I understand the notebook is powering off when the battery gets to 50%.
I would recommend trying the steps listed by DavidPK in the following thread.
http://h30434.www3.hp.com/t5/Notebook-Hardware-e-g-Windows-8/Battery-shuts-down-when-it-reaches-50/m-p/531925
I would recommend trying the steps listed by DavidPK in the following thread.
http://h30434.www3.hp.com/t5/Notebook-Hardware-e-g-Windows-8/Battery-shuts-down-when-it-reaches-50/m-p/531925