A battery sharing method to increase the service life of the batteries of PMR terminals having important uses, such as the terminal of the head of a group such as the police, firefighters, or the like, is disclosed. The technique is based on the detection of neighboring networks and/or neighboring nodes. The detection is facilitated by reiterating a selection (or reselection) of cells and a handover (HO)/vertical handover (VHO) procedure, while relaying and coordinating transmission and reception. The aim of the techniques is to improve communications as well as the duration thereof, in order to enable improved management of the battery of each terminal and to broaden coverage in areas that are not served by a network.