where a and b are adjustable parameters. For ideal semi-infinite diffusion-controlled charge storage processes, b = 0.5, whereas ideal surface-limited processes exhibit b = 1 ("b-value analysis"). However, assigning kinetics according to this b-value suffers from redox peak shifts/broadening and ohmic drops, especially at higher currents. It is also prone to misinterpretation, often leading to mistakenly labeling "fast" battery materials as (pseudo)capacitive, which is typically encountered when finite-length diffusion leads to b-values between 0.5 and 1. More reliable analysis of electrode kinetics is enabled by electrochemical impedance spectroscopy (EIS), which probes electrochemical processes including ion intercalation kinetics over wide time scales. The resulting Nyquist plots (imaginary vs. real impedance) can be interpreted using electrical equivalent circuits. However, fitting the experimental data is non-trivial, and the use of physical models requires deep prior knowledge of the system. Three-dimensional Bode plot representations of impedance spectra (phase angle / real capacitance vs. frequency vs. electrode potential) have recently been presented for direct visualization of charge storage kinetics, providing the possibility to distinguish doublelayer, pseudocapacitive, and battery-like processes. However, this method utilizes an electrical equivalent circuit of a resistor and a capacitor in series, which is an oversimplification if the entire complexity of a multi-step intercalation processes is investigated.