Flaky Garmin 810?

[ls1togo]

I've owned several Garmin GPS computers and my current one is a Edge 810 which over the last year has been great. Recently on clear or only minimally cloudy days with at least a 55-75% battery and it just shut off!..I would turn it back on and the acquisition of the satellites was erratic...and of course, had lost the data that had been recorded...
I've read that some have attributed this to the battery....Any ideas?