Enhancing Efficiency in Electrocaloric Cooling: A Study on Voltage-Dependent Material Losses

Electrocaloric P(VDF-TrFE-CFE) (PVDF) films are routinely characterized using sinusoidal excitation at a few hundred hertz, yet this approach overlooks the profound influence of excitation profiles on material losses. Here, we compare losses under sinusoidal/trapezoidal waveforms (high-voltage amplifier) and practical power supplies (half-bridge/flyback). Strikingly, losses increase by 200-300% when using such power supplies, revealing that real-world driving conditions can dominate performance. These findings challenge the relevance of standard loss metrics and emphasize the need to co-optimize power supply and materials in electrocaloric devices.