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When I Took My Zipcar Into the Wilderness

theatlantic.com

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Re: When I Took My Zipcar Into the Wilderness

#71

Post by pdkl95 »

williamstein wrote: post #32
ebg13 wrote: post #11

Earlier quoted context omitted.

> If the battery is flat on the car then you are still pretty much out of luck even if you can get in. With an EV yes, but not with an ICE. Just keep a jump box in your trunk.

These "jump boxes" are amazing! I used to keep big jumper cables and have AAA in case of a dead battery. Last time AAA came (after I waited hours...), they just pulled out a little "jump box" and instantly started my car. I found and bought a random one on Amazon (there are dozens -- https://www.amazon.com/s?k=car+jumpstart ). It's very small, can also be used to charge a cell phone, as a flashlight, etc., and really…

Note that the battery in a "jump box" is probably capable of discharging a dangerous amounts of energy at very high current. BigClive measured[1] over >500A when he tried to discharge one of these batteries, which didn't actually work. The internal Li plates probably separated, breaking the circuit before fully discharging. After starting to disassemble the battery and realizing the that the plates had separated he attached a voltmeter and measured a full 3.6V across the supposedly-discharged, partially disassembled battery (squeezing the battery with his hands, "This still is fully charged, but it's just puffed up... that's a bit scary." Later, after the Li plates start changing color (!) - probably metallic Li starting to rapidly oxidize - they spontaneously ignited (pyrophoric).

The benefits of having a spare "jump box" in the trunk are obvious, but it's important to remember that this means carrying a dangerous amount of energy in form that is a very serious fire risk if anything damaged the battery.

[1] https://www.youtube.com/watch?v=0tGK1nqXr28

Re: When I Took My Zipcar Into the Wilderness

#72

Post by oh_sigh »

isostatic wrote: post #50
rebuilder wrote: post #42

Earlier quoted context omitted.

I haven't used any of the services you mention, but an on-line rental service I have used has a simple system: they unlock the car remotely when you start your rental, and the key is in the glove compartment. You may run into issues starting your rental, but lack of connectivity won't stand you in the middle of nowhere. Is there a particular reason these services can't just leave the keys in the car? Theft?

If the car has no signal, how is it unlocked?

They could give your phone a signed token indicating your rental times, and then let your phone directly connect to the car to hand it off.

Presumably it is easier for a human with a phone to move to a location with service than moving a locked car, usually just out of the cave you're in.

Re: When I Took My Zipcar Into the Wilderness

#73

Post by drfuchs »

mirimir wrote: post #25
wolrah wrote: post #20

Earlier quoted context omitted.

> That depends on the vehicle. If it's an ICE with a manual transmission, and you can get it moving fast enough, you can pop the clutch to start it. This depends on just how dead it is on newer cars. If it's able to run the electronics but just unable to crank enough to start, this can work. If it's dead enough that you can't unlock the doors it's probably also dead enough that the fuel pump, ECU, etc. aren't going t…

Good point. I should have noted that I've only done that with a 60s VW Bug. Just to see, I have turned off and restarted my ~10 year old Civic, going down a hill. But not with the battery disconnected. Maybe I'll try it. Not now, though. Edit: And upon reflection, maybe not. Because I'd have to pay someone to reset the computer. Edit: But wait a minute. If the vehicle is moving downhill, and you engage the clutch in…

Careful! Shutting off the ignition will lock the steering wheel on older cars.

Re: When I Took My Zipcar Into the Wilderness

#74

Post by oh_sigh »

Nextgrid wrote: post #70
xzmmd wrote: post #66

Earlier quoted context omitted.

You're justifying acting like an asshole.

No I’m trying to justify using the product as it’s advertised. Otherwise it’s too easy to just falsely advertise something and ban the people that manage to figure out the catch.

You said you did it a few times. How often do you have to do something with negative consequences before you learn you shouldn't keep doing it?

Re: When I Took My Zipcar Into the Wilderness

#75

Post by oh_sigh »

PetahNZ wrote: post #28
bt848 wrote: post #27

Earlier quoted context omitted.

