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Comment by olliej | Hacker News Reader

So it sounds like the range increase is for new cars? (Other comments made it sound like a software update to existing cars)

I still wish there was more focus on range over acceleration, obviously electric motors don't suffer from general efficiency impact as ICEs do (an ICE with superior acceleration seems to take an efficiency hit at all speeds), but how much of that "faster acceleration" impacts efficiency over the course of driving a few hundred miles.

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Range and acceleration mostly go hand in hand. Much of the constraint on acceleration is how much power you can pull from the battery pack, and that gets better with larger batteries. It’s not like a normal car where high acceleration means a big, inefficient engine.

Agreed, that was why I noted the efficiency model for an electric engine is superior to ICE. I'd just rather "normal"-ish acceleration in traffic with range improvements over high max acceleration. I'm sure you could also reduce engine weight if you don't have to rely on extreme acceleration.

You don’t have to floor the pedal. The tradeoff is decided by the driver. Accelerate less aggressively, get better range.

The motor is pretty small. The benefit from making it weaker would be tiny, if any.

basically none. I've read that many electric motors are most efficient at 80%+ load...

The problem is more that you hurt efficiency when accelerating fast. I'd rather a moderately reliable increase in range than improved periodic acceleration.

Essentially this is: How much does (say) 25-55mph in 2s vs. 4s cost for overall distance in normal traffic.

That said I have better things to spend 60k on than a car. (my last car was $18k, and 42k can be used for a lot of good things that aren't a fancy car. That said I would rather a car that can accelerate faster than a Prius C - my old 9k Yaris did much better, even though it used more gas)

You modulate your rate of acceleration with your right foot. If you want a car that accelerates from 25-55 over 4 seconds, drive that way...

The rate of acceleration is mostly irrelevant for the fuel consumption, unless your engine gets in a less efficient operating mode, which is not the case with electric motors. Often enough, this is not even the case with combustion engines, especially natually aspirated ones. Only if the higher acceleration also leads to overall higher speeds or additional breaking, energy is wasted. Otherwise, the energy used for accelaration is the difference of the kinetic energy at the high minus the one at the low speed.

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