Macbook Pro Retina Battery Decrease

Hi all!

I have a Macbook Pro Retina 13 inch late 2013 model (i5/8gb/256gb), running OSX El Capitan, and I have been having issues with my battery of late.

I have only just received the Macbook back after having a faulty fan replaced (thanks Apple), however since I have noticed that my battery life has decreased from the 10-11 hours I used to get, to between 6-7 or so hours.

So far I have tried resetting the SMC, and NVRam (or whatever its called), I have disabled flash, wiped the computer and started from scratch.

The computer is saying Safari is using significant energy, and in activity monitor it is fluctuating between 7 and up to 18.

The computer is estimating a battery life of 7 hours at 85% charge with nothing open other than this page. I have also tried cycling the battery and the cycle count is only at 350 or so.

Any tips for getting the battery life I used to take for granted back?

Thanks

Callum