Is there any difference between the iPhone 4S and 5s battery?

I currently own a 4s and was thinking of upgrading to the 5s

Yes.

Bigger battery in the 5s than the 4s.

Yes. 5s is having good battery life compare to 4s

Yes the 5s battery is a little better but both are good the 5 s lasts mostly all day I don't need to charge it up until that night.

5S is far better, thats true on all the 5S hardware all around.

Your wait until September to see exactly what the iPhone 6 is like.

Welle there's nothing really new on the 5s besides the fingerprint scanner. I'd recommend the LG G2 or Galaxy S5