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Comment by rtpg | Hacker News Reader

I remember a couple of threads where someone would come in and mention how phones make terrible servers because they basically default to overheating and just start failing terribly if you try to leave them on... wonder if people have found ways around this issue.

Would actually be pretty amazing if you could just mount like 5 or 10 garbage phones into a thing and it could smartly give you a super slow but reliable server setup. Reuse!

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The biggest issue I've found while trying to do this is a very high rate of battery failure while plugged in 24/7 under load. 4/5 phones I've done this with have become spicy pillows in the 1-2 year timeframe. They were all Samsung or LG devices, so not complete bottom of the barrel garbage batteries either. IME if you need a cheap server, a used enterprise micro pc has a much lower chance of potentially burning your house down, can be found on ebay for literally $30, and can be easily stuffed full of ssds.

FWIW, Samsung batteries explode even if you don't use them as servers, and in fact it was an issue with their batteries being trash (I think I remember it being that they had been contaminated with metal filings, but I might be entirely misremembering the verdict).

https://www.youtube.com/watch?v=OfM0GqsIB6c

I wanted to learn some details about that story (I heard about it back then, but never digged deeper).

Your link seems to lead to some kind of shady video clip portal.

Was that intended? If so, is there a textual version as well? Video clips seem to be a poor medium for most kind of actual information transfer.

Did you try direct wiring to bypass the battery?

E.g. https://www.instructables.com/Power-an-Android-Phone-Without...

Nope, and that definitely would have helped, but I bet 99% of people looking to use an old phone as a server aren't going to do all that either.

With most new phones not being designed to have swappable batteries like the S4 anymore, could this be modified by replacing the cells with a capacitor and then powering the phone from USB?

Would be worth an experiment potentially but it’ll depend on where the protection circuitry lives. A modern BMS chip is relatively complicated and will freak out if the attached “battery” is doing this that wouldn’t be safe for a LiPo cell (eg a capacitor will happily drain to 0V but a LiPo drained to 0V has probably been destroyed)

> 4/5 phones I've done this with have become spicy pillows in the 1-2 year timeframe.

In their defense, that kind of usage is not what they've been designed for and tested against.

I just am thinking about how many phones you can find all over the place. And that tiny footprint... just so tempting.

I want to respond with a Beowulf cluster joke.

Then I remembered this isn’t slashdot and it isn’t 2001.

Now I’m reminded of how old I’ve gotten.

Just remember, BSD is dead now.

Slashdot is where I found out about 9/11. I got up one morning and the NY Times (which I usually read first) wasn’t loading. Neither was CNN. After one or two more news sites, I shrugged and went to Slashdot, and that was where I saw the news.

Thanks for the memory lane trip, mate. Yep, we’re old.

I saw a throw away container for old phones in a zoo and couldn’t resist to pull out some old bastards.

Sounds like even more phones are needed, with a control plane that can let them sleep regularly!

I plugged in an old iPhone SE into the Lightning port on a nice speaker and locked the screen to Spotify -- with auto-brightness it worked fantastically.

Until it also turned into a spicy pillow after about a year and a half.

Really wish there were some kind of system preference to run off wired power only and just not charge/discharge the battery at all.

Some older iPhones can be powered by a $30 "battery simulator" used by repair shops, https://youtube.com/watch?v=jTtGwKS7S0c &

DT880 (for specific older iPhone models, there may be other products for newer phones): https://witrigs.com/products/dt880-mobile-phone-current-main...

I've tried but I don't get the spicy pillow reference. Did it catch fire? Or the screen die?

I believe it's a reference to the look of a failed LiPo battery: it puffs up and looks like a pillow, but if you puncture it fire spews forth.

Reddit first came up with the phrase "spicy pillow" to describe that combination.

Which used enterprise micro PC on Ebay for $30 would you recommend? Trying to sort thru the trash and other options.

OP probably refers to Lenovo ThinkCentre mini PCs; they're well made, quite expandable and cheap, but if you can't find any, check out used Chromeboxes. They can be unlocked and reflashed with Coreboot in a single step, which makes them more secure aside allowing the native install of your OS of choice. Hardware quality is usually very good.

More info here: https://docs.mrchromebox.tech/

Chromeboxes aside, I've installed various Linux distros on different MiniPCs and the outcome has always been great; the only caveat is to check if your particular model does like to be used without a monitor. In some cases they didn't and refused to boot, but I solved by connecting on the HDMI port one of those cheap "virtual monitor", "dummy monitor", etc. dongles sold to perform this exact function.

Sibling comment has good suggestions. I personally like Dell Optiplex models, e.g. 9020. Looks like right now the best you can do is about 40-45 shipped for a complete one, but I've snagged about six in the last year or two for 20-35. They come and go. Beware of sellers posting the same thing for 100+; they're worth max 50.

https://www.parkytowers.me.uk/thin/hware/hardware.shtml

From the above site I landed on the Dell WYZE 7020 / Zx0Q... Some models of which have 4 cores (also accidentally bought a dual core version), supports 16GB DDR3, are passively cooled without a fan, and cost me about $50 on eBay (add $20 for a 16GB RAM kit to bring the total to $70)

It's about as fast as a Raspberry Pi 4, and has been great for letting me spin up a docker container to play around with a database or a message broker or what have you.

I limited my search to only fanless designs though; if you are fine with fans then I'm sure there are more performant options out there.

What does spicy pillow mean

The battery in the phone blows up from flat to pillow shaped. It’s chemically spicy inside.

I haven't tried this for an always-on phone, but ACCA[0] grants fine-grained control over battery charging behavior. An ideal state of charge would be about 40%, with battery idle mode turned on so the phone draws power directly from USB without using the battery.

Note that this requires root, but you'd probably want root for all but the simplest file server setups anyway.

[0] https://f-droid.org/packages/mattecarra.accapp/

AccA is my first app install (after F-droid I guess) for rooted phones.

It should be a standard feature of all phones to be able to control charge to maximise the useful life of the device if they're not going to make batteries removable.

My guess is that the issue is more related to the constant high temperatures rather than the battery state of charge, which this wouldn't assist with.

Both heat and high state of charge wear the battery faster, but the combination of both is far more destructive than either alone. Keeping the battery at 40% charge will greatly increase its lifespan.

A typical Li-ion cell stored at 60C and 40% charge for one year will still have 75% of its capacity, while storage at 60C and 100% charge will have it down to 60% capacity in three months.

https://batteryuniversity.com/article/bu-808-how-to-prolong-...

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