The present invention relates to a battery module for wireless exchange of data and power between the battery module and another device of a system, in particular of a patient monitoring system, to which said battery module is coupled. The battery module comprises a sealed housing (93), a battery unit (91) for storing electrical energy, a data storage unit (94) for storing data, and a connector (95). Said connector comprises a data transmission unit (96) for transmitting data to and/or receiving data from another device of the system having a counterpart connector and a magnetic coupling unit (92), separate from the transmission unit (96), for transmitting power to and/or receiving power from another device of the system having a counterpart connector by use of inductive coupling. The battery module is configured for mobile use and for coupling with different devices of the system.