Preparation,Structure And Properties Of Energy Storage BST-based Ceramics

Compared with the battery,the dielectric storage capacitor has larger power density,fast charge/discharge rate and high stability.The dielectric energy storage material has become a research hotspot.Due to the adjustable Curie temperature,high dielectric constant and low dielectric loss,Ba1-xSrxTiO3(BST)has attracted much attention in energy storage.However,the high sintering temperature and the low breakdown strength limits its application.Therefore,BST ceramics were investigated in this paper from the following:1)Different sintering methods;2)Effects of MAS addition on the structure and properties of BST ceramics;3)Combining with cyanate ester resin to form the composites,investigation on the structure and energy storage.The Ba1-xSrxTiO3(x=0.1-0.5)ceramics was prepared by traditional solid sintering method and microwave sintering method.The effect of preparation on its properties was studied.The results show that the microwave sintering method reduces the sintering temperature and the holding time compared with the traditional sintering method.The dielectric constant and dielectric loss of ceramic prepared by microwave sintering method are higher than traditional sintering method.The Curie position of Ba1-xSrxTiO3 prepared by the two methods is basically the same.With the increase of x,the BDS of Ba1-xSrxTiO3 ceramics gradually increases.The Ba0.6Sr0.4TiO3 ceramic prepared by microwave sintering method obtained the optimum dielectric properties and energy storage properties:? = 3531,tan? = 0.062,BDS = 11.46 kV/mm and energy storage density is 2.22 J/cm3.The BST ceramics with MAS glass were prepared by traditional sintering method and microwave sintering method.For the BST ceramics,the addition of MAS glass reduces the sintering temperature and improves the temperature stability of dielectric properties.The breakdown electric field strength increases as the amount of MAS glass increases.When the amount of MAS glass is 1wt%,the BST ceramics sintered by traditional method exhibits the best energy storage performance:? = 3748,tan8 = 0.0076,BDS = 16.5 kV/mm,energy storage efficiency is 38%,energy storage density is 1.91 J/cm3.The Microwave sintering method effectively reduces PE loop,which has low remnant polarization.when x = 1wt%,energy storage density is 4.81 J/cm3,the energy storage efficiency is up to 92%.The CE/BST composites materials were prepared.The results show that the cyanate ester resin is filled with pores in the BST ceramic body.Compared to BST ceramics,CE/BST composites has the dielectric constant of 102 and dielectric loss below 0.02.And the electric field strength has significantly improved,the highest BDS reaches 37.49 kV/mm which was 3 times than that of pure BST ceramics.At the same time,CE/BST composite hysteresis loop showed linear,energy storage efficiency was greatly improved.The best performance CE/BST composites is following:? = 254,tan? = 0.015,BDS = 36.8 kV/mm,energy storage efficiency is 80%and energy storage density is 1.39 J/cm3.