NOTE:A New Battery can not only fix your lack of power but can also fix your overheating problem in some cases.
Samsung J1 Battery
Samsung Galaxy J1 Battery EB-BJ100BBE EB-BJ100CBE
SAMSUNG GALAXY J1/J100 BATTERY
The brand new 3.85V 1850mAh 4 Pin Li-on Original Battery is compatible with Samsung Mobile Phone Models:
Samsung Galaxy J1 SM-J100 J100
Samsung J100F, J100FN, J100H, J100H/DD, J100H/DS, J100M, J100MU
Compatible With Samsung Part Numbers:
EB-BJ100CBE (4pin)
EB-BJ100BBE (4pin)