In this work, homogeneous ceramics-polymer nanocomposites consisting of surface treated BaTiO3 (BT) particles as fillers and poly(vinylidene fluoride) polymer as matrix have been prepared using a solution casting process. The nanocomposites exhibit enhanced dielectric permittivity and reduced loss tangent. The frequency and temperature dependencies of the dielectric permittivity and loss tangent of the nanocomposites suggest that the introduced BT phase and interface areas contribute to the improvement of the dielectric responses. Meanwhile, the X-ray diffraction patterns and Differential Scanning Calorimetry (DSC) curves indicate that the incorporation of ceramic particles contributes to the decrease of the crystallite size, the increase of the crystallinity, and the shift of the crystallization temperature of the polymer matrix. Furthermore, the dielectric displacement and energy density of the nanocomposites are significantly enhanced and an energy density of 3.54 J/cm3 was obtained under an electric field of 200 MV/m with the BT concentration of 20 vol. %. The results indicate that the introduced ceramic fillers and interface areas have positive influences on the structure of the polymer matrix and contribute to the enhancement of the dielectric responses and energy storage properties of the nanocomposites.

Enhanced dielectric properties of BaTiO3/poly(vinylidene fluoride) nanocomposites for energy storage applications

A multilayer ceramic electronic component includes: a ceramic body including dielectric layers; an oxide film formed on one surface of the ceramic body; first and second external electrodes formed on both sides of the oxide film on one surface of the ceramic body; a first internal electrode formed on the dielectric layer and including a first electrode lead-out portion exposed to the first external electrode and a first insulating lead-out portion exposed to the oxide film and having a composite-metal-oxide region formed in an exposed edge portion thereof; a second internal electrode facing the first internal electrode, having the dielectric layer interposed therebetween, and including a second electrode lead-out portion exposed to the second external electrode and a second insulating lead-out portion exposed to the oxide film, having a composite-metal-oxide region formed in an exposed edge portion thereof, and overlapped with the first insulating lead-out portion to form additional capacitance.

Multilayer ceramic electronic component

An electrical-energy-storage unit (EESU) has as a basis material a high-permittivity composition-modified barium titanate ceramic powder. This powder is double coated with the first coating being aluminum oxide and the second coating calcium magnesium aluminosilicate glass. The components of the EESU are manufactured with the use of classical ceramic fabrication techniques which include screen printing alternating multilayers of nickel electrodes and high-permittivitiy composition-modified barium titanate powder, sintering to a closed-pore porous body, followed by hot-isostatic pressing to a void-free body. The components are configured into a multilayer array with the use of a solder-bump technique as the enabling technology so as to provide a parallel configuration of components that has the capability to store electrical energy in the range of 52 kW·h. The total weight of an EESU with this range of electrical energy storage is about 336 pounds.

Electrical-energy-storage unit (EESU) utilizing ceramic and integrated-circuit technologies for replacement of electrochemical batteries

There is provided a multilayer ceramic electronic component includes a ceramic body including a dielectric layer; and an internal electrode formed in the ceramic body, wherein on a cross-section of the ceramic body in a width-thickness direction, a thickness Te of the internal electrode satisfies 0.1 μm≦Te≦1.0 μm, and when the internal electrode is divided into three regions including a central region and both edge regions in a width direction of the ceramic body and a ratio of an actual total length of the internal electrode corresponding to the sum of lengths of electrode portions to an ideal total length of the internal electrode is defined as connectivity S of the internal electrode, connectivity of the internal electrode in the edge regions satisfies 75%≦S≦98%, and a ratio of connectivity of the internal electrode in the edge regions to connectivity of the internal electrode in the central region is 0.9 to 0.98.

