That sounds kind of weird, removing the battery will cut the power.
Well you could try a 10 second press of the reset button at the back (there is a soft reset and and hard reset - 3 second being a soft reset), and hold the page turn button for the firmware update.
Have you looked at this thread
https://www.mobileread.com/forums/showthread.php?t=91571 and tried the holding the power button and left page turn button`