The bit about the cell phone discharge seems pretty unlikely. A charged car battery has at least 2MJ of stored energy. GSM in its highest-power mobile station state draws 800mW. Add maybe another 150mW for the GPS, call it 1W total. The battery should power such a phone for weeks. You should be able to smell-test this fact by considering that your mobile weighs nothing and runs all day whereas a car battery weighs 20…

Anecdotal, but if I leave a USB charger plugged into the cigarette socket, without even anything plugged into the usb, it drains my battery overnight.

If it's not a car from the 80s there may be a fuse you can add/remove which converts your cigarette lighter from always on to only when engine is on. Check the back of your car manual.

Re: When I Took My Zipcar Into the Wilderness

#76

Post by crankylinuxuser »

oh_sigh wrote: post #74
Nextgrid wrote: post #70

Earlier quoted context omitted.

No I’m trying to justify using the product as it’s advertised. Otherwise it’s too easy to just falsely advertise something and ban the people that manage to figure out the catch.

You said you did it a few times. How often do you have to do something with negative consequences before you learn you shouldn't keep doing it?

Other than being told its a signal issue, how do you determine that? IoT crap rarely, if ever, actually communicates with the user about error conditions. You usually find out shit 'no workey' after the fact.

There's a lot of articles and twitter feeds. Go look up the "Internet of Shit". There's a reason why it's called that.

And Zipcars are no exception, evidently.

Re: When I Took My Zipcar Into the Wilderness

#77

Post by jacquesm »

2rsf wrote: post #49
dx034 wrote: post #39

Earlier quoted context omitted.

Honestly, the ban sounds justified to me. If you know that parking in the garage will lead to a 50% probability of them having to tow the car, repeating this is just unnecessary. It would obviously be better if they could handle such scenarios but ignoring a known limitation to incur cost to others (since you have no advantage as you also can't use the car in this scenario) sounds wrong to me.

> Honestly, the ban sounds justified to me based on the story above I agree, knowingly (and after a few occurrences you should understand there's a problem) damaging the service should lead to a ban or at least a warning.

No, it should lead to someone fixing the problem. The customer centric thinking in this thread is amazing.

Re: When I Took My Zipcar Into the Wilderness

#78

Post by makomk »

dTal wrote: post #55
msbarnett wrote: post #30

Earlier quoted context omitted.

Your smell test is a bit misleading in that most car batteries have a drastically lower energy density than Lithium Ion cells. There’s still a lot more energy in the car battery, of course, but not by nearly as much as a naive comparison of the weights would suggest. If it had the energy density of your cell phone, the lead acid battery in your car would only weigh 5 or so kgs. Your cellphone will also last a lot les…

I also seem to recall that standard car batteries respond poorly and inefficiently to trickle-discharge, being designed mainly for providing a lot of amps over a short period. Providing long term off-grid power is what deep cycle marine batteries are for, and they are a separate product.

As far as I know standard car batteries are fine with this kind of trickle discharge. Where they fall short compared to deep cycle batteries is providing a more substantial current (think tens of amps) over a prolonged period of time.

Re: When I Took My Zipcar Into the Wilderness

#79

Post by [deleted] »

karlp wrote: post #65
bt848 wrote: post #34

Earlier quoted context omitted.

OK, here's another test. A common way to end up with a dead battery is to leave the lights on overnight. The lights on a car draw over 100W (standard halogen headlights and incandescent tail and marker lights). But you can leave your lights on for hours and still start the car. Therefore it stands to reason that the same battery could power a GSM radio for hundreds of hours.

This assumes the battery is fully charged, if it's cold or if the battery is slightly defective, it could be a lot less than full charge.

[deleted]

Re: When I Took My Zipcar Into the Wilderness

#80

Post by pmontra »

isostatic wrote: post #50
rebuilder wrote: post #42

Earlier quoted context omitted.

I haven't used any of the services you mention, but an on-line rental service I have used has a simple system: they unlock the car remotely when you start your rental, and the key is in the glove compartment. You may run into issues starting your rental, but lack of connectivity won't stand you in the middle of nowhere. Is there a particular reason these services can't just leave the keys in the car? Theft?

If the car has no signal, how is it unlocked?

Good question, but if there is no signal how could the previous driver have locked the car? Similar services I'm using don't let me end the rental if there is no signal, simply because either the car or the shop on my phone can't talk with the server.
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