Matching of Passive Magnetic Energy Harvester Clamped on High-Currents-Carrying Conductor to Rechargeable Li-Ion Battery

The paper focuses on passive magnetic energy harvester (PMEH) clamped on high-currents-carrying conductor, feeding a rechargeable battery. It is acknowledged that the power harvested by a PMEH terminated by constant voltage load (CVL) is maximized under unique (optimal) load voltage value. On the other hand, terminal voltage of practical Li-Ion batteries may rise substantially during charging process. When such a battery is connected across PMEH output terminals, load voltage would certainly drift from the optimal value. Consequently, the paper investigates the conditions for matching a PMEH to rechargeable Li-Ion battery, allowing to maximize the energy delivered to the battery under expected terminal voltage variation. Experimental demonstration of PMEH capable of charging a 350Wh Li-Ion battery from 200ARMS-carrying conductor at 115W rate validates the revealed findings.