It has a built-in rechargeablebattery charged via USB.
Times, Sunday Times (2009)
The receiver can be run off the mains or its rechargeablebattery, and you can use a clip to hook it onto your belt.
Times, Sunday Times (2012)
Definition of 'battery'
battery
(bætəri)Explore 'battery' in the dictionary
countable noun
Batteries are small devices that provide the power for electrical items such as torches and children's toys.
Definition of 'rechargeable'
rechargeable
(riːtʃɑːʳdʒəbəl)Explore 'rechargeable' in the dictionary
adjective [usually ADJECTIVE noun]
Rechargeable batteries can be recharged and used again. Some electrical products are described as rechargeable when they contain rechargeable batteries.