The electrocaloric effect (ECE) is a phenomenon observed in dielectric materials, where a reversible temperature/entropy change occurs due to the alignment and reordering of dipoles under an applied electric field.
When an electric field is applied, the dipoles within the dielectric material align, leading to a decrease in dipolar entropy and the release of heat, resulting in a temperature rise.
[1] Conversely, when the electric field is removed, the dipoles return to a more disordered state, causing the material to absorb heat from its surroundings, resulting in a temperature decrease.
The study highlighted thin films' potential for solid-state cooling and suggested further material improvements could enhance practical applications.
[9][10] The EC effect involves a temperature change in a dielectric material when an electric field is applied or removed, making it suitable for compact cooling solutions.
Under an electric field of 16.6 MV/m, these elements achieved a temperature span of 0.9 K. Same year in 2017 researchers designed a compact and flexible electrocaloric cooling device by integrating an EC polymer film with electrostatic actuation.
[15] In 2020, researchers demonstrated an active EC regenerator, with the innovation involved a parallel-plate design using lead scandium tantalate (PST) multilayer capacitors, optimized through finite element modeling to enhance insulation and heat transfer.
By leveraging a modular, self-regenerating architecture and enhancing both material properties and device engineering, the system achieved a temperature span of 5.2 °C and a maximum heat flux of 135 mW/cm².
A significant advancement in 2020 is the development of a cascade electrocaloric device, which increases the temperature span by integrating multiple EC polymer elements that operate in synergy.
In 2023, researchers developed an EC device using PST multilayer capacitors that achieved a maximum temperature span of 20.9 K under no-load conditions and a cooling power of 4.2 W under a moderate electric field.
[19] With a coefficient of performance (COP) reaching up to 64% of Carnot's efficiency when energy recovery was considered, this design marks a significant step toward making EC technology a viable alternative to traditional vapor compression cooling systems.
These advances highlight the potential of EC technology to provide efficient, localized thermal management solutions without the need for external actuators.