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Comment by solardev | Hacker News Reader

> It can also be tricky to open the door on the Model S with a drained battery. Under normal circumstances, the car automatically adjusts the windows to ease the process. "Always connect to an external, low voltage power supply before opening a door when the vehicle has no power," Tesla says, "to avoid breaking a window."

It's such a silly situation to be in. Why couldn't they have made these with regular door handles?

Edit: Oops, sorry, it's not the handles but the window design. Still, seems needlessly complicated and fragile.

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It's not the door handles that is the issue in that quote. It's the frameless windows. Cars with frameless windows often need to retract the window slightly when the door is opened, so that the window clears the edge of the body of the vehicle that they tuck up into when it is closed. Many other vehicles do this as well.

Frameless windows is an example of over complicating vehicles with needless technology that inevitably breaks and really doesn’t add anything to the experience of the vehicle. I am unclear why manufacturers keep designing features like this.

It is worth noting that not all vehicles with frameless windows require the glass to be retracted to clear the frame. It is mostly a cosmetic thing, but also, it is practically impossible to offer a convertible version of a car without it.

This seemed entirely separate to the rest of the article. No one is literally running their battery down to absolutely nothing - they are just having longer queues than average at the charger. And if you do run your battery down to exactly nothing, this can be an issue even on a hot day.

The model 3 will open the window a bit when you open the doors, but if you use the mechanical override, it doesn't break the window, it just risks damage to the rubber seal around the window. I believe it's not really a problem unless you use that as your normal method to open the door for an extended period.

My e46 BMW had frameless windows and it was built in 1999. I prefer frameless windows after having that car. My newer cars don’t, the windows are harder to clean and don’t look as good.

I think I'll take "windows that don't break when it's cold" over "windows that look better when cleaned" any day. But that's just me... ever the utilitarian, I guess, lol. Different cars for different folks!

Side rant: Mainly my gripe is that there still aren't affordable electric utility vehicles. Tesla's way too much of an "image" and fashion car for me, and I wish there was some bog-standard AWD SUV that's electric or a plug-in hybrid. The Subaru Solterra (a rebadged Toyota with AWD) is close, but very expensive.

The Chevrolet Equinox EV might be what you're after, although it's not available yet (was supposed to be available Q1 this year, it's slipped): https://www.chevrolet.com/electric/equinox-ev

No one is breaking frameless windows unless they yank the door extremely hard when the battery is dead or I guess if you let it freeze over and don’t chip ice away. Never heard of it ever happening on the BMW forums. Only some random Canadians fried of a fried.

Not the handle it's the frameless window, which is my least favorite feature on my car. It's just needlessly complicated and throws passengers off all the time.

Why don't they reserve some power just for that or have a separate battery using different technology? It's not a rocket science to have a low capacity battery which can last years in freezing temperatures.

FWIW, the low voltage system is separate from the high voltage system in most vehicles with electric drivetrains.

Do you know how do these teslas become dead? I mean after you cut off wireless communication, wouldn't they be able to stand in freezing temperatures for years even with lithium based batteries? I know capacity will be reduced, internal resistance higher etc but still I don't get how do they discharge enough not to even be able to open the door.

Low voltage circuits have constant draws attached to them. Simple circuits like keeping clocks ticking, and more complex circuits that listen for wireless keys or alarm sensors. Ideally, they can last for months with those draws, but when the battery is old and cold, it can die in weeks or even days.

FWIW, the high voltage circuits (the one with the Li batteries) are physically disconnected with a contactor (a high voltage relay) once the car is turned off. You can literally hear the clicks inside the car as you turn it on and off.

All that said, I have heard of some cars which can charge the low voltage battery using the high voltage circuit, but I know nothing of those those are connected.

Are you aware of any that don't have a low voltage battery?

Nope.

Low voltage batteries are generally a bit more susceptible to the cold, since they don't have heaters and have a lot of constant draw circuits attached to them.

Pretty much every car with frameless windows works the same way. The window rolls down a little bit when you open the door to clear the trim.

Mini, Audi, Mercedes, Corvette, and so on. They all work the same.

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