Core-Shell Dielectric Composition for Stable High-Field Permittivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current dielectric compositions lack optimal temperature characteristics and high-temperature load life, particularly under high electric fields, necessitating a composition with improved relative permittivity and reliability.
Innovation Solution
A dielectric composition featuring a core-shell structure with specific rare earth elements and silicon content, where the ratio of RA to RB in the shell exceeds that in the core, and segregation particles with a higher RB content, enhancing temperature stability and permittivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a dielectric composition with conventional rare earth element addition is used, then the basic dielectric properties are maintained, but the temperature characteristics and high-temperature load life are insufficient
Solution Approach 1:
The invention divides the dielectric ceramic into two distinct regions: a core region with specific rare earth element content for high permittivity, and a shell region with different rare earth element composition for temperature stability. This segmentation allows each region to optimize its function independently, resolving the contradiction between maintaining high dielectric properties and achieving temperature stability.
Solution Approach 2:
The invention applies different rare earth element compositions to different parts of the ceramic structure. The core contains one type of rare earth element composition optimized for permittivity, while the shell contains a different composition optimized for temperature characteristics. This local differentiation enables simultaneous optimization of both reliability and temperature performance.
2Reliability
If the relative permittivity is increased to improve capacitance, then the dielectric performance is enhanced, but the temperature stability deteriorates
Solution Approach 1:
The dielectric ceramic is segmented into core and shell regions with different rare earth element compositions. The core region is optimized for high relative permittivity while the shell region is optimized for temperature stability, allowing both properties to be maximized simultaneously without compromising either characteristic.
Solution Approach 2:
The invention creates a composite structure combining two different rare earth element-doped perovskite phases with distinct functionalities. The core phase provides high permittivity while the shell phase provides temperature compensation, resulting in a composite material that achieves both high relative permittivity and excellent temperature stability.
3Power
If high electric field strength is applied to increase power density, then the energy storage capacity is improved, but the high-temperature reliability decreases
Solution Approach 1:
The ceramic is divided into core and shell regions where the shell acts as a protective layer that maintains structural integrity under high electric fields and high temperatures. This segmentation allows the core to operate at high power density while the shell ensures long-term reliability under combined high-temperature and high-electric-field conditions.
Data Source
AI summary
A dielectric composition includes main-phase particles each including a main component having a perovskite crystal structure represented by a general formula of ABO3. At least a part of the main-phase particles has a core-shell structure. The dielectric composition includes RA, RB, M, and Si. Each of A, B, RA, RB, and M is one or more elements selected from a specific element group. SRA/SRB>CRA/CRB is satisfied, where CRA is an RA content (mol %) to the main component in terms of RA2O3, and CRB is an RB content (mol %) to the main component in terms of RB2O3, in the dielectric composition, and SRA is an average RA content (mol %), and SRB is an average RB content (mol %), in a shell part of the core-shell structure.