[myself248]

Funny, I just found myself posting this comment: https://www.udoo.org/forum/threads/why-the-narrow-12v-5-volt...

It's only been a few days but nobody's responded yet telling me not to, so I'll get on with the experimentation shortly.

And yeah, as I just showed in another comment, I just take "18v" drill packs, which are 5-series strings of lithium-ion and thus range from about 15 to 20 depending on their charge range, and pipe 'em directly into my thinkpad's input jack. It charges quite happily until they get down to about 17.5v at which point the battery doesn't have a ton of charge left anyway, and the thinkpad neatly stops drawing current and avoids flattening the pack.

https://i.imgur.com/hYRje5h.jpg

I run the exact same arrangement, with a different plug tip, into my Evolve III Maestro. It comes packaged with a 12v brick but it's experimentally happy between 10.4 and 25.1 volts, so 15-20 is right on the money.

https://www.reddit.com/r/linuxhardware/comments/tk6hdp/evolv...

[consp]

Some laptops with changable batteries have 4/6/9 cell variants. I know Lenovo has them in the 11-14v nominal (from my head) range, 4s/3s2p/3s3p, so the lower voltage spec for the DC/DC converter might even be lower than 12v.