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It’s physics, there’s no way around it. You expend a ton of energy——battery heats up. Without massive radiators there’s nowhere for that heat to go.


No, it's incorrect, physics does not mandate that battery should heat up as you expend energy. Ideally all the energy would go into kinetic energy and be dissipated by friction losses due to air or contact between the road and the tires. The battery heats up only because the process of tranferring the chemical energy from the batteries to the car motion is imperfect, and there are internal losses do to the internal resistance of the battery.

I'm not saying that Tesla has invented a sufficiently efficient battery, but to vaguely claim "physics" makes it impossible is wrong.


It does. It will heat up. To quote a physics textbook: “Power transfer between a voltage source and an external load is at its most efficient when the resistance of the load matches the internal resistance of the voltage source.” IOW in the configuration where the power transfer is at its most efficient, battery has to dissipate as much thermal energy as motor(s) are consuming. Too much internal resistance and most of the thermal energy ends up in the battery. Too little, and your motors aren’t going to do their best. But in either case even with the load that’s not 100% matched, you do end up with a ton of heat dissipation in the battery when a heavy car like this is driven hard.


That sentence from the textbook is poorly worded, see https://en.wikipedia.org/wiki/Maximum_power_transfer_theorem...

Yes, power is lower when efficiency is greater all other things equal, but you work around that by not making all other things equal.


You get voted down by people who just want to believe stuff, physics be damned. Doesn't matter that the same exact thing happens to the existing S models which manage a more than decent 0-to-60 performance on paper (they're in the same league with the Lambos and the Ferraris), but because of those damned physics I don't think that any of them actually completed a Nurburgring lap (that's ~7 km driving the S model like a sports car).


Perhaps getting down downvoted by people who expect Tesla may have thought about this. I remember reading the overheating was due to the regenerative braking trying to push power back into the battery so it was getting hard charged and discharged constantly and you couldn't switch off the charging. The bigger battery may be so you can switch off the regenerative braking.


Really? Are you saying 7 mins of hard driving will render it literally unable to continue?


The S will go into reduced power mode after 7 minutes of track grade driving: https://jalopnik.com/heres-what-a-tesla-model-s-can-do-aroun...

It’s not a track car...what do people expect?


https://insideevs.com/expected-tesla-model-s-fails-lap-nurbu.... Not “unable to continue” perhaps, but unable to deliver a sports car-like performance.




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