Battery complications

Tweet

While buying laptop, manufacturer told me that this laptop has 5+ hours of battery backup. I started using it, frequently keeping it on SLEEP mode. My friends say that, SLEEP mode affects battery backup of the laptop. So, I wanted to know, to get a perfect battery backup, my laptop should be on SLEEP mode or everytime my work is over, I should shut it down??? Help me friends, I don't want to ruin battery of my laptop...