There are different batteries that a receiver can have.
Internal and external batteries for example.
There are batteries that need to be replaced after they run out (external). However, the batteries that go into a receiver are not cheap, luckily they are often available from a local dealer and from various web shops.
There are also receivers that work on multiple batteries. So when battery 1 is empty, you can still continue on battery 2 or 3 while putting a new battery in the place where battery 1 should be. This we call a Hot-swappable Battery. This ensures that the project does not temporarily stop and you can continue your survey
There are also receivers with battery systems that can be charged by means of a USB cable. This way, you do not need to buy a new battery and you can simply plug the receiver into the charger (internal).
So depending on how long you have to use the receiver per survey and how often you will need the receiver, these are options to think about.
Let us know what type of battery you prefer in a receiver, and why!