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Comment by gambiting | Hacker News Reader

So you deliberately don't charge the battery to 100% then conclude the realistic range is shorter than advertised? I get you don't charge to 100% every day, but if you know you're going to drive further then....you do. Or just do what I do and charge to max each time, the battery is warrantied for 8 years, it's going to be fine.

>>Imagine your daily commute is 115 km (e.g. Roeselare-Brussel

That would be an extremely unusual commute to be doing by car in Europe, people do it but it's very rare. If you're going to be covering over 1000km a week(!!!!) Then get a good diesel, not a brand new EX90.

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Even if you do 100%, with just 1 year of used, my Tesla battery on 100% charge shows 320 miles, which is a far cry from 358 advertised.

Plus the other estimates are correct. The range drops if it’s too cold, or if it is too hot, or if you use any of the features that the car advertises, or if you’re driving on a freeway, or if it is a stop and go traffic, or if you gain elevation, or basically if you use your car as a car.

Don’t get me wrong, I still love my car and I would never drive an non EV again, and a non Tesla EV at the moment. But calling out the marketing bs is totally fair.

EVs do much better in stop and go traffic. I wouldn’t be surprised if some even exceeds EPA range estimates in those cases.

My experience has been that the car does best when you’re driving at a steady speed of 25mph without having to stop. This is based on the internal chart that Tesla provides.

When you’re in stop and go, you actually use a lot more energy to go from 0->X but do not regenerate back enough when you come down to 0. On the other hand, maintaining a steady 25mph uses a lot less energy as compared to 0->X. Again, this is based on the Tesla energy usage data that they themselves show in car.

I doubt it would outperform EPA estimates (you can only recapture energy not create it afresh with regenerative braking), but compared to ICE cars the percentage of stated range would be very high.

The Chevy Volt PHEV had an estimated 53-mile all electric range. During the summer, I routinely got 56-60, and once got 67.5 miles before the engine had to kick in.

It’s because air resistance is a much bigger drag on efficiency for an EV, so stop and go traffic is a bit more closer to its ideal efficiency (which is going slow without stopping).

USA traffic engineers love stop lights which force idling. Fortunately some European tech to stop/start the engine is arriving in USA. In isolated cases, some USA intersections are being converted to traffic circles. Installation of new stop lights should require a giant pollution fine paid by government.

My 2018 Ford escape has auto-stop/start when stopped. But it almost never works. No idea why. It worked for the first year maybe, then disappeared.

It can be turned off, and there's very little visual indication that this has happened. The feature bugs some drivers, so if you have a second driver, they could have easily done it.

I've toggled it many times to no avail.

Sometimes dealer updates change settings. I saw a Subaru change behavior with lane departure warnings after an oil change.

I've had this this issue on my Mercedes before, the cause turned out to be the 12V battery that never charged properly, so the system didn't want to activate.

I used a Nissan Leaf as my thrice weekly commuter vehicle for several months. It couldn't quite make the full round trip on a 100% charge and there was nowhere to plugin at work. For a while, I'd go to Ikea at lunch and charge there during my lunch break. That was enough extra charge to make it all the way home but going to Ikea each day for lunch got old fast. Instead, I started stopping at charge point near a Fry's on the way home but even Fry's got boring after a few days. Then I discovered if I got off the freeway about fifteen miles earlier than my usual exit and used surface streets, I could make it home even though it was a bit longer distance and plenty of stop lights, stop signs, and traffic slower than the highway. I suspect the lower wind resistance at the slower speed is what provided the extra bit so I could get home with about nine miles of range showing on the dash. Probably wasn't good for the battery but it was the last few months of a lease and never ended up losing any bars of range. The anxiety sure was real.

My Y is showing about 93% of rated range after 19k miles, FWIW.

> The range drops if [...] you gain elevation

That's true, but unless you're driving inexorably up into the Himalayas, you're going to come down that hill. EVs have a magic trick they can play in that situation. :)

In point of fact regenerative braking makes EV's equivalent range penalty in hilly terrain much (MUCH) better than any fuel-burning vehicle.

> What percentage should I charge the battery to? > > For regular use, we recommend keeping your car set within the 'Daily' range bracket, up to approximately 90%. Charging up to 100% is best saved for when you are preparing for a longer trip. You can adjust how full the battery charges from the charge settings menu. > [tesla.com/support/home-charging-installation/faq](https://www.tesla.com/support/home-charging-installation/faq)

> There are two reasons: charging performance and battery longevity. Most of the time you should only charge an EV to 80% because charging rates slow down dramatically past the 80% mark. And two, the long-term health of your vehicle’s battery pack is improved when kept below 100%. > [witricity.com](https://witricity.com/newsroom/blog/the-80-rule/)

The “charging slows down” is only true for DC fast charging. If you’re charging at home it doesn’t have an effect because the ratio of input energy to battery size is already so small.

