Sodium Ion Conductor Composition for Solid-State Battery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The sodium ion conductivity of conventional sodium ion conductors using NaCB9H10 and NaCB11H12 is limited, necessitating an improvement to enhance their performance.
Innovation Solution
A molecular crystal sodium ion conductor is formed by mixing NaCB9H10, NaCB11H12, and a sodium halide, with a mol fraction of the sodium halide ranging from 0 to 70, preferably 0.1 to 60, to suppress the shortage of Na carriers and improve conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If NaCB9H10 and NaCB11H12 are mixed in a 50:50 molar ratio to form a sodium ion conductor, then a stable superionic-conducting structure is achieved, but the sodium ion conductivity is limited and requires further improvement
Solution Approach 1:
The patent changes the compositional parameters by introducing sodium halides (NaF, NaCl, NaBr, or NaI) into the NaCB9H10-NaCB11H12 system. By varying the mol fraction of sodium halide from 0 to 70 and adjusting the ratio of NaCB9H10 to NaCB11H12, the patent achieves enhanced sodium ion conductivity while maintaining structural stability through parameter optimization
Solution Approach 2:
The patent creates a composite material system by combining NaCB9H10, NaCB11H12, and sodium halides into a molecular crystal. This composite approach leverages the complementary properties of each component: the stable framework of carboborate salts and the ionic conductivity enhancement from sodium halides, achieving both structural reliability and improved ion transport
2Quantity of substance
If the sodium halide mol fraction is increased to improve sodium ion conductivity, then more Na carriers are available, but the molecular crystal structure may become unstable beyond a certain composition range
Solution Approach 1:
The patent systematically varies the mol fraction of sodium halide as a key parameter, establishing the optimal range of 0 < x ≤ 70. This parameter optimization balances the competing requirements of having sufficient Na carriers for high conductivity while maintaining the molecular crystal structure's stability
Solution Approach 2:
The patent optimizes the local composition within the molecular crystal by specifying the ratio of NaCB9H10 to NaCB11H12 (50:50 to 90:10). This local compositional control ensures that the carboborate framework maintains its stabilizing role while accommodating the sodium halide content needed for high ion conductivity
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 modified sodium ion conductor exhibits enhanced sodium ion conductivity, making it suitable for use in solid-state sodium-ion batteries with improved performance.
Implementation Method 1
a sodium ion conductor whose sodium ion conductivity is improved more than the conventional can be produced via formation of a molecular crystal by mixing a sodium halide with NaCB9H10 and NaCB11H12. This is believed to be because containing a sodium halide within a given range suppresses a shortage of Na carriers in the sodium ion conductor.
Data Source
AI summary
Provided is a sodium ion conductor whose sodium ion conductivity is improved more than the conventional. The sodium ion conductor is a molecular crystal constituted of NaCB9H10, NaCB11H12, and a sodium halide, the sodium halide having a mol fraction of more than 0 and at most 70 on the basis of the total mol ratio of NaCB9H10, NaCB11H12, and the sodium halide.