How can I improve my battery life? I was getting 4-5 hours on Windows 8, maybe 6 if I tried for it.  With Freya I'm only getting 1.5 hours.  Why such a drop and how can I fix it?  

Processor: quad core AMD A6-6310 APU w/ AMD Radeon R4 Graphics

Memory: 6.7gb (which is weird because it is an 8gig laptop, and shows something like 7.7 gigs when it was running Windows)

Graphics: AMD.  Mullins Radeon APU A4-6000 w/ R2 Graphics

Storage: 976gb

It is a entry-mid range Lenovo laptop