That's only true of NMC batteries, not of LFP ones, which their Model 3 SR now ships with. With LFP batteries, it's better for them to charge them to 100%.

> That would be an extremely unusual commute to be doing by car in Europe, people do it but it's very rare. If you're going to be covering over 1000km a week(!!!!) Then get a good diesel, not a brand new EX90.

Aren't they in the middle of outlawing them?

More than a decade from now, and that’s assuming the EV market continues to advance the technology as much as is predicted.

There's no talk of outlawing any vehicles people already own. You won't be able to buy a brand new one in a decade, but there's no indication you won't be able to use one you already own.

Company cars in Belgium starting from this year have to be phev or ev. No more diesel or gasoline.

As in, new cars that companies buy from this year, right? If your company already owns a diesel vehicle it can be still used, correct?

Yes, from this year and applies to new vehicles allocated to employees. Companies generally lease or long term rent in Belgium. What I hear, people are now replacing their car parks.

Read the fine print, battery being under warranty often means they can replace your battery with a USED one with upto 30% range degradation.

That's a fantastic way to crater your cars resale value.

Why do Americans care so much about resale instead of just using the stuff you bought?

If I ever buy a house it'll be to actually live life in it, not to nickel-and-dime some poor college student.

It's double edged, the first edge is selfish, maximum extraction of value. The second is definitely not exclusive to Americans - taking care of your belongings and reducing the rate of sending things to landfill.

I agree this is a cultural problem. Houses are seen as retirement vehicle, etc. I think it's partially a sales tactic, to switch your brain into "investing" mode and willing to fork up a lot of cash and leverage (I'm "investing" in a Tesla, see how much gas i'll save?).

> Why do Americans care so much about resale instead of just using the stuff you bought?

I expect that you throw your old car away whenever you get a new one?

Many of us do, yes. Drive it until it’s primary worth is scrap.

But that doesn't make a very good mobile status symbol.

> Many of us do, yes.

I doubt it, because

> Drive it until it’s primary worth is scrap.

But that means selling it for scrap, which is still not "throwing it away".

Besides, a car that's 30 years old is still worth more than scrap, and even then, scrapped cars are still sold for money.

So, no, there are very few people either throwing or giving their cars away after driving it for however long it lasted.

Because the better the resale, the nicer the car you can afford to replace it. Most new cars are kept for 3 years and traded in, (or leased) so the better the resale the more money to put into your next car. Or if you lease the less your lease will be.

Those who buy used cars keep their cars longer, and are willing to pay more for a car they think will last longer.

Why not just get a much nicer and reliable car and keep it for 10-15 years?

The type of people who do that save money buy buying a 3 year old car. The people who buy new cars mostly wouldn't be seen in an older car.

How so, exactly? There's no way for anyone to check how much a battery was charged regularly, just like there's no way to check if a car was only used to drive to church once a week or driven like a hooligan hitting redline all the time - I'm not suggesting fraud of course, far from it - just that buyers have to assume the worst possible use case, and if so I don't see how actually regularly charging the battery to max affects the resale value at all. Besides, I don't expect the resale value to be very high after 8 years(realistically more) anyway.

I believe the SoC (state of charge) history is recorded for Teslas and other EVs. There is a company called Recurrent [1] which uses this data to estimate battery degradation. I think the idea is to generate something like a Carfax report for used EV battery packs.

[1] https://www.recurrentauto.com/

Yes, putting a lot of miles on any car is going to affect resale value.

This is not uncommon for people in Belgium to commute that far, especially in software.

Sure, there will be groups of people who are doing that. But to commute 200km a day? That will be something like 0.0001% of all workers, I cannot imagine it's any more than that.

You'd be surprised. Belgium is weird. Lots of companies in Brussels, which is central in Belgium. And lots of people commute in. Every day, going and coming back.

The freeways are clogged every morning going towards Brussels and every evening leaving Brussels.

I can believe the motorways are clogged, it's a capital city after all - but who lives 100km away from their workplace, and why? I knew someone who did this in Germany, but his argument has always been that actually, this is "only" 30-60 minutes away on the autobahn depending on conditions(which I still think was nuts), but from what you're saying people accept 2-3 hours per day(!!!!) In a car just to get to work? That's nuts, and again, I really doubt it's common in any way shape or form.

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