Theoretical Model for Magnetic Supercapacitors-From the Electrode Material to Electrolyte Ion Dependence

Recent results have shown that electrochemical energy storage devices can change their characteristics near the magnetic field environment. Mostly, this change is attributed to the magnetically responsive electrode materials. It is still not expected that significant change can also be induced under a magnetic field by replacing nonmagnetic electrolytes. In this paper, it is clearly shown that this 'change' does occur and its magnitude can be as high as 50%. To date, a Nernstian relation across the electrode is used to explain the supercapacitive behavior of a cell, ignoring the contributions from the magnetic field, even if it is present in the surroundings of the device. Therefore, it is necessary to modify these well-established theoretical models to explain the magnetic field-dependent behavior in energy storage devices. It is shown that the Lorentz force plays a consequential role in inducing colossal changes in the specific capacitance of a supercapacitor. Seven different nonmagnetic electrolytes are combined with Fe2O3 electrodes to prove the proposed concept. The modified theory leads to consistent results, which are corroborated with the experimental data.