PURPOSE: To attain portable operation of a portable device for a long period in the communication equipment comprising the portable device having a basic communication function and a stationary device 30 having an additional function and to which the portable device is removably fitted.

CONSTITUTION: A battery device 50 incorporated with a large capacity battery 59 is provided with mechanisms 55, 56 supporting a portable device 10 removably and a connector 51 connecting to a connector 21 of the portable device 10. The battery device 50 is compatible with a stationary device 30 with respect to the mount of the portable device 10 and the power supply circuit of the portable device 10. When the portable device 10 is loaded to the battery device 50, the operating power supply is supplied from the large capacity battery 59 to the portable device 10 through the connectors 21, 51.