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Abstract Wireless power transfer (WPT) has received increasing attention primarily as a means of recharging batteries in the last few decades. More recently, magnetoelectric (ME) structures have been investigated as alternative receiving antennas in WPT systems. ME structures can be particularly useful for small scale devices since their optimal size is much smaller than traditional receiving coils for a given operating frequency. WPT systems using ME laminate receivers have been shown to be helpful in wirelessly powering various sensors and biomedical implants. In recent years, a large number of studies have been conducted to improve the performance of ME composites, in which various configurations have been proposed, along with the use of different magnetostrictive and piezoelectric materials. In addition, many efforts have been devoted to miniaturizing ME devices. An essential obstacle to overcome is to eliminate the need for a DC bias field that is commonly required for the operation of ME structures. In this review paper, we will discuss the basic principle of ME effects in composites, materials currently in use, various ME receiver structures, performance measures, limitations, challenges, and future perspectives for the field of WPT. Furthermore, we propose a power figure of merit which we use to compare recent ME WPT research papers. 

Abstract The frequency dependence of the maximum output power and efficiency of two wireless power transfer systems (WPTSs), resonant inductive coupling (RIC) and magnetoelectric (ME), are investigated. We find that in the weak–coupling regime, the power optimization and efficiency maximization problems are equivalent and yield the same optimal load and frequency. These properties apply to both topologies under consideration. Despite the apparent difference in the energy conversion mechanisms, the two structures result in similar explicit forms of maximum power delivered to the load, and so does the optimum transfer efficiency. We discuss the essential role of a figure of merit for each configuration and show how they affect the overall performance. For a weakly–coupled inductive WPTS, both the maximum transferred power and efficiency are positively proportional to drive frequency squared. In the case of a ME–based architecture, the dependence of power and efficiency on frequency is the consequence of the transducer geometry optimization problem, subject to a volume constraint. Under a constant mechanical quality factor condition, both quantities are linearly proportional to the operating frequency. While the focus of this paper is RIC and ME mechanisms, some of the findings are also valid for relevant inductive energy harvesting or magneto–mechano–electric WPTSs.