[dspillett]

> Yes, or servers.

Though take care with the batteries. Left plugged in 24/7 some turn a bit fiery after a time, or just fail in a way that takes out the device at an inconvenient time.

Some remove batteries from laptops used this way for that reason, though that throws away the built-in-UPS benefit. Another option to mitigate the issue is a timer switch that disconnects power for an hour every few, this works well while the battery still has enough life in it at all.

If you are a smart-home-hacker you could rig a controlled plug up to the battery state so you can flip power back on/off when the battery hits a certain level, rather than relying on a fixed time period, though I'm unsure whether that is worth the effort in terms of preventing potential faults and preserving battery life (IIRC charging up to 80-to-90% and discharging to ~40% is considered optimal for prolonging the useful life of modern batteries?) or if it would “just” be an interesting nerd project.

[waselighis]

I'd argue just recycle the batteries and have a proper UPS or backup generator. If the batteries are still good, resell them to people who could actually use them. Otherwise, drop them off at a recycling center. Using them as servers, the batteries wouldn't be doing anything 99.9% of the time, and the constant charging and heat would simply kill the batteries. Simply wasteful.

[scratchfi]

Fun fact about HP pavilion laptops: They need the battery installed to preserve secure boot bios information. Otherwise, it's a complicated set of post interactions to do a one-time reset.