Maybe you should try to find out what using your data / battery through Data usage or Battery usage in the settings, and find out the real culprit on this case. Previously i found facebook was used up most of my data and i had switch it to sync the notifications at 4 hour once instead of push notifications, this do help me to save some of my battery also

sometimes when you're at some place with signal very low, it might tend to use more battery than other place with full signal. As for me, the phone was able to last me from 8am - 11pm with 10-20% left everyday.