Pyrolyzed Metal Anode Coating for Sodium-Ion Batteries
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Sodium-ion batteries face challenges with metal anodes due to volume changes during charge and discharge, leading to performance degradation, and existing non-sodium metal anodes have limitations in capacity and stability.
Innovation Solution
A method for fabricating metal battery electrodes with a pyrolyzed coating using metallorganic compounds, where metal particles are coated with carbides, nitrides, or sulfides, formed through pyrolysis, to mitigate volume changes and enhance stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If metal particles are used as battery anodes, then capacity is improved, but volume changes during charge and discharge cause pulverization and performance degradation
Solution Approach 1:
The patent creates a composite structure where metal particles are embedded within a carbonaceous matrix. The carbonaceous material serves as a stable host that accommodates the metal particles and mitigates their volume expansion during lithiation, while still allowing for high capacity through the synergistic combination of both materials.
Solution Approach 2:
The carbonaceous coating acts as a flexible shell surrounding the metal particles. This shell can expand and contract with the metal core during charge-discharge cycles, preventing mechanical failure while maintaining structural integrity and preventing direct contact between the metal particles and the electrolyte.
2Reliability
If carbonaceous materials are used as anodes, then stability is improved, but capacity is limited compared to metal anodes
Solution Approach 1:
The patent merges the advantages of both metal particles (high capacity) and carbonaceous materials (stability) into a single composite electrode structure. The metal particles provide the high capacity through alloying reactions, while the carbonaceous matrix provides structural stability and conductivity, achieving both high capacity and stability simultaneously.
3Reliability
If metal particles are coated with carbonaceous material, then pulverization is reduced, but particle size increases
Solution Approach 1:
The carbonaceous coating is applied locally around each metal particle rather than as a thick uniform layer. This thin conformal coating provides just enough protection against pulverization and electrolyte contact while minimizing the increase in overall particle size, maintaining good electrochemical performance.
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 pyrolyzed coating process results in small particle sizes and stable metal anodes that reduce pulverization during battery cycles, improving capacity retention and cyclability.
Implementation Method 1
A method for fabricating metal battery electrodes with a pyrolyzed coating using metallorganic compounds
Data Source
AI summary
A method is provided for forming a metal battery electrode with a pyrolyzed coating. The method provides a metallorganic compound of metal (Me) and materials such as carbon (C), sulfur (S), nitrogen (N), oxygen (O), and combinations of the above-listed materials, expressed as MeXCYNZSXXOYY, where Me is a metal such as tin (Sn), antimony (Sb), or lead (Pb), or a metal alloy. The method heats the metallorganic compound, and as a result of the heating, decomposes materials in the metallorganic compound. In one aspect, decomposing the materials in the metallorganic compound includes forming a chemical reaction between the Me particles and the materials. An electrode is formed of Me particles coated by the materials. In another aspect, the Me particles coated with a material such as a carbide, a nitride, a sulfide, or combinations of the above-listed materials.