The Z6 and Z7, plus their first updates, used the EN-EL15A or EN-EL15B batteries (the Z6 III uses the EN-EL15C). At the moment, there are no third-party EN-EL15B batteries available, which means that there are no third-party batteries that support in-camera charging on the Nikon Z5, Z6, Z6 II, Z7, and Z7 II. However, there are third-party batteries that work like Nikon EN-EL15 or EN-EL15A batteries, which the Z5, Z6, Z6 II, Z7, and Z7 II can use normally, but not charge.
With the Z5, Nikon introduced a new version of the EN-EL15, the EN-EL15C (see next page on this site). This new version has a higher capacity (2280mAh versus 1900mAh). This new version of the battery can be used with the Z6 and Z7 (and other Nikon cameras that use the EN-EL15), and provides more capacity than the EN-EL15B supplied with previous cameras.
Quite a few chargers exist for the EN-EL15 batteries (and work with all versions). I like the dual battery chargers that have level displays.
And you'll want something to carry your batteries in (and cards) in some sort of case (to protect the contacts from being accidentally being bridged).
If you don't like the Nikon MB-N10 Battery Pack, there are low cost third party options that include both a built-in shutter release and wireless control, such as this one:
- MCOplus Multi-Battery Power Pack
