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by wpm 342 days ago
Sadly, the lack of good sense and typical selfishness and shortsightedness of a human being means that when you don't, you get the spate of e-bike battery house/apartment/highrise fires that were hitting NYC. You kinda can't fuck around with li-ion.

I don't like that my Bosch e-bike batteries have closed-source schematics, software, and chargers (i mean really, what the fuck am I going to steal Bosch), nor that the software that runs on the bike is utterly locked down to the point where I can't even pay for a copy (it's available only to e-bike dealers and none of them have leaked it as far as I can tell), but unfortunately, I have no trust in my fellow schmuck to not accidentally or negligently build bombs when they rebuild their battery packs, nor would I trust them not to do stupid shit with the e-bike software like remove speed limiters.

I barely even trust myself to rebuild packs, and I kinda-sorta know what I'm doing, which is just enough to get myself into trouble. I still look at the two packs I have rebuilt with a side-eye, months and years on from when I built them.

3 comments

This kind of comment is ridiculous in light of the last hundred years of transportation which worked on gasoline, a highly flammable liquid fuel that can even explode under some circumstances. Why do we trust people to handle gasoline safely, but Li-ion batteries are a bridge too far?

I'm tired of being treated like an idiot consumer because someone, somewhere, fucked up their Li-ion battery.

We don’t let people fill up their cars inside their residences either. Lithium ion batteries are additionally dangerous because the fires burn hotter, are self oxidizing, and can’t be extinguished with conventional fire extinguishers.
Good point that people generally don’t fill up their cars in their home. Though I know people have really hurt them selves trying to use gasoline to ignite a bonfire and such. Gasoline fumes are extremely dangerous

Battery fires are not hotter. An EV battery fire and ICE car fire actually have fairly similar heat energy profile. ICE cars are a bit more intense. There’s a study from Sweden that set fire to similar ICE and EV cars and measures the energy. A gasoline tank will typically store a lot more raw energy than an EV battery.

They are self oxidising if the electrolyte burns away. That’s true. The anode and cathode is shorted and you get thermal runaways. That’s why it’s a bit of a challenge to fully put out a battery fire. Next gen solid electrolyte batteries fixes that to some degree.

Of course you can extinguish a battery fire with a fire extinguisher, or just water. The problem is that thermal runaway will make the battery really hot again, which will reignite anything flammable around the battery. So you need to keep it cool for a long while, generally by spraying or submerging it in water.

> Of course you can extinguish a battery fire with a fire extinguisher, or just water. The problem is that thermal runaway will make the battery really hot again, which will reignite anything flammable around the battery. So you need to keep it cool for a long while, generally by spraying or submerging it in water.

We actually had an issue with this at Robocup one year, where one of the teams charged their battery at 3C and then blew it up. We didn't have a Class D extinguisher within reach, so we blasted it with a CO2 extinguisher while someone ran to get a class D extinguisher. The battery kept burning after blasting it with the CO2 extinguisher, but at a much reduced pace, and the perpetrating team took a selfie with their burning battery.

Yeah, lithium ion is pretty dangerous and not to be fucked with… but actually we do allow filling up cars in private residences… You can just go get a fuel can or extra tank of your choice, fill it up at a station when fuel is cheap and keep it at home for a cheap top up to avoid having to go out of your way for cheap gas on those days when your low but not going near a gas station with good prices… no laws against it at all here in Australia and we’re a crazy nanny state so I’d be surprised if it was illegal somewhere else… except maybe California, where the fuel can is probably illegal to own if you don’t put a warning sticker about possibly causing cancer on it or something ridiculous like that.
This is a ridiculous point of view. Those things are not mutually exclusive; you do not need to have complete proprietary lockdown to have a properly built quality battery.

Humans will lie and cheat for profit but at the same time humans also build locked batteries. It's just that nowadays we take away responsibility of people and their choices and we don't want to deal with the fact that when someone is buying a shitty poorly built copy, they are the ones at fault because of their greed.

You could very much have an open market (and should) it's just that people would rather believe there is nothing wrong when they buy something that is suspiciously cheaper than it should be.

Greedy corporations are at the origin of the problem precisely because they try to extract too much for their stuff, selling it at what is an unreasonable price.

You cannot at the same time blame people for their poor choices out of greed and at the same time re-enforce the same behavior in corporations, that's nuts.

> nor would I trust them not to do stupid shit with the e-bike software like remove speed limiters.

I’m not going to lie, this is the first thing I would do if I could flash e-bike software.