Study On Energy Storage Performance Of PLZST Based Ceramics And Charge/Discharge Characteristics Of Multilayer Ceramic Capacitor

As one of the basic disciplines of modern high technology,pulse power technology has been widely used in industrial manufacturing,geological exploration,metal pulse forming processing,laser medical equipment,and impulse voltage.Moreover,with the urgency of the energy crisis,the high energy storage devices in the pulse power system are driven by greater development.Capacitors have the advantages of low cost,high power density and fast discharge,making them the most widely used storage.Firstly,from the material point of view,the development of dielectrics with high energy storage density,and then verify the charge and discharge performance of multilayer capacitors,which has become the main mode of research on the direction of capacitive energy storage in the industry.(Pb_0.97La_0.02)?Zr,Sn,Ti?O₃?PLZST?-based antiferroelectric materials,which have attracted much attention due to their high energy density,remanent polarization of almost zero,and characteristic phase transition behavior.This paper first studies the energy storage characteristics of antiferroelectric?AFE?materials from two aspects,and then verifies the charge and discharge characteristics of multilayer capacitors.It provides some ideas for the research of capacitor energy storage.The specific performance is as follows:?1?Due to the strong component dependence of PLZST antiferroelectric ceramics,the high Ti⁴⁺content and high Zr⁴⁺amount will weaken the antiferroelectric phase,which is unfavorable for the improvement of storage energy density.The PLZST component was positioned in the tetragonal phase region,the low Ti⁴⁺content was kept unchanged,the Zr⁴⁺content was varied by 50%,and the Sn⁴⁺content was increased.The transformation process becomes the AFE phase to the multi-cubic paraelectric phase and then to the unit cubic PE phase,which delays the phase transition process,and the front transition field increases from 17.94kV/mm to 21.75kV/mm.The component dependence is characterized by two forms of bulk and hierarchical ceramics.Due to the limitation of the process,the breakdown strength of the block is only 16kV/mm,which also results in the release energy density of the block is less than 0.9J/cm³,however,the uniform grain distribution of the layered ceramics increased the breakdown strength by 44%,with the increase of Sn⁴⁺content,the ceramics released energy density increased first and then decreased,and when the Sn⁴⁺content was 0.44,the energy storage density achieved a maximum,2.897J/cm³,and the efficiency is 78.17%.?2?The high-valent cation Sm³⁺acts as a donor doping to replace Pb²⁺at the A-site,which can improve the stability of antiferroelectricity.Highly polarized ceramic(Pb_0.97La_0.02)(Zr_0.675Sn_0.285Ti_0.04)O₃ was selected as the matrix,and the increase of Sm³⁺caused the decrease of the maximum polarization.When the doping amount of Sm³⁺was1%,the recoverable energy storage density is 3.835J/cm³,and the energy storage efficiency is 75.96%.?3?According to the preferred formulation,the compatibility of the MLCC process was verified by a charge and discharge test of an 8-layer capacitor,and a 30-layer ceramic capacitor having a dielectric layer thickness of 30?m was prepared,and the capacitance was 650nF,and the loss was less than 0.009.The discharge energy density of the capacitor which was measured by the self-constructed charge and discharge circuit with a withstand voltage of 900V reached 1.268 J/cm³,and the efficiency was 78.09%.In the short-circuit discharge test of the pulse power system,the discharge current reached 3660A in the688ns period under the 800V charging voltage,indicating that the ceramic material and the 30-layer ceramic capacitor prepared by the process can be applied to the pulse power systems which requiring high energy density.