Beaglebone Blue doesn't want to power on by battery


My BeagleBone Blue was working fine with battery before (able to charge, able to power on by only using battery) but now it doesn’t want to charge or power on with only the battery plugged in anymore.

The battery are fully charged, measured 4.13v each cell by using multi meter and 8.28v on the two outer pin, but the BBB doesn’t power on when I plug the battery in, the LED G, R, ON, 75 flash briefly and dim when I plug the battery in, it flash around 8-12 times and it stop flashing and nothing happen, when I press power button then it flash once (dim and briefly as before) but nothing seems to change.

When I power it on via DC jack and plug the battery in, using rc_battery_monitor I get pretty accurate reading of voltage of each cells but it doesn’t charge the battery, the voltage stay at 3.5v on the battery that I’m trying to charge and doesn’t change after 6hrs of charging so I think there is a problem somewhere with the board.

Has anyone experienced this before?