My laptop is Lenovo IdeaPad Z50-70 (59-429623). i bought it in Dec 2014. Now if i start my laptop and leave it as it is, it shows a good battery backup of 3-4 hrs. But if i run any medium or low end applications like vlc, chrome or adobe even, the battery starts draining rapidly and then lasts only for an hour or two when full charged. What should i do?