This paper proposed a novel switching scroll hyperchaotic system based on a memristor device and explored its application to secure communication. The new system could be switched between the double-scroll chaotic system and multiscroll one by switch S1 and switch S2. We gave the construction process of the novel system, its numerical simulations, and dynamical properties, firstly. Moreover, the memristive circuit implementation of the new switching system was presented and the results were also in agreement with those of numerical simulation. Finally, the new switching memristive system was applied to secure communication by means of the drive-response synchronization with chaotic masking. When the voice signal is a rising waveform, it is encrypted by the double-scroll memristive system. When the voice signal is a falling waveform, the multiscroll memristive system works. The voice signal is completely submerged in the chaotic signal and could not be distinguished at all. Security analyses show that it is a successful application to secure communication.

As a non-destructive test method, electrochemical impedance spectroscopy (EIS) has been widely used in the analysis and diagnosis of Li-ion batteries in recent years. But the study of the high-frequency characteristics of Li-ion batteries is still not enough and the performance of Li-ion batteries at high frequency is not the same with that of the pure capacitance or pure inductance. Based on EIS, a fractional equivalent circuit model considering high-frequency inductance characteristics is established in frequencies from 10mHz to 10kHz in this paper. Then the model is verified and the parameters of the circuit are explored by using differential evolution (DE) algorithm and fractional-order numerical operations. Compared with the traditional equivalent circuit model, a fractional-order model based on EIS can not only describe the characteristics of the battery more comprehensively but also reduce the number of parameters because each component can simulate a certain physicochemical process of Li-ion batteries. The dominant process of the battery reaction is diverse in different frequency bands and therefore the structure of the developed model can be simplified accordingly. For the high-frequency inductive analysis of the battery, results show that the battery's 'inductancelike' phenomenon has a certain relationship with the frequency. This discovery might be implemented in a power electronic circuit to improve understanding of how batteries react to working condition of high-frequency.