The electrocaloric effect (ECE), i.e., the conversion of the electric into the thermal energy has recently become of great importance for development of a new generation of cooling technologies. Here, we explore utilization of [Pb(Mg1/3Nb2/3)O3]0.9[PbTiO3]0.1 (PMN-10PT) relaxor ceramics as active elements of the heat regenerator in an ECE cooling device. We show that the PMN-10PT relaxor ceramic exhibits a relatively large electrocaloric change of temperature TEC )1 K at room temperature. The experimental testing of the cooling device demonstrates the efficient regeneration and establishment of the temperature span between the hot and the cold sides of the regenerator, exceeding several times the TEC within a single PMN-10PT ceramic plate.
COBISS.SI-ID: 13878299
A substantial enhancement of the electrocaloric (EC) effect is achieved by a properly engineered ceramic microstructure. The EC response of a material is limited by its dielectric breakdown strength, which increases with an increasing density and decreasing grain size. For the material with an ~98 % relative density and 3.6-μm grains, the EC temperature change of 3.45 °C is achieved at an electric field amplitude of 160 kV/cm, which is the highest reported so far for Pbbased perovskites.
COBISS.SI-ID: 28945447
Multilayer elements of relaxor-ferroelectric PMN-10PT exhibit the electrocaloric (EC) temeprature change of 2.26 K at the field of 100 kV/cm, comaprable to the EC effect of bulk ceramics. This makes them a suitable candidate for solid-state cooling devices based on the EC effect.
COBISS.SI-ID: 29796903
The absence of fatigue of the electrocaloric (EC) effect is of utmost importance for applications. Multilayer elements of relaxor PMN ceramic exhibit after 10exp6 unipolar cycles at 110 kV/cm almost unchanged EC effect, the drop of only 0.01 K was determined. This fatigue-less EC response makes PMN multilayers a viable candidate for cooling applications.
COBISS.SI-ID: 30569511
We explored the effect of electric-energy recovery and heat regeneration on the energy efficiency of an electrocaloric (EC)cooling system. The influence of the polarization electric field hysteresis on the energy efficiency of the system is analysed - relaxor compositions (PMN, PMN-10PT) exhibit much lower hysteresis losses than morphotropic phase boundary ones (PMN-35PT). We showed that relaxor compositions together with a highlevel of energy regeneration contribute to a highly efficient EC cooling system.
COBISS.SI-ID: 14221083