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Comment by dehrmann | Hacker News Reader

I always assumed EVs use regenerative braking as much as possible on their own.

They do. But if you brake too agressively, they switch to friction brakes. It pays off to avoid this: more mileage, marginally lower charging expense, lower cost on brake maintenance and fewer complaints from passengers.

"It pays off to avoid this: more mileage, marginally lower charging expense, lower cost on brake maintenance and fewer complaints from passengers."

Regen braking wears the hell out of your battery. That few hundred you saved on brake changes just cost you a tens of thousands of dollars on a premature battery replacement.

Source for your ridiculous claim?

I'm not sure why they think regenerative breaking is worse than any other charging modality.

It's an added charge cycle on the battery. A guy in San Diego does full EIS and more for EV cells. His data shows multiple shorter recharge cycles wear the battery down faster, no matter what range you try restricting the recharging to. Same data shows that the batteries are better when conditioned harder on their first charge, gaining much better cycle performance and count, at a minimal sacrifice of capacity.

And this exact same thing coincides DIRECTLY with my lithium-powered portable lighting, so I'm pretty up-to-date on very top-level research, because I hire this same person.

His name is Luke. You'll see him all over the globe doing lithium EV research and testing.

Most EVs will not use regenerative braking when the battery is over 80% which is where the damage mostly happens

Really curious about this, since regen braking is Standard on all EVs

A charge cycle is a charge cycle, regardless. The wear and tear that occurs during is cumulative and doesn't just magically disappear when restricted to a certain level of battery depletion.

Apparently you need to use the friction brakes now and then so they don’t degrade early, which could be a safety issue. I think as long as you’re using the car frequently it’s incredibly unlikely to be a problem though.

Not sure about all EVs and hybrids, but for Prius the friction brakes were used below a given speed as then regeneration becomes inefficient (as does stopping power). If you pay close attention, you might notice the transition.

Yup. I only use my car infrequently and it sits there with the handbrake on, when I do take it out often the rotors have rusted just slightly, meaning I get a "thunk thunk thunk" until I brake hard a couple times.

I think it's fine, in an EV just give your physical brakes a good test/try out when starting a journey in the car, especially if it has been sat for a while.

I imagine there to be a sweet spot with friction breaks where it grinds the hardest, I imagine it to be when one breaks gently.

No experience with EVs, but Toyota hybrids use regenerative braking a lot. They also teach me to accelerate gently. Quite the opposite of Tesla with their "ludicrous mode" encouraging extreme acceleration. But I have no idea how well those brake.

Most don’t. Not all have heatpumps either. In fact anything outside Tesla is still garbage.

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