Transition Metal Silicate Ion Conductor for Solid-State Batteries
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current metal secondary batteries face limitations in energy density and safety due to the use of toxic liquid electrolytes, and existing solid-state electrolytes struggle to balance performance and safety, particularly in terms of room-temperature ionic conductivity and stability, which restricts their practical application in all-solid-state batteries.
Innovation Solution
A transition metal silicate ion conductor is developed using a solid phase method, involving the preparation of a precursor with specific molar ratios of transition metal salts, sodium salts, and ethyl orthosilicate, followed by sintering and ion exchange processes to achieve high ionic conductivity, resulting in amorphous or crystalline transition metal silicate materials with enhanced room-temperature ionic conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If polymer solid-state electrolyte is used, then dendrite growth is inhibited and safety is improved, but room-temperature ionic conductivity is restricted due to slow structure relaxation and friction action
Solution Approach 1:
The patent employs composite materials by combining inorganic solid-state electrolyte materials (such as oxides, sulfides, or nitrides) with specific crystal structures that facilitate ion transport. This composite approach overcomes the limitations of pure polymer electrolytes by introducing materials with inherently higher ionic conductivity at room temperature while maintaining the safety advantages of solid-state systems.
Solution Approach 2:
The patent utilizes parameter changes by controlling the crystal structure, defect concentration, and compositional parameters of the inorganic electrolyte materials. By adjusting these parameters, the ionic conductivity is enhanced while maintaining structural stability and safety, directly addressing the contradiction between conductivity and safety.
2Quantity of substance
If inorganic crystal material with diffusion channel is used, then room-temperature ionic conductivity is improved, but grain boundaries hinder ion diffusion between grains
Solution Approach 1:
The patent applies local quality by optimizing the properties of grain boundaries specifically. Through compositional control and interface engineering, the grain boundaries are modified to reduce their hindering effect on ion diffusion while maintaining the bulk material's high conductivity characteristics. This localized optimization ensures continuous ion transport throughout the material.
Solution Approach 2:
The patent employs preliminary action by pre-treating or pre-structuring the material during synthesis to minimize grain boundary formation or to create favorable grain boundary characteristics before the material is put into service. This proactive approach reduces the negative impact of grain boundaries on ion diffusion continuity.
3Stability of the object's composition
If fixed lattice of electrolyte is used, then structural stability is provided, but lattice mismatch with crystalline electrode material leads to high interface impedance
Solution Approach 1:
The patent utilizes parameter changes by adjusting the lattice parameters, compositional ratios, and structural characteristics of the electrolyte material. These parameter adjustments enable better lattice matching with electrode materials, reducing interface impedance while preserving the structural stability provided by the fixed lattice.
4Quantity of substance
If thermal defects are increased to improve ion diffusion, then ionic conductivity is enhanced, but activation energy is consumed and defects are difficult to regulate
Solution Approach 1:
The patent employs parameter changes by systematically controlling the concentration and distribution of thermal defects through compositional design and synthesis conditions. This approach enables regulation of defect levels to optimize ionic conductivity while managing the activation energy requirements and avoiding excessive complexity in defect control.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method produces ion conductors with ionic conductivity reaching up to 10−2 S/cm, offering improved safety and performance as solid-state electrolytes for metal ion batteries, with amorphization increasing conductivity and stability, and the materials are cost-effective and suitable for large-scale development.
Implementation Method 1
the diffusion of ions in the channel is driven by the migration of thermal defects in loaded ion sublattice
Implementation Method 2
The solid-state battery uses a solid-state electrolyte that can conduct ions to replace the organic electrolyte
Data Source
AI summary
The present disclosure discloses an ion conductor with high room-temperature ionic conductivity and a preparation method thereof. This method employs solid-phase sintering and ion exchange technologies, and can prepare crystalline and amorphous transition metal silicate by adjusting the addition ratio of sodium source. The chemical formula of the prepared transition metal silicate is A2-2xMSiO4-x, wherein A is Na, Li, Mg, Ca, or Zn; M is a transition metal Fe, Cr, Mn, Co, V, or Ni, when 0<x≤0.5, the prepared transition metal silicate is crystalline, and the degree of crystallization decreases as x increases; and when 0.5<x<1, the transition metal silicate is amorphous.