To "charge" a device means to plug it in and fill the battery. You can use the word "charge" with "battery" or you can use it with the device itself:

Don't forget to charge the camera!

When the battery is full, you say that the device "is charged":

A: Is it charged?

B: Yep!

Charging a battery that has run out of energy can also be called "recharging" it:

I need to recharge my phone.