My Y510p also has the battery drain problem. I set the in the Battery Management to optimize for battery health, which charges to 60% and it will stop charging. When I completely turn off the computer (with wake-on-lan and usb charging disabled), it took around 2 weeks to lose all the 60% of the charge. I've tried to remove the battery for 1 week, when I replugged the battery in, it shown no battery lost at all, thus 60%. So, it should be problem of the laptop electronics / bios problem, not the battery itself.