A system includes a first plurality of secondary devices, each secondary device of the first plurality of secondary devices including a first wireless transmitter and a battery monitor integrated circuit (IC). The battery monitor IC is configured to obtain battery data from at least one battery cell, and the first wireless transmitter is configured to wirelessly transmit the battery data. A first primary device has a second wireless transmitter wirelessly coupled to the first wireless transmitters of the first plurality of secondary devices via a first wireless network. A second primary device has a second wireless transmitter. The second primary device is configured to detect a fault with the first primary device and, in response detection of the fault, to establish a second wireless network with the first plurality of secondary devices.