What problems may cause the battery not to charge or Ubuntu to report only a 6% charge?
The AC Adapter is warm, emitting a high-pitched buzzing noise, and says "INPUT: 100-240 V ~1.5A / 50/60HZ", "OUTPUT: 19.5V (solid overbar, dotted underbar) 4.62A".
I just bought a replacement battery from Yahoo Shopping Japan; came about 40% charged. Followed the instructions to discharge it down to 10%, wound up using it past then, tonight plugging it in to fully charge as directed, using the computer while charging it.
Lubuntu 16.04 reports the battery as 'Charging', but it has been at 6% for 30 minutes, so it appears not to be charging. Dual-booting into Windows 7, it says "7% available (plugged in, not charging)".