Multilayer ceramic electronic component and method of manufacturing the same

A dielectric ceramic composition comprising a predetermined main component and a fifth subcomponent including an oxide of A (note that A is at least one king selected from a cation element group having an effective ionic radius of 0065 nm to 0085 nm at the time of 6 coordination); and the dielectric ceramic composition comprises a plurality of crystal grains including Ca elements and, when assuming that an average value of a concentration of entire Ca exiting in said respective crystal grains is grain Ca concentration, at least unevenness exists in said grain Ca concentration between said crystal grains and it is 5% or higher in a CV value

Dielectric ceramic composition and electronic device

Fine-grained dielectric ceramics, i.e., of 0.2 µm grain diameter, were obtained using Ca-doped BaTiO3 powders consisting of particles 0.2 µm in diameter. The (Ba1-xCax)mTiO3 ceramics (x: 0–0.10, m: 1.003–1.009) showed a high dielectric constant and stable temperature dependence, which were provided by interfacial stress due to the grain boundary, even though the ceramics has no core-shell structure. The failure time under an accelerated life condition was remarkably improved with Ca doping, which may be caused by the decrease in BaTiO3 unit volume with Ca2+ at the Ba2+ lattice site, and Ca2+ acceptor ions at the Ti4+ site.

https://iopscience.iop.org/article/10.1143/JJAP.41.6922/pdf

Dielectric Properties of Fine-Grained BaTiO3 Ceramics Doped with CaO

In a dielectric ceramic having crystal grains and containing a perovskite in which the A site contains Ba and the B site contains Ti. as a main component, the crystal orientations are aligned in substantially the same direction within the crystal grains. Some of Ba may be replaced with Ca and/or Sr, and some of Ti may be replaced with Zr and/pr Hf. This achieves a dielectric ceramic which has a high dielectric constant and has favorable AC electric field characteristics in which the change in dielectric constant is small even with changes in applied electric field.

Dielectric ceramic and multilayer ceramic capacitor

A dielectric ceramic which exhibits small variation in dielectric constant, allows use of a base metal, can be fired in a reducing atmosphere and which is suitable for constituting a dielectric ceramic layer for, e.g., a laminated ceramic capacitor is obtained by firing barium titanate powder in which the c-axis/a-axis ratio in the perovskite structure is about 1.000 or more and less than about 1.003 and the amount of OH groups in the crystal lattice is about 2.0 wt. % or less. The barium titanate powder starting material preferably has a maximum particle size of about 0.3 μm or less and an average particle size of about 0.05-0.15 μm. Each particle of the barium titanate powder preferably comprises a low-crystallinity portion and a high-crystallinity portion, the diameter of the low-crystallinity portion being about 0.5 times or more the particle size of the powder. When sintered, the powder satisfies the ratio of (average grain size of the fired dielectric ceramic)/(average particle size of barium titanate powder starting material), R, of about 0.90-1.2, to thereby suppress considerable grain growth. A laminated ceramic electronic element including a laminate of a plurality of layers of the above-mentioned dielectric ceramic, as well as a method for producing the same, is described.

Dielectric ceramic, method for producing the same, laminated ceramic electronic element, and method for producing the same

Provided is a highly reliable laminated ceramic capacitor in which decrease of dielectric constant under a high electric field is small and which satisfies the B-grade and X7R grade characteristics, using Ni for the inner electrodes, wherein the dielectric material contains about 0.2 to 5.0 parts by weight of Li 2 O—(Si, Ti) 2 —MO oxides (MO is at least one of the compounds of Al 2 O 3 and ZrO 2 ) or SiO 2 —TiO 2 —XO oxides (XO is at least one of the compounds of BaO, CaO, SrO, MgO, ZnO and MnO) relative to 100 parts by weight of a principal component represented by (Ba 1−x Ca x O) m TiO 2 +αRe 2 O 3 +βMgO+γMnO (Re 2 O 3 represents at least one of Y 2 O 3 , Gd 2 O 3 , Tb 2 O 3 , Dy 2 O 3 , Ho 2 O 3 , Er 2 O 3 and Yb 2 O 3 ).

Takashi Hiramatsu

Papers

Dielectric Properties of Fine-Grained BaTiO3 Ceramics Doped with CaO

Dielectric ceramic and multilayer ceramic capacitor

Dielectric ceramic, method for producing the same, laminated ceramic electronic element, and method for producing the same

Dielectric ceramic composition and laminated ceramic capacitor using the same

Investigation of grain boundaries influence on dielectric properties in fine-grained BaTiO3 ceramics without the core–shell structure