus 10 degrees (Kelvin) the internal resistance halves. Until it catches fire. That is why you have to tell your Tesla you wanna execute ludicrous mode. It then will heat up the battery so it can provide the power without damaging.

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hollus
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Re: Porsche Taycan

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You probably mean "cool" in that last sentence?
Rivals, not enemies.

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P.S.
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Location: Germany

Re: Porsche Taycan

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No. But sure it seems odd. If the battery is to cold and the internal resistance is high, the ludicrous mode is a bit like a short circuit for the batterie.
In that case the current flow is not homogen inside the batterie, - little hotspods (molecular size) appear where the current is going even quicker, - until it becomes that hot, tiny little areas inside the batteries get distroyed.

I got told this context without being into the industry myself, so I would appreciate if someone can confirm my words.

Tommy Cookers
Tommy Cookers
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Re: Porsche Taycan

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P.S. wrote:
22 Sep 2019, 12:06
In a Model S the battery is not the bottleneck when fast driving, its the motor.
.... There are actuall electric Motors available where you can pull 20 kw/kg out of it, operating in its peak efficient area. But then even with 97% efficiency you need to remove 600 W heat per kg motor. Same for regenerating.
how is 600 W/kg a problem with liquid cooling ?
though the drive aka controller is also less than 100% efficient

btw
someone wrote that the Taycan has 2 gears
how does this compare with the Tesla that people are comparing with it ?

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P.S.
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Joined: 23 Oct 2011, 17:09
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Re: Porsche Taycan

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Its not a problem, it can be solved as the Taycan shows ;)

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P.S.
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Re: Porsche Taycan

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Tommy Cookers wrote:
22 Sep 2019, 13:01
... Taycan has 2 gears
how does this compare with the Tesla that people are comparing with it ?
Maybe this answer your question?
https://www.youtube.com/watch?v=wDEj1dbKKlU

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RZS10
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Joined: 07 Dec 2013, 01:23

Re: Porsche Taycan

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