We've purchased no-name replacement batteries for a couple of notebooks here.

The first attempt was for an IBM Thinkpad, years and *years* ago. The new battery worked, but would only charge when the notebook was actually powered on and running. Weird.

Much more recently (Edit: one year ago), we bought a no-name battery for an old Dell notebook. Cheap, works perfectly. Zero issues.

I write the Thinkpad incident off as an anomaly. These days (since 2002, at least), with more standardized notebook chipsets and less trickery/hackery in them, I'd go no-name for any replacement batteries.

Heck, if I can get the battery shell open, I might even just replace the cells inside the factory battery pack.

Cheers