It will depend on a lot of factors, but certainly battery life is not a strength of the S6 and S6 Edge.
I've got three phones running now and clearly the S6 Edge is the most "challenged" of the group. Part of that could be carrier signal issues, but generally it reminds me of the original Nexus 5.
Certainly you'll want to keep charging gear nearby. Good news is that it does have wireless charging built in (though it doesn't come with a wireless charging device, though they aren't that expensive. It also supports rapid charging, so you can get it back to 100% pretty quickly.