Ok this just happened to me. I had just done a flight roughly 8 mins 6000ft trip. Landed. Went from my front yard to my back yard then relaunched was about 1700ft out battery was 61% and all the sudden I got a critical battery voltage error pop up for about 3 seconds, the app beeped then it went away. I immediately turned the bird and headed back Full speed dropping attitude also landed in my backyard about 54% never saw the message again. I checked the battery info center everything said normal voltage all 4 cells were even also. This battery is one of my brand new ones maybe 1 flight in it prior. Really tripped me out. Is there a way to go back and see a log of error messages ?