There is a huge difference in the
batteries. I'm assuming that you are referring to 18650 batteries in particular. I suggest that you read through these links:
Battery Basics by Baditude
Mooch - Picking a Safe Battery
You could also go through
@Baditude and
@Mooch blog posts. Both are very respected members here who have put a lot of time and energy into helping the community to understand the batteries that we use.
Bottom line, though, to answer your question. Sony VTC4s from a reliable source such as Orbtronic or RTDVapor are the most highly recommended batteries.