A trickle-charged RFID device includes a main antenna receiving wireless interrogator signals from one or more RFID readers, a power harvester connected with the main antenna to obtain power from the wireless interrogator signals, and an intermediate storage device connected to the power harvester to collect trickle flows of unused power harvested from wireless interrogator signals received by the RFID device that lack an inquiry for the device. The RFID device further includes a primary storage device, into which the intermediate storage device discharges its collection of trickle flows of unused power when the collection reaches a predetermined threshold level, which recharges power lost from the main storage device. The intermediate storage device can include one or more capacitors including super-capacitors, and the main storage device can include a rechargeable battery, such that the effective life of the main storage device is extended from the collected trickle flows.