OK, this has me stumped:
I've had this mini9 since the beginning (what is that 4 years or so now?) and the battery started lasting shorter and shorter (to be expected). Bought an aftermarket ext. life battery. First one wouldn't charge, sent it back. Second one was a little better - it would stop charging at random "% full" readings, but in general it would charge to over 70% and last for hours. Then, all of a sudden the mini9 wouldn't boot from battery, but if I plugged it in to boot (first flash of light i could unplug) it would still last for hours. And charged fine. This got to be a pain, so I went back to the original battery - it boots every time even if not plugged in. But now the original won't charge (it won't go down if plugged in, but never goes up). Any ideas? I suspect the replacement battery just wasn't engineered well, and the original is finally dying, but I don't want to buy a 3rd if it's really the laptop that is dying.
Thanks for any thoughts.