This sounds like a Windows problem.
It's not a Windows problem I don't think. Windows is just going on what the electronics are telling it is the remaining charge in the battery.
I can tell Windows to do whatever I want it to do, and it does it. If I want it to wait until it's down to 2 percent and then go into sleep mode, great, it does that. The problem is that the battery isn't being honest with regard to what "2 percent" really is.
If it were a Mac it would say something like 15%, change to 14% and then suddenly shut itself off well before you expected it to.
I'm having the
opposite problem. If I turn off the feature that automatically sleeps it when the battery gets low, then I can watch the gauge and it shows it draining all the way down to zero. Then the thing still lasts for another half an hour before actually going poof.
Am I right in assuming that the "gauge" in question is in the electronics attached to the battery?