Hi, I just bought my new laptop Asus ROG gl503VD. But within in a span of 40 mins the battery life goes down. I tried to back the product to the store where I purchased it. But they said that there's nothing wrong on my laptop battery, after they burn test. So i WOULD LIKE TO ASK IF WHAT CAN I DO TO EXTEND THE LIFE SPAN OF MY BATTERY? EVEN THOUGH IT IS FULL CHARGED AND I DIDNT USE IT, THE BATTRY STILL GOES DOWN TO 0.. THANKS. HOPE SOMEONE WILL HELP ME!