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Comment by lotsofpulp | Hacker News Reader

I thought braking aggressively increases range.

What? How did you arrive at that conclusion. Even if the laws of thermodynamics and entropy took a holiday, and you recovered 100% of the energy when you brake, at best you would break even and not hurt your range (vs not braking aggressively).

Regen breaking increases range over no regen braking, but braking aggressively will always be worse than not braking aggressively.

No? Accelerating and decelerating are both lossy, and for the brief intervals when you're going faster you're also taking additional wind friction loss.

Most EVs (including Tesla) do have regenerative braking, so some of your energy is converted back into electricity when you brake, but nowhere close to all of it, so people who have a smoother, less aggressive profile will get more range.

Also if you brake really aggressively, you're dissipating more energy than can be successfully harvested and the rest is converted to heat, losing the energy you paid for and also increasing maintenance costs.

I see, thanks for explaining!

Yep. That's why I just leave a brick on the brake pedal. Infinite range!

if you brake too aggressively then you will use brake pads as well as regen, and that wastes energy.

Also, its still better to arrange to not need to brake at all, than to regen, since regen is not 100% efficient.

Braking doesn't increase range. Rather the natural foot off pedal regen braking increases range. If you physically slam on brakes, I'm sure that doesn't help range.

That's a Tesla problem. They couldn't figure out blended braking. If I press the brake hard in my car, the regen goes to max possible.

That is an accurate meter, it is not a Tesla problem. My PHEV works the same way, but that fact isn’t really relevant.

The meter is presenting you the regeneration “rate” but what you’re thinking of is the regen rate integrated over time, I.e the amount of charge recovered during the process of stopping, which the meter is not showing you.

Maybe, I don't really care about regenerative rate, I just notice my meter going to max when braking hard. I only use the battery for city driving and hard acceleration on the motorway anyway. It's great for merging onto the Spanish motorways.

But the comment showed you do care, you brought it up and pay attention to it. It’s all that the meter shows that you mentioned.

I'm sure that if you "slam on the brakes" (per GP), your car will take region to the max and the apply the real friction brakes, causing lots of kinetic energy to be converted to heat and "wasting" energy...

(Also, Tesla cars do have blended braking between region & friction...)

You can also recharge the battery by going in reverse, a solution I'm baffled more people don't know about.

Not if you use the break pedal

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