A rack for securing containers includes a plurality of bays into which one or more containers are received. The ionically conductive clay additive is modified to include halogen atoms to increase the negative charge density of the additive and improve its performance in the electrochemical cell. The mobile network establishes, for the plurality of wireless devices, a single service bearer over the mobile network and associates the single service bearer with the group identity and with a single PDP address for the plurality of wireless devices. Alternatively, additions and changes are identified by a comparison of a first file with a second file containing the additions and changes.