Multilayer PZT 95/5 Antiferroelectric Film Energy Storage Devices with Giant Power Density.

A new type of energy storage devices utilizing multilayer Pb(Zr0.95 Ti0.05 )0.98 Nb0.02 O3 films is studied experimentally and numerically. To release the stored energy, the multilayer ferroelectric structures are subjected to adiabatic compression perpendicular to the polarization direction. Obtained results indicate that electrical interference between layers (10-120 layers) during stress wave transit through the structures has an effect on the generated current waveforms, but no impact on the released electric charge. The multilayer films undergo a pressure-induced phase transition to antiferroelectric phase at 1.7 GPa adiabatic compression and become completely depolarized, releasing surface screening charge with density equal to their remnant polarization. An energy density of 3 J cm-3 is successfully achieved with giant power density on the order of 2 MW cm-3 , which is four orders of magnitude higher than that of any other type of energy storage device. The outputs of multilayer structures can be precisely controlled by the parameters of the ferroelectric layer and the number of layers. Multilayer film modules with a volume of 0.7 cm3 are capable of producing 2.4 kA current, not achievable in electrochemical capacitors or batteries, which will greatly enhance the miniaturization and integration requirements for emerging high-power applications.

Ultrahigh energy density harvested from domain-engineered relaxor ferroelectric single crystals under high strain rate loading.

Relaxor ferroelectric single crystals have triggered revolution in electromechanical systems due to their superior piezoelectric properties. Here the results are reported on experimental studies of energy harvested from (1-y-x)Pb(In1/2Nb1/2)O3-(y)Pb(Mg1/3Nb2/3)O3-(x)PbTiO3 (PIN-PMN-PT) crystals under high strain rate loading. Precise control of ferroelectric properties through composition, size and crystallographic orientation of domains made it possible to identify single crystals that release up to three times more electric charge density than that produced by PbZr0.52Ti0.48O3 (PZT 52/48) and PbZr0.95Ti0.05O3 (PZT 95/5) ferroelectric ceramics under identical loading conditions. The obtained results indicate that PIN-PMN-PT crystals became completely depolarized under 3.9 GPa compression. It was found that the energy density generated in the crystals during depolarization in the high voltage mode is four times higher than that for PZT 52/48 and 95/5. The obtained results promise new single crystal applications in ultrahigh-power transducers that are capable of producing hundreds kilovolt pulses and gigawatt-peak power microwave radiation.