How long does the battery last on the NVW-600CMB or NVW-AS4KCAM cameras?

Answer: Depends on the usage — it can last from a few days to a few months.

Frequent motion trigger or remote access will drain the battery much faster.
If the battery drains quicker than usual, visit this article

You can also add a Swann Solar Panel which keeps the battery topped up and can almost remove the need for any charging at all!