"<i>When disagreeing, please reply to the argument instead of calling names. 'That is idiotic; 1 + 1 is 2, not 3' can be shortened to '1 + 1 is 2, not 3.</i>"<p><a href="https://news.ycombinator.com/newsguidelines.html">https://news.ycombinator.com/newsguidelines.html</a>
I have multiple devices with lithium batteries plugged in 24/7. A kindle that I use as a display for example. So far nothing exploded. If exploding kindles were a thing I guess I would have heard.
I have not had anything explode, but I have had Macbook batteries expand on me on two separate occasions to the point where the case was visibly warped. Both times I was away from home, so it was extremely inconvenient.
you use a kindle as a display?
The fact that they can doesn't mean they will.<p>On older devices the controller might make some assumptions that holds true with a new battery, but very much doesn't with an old and worn one.<p>My Macs have all been sensible about it, but I've seen Windows machines with batteries that just died from being plugged in all the time not even 10 years ago. Even if that specific instance was just a bad battery and not due to a charge controller, I have no faith in Random Windows or Android OEM Number 582 doing this correctly.<p>For devices that are fixed, I'd prefer to eliminate the potential of there even being a problem in the first place.
There’s basically zero risk for these cell phone batteries outside of freak accidents, speaking as someone who who’s been building packs since pouch cell Lipos first started coming out for model airplanes back in 2008/2009.. That’s because in a single cell configuration, there’s no way for the charge controller to run up an imbalance and overcharge one of the cells.
I somewhat agree with you. As my last comment suggests, I have a lot of experience running phones as AP’s including phones with dual cell configurations.<p>Where things go off the rails is situations where extreme heat can be present (shoving phone in direct sunlight in window with hot climate is a bad move) another thing they don’t tolerate well and people don’t talk enough about this is deep discharging the batteries frequently. This causes a breakdown of the SEI membrane and makes it so future recharging generates more heat and gas. This will cause expansion and might cause a short/failure if poorly designed (galaxy note 7).
fwiw I’ve used 24/7/365 plugged in phones as AP’s in multiple locations for a decade or so now, never had an issue. Past few years I use the battery threshold to set them to 70% charge and they don’t move from this for months at a time.<p>What roasts the lifetime of my laptop batteries is compiling with gentoo, but again never an issue with catastrophic failure and I have 20+ years of experience with that as well.
Three times I've been lazy and set up an old phone or tablet as an always-plugged-in stationary device without excising the battery, and that has produced two spicy pillows and one completely dead battery (phone wouldn't even boot when plugged in, until I replaced the battery). Granted, these were all 5-10 years ago, but I do not trust the batteries and their controllers in these devices.<p>Nowadays if I want to leave a device plugged in I crack it open, remove the battery cell, solder on a power supply and capacitor, and then do the nonsense with rooted Android to keep it from shutting itself down.
That's silly. Batteries don't like to be kept at 100% all the time, not unlike your lungs which doesn't want to stay filled all the time (which is uncomfortable for your muscles even if you ignore the carbon dioxide).<p>e.g.: MacBooks discharge the battery down to 80% by using the battery even if it's plugged in by citing "Rarely used battery", and keep the battery at 80% for at least half a day, then charge it again.<p>Li-ion is an adversarial chemistry. You need to take care of it or the battery bites back by puffing up or losing capacity very fast, or becoming an indoor firework.
I've gone through a dozen or so LiPo-utilizing portable devices at my property in the Mojave desert. All it takes is a single season for many of these batteries to swell up to such an extent the enclosures split open.<p>Ostensibly they contain charge controllers and temperature sensors, yet they're unable to prevent this outcome when the ambient temperature exceeds 110F day after day while the device stays on in a hot attic w/usb-c pd connected.<p>Fortunately I haven't had any burst into flames yet, but after a few years of seeing this pattern repeatedly I stopped deploying anything containing LiPo batteries at the property.<p>YMMV - but IMHO it's prudent to exclude these batteries from such unattended, powered 24x7 devices.
Most can, but you do get reports that sometimes they don't, and better safe than sorry.<p>I'd guess it would have more to do with heat, though.
For how long?
I have a fire tablet I hucked into my wall to use as a home assistant console.<p>It's been in there for 5 years now, always plugged in.
I've been using an old Pixelbook for 3 years that I had laying around for an always on Home Assistant control panel (but with adaptive dimming that defaults so extremely low brightness to reduce heat until approaching it).<p>I noticed a few months ago that the battery has started to significantly swell pushing the back panel apart, but I haven't worked up the motivation to try removing it yet. From what I can ascertain from user experiences, it actually does boot sans battery but haven't confirmed, it would be awesome if that worked and would probably give me 5+ more years of usage.<p>So in my case, data point is that 3 years of 24/7 use/charging of an old laptop/tablet was enough to push it over the edge and finally swell. It's really a shame how so many otherwise usable devices that could be wall mounted turn into e-waste because they won't run without a battery. With USB-C PD a well-designed device should be able to get whatever power is needed on demand but manufacturers don't really have any incentive to future proof for the .01% of users like me who would benefit.
I have a Samsung tablet in a non-flammable container waiting to be disposed of after being mostly plugged in for 3 years then suddenly swelling quite alarmingly. YMMV.
Right, but, this is just a single data point anecdote, right? Let’s say for same of argument that there is a 5% chance of overheating in five years - and another sub-percentage where this causes a fire, depending on where it is plugged in.<p>95%+ of people would report “zero problems here, all concern is overblown”.<p>Safety doesn’t work that way?
> <i>I have a fire tablet I hucked into my wall to use as a home assistant console.</i><p>OK, but "fire" is right there, in the name.
Until the heat death of the universe, and a couple beyond.