Clara HD sometimes unresponsive (battery?)

[Canuck_in_Japan]

I don't know if this has occurred with anyone else before but I've sometimes found that I'll go to wake up my Kobo Clara and nothing happens when I hit the power button. I can push it as often as I like but there's no reaction. If I hold the button it will start to restart but it will stop in the middle of the three blinking dots. It's like it's restarting but then running out of power. The only way to fix it is to plug it in and then it will automatically turn on. It seems like it would be a battery issue but I knew I still had battery left, and sure enough when I plugged it in this afternoon and it turned on it told me it still had 37% battery power. Is it possible that the battery indicator is giving the wrong battery percentage? This occurs from time to time and I can't figure